Effects of estrus synchronization using Matrix® followed by treatment with the GnRH agonist triptorelin to control ovulation in mature gilts.

PubMed

Knox, R V; Webel, S K; Swanson, M; Johnston, M E; Kraeling, R R

2017-10-01

Estrus and ovulation responses in Matrix-treated gilts may affect ovulation synchrony in response to triptorelin. In experiment 1, estrus and ovulation measures at 12h intervals after last Matrix feeding (LMF) were analyzed. For the 398 gilts that displayed estrus, 87.4% were detected on Days 6-8 after LMF. Duration of estrus was 24-60h for 85.6% of gilts and negatively correlated with interval from LMF to estrus (r=-0.53, P<0.0001). The estrus to ovulation interval was positively correlated with duration of estrus (r=0.61, P<0.0001). In experiment 2, gilts (n=96) received intravaginal treatment with 2mL of gel containing placebo (Control) at 96h, 200μg of triptorelin at 96h (TRP96), 120h (TRP120) or 144h (TRP144) after LMF. Estrus measures did not differ (P>0.10) among treatments. The proportion of gilts ovulating 32-56h after treatment was greater for TRP120 and TRP144 (P<0.01) compared to other treatments. The treatment to ovulation intervals for all triptorelin treatments were shorter (P<0.001) than Control. In experiment 3, gilts (n=86) received placebo (Control), 100μg (TRP100), 200μg (TRP200), or 400μg (TRP400) of triptorelin at 120h after LMF. There was no effect of treatment (P>0.10) on estrus or on interval from LMF to estrus. The proportion of gilts ovulating by 40, 48 and 56h after treatment increased (P<0.05) with triptorelin compared to Control. Our results indicate that gilts receiving 100-400μg of triptorelin at 120h after LMF had the greatest ovulation synchrony 24-48h following treatment. These studies provide important information for developing a procedure for a single insemination in synchronized gilts. Copyright © 2017 Elsevier B.V. All rights reserved.

Control of the estrous cycle to improve fertility for fixed-time artificial insemination in beef cattle: a review.

PubMed

Lamb, G C; Dahlen, C R; Larson, J E; Marquezini, G; Stevenson, J S

2010-04-01

Early estrus-synchronization protocols focused on regressing the corpus luteum (CL) with an injection of PGF(2alpha) followed by detection of estrus or involved the use of exogenous progestins that prevent estrus from occurring. Later, protocols combining the use of PGF(2alpha) and exogenous progestins were developed. Gonadotropin-releasing hormone was utilized to control follicular waves, synchronize ovulation, or to luteinize large dominant follicles. Our research aimed to develop reliable protocols that 1) relied solely on fixed-timed AI (TAI); 2) required a maximum of 3 animal handlings, and 3) were successful in estrous-cycling and noncycling females. In cows, insertion of an intravaginal progesterone insert during the 7-d interval between the initial GnRH and PGF(2alpha) injections enhanced pregnancy rates by 9 to 10%. In a multi-location study, a TAI protocol yielded pregnancy rates similar to a protocol involving detection of estrus plus a fixed-time clean-up AI for females not detected in estrus (54 vs. 58%, respectively, for cows and 53 vs. 57%, respectively, for heifers). Initiation of estrous cycles in noncycling cows is likely the primary manner in which beef producers may improve fertility in response to estrus synchronization and TAI protocols. Treatment of noncycling females with progesterone and GnRH increases the percentage of cycling females and improves fertility to a TAI, but inducing cyclicity with hCG failed to enhance fertility in TAI protocols. Supplementing progesterone after TAI failed to increase pregnancy rates in beef cattle. In contrast, administration of hCG 7 d after TAI induced an accessory CL, increased progesterone, and tended to enhance pregnancy rates. Development of TAI protocols that reduce the hassle factors associated with ovulation synchronization and AI provide cattle producers efficient and effective tools for capturing selective genetic traits of economic consequences. Location variables, however, which may include differences in pasture and diet, breed composition, body condition, postpartum interval, climate, and geographic location, affect the success of TAI protocols.

The 9-day CIDR-PG protocol: Incorporation of PGF2α pretreatment into a long-term progestin-based estrus synchronization protocol for postpartum beef cows.

PubMed

Thomas, Jordan M; Bishop, Brianne E; Abel, Jillian M; Ellersieck, Mark R; Smith, Michael F; Patterson, David J

2016-06-01

A pilot experiment was designed to test the hypothesis that administration of PGF2α before progestin treatment would allow for a reduced duration of progestin treatment in a long-term progestin-based estrus synchronization protocol. A modified presynchronization treatment was compared with a standard long-term controlled internal drug release (CIDR) treatment, and treatments were compared on the basis of ovarian follicular dynamics, estrous response rate, synchrony of estrus expression, and pregnancy rates resulting from timed artificial insemination (TAI) in postpartum beef cows. Estrous was synchronized for 85 cows, with cows assigned to one of two treatments based on age, days postpartum, and body condition score. Cows assigned to the 14-day CIDR-PG protocol received a CIDR insert (1.38 g progesterone) on Day 0, CIDR removal on Day 14, and administration of PGF2α (25 mg im) on Day 30. Cows assigned to the 9-day CIDR-PG protocol received PGF2α concurrent with CIDR insertion on Day 5, PGF2α concurrent with CIDR removal on Day 14, and administration of PGF2α on Day 30. In both treatments, split-time AI was performed based on estrous response. At 72 hours after PGF2α (Day 33), cows having expressed estrus received TAI; cows that failed to express estrus by 72 hours received TAI 24 hours later (96 hours after PGF2α on Day 34), with GnRH (100 μg im) administered to nonestrous cows. Estrus-detection transmitters were used from CIDR removal until AI to determine onset time of estrus expression both after CIDR removal and after PGF2α. Ovarian ultrasonography was performed at CIDR removal on Day 14, PGF2α on Day 30, and AI on Days 33 or 34. At CIDR removal on Day 14, diameter of the largest follicle present on the ovary was similar between treatments. The proportion of cows expressing estrus after CIDR removal tended to be higher (P = 0.09) among cows assigned to the 9-day CIDR-PG treatment (93%; 40 of 43) than among cows assigned to the 14-day CIDR-PG treatment (81%; 34 of 42). After PGF2α, a significantly higher proportion (P = 0.02) of cows expressed estrus after synchronization with the 9-day CIDR-PG treatment (91%; 39 of 43) than the 14-day CIDR-PG treatment (69%; 29 of 42). Consequently, pregnancy rate to TAI tended to be increased (P = 0.09) among the 9-day CIDR-PG treatment (76.7%; 33 of 43) compared with the 14-day CIDR-PG treatment (59.5%; 25 of 42). In summary, a long-term CIDR-based estrous synchronization protocol for postpartum beef cows was enhanced through administration of PGF2α at CIDR insertion and CIDR removal. Copyright © 2016 Elsevier Inc. All rights reserved.

Synchronization of ovulation and fertility in weaned sows treated with intravaginal triptorelin is influenced by timing of administration and follicle size.

PubMed

Knox, R V; Willenburg, K L; Rodriguez-Zas, S L; Greger, D L; Hafs, H D; Swanson, M E

2011-01-15

A 100 μg dose of triptorelin was tested for synchronizing ovulation in sows. In Experiment 1, conducted in April through June, sows (n = 125) were assigned to Control (untreated), TG-96 (Triptorelin Gel (TG) given intravaginally at 96 h post-weaning), or TG-E (given intravaginally at estrus). To optimize AI timing, sows were inseminated at 2 and 26 h after estrus for Control and TG-E and at 8 and 32 h following TG-96. Ovulation by 48 h post-treatment tended to be affected by treatment (P = 0.08) and more (P < 0.05) TG-96 sows ovulated (57.9%) compared to Controls (34.2%), but TG-E (45.1%) did not differ (P > 0.10). Duration of estrus was reduced (P < 0.005) in TG-96 (51 h) and TG-E (58 h) compared to Controls (65 h). There was no treatment effect on farrowing rate (71%) or total born (10.4). Average follicle size <6.5 mm at 96 h after weaning was associated with reduced (P < 0.01) estrus, ovulation and farrowing rate. Experiment 2 was conducted in August through September using 503 weaned sows. The TG-96 treatment reduced duration of estrus (P = 0.03), but treatment did not affect estrus expression, farrowing rate or total pigs born. In conclusion, use of a 100 μg dose of triptorelin intravaginally at 96 h or at estrus advanced ovulation and when used with timed insemination, resulted in similar farrowing rates and litter sizes comparable to sows mated based on estrus. However, ovulation induction and timed AI success may benefit from an approach that ensures sows have adequate follicle development at time of treatment. Copyright © 2011 Elsevier Inc. All rights reserved.

Effects of season and ovarian status on the outcome of long-term progesterone-based estrus synchronization protocols and ovulatory follicle development in Santa Inês ewes under subtropical conditions.

PubMed

Oliveira, M E F; Ayres, H; Oliveira, L G; Barros, F F P C; Oba, E; Bicudo, S D; Bartlewski, P M; Fonseca, J F; Vicente, W R R

2016-02-01

This study set out to investigate the efficiency of long-term estrus synchronization protocols and ovulatory follicle dynamics in ultrasonographically monitored Santa Inês ewes during lengthening (LD; September-October) and shortening photoperiods (SD; April-May), and the transitional period (TP; January). In addition, the influence of ovarian status (e.g., size of antral follicles and/or presence of corpora lutea) at the outset of the estrus synchronization protocols on the ensuing development of ovulatory follicles was examined. Seventy sexually mature Santa Inês ewes were subjected to one of the two estrus synchronization regimens; on Day 0 (random day of the estrous cycle or anovulatory period), the ewes were fitted with an intravaginal progesterone (P4)-releasing (controlled intrauterine drug release [CIDR]) device, which was left in place for 14 days (G-1CIDR, n = 35) or replaced on Day 7 (G-2CIDR, n = 35), and received an intramuscular injection of 10 mg of PGF2α. The ewes allocated to the G-1CIDR group had mean serum P4 concentrations less than 2 ng/mL during the last 4 days of the synchronization protocol. There were no differences (P > 0.05) in mean ovulation rates between the two protocols tested nor among the ewes varying in ovarian status or studied at different times of the year, but ovulations occurred ∼ 12 hours later in the TP compared with the SD period (P < 0.05). Ovulatory follicles emerged earlier (P < 0.05) in the G-1CIDR group than in the G-2CIDR group (Day 8.3 ± 0.5 vs. 9.2 ± 0.4) and during LD (Day 7.1 ± 0.6) compared with the TP (Day 9.1 ± 0.6) and SD (Day 9.9 ± 0.5 of the protocol). In conclusion, the replacement of CIDR devices prevented the occurrence of lower-than-normal luteal phase levels of P4 at the end of the 14-day estrus synchronization protocol. However, although this procedure and seasonal influences altered certain growth characteristics of ovulatory follicles, there were no effects of these factors on the mean ovulation rate. Copyright © 2016 Elsevier Inc. All rights reserved.

Relationship of ruminal temperature with parturition and estrus of beef cows.

PubMed

Cooper-Prado, M J; Long, N M; Wright, E C; Goad, C L; Wettemann, R P

2011-04-01

Spring-calving Angus cows (n = 30) were used to evaluate changes in ruminal temperature (RuT) related to parturition and estrus. Cows were synchronized and artificially inseminated with semen from a single sire. Temperature boluses were placed in the rumen at 7.0 ± 0.2 mo of gestation. Boluses were programmed to transmit RuT every 15 min. Cows (BW = 623 ± 44 kg, BCS = 4.9 ± 0.4) calved during 3 wk, and estrus was synchronized at 77 ± 7 d after calving with PGF(2α). Cows were observed every 12 h to detect estrus. Daily average ambient temperatures ranged from 2 to 22 °C during parturition (February to March) and 17 to 25 °C during estrus (May to June). Ruminal temperature from 7 d before to 3 d after parturition and 2 d before to 2 d after visual detection of estrus was analyzed using the MIXED procedure. Ruminal temperatures <37.72 °C were attributed to water consumption and excluded from analyses. Day did not influence (P = 0.36) RuT from d -2 to -7 before parturition (38.94 ± 0.05 °C). Ruminal temperature decreased (P < 0.001) from d -2 to d -1 before parturition (38.88 ± 0.05 to 38.55 ± 0.05 °C, respectively). Ruminal temperature was not influenced (P = 0.23) by day from 1 d before to 3 d after parturition (38.49 ± 0.05 °C). Ruminal temperature at 0 to 8 h after detection of estrus (38.98 ± 0.09 °C) was greater (P < 0.001) compared with RuT at the same daily hour of the day before (38.37 ± 0.11 °C) or the day after estrus (38.30 ± 0.09 °C). Ambient temperature did not influence (P > 0.30) RuT at parturition or estrus. Ruminal temperature decreased the day before parturition and increased at estrus in spring-calving beef cows and has potential use as a predictor of parturition and estrus.

Control of the estrous cycle in guinea-pig (Cavia porcellus).

PubMed

Grégoire, A; Allard, A; Huamán, E; León, S; Silva, R M; Buff, S; Berard, M; Joly, T

2012-09-01

The aim of this work was to look for a simple method to obtain synchronized ovulation in guinea pigs under farming conditions while respecting animal welfare. The luteolytic activity of three different prostaglandins F2alpha (PGF2α) analogs (D-cloprostenol, D,L-cloprostenol and luprostiol) and a daily treatment with oral progestagen (altrenogest) was tested successively at different stages of the estrous cycle on the same group of females during a period of 8 mo. The estrous cycle length was not modified by the administration of PGF2α analogs, whatever the stage of the estrous cycle when the treatment was initiated. Our results led us to reject the use of PGF2α analog to induce practical synchronization of the estrus in this species. In females (n = 29), given 15 days with altrenogest (0.1 mL po once a day), ovulation occurred 4.43 ± 0.13 days after the end of the treatment. Altrenogest treatment was followed by mating. No negative impacts of the treatment on the pregnancy rates, delivery rates and litter sizes were observed. This standard method of guinea-pig estrus synchronization is less stressful for the animals compared to techniques using progesterone tubing. Copyright © 2012 Elsevier Inc. All rights reserved.

Comparison of estrus synchronization by controlled internal drug release device (CIDR) and adhesive transdermal progestin patch in postpartum beef cows.

PubMed

Kajaysri, Jatuporn; Chumchoung, Chaiwat; Wutthiwitthayaphong, Supphathat; Suthikrai, Wanvipa; Sangkamanee, Praphai

2017-09-15

Estrous synchronization with progesterone based protocols has been essentially used in cattle industry. Although intravaginal devices have been commonly used, this technique may induce vaginitis. This study aimed at examining the efficiency of novel transdermal progestin patch on follicle development and comparing the progestin patch versus CIDR device on estrous synchronization, complication at treated site and pregnancy in beef cattle. In experiment 1, seven beef cows were treated with an adhesive transdermal progestin patch on the ventral surface of the proximal part of the tail for 7 days. The cows were daily examined the follicular development using ultrasonography starting on Day 0 till 3 days after hormone removal. Experiment 2, forty beef cows were divided into two equal groups (20 cows per group). The cows randomly allocated to received either vaginal insertion of CIDR (n = 20) or treated with an adhesive transdermal progestin patch (n = 20). The levels of plasma progesterone during the experiment and the numbers of standing estrous cows were recorded. Timed artificial inseminated (TAI) was performed at 60 h after CIDR or patch termination. Pregnancy rates were determined at 60 days after TAI. Experiment 1 revealed that the novel transdermal progestin patch could efficiently control follicular growth. All the seven treated cows had dominant follicle upon dermal patch removal indicating the effectiveness of the progestin patch. In experiment 2, the percentages of cows exhibited standing estrus were similar between transdermal patch (72.22%) and CIDR (70.00%). The levels of plasma progesterone during CIDR treatment were significantly higher (4.06 ± 1.65 ng/mL on Day 1 and 3.62 ± 1.60 ng/mL on Day 7) compared with transdermal patch (2.60 ± 1.43 ng/mL on Day 1 and 1.81 ± 1.57 ng/mL on Day 7). Three cows treated with CIDR (15%) developed vaginitis while none of cows had physically dermal reaction at adhesive site. Cows synchronized with these two protocols had similar pregnancy rates (50.00%) following fixed time artificial insemination. It is concluded that transdermal progestin patch was equally effective in estrus synchronization as compared with traditional CIDR. However, the transdermal patch demonstrated less complication. This device should therefore be considered as an alternative method for estrus synchronization in postpartum beef cattle. Copyright © 2017 Elsevier Inc. All rights reserved.

Evaluating the interaction between progesterone, TNF alpha and cortisol on early loss of transferred embryos in beef cows

USDA-ARS?s Scientific Manuscript database

Fifty-eight non-lactating cows previously synchronized for estrus were assigned to two treatments to assess the effects of progesterone supplementation and its correlation with TNF-a and cortisol on the survival of the transferred embryos. On day 7 after exhibiting estrus (day 0), cows in both group...

Technical note: a novel approach to the detection of estrus in dairy cows using ultra-wideband technology.

PubMed

Homer, E M; Gao, Y; Meng, X; Dodson, A; Webb, R; Garnsworthy, P C

2013-10-01

Detection of estrus is a key determinant of profitability of dairy herds, but estrus is increasingly difficult to observe in the modern dairy cow with shorter duration and less-intense estrus. Concurrent with the unfavorable correlation between milk yield and fertility, estrus-detection rates have declined to less than 50%. We tested ultra-wideband (UWB) radio technology (Thales Research & Technology Ltd., Reading, UK) for proof of concept that estrus could be detected in dairy cows (two 1-wk-long trials; n=16 cows, 8 in each test). The 3-dimensional positions of 12 cows with synchronized estrous cycles and 4 pregnant control cows were monitored continuously using UWB mobile units operating within a network of 8 base units for a period of 7d. In the study, 10 cows exhibited estrus as confirmed by visual observation, activity monitoring, and milk progesterone concentrations. Automated software was developed for analysis of UWB data to detect cows in estrus and report the onset of estrus in real time. The UWB technology accurately detected 9 out of 10 cows in estrus. In addition, UWB technology accurately confirmed all 6 cows not in estrus. In conclusion, UWB technology can accurately detect estrus and hence we have demonstrated proof of concept for a novel technology that has significant potential to improve estrus-detection rates. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Endocrine events during the periestrous period and the subsequent estrous cycle in ewes after estrus synchronization.

PubMed

Menegatos, J; Chadio, S; Kalogiannis, T; Kouskoura, T; Kouimtzis, S

2003-04-01

The aim of the present study was to investigate the endocrinology of the periestrus period and that of the subsequent estrous cycle in ewes synchronized during the breeding season. Animals were treated for 14 days with either MAP intravaginal sponges or subcutaneous progesterone implants, followed by administration of 500 IU PMSG at the time of withdrawal. The time to estrus occurrence following progestagen withdrawal differed significantly between groups (45.3+/-2.7h for the MAP and 21.5+/-1.2h for the implant group, P<0.001). Estradiol levels around estrus did not differ between groups, but a significant difference was detected for the interval from peak estradiol to estrus, with a shorter interval for the implant group (26.7+/-0.7 and 2.7+/-0.9h, P<0.001). Progesterone implants shortened the interval from removal to LH surge, compared to the MAP group (31.2+/-4.4 and 56.5+/-3.6h, respectively, P<0.05). An earlier response was also observed for the interval from estradiol peak to LH peak in the implant group (12.1+/-3.3 and 37+/-2h, respectively, P<0.005), but no difference was observed for the interval from estrus to LH surge. Progesterone levels, particularly during the Days 6 to 10 of the subsequent estrous cycle were significantly higher (P<0.05) in the implant group. It is concluded that the kind of progesterone treatment may affect the time of estrus and the LH peak as well as the progesterone levels of the subsequent cycle.

The relationship between external auditory canal temperature and onset of estrus and ovulation in beef heifers.

PubMed

Randi, Federico; McDonald, Michael; Duffy, Pat; Kelly, Alan K; Lonergan, Patrick

2018-04-01

The aim of this study was to evaluate the relationship of body temperature fluctuations, as measured by external auditory canal temperature, to the onset of estrus and ovulation. Beef heifers (n = 44, mean age 23.5 ± 0.4 months, mean weight 603.3 ± 5.7 kg) were fitted with a Boviminder ® ear tag 2 weeks before the start of the estrous synchronization protocol to allow acclimatization. The device recorded the temperature, accurate to 0.01° Fahrenheit, every 10 min and transmitted the data via a base station over the internet where it could be accessed remotely. The estrous cycles of all heifers were synchronized using an 8-day progesterone-based synchronization program; on day 0 a PRID was inserted in conjunction with an injection of GnRH, and PGF2α was administered the day before PRID removal. Heifers were checked for signs of estrus at 4-h intervals (i.e., 6 times per day) commencing 24 h after PRID withdrawal. Beginning 12 h after the onset of estrus, the ovaries were ultrasound scanned at 4-h intervals to determine the time of ovulation. Body temperature was recorded every 10 min and averaged to hourly means for the following 4 periods relative to the detected oestrus onset (=Time 0): Period I: -48 h to -7 h, Period II: -6 h to +6 h, Period III +7 h to ovulation, and Period IV: ovulation to 48 h post ovulation. Data were analysed using a Mixed Model ANOVA in SAS in a completely randomized design to observe effects of induced estrus on external auditory canal temperature. The mean (±SD) interval from removal of the PRID to onset of estrus activity was 46.6 ± 14.7 h. The mean duration of estrus was 16.0 ± 5.67 h and the mean interval from estrus onset to ovulation was 27.9 ± 7.68 h. Highest temperatures (100.95 ± 0.03 °F) were observed in Period II around estrus onset, whereas lowest temperatures were observed in the 48 h preceding estrus onset (100.28 ± 0.03 °F; Period I) and around ovulation (100.30 ± 0.2 °F; Period III)(P < .001). Indeed, around the time of estrus onset (Period II) mean temperature was 0.66 °F (P < .001) higher compared with Period I. Diurnal temperature rhythms were similar (P > .10) before (Period I) and after oestrus (Period III). In conclusion, a significant elevation in external auditory canal temperature was associated with estrus in beef heifers and was followed by a decline in temperature leading up to ovulation approximately 28 h later. Future studies are required to assess pregnancy rates following AI based on changes in external auditory canal temperature. Copyright © 2018 Elsevier Inc. All rights reserved.

Estrus resynchronization in ewes with unknown pregnancy status.

PubMed

Miranda, Vladinis O; Oliveira, Fernando C; Dias, Jenniffer H; Vargas Júnior, Sergio F; Goularte, Karina L; Sá Filho, Manoel F; Sá Filho, Ocilon G de; Baldassarre, Hernan; Vieira, Arnaldo D; Lucia, Thomaz; Gasperin, Bernardo G

2018-01-15

Although fixed-time artificial insemination (FTAI) protocols are available for sheep, estrus resynchronization has not been previously reported. The objectives of this study were to evaluate the effect of estrus resynchronization with exogenous progestogen on endogenous progesterone levels and to compare pregnancy rates after two consecutive estrus synchronizations in ewes. In Experiment 1, ewes (n = 20) received an intravaginal device (IVD) containing 60 mg medroxyprogesterone acetate (MPA) for 10 days. At the IVD withdrawal (D0), ewes received 250 IU eCG and were allocated into two treatments: either no further treatment (Control; n = 10) or estrus resynchronization (Resynch; n = 10) from D12 to D19. Serum progesterone (P4) levels did not differ at D12 and D19 (P > 0.05), but were greater at D15 for the Control compared with the Resynch group (P < 0.05). In experiment 2, ewes (n = 250) were submitted to a first synchronization protocol followed by estrus detection and either artificial insemination (AI) or natural mating (NM). Subsequently, ewes were divided into two groups: Control (n = 104): which received no further treatment and were bred by NM; and Resynch (n = 146): which were submitted to a second synchronization starting on D14 (first IVD withdrawal = D0) and to NM after second IVD withdrawal (D20). Cumulative pregnancy rates did not differ between the Control (67.3%, 70/104) and Resynch (62.3%, 91/146) groups. In a third experiment, ewes (n = 83) were bred by two consecutive FTAI within a 20-day interval. Pregnancy rates after the first (30.1%, 25/83) and the second FTAI (36.2%, 21/58) did not differ (P > 0.05). In conclusion, although exogenous progestogen supplementation reduced circulating levels of P4, pregnancy maintenance was unaffected. Estrus resynchronization in ewes is feasible, resulting in similar fertility after the first and the second services. The use of resynchronization coupled with artificial insemination using semen from genetically superior rams may potentially accelerate genetic improvement in sheep herds by allowing a higher differential selection compared with natural breeding. Copyright © 2017 Elsevier Inc. All rights reserved.

A review of current timed-AI (TAI) programs for beef and dairy cattle

PubMed Central

Colazo, Marcos G.; Mapletoft, Reuben J.

2014-01-01

This is a review of the physiology and endocrinology of the estrous cycle and how ovarian physiology can be manipulated and controlled for timed artificial insemination (TAI) in beef and dairy cattle. Estrus detection is required for artificial insemination (AI), but it is done poorly in dairy cattle and it is difficult in beef cattle. Protocols that synchronize follicle growth, corpus luteum regression and ovulation, allowing for TAI, result in improved reproductive performance, because all animals are inseminated whether they show estrus or not. As result, TAI programs have become an integral part of reproductive management in many dairy herds and offer beef producers the opportunity to incorporate AI into their herds. Gonadotropin-releasing hormone-based protocols are commonly used in North America for estrus synchronization as part of a TAI program. Protocols that increase pregnancy rates in lactating dairy cows and suckling beef cows have been developed. Protocols that improve pregnancy rates in heifers, acyclic beef cows, and resynchronized lactating dairy cows are also discussed. PMID:25082993

A review of current timed-AI (TAI) programs for beef and dairy cattle.

PubMed

Colazo, Marcos G; Mapletoft, Reuben J

2014-08-01

This is a review of the physiology and endocrinology of the estrous cycle and how ovarian physiology can be manipulated and controlled for timed artificial insemination (TAI) in beef and dairy cattle. Estrus detection is required for artificial insemination (AI), but it is done poorly in dairy cattle and it is difficult in beef cattle. Protocols that synchronize follicle growth, corpus luteum regression and ovulation, allowing for TAI, result in improved reproductive performance, because all animals are inseminated whether they show estrus or not. As result, TAI programs have become an integral part of reproductive management in many dairy herds and offer beef producers the opportunity to incorporate AI into their herds. Gonadotropin-releasing hormone-based protocols are commonly used in North America for estrus synchronization as part of a TAI program. Protocols that increase pregnancy rates in lactating dairy cows and suckling beef cows have been developed. Protocols that improve pregnancy rates in heifers, acyclic beef cows, and resynchronized lactating dairy cows are also discussed.

Developmental programming in sheep: administration of testosterone during 60-90 days of pregnancy reduces breeding success and pregnancy outcome.

PubMed

Steckler, T L; Roberts, E K; Doop, D D; Lee, T M; Padmanabhan, V

2007-02-01

Evidence suggests that exposure to excess steroids during critical periods of fetal development leads to reproductive disorders. Exposure of female lambs to excess testosterone (T) from Days 60 to 90 of gestation (T60-90; term, 147 days) delayed onset of the LH surge and resulted in to male-typical reproductive behavior. The objectives of this study were to test the ability of T60-90 ewes to mate, conceive and lamb during the first three breeding seasons (Years 1, 2 and 3). Pregnant Suffolk ewes were injected with T propionate in cottonseed oil (100mg, im twice weekly) or vehicle (control; C) from Days 60 to 90 of gestation. In Year 1, ewes (C=12, T60-90=12) were kept with a vasectomized ram for 3 months and markings/visual observation of copulations were recorded. Rams had paint applied to their chest to facilitate detection of estrus and mating. All C but only three T60-90 ewes were marked (P<0.001). All ewes were then estrus-synchronized with two injections of prostaglandin F2alpha (20mg, im) given 11 days apart and allowed to mate with a painted, fertile ram. Nine of 12 C and 4 of 12 T60-90 ewes (P=0.1) were mated. Based on estrus and long-term monitoring of progesterone, more C than T60-90 became pregnant (82 and 18%, respectively; P<0.01). In Year 2, to maximize ram exposure, two C and two T60-90 estrus-synchronized ewes were placed with a painted, fertile ram at a time and mated ewes were removed to a nearby pen to force mating with others. Twenty-four hour video monitoring revealed the rams mated more C than T60-90 ewes (83 and 25%, respectively; P=0.01). In both Years 1 and 2, the rams preferred C over T60-90 ewes; therefore in Year 3 rams were given access only to T60-90 ewes. Only four T60-90 estrus-synchronized ewes were placed with a painted ram at a time. Not given an option, 91% of the T60-90 ewes were marked resulting in 4 of 11 (36%; first-service pregnancy rate in the breeding herd was 91%) ewes becoming pregnant to the synchronized estrus. Collectively these studies showed that fertility in T60-90 females was severely compromised, even after overcoming ram preference for controls.

Protected fatty acid supplementation during estrus synchronization treatment on reproductive parameters of dairy goats.

PubMed

Oliveira, Juliana Dos Santos Kuhner; Fonseca, Jeferson Ferreira da; Souza-Fabjan, Joanna Maria Gonçalves; Esteves, Luciana Vieira; Feres, Luiz Fernando Rodrigues; Rodrigues, Carla Aparecida Florentino; Torres Filho, Rodolpho de Almeida; de Oliveira, Juliana; Brandão, Felipe Zandonadi

2017-02-01

This study evaluated the effect of the protected fatty acid inclusion during estrus synchronization on reproductive parameters. Goats (n = 32) received progestagen sponges for 6 days and 200 IU equine chorionic gonadotropin and 30 µg d-cloprostenol were given on Day 5. No difference was found among control (C), 1% protected fatty acid inclusion (C + 1%) or 4% protected fatty acid inclusion (C + 4%) groups, respectively, in estrus (100.0, 100.0 or 90.9%), estrus duration (31.6 ± 12.3; 43.2 ± 12.9 or 40.8 ± 14.1 h), animals ovulating (100.0, 90.0 or 100.0%) or ovulation rate (1.3 ± 0.5; 1.1 ± 0.3 or 1.2 ± 0.4). The interval from sponge removal to ovulation and from estrus to ovulation, respectively, were shorter for C + 4% (45.2 ± 8.0 h; 18.3 ± 11.0 h) compared with C (56.3 ± 12.6 h; 30.6 ± 10.5 h) or C + 1% (57.7 ± 8.7 h; 30.3 ± 11.1 h). The average ovulatory follicle diameter was smaller for C + 4% (6.2 ± 0.7 mm) than C (7.5 ± 0.8 mm), but similar to C + 1% (7.0 ± 1.5 mm). Insulin, insulin-like growth factor 1, glucose and progesterone concentrations were similar among groups. The inclusion of protected fatty acid during synchronization treatment promoted no benefits on ovulation rate, but 4% anticipated the ovulation time. © 2016 Japanese Society of Animal Science.

D-Cloprostenol enhances estrus synchronization in tropical hair sheep.

PubMed

Ramírez, Alejandro Alavez; Villalvazo, Victor Manuel Meza; Arredondo, Emmanuel Sosa; Ramírez, Hugo Alonso Ramírez; Sevilla, Héctor Magaña

2018-06-01

To compare the effects of PGF2α (dinoprost tromethamine) and D-cloprostenol in a two-dose protocol for estrus synchronization in hair sheep during breeding season in Yucatán, México, two experiments were conducted. In experiment 1, 61 cyclic hair sheep were divided into two groups: G1 (control n = 30), two doses of 50 μg of dinoprost tromethamine IM with 12 days between applications, and G2 (n = 31), two doses of 50 μg of D-cloprostenol IM at the same time interval. For determination of progesterone levels, 16 ewes from each group were randomly selected. In experiment 2, 70 cyclic hair sheep were assigned at the same treatments (G1 and G2, n = 35) and 48 h after the second application, the ewes in estrus were detected by two vasectomized rams. Sheep with detected estrus were inseminated, and 45 days after, pregnant animals were identified by ultrasonography. An exact Fisher's test was performed for the analysis of ewes in estrus (experiments 1 and 2) and number of pregnant ewes (experiment 2); for the comparison of time between end of treatment-estrus presentation, a survival analysis was used. Duration of estrus in hours was analyzed using a generalized mixed model (GLM) ANOVA whereas plasma progesterone concentrations were analyzed by non-linear regression. There were significant differences (P < 0.05) in the proportion of ewes in estrus upon treatments (G1, 57% vs G2, 87% and G1, 37.1% vs G2, 65.7% in experiments 1 and 2, respectively), and between the end of treatment-onset estrus interval (P < 0.01), survival curves showed the highest number of sheep in estrus between 40 and 48 h (G1, 43.7 + 8.05 h vs G2, 42.9 + 6.7 h, experiment 1). There were no significant differences (P > 0.05) in duration of estrus (G1, 42 + 6.1 h, vs G2, 41.1 + 11.2 h, experiment 1) and pregnancy in the ewes that presented estrus, and were inseminated (G1, 38.4% vs 52.1%, experiment 2). With regard to concentrations of progesterone, significant differences (P < 0.01) were found between treatments, and progesterone levels before the second application of D-cloprostenol were higher. In consideration of the results, it can be concluded that in a two-dose protocol of a luteolytic agent, more ewes presented estrus in response to D-cloprostenol compared to dinoprost tromethamine with similar pregnancy rates.

Expression of Na(+)/H(+) exchanger isoforms 1, 2, 3, and 4 in bovine endometrium and the influence of uterine pH at time of fixed-time AI of pregnancy success.

PubMed

Bolzenius, Jennifer K; Cushman, Robert A; Perry, George A

2016-08-01

Cows that exhibit estrus prior to fixed-time AI had increased sperm transport to the site of fertilization, and improved embryo quality on d 6 after insemination. Sperm transport is influenced by uterine pH, and research has reported that uterine pH decreased at onset of estrus, but must return to normal prior to ovulation. Therefore, the objectives of these studies were to investigate a possible mechanism for the regulation of uterine pH around the onset of estrus, and to determine if uterine pH at time of fixed-time AI influenced pregnancy success. In experiment 1, Angus-cross beef cows (n=40 and 28 in rep. 1 and 2, respectively) were synchronized with the PG 6-day CIDR protocol (PGF2α on d -9, GnRH and insertion of a CIDR on d -6, and PGF2α and CIDR removal on d 0). Cows were blocked by follicle size at time of CIDR removal, and uterine biopsies were collected at 0, 12, 24, 36, 48, 60 (Rep. 1), 72, 84, or 96h (Rep2) after CIDR removal, and total cellular RNA was extracted from all biopsies. Estrus was monitored by the HeatWatch Estrous Detection System. In experiment 2, 223 postpartum beef cows in 2 herds were synchronized with a fixed-time AI protocol (herd 1: n=97; CO-Synch plus CIDR protocol; herd 2: n=126; Co-synch protocol). Uterine pH was determined at time of AI (n=80 and 63 for herd 1 and 2, respectively), and estrus was monitored by visual estrus detection with the aid of an ESTROTECT estrous detection patches, and pregnancy was determined by transrectal ultrasonography. In experiment 1, there was a significant (P<0.01), quadratic relationship in expression of Na(+)/H(+) exchanger isoforms 1, 2, and 3 among animals that exhibited estrus, with expression greatest at time of CIDR removal, decreasing to the onset of estrus, and then increasing again following the onset of estrus. Among cows that did not exhibit estrus, the preceding relationship did not exist (P>0.46). In experiment 2, cows that had initiated estrus prior to fixed-time AI had decreased (P=0.01) uterine pH compared to cows that did not initiate estrus (6.78±0.03 and 6.89±0.03, respectively), and uterine pH at AI had an approximately linear effect on pregnancy success within the observed pH range. Furthermore, cows that initiated estrus prior to AI had increased (P=0.05) pregnancy success (52% vs. 38%) compared to cows that had not initiated estrus. In summary, expression of Na(+)/H(+) exchanger isoforms 1, 2, and 3 decreased after CIDR removal among cows that exhibited estrus, but did not change among cows that did not exhibit estrus. Additionally, as uterine pH decreased pregnancy success tended to increase (P=0.076, logistics regression). Thus, Na(+)/H(+) exchanger isoforms 1, 2, and 3 appear to be key regulators of uterine pH around the onset of estrus, and this change in uterine pH is critical for pregnancy success. Expression of Na(+)/H(+) exchanger isoforms 1, 2, and 3 decreased after CIDR removal among cows that exhibited estrus, but did not change among cows that did not exhibit estrus, and as uterine pH decreased, pregnancy success tended to increase. Copyright © 2016 Elsevier B.V. All rights reserved.

Evaluation of two progestogen-based estrous synchronization protocols in yearling heifers of Bos indicus × Bos taurus breeding.

PubMed

McKinniss, E N; Esterman, R D; Woodall, S A; Austin, B R; Hersom, M J; Thatcher, W W; Yelich, J V

2011-06-01

Yearling Bos indicus × Bos taurus heifers (n = 410) from three locations, were synchronized with either the Select Synch/CIDR+timed-AI (SSC+TAI) or 7-11+timed-AI (7-11+TAI) treatments. On Day 0 of the experiment, within each location, heifers were equally distributed to treatments by reproductive tract score (RTS; Scale 1-5: 1 = immature, 5 = estrous cycling) and body condition score. The 7-11+TAI treatment consisted of melengestrol acetate (0.5 mg/head/d) from Days 0 to 7, with PGF(2α) (25 mg im) on Day 7, GnRH (100 μg im) on Day 11, and PGF(2α) (25 mg im) on Day 18. The SSC+TAI heifers received the same carrier supplement (without MGA) from Days 0 to 7, and on Day 11 they were given 100 μg GnRH and an intravaginal CIDR (containing 1.38 g progesterone). The CIDR were removed on Day 18, concurrent with 25 mg PGF(2α) im For both treatments, estrus was visually detected for 1 h twice daily (0700 and 1600 h) for 72 h after PGF(2α), with AI done 6 to 12 h after a detected estrus. Non-responders were timed-AI and received GnRH (100 μg im) 72 to 76 h post PGF(2α). The 7-11+TAI heifers had a greater (P < 0.05) estrous response (55.2 vs 41.9%), conception rate (47.0 vs 31.3%), and synchronized pregnancy rate (33.5 vs 24.8%) compared to SSC+TAI heifers, respectively. Heifers exhibiting estrus at 60 h (61.7%) had a greater (P < 0.05) conception rate compared to heifers that exhibited estrus at ≤ 36 (35.3%), 48 (31.6%), and 72 h (36.2%), which were similar (P > 0.05) to each other. As RTS increased from ≤ 2 to ≥ 3, estrous response, conception rate, synchronized pregnancy rate, and 30 d pregnancy rate all increased (P < 0.05), irrespective of synchronization treatment. In conclusion, the 7-11+TAI treatment yielded greater synchronized pregnancy rates compared to SSC+TAI treatment in yearling Bos indicus × Bos taurus heifers. Copyright © 2011 Elsevier Inc. All rights reserved.

Short communication: estrus synchronization using progestogens or cloprostenol in tropical hair sheep.

PubMed

Alavez Ramírez, Alejandro; Arroyo Ledezma, Jaime; Montes Pérez, Ruben; Zamora Bustillos, Roberto; Navarrete Sierra, Luis Fernando; Magaña Sevilla, Hector

2014-12-01

The objective of the experiment was to compare the use of a PGF2α analogue (Cloprostenol) IM, with an intravaginal progestagen sponge, flurogestone acetate (FGA), and equine chorionic gonadotropin (eCG) IM application protocol. A total of 30 cyclical hair ewes (54.07 ± 0.5 kg live weight, body condition score 3.5 ± 0.5, and age 3 ± 1 years) were used. For the control group ewes (n = 15), intravaginal sponges (IS) impregnated with 20 mg of FGA were inserted for 12 days with 500 IU of eCG IM at sponges withdrawal. For the PG group ewes (Treatment group n = 15), two injections of Cloprostenol (75 mcg) were given 12 days apart. The presence of estrus was detected using two rams with 8 h interval beginning at the end of the treatment. Progesterone concentrations in blood were measured by solid phase radioimmunoassay. A student's t test was performed to analyze the duration of estrus and the interval between the ends of the treatment and the onset of estrus (ET-OE) presentation. Progesterone levels were compared with two-way ANOVA, with treatment, and day of menstrual cycle as fixed factors. Treatment costs ratio was calculated by dividing the total costs of FGA IS application between total costs of Cloprostenol application. Significant differences (P < 0.05) were found in the (ET-OE) interval and estrus duration. For the control group, estrus was presented at 30 + 8.2 h; in treatment group, at 44 h after the last application, duration of estrus was 54.9 + 8.34 h, and 41 + 1.83 h for the control and treatment group, pregnancy rates were 53.3 and 60.0 %, respectively. Significant differences (P < 0.001) were found from days 9 to 13 on Progesterone levels in both treatments. Treatment costs of Cloprostenol protocol were 2.63 cheaper than FGA including disposable material, biological products, and labor. It was concluded that Cloprostenol could be an effective tool in estrus synchronization in hair sheep in tropical areas.

Effects of altering the dose and timing of triptorelin when given as an intravaginal gel for advancing and synchronizing ovulation in weaned sows.

PubMed

Knox, R V; Taibl, J N; Breen, S M; Swanson, M E; Webel, S K

2014-08-01

Previous studies have shown that triptorelin gel (TG) given intravaginally in gel form is effective for advancing the time of ovulation in weaned sows. Three experiments were performed to determine the effects of altering the dose and timing of administration of intravaginal TG for advancing and synchronizing ovulation in weaned sows. In all experiments, estrus was detected twice or three times daily and ultrasound was performed to determine ovulation at 8-hour intervals. In experiment 1, sows (n = 131) received intravaginal gel containing 0 (Placebo), 25, 100, or 200 μg of TG at 96 hours after weaning and sows were inseminated on each day of standing estrus. Wean-to-estrus interval and duration of estrus were correlated (P < 0.0001) with estrus duration longer in TG (P < 0.05) compared with Placebo. More sows ovulated (P < 0.001) by 48 hours after treatment with 200 (81%), 100 (64%), and 25 μg (63%) of TG compared with Placebo (42%). The farrowing rate and total pigs born did not differ (P > 0.10). In experiment 2, sows (n = 126) received 200 μg of TG at 72, 84, or 96 hours after weaning or were untreated (Control-96). Sows receiving TG were inseminated once 24 to 28 hours after treatment. Control-96 sows were inseminated on each day of standing estrus. Wean-to-estrus interval was not affected by treatment, but wean-to-ovulation interval was reduced (P < 0.05) by TG-72 and TG-84 compared with TG-96 and Control-96. More sows ovulated 40 hours after treatment (P < 0.001) with TG-72 (56.5%) and TG-84 (32.2%) compared with TG-96 and Control-96 (13%) and for all TG treatments 48 hours after treatment (64%) compared with Control-96 (34%, P < 0.05). The farrowing rate was lower (P < 0.05) for sows assigned to TG-72 and TG-84 compared with TG-96 and Control-96, whereas the number of liveborn pigs did not differ (P > 0.10). In experiment 3, sows (n = 113) were assigned to receive no treatment (Control), intravaginal gel alone (Placebo), or 200 μg of TG given intravaginally (OvuGel) at 96 hours after weaning. Wean-to-estrus interval did not differ, but the duration of estrus tended (P < 0.10) to be reduced with OvuGel compared with the other treatments. More sows ovulated (P < 0.001) by 48 hours after OvuGel treatment (79.1%) compared with Control (46.4%) and Placebo (37.9%) and by 56 hours (P < 0.05). The farrowing rate and the number of liveborn pigs did not differ among treatments. The results of these studies indicate that 200 μg of TG given intravaginally at 96 hours after weaning (OvuGel) synchronizes ovulation and results in fertility similar to Controls. Copyright © 2014 Elsevier Inc. All rights reserved.

Recent advances in the synchronization of estrus and ovulation in dairy cows.

PubMed

Macmillan, Keith L

2010-01-01

Synchronization programs have become standard components in the current breeding management of cows in the dairy herds of most dairy industries. Many are based on protocols that allow timed inseminations (TAI) so as to circumvent the practical difficulties associated with estrus detection. These difficulties are exacerbated in modern herds of high producing cows either because of increasing herd size in which individual animal monitoring is difficult and often subjective, or because small intensively managed herds are milked in robotic systems that minimize animal: staff interactions. Additional reasons arise from high producing cows having less obvious symptoms of estrus, partly because of housing systems combined with intensive feeding and milking, partly because of higher metabolic clearance rates of reproductive hormones like estradiol and partly because of the increasing prevalence of prolonged post-partum anestrus and reproductive tract pathology. The most recently developed programs include protocols for resynchronization following first or subsequent inseminations. These re-synchronization protocols may involve selected forms of hormonal intervention during the diestrous and pro-estrous periods following TAI, or following pregnancy diagnosis by ultrasound from 28 days after TAI. The latter form of re-synchronization has become increasingly important with the recognition that late embryonic/early foetal death has become a major factor compromising the reproductive performance of high producing Holstein cows in many dairy industries. Although cows detected in estrus without any hormonal treatment before insemination have higher conception rates than those inseminated following synchronization and TAI, the low detection rates combined with embryonic death means that intervals from calving to conception (days open) are usually less when synchronization programs have been successfully implemented. One of the significant factors affecting a program's success is the compliance rate that may sometimes be less than 70%. Almost all programs involve strategically timed injections of prostaglandin F2alpha (PGF) and gonadotropin releasing hormone (GnRH). Injections of an estradiol ester and progesterone supplementation per vaginum may be included in some programs. The basic program is the "Ovsynch" regimen. Numerous variations have been tested and developed. Many involve increasingly complex protocols that increase the risk of non-compliance, none has consistently achieved conception rates that exceed 40% and few have reduced the incidence of embryonic death. These synchronization programs are the best that are currently available. They have not been able to overcome the consequences of lowered fertility associated with high levels of milk yield, forms of nutrition and environmental factors like heat stress that have profound effects on the physiology and metabolism of the high producing dairy cow.

Effect of preovulatory follicle maturity on pregnancy establishment in cattle: the role of oocyte competence and the maternal environment

USDA-ARS?s Scientific Manuscript database

Reproductive technologies to synchronize estrus and ovulation in cattle have enhanced the ability to practically utilize artificial insemination to increase both genetic merit and reproductive management of beef and dairy herds. The ability to successfully synchronize a follicular wave and ovulation...

Effects of physiological and/or disease status on the response of postpartum dairy cows to synchronization of estrus using an intravaginal progesterone device.

PubMed

McNally, Julie C; Crowe, Mark A; Roche, James F; Beltman, Marijke E

2014-12-01

Progesterone treatments are used to increase submission rates in postpartum dairy cows; however, in many cases the protocol is used as a blanket therapy for all cows without regard for physiological or disease state. The objective of this study was to identify the physiological or disease classes of cows that respond well (or not) to synchronization of estrus via progesterone. Dairy cows (n = 402) were monitored peri and postpartum to establish their physiological or disease status. Animals were classified as having negative energy balance, clinical lameness, uterine infection (UI), anovulatory anestrus, high somatic cell counts, and healthy (H). Blood samples were collected at five different time points and analyzed for metabolites. All animals received an 8-day controlled internal drug release protocol, which included GnRH at insertion and PGF2α the day before removal. Response to the protocol was determined by visual observation of estrus synchronization. Conception rate was determined by ultrasonography between Days 32 and 35 after artificial insemination. Animals without UI were 1.9 times more likely to respond and two times more likely to be confirmed pregnant than those with UI. There was no relationship between negative energy balance and clinical lameness in the visual estrous response, but both conditions were associated with reduced conception rates. Dairy cows in anovulatory anestrus responded successfully to the protocol in both estrous response and conception rates. High glutathione peroxidase concentrations had a positive effect on conception rates, whereas high non-esterified fatty acids and beta-hydroxybutyrate had a negative effect on the estrous response. In conclusion, disease and physiological states of dairy cows determined the response to progesterone-based synchronization. The more disease or physiological problems the cows had, the lower the estrous response and conception rates; cows with these problems were not ideal candidates for synchronization. Both anestrus and healthy dairy cows were good responders to progesterone-based synchronization. Copyright © 2014 Elsevier Inc. All rights reserved.

Use of fluorogestone acetate sponges or controlled internal drug release for estrus synchronization in ewes: Effects of hormonal profiles and reproductive performance.

PubMed

Swelum, Ayman Abdel-Aziz; Alowaimer, Abdullah Nasser; Abouheif, Mohamed Ahmed

2015-09-01

This study was carried out using 300 multiparous Najdi ewes during breeding season to compare the effects of fluorogestone acetate (FGA) sponges and controlled internal drug release (CIDR) dispensers to synchronize estrus on reproductive performance and hormonal profiles. Ewes were equally and randomly allotted into group A (FGA) and group B (CIDR); intravaginal progestagen was administered for 14-day period with intramuscular administration of 600-IU eCG at withdrawal time. Estrus was detected using a vasectomized ram starting 12 hours after progestagen withdrawal and repeated every 12 hours up to 84 hours. Blood samples were collected at the time of progestagen withdrawal (0 hour), 24 hours, and 48 hours. Follicle-stimulating hormone, LH, estradiol, and progesterone serum concentrations were measured using commercial ELISA kits and microtitrimetric plates. Timed laparoscopic insemination was performed 48 hours after progestagen withdrawal. Pregnancy and the number of fetuses were diagnosed by ultrasonography on Day 23 after insemination and confirmed on Days 35 and 60. The results revealed that the retention, vaginal discharge, and drawstring breakage rates after progestagen removal were significantly (P ≤ 0.05) higher in the FGA group (94.00, 98.58, and 9.22, respectively) than those in the CIDR group. On the other hand, pregnancy, fertility, twinning rates, and fecundity were significantly (P ≤ 0.05) higher in the CIDR group (77.86, 75.57, 34.34, and 1.02, respectively) than in the FGA group. Estrus responses in FGA and CIDR groups increased gradually to attain their significantly (P ≤ 0.05) higher percentages after 48 hours of progestagen withdrawal (91.49 and 92.37, respectively); thereafter, they decreased. The overall estrus responses and prolificacy did not differ between the FGA and CIDR groups. Follicle-stimulating hormone was significantly higher in the FGA group at 24 and 48 hours after progestagen withdrawal, whereas LH was significantly higher in the CIDR group at 48 hours after progestagen withdrawal. Estradiol and progesterone were significantly higher in the CIDR group at 0, 24, and 48 hours after progestagen withdrawal. These results indicated that although FGA and CIDR devices are efficient in synchronizing estrus in ewes, CIDR provided higher pregnancy, fertility, twinning rates, and fecundity than FGA. Copyright © 2015 Elsevier Inc. All rights reserved.

Efficiency of different hormonal treatments for estrus synchronization in tropical Santa Inês sheep.

PubMed

Texeira, Tarcísio Alves; da Fonseca, Jeferson Ferreira; de Souza-Fabjan, Joanna Maria Gonçalves; de Rezende Carvalheira, Luciano; de Moura Fernandes, Daniel Andrews; Brandão, Felipe Zandonadi

2016-03-01

The aim of this study was to evaluate the effect of (i) the duration of hormone treatment with progestogen sponges during the seasonal anestrus and (ii) the administration of two doses of prostaglandin at 7 days apart during the breeding season on reproductive parameters of Santa Inês ewes. In experiment 1, 32 ewes received intravaginal MAP sponges for 6 (G6 days), 9 (G9 days), or 12 (G12days) days and 75 μg D-cloprostenol i.m. and 300 IU eCG i.m. 1 day before sponge removal. In experiment 2, 23 ewes received two doses of 0.48-mg sodium cloprostenol i.m. 7 days apart. Ovarian follicular dynamic was assessed through transrectal ultrasonography. Blood samples were collected daily to determine progesterone concentrations. In experiment 1, estrus and ovulation rates did not differ (P > 0.05) among protocols and between cyclic and acyclic ewes at the beginning of the experiment. The G9 days treatment showed a lower dispersion of ovulations in relation to onset of estrus when compared to G6 days and G12 days. In experiment 2, all ewes exhibit estrus and ovulated after the second dose of prostaglandin, although ewes that were in diestrus at D0 showed subluteal concentrations of progesterone during the follicle development stage of the treatment. In conclusion, the use of progestogen device during 9 days promotes lower dispersion of ovulation when compared to its use for 6 or 12 days, and the protocol of two doses of prostaglandin 7 days apart synchronizes estrus efficiently but results in follicular development under low progesterone concentrations.

Differences in uterine immunoexpression of PR, ERα and OTR when comparing prostaglandin- to progestagen-based protocols for ovine estrus synchronization.

PubMed

Ruiz-González, I; Sánchez, M A; García-Palencia, P; Sánchez, B; García-Fernández, R A; González-Bulnes, A; Flores, J M

2012-07-01

The aim of this work was to compare PR, ERα and OTR uterine expression between days 9 and 21 of pregnancy in ewes whose estrus had been synchronized with two different protocols. Sixty-four adult Manchega ewes were synchronized with either conventional progestagens (P) or prostaglandin analogues (PG), and mated. Uterine samples were obtained from pregnant animals (group P, n=24; group PG, n=25) on days 9 post coitus (pc), 13pc, 15pc, 17pc and 21pc. Immunohistochemical detection of progesterone receptor (PR), estrogen receptor-α (ERα) and oxytocin receptor (OTR) was assessed in different uterine cell compartments including luminal and glandular epithelium, stroma and myometrium. Interaction day × treatment was obtained when assessing PR expression in the caruncular stroma (P=0.027) and myometrium (P=0.000), as well as for ERα in the superficial stroma (P=0.05). Significant "day post coitus" effect was found regarding to PR (P<0.01, with the exception of the superficial stroma, deep stroma and myometrium), ERα (P<0.01), and OTR (P<0.05, except in the deep compartments). No significant "treatment" effect was found for PR, ERα or OTR protein immunoexpression. This study supports the implication of PR, ERα and OTR within days 9-21 of the ovine pregnancy. Moreover, different expression pattern of PR and ERα proteins has been found between treatments in various compartments studied. Collectively, these results indicate that PR, ERα and OTR expression during early pregnancy is similar between ewes treated with either progestagens or prostaglandin analogues-based protocols for estrus synchronization. Copyright © 2012 Elsevier B.V. All rights reserved.

Dynamics of putative sex pheromone components during heat periods in estrus-induced cows.

PubMed

Mozūraitis, R; Kutra, J; Borg-Karlson, A-K; Būda, V

2017-09-01

Determination of the optimal insemination time in dairy cows is vital for fertilization success and is a challenging task due to silent or weak signs of estrus shown by some cows. This can be overcome by combining several estrus detection methods, leading to higher detection rates. However, an efficient, noninvasive method for detecting estrus in cows is still needed. Chemical cues released by the cow during estrus have been proposed to have pheromonal properties and signal readiness to mate to the bull. Such cues could be used in an industrial setting to detect cows in estrus. However, no conclusive published data show temporal changes in putative sex pheromone levels during estrus. The goal of this study was to determine the temporal pattern of putative sex pheromone components during estrus and to assess the reproducibility of changes in pheromone concentration with respect to ovulation time. Two injections of the hormone PGF 2α were administered over a 2-wk interval to induce and synchronize the estrous cycles of 6 Holstein cows. The precise time of ovulation was determined by means of an ultrasound technique, and estrus was determined by visual observation. Using solid-phase microextraction gas chromatography-mass spectrometry techniques, we showed that acetic and propionic acids, which have been proposed to be putative sex pheromone components in cows, were present in the headspaces of all estrous and diestrous fecal samples, whereas 1-iodoundecane was not detected by solid-phase microextraction or by solvent extraction with diethyl ether. Low levels of acids were observed until 1 d before ovulation, at which point their concentrations increased, peaking around 0.5 d before ovulation. The application of labeled synthetic standards revealed that during the peak of release, 36 ± 8 ng (average ± SD) of acetic acid and 10 ± 3 ng of propionic acid were present in 0.5-g samples of estrous-phase fecal matter compared with 19 ± 5 and 2.3 ± 1 ng of acetic and propionic acids, respectively, in the control diestrous samples. After the peak, the amounts of the compounds decreased sharply to match those of the control samples and afterward returned to the baseline readings. This decrease in the amounts of putative pheromone components was registered about 12 h before ovulation, indicating that acetic and propionic acids could be used as biomarkers for the electronic detection of ovulation. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Use of controlled internal drug releasing (CIDR) devices to control reproduction in goats: A review.

PubMed

Knights, Marlon; Singh-Knights, Doolarie

2016-09-01

High reproductive rates are necessary in order to increase the productivity of goat operations. Progesterone and its analogues are widely used in other species to control the reproductive system to facilitate synchronized births, induce fertile estrus or to facilitate the use of assisted reproductive techniques with the goal of increasing productivity of livestock. Progesterone impregnated controlled internal drug releasing (CIDR) devices are approved for delivery of the natural hormone progesterone to synchronize and induce fertile estrus in sheep. A few studies have reported a high estrous response and pregnancy rates when CIDRs are used to induce estrus in goats. However, significant variation exists in the duration of treatment (5-16 days) and in the use of exogenous gonadotropins as part of the treatment protocol. As gonadotropins are not currently approved for commercial use in small ruminants in the USA, studies are needed to determine the necessity for exogenous gonadotropins and whether they can be replaced by enhancing endogenous secretion through photoperiodic manipulation of the doe and \\ or increase stimulation through the 'buck-effect'. Future studies must not only evaluate efficacy, but should consider the economic feasibility of using CIDRs in commercial production systems. © 2016 Japanese Society of Animal Science.

Estrus response and fertility of Menz and crossbred ewes to single prostaglandin injection protocol.

PubMed

Mekuriaw, Zeleke; Assefa, Habtemariam; Tegegne, Azage; Muluneh, Dagne

2016-01-01

Natural lambing in sheep in Ethiopia occurs throughout the year in a scattered manner negatively affecting survival and growth rates of the lambs born during the unfavorable season of the year. Thus, controlling the time of mating artificially using exogenous source of hormones is considered as one of the ways to mitigated problems related to haphazard lambing. To this end, an experiment was conducted to evaluate efficacy of prostaglandin-based estrus synchronization protocol in local and crossbred ewes. A total of 160 ewes (80 local and 80 crossbreds) which lambed at least once and aged 3-5 years were used. Lutalyse® (dinoprost tromethamine sterile solution equivalent to 5 mg dinoprost per ml) and its analog, Synchromate® (cloprostenol sodium equivalent to 0.250 mg cloprostenol per ml), were tested at different doses. The treatments used were intramuscular injection of (1) 2.50 ml of Lutalyse® (12.5 mg dinoprost tromethamine), (2) 2 ml of Lutalyse® (10.0 mg dinoprost tromethamine), (3) 1 ml of Synchromate® (0.25 mg of cloprostenol Sodium), and (4) 0.8 ml of Synchromate® (0.20 mg of cloprostenol Sodium). Forty ewes (20 local and 20 crossbreds) were allocated per treatment. Following injection of the respective hormones, rams of known fertility were introduced into the flock for the duration of 96 h at the ratio of one ram to 10 ewes. All estrus synchronization protocols except treatment 4 (0.8 ml of Synchromate®) induced estrus (heat) in majority (55-65%) of local and crossbred ewes within 96 h post-hormone injection. The time interval from hormone administration to onset of estrus was also more or less similar for all treatment groups except for treatment group 4 which showed heat quicker. The highest lambing rate was recorded in local ewes (84.62% (11/13) treated with 2.5 ml of Lutalyse®, whereas the least was obtained in crossbreds (33.33% (3/9) treated with 0.8 ml Synchromate®. In conclusion, even though 2.5 ml and 2 ml of Lutalyse® or 1 ml of Synchromate® were able to induce heat in majority of local and crossbred ewes, the highest lambing percentage was obtained from ewes treated with 2.5 ml of Lutalyse®. Therefore, the use of 2.5 ml Lutalyse® is recommended to synchronize estrus in local and crossbred ewes under Ethiopian smallholder sheep production system for the benefit of improved lambing rate.

21 CFR 522.850 - Estradiol valerate and norgestomet in combination.

Code of Federal Regulations, 2011 CFR

2011-04-01

.... (c) Conditions of use—(1) Amount. One implant and 2 milliliters of injection at time of implantation. (2) Indications for use. For synchronization of estrus/ovulation in cycling beef cattle and non...

21 CFR 522.850 - Estradiol valerate and norgestomet in combination.

Code of Federal Regulations, 2014 CFR

2014-04-01

.... (c) Conditions of use—(1) Amount. One implant and 2 milliliters of injection at time of implantation. (2) Indications for use. For synchronization of estrus/ovulation in cycling beef cattle and non...

21 CFR 522.850 - Estradiol valerate and norgestomet in combination.

Code of Federal Regulations, 2010 CFR

2010-04-01

.... (c) Conditions of use—(1) Amount. One implant and 2 milliliters of injection at time of implantation. (2) Indications for use. For synchronization of estrus/ovulation in cycling beef cattle and non...

21 CFR 522.850 - Estradiol valerate and norgestomet in combination.

Code of Federal Regulations, 2013 CFR

2013-04-01

.... (c) Conditions of use—(1) Amount. One implant and 2 milliliters of injection at time of implantation. (2) Indications for use. For synchronization of estrus/ovulation in cycling beef cattle and non...

21 CFR 522.850 - Estradiol valerate and norgestomet in combination.

Code of Federal Regulations, 2012 CFR

2012-04-01

.... (c) Conditions of use—(1) Amount. One implant and 2 milliliters of injection at time of implantation. (2) Indications for use. For synchronization of estrus/ovulation in cycling beef cattle and non...

Estrus synchronization in sheep with synthetic progestagens.

PubMed

Awel, Hayatu; Eshetu, Lisanework; Tadesse, Gebrehiwot; Birhanu, Alemselam; Khar, S K

2009-10-01

Sixteen female sheep of Degua breed were assigned to receive either the full dose of norgestomet ear implant and injectable solution containing norgestomet and estradiol valerate (n = 8) or half the dose (n = 8). The ear implants were removed in both groups on day 12. All ewes received an intramuscular administration of 500 IU PMSG at implant withdrawal. Synchronized ewes were individually hand mated twice at 48 and 60 hours after implant removal. One ewe in each group however refused mating on both occasions. Pregnancy diagnosis was conducted by bimanual external palpation 90 to 100 days post mating. The conception rates (3/7, 42.85%) and (5/7, 71.42%) were recorded in the two treatment groups, respectively. All eight ewes lambed between 145 to 153 days post mating. In group I ewes carried only singletons (prolificity rate 1.0) whereas in group II two ewes delivered twins, producing 7 lambs with prolificity rate of 1.4 (N.S). From this preliminary investigation it appears that the lower dose of norgestomet ear implants offers better option for estrus synchronization accompanied by higher fertility.

Effectiveness of a short-term treatment with progesterone injections on synchrony of lambing and fertility in tropical hair sheep.

PubMed

Knights, Marlon; Ramgattie, Reeza; Siew, Narendra; Singh-Knights, Doolarie; Bourne, Gregory

2011-06-01

The efficacy of using a low cost system for delivering progesterone as part of an estrous synchronization protocol in sheep was evaluated. In experiment 1, Barbados Black Belly ewes (n=34) and ewe lambs (n=35; 37.5±0.9 kg) were assigned to be untreated, control animals (C), or to receive PGF(2α) on d0 (PG), or receive two injections of progesterone (200mg, i.m. each) on D -5 and on D -2.5, prior to PGF(2α), on D 0 (2PPG). Treatment with 2PPG increased the proportion of animals lambing to the first service (P<0.05), an effect that was greater in ewe lambs than ewes (treatment × parity; P<0.05). The interval from ram introduction to lambing and the mean lambing day was less (P=0.04) in the 2PPG-treated animals compared to control animals. In Experiment 2, lactating ewes from experiment 1 (n=61) 60-85 days postpartum were assigned within parity and number of lambs reared to remain nursing (S; n=29) or weaned (W; n=32) 3 weeks prior to treatment with the 2PPG protocol. There was no effect of treatment on the proportion of animals lambing to the first service or overall, interval from ram introduction to lambing and lambing interval. An 8-month lambing interval was observed in ewes in which estrus was synchronized regardless of physiological state. In conclusion, the two-progesterone injection synchronization protocol may be used as a practical low cost and efficient method of synchronizing estrus to reduce the lambing interval and maximize productivity in tropical breeds of sheep. Copyright © 2011 Elsevier B.V. All rights reserved.

Effect of number of cows in estrus and confinement area on estrous behavior of beef cows.

PubMed

Floyd, L N; Lents, C A; White, F J; Wettemann, R P

2009-06-01

Mature Angus and Angus x Hereford cows were used to determine the effects of confinement area and number of cows in estrus on estrous behavior. During each of 2 replicates, 32 nonpregnant, nonlactating cows were maintained in a drylot (60 x 100 m) or in a pasture (12 ha). Estrous cycles were synchronized with 2 injections of PGF(2alpha) 10 to 14 d apart at the initiation of the experiment. Thereafter, PGF(2alpha) was administered between d 6 and 18 of the estrous cycle so that 1, 2 to 3, 4 to 6, or > or = 7 cows were in estrus at the same time. Concentrations of progesterone were quantified in plasma at treatment to ensure cows had a normal response to PGF(2alpha). Duration of estrus and the number of mounts received during estrus were recorded by HeatWatch. If any part of estrus for a cow occurred at the same time as estrus for another cow, the cow was considered to have concurrent estrus with the other cow. Cows in the drylot had a shorter (P < 0.02; 61.8 +/- 3.1 h) interval to estrus after PGF(2alpha) compared with cows on pasture (72.8 +/- 3.3 h). The interval to estrus was longer (P < 0.07) when cows were treated with PGF(2alpha) on d 10 to 13 (76.7 +/- 3.3 h) of the estrous cycle than when treated on d 6 to 9 (62.3 +/- 4.7 h) or d 14 to 18 (62.9 +/- 3.6 h). Increasing the number of cows concurrently in estrus increased the number of mounts each cow received per estrus (P < 0.001) and the duration of estrus (P < 0.01). When only 1 cow was in estrus, she received 11.0 +/- 6.2 mounts during 11.6 +/- 1.5 h. When > or = 7 cows were in estrus at the same time, each cow received 50.4 +/- 3.2 mounts during 17.3 +/- 0.8 h. Cows in drylot were in estrus longer (P < 0.04; 16.4 +/- 0.8 h) than cows on pasture (14.2 +/- 0.7 h). Duration of the longest interval between mounts received decreased (P < 0.002) as the number of cows in estrus at one time increased (5.3 +/- 0.7 h for 1 estrous cow; 2.6 +/- 0.3 h when > or = 7 cows were in estrus). We conclude that increasing the number of beef cows in estrus at the same time will increase the number of times a cow is mounted and the duration of estrus. The increase in estrous behavior associated with more cows in estrus could increase the number of estrous cows detected with infrequent visual observation.

[Suppression of cycling activity in sheep using parenteral progestagen treatment].

PubMed

Janett, F; Camponovo, L; Lanker, U; Hässig, M; Thun, R

2004-03-01

The objective of this study was to evaluate the effect of two synthetic progestagen preparations Chlormadinone acetate (CAP, Chronosyn, Veterinaria AG Zürich) and Medroxyprogesterone acetate (MPA, Nadigest, G Streuli & Co. Uznach) on cycling activity and fertility in sheep. A flock of 28 non pregnant white alpine sheep was randomly divided into three groups, A (n = 10), B (n = 9) and C (n = 9). During a period of 4 weeks the cycling activity was confirmed by blood progesterone analysis. Thereafter, the animals of group A were treated with 50 mg CAP, those of group B with 140 mg MPA and those of group C with physiological saline solution. All injections were given intramuscularly. Suppression of endogenous progesterone secretion lasted from 28 to 49 days (mean = 39 days) in group A and from 42 to 70 days (mean = 50 days) in group B. The synchronization effect of both preparations was unsatisfactory as the occurrence of first estrus was distributed over a period of 3 weeks in group A and 4 weeks in group B. These findings could also be confirmed by the lambing period which lasted 52 days in group A and 36 days in group B. Control animals lambed within 9 days due to the synchronizing effect of the ram. The first fertile estrus was observed 36 days (group A) and 45 days (group B) after the treatment. In group A all 10 animals and in groups B and C 8 of 9 ewes each became pregnant. Parenteral progestagen application with CAP and MPA is a simple, safe and reversible method of estrus suppression in the sheep. The minimal suppressive duration of 4 (CAP) and 5 weeks (MPA) is not sufficient when a period of 3 months (alpine pasture period) is desired.

Seasonality, estrous cycle characterization, estrus synchronization, semen cryopreservation, and artificial insemination in the Pacific white-sided dolphin (Lagenorhynchus obliquidens).

PubMed

Robeck, T R; Steinman, K J; Greenwell, M; Ramirez, K; Van Bonn, W; Yoshioka, M; Katsumata, E; Dalton, L; Osborn, S; O'Brien, J K

2009-08-01

The reproductive physiology of the Pacific white-sided dolphin, Lagenorhynchus obliquidens, was characterized to facilitate the development of artificial insemination (AI) using cryopreserved spermatozoa. Specific objectives were to: 1) describe reproductive seasonality of the Pacific white sided dolphins; 2) describe urinary LH and ovarian steroid metabolites during the estrous cycle; 3) correlate LH and ovarian steroidal metabolite patterns to ultrasound-monitored follicular growth and ovulation; and 4) assess the efficacy of synchronizing estrus, sperm collection/cryopreservation, and intrauterine insemination. Ovulations (64%, n=37) and conceptions (83%, n=18) occurred from August to October. Peak mean serum testosterone (24 ng/ml), cross-sectional testicular area (41.6 cm(2)), and sperm concentration (144.3 x 10(7) sperm/ml) occurred in July, August, and September respectively. Spermatozoa were only found in ejaculates from July to October. Estrous cycles (n=22) were 31 d long and were comprised of a 10 d follicular and 21 d luteal phase. Ovulation occurred 31.2 h after the onset of the LH surge and 19.3 h after the LH peak. Follicular diameter and circumference within 12 h of ovulation were 1.52 and 4.66 cm respectively. Estrus synchronization attempts with altrenogest resulted in 17 (22%) ovulatory cycles with ovulation occurring 21 d post-altrenogest. Ten AI attempts using cryopreserved semen resulted in five pregnancies (50%). The mean gestation length was 356 days (range 348-367). These data provide new information on the Pacific white-sided dolphin's reproductive physiology and collectively enabled the first application of AI in this species.

Split-time artificial insemination in beef cattle: I-Using estrous response to determine the optimal time(s) at which to administer GnRH in beef heifers and postpartum cows.

PubMed

Bishop, B E; Thomas, J M; Abel, J M; Poock, S E; Ellersieck, M R; Smith, M F; Patterson, D J

2016-09-01

Two experiments evaluated timing of GnRH administration in beef heifers and cows on the basis of estrous status during split-time artificial insemination (AI) after controlled internal drug release (CIDR) based protocols. In experiment 1, estrus was synchronized for 816 pubertal and prepubertal or peripubertal heifers using the 14-day CIDR-PGF2α (PG) protocol, and in experiment 2, estrus was synchronized for 622 lactating cows using the 7-day CO-Synch + CIDR protocol. For both experiments, estrus detection aids (Estrotect) were applied at PG, with estrus recorded at 66 and 90 hours after PG. Treatments were balanced across locations for heifers using reproductive tract score and weight; whereas for cows, treatments were assigned and balanced to treatment according to age, body condition score, and days postpartum. Timing of AI for heifers and cows was on the basis of estrus expression 66 hours after PG. Females in each treatment that exhibited estrus before 66 hours were inseminated at 66 hours, whereas AI was delayed 24 hours until 90 hours after PG for females failing to exhibit estrus before 66 hours. Females in treatment one received GnRH 66 hours after PG irrespective of estrus expression; however, in treatment 2, GnRH was administered coincident with delayed AI only to females not detected in estrus at 66 hours after PG. Among heifers, there was no effect of treatment on overall estrous response (P = 0.49) or AI pregnancy rate (P = 0.54). Pregnancy rate for heifers inseminated at 66 hours was not influenced by GnRH (P = 0.65), and there were no differences between treatments in estrous response during the 24 hours delay period (P = 0.22). Cows in treatment 2 had a greater (P = 0.04) estrous response during the 24-hour delay period resulting in a greater overall estrous response (P = 0.04), but this did not affect AI pregnancy rate at 90 hours (P = 0.51) or total AI pregnancy rate (P = 0.89). Pregnancy rate resulting from AI for cows inseminated at 66 hours was not influenced by GnRH (P = 0.50). In summary, when split-time AI was used with the 14-day CIDR-PG protocol in heifers or the 7-day CO-Synch + CIDR protocol in cows, administration of GnRH at AI to females that exhibited estrus before 66 hours after PG was not necessary. Furthermore, among heifers for which AI was delayed on the basis of failure to exhibit estrus before 66 hours after PG, timing of GnRH (66 vs. 90 hours after PG) was more flexible. Delayed administration of GnRH to 90 hours after PG coincident with AI for cows that failed to exhibit estrus before 66 hours improved overall estrous response; however, in this study, a corresponding increase in pregnancy rate resulting from AI was not observed. Copyright © 2016 Elsevier Inc. All rights reserved.

[Conception rate and embryo development in guinea pigs with synchronized estrus induced by progesterone implant].

PubMed

Ueda, H; Kosaka, T; Takahashi, K W

1994-01-01

Observations were made on the timing of mating and the pre-implantation development of fertilized eggs in guinea pigs synchronized by long-term progesterone treatment. Females received a subcutaneous implant of progesterone-filled silastic tubing for 14 days. Copulation was observed from the evening of day 4 to the morning of day 6 in 53 of 54 females (98%). Most of them (47/53, 89%) copulated on day 5 after removal of the tubing. Designating the day of copulation (day 5 after removal of the tubing) as day 0 of gestation, embryos collected from the genital tract were at the 4-cell, 8-cell, morula, and blastocyst stages on days 1, 3, 4 and 5 of gestation, respectively. Eggs were recovered at high incidence (85-100%) from days 1 to 5 of gestation. On day 6 gestation, no eggs were recovered from the genital tract, suggesting that implantation had occurred. The mean litter size (+/- S. D.) was 4.0 +/- 0.8 pups, which were born normally after a mean gestation period of 67 +/- 1 days in 7 synchronized females. Since the female guinea pigs synchronized by the long-term progesterone treatment had normal reproductive ability similar to that of cyclic females, this technique would make it possible to obtain animals at a scheduled time even in smaller-sized colonies. In addition, observations on the pre-implantation development of embryos in females with synchronized estrus might be a useful aid in the field of reproductive research.

Influence of short-term energy supplementation on estrus, ovarian activity, and blood biochemistry in Ossimi ewes synchronized with fluorogestone acetate in the subtropics.

PubMed

Senosy, W; Mahmoud, G B; Abdel-Raheem, Sh M

2017-01-15

The objective of this study was to evaluate if short-term high-energy diet treatments have any overstimulatory effects on ovarian function and metabolic status in Ossimi ewes synchronized with progesterone sponge. Thirteen ewes were divided into high-energy (HEG; n = 7) and normal-energy or control (NEG; n = 6) groups. Progesterone sponges were placed intravaginally for 14 days during the winter breeding season (December-February). Four days before the removal of the sponges, a high-energy diet (130% of maintenance) was fed to HEG, whereas NEG was offered maintenance diet throughout the experiment. Ovarian performance and progesterone, estradiol, and blood metabolites were assessed daily starting from the day of removal of the sponges. Estrus period was longer in HEG (P < 0.05) when compared with NEG. Ovulation took place considerably longer with larger ovulatory follicles in HEG (P < 0.05). A marked increase in the level of total protein, albumin, glucose, and blood urea during the first 2 days following the removal of progesterone sponge was noticed in HEG when compared with NEG ewes. Eighty-five percentage (85.7%; 6/7) and 66.6% (4/6) had ovulation for the HEG and NEG, respectively. Dietary energy had a nonsignificant effect on the number of the recruited follicles, whereas a significant effect was observed for the diameter of the ovulatory follicle and ovulation rate (HEG, 2.3 ± 0.1 vs. NEG, 1.2 ± 0.3). It is concluded that short-term energy supplementation improves estrus expression and ovarian activity in fluorgestone acetate (FGA)-synchronized Ossimi ewes. Copyright © 2016 Elsevier Inc. All rights reserved.

Incidence of premature estrus in lactating dairy cows and conception rates to standing estrus or fixed-time inseminations after synchronization using GnRH and PGF(2alpha).

PubMed

DeJarnette, J M; Salverson, R R; Marshall, C E

2001-07-03

Fixed-time AI (TAI) after GnRH-PGF(2alpha)-GnRH treatment is a method to achieve pregnancies in dairy herds without estrous detection. However, cows that fail to respond to the initial GnRH may have compromised TAI conception rates due to asynchronous ovarian response. This study documented the percentage of GnRH-treated Holstein cows (n=345) in two herds that displayed estrus at an inopportune time for optimum TAI conception rate (< or =48h post-PGF(2alpha); premature estrus (PE)) and compared conception rates of two TAI protocols in cows that did not display PE. At biweekly herd health exams, cows diagnosed as not pregnant to a previous AI and cows >80 days postpartum with no AI were treated with 100 microg GnRH (day -7) and 25mg PGF(2alpha) (day 0). Cows detected in PE by twice-daily visual observation from day -7 to day 2 were bred by AI 8-12h later. Cows not detected in PE were randomly assigned by parity, body condition score, and postpartum interval to receive either: (1) 100microg GnRH at 48h after PGF(2alpha) and TAI 16 to 18h later (Ovsynch); or (2) TAI at 72h post-PGF(2alpha) and a concurrent 100 microg GnRH injection to those cows not detected in estrus between 48 and 72h post-PGF(2alpha) (modified Ovsynch (MOV)). All hormone injections were im. Twenty percent (68/345) of the cows were detected in estrus before 48 after PGF(2alpha), of which 5% (17/345) were detected in estrus before PGF(2alpha) (< or =day 0). Herd influenced the percentage of cows in the PE group (herd A versus herd B; 25% versus 14%; P<0.05). Conception rates were not affected by treatment (PE versus Ovsynch versus MOV; 32% (21/65) versus 30% (37/125) versus 32% (47/145); P>0.10). However, within MOV-treated cows, conception rates were greater (P<0.05) in cows detected in estrus (46% (23/50)) compared with cows not detected in estrus (25% (24/95)). In conclusion, 20% of GnRH-treated cows displayed PE and necessitates estrous detection during this period if maximal pregnancy rates are to be achieved. Although additional estrous detection is required compared to Ovsynch, reduced cow handling and hormone usage, efficient use of expensive semen through greater conception rates in cows detected in estrus, and comparable TAI conception rates, suggests the MOV protocol may be a cost effective alternative to Ovsynch in many dairy herd reproductive management programs.

Increased conception rates in beef cattle inseminated with nanopurified bull semen

USDA-ARS?s Scientific Manuscript database

Reproductive performance is of paramount importance to the cattle industry. Since recent progress has been achieved by optimizing estrus and ovulation synchronization protocols in cows, improvements are desired to increase the fertility of bulls enrolled in artificial insemination (AI) programs. Thi...

Enhance of the estrus and ovulation sychronism in ewes using protocols with progesterone

USDA-ARS?s Scientific Manuscript database

Estrous synchronization in combination with artificial insemination is an important biotechnology that enables greater and more efficient use of cryopreserved germplasm. However, when using this technology fertility rates after fixed-time artificial insemination (FTAI) still exist because of variati...

Vaginal mucus from ewes treated with progestogen sponges affects quality of ram spermatozoa.

PubMed

Manes, Jorgelina; Ríos, Glenda; Fiorentino, María Andrea; Ungerfeld, Rodolfo

2016-03-15

The use of intravaginal sponges (IS) to synchronize estrous onset in ewes provokes vaginitis, an increase in the vaginal bacterial load, and growth of bacterial species that are not present during spontaneous estrous behavior. The objective of the study was to compare the functional sperm parameters after incubating it with mucus collected from the vagina of ewes during spontaneous estrus or estrous synchronized with IS. Pooled spermatozoa were co-incubated with: (1) vaginal mucus collected from ewes in spontaneous estrus; (2) vaginal mucus collected from ewes in estrus pretreated with progestogen-impregnated IS; (3) synthetic mucus; and (4) medium without mucus as a control group. Sperm samples were evaluated after incubating it for 30 and 90 minutes. The number of colony-forming units (CFUs/mL), pH, and osmolality were greater in the mucus collected from ewes treated with IS than from those untreated (P = 0.046; P < 0.0001, and P < 0.0001, respectively). The percentage of sperm with progressive motility was lower after incubation with vaginal mucus collected from estrous ewes treated with IS than in the other three treatments both, 30 and 90 minutes after incubation (P = 0.0009 and P < 0.0001, respectively). The sample incubated for 30 minutes with mucus from ewes treated with IS had a lower percentage of sperm with intact plasma membrane than all the other treatments (P < 0.0001). The percentage of sperm with functional membrane was significantly lower in the sample incubated for 30 minutes with vaginal mucus from ewes treated with IS than in the other three treatments (P < 0.0001). After 90 minutes, the percentage was still lower than that in the sample collected from ewes during their spontaneous estrus (P = 0.0005). The lowest percentages of sperm with acrosome damage were observed in sperm incubated with mucus collected from sheep in spontaneous estrus for 30 and 90 minutes (P < 0.0001 and P = 0.008, respectively). The percentage of apoptotic spermatozoa was greater in samples incubated during 30 minutes with vaginal mucus collected from ewes treated with IS than in the other three groups (P = 0.0005). The functionality and the viability of ram sperm is negatively affected by the cervical mucus of ewes pretreated with progestagen-impregnated IS used in estrous synchronization treatments. This may partially explain the decrease in conception rate obtained with treatments with IS. Copyright © 2016 Elsevier Inc. All rights reserved.

21 CFR 522.914 - Fenprostalene solution.

Code of Federal Regulations, 2010 CFR

2010-04-01

... this chapter. (d) Special considerations. Labeling shall bear the following statements: Women of.... Feedlot heifers to induce abortion, single dose. Beef or nonlactating dairy cattle for estrus synchronization, a single dose or two doses 11 to 13 days apart. Do not use in pregnant animals unless abortion is...

Effect of different dietary energy level intakes on efficiency of estrus synchronization and fertility in Mashona goat does.

PubMed

Kusina, N T.; Chinuwo, T; Hamudikuwanda, H; Ndlovu, L R.; Muzanenhamo, S

2001-03-01

The objective of the study was to determine the effects of three dietary energy levels: 0.27 (low level: LL); 0.53 (medium level: ML), and 1.06 (high level: HL) MJMEkg(-1)W(0.75) on estrus synchronization and fertility in Mashona goat does. Forty-five multiparous Mashona goat does of average bodyweight 19.9+/-2.5kg were randomly allocated in equal numbers to the three dietary energy levels. The diets were made from a complete feed ration providing 9.83MJMEkg(-1)DM and 15.5% CPkg(-1)DM. Does were fed initially during a 60-day pre-synchronization period, and blood samples were collected twice a week for the determination of plasma progesterone concentrations to ascertain ovarian activity. Intramuscular injections of cloprostenol (100µg each) were administered 11 days apart. Immediately after the second injection of cloprostenol, three fertile bucks were introduced to the does and were left with the does for 21 days. The does were maintained on their dietary treatments throughout gestation except for those does in the LL treatment. Pregnancy was diagnosed 90 days post-mating using an ultrasound scanner. After pregnancy diagnosis, does on the LL treatment were randomly allocated to ML (n=7) and HL (n=8) treatments. During the pre-synchronization period, does on the LL treatment lost 12.3% whereas those on ML and HL treatments gained 2.1 and 28.8% of their initial bodymasses, respectively. The proportion of does exhibiting overt estrus within 96h after the last cloprostenol injection was significantly lower (P<0.05) for does on the LL treatment (60%) than for those on ML (93%) or HL (100%) treatments, respectively. However, based on plasma progesterone concentrations, the percentage of does on the LL treatment that exhibited ovarian cycles was numerically lower than that of does that were bred (40 versus 73%). Conception, fecundity and twinning rates were significantly lower (P<0.05) on the LL treatment than on the ML and HL treatments. These results indicate that feeding Mashona goat does 0.27MJMEkg(-1)W(0.75) compared to 0.53 and 1.06MJMEkg(-1)W(0.75) reduces the expression of estrus, conception, fecundity and twinning rates, and that feeding 0.53MJMEkg(-1)W(0.75) suffices for optimum reproduction. In addition, the results suggest that cloprostenol administration may induce ovarian cycles in reproductively quiescent does on dietary energy restriction.

Use of progestagen-gonadotrophin treatments in estrus synchronization of sheep.

PubMed

Boscos, C M; Samartzi, F C; Dellis, S; Rogge, A; Stefanakis, A; Krambovitis, E

2002-10-15

The main objective of this study was to investigate the effectiveness of certain progestagen-gonadotrophin treatments on synchronization of estrus in sheep. In Experiment I, 30 Chios ewes were treated at the beginning of the breeding season with medroxyprogesterone acetate (MAP) intravaginal sponges for 12 days and a single i.m. treatment of either FSH (Group 1,10 IU, n = 8; Group 2, 5 IU, n = 8; Group 3, 2.5 IU, n = 8) or eCG (Group 4, 400 IU, n = 6) at the time of sponge removal. Ten days after sponge removal laparotomy was performed to record ovarian response. Clinical estrus was observed in more (though not at a significant level) FSH treated than eCG treated sheep (62.5% versus 33.3%). Administration of 400 IU eCG resulted in the highest mean number of CL perewe ovulating (2.8 +/- 0.2), with administration of 10 IU FSH producing the next best results (2.1 +/- 0.3). Statistically significant differences in the mean number of CL per ewe ovulating were found only between ewes in Group 3 (1.7 +/- 0.4) and Group 4 (2.8 +/- 0.2) (P < 0.05). In Experiment II, 53 Chios and 30 Berrichon ewes were treated during the mid-breeding season with MAP intravaginal sponges for 12 days and a single i.m. treatment of either 10 IU FSH (27 Chios and 16 Berrichon ewes) or 400 IU eCG (26 Chios and 14 Berrichon ewes), at the time of sponge removal. Ewes that were in estrus on Days 2-4 and 19-23 after sponge removal were mated to fertile rams. No significant differences were recorded between treatment or breed groups in the proportions of ewes observed in estrus after treatment. In the Berrichon breed, FSH administration resulted in higher lambing rates (93.8% versus 57.1%, P < 0.05) and higher mean number of lambs born per ewe exposed to rams (1.4 +/- 0.2 versus 0.8 +/- 0.2, P < 0.05) than that of eCG. After treatment with eCG, the mean number of lambs born per ewe exposed to rams was higher in the Chios than the Berrichon breed (1.4 +/- 0.2 versus 0.8 +/- 0.2, P < 0.05). After treatment with FSH, the lambing rate was higher in the Berrichon than the Chios breed (93.8% versus 63.0%, P < 0.05). In conclusion, a single FSH treatment (5 or 10 IU) at the end of progestagen treatment appears to be more effective than eCG for the induction of synchronized estrus in sheep at the beginning of the breeding season, with no cases of abnormal ovarian response observed. During the mid-breeding season FSH (10 IU) appears to be equally as effective as eCG (400 IU) in respect of lambing rate and mean number of lambs born per ewe.

Effects of flunixin meglumine on pregnancy establishment in beef cattle

USDA-ARS?s Scientific Manuscript database

The objective of this research was to determine effects of a single injection of the prostaglandin synthesis inhibitor Flunixin Meglumine (FM; 1.1 mg/kg BW, i.m.) approximately 13 d after AI on pregnancy establishment. Three experiments were conducted using estrus-synchronized heifers and cows. Te...

Effect of P.G. 600 on the timing of ovulation in gilts treated with altrenogest.

PubMed

Horsley, B R; Estienne, M J; Harper, A F; Purcell, S H; Baitis, H K; Beal, W E; Knight, J W

2005-07-01

We previously reported that ovulation rate, but not pregnancy rate or litter size at d 30 after mating, was enhanced by treatment with P.G. 600 (400 IU of PMSG and 200 IU of hCG, Intervet America, Inc., Millsboro, DE) in gilts fed the orally active progestin, altrenogest (Matrix, Intervet America, Inc.) to synchronize estrus. We hypothesized that in addition to increasing ovulation rate, P.G. 600 may have altered the timing of ovulation. Therefore, mating gilts 12 and 24 h after first detection of estrus, as is common in the swine industry, may not have been the optimal breeding regimen, and as a consequence, pregnancy rate and litter size were not altered. The objective of the present study was to determine the effect of P.G. 600 on the timing of ovulation in gilts treated with altrenogest. Randomly cycling, crossbred gilts (5.5 mo old, 117 kg BW, and 14.7 mm of backfat) were fed a diet containing altrenogest (15 mg/d) for 18 d. Twenty-four hours after altrenogest withdrawal, gilts received i.m. injections of P.G. 600 (n = 25) or saline (n = 25). Gilts were checked for estrus at 8-h intervals. After first detection of estrus, transrectal ultrasonography was performed at 8-h intervals to determine the time of ovulation. Gilts were killed 9 to 11 d after the onset of estrus to determine ovulation rate. All gilts displayed estrus by 7 d after treatment with P.G. 600 or saline. Compared with saline, P.G. 600 increased (P = 0.07) ovulation rate (14.8 vs. 17.5, respectively; SE = 1.1). The intervals from injection to estrus (110.9 vs. 98.4; SE = 2.7 h; P < 0.01) and injection to ovulation (141.9 vs. 128.6; SE = 3.2 h; P < 0.01) were greater in gilts treated with saline than in gilts treated with P.G. 600. Duration of estrus (54.4 vs. 53.7; SE = 2.5 h), the estrus-to-ovulation interval (30.2 vs. 31.7; SE = 2.2 h), and the time of ovulation as a percentage of estrus duration (55.8 vs. 57.5; SE = 3.0%) did not differ for the P.G. 600 and saline-injected gilts, respectively. In summary, P.G. 600 advanced the onset of estrus and ovulation following termination of altrenogest treatment and increased ovulation rate; however, treatment of gilts with P.G. 600 had no effect on the timing of ovulation relative to the onset of estrus.

Behavioral and physiological changes around estrus events identified using multiple automated monitoring technologies.

PubMed

Dolecheck, K A; Silvia, W J; Heersche, G; Chang, Y M; Ray, D L; Stone, A E; Wadsworth, B A; Bewley, J M

2015-12-01

This study included 2 objectives. The first objective was to describe estrus-related changes in parameters automatically recorded by the CowManager SensOor (Agis Automatisering, Harmelen, the Netherlands), DVM bolus (DVM Systems LLC, Greeley, CO), HR Tag (SCR Engineers Ltd., Netanya, Israel), IceQube (IceRobotics Ltd., Edinburgh, UK), and Track a Cow (Animart Inc., Beaver Dam, WI). This objective was accomplished using 35 cows in 3 groups between January and June 2013 at the University of Kentucky Coldstream Dairy. We used a modified Ovsynch with G7G protocol to partially synchronize ovulation, ending after the last PGF2α injection (d 0) to allow estrus expression. Visual observation for standing estrus was conducted for four 30-min periods at 0330, 1000, 1430, and 2200h on d 2, 3, 4, and 5. Eighteen of the 35 cows stood to be mounted at least once during the observation period. These cows were used to compare differences between the 6h before and after the first standing event (estrus) and the 2wk preceding that period (nonestrus) for all technology parameters. Differences between estrus and nonestrus were observed for CowManager SensOor minutes feeding per hour, minutes of high ear activity per hour, and minutes ruminating per hour; twice daily DVM bolus reticulorumen temperature; HR Tag neck activity per 2h and minutes ruminating per 2h; IceQube lying bouts per hour, minutes lying per hour, and number of steps per hour; and Track a Cow leg activity per hour and minutes lying per hour. No difference between estrus and nonestrus was observed for CowManager SensOor ear surface temperature per hour. The second objective of this study was to explore the estrus detection potential of machine-learning techniques using automatically collected data. Three machine-learning techniques (random forest, linear discriminant analysis, and neural network) were applied to automatically collected parameter data from the 18 cows observed in standing estrus. Machine learning accuracy for all technologies ranged from 91.0 to 100.0%. When we compared visual observation with progesterone profiles of all 32 cows, we found 65.6% accuracy. Based on these results, machine-learning techniques have potential to be applied to automatically collected technology data for estrus detection. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The effect of numbers of frozen-thawed boar sperm and addition of prostaglandin F2α at insemination on fertility in pigs.

PubMed

Knox, Robert V; Yantis, Brandon M

2014-12-30

Frozen-thawed boar sperm (FTS) has reduced fertility compared to liquid semen. Exogenous prostaglandin administered at insemination has been reported to improve cases of low fertility. This experiment tested the effect of number of FTS and addition of prostaglandin (PGF2α) on fertility. The experiment was performed in replicates using weaned sows (n=24) and synchronized gilts (n=94). All females were induced into estrus using PG600® at weaning or following estrus synchronization. At estrus, females received 0.5, 1.0, or 2 billion motile FTS (n=9 boars) with 0 or 5mg of PGF2α added into each AI dose at insemination. Inseminations occurred at 24 and 36h after onset of estrus and ovulation was monitored by ultrasound. Pregnancy and litter size were determined for sows at farrowing and d 50 of gestation for gilts at slaughter. There was no effect of PGF2α and no interaction with dose of FTS or parity on fertility (P>0.10). Pregnancy rate was affected by FTS dose (P<0.001) with 2.0×10(9) (76.3%) greater than 0.5×10(9) (46.2%) and 1.0×10(9) sperm (48.8±8.0%). Pregnancy rate was not affected by parity (P>0.10) but was influenced by boar (P<0.05). Number of fetuses was also affected by FTS dose (P<0.001) with 2.0×10(9) (10.1) and 1.0×10(9) (9.4) producing more pigs than 0.5×10(9) sperm (6.9±0.9). Litter size was also affected by parity (P=0.001) and boar (P<0.01). These results indicate that AI using 2.0×10(9) FTS can result in acceptable pregnancy rates and litter sizes but with no measurable benefit for addition of prostaglandin. Copyright © 2014 Elsevier B.V. All rights reserved.

Effect of feed flushing during summer season on growth, reproductive performance and blood metabolites in Malpura ewes under semiarid tropical environment.

PubMed

Naqvi, Syed Mohammad Khursheed; Sejian, Veerasamy; Karim, Shaikh Abdul

2013-01-01

Feed scarcity during hot summer months is one of the major predisposing factors for low reproductive efficiency of livestock reared in hot semiarid environment. A study was conducted to assess the effect of concentrate supplementation during summer months on growth, reproductive performance, and blood metabolites in Malpura ewes. Twenty adult Malpura ewes were used in the present study. The ewes were divided into two groups viz, group 1 (n = 10; control) and group 2 (n = 10; concentrate supplementation). The study was conducted for a period of 35 days covering two estrus cycles. In the first cycle, only PGF(2α) was given to all ewes, while in second cycle, all ewes were synchronized for estrus using progesterone-impregnated intravaginal sponges and pregnant mare serum gonadotropin. The animals were allowed for grazing for 8-10 h per day. Apart from grazing, group 2 ewes were supplemented with concentrate mixture at 1.5 % of body weight. Concentrate supplementation had significant influence on body weight, ADG, estrus percentage, estrus duration, onset of estrus, ovulation response, plasma glucose, total protein, and urea. The present study reveals that ewes supplemented with concentrate mixture at 1.5 % of body weights during summer season significantly influenced the growth and reproductive performance of Malpura ewes. Further, the study signifies the importance of providing additional feed supplementation to ewes kept grazing under the conditions of a hot, semiarid environment to improve their reproductive efficiency.

Estrus synchronization in microminipig using estradiol dipropionate and prostaglandin F2α

PubMed Central

NOGUCHI, Michiko; IKEDO, Tomonobu; KAWAGUCHI, Hiroaki; TANIMOTO, Akihide

2016-01-01

The induction of pseudopregnancy by the exogenous administration of estradiol dipropionate (EDP) was investigated in cyclic Microminipigs (MMpigs) and the effects of exogenous administration of prostaglandin (PG) F2α on estrus exhibition were assessed in pseudopregnant MMpigs. In experiment 1, ovariectomized MMpigs were given a single intramuscular injection of 0.5, 1.5, or 2.5 mg of EDP. The estradiol-17β level at each of these doses was significantly higher 1 to 3 days after EDP administration than on the day of the injection. In experiment 2, animals were given 1.5 mg of EDP once at 9 to 12 days after the end of estrus (D0) and then no (1.5 mg × 1 group), one (D0 and D4; 1.5 mg × 2 group), or two (D0, D4 and D7; 1.5 mg × 3 group) additional treatments. The pseudopregnancy rate was significantly higher in the 1.5 mg × 3 than in the 1.5 mg × 1 group. In experiment 3, PGF2α was administered twice between 26 and 28 days after EDP treatment to five pseudopregnant gilts with a 24-h interval between the two injections. Estrus after PGF2α treatment and LH surge were observed in 100% and 80% pseudopregnant MMpigs, respectively. The interval from the day of the first PGF2α treatment to the onset of estrus was 6.5 ± 0.2 days. These results indicate that multiple EDP treatments are required for induction of pseudopregnancy in MMpigs and estrus exhibition can be controlled in MMpigs by treatment with EDP and PGF2α. PMID:27151362

Relationships between the conception rate of estrus synchronization using estradiol benzoate and CIDR (progesterone) and other parameters in holstein lactating dairy cows.

PubMed

Miura, Hiroshi; Kotani, Satoko; Kohiruimaki, Masayuki; Ohtsuka, Hiromichi; Kikuchi, Motohiro; Ohnami, Yoji

2008-06-01

The purpose of this study was to determine the relationships between conception rate and other parameters before estrus synchronization with a Controlled Internal Drug Release Device (CIDR) and estradiol benzoate (EB). In the estrus synchronization program, animals were injected with 2 mg EB and then received a CIDR. Seven days later, the CIDR was removed and the animals were given an injection of Prostaglandin F(2alpha). Twenty-four hours later, they received an injection of 1 mg EB, and they were artificially inseminated 24 h after that. This program was applied to 258 Holstein cows in Tohoku-machi (Aomori, Japan). Blood was collected at the beginning of the program, and the conception rate was determined about 40 days after insemination. The relationships among conception rate, blood biochemical values, age, body condition score and days in milk were statistically analyzed to determine better conditions for cow conception. The conception rate of the cows in the high progesterone group (more than 1 ng/ml, P(4)+) was significantly higher than that of the low progesterone group (less than 1 ng/ml, P(4)-; 47.9% vs. 28.6% P<0.01). In the P(4)- groups, the serum phospholipid level was significantly higher in the conception group than in the non-conception group, and the same tendency was seen in the P(4)+ groups. Blood urea nitrogen (BUN), albumin (Alb), and total cholesterol (TChol) were significantly higher in the conception group compared with the non-conception group, but no with P(4) was observed. We concluded that 1) the conception rate of the P(4)- group was remarkably low, that 2) the low conception rate and low P(4) level was related to a low PL level and that 3) BUN, Alb and TChol were higher in the conception group, although no relation with P(4) was found.

Use of a domestic Korean black goat (Capra hircus coreanae) with its chest crayon-harnessed in detecting estrus of Himalayan tahrs (Hemitragus jemlahicus)

PubMed Central

Yong, Hwanyul

2014-01-01

The reliability of a Korean black goat (Capra hircus coreanae) to detect estrus in Himalayan tahrs (Hemitragus jemlahicus) for an artificial breeding program was investigated. Estrus in six female Himalayan tahrs was synchronized using fluorogestone acetate (FGA) sponges. Thirteen days later, 200 IU of PMSG and 100 IU of hCG were injected before removing the sponges and simultaneously injecting 5 mg of PGF2α the next day. Penetration of the cervical canal and the thickness and location of red crayon marks were examined 40~43 h later. Two females treated with sponges containing 60 or 45 mg of FGA had estrogen levels of 8.7 and 11.1 pg/mL, respectively. No red marks were found on the backs of these two tahrs. The remaining females had higher levels of estradiol, and the red crayon marks were clearly shown. The cervical folds of these tahrs were readily penetrated and the insemination gun was smoothly inserted into the uterine body. In conclusion, a Korean domestic goat with its chest crayon-harnessed was successfully used to detect estrus of Himalayan tahrs. This technique might be utilized as a part of breeding programs for wild goats and avoid the need for a vasectomy of conspecific males. PMID:24690603

Synchronized ovulation for first insemination improves reproductive performance and reduces cost per pregnancy in dairy heifers.

PubMed

Silva, T V; Lima, F S; Thatcher, W W; Santos, J E P

2015-11-01

The objectives were to evaluate the effects of synchronizing estrus and ovulation to implement a timed artificial insemination (AI) at first insemination on reproductive performance and cost per pregnancy in dairy heifers. Six hundred eleven Holsteins heifers at approximately 400 d of age from 3 farms were enrolled in the study. Six days before moving to the breeding pens, heifers were allocated randomly to AI after detected estrus from study d 0 to 84 (CON, n=306), or to timed AI for first AI followed by detected estrus for the remainder of the 84-d study (TAI, n=305). Heifers receiving TAI were enrolled in the 5-d timed AI protocol on study d -6 (d -6, GnRH and a progesterone insert; d -1, PGF2α and insert removal; d 0, PGF2α; d 2, GnRH + AI), and they were allowed to be bred the day before scheduled timed AI if detected in estrus. Starting on study d 0, estrus was detected daily. Heifers in estrus were inseminated on the same morning as detected estrus. Control heifers not inseminated by study d 7 received PGF2α and this treatment was repeated every 2 wk until AI. The study lasted 84 d to allow a period of breeding equivalent to four 21-d estrous cycles. A herd budget accounting for inputs for both treatments was created to determine the cost per pregnancy. Sensitivity analysis compared economic differences between the 2 treatments under different input scenarios when detection of estrus after the first AI varied from 50 to 80%. Interval to first AI was 8 d shorter for TAI than for CON. Pregnancy at first AI did not differ between treatments (CON=58.3 vs. TAI=62.8%). In contrast, TAI increased pregnancy per AI (P/AI) compared with CON in heifers inseminated with sex-sorted semen (CON=31.6 vs. TAI=54.8%). The 21-d cycle insemination rate was greater for TAI (91.4%) than for CON (82.4%), even when evaluated after the first 21 d in the study (CON=68.2 vs. TAI=77.1%). The increased insemination rate improved the 21-d cycle pregnancy rate from 47.9% in CON to 57.2% in TAI heifers. In fact, the hazard of pregnancy was 60% greater for TAI than CON. The increased pregnancy rate in TAI reduced the median days to pregnancy by 12 d (CON=2.0 vs. TAI=14.0) and increased the proportion of pregnant heifers by 6.3 percentage points by study d 84 (CON=85.2 vs. TAI=91.5%). The cost per pregnancy was $17.00 less for TAI than CON. The sensitivity analysis indicated that TAI was economically more advantageous to produce a pregnancy compared with CON. Only when insemination rate after the first 21 d of breeding was very high and P/AI was relatively low did the cost per pregnancy become similar for the 2 treatments. Collectively, inseminating all heifers within 2 d of breeding with the 5-d timed AI protocol maintains P/AI, improves pregnancy rate, and reduces cost per pregnancy compared with insemination after detected estrus. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effects of lipopolysaccharide (LPS) induced inflammatory response on early embryo survival in ewes

USDA-ARS?s Scientific Manuscript database

Early pregnant ewes were used to determine the effects of endogenous (through LPS activation) and exogenous TNF-alpha tumor necrosis factor-alpha (TNF-alpha) on embryonic loss. Thirty-eight Dorset x Texel ewes were synchronized for estrus and bred to fertile rams (d0). On d5/6, ewes were assigned t...

Specialized Veterinary Manpower Needs through 1990,

DTIC Science & Technology

1982-01-01

vaccines and diagnostic tests; and the increased technical sophistication in artificial insemination , embryo culture and transplantation, and hormonal...are included. Artificial insemination , synchronization of estrus, endocrine therapy, spermatozoan and ovum genetic engineering, and ovum and embryo...hospital facility surrounded by satellite clinics that offer restricted medical and surgical services. 26 Qualified animal-health technicians are used to a

Maternal nutrition during the first 50 days of gestation alters bovine fetal hepatic metabolic transcriptome

USDA-ARS?s Scientific Manuscript database

We hypothesized that maternal nutrition during the first 50 d of gestation would alter the metabolic transcriptome of the bovine fetal liver. Fourteen beef heifers were estrus synchronized and assigned to 2 treatments at breeding (CON, 100% of requirements to gain 0.45kg/d; RES, 60% of CON). Heifers...

Maternal nutrition during the first 50 d of gestation alters expression of metal-binding genes in fetal cerebrum

USDA-ARS?s Scientific Manuscript database

We hypothesized that maternal nutrition during the first 50 d of gestation would alter the metal-binding transcriptome of the developing cerebrum. 14 beef heifers were estrus synchronized and assigned to 2 treatments at breeding (CON-100% of requirements; RES-60% of CON). Heifers were ovariohysterec...

Moderate nutrient restriction influences expression of genes impacting production efficiencies of beef cattle in fetal liver, muscle and cerebrum by day 50 of gestation

USDA-ARS?s Scientific Manuscript database

We hypothesized that a moderate maternal nutrient restriction during the first 50 days of gestation in beef heifers would affect expression of genes impacting production efficiency phenotypes in the fetal liver, muscle and cerebrum. Fourteen Angus-cross heifers were estrus synchronized and assigned ...

75 FR 63085 - Certain Other Dosage Form New Animal Drugs; Progesterone Intravaginal Inserts

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-14

... synchronization of estrus in lactating dairy cows. DATES: This rule is effective October 14, 2010. FOR FURTHER... cows. The NADA is approved as of July 22, 2010, and the regulations are amended in 21 CFR 529.1940 to.... * * * * * (d) * * * (2) Cows. This product is approved with the concurrent use of dinoprost solution when used...

The effect of bovine somatotropin (bST) administration on reproduction, progesterone concentration during lactation and LH secretion during estrus, in dairy ewes.

PubMed

Brozos, C N; Saratsis, P; Boscos, C; Kyriakis, S C; Alexopoulos, C

1999-08-16

Twenty-two polytocous lactating Chios ewes were used to test the effects of bovine somatotropin (bST) on reproduction, progesterone concentration and LH secretion during estrus. Half of the ewes were injected every second week with 160 mg bST in a prolonged release vehicle, from the fifth day post partum until the end of lactation, while the remaining ones were used as controls. All animals were fed the same amount of ration. Supplementation with bST resulted in an increase of milk production (P<0.05) and an insignificant trend for delayed resumption of normal estrous cycles. Although there were no differences between groups, there was also a tendency for the bST group to display lower progesterone concentrations during the first three fortnights after the onset of normal estrous cycles and higher ones during the last three fortnights of the experiment, compared with the control group. Duration of the first normal luteal phase after delivery of the bST group was found to be shorter compared with the control group (P<0.05). After estrous synchronization the bST group showed a shorter estrus compared with the control group (P<0.05). Average and baseline LH concentrations during synchronized estrous in the bST group was lower (P<0.001) compared with the control group. Additionally, the conception rate did not differ between the two groups. This study supports the concept that the beneficial effects of bST treatment on milk production outweigh the potential deleterious effects on reproduction.

Potential role for GnRH in the synchronization of follicular emergence before the superovulatory Day 0 protocol.

PubMed

Balaro, M F A; Fonseca, J F; Barbosa, T G B; Souza-Fabjan, J M G; Figueira, L M; Teixeira, T A; Carvalheira, L R; Brandão, F Z

2016-01-01

The ability of gonadotropin-releasing hormone (GnRH) to synchronize ovulation and new follicular wave emergence before a "superovulatory Day 0" protocol was assessed in Santa Inês ewes. For estrus synchronization, a 60-mg medroxyprogesterone acetate sponge was inserted for 6 d. One day before sponge removal, 37.5-μg d-cloprostenol and 300 IU equine chorionic gonadotropin were injected intramuscularly (i.m.). After sponge removal, ewes were assigned to the following 3 groups: (1) GC-1 mL saline at 12 h (n = 10); (2) G24h-0.025-mg lecirelin (GnRH agonist) i.m. at 24 h (n = 10); or (3) G36h-0.025-mg lecirelin i.m. at 36 h (n = 9). Ovarian ultrasonography was conducted to assess follicular dynamics. Blood was collected to determine plasma concentrations of progesterone and estradiol. Females from G36h and GC had a greater (P < 0.05) estrous response than those from the G24h group (78.0 and 90.0 vs 0.0%, respectively). Ewes from G24h and G36h had earlier (P < 0.05) ovulation (48.0 ± 10.2 and 56.7 ± 5.7 h) compared with those from Gc (64.1 ± 9.7 h). The mean number of ovulations per ewe was greater (P < 0.05) in Gc (1.9 ± 0.6) and G36h (2.0 ± 1.0) than G24h (1.2 ± 0.4). Plasma concentrations of progesterone and estradiol differed over time. Follicular growth during the postovulatory day was affected (P < 0.05) by day of the estrus cycle as well as by the interaction (P < 0.05) of treatment and day of the estrus cycle. There was a larger (P < 0.05) population of medium follicles during the first 24 h after the ovulation in G24h compared with Gc, and there was an absence of large follicles in G36h between 36 and 72 h after ovulation. In conclusion, the use of GnRH agonist at 36 h more efficiently synchronized ovulation and promoted the absence of dominant follicles during early diestrus and may be used at the start of superovulatory treatment at 80 h in Santa Inês ewes. Copyright © 2016 Elsevier Inc. All rights reserved.

Moderate nutrient restriction influences transcript abundance of genes impacting production efficiencies of beef cattle in fetal liver, muscle, and cerebrum by d 50 of gestation

USDA-ARS?s Scientific Manuscript database

We hypothesized that a moderate maternal nutrient restriction during the first 50 d of gestation in beef heifers would affect transcript abundance of genes impacting production efficiency phenotypes in fetal liver, muscle, and cerebrum. Fourteen Angus-cross heifers were estrus synchronized and assig...

Strategies to overcome seasonal anestrus in water buffalo.

PubMed

de Carvalho, Nelcio Antonio Tonizza; Soares, Julia Gleyci; Baruselli, Pietro Sampaio

2016-07-01

Reproductive seasonality in buffalo (Bubalus bubalis) is characterized by behavioral, endocrine, and reproductive changes that occur over distinct periods of the year. During the nonbreeding season (spring and summer), the greater light-dark ratio (long days) suppresses estrus behavior and the occurrence of ovulation. Anestrous buffaloes have insufficient pulsatile of LH to support the final stages of follicular development, and subsequently, estrus behavior and ovulation do not occur, limiting reproductive efficiency, especially in artificial insemination (AI) programs. A number of therapeutic strategies designed to synchronize follicular wave emergence and ovulation have allowed for the use of AI throughout the year, overcoming seasonal anestrus in buffalo. These therapies also improve reproductive performance by increasing the service rate and pregnancy per AI in buffalo herds, regardless of reproductive seasonality. Copyright © 2016 Elsevier Inc. All rights reserved.

Video tracking analysis of behavioral patterns during estrus in goats

PubMed Central

ENDO, Natsumi; RAHAYU, Larasati Puji; ARAKAWA, Toshiya; TANAKA, Tomomi

2015-01-01

Here, we report a new method for measuring behavioral patterns during estrus in goats based on video tracking analysis. Data were collected from cycling goats, which were in estrus (n = 8) or not in estrus (n = 8). An observation pen (2.5 m × 2.5 m) was set up in the corner of the female paddock with one side adjacent to a male paddock. The positions and movements of goats were tracked every 0.5 sec for 10 min by using a video tracking software, and the trajectory data were used for the analysis. There were no significant differences in the durations of standing and walking or the total length of movement. However, the number of approaches to a male and the duration of staying near the male were higher in goats in estrus than in goats not in estrus. The proposed evaluation method may be suitable for detailed monitoring of behavioral changes during estrus in goats. PMID:26560676

Concentrations of steroid hormones, estrous, ovarian and reproductive responses in sheep estrous synchronized with different prostaglandin-based protocols.

PubMed

Fierro, S; Viñoles, C; Olivera-Muzante, J

2016-04-01

To determine estrous, ovarian and reproductive responses after different prostaglandin (PG)-based protocols, ewes were assigned to groups PG10, PG12, PG14 or PG16 (twoPG injections administered 10, 12, 14 or 16 days apart; respectively). Experiment I (n=132) was conducted to evaluate the estrous response, ovulation rate (OR), conception and fertility. Experiment II (n=24) was conducted to evaluate ovarian follicle growth, steroid concentrations and the interval from the second PG injection to estrus (PG-estrus) and ovulation (PG-ovulation). Estrous response was less with the PG16 (P<0.05) treatment, and the extent of estrous synchrony was greater with the PG10 and PG12 treatments. Ovarian follicle growth and the intervals for the variables PG-estrus, PG-ovulation and OR were similar among groups (P>0.05). From 8 to 4 days before estrus, progesterone (P4) concentrations were greater for the PG14 and PG16 than for the PG10 and PG12 (P<0.05) groups. There were more days where concentrations of P4 were above 3.18 nmol/L with the PG14 and PG16 than PG10 and PG12 (P<0.05) treatments. Use of the PG14 and PG16 treatments resulted in greater estradiol (E2) at estrus and 12h later than use of the PG10 and PG12 treatments. A positive correlation was observed between the duration of the luteal phase and maximum E2 concentrations, and between duration of the luteal phase and days with E2 concentrations above 10 pmol/L. Conception and fertility were greater with use of the PG14 compared with PG10 and PG12 (P<0.05) treatments. The administration of two PG injections 10, 12, 14 or 16 days apart resulted in different durations of the luteal phase that were positively associated with E2 concentrations and the reproductive outcome. The shorter luteal phases were associated with greater synchrony in time of estrus. The intervals for the variables PG-estrus, PG-ovulation and OR were similar among groups. Copyright © 2016 Elsevier B.V. All rights reserved.

Use of two doses of cloprostenol in different intervals for estrus synchronization in hair sheep under tropical conditions.

PubMed

de Carvalho Menezes de Almeida, Sheylla Foligno; Souza-Fabjan, Joanna Maria Gonçalves; Balaro, Mario Felipe Alvarez; Bragança, Gláucia Mota; Pinto, Pedro Henrique Nicolau; de Almeida, José Gabriel; Moura, Ana Beatriz Bossois; da Fonseca, Jeferson Ferreira; Brandão, Felipe Zandonadi

2018-02-01

This study evaluated the effect of two doses of prostaglandin at different intervals on reproductive parameters of crossbred ewes. In Experiment 1, 30 ewes received two doses of 120 μg cloprostenol at 7 (G 7 days ), 9 (G 9 days ), or 11.5 (G 11.5 days ) days apart. Ultrasound assessments were performed from the first and second cloprostenol administration for 5 days or ovulation detection. Estrus signs were checked by a teaser male. Plasma progesterone concentration was measured before each cloprostenol dose. In Experiment 2, 95 ewes were allocated into the same treatments and after the second dose, ewes in estrus were mated. At 30 days after breeding, pregnancy diagnosis was conducted and prolificacy was evaluated at lambing. In Experiment 1, at the first cloprostenol administration, 50% of ewes had an active CL and all showed estrus. At the second administration, 66.7% of ewes had an active CL and one did not present estrus. There was no difference (P > 0.05) after the second dose for as follows: overall estrous response (90%), interval from cloprostenol administration to estrous onset (42.0 ± 4.9 h), estrus duration (31.5 ± 2.1 h), ovulation rate (100.0%), and number of ovulations (1.5 ± 0.3). In Experiment 2, both pregnancy and prolificacy rates were similar (P > 0.05) for G 7 days (73.3; 145%), G 9 days (75.9; 125%), or G 11.5 days (75.9; 145%), leading to an overall pregnancy rate of 75.0% (66/88) and prolificacy rate of 137% . Therefore, the three treatments proposed were able to promote high pregnancy and prolificacy rates in crossbred ewes.

Starting Ovsynch protocol on day 6 of first postpartum estrous cycle increased fertility in dairy cows by affecting ovarian response during heat stress.

PubMed

Dirandeh, E

2014-10-01

The objective was to compare fertility in cows using an Ovsynch protocol starting on day 6 of first postpartum estrous cycle with an Ovsynch protocol initiated at random stages of the estrous cycle during heat stress (temperature-humidity index (THI)=77-83). Cows (n=459) at the beginning of the lactation period were randomly assigned to time-of-ovulation synchronization treatments: (1) control, Ovsynch (first GnRH treatment, PGF2α treatment 7 days later, second GnRH treatment 56 h later, and TAI 16 h later), initiated at random stages of the estrous cycle (40 ± 2 days postpartum, n=224) and (2) Ovsynch initiated on day 6 of first postpartum estrous cycle (estrus=day 0) based on detection of the first estrus after day 30 postpartum (O6, 35 ± 2 postpartum, n=235). Statistical analyses were conducted using SAS. The percentage of cows responding to the initial GnRH injection using the Ovsynch protocol was greater with the O6 treatment compared to the control treatment (60.4% compared with 52.6%). The percentage of cows having a corpus luteum (CL) on the day of the PGF2α injection was not different among treatments (control=87.0% and O6=90.2%, respectively). Also more cows in the O6 treatment group responded to the second GnRH injection of the Ovsynch protocol compared with control treatments (82.5% compared with 75.8%). Treatment affected the percentage of cows diagnosed pregnant at 32 ± 0.7 days and 60 ± 3 days after the resynchronized timing of AI but pregnancy losses (5.3% compared with 6.8%) did not differ between treatment groups. It is concluded that initiating the Ovsynch protocol 6 days after estrus during the first 40 days postpartum resulted in a greater pregnancy rate at the synchronized estrus and increased fertility compared with control cows during heat stress. Copyright © 2014 Elsevier B.V. All rights reserved.

Estrous synchronization strategies to optimize beef heifer reproductive performance after reproductive tract scoring.

PubMed

Kasimanickam, Ramanathan K; Whittier, William D; Hall, John B; Kastelic, John P

2016-08-01

Three experiments comparing four estrous synchronization protocols were conducted to determine estrous expression rate and artificial insemination pregnancy rate (AI-PR) in heifers with a range (1-5) of reproductive tract scores (RTSs). At enrollment (Day 0), 1783 Angus cross beef heifers from six locations were given body condition score and RTS. The four protocols were: (1) HRTS-DPGF group-heifers with RTS 5 received prostaglandin F2α (PGF; Dinoprost 25 mg; im) on Days 0 and 14; (2) HRTS-CIDR-PGF group-heifers with RTS 5 received a CIDR (1.3-g progesterone) insert on Day 7, followed by CIDR removal and PGF on Day 14; (3) LRTS-CIDR-PGF group-heifers with RTS 4 or less received a CIDR insert on Day 7, followed by CIDR removal and PGF on Day 14; and (4) HRTS-Select-Synch group-heifers with RTS 5 received 100 μg of gonadorelin diacetate tetrahydrate (gonadotropin releasing homone; im) on Day 7 and PGF on Day 14. In all groups, heifers observed in estrus were artificially inseminated (within 120 hours after PGF) using the AM-PM rule. In Experiment 1, estrus expression rates were 82.2% (282/343) and 88.5% (184/208) for HRTS-DPGF and LRTS-CIDR-PGF, respectively (P < 0.05), whereas AI-PR were 51.3% (176/343) and 59.1% (123/208; P < 0.1). In Experiment 2, estrus expression rates were 79.6 (168/211), 86.9 (186/214) and 84.2% (176/209) for HRTS-DPGF, HRTS-CIDR-PGF, and LRTS-CIDR-PGF groups (P > 0.1) and AI-PR were 52.1 (110/211), 60.3 (129/214), and 58.4% (122/209; P > 0.05). In Experiment 3, estrus expression rates were 77.5 (131/169), 85.5 (142/166), and 83.3% (219/263) for HRTS-DPGF, HRTS-Select-Synch and LRTS-CIDR-PGF (P > 0.05) and AI-PR were 53.3 (90/169), 60.2 (100/166), and 58.6% (154/263; P > 0.1). Overall, estrus expression rates for HRTS-DPGF, HRTS-Select-Synch, LRTS-CIDR-PGF, and HRTS-CIDR-PGF groups were 80.4 (581/723), 85.5 (142/166), 85.1 (579/680), and 86.9% (186/214), respectively; higher for heifers in LRTS-CIDR-PGF and HRTS-CIDR-PGF groups compared to heifers in HRTS-DPGF group (P < 0.05). The AI-PR for heifers in HRTS-DPGF was lower (52.0 [376/723]) compared with HRTS-Select-Synch (60.2 [100/166]), LRTS-CIDR-PGF (58.7 [399/680]), and HRTS-CIDR-PGF (60.3 [129/214]); P < 0.05). In conclusion, heifers achieved greater AI-PR after CIDR-PGF or HRTS-Select-Synch estrous synchronization protocols. Even though acceptable AI-PRs achieved in heifers with RTS 5 that were subjected to a double PGF protocol, the reproductive performance was reduced compared with other protocols used in this study. Copyright © 2016 Elsevier Inc. All rights reserved.

Split-time artificial insemination in beef cattle: III. Comparing fixed-time artificial insemination to split-time artificial insemination with delayed administration of GnRH in postpartum cows.

PubMed

Bishop, B E; Thomas, J M; Abel, J M; Poock, S E; Ellersieck, M R; Smith, M F; Patterson, D J

2017-09-01

This experiment was designed to compare pregnancy rates in postpartum beef cows following split-time (STAI) or fixed-time (FTAI) artificial insemination. Estrus was synchronized for 671 cows at seven locations following administration of the 7-d CO-Synch + CIDR protocol (100 μg GnRH + CIDR insert [1.38 g progesterone] on d 0; 25 mg prostaglandin F 2α [PG] at CIDR removal on d 7). Cows were assigned to treatments that were balanced across locations based on age, body condition score, and days postpartum at the time treatments were initiated. All cows in treatment 1 (n = 333; FTAI) were inseminated at 66 h after PG and GnRH was administered concurrent with insemination regardless of estrus expression. For cows in treatment 2 (n = 338; STAI), inseminations were performed at 66 or 90 h after PG, and estrous status was recorded at these times. Cows in the STAI treatment that exhibited estrus by 66 h were inseminated at that time and did not receive GnRH, whereas AI was delayed 24 h until 90 h after PG for cows that failed to exhibit estrus by 66 h. Gonadotropin-releasing hormone (100 μg) was administered concurrent with AI at 90 h only to cows failing to exhibit estrus. Estrus expression that occurred during the 24 h delay period among cows assigned to the STAI treatment increased the total proportion of cows that expressed estrus prior to insemination (1 = 60%; 2 = 86%; P < 0.001). Pregnancy rates for cows inseminated at 66 h that exhibited estrus did not differ between treatments (1 = 58%; 2 = 58%; P = 0.93); however, pregnancy rates among non-estrous cows at 66 h were improved (1 = 35%; 2 = 51%; P = 0.01) among cows assigned to the STAI treatment when insemination was postponed by 24 h. Consequently, total AI pregnancy rate tended to be higher for cows that received STAI (1 = 49%; 2 = 56%; P = 0.06). In summary, following administration of the 7-d CO-Synch + CIDR protocol, total estrous response increased and pregnancy rates resulting from AI tended to be higher among cows assigned to STAI versus FTAI treatments. Copyright © 2017. Published by Elsevier Inc.

Effect of reproductive methods and GnRH administration on long-term protocol in Santa Ines ewes.

PubMed

Biehl, Marcos V; Ferraz Junior, Marcos V C; Ferreira, Evandro M; Polizel, Daniel M; Miszura, Alexandre A; Barroso, José P R; Oliveira, Gabriela B; Bertoloni, Analisa V; Pires, Alexandre V

2017-08-01

This study aimed to determine whether reproductive performance of ewes submitted to laparoscopic timed artificial insemination (TAI) would be similar to ante meridiem (AM)/post meridiem (PM) rule and assisted natural mating (NM), and whether GnRH may enhance the pregnancy rate in TAI. In experiment I, 191 non-lactating ewes were synchronized, then TAI was performed either 48 h after progesterone (P4) removal (TAI-48 h) or 12 h after estrus detection (AM/PM); moreover, some ewes were submitted to NM (NM) as control treatment. In experiment II, 247 non-lactating ewes were allocated in five treatments, a control (no-GnRH on protocol) and four treatments arranged in a factorial design 2 × 2. The factors were time and dose of GnRH: ewes that received either 10 μg (TAI-10 μg-36 h) or 25 μg of GnRH (TAI-25 μg-36 h) 36 h after P4 removal and ewes that received either 10 μg (TAI-10 μg-48 h) or 25 μg of GnRH (TAI-25 μg-48 h) at time of insemination, 48 h after P4 removal. In experiment I, pregnancy rate in TAI-48 h was lower (P = 0.03) than AM/PM and NM. Moreover, the probability of pregnancy in TAI-48 h was higher (P = 0.06) in ewes detected in estrus early. In experiment II, the use of GnRH in TAI protocols increased (P < 0.01) pregnancy rate at synchronization, and TAI-25 μ-48 h and TAI-10 μg-36 h treatments increased (P = 0.02) pregnancy rate compered to TAI-10 μg-48 h. We conclude that TAI decreased pregnancy rate compered to NM and AM/PM, which may be improved by GnRH use in TAI to synchronize ovulation.

Fertility in Angus cross beef cows following 5-day CO-Synch + CIDR or 7-day CO-Synch + CIDR estrus synchronization and timed artificial insemination.

PubMed

Whittier, William D; Currin, John F; Schramm, Holly; Holland, Sarah; Kasimanickam, Ramanathan K

2013-12-01

The present study determined whether a 5-day CO-Synch + controlled internal drug release (CIDR) protocol with two doses of PGF2α would improve timed artificial insemination (AI) pregnancy rate compared with 7-day CO-Synch + CIDR protocol in beef cows. Angus cross beef cows (N = 1817) at 12 locations were randomly assigned to 5-day CO-Synch + CIDR or 7-day CO-Synch + CIDR groups. All cows received 100 μg of GnRH and a CIDR insert on Day 0. Cows (n = 911) in the 5-day CO-Synch + CIDR group received two doses of 25 mg PGF, the first dose given on Day 5 at CIDR removal and the second dose 6 hours later, and 100 μg GnRH on Day 8 and were inseminated concurrently, 72 hours after CIDR removal. Cows (n = 906) in 7-day CO-Synch + CIDR group received 25 mg of PGF at CIDR removal on Day 7, and 100 μg GnRH on Day 10 and were inseminated concurrently, 66 to 72 hours after CIDR removal. All cows were fitted with a heat detector aid at CIDR removal and were observed twice daily until insemination for estrus and heat detector aid status. Accounting for estrus expression at or before AI (P < 0.0001) and body condition score (P < 0.01), cows in the 5-day CO-Synch + CIDR group had greater AI pregnancy rate compared with cows in the 7-day CO-Synch + CIDR group (58.1% vs. 55.1%; P = 0.04). More cows that exhibited estrus at or before AI became pregnant compared with cows that did not [65.7% (681/1037) vs. 44.5% (347/780); P < 0.0001]. The AI pregnancy rate was lesser for cows with body condition ≤4 [≤4 - 49.3% (101/219), 5-6 - 57.9%; >6 - 55.8%]. The mean AI pregnancy rate difference between treatment groups and projected economic outcome varied among locations. In conclusion, cows synchronized with the 5-day CO-Synch + CIDR protocol had greater AI pregnancy rate than those that received the 7-day CO-Synch + CIDR protocol. Copyright © 2013 Elsevier Inc. All rights reserved.

Luteal lifespan and fertility after estrus synchronization in goats

PubMed Central

Chao, Lu Meng; Takayama, Koji; Nakanishi, Yoshitaka; Hamana, Katsumi; Takagi, Mitsuhiro; Kojima, Toshiyuki

2008-01-01

The present experiment aims to examine the efficiency of estrus synchronization using progesterone and equine chorionic gonadotrophin (eCG) and to look at luteal function. During the non-breeding and breeding season, 5 adult female Korean native goats were injected intramuscularly with 2.5 ml of physiological saline as the control. A progesterone impregnated intravaginal sponge was then kept in the same goats for 10 days followed, after a week, by an intramuscular injection of 500 IU eCG. Five adult female Nubian goats were mated with a fertile buck during the non-breeding season. During the non-breeding season 2 of the 5 goats showed a normal estrous cycle (ranging from 18 to 21 days) and 3 a short estrous cycle (ranging from 3 to 6 days). During the breeding season the equivalent figures were 1 and 2. The major axes of the corpus luteum (CL) were measured by means of calipers built into the ultrasonography system, and the concentrations of plasma progesterone (P4) were determined by double antibody radioimmunoassay. The mean major axes of the CL in goats showing the short cycle (6.1 ± 0.5 mm) was significantly smaller than in those showing the normal cycle (8.9 ± 0.5 mm; p < 0.01) and also the value of P4 in goats showing the short cycle (4.2 ± 2.1 ng/ml) was significantly lower than for those showing the normal cycle (10.3 ± 4.3 ng/ml; p < 0.05) at day 3 following ovulation. Three out of 5 Nubian goats became pregnant but only one goat carried to full term. The present experiment indicated that a combination of progesterone and eCG was effective in inducing estrus, although it resulted in a high incidence of short luteal lifespan. The low kidding rate and high incidence of embryonic loss may be due to the instability of the luteal lifespan. PMID:18303279

Cocaine Shifts the Estrus Cycle Out of Phase and Caffeine Restores It

PubMed Central

Malave, Lauren B.

2014-01-01

Background: Sex differences in cocaine abuse are well established. Females have a higher sensitivity and thus higher vulnerability to cocaine abuse compared to males. There are many studies showing that sensitivity to cocaine reward varies during the estrus cycle. Methods: Vaginal smears were examined through a DIFF staining kit and viewed through a microscope to determine the estrus cycle stage. Smears were taken immediately before and after cocaine and/or caffeine injections. Furthermore, we suggest a new tool to analyze the estrus cycle by using electrical resistance of the vaginal mucosa. Results: In the present study, we discovered that cocaine directly induced changes in the estrus cycle. Interestingly, caffeine did not affect the estrus cycle and nor did the combination of cocaine and caffeine. We observed that caffeine blocked the cocaine-induced estrus cycle changes using conventional exfoliate cytology. Therefore, caffeine may have neuroprotective properties on the changes induced by cocaine. Conclusion: These phase changes in the estrus cycle may be the underlying cause of sex differences in cocaine addiction that can be blocked by caffeine. Thus, we propose a valuable insight into sex differences in cocaine abuse and reveal a possible treatment with antagonizing the adenosine system. PMID:25538863

Review: Behavioral signs of estrus and the potential of fully automated systems for detection of estrus in dairy cattle.

PubMed

Reith, S; Hoy, S

2018-02-01

Efficient detection of estrus is a permanent challenge for successful reproductive performance in dairy cattle. In this context, comprehensive knowledge of estrus-related behaviors is fundamental to achieve optimal estrus detection rates. This review was designed to identify the characteristics of behavioral estrus as a necessary basis for developing strategies and technologies to improve the reproductive management on dairy farms. The focus is on secondary symptoms of estrus (mounting, activity, aggressive and agonistic behaviors) which seem more indicative than standing behavior. The consequences of management, housing conditions and cow- and environmental-related factors impacting expression and detection of estrus as well as their relative importance are described in order to increase efficiency and accuracy of estrus detection. As traditional estrus detection via visual observation is time-consuming and ineffective, there has been a considerable advancement of detection aids during the last 10 years. By now, a number of fully automated technologies including pressure sensing systems, activity meters, video cameras, recordings of vocalization as well as measurements of body temperature and milk progesterone concentration are available. These systems differ in many aspects regarding sustainability and efficiency as keys to their adoption for farm use. As being most practical for estrus detection a high priority - according to the current research - is given to the detection based on sensor-supported activity monitoring, especially accelerometer systems. Due to differences in individual intensity and duration of estrus multivariate analysis can support herd managers in determining the onset of estrus. Actually, there is increasing interest in investigating the potential of combining data of activity monitoring and information of several other methods, which may lead to the best results concerning sensitivity and specificity of detection. Future improvements will likely require more multivariate detection by data and systems already existing on farms.

Reproductive Response of Ewes Fed with Taiwan Grass Hay (Pennisetum purpureum Schum.) Supplemented with Duckweed (Lemna sp. and Spirodela sp.)

PubMed Central

Zetina-Córdoba, P.; Ortega-Cerrilla, M. E.; Sánchez Torres-Esqueda, M. T.; Herrera-Haro, J. G.; Ortega-Jiménez, E.; Reta-Mendiola, J. L.; Vilaboa-Arroniz, J.

2012-01-01

The effect of duckweed (DW) supplementation was evaluated on dry matter intake (DMI), presence and duration of estrus, percentage of ewes repeating estrus and pregnancy rate, as well as the concentration of progesterone (P4) in multiparous crossbred ewes from Pelibuey, Dorper, and Katahdin breeds, fed with Taiwan grass hay (TWH). Eighteen ewes with 39.7±4 kg mean body weight, kept in individual pens, were randomly assigned to one of the following treatments: T1: TWH, T2: TWH plus 200 g DW, T3: TWH plus 300 g DW. The ewes were synchronized with 40 mg fluorogestone acetate (FGA) and 400 UI equine chorionic gonadotropin (eCG). Data were analyzed as a completely randomized design using the GLM procedure. DW supplementation had no effect on dry matter intake (p>0.05); however, a slight decrease of TWH intake was observed as DW supplementation increased. No differences (p>0.05) were found in the beginning of estrus, percentage of ewes presenting it, its duration, or pregnancy rate. There were no differences (p>0.05) on P4 concentration among treatments, or treatmentxperiod interaction (p>0.05). However the period was significant (p<0.01), since the P4 levels increased as time increased after the removal of the FGA device and eCG application. PMID:25049670

Induction of estrus during the non-breeding season in Egyptian Baladi goats.

PubMed

Medan, Mohamed; Shalaby, Abdel-Hamid; Sharawy, Sayed; Watanabe, Gen; Taya, Kazuyoshi

2002-01-01

The induction of estrus during the non-breeding season was investigated in 100 Egyptian Baladi goats (Capra hircus). All animals assigned to treatments had low progesterone concentrations (<0.5 ng/ml) tested 2 times 10 days apart to confirm anestrous condition. Animals were assigned to three experimental groups. A group of animals received subcutaneous norgestomet ear implant for 11 days and a single i.m. injection of PGF2alpha 24 hr before implant removal (group I; n=40). Second group of animals received subcutaneous norgestomet ear implant for 11 days and a single i.m. injection of PGF2alpha 24 hr before implant removal and gonadotropin releasing hormone 24 hr after implant removal (group II; n=40). Third group of animals received no treatment (control group; n=20). The percentage of goats that showed estrous behavior during the first 72 hr after implant removal was 77.5, 85.0% and 10.0% in group I, group II and control group, respectively. The fertility rate was 57.5, 70.0% and 10.0% in group I, group II and control group, respectively. In conclusion, estrus can be induced in seasonally anestrous Egyptian Baladi goats using norgestomet and PGF2alpha and the injection of GnRH 24 hr after norgestomet implant removal synchronized ovulation in a higher percentage of goats.

Fertility in Gyr Cows (Bos indicus) with Fixed Time Artificial Insemination and Visual Estrus Detection Using a Classification Table

PubMed Central

Ramírez-Iglesia, Lilido Nelson; Roman Bravo, Rafael María; Díaz de Ramirez, Adelina; Torres, Leandro J.

2014-01-01

The aim of this research was to compare two artificial insemination protocols (AIP): hormonal synchronization with fixed time artificial insemination (SC-FTAI) and the use of a table based on visual observation of estrus signs (VO) in order to identify cows in natural or spontaneous estrus being assigned to AI (NSE-IA). Two groups were formed: in the first group 109 cows were assigned to SC-FTAI, in which a commercial protocol is used; the second one included 108 randomly chosen cows, which were assigned to NSE-AI and in this group a modified table was used. Response variable was first service fertility rate (FSF), which was coded 1 for pregnant and 0 for empty. Predictor variables were AIP, postpartum anestrus, daily milk yield, body condition score at AI and calving number. Statistical analyses included association chi-square tests and logistic regression. Results showed an overall 41.94% FSF and a significant association was detected (P < 0.05) between FSF and daily milk yield; pregnancy rates were 42.20% and 41.67% for the SC-FTAI and NSE-IA groups, respectively (P > 0.05). The odds ratio for the effect of AIP was only 1.050, suggesting no differences in FSF between groups. The NSE-AI protocol can enhance both the technique of VO and reproductive efficiency. Further validation of the table is required. PMID:26464929

Characterization of the management practices of the top milk producing herds in the country.

PubMed

Jordan, E R; Fourdraine, R H

1993-10-01

Out of 128 surveys mailed to dairy farms that had been identified by the nine DHI processing centers as the top milk producing herds in the country, 61 surveys were returned. The predominant forage being fed was corn silage, followed by legume hay and haylage. On average, 6.7 feed additives and 3.5 alternative feeds were fed. Producers reported the following incidences of metabolic disorders: parturient paresis, 7.2%; displaced abomasum, 3.3%; ketosis, 3.7%; and nonspecific downer cow syndrome, 1.1%. Producers scheduled detection of estrus 3.1 times per day. Only 18.3% of the herds used routine synchronization of estrus. Artificial insemination was used on 94.8% of the cows and 88.5% of the heifers. The most important trait in sire selection was PTA for milk. For mastitis control, 75.4% of the producers practiced predipping, 85.2% used individual paper towels, 93.4% practiced postdipping, and 95.1% treated all cows at cessation of milking. Increased profitability and lower costs or higher returns were the primary motivators of these producers. Veterinarians were the most frequent source of information, followed by farm magazines. Satellite delivery of educational programs was the least acceptable delivery method. Extension professionals need to be cognizant of the producers' preferred information sources and delivery systems to ensure accurate, timely, cost-effective transfer of technological advances.

Ovarian and endocrine responses in tropical sheep treated with reduced doses of cloprostenol.

PubMed

Contreras-Solis, Ignacio; Vasquez, B; Diaz, T; Letelier, C; Lopez-Sebastian, A; Gonzalez-Bulnes, A

2009-09-01

The present study aimed to assess the efficacy of reduced doses of cloprostenol for synchronizing estrus and ovulation in hair sheep. With the aim to evaluate the luteolytic activity of reduced cloprostenol doses, a first experiment was performed using a relatively large (group H: 126 microg; n=8), medium (group M: 68.25 microg; n=6) and small (group L: 38.5 microg; n=6) cloprostenol dose. Luteolysis was assessed at Days 3 and 6 after injection (Day 0) by progesterone concentrations (P(4)) and transrectal ultrasonography (US). In Experiment 2, sheep were randomly assigned to the same three doses to evaluate a protocol for estrous synchronization using two injections administered 9 days apart. A third trial was performed with ewes treated (9 days apart) with the large dose (H=126 microg; n=12) and with a small dose adjusted for facilitating volume management (LA=43.75 microg; n=12). Presence of estrous cycling was determined in all the ewes by US and P(4) assay, at Days -9, -6, -2, 0 (Day of second cloprostenol injection), 8 and 11. Bleeding and US were done every 4h from 16 h of the beginning of the estrus during the third trial to assess the preovulatory LH surge and timing of ovulation. Additionally, blood samples were drawn at Days 0, 1, 2 and 3 to assess estradiol (Experiments 2 and 3) and P(4) (Experiment 2) concentrations during the ovarian follicular phase. In all experiments, percentage of animals showing luteolysis, preovulatory follicular dynamics and function and percentage of ewes showing behavioral estrus in response to treatment was similar among groups. Timing of estrus for group H was earlier than group L (28.6+/-1.8h compared with 37.1+/-2.4h; P<0.05). In the third trial, the preovulatory LH peak was higher in the LA group than group H, in terms of maximum mean concentration during the surge (27.7+/-1.8 ng/mL compared with 21.3+/-2.2 ng/mL; P<0.05) and area under the curve (AUC; 183.4+/-12.7 ng/mL compared with 127.7+/-10.9 ng/mL; P<0.01). However, timing of ovulation was similar for H and LA groups. Thereafter, ovulation rate and luteal function at Day 11 were similar. Current results demonstrate that reduced doses of cloprostenol may be applied in a practical manner for reproductive management of sheep, with the additional advantage of reducing treatment costs.

Factors affecting pregnancy rate following nonsurgical embryo transfer in buffalo (Bubalus bubalis): a retrospective study.

PubMed

Misra, A K; Rao, M M; Kasiraj, R; Reddy, N S; Pant, H C

1999-07-01

The objectives of this study were to determine the pregnancy rate and factors affecting it following nonsurgical embryo transfer in buffalo. Donor buffalo were superovulated with FSH, and embryos collected nonsurgically were evaluated for stage of development and quality. They were transferred nonsurgically to 91 recipients on Days 5 to 7 of the natural (n = 52) or induced (n = 39) estrus (estrus = Day 0). The overall pregnancy rate of 24/91(26.4%) was higher than in earlier reports for buffalo but was much lower than in cattle. Pregnancy rates were not affected by season (autumn vs winter), side of transfer (right vs left uterine horn), or type of estrus (spontaneous vs induced). The pregnancy rate was high 11/27(40.7%) when donors and recipients were closely synchronized, while it was compromised when recipients were in estrus at +12 h (1/7, 14.3%) and at -12 h (5/27, 18.5%). Asynchrony beyond 12 h on either side resulted into conception failure. The pregnancy rate tended to increase with the increase in CL size of recipients, while stage of embryonic development had no effect. The transfer of an 8-cell embryo with a 16-cell embryo led to the birth of heterosexual twins, indicating that the uterine milieu of Day 5 to 6 recipients may be tolerated by the out-of-phase 8-cell embryo, at least in the presence of a more mature embryo. Embryo quality had the greatest effect on pregnancy rate as it was higher (P < 0.005) after the transfer of Grade I than Grade III embryos (6/10, 60.0% vs 3/36, 13.9%). Assessment of returns to estrus indicated that among nonpregnant recipients, 17/67 (25.4%) embryos never matured sufficiently to prevent luteolysis through maternal recognition of pregnancy (MRP), while 14/67 (20.8%) embryos probably died following MRP. These results indicate that efforts to increase pregnancy rate following embryo transfer in buffalo should include prevention of luteolysis during the first week of transfer and a reduction in the incidence of embryonic mortality.

The effect of follicle age on pregnancy rate in beef cows.

PubMed

Abreu, F M; Geary, T W; Cruppe, L H; Madsen, C A; Jinks, E M; Pohler, K G; Vasconcelos, J L M; Day, M L

2014-03-01

The effect of the age of the ovulatory follicle on fertility in beef cows was investigated. Multiparous (n = 171) and primiparous (n = 129) postpartum beef cows in 2 groups (G1 and G2) received estradiol benzoate (EB; 1 mg/500 kg BW, intramuscular [i.m.]) 5.5 d (G1; n = 162) and 6.5 d (G2; n = 138) after the final GnRH of a synchronization program (5d CO-Synch + CIDR) to induce emergence of a new follicular wave (NFW), followed by prostaglandin F2α (PGF(2α); 25 mg, i.m.) administration either 5.5 d ("young" follicle, YF; n = 155) or 9.5 d ("mature" follicle, MF; n = 145) after EB. Estrous detection coupled with AI 12 h later (estrus-AI) was performed for 60 h (MF) and 84 h (YF) after PGF(2α); cows not detected in estrus within this period received timed AI (TAI) coupled with GnRH at 72 and 96 h, respectively. Within the first 72 h after PGF(2α), more (P < 0.01) cows in the MF (76.3%) than YF treatment (47.7%) exhibited estrus, but through 96 h, the proportion detected in estrus (P < 0.05) and interval from PGF(2α) to estrus (P < 0.01) were greater in the YF than MF treatment (88.6% vs. 76.3%, 78.9 ± 0.8 vs. 57.5 ± 1.6 h, respectively). Age of the ovulatory follicle at AI was greater (P < 0.01) in the MF (9.32 ± 0.04 d) than YF (6.26 ± 0.02 d) treatment, but follicle diameter at AI and pregnancy rates did not differ between MF (13.1 ± 0.2 mm; 72.0%) and YF (12.9 ± 0.1 mm; 67.1%) treatments. Regardless of treatment, the diameter of the ovulatory follicle at AI and pregnancy rate were greater (P < 0.01) with estrus-AI (13.1 ± 0.1 mm; 75.0%) than TAI (12.6 ± 0.2 mm; 55.4%). Cows in the MF treatment that initiated a second NFW after EB but before PGF(2α) (MF2; n = 47) were induced to ovulate with GnRH and TAI at 72h, when ovulatory follicles were 4 d old and 10.2 ± 0.2 mm in diameter. Pregnancy rate for TAI (51.1%) in MF2 did not differ from TAI pregnancy rate (55.4%) across the MF and YF treatments. In summary, the age of the ovulatory follicle affected interval to estrus and AI but did not influence pregnancy rate in suckled beef cows.

[Fertility after treatment with Eazi-breedTM CIDR G for 6 or 12 days outside the breeding season in Lacaune dairy sheep].

PubMed

Fleisch, A; Piechotta, M; Bollwein, H; Janett, F

2013-07-01

This study compares the fertility after short- and long-term synchronization using a progesterone intravaginal device in Lacaune dairy sheep outside the breeding season. For the experiment 108 Lacaune sheep were treated with Eazi-breed™ CIDR® G intravaginal devices (Pfizer Animal Health, Zürich) for 12 days (Group L, n = 60) or 6 days (Group K, n = 48) in combination with eCG (Group L) or with eCG and 125 μg Cloprostenol (Group K) at device removal. Thereafter the ewes were kept together with rams for 60 days, ewes in estrus were recorded and the fertility was assessed after lambing. Blood progesterone concentration was measured at device application, withdrawal and 14 days later. Results show that neither treatment nor parity had an influence on estrus rate (Group L 91.7 %, Group K 93.8 %, nulli- and pluriparous animals 96.9 % and 90.8 %, respectively). Group L showed a tendency towards a better first cycle lambing rate and a significantly (P < 0.05) higher overall lambing rate compared to sheep of Group K (71.7 % vs. 60.4 % and 83.3 % vs. 72.9 %). Pluriparous ewes had higher (P < 0.05) lambing rates and greater (P < 0.05) numbers of lambs born per synchronized ewe than nulliparous sheep for the first cycle (75.0 % vs. 46.9 % and 1.4 ± 1.0 vs. 0.9 ± 1.1) as well as for the overall service period (92.1 % vs. 46.9 % and 1.7 ± 0.8 vs. 0.9 ± 1.1). Fourteen days after insert withdrawal progesterone concentrations were higher (P < 0.05) in Group L than in Group K (7.7 ± 4.3 vs. 5.6 ± 2.7 ng/mL) and in nulli- compared to pluriparous (9.1 ± 5.6 vs. 5.7 ± 2.1 ng/mL) ewes. In conclusion, the overall lambing rate was higher after long-term compared to short progesterone treatment and nulliparous ewes were less suitable for estrus induction outside the breeding season.

The effect of administering a dopamine agonist (Cabergoline) on follicular and luteal development during pro-estrus and estrus in the female greyhound.

PubMed

De Rensis, F; Spattini, G; Ballabio, R; Scaramuzzi, R J

2006-09-01

To study the effect of the dopamine agonist Cabergoline, on ovarian activity in the female dog during pro-estrus and estrus, 6 greyhounds were treated with 5 microg/kg per os of Cabergoline for 20 days beginning on the first day of pro-estrus; 6 animals were left untreated (controls). Ovarian morphology was determined by ultrasound examination once a day during pro-estrus and twice a day during estrus. Follicles were divided into three classes on the basis of their diameter: F1 (<3mm), F2 (3-6mm) and F3 (>6mm). The presence and diameters of post-ovulatory follicles (F-POST) and corpora lutea (CL) were also recorded. Blood samples were taken once a day during pro-estrus and twice a day during estrus. The plasma was assayed for LH, prolactin and progesterone by radioimmunoassay. There were no differences between Cabergoline-treated and control dogs in the duration of pro-estrus or estrus. There was a progressive increase in follicle diameter from the start of pro-estrus when follicles were mainly class F1 to the day of estrus when follicles were mainly class F3. Three days after the start of estrus, the first F-POST follicles were detected. This pattern of development continued and on day 5 the first CLs were detected. By day 9, only CLs were detected. The peak of pre-ovulatory LH was within 3 days of estrus and ovulation was detected in all animals within 3 days of the LH peak. There were no differences in LH concentrations between groups. Plasma prolactin levels varied between animals and were reduced in treated dogs, however, this was not statistically significant (P=0.12). Plasma progesterone levels were below 1.0 ng/ml before the LH surge and thereafter gradually increased. There were no differences in plasma progesterone concentrations between treated and control dogs. In conclusion these results show that the administration of the dopamine agonist Cabergoline during pro-estrus and estrus did not affect the duration of pro-estrus or estrus or the pattern of follicular and luteal development in female dogs.

Effect of monensin and progesterone priming on ram-induced reproductive performance of boutsiko mountain breed ewes.

PubMed

Peclaris, G M; Koutsotolis, K; Seferiadis, K; Mantzios, A; Nikolaou, E; Kolios, G

1999-02-01

The effects of monensin and progesterone priming on reproductive performance (estrous response, lambing rate and prolificacy) of grazing Boutsiko mountain breed adult and 18-mo.-old ewes at the end of seasonal anestrus were investigated. In Experiment 1 the feed supplement with or without monensin was offered for 21 d after introduction of vasectomized rams (Day 0). Progesterone was administered to the ewes in the respective groups as a single injection at Day -3. Ewes of both age groups were assigned randomly to 1 of 4 treatments: C, C+P, C+M and C+M+P. In Experiment 2 the supplement C or M was offered from Day -26 to Day 21. The treatments consisted of C, C+P and C+M+P. Blood samples were taken 50 h after ram introduction for determination of plasma concentrations of P and insulin-like growth factor-I (IGF-I). There was a greater increase in estrous response at Days 17 to 19 and at Days 0 to 19 when supplementation was offered before rather than after ram introduction in both age groups. In the adult group ewes synchronization of estrus at Days 17 to 19 was significantly increased by administration of monensin (P<0.05) and progesterone (P<0.01) compared with the control group in the first but not the second experiment. The incidence of estrus at Days 17 to 19 or at Days 0 to 19 was highest in the adult groups treated with monensin and progesterone in both experiments. In 18-mo.-old ewes progesterone was effective in synchronizing estrus only in Experiment 2. Mean plasma IGF-I concentrations were increased by monensin treatment (P<0.05) in adult ewes that were at the periovulatory stage at blood sampling time. Correlation coefficients between IGF-I and progesterone concentrations in monensin plus progesterone group adults were -0.715 (P<0.02) and -0.516 (P<0.01), respectively across all treatments. The results suggest that monensin and progesterone priming improved reproductive performance, and the monensin-induced increase in plasma IGF-I levels at the periovulatory stage may be causally related to the ability of ovulatory follicles to develop into functional corpora lutea (CL).

Use of pulsatile intravenous administration of gonadotropin-releasing hormone to induce fertile estrus in bitches.

PubMed

Cain, J L; Cain, G R; Feldman, E C; Lasley, B L; Stabenfeldt, G H

1988-11-01

The pulsatile IV administration of gonadotropin-releasing hormone (GnRH) was evaluated as a method to induce fertile estrus in 8 anestrous Beagle bitches. Bitches received 1.25 micrograms of GnRH every 90 minutes for 11 to 13 days. Gonadotropin-releasing hormone was delivered by use of an automatic pump. Reproductive history was known for all bitches, 4 of which, on the basis of 3 or 4 preceding cycles, had an interestrous interval of 219 +/- 14 days (mean +/- SEM). Estrus induction was attempted during early anestrus in 6 bitches (ie, 148 +/- 10 days since the preceding estrus) and late anestrus in 1 bitch (ie, 260 days since the preceding estrus); another bitch had not had an estrous cycle for nearly 2 years before GnRH administration. Signs of estrus were seen within 16 days after the start of GnRH administration in the bitches with regular estrous cycles (group 1, n = 7), and within 23 days in the bitch (group 2) with prolonged anestrus. All bitches were bred, and 7 of 8 (87.5%) became pregnant, with a mean litter size of 4.5 +/- 0.75. A normal hormonal response pattern was observed in group-1 bitches--a peak increase in plasma estrogen concentration of 22.3 +/- 2 pg/ml immediately before the onset of estrus. Peak plasma progesterone concentration (17.3 +/- 3 ng/ml) was observed 1 to 14 days after the onset of diestrus in the group-1 bitches that ovulated, and adequate plasma progesterone concentration was maintained throughout gestation.(ABSTRACT TRUNCATED AT 250 WORDS)

Improvement of bovine in vitro embryo production by ovarian follicular wave synchronization prior to ovum pick-up.

PubMed

Cavalieri, F L B; Morotti, F; Seneda, M M; Colombo, A H B; Andreazzi, M A; Emanuelli, I P; Rigolon, L P

2018-09-01

This study evaluated the effects of the synchronization of ovarian follicular wave emergence on the efficiency of in vitro embryo production. Bos indicus cows (n = 20) were divided into two groups (control vs. synchronization) and subjected to repeated ovum pick-up (OPU) sessions (8 replicates each, with an interval of 21 days in a 2 × 2 crossover design) and subsequent in vitro embryo production. Cows in the control group (n = 10) were submitted to OPU procedures without any stimulation every 21 days. Animals in the synchronization group received a protocol-based progesterone implant, estradiol benzoate and prostaglandin on a random day of the estrus cycle (Day 0) and the OPU was performed on Day 5. After in vitro production, embryos were transferred to recipients synchronized at a fixed time and the diagnosis was performed 60 days later. An evaluation of the parameters for each OPU session revealed that donors that received the synchronization protocol pre-OPU showed a greater number of embryos (5.9 ± 0.5 vs. 4.5 ± 0.4; P = 0.037), higher rate of embryo production (45.8% vs. 38.5%; P = 0.001) and higher mean number of conceptions per group (2.2 ± 0.2 vs. 1.6 ± 0.2; P = 0.07) in relation to the group that did not receive hormonal treatment. We concluded that synchronization of the follicular wave prior to OPU showed positive effects on in vitro embryo production as well as on pregnancy rates. Copyright © 2017 Elsevier Inc. All rights reserved.

Fertilization and embryo recovery rates in superovulated chios ewes after laparoscopic intrauterine insemination.

PubMed

Lymberopoulos, A G; Amiridis, G S; Kühholzer, B; Besenfelder, U; Christodoulou, V; Vainas, E; Brem, G

2001-06-01

Forty superovulated dairy ewes of the Greek Chios breed were used in an experiment to evaluate the efficiency of laparoscopic intrauterine insemination on fertilization and embryo recovery rates as well as embryo quality. Estrus was synchronized by intravaginal progestagen impregnated sponges and superovulation was induced by administration of 8.8 mg o-FSH i.m. following a standard 8 dose protocol. A small volume (0.3 mL) of diluted fresh ram semen was deposited in each uterine horn 24 to 28 h after onset of the estrus by a laparoscopic technique. The animals were allocated randomly into two groups (Group A and B) of 20 animals each. In Group A, embryos were recovered 18 to 24 h after the intrauterine insemination and in Group B on Day 6. The average number of corpora lutea was 12.8 +/- 1.2 and 11.5 +/- 1.1 (+/- SEM); the overall embryo recovery was 66.4% and 57% and the percentage of recovered fertilized ova was 81% and 82.8% in Groups A and B, respectively. More fertilized ova were collected per ewe from Group A (P < or = 0.1). Results indicated that in Chios breed, superovulation using homologous FSH combined with laparoscopic AI leads to good ovarian response with satisfactory results in fertilization, embryo recovery and quality of embryos. This could lead to improved and more efficient methods for obtaining large numbers of high quality oocytes and embryos for embryo transfer programs which could contribute to genetic improvement and increase of the population size.

Expression of receptors for ovarian steroids and prostaglandin E2 in the endometrium and myometrium of mares during estrus, diestrus and early pregnancy.

PubMed

Silva, E S M; Scoggin, K E; Canisso, I F; Troedsson, M H T; Squires, E L; Ball, B A

2014-12-30

The objective of this study was to compare expression of estrogen receptor alpha (ER-α), β (ER-β), progesterone receptor (PR), as well as prostaglandin E2 type 2 (EP2) and 4 (EP4) receptors in the equine myometrium and endometrium during estrus, diestrus and early pregnancy. Tissues were collected during estrus, diestrus, and early pregnancy. Transcripts for ER-α (ESR1), ER-β (ESR2), PR (PGR), EP2 (PTGER2) and EP4 (PTGER4) were quantified by qPCR. Immunohistochemistry was used to localize ER-α, ER-β, PR, EP2 and EP4. Differences in transcript in endometrium and myometrium were compared by the ΔΔCT method. Expression for ESR1 (P<0.05) tended to be higher during estrus than diestrus in the endometrium (P=0.1) and myometrium (P=0.06). In addition, ESR1 expression was greater during estrus than pregnancy (P<0.05) in the endometrium and tended to be higher in estrus compared to pregnancy in the myometrium (P=0.1). Expression for PGR was greater (P<0.05) in the endometrium during estrus and diestrus than during pregnancy. In the myometrium, PGR expression was greater in estrus than pregnancy (P=0.05) and tended to be higher during diestrus in relation to pregnancy (P=0.07). There were no differences among reproductive stages in ESR2, PTGER2 and PTGER4 mRNA expression (P>0.05). Immunolabeling in the endometrium appeared to be more intense for ER-α during estrus than diestrus and pregnancy. In addition, immunostaining for PR during pregnancy appeared to be more intense in the stroma and less intense in glands and epithelium compared to estrus and diestrus. EP2 immunoreactivity appeared to be more intense during early pregnancy in both endometrium and myometrium, whereas weak immunolabeling for EP4 was noted across reproductive stages. This study demonstrates differential regulation of estrogen receptor (ER) and PR in the myometrium and endometrium during the reproductive cycle and pregnancy as well as abundant protein expression of EP2 in the endometrium and myometrium during early pregnancy in mares. Copyright © 2014 Elsevier B.V. All rights reserved.

Ideal proportion of roughage and concentrate for Malpura ewes to adapt and reproduce in a semi-arid tropical environment.

PubMed

Indu, Shekhawat; Sejian, Veerasamy; Kumar, Davendra; Pareek, Arvind; Naqvi, Syed Mohammad Krusheed

2015-12-01

The study was designed to identify the most appropriate roughage to concentrate ratio for Malpura ewes under semi-arid tropical environments. The study was conducted for a period of 35 days and included 30 (2 years old) non-pregnant Malpura ewes weighing between 30 and 35 kg. Estrus synchronization was carried out in all the animals using indigenously developed intravaginal sponges impregnated with progesterone. The ewes were randomly divided into three groups (n = 10/group) namely R50 (n = 10; roughage to concentrate, 50:50), R60 (n = 10; roughage to concentrate, 60:40), and R70 (n = 10; roughage to concentrate, 70:30). Individual feed and water intake was recorded on a daily basis throughout the course of the study. Growth variables, physiological responses, blood metabolites, and endocrine responses were estimated at weekly intervals. Results of the study indicated that nutritional treatment significantly influenced growth variables including body weight (p < 0.01), BCS (p < 0.01), feed intake (p < 0.05), and water intake (p < 0.01) among the different treatment groups. The highest growth variables were recorded in R50 whereas the lowest were in R70. Both respiration rate (p < 0.01) and plasma estradiol levels (p < 0.05) also showed a similar trend as that of the growth variables. However, growth hormone (p < 0.01), T3 (p < 0.01), Hb (p < 0.01), glucose (p < 0.05), and estrus duration (p < 0.05) demonstrated a reverse trend with highest values recorded in R70 and lowest in R50. However, the nutritional treatment did not influence pulse rate, rectal temperature, T4, progesterone, PCV, total cholesterol, total protein, albumin, estrus%, and estrus cycle length. Since the additional concentrate supplementation in R50 and R60 did not improve the production variables, it can be concluded that providing 70 % roughage and 30 % concentrate could be a more appropriate and economically feasible ration composition for Malpura ewes reared in semi-arid tropical environments.

Do high progesterone concentrations decrease pregnancy rates in embryo recipients synchronized with PGF2alpha and eCG?

PubMed

Nogueira, Marcelo F Gouveia; Melo, Danilas S; Carvalho, Luciano M; Fuck, Egon J; Trinca, Luzia A; Barros, Ciro Moraes

2004-05-01

The objective of this study was to evaluate the effects of equine chorionic gonadotropin (eCG) treatment on the number of induced accessory corpora lutea (CL), plasma progesterone concentrations and pregnancy rate in cross-bred heifers after transfer of frozen-thawed (1.5M ethylene glycol) embryos. All recipients received 500 microg PGF2alpha (dl-cloprostenol, i.m.) at random stages of the estrous cycle (Day 0) and were observed for estrus for 7 days. On Day 14, heifers detected in estrus between 2 and 7 days after PGF2alpha treatment were randomly allocated to four groups ( n=83 per group) and given 0 (control), 200, 400, or 600 IU of eCG. Two days later (Day 16), these recipients were given PGF2alpha and observed for estrus. Six to eight days after detection of estrus, plasma samples were collected to determine progesterone concentration and ultrasonography was performed to observe ovarian structures. Heifers with multiple CL or a single CL >15 mm in diameter received an embryo by direct transfer. Embryos of excellent and good quality were thawed and transferred to the recipients by the same veterinarian. Pregnancy was diagnosed by ultrasonography and confirmed by transrectal palpation 21 and 83 days after embryo transfer (ET), respectively. Plasma progesterone concentrations on the day of transfer (Day 7 of the estrous cycle) were 3.9+/-0.7, 4.2+/-0.4,6.0+/-0.4 and 7.8+/-0.6 ng/ml for groups Control, 200, 400, and 600, respectively (Control versus treated groups P=0.009; 200 versus 400 and 600 groups P=0.0001; and 400 versus 600 P=0.012 ). Conception rates 83 days after ET were 41.9, 50.0, 25.0, and 20.9% for groups Control, 200, 400, and 600, respectively (200 versus 400 and 600 groups P=0.0036 ). In conclusion, an increase in progesterone concentration, induced by eCG treatment, did not improve pregnancy rates in ET recipients. Conversely, there was a decline in conception rates in the animals with the highest plasma progesterone concentrations.

Effects of Ficus asperifolia on normal rat estrus cyclicity

PubMed Central

Ngadjui, Esther; Watcho, Pierre; Nguelefack, Telesphore Benoit; Kamanyi, Albert

2013-01-01

Objective To evaluate Ficus asperifolia (Moraceae) (F. asperifolia) effecting on regular estrus cycle of Wistar rats. Methods Air-dried fruits of F. asperifolia were extracted using water. Prior to the test, vaginal smear was monitored daily for a 3-week period to select females with normal (regular) estrous cycle. Those with regular estrus cycle weighing between 150–170 g were randomized into three sets of 15 animals each. Each set was then divided into three groups: Group 1 (control) was orally administered with distilled water (10 mL/kg body weight) once a day for 1 week starting from the proestrus stage. Groups 2 and 3 were respectively treated with 100 and 500 mg/kg body weight of the plant aqueous extract. The two other sets of 15 animals each were similarly treated as the first set for 3 weeks and 6 weeks respectively. Estrus cycle pattern was monitored before and during plant extract application whereas lipid profile, ovary, uterus and liver growth indices were determined at the end of each treatment. Results F. asperifolia did not disrupt (0%) the order of appearance of normal estrus cycle stages, namely, proestrus, estrus, metestrus and diestrus. Short-term treatment (1 week duration) exhibited high frequency of appearance of proestrus and estrus stages while mid- (3 weeks) and long-term (6 weeks) treatments revealed constancy in the frequency of all stages irrespective to animal groups. The plasma and organ lipid profile, as well as ovary, uterus and liver growth remained unchanged when compared to distilled water-treated animals. Following long-term administration of plant extract (6 weeks), no adverse effect was noticed. Conclusions Our data partially support the use of F. asperifolia in common medicine. PMID:23570017

Progesterone concentration as an indicator of ovarian response to superovulation in Chios ewes.

PubMed

Amiridis, G S; Rekkas, C A; Fthenakis, G C; Vainas, E; Lymberopoulos, A; Christodoulou, V; Belibasaki, S

2002-02-01

We investigated the prediction of the ovarian response to superovulation using progesterone (P4) determination in Chios ewes. During the estrus period. estrus synchronization and multiple ovulations were induced in 100 non-pregnant, non-lactating Chios ewes by a combination of FGA-impregnated intravaginal sponges and 8.8 mg of ovine FSH. Laparoscopic insemination was conducted 24-28 h after the onset of estrus. A concentration of P4 was determined on Day 5 of the estrous cycle and on Day 6 the ovarian response was evaluated by counting the corpus lutea (CL); subsequently, embryo collection was performed. According to the response of their ovaries, ewes were allocated into four groups: A (n = 30); B (n = 37); C (n = 22); D (n = 11), with minimal (0-3 CL), moderate (4-8 CL), good (9-13 CL) or extreme (> 13 CL) ovarian response, respectively. In groups C and D, the mean blood serum P4 concentration (23.2 and 27.3 ng/ml, respectively) was higher (P < 0.001) than that in groups A and B (4.6 and 13.1 ng/ml, respectively); no difference was detected in blood P4 concentration between groups C and D. A strong linear relation (F < 0.00005) was found between blood P4 concentration and the number of CL, as well as between blood P4 and a dummy variable corresponding to poor (< 4 CL) or moderate/good/extreme ovarian response (>3 CL). Our results indicate that based on blood P4 measurement, it is feasible to identify ewes that should show the highest embryo recovery, while it is impossible to predict the exact number of CL formed.

Flehmen response in bull: role of vaginal mucus and other body fluids of bovine with special reference to estrus.

PubMed

Sankar, R; Archunan, G

2004-07-30

The present investigation was carried out with a view to evaluate the frequency of Flehmen behaviour in bull in response to body fluids of cows in various stages of the estrous cycle, in the context of estrus detection. The study was performed on free moving bulls under natural conditions. Samples of vaginal mucus, saliva, faeces and milk of pro-estrus, estrus and di-estrus stages collected from donor cows were rubbed individually onto the genital regions of non-estrus animals (dummy cows) and the bulls were observed for 30 min for assessment of Flehmen behaviour. The duration of Flehmen behaviour shown by bulls was maximum towards the dummy cows receiving estrus sample. Such Flehmen behaviour, however, did not occur in bulls in response to the cows receiving samples of other stages. The statistical significance was higher (P < 0.001) in exhibiting repeated Flehmen behaviour towards estrus as compared to those of pro-estrus and di-estrus. Among the various body fluids tested, the exhibition of Flehmen behaviour was significantly higher (P < 0.01) in response to estrus vaginal fluid. No response was observed on dummy cows (control) to which only water was applied on the genital region. The results suggest that vaginal mucus may act as an additional/secondary source along with urine in eliciting copulatary behaviour and executing coitus in bulls during estrus. The results further suggest that in addition to vaginal mucus, other body fluids like saliva, faeces and milk have estrus-related odours and are probably involved in bovine bio-communication.

JSAR Innovative Technology Award. Development of ovulation synchronization and fixed time artificial insemination in dairy cows.

PubMed

Yamada, Kyoji

2005-04-01

Recently, reproductive management has become more difficult as a result of increased herd size. Problems with missing estrous signs and decrease in conception rate by artificial insemination (AI) performed at wrong timing have caused low AI conception rates. In 1995, ovulation synchronization and fixed-time AI (Ovsynch/TAI) was developed in the USA as a new reproductive technology, which was accepted as an useful reproductive management tool in many countries. However, no information on the use of Ovsynch/TAI was available in Japan. It was, therefore, warranted to show the ovulation rate and conception rate after Ovsynch/TAI using gonadotropin releasing hormone analogue (GnRH-A, fertirelin acetate) and prostaglandin F2alpha (PGF2alpha)-THAM, both were commercially available in this country. The conception rate after Ovsynch/TAI has been known to vary among different herds and individuals. Investigation and analysis of factors affecting the conception rate was also warranted to improve the conception rate. A series of experiments were carried out to establish Ovsynch/TAI using domestically produced GnRH-A and PGF2alpha and to study factors affecting conception rate after Ovsynch protocol. Ovsynch using 100 microg GnRH-A and 25 mg PGF2alpha were observed using ultrasonography. As a result, a high synchronization rate of ovulation at 16 to 20 h after the second GnRH injection was confirmed. The conception rate after Ovsynch/TAI was compared in 87 cows with the conception rate after AI at estrus induced by PGF2alpha (139 cows). Conception rate after Ovsynch/TAI was higher than the figure after AI at induced estrus (59.1% vs 20.9%, P<0.05). The dose of GnRH-A was also studied and a practical dose of GnRH-A was found to be 50 microg per cow. To clarify some factors affecting the conception rate after Ovsynch/TAI, 1,558 cows were investigated for the state of their ovaries, days after calving, parity, season, ovarian cyclicity postpartum and nutritional state at the day of Ovsynch. The overall conception rate after Ovsynch/TAI was 51.5%. Fifty-six cows (3.6%) showed estrus at 6 to 7 d after the first injection of GnRH-A. The conception rate after Ovsynch/TAI was low in cows that were 40 to 60 d postpartum, those in their 5th lactation or more, those bred in July to August, and those recovering ovarian cyclicity later than 56 d postpartum. The conception rate after Ovsynch/TAI was high in cows in which body condition score (BCS) was 3.75 at dry period and 3.0 at the day of Ovsynch. In conclusion, Ovsynch/TAI is an effective tool for the reproductive management of dairy cows. A steady and sufficient conception rate after Ovsynch/TAI could be expected by taking the factors affecting the conception rate into the consideration.

When is a cow in estrus? Clinical and practical aspects.

PubMed

Roelofs, J; López-Gatius, F; Hunter, R H F; van Eerdenburg, F J C M; Hanzen, Ch

2010-08-01

Good detection of estrus is critically important in dairy husbandry. Incorrect detection of estrus is related to loss of profit due to extended calving intervals, milk loss, veterinary costs, etc. Detection of estrus remains a major problem despites enormous progress in the knowledge of reproductive physiology of the cow and in development of estrus detection aids. To achieve good estrus detection, many factors have to be taken into account. On one hand a cow has to express estrus and on the other hand the farmer has to detect it. Combined action of several hormones causes physiological changes that lead to ovulation and an environment in the uterus that allows sperm to fertilize the egg. Besides these internal actions, a number of external changes can be observed. When using visual observations, time of the day and time spend on observation have a great impact on detection rates. Many devices are available to aid in estrus detection, such as pedometers, mount devices, temperature, and hormone measurements. Expression of estrus can be influenced by many factors. Heritability, number of days postpartum, lactation number, milk production, and health are known to influence estrus expression. Environmental factors like nutrition, season, housing, herd size, etc. also play a role in estrus expression. To evaluate estrus detection, record keeping is very important; a number of formulas can be used to assess detection efficiency. Besides the farmer, the veterinarian and inseminator can play an important role in estrus confirmation and good insemination strategy. In the end, the time of ovulation and the age of the egg at sperm penetration is critical for conception. Therefore, emphasis in research needs to be on the timing of insemination relative to ovulation, and thus on the detection of ovulation. Copyright 2010 Elsevier Inc. All rights reserved.

Relationship between daily rumination time and estrus of dairy cows.

PubMed

Reith, S; Hoy, S

2012-11-01

The aim of the study was to investigate whether rumination time (RT) was related to estrus in dairy cattle. On 4 farms, cows were equipped with a microphone-based sensor system that allowed continuous recording (in blocks of 2 h) of RT. The analyzed data set consisted of 265 verified estrus cycles of 224 animals with artificial insemination leading to conception. The day of estrus (d 0) was defined as the day when estrus was identified either by measurement of physical activity or by visual observation. In estrous cows, RT was significantly reduced. With a duration of 355 min/d, the minimum RT was found on the day of estrus compared with the base level of 429 min/d during the reference period (the mean of 3 d before and 3 d after estrus). The average decrease in RT was 17% (74 min), ranging between -71 and +16% among animals. Herd and parity affected the RT decrease during estrus. Among the 4 analyzed herds, the RT decrease of cows in estrus ranged between 14% (60 min/d) and 24% (94 min/d). The decrease in RT was more pronounced in primiparous than in mature cows. In conclusion, RT is reduced on the day of estrus on average. The RT decrease during estrus was characterized by high variation among cows. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Factors associated with first service conception in artificially inseminated nulliparous Holstein heifers.

PubMed

Donovan, G Arthur; Bennett, Fred L; Springer, Frederick S

2003-06-01

Animal and management factors associated with first service conception in nulliparous dairy heifers were determined in 601 Holstein heifers from a dairy farm in north central Florida. Animal data collected included body weight, height at the withers and tail head, body condition score at 6 months of age and just prior to first artificial insemination (AI), and pelvimetry measurements taken just prior to first AI. Management data included season of first AI, inseminator, service sire, method of estrus detection, whether the estrus of first insemination was induced using prostaglandin F(2alpha) (PGF(2alpha)), and whether the heifer received a modified live virus (MLV) vaccine within 21 days of first insemination. Data were analyzed using multivariable logistic regression. Heifers inseminated in the summer were more than four times less likely to become pregnant to first insemination than heifers bred during the rest of the year (odds ratio (OR)=0.24; 95% CI=0.14, 0.41). Using secondary signs for estrus detection instead of standing estrus resulted in significantly reduced odds of conception to first service (OR=0.37; 95% CI 0.13, 1.02). Also, heifers inseminated at estrus induced by PGF(2alpha) were approximately one-third less likely to conceive than those heifers inseminated to a naturally occurring estrus (OR=0.66; 95% CI 0.46, 0.95). An interaction between pelvic size and breeding season was found indicating that large pelvic size had a significant positive effect on fertility in the summer, but was not associated with conception to first service in the winter.

Progesterone plus PMSG Priming in seasonally anovulatory lactating Sarda ewes exposed to the ram effect.

PubMed

Todini, Luca; Malfatti, Alessandro; Barbato, Olimpia; Costarelli, Silva; Debenedetti, Alessandro

2007-04-01

The aim of this trial was to evaluate the effectiveness (fertility and lambing) of priming with a single injection of progesterone plus PMSG in anovulatory lactating Sarda ewes subjected to the ram effect (RE) in spring. Thirty ewes (P4 group) were i.m. injected with 30 mg progesterone and 500 IU PMSG 36 h before ram introduction (d 0). This treatment was compared to a 12-day treatment with fluorogestone acetate intravaginal sponges that was followed by injections of 350 IU PMSG upon sponge withdrawal (FGA group, n=30). All ewes responded to RE, showing plasma progestrone concentrations >1 ng/mL between d 6 and 12 (FGA) or 6 and 9 (P4). Eighty-nine percent of the P4 ewes conceived at first ovulation, and 11% conceived following a short estrus cycle. Lambings occurred on d 150.4 +/- 3.9, and the lambing rate was 100%. The fertility of the FGA ewes was 83% for the induced ovulation and was 7% for the second ovulation after a normal cycle. The FGA ewes lambed on d 149.8 +/- 4.4, and the lambing rate was 83%. Two abortions were recorded for the FGA ewes, which had higher prolificacy than the P4 group (2.2 +/- 0.8 vs. 1.8 +/- 0.4, respectively; P<0.05). Both fertility and the lambing rate were high in both groups, with a high degree of estrus synchronization, and there were no significant differences between the groups. We concluded that priming of lactating Sarda ewes in spring with P4+PMSG before RE is an effective and competitive method (cheaper and more practical than FGA+PMSG) of inducing fertile ovulations in these ewes.

Effects of excess metabolizable protein on ovarian function and circulating amino acids of beef cows: 2. Excessive supply in varying concentrations from corn gluten meal.

PubMed

Geppert, T C; Meyer, A M; Perry, G A; Gunn, P J

2017-04-01

In the dairy industry, excess dietary CP is consistently correlated with decreased conception rates. However, amount of excess CP effects on reproductive function in beef cattle is largely undefined. The objective of this experiment was to determine the effects of excess metabolizable protein (MP) supplementation from a moderately abundant rumen undegradable protein (RUP) source (corn gluten meal: 62% RUP) on ovarian function and circulating amino acid (AA) concentrations in beef cows consuming low quality forage. Non-pregnant, non-lactating beef cows (n=16) were allocated by age, BW and body condition score (BCS) to 1 of 2 isocaloric supplements designed to maintain BW for 60 days. Cows had ad libitum access to corn stalks and were individually offered a corn gluten meal-based supplement daily at 125% (MP125) or 150% (MP150) of National Research Council (NRC) MP requirements. After a 20-day supplement adaptation period, cows were synchronized for ovulation. After 10 days of synchronization, follicular growth was reset with gonadotropin releasing hormone. Daily thereafter, transrectal ultrasonography was performed to diagram ovarian follicular waves, and blood samples were collected for hormone, metabolite and AA analyses. After 7 days of observation of estrus, corpus luteum (CL) size was determined via ultrasound. Data were analyzed using the MIXED procedures of SAS. No differences (P⩾0.21) in BW and BCS existed throughout the study; however, plasma urea N at ovulation was greater (P=0.04) in MP150. Preovulatory ovarian follicle size at dominance, duration of dominance, size at spontaneous luteolysis, length of proestrus and wavelength were not different (P⩾0.11) between treatments. However, ovulatory follicles were larger (P=0.04) and average antral follicle count was greater (P=0.01) in MP150 than MP125. Estradiol concentration and ratio of estradiol to ovulatory follicle volume were not different due to treatment (P⩾0.25). While CL volume 7 days post-estrus was greater (P<0.01) in MP150 than MP125, circulating progesterone 7 days post-estrus and ratio of progesterone to CL volume were not different (P⩾0.21). Total AA were not different (P⩾0.76) at study initiation or completion; however, as a percent of total AA, branched-chain AA at ovulation were greater (P=0.02) in MP150. In conclusion, supplementation of CP at 150% of NRC MP requirements from a moderately undegradable protein source may enhance growth of the ovulatory follicle and subsequent CL compared with MP supplementation at 125% of NRC MP requirements.

Effectiveness of intravaginal progesterone inserts and FSH for inducing synchronized estrus and increasing lambing rate in anestrous ewes.

PubMed

Knights, M; Hoehn, T; Lewis, P E; Inskeep, E K

2001-05-01

The objectives of this study were to determine whether a new progesterone (P4)-releasing intravaginal insert would induce fertile estrus and whether FSH combined with the insert would increase prolificacy in anestrous ewes introduced to rams. Ewes of mixed breeding on six farms were assigned to four randomized treatments: control (C), n = 73; 12 d P4 (polycapralactone [PCL] insert with 0.82 g P4), (P12), n = 73; 12 d P4 plus i.m. FSH (Folltropin, 55 mg NIH-FSH-P1 equivalent) in propylene glycol, 24 h before insert removal, (P12F), n = 71; and 5 d P4 plus FSH (P5F), n = 77. Growth and ovulation of follicles were observed ultrasonographically in 20 ewes at four farms (five/treatment) at insert removal and 36, 48, 72, and 96 h later. Intact rams (1:15 ewes in multiple-sire groups) were joined at insert removal, and raddle marks were observed every 12 h for 5 d. On d 26 to 30, rams were removed; ewes were examined for pregnancy then and 20 d later. Percentage of ewes marked by rams was greater in P4-treated (66 to 79%) than in C (12%; P < 0.01) ewes and in P5F (79%) than in P12F (66%; P < 0.05). Diameters of largest follicles at insert removal were greater (P < 0.05) in P4-treated (5.5 +/- 0.2) than in C ewes (4.8 +/- 0.2). Progesterone increased numbers of follicles > 3 mm (P < 0.01) or ovulated (P < 0.05; 2.6 +/- 0.6 vs 1.3 +/- 0.6 in C ewes) and FSH increased number of follicles > 3 mm (P < 0.05). In FSH-treated ewes, ovulation rate tended to be greater after treatment with P4 for 5 than for 12 d (P = 0.09, 3.3 +/- 0.6 and 2.2 +/- 0.4, respectively). More P4-treated than C ewes lambed (P < 0.01) to the first (38 to 45 vs 0%) or both (63 to 66 vs 41%) service periods. Prolificacy (first service) did not differ between FSH-treated ewes (P12F + P5F; 1.8 +/- 0.1) and ewes treated with P4 only (P12; 1.6 +/- 0.1). However, FSH increased prolificacy to first service (1.8 +/- 0.1) over prolificacy to second service (C ewes 1.5 +/- 0.1; P < 0.05, and all ewes 1.4 +/- 0.1; P < 0.01). Pregnancy retention did not differ among treatments but was greater (P < 0.01) in ewes that conceived at the first (90.9 +/- 3.7) than at the second (72.5 +/- 3.3) service period. In conclusion, a PCL insert in combination with ram introduction at insert removal was more effective than ram introduction alone to induce synchronized estrus and ovulation and to yield pregnancy after one or two service periods. Treatment with P4 for 5 d was as effective as for 12 d to induce fertile estrus in FSH-treated anestrous ewes.

The use of infrared thermography to detect the stages of estrus cycle and ovulation time in anatolian shepherd dogs.

PubMed

Olğaç, Kemal Tuna; Akçay, Ergun; Çil, Beste; Uçar, Burak Mehmet; Daşkın, Ali

2017-01-01

The aim of the study is to evaluate the effectiveness of thermographic monitoring, using the temperature changes of perianal and perivulvar areas for the determination of estrus in Anatolian Shepherd bitches. Fifteen bitches were used in the study. Blood and vaginal smear samples were collected and thermographic monitoring of perianal and perivulvar areas were carried out starting from proestrus to early diestrus. Also, external signs of estrus were investigated. Smear samples were evaluated by light microscopy after Diff-Quik staining method and superficial and keratinized superficial cells were determined as percentage (S + KS%). Progesterone and luteinizing hormone measurements were done by radioimmunoassay. The difference in temperature between perianal and perivulvar areas was evaluated through thermographic images by FLIR ResearchIR Software. According to the results obtained from the study, differences between progesterone and S + KS% were statistically significant ( P  < 0,05). Although temperature showed increase and decrease with progesterone and S + KS%, the differences were not important statistically ( P  > 0,05). Serum luteinizing hormone levels did not sign any difference ( P  > 0,05). As a result, thermographic monitoring alone is not enough for estrus detection in Anatolian Shepherd bitches. However, it can be used to assist the actual estrus detection technique in terms of providing some foreknowledge by evaluating the differences in temperature.

Effects of progestagens and prostaglandin analogues on ovarian function and embryo viability in sheep.

PubMed

Gonzalez-Bulnes, A; Veiga-Lopez, A; Garcia, P; Garcia-Garcia, R M; Ariznavarreta, C; Sanchez, M A; Tresguerres, J A F; Cocero, M J; Flores, J M

2005-06-01

Current study assessed differences in the response of sheep to estrus synchronization either by the administration of two doses of prostaglandin or by the insertion of an intravaginal progestagen sponge. The preovulatory follicular dynamics and estradiol secretion, the ovulatory response and progesterone secretion and the number and quality of embryos were studied in 27 ewes treated with two doses of 100 microg of cloprostenol, 10 days apart, and in 29 sheep treated with progestagen sponges for 14 days. Percentage of sheep responding to the synchronization treatments with signs of estrus behaviour was similar between both groups (81.5% versus 72.4%, respectively). The use of progestagen resulted in a higher diameter of the largest follicle (6.6+/-0.2 versus 5.9+/-0.2, P<0.05), and a lower number of small (6.7+/-0.3 versus 9.6+/-0.4, P<0.005) and total follicles (10.3+/-0.3 versus 12.9+/-0.4, P<0.005). However, mean plasma estradiol concentration during the follicular phase was higher in cloprostenol treated sheep (P<0.005). The mean ovulation rate was similar in both treatments (1.7+/-0.2 versus 1.7+/-0.3), but progesterone concentration during the early luteal phase was again higher in sheep treated with cloprostenol (P<0.05). The mean number of retrieved oocytes/embryos was very similar in both treatments (1.2+/-0.2 versus 1.4+/-0.2) and showed similar fertilization rates (70.6% versus 66.7%), but, although differences did not reach statistical significance, final viability rate was higher in cloprostenol than in progestagen treated ewes (58.9% versus 46.1%, P=0.07). Current results give new evidences supporting the negative effects of progestagens on the functionality of ovulatory follicles and support the development of new protocols for assisted reproduction including the use of prostaglandin analogues.

A single dose of bovine somatotropin 5 days before the end of progestin-based estrous synchronization increases prolificacy in sheep.

PubMed

Carrillo, F; Hernández-Cerón, J; Orozco, V; Hernández, J A; Gutiérrez, C G

2007-11-01

Bovine somatotropin (bST) enhances ovarian follicular and embryonic development in sheep and cattle. In the present study, the objective was to assess whether bST given 5 days before the end of progestin-based estrous synchronization improves prolificacy and lambing rate in sheep. Pelibuey ewes (n=92) exhibiting estrous cycles at regular intervals received an intravaginal sponge containing 45mg of FGA for 12 days. Five days before sponge withdrawal, ewes were treated with either 125mg of bST sc (bST group; n=47) or saline solution (control; n=45). After the sponge was removed, ewes were observed for estrus and subsequently mated twice. Lambing rate and prolificacy was determined at birth. Blood samples were taken from the time of treatment until day 15 after estrus in eight ewes from the bST group and nine from the control group. Concentrations of IGF-I were determined by immunoradiometric assay and progesterone by RIA. Treatment with bST increased (P<0.01) the proportion of ewes with more than one lamb (bST, 56% compared with control, 26%) and prolificacy (bST, 1.6 compared with control, 1.3). Treatment with bST increased (P<0.05) the lambing rate of multiparous (bST, 92% compared with control, 67%) but not in ewes at the first time they were mated (bST, 71% compared with control, 87%; P>0.05). IGF-I concentrations were greater (P<0.01) in ewes treated with bST than in control ewes from 2 days after treatment. Progesterone concentrations did not vary (P>0.05) between groups. It is concluded that a single dose of bST 5 days before progestin withdrawal increases lambing rate and prolificacy in sheep. These effects are associated with an increase in circulating concentrations of IGF-I.

Effect of GnRH treatment on ovarian activity and reproductive performance of low-prolific Rahmani ewes.

PubMed

Hashem, N M; El-Azrak, K M; Nour El-Din, A N M; Taha, T A; Salem, M H

2015-01-15

This study was designed to evaluate the effect of GnRH treatment during different times of the reproductive cycle on ovarian activity, progesterone (P4) concentration, and subsequent fertility of low-prolific, subtropical, Rahmani ewes during breeding season. Forty-five ewes were synchronized for estrus using a double injection of 0.5 mL of PGF2α agonist (125-μg cloprostenol), 11 days apart. Ewes showing estrus (Day 0) were treated with 1 mL of GnRH agonist (4-μg buserelin) on the day of estrus (GnRH0, n = 12) or 7 days post-mating (GnRH7, n = 10) or on both days (GnRH0+7, n = 11) or not (control, n = 12). Ovarian response to the treatment and diagnosis of pregnancy were ultrasonographically monitored. Also, serum P4 concentration was determined weekly throughout 28 days post-mating. Results showed that neither total number of follicles nor their populations were changed on Day 0 or 7 days post-mating by the GnRH treatment. GnRH treatment on Day 0 or Day 7 post-mating or both days did not enhance ovulation rate compared with the control. The mean numbers of accessory CL increased (P < 0.05) in the GnRH7 group than those in the control and GnRH0 groups, whereas it was intermediate in the GnRH0+7 group. The greatest (P < 0.05) overall mean of serum P4 concentration was for the GnRH7 and GnRH0+7 groups, followed by the GnRH0 and control groups. Serum P4 concentration increased (P < 0.05) on Day 14 post-mating and continued higher (P < 0.05) until Day 28 post-mating in the GnRH7 and GnRH0+7 groups compared with the control. Regardless of the time of GnRH administration, GnRH treatment reduced (P < 0.05) pregnancy loss from Day 40 post-mating to parturition and tended to enhance (P < 0.20) lambing rate compared with the control. In conclusion, a single dose of GnRH at the time of estrus or 7 days post-mating could be used as an effective protocol to decrease pregnancy loss from Day 40 after mating to parturition in low-prolific Rahmani ewes. Copyright © 2015 Elsevier Inc. All rights reserved.

Relationship of follicle size and concentrations of estradiol among cows exhibiting or not exhibiting estrus during a fixed-time AI protocol

USDA-ARS?s Scientific Manuscript database

Cows exhibiting estrus near the time of fixed-time AI had greater pregnancy success than cows showing no estrus. The objective of this study was to determine the relationship between follicle size and peak estradiol concentration between cows that did or did not exhibit estrus during a fixed-time AI...

Influence of gonadotropin-releasing hormone and timing of insemination relative to estrus on pregnancy rates of dairy cattle at first service.

PubMed

Mee, M O; Stevenson, J S; Scoby, R K; Folman, Y

1990-06-01

The objective was to determine the influence of gonadotropin-releasing hormone on pregnancy rates of dairy cattle at first services, when both the timing of hormone injection and insemination were altered relative to the onset of estrus. Cows (n = 325) were assigned randomly to six groups making up a 2 X 2 X 2 incomplete factorial experiment; dose of GnRH (100 micrograms versus saline), timing [1 h (early) or 12 to 16 h (late) after first detected estrus] of AI, and timing of hormone injection (early versus late) were the three main effects. Cows were observed for estrus 4 times daily. Treatments and resulting pregnancy rates were: 1) hormone injection early plus AI early (35%), 2) hormone injection late plus AI early (34%), 3) saline injection early plus AI early (30%), 4) hormone injection late plus AI late (30%), 5) hormone injection early plus AI late (46%), and 6) saline injection late plus AI late (43%). Pregnancy rate in the first four groups (32%) was less than that in the latter two groups (44%). Concentrations of LH in serum were greater for cows given hormone or saline injections in early estrus than for cows injected with either hormone of saline during late estrus. Concentrations of LH in serum 2 h after GnRH were elevated above those of controls, whether GnRH was injected during early or late estrus. Neither concentrations of LH during estrus nor concentrations of progesterone 8 to 14 d after estrus explained the possible antifertility effect of GnRH given during late estrus.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of exogenous gonadotropins on the weaning-to-estrus interval in sows.

PubMed

Estienne, M J; Hartsock, T G

1998-03-01

The efficacy of PG 600 (400 IU PMSG and 200 IU hCG) for accelerating the onset of estrus was determined for sows weaned during the summer. Yorkshire sows (average parity = 4.6), nursing 8.6 +/- 0.2 pigs (mean +/- SEM) were weaned after 27.7 +/- 0.4 d of lactation and were treated intramuscularly with either PG 600 (n = 35) or with 0.9% saline (n = 35). Sows were checked for estrus once daily in the presence of a mature boar. Treatment with PG 600 increased (P < 0.05) the percentage of sows in estrus within 7 d after weaning (97.1 vs 82.9%). Relative to controls, sows given PG 600 expressed estrus sooner (3.8 +/- 0.1 d vs 4.5 +/- 0.1 d; P < 0.01). Sows exhibiting estrus within 7 d after treatments were artificially inseminated 0 and 24 h after first exhibiting estrus. The percentage of inseminated sows that farrowed tended to be higher (P < 0.07) for control than for PG 600-treated sows (96.6 vs 82.3%). The number of pigs born live was similar (P > 0.1) for sows treated with PG 600 and with saline, and was 12.7 +/- 0.6 and 11.7 +/- 0.7, respectively. Pigs farrowed by saline-treated sows, however, tended to be heavier (P < 0.09) than pigs farrowed by sows treated with PG 600 (1.49 +/- 0.06 kg vs 1.34 +/- 0.06 kg). In summary, PG 600 accelerated the onset of estrus in sows weaned during the summer. Sows mated during the induced estrus, however, tended to have a lower farrowing rate and farrowed lighter pigs than control sows inseminated during a natural estrus occurring within 7 d after weaning.

A new approach to enhance reproductive performance in sheep using royal jelly in comparison with equine chorionic gonadotropin.

PubMed

Husein, M Q; Haddad, S G

2006-06-01

The objective was to compare the effects of royal jelly (RJ) and eCG treatments on reproductive performance of ewes synchronized using intravaginal progesterone-releasing devices. Forty-two cycling Awassi ewes were treated intramuscularly (i.m.) with 15 mg PGF2alpha. On the following day, all ewes were administered with CIDR-G for 12 days and were randomly allocated to three (RJ, eCG and control) groups of 14 ewes each. Ewes in the RJ-treated group received daily i.m. treatments of 400mg RJ during the period of CIDR-treatment. Each ewe in the eCG-treated group received an i.m. treatment of 500 IU eCG at the time of CIDR-G removal (day 0) and no further treatment was given to ewes in the control group. Ewes were exposed to four fertile rams for 72 h, from the time of CIDR-G removal, and checked for breeding marks at 6-h intervals. Blood samples were collected from day -13 until day 0 and thereafter until day 19 for progesterone analysis. Royal jelly treatment resulted in a greater rate of decline and lower (P<0.02) progesterone concentrations between days -10 and 0 than eCG-treated and control ewes. Expression of estrus was similar among the three groups and intervals to onset of estrus were shorter (P<0.01) in RJ-treated (31.3h) and eCG-treated (29.8h) than control (41.3h) ewes. First-cycle pregnancy and lambing rates were greater (P<0.05) in RJ-treated (71.4 and 71.4%) and eCG-treated (85.7 and 78.6%) than in control (42.9 and 35.7%) ewes, respectively. Results demonstrate that the treatments of RJ and eCG in conjunction with CIDR-G were similarly effective in induction of estrus and improvement of pregnancy and lambing rates.

Male hamsters discriminate estrous state from vaginal secretions and individuals from flank marks

PubMed Central

delBarco-Trillo, Javier; LaVenture, Alex B.; Johnston, Robert E.

2009-01-01

It is clear that male hamsters discriminate between the odors of individual, conspecific females, as shown by using habituation-dishabituation methods. However, it is not clear from past research whether male hamsters are able to discriminate between the odors of estrous and non-estrous females. A series of habituation-dishabituation experiments were conducted to determine whether males discriminated between different estrous cycle states using two female secretions, those from flank glands and vaginal secretions. We found that, when habituated to a female flank-gland secretion, males discriminated between this female and a second female on the test trial, whether both were in estrus, both were in diestrus, or one was in estrus and the other in diestrus. There was no difference, however, in the magnitude of their dishabituation response toward flank-gland odors of females in estrus and diestrus. These results suggest that males use flank-gland odors to gain information primarily about individuals. When tested with vaginal secretions in habituation-dishabituation tests, males only showed differences in investigation when the second female was in estrus, indicating that males use vaginal secretions to gain information primarily about reproductive state. PMID:19615611

Male hamsters discriminate estrous state from vaginal secretions and individuals from flank marks.

PubMed

delBarco-Trillo, Javier; LaVenture, Alex B; Johnston, Robert E

2009-09-01

It is clear that male hamsters discriminate between the odors of individual, conspecific females, as shown by using habituation-dishabituation methods. However, it is not clear from past research whether male hamsters are able to discriminate between the odors of estrous and non-estrous females. A series of habituation-dishabituation experiments was conducted to determine whether males discriminated between different estrous cycle states using two female secretions, those from flank-glands and vaginal secretions. We found that, when habituated to a female flank-gland secretion, males discriminated between this female and a second female on the test trial, whether both were in estrus, both were in diestrus, or one was in estrus and the other in diestrus. There was no difference, however, in the magnitude of their dishabituation response toward flank-gland odors of females in estrus and diestrus. These results suggest that males use flank-gland odors to gain information primarily about individuals. When tested with vaginal secretions in habituation-dishabituation tests, males only showed differences in investigation when the second female was in estrus, indicating that males use vaginal secretions to gain information primarily about reproductive state.

Effect of Aegle marmelos and Murraya koenigii in treatment of delayed pubertal buffaloes heifers

PubMed Central

Baitule, Mohan M.; Gawande, A. P.; Kumar, Umesh; Sahatpure, S. K.; Patil, Manoj S.; Baitule, Mansi M.

2016-01-01

Aim: This study aims to study the estrus induction, ovulation, and conception rate of delayed puberty in buffaloes heifers by feeding a herbal plants Aegle marmelos (bael/bili/bhel leaf) and Murraya koenigii (Curry leaf). Materials and Methods: Totally, 24 buffalo heifers with delayed puberty were selected for the present study and divided randomly in four equal groups (n=6). Before experiment, all animals were dewormed with albendazole at 10 mg/kg body weight to prevent them from the stress of parasitism. In the present experiment, four group taken and Group I (n=6) treated with A. marmelos, Group II (n=6) treated with M. koenigii, Group III (n=6) treated with mixture of A. marmelos and M. koenigii and fed for 9 days. Group IV (n=6) considered as control and fed with concentrate only. The blood samples were collected from all the animals on day 0 (before treatment), 4, 9 (during treatment), on the day of estrus and day 8 after the onset of estrus. The 10 ml blood was collected from the jugular vein of all the experimental animals for estimation of serum calcium, inorganic phosphorus, and progesterone (P4). The estrus response, ovulation, conception rate along with serum calcium, inorganic phosphorus, and progesterone level were determined by the standard protocol. Results: From Group III 4 heifers, from Group II 3 heifers, and from Group I and IV (Control) 2 heifers each, exhibited the estrus. The estrus response was recorded as 33.33%, 50.00%, 75.00%, and 33.33% in Group I, Group II, Group III, and Group IV, respectively. In treatment Group III, serum calcium found significantly more (p<0.05) on day 8 post-estrus as compared to other groups at a similar interval. Inorganic phosphorus and progesterone show no significant difference between groups. The ovulation and conception rates are comparatively better in Group III (75%) buffalo heifers than other groups. Conclusion: Herbal supplementation of A. marmelos and M. koenigii in combination, as well as M. koenigii alone, were found effective in fertility improvement in delayed pubertal buffalo heifers by increasing ovulation and conception rate. PMID:28096608

Pineal and ovarian response to 22- and 24-h days in the ewe.

PubMed

English, J; Arendt, J; Symons, A M; Poulton, A L; Tobler, I

1988-08-01

Melatonin secretion in ewes was entrained by 22-h light-dark cycles whether of long (16L:6D) or short (6L:16D) photoperiod. In photoperiods of 6L:16D, a phase-delay of melatonin secretion was evident, leading to a dark-phase duration shorter than that found in 8L:16D. Early onset of estrus was induced in anestrous ewes kept in 8L:16D, but not 6L:16D, from 22 July compared to controls in natural light. In photoperiods of 16L:6D, the melatonin profile corresponded precisely to the dark phase. Early offset of estrus was induced in estrous ewes kept in both 18L:6D and 16L:6D from 18 December compared to controls in natural light. Thus, when the duration of melatonin secretion was appropriate to the long photoperiod (16L:6D), but with a constantly changing phase position, a long-day reproductive response was found. Activity-rest cycles were not entrained by 16L:6D; thus the synchronization of melatonin and activity-rest cycles does not appear to be essential for the induction of a long-day reproductive response. These results support the hypothesis that the duration, not the circadian-phase position, of melatonin is critical to the induction of photoperiodic effects.

Persistent estrus rat models of polycystic ovary disease: an update.

PubMed

Singh, Krishna B

2005-10-01

To critically review published articles on polycystic ovary (PCO) disease in rat models, with a focus on delineating its pathophysiology. Review of the English-language literature published from 1966 to March 2005 was performed through PubMed search. Keywords or phrases used were persistent estrus, chronic anovulation, polycystic ovary, polycystic ovary disease, and polycystic ovary syndrome. Articles were also located via bibliographies of published literature. University Health Sciences Center. Articles on persistent estrus and PCO in rats were selected and reviewed regarding the methods for induction of PCO disease. Changes in the reproductive cycle, ovarian morphology, hormonal parameters, and factors associated with the development of PCO disease in rat models were analyzed. Principal methods for inducing PCO in the rat include exposure to constant light, anterior hypothalamic and amygdaloidal lesions, and the use of androgens, estrogens, antiprogestin, and mifepristone. The validated rat PCO models provide useful information on morphologic and hormonal disturbances in the pathogenesis of chronic anovulation in this condition. These studies have aimed to replicate the morphologic and hormonal characteristics observed in the human PCO syndrome. The implications of these studies to human condition are discussed.

Spectral pattern of urinary water as a biomarker of estrus in the giant panda

NASA Astrophysics Data System (ADS)

Kinoshita, Kodzue; Miyazaki, Mari; Morita, Hiroyuki; Vassileva, Maria; Tang, Chunxiang; Li, Desheng; Ishikawa, Osamu; Kusunoki, Hiroshi; Tsenkova, Roumiana

2012-11-01

Near infrared spectroscopy (NIRS) has been successfully used for non-invasive diagnosis of diseases and abnormalities where water spectral patterns are found to play an important role. The present study investigates water absorbance patterns indicative of estrus in the female giant panda. NIR spectra of urine samples were acquired from the same animal on a daily basis over three consecutive putative estrus periods. Characteristic water absorbance patterns based on 12 specific water absorbance bands were discovered, which displayed high urine spectral variation, suggesting that hydrogen-bonded water structures increase with estrus. Regression analysis of urine spectra and spectra of estrone-3-glucuronide standard concentrations at these water bands showed high correlation with estrogen levels. Cluster analysis of urine spectra grouped together estrus samples from different years. These results open a new avenue for using water structure as a molecular mirror for fast estrus detection.

Spectral pattern of urinary water as a biomarker of estrus in the giant panda.

PubMed

Kinoshita, Kodzue; Miyazaki, Mari; Morita, Hiroyuki; Vassileva, Maria; Tang, Chunxiang; Li, Desheng; Ishikawa, Osamu; Kusunoki, Hiroshi; Tsenkova, Roumiana

2012-01-01

Near infrared spectroscopy (NIRS) has been successfully used for non-invasive diagnosis of diseases and abnormalities where water spectral patterns are found to play an important role. The present study investigates water absorbance patterns indicative of estrus in the female giant panda. NIR spectra of urine samples were acquired from the same animal on a daily basis over three consecutive putative estrus periods. Characteristic water absorbance patterns based on 12 specific water absorbance bands were discovered, which displayed high urine spectral variation, suggesting that hydrogen-bonded water structures increase with estrus. Regression analysis of urine spectra and spectra of estrone-3-glucuronide standard concentrations at these water bands showed high correlation with estrogen levels. Cluster analysis of urine spectra grouped together estrus samples from different years. These results open a new avenue for using water structure as a molecular mirror for fast estrus detection.

Spectral pattern of urinary water as a biomarker of estrus in the giant panda

PubMed Central

Kinoshita, Kodzue; Miyazaki, Mari; Morita, Hiroyuki; Vassileva, Maria; Tang, Chunxiang; Li, Desheng; Ishikawa, Osamu; Kusunoki, Hiroshi; Tsenkova, Roumiana

2012-01-01

Near infrared spectroscopy (NIRS) has been successfully used for non-invasive diagnosis of diseases and abnormalities where water spectral patterns are found to play an important role. The present study investigates water absorbance patterns indicative of estrus in the female giant panda. NIR spectra of urine samples were acquired from the same animal on a daily basis over three consecutive putative estrus periods. Characteristic water absorbance patterns based on 12 specific water absorbance bands were discovered, which displayed high urine spectral variation, suggesting that hydrogen-bonded water structures increase with estrus. Regression analysis of urine spectra and spectra of estrone-3-glucuronide standard concentrations at these water bands showed high correlation with estrogen levels. Cluster analysis of urine spectra grouped together estrus samples from different years. These results open a new avenue for using water structure as a molecular mirror for fast estrus detection. PMID:23181188

Using estrus detection patches to optimally time insemination improved pregnancy risk in suckled beef cows enrolled in a fixed-time artificial insemination program.

PubMed

Hill, S L; Grieger, D M; Olson, K C; Jaeger, J R; Dahlen, C R; Bridges, G A; Dantas, F; Larson, J E; Muth-Spurlock, A M; Ahola, J K; Fischer, M C; Perry, G A; Larimore, E L; Steckler, T L; Whittier, W D; Currin, J F; Stevenson, J S

2016-09-01

A multilocation study examined pregnancy risk (PR) after delaying AI in suckled beef cows from 60 to 75 h when estrus had not been detected by 60 h in response to a 7-d CO-Synch + progesterone insert (CIDR) timed AI (TAI) program (d -7: CIDR insert concurrent with an injection of GnRH; d 0: PGF injection and removal of CIDR insert; and GnRH injection at TAI [60 or 75 h after CIDR removal]). A total of 1,611 suckled beef cows at 15 locations in 9 states (CO, IL, KS, MN, MS, MT, ND, SD, and VA) were enrolled. Before applying the fixed-time AI program, BCS was assessed, and blood samples were collected. Estrus was defined to have occurred when an estrus detection patch was >50% colored (activated). Pregnancy was determined 35 d after AI via transrectal ultrasound. Cows ( = 746) detected in estrus by 60 h (46.3%) after CIDR removal were inseminated and treated with GnRH at AI (Control). Remaining nonestrous cows were allocated within location to 3 treatments on the basis of parity and days postpartum: 1) GnRH injection and AI at 60 h (early-early = EE; = 292), 2) GnRH injection at 60 h and AI at 75 h (early-delayed = ED; = 282), or 3) GnRH injection and AI at 75 h (delayed-delayed = DD; = 291). Control cows had a greater ( < 0.01) PR (64.2%) than other treatments (EE = 41.7%, ED = 52.8%, DD = 50.0%). Use of estrus detection patches to delay AI in cows not in estrus by 60 h after CIDR insert removal (ED and DD treatments) increased ( < 0.05) PR to TAI when compared with cows in the EE treatment. More ( < 0.001) cows that showed estrus by 60 h conceived to AI at 60 h than those not showing estrus (64.2% vs. 48.1%). Approximately half (49.2%) of the cows not in estrus by 60 h had activated patches by 75 h, resulting in a greater ( < 0.05) PR than their nonestrous herd mates in the EE (46.1% vs. 34.5%), ED (64.2% vs. 39.2%), and DD (64.8% vs. 31.5%) treatments, respectively. Overall, cows showing estrus by 75 h (72.7%) had greater ( < 0.001) PR to AI (61.3% vs. 37.9%) than cows not showing estrus. Use of estrus detection patches to allow for a delayed AI in cows not in estrus by 60 h after removal of the CIDR insert improved PR to TAI by optimizing the timing of the AI in those cows.

Synchronization of follicular wave emergence in the seasonally anestrous ewe: the effects of estradiol with or without medroxyprogesterone acetate.

PubMed

Barrett, D M W; Bartlewski, P M; Duggavathi, R; Davies, K L; Huchkowsky, S L; Epp, T; Rawlings, N C

2008-04-15

Fertility is often lower in anestrous compared to cyclic ewes, after conventional estrus synchronization. We hypothesized that synchronization of ovarian follicular waves and ovulation could improve fertility at controlled breeding in anestrous ewes. Estradiol-17beta synchronizes follicular waves in cattle. The objectives of the present experiments were to study the effect of an estradiol injection, with or without a 12-d medroxyprogesterone acetate (MAP) sponge treatment, on synchronization of follicular waves and ovulation in anestrous ewes. Twenty ewes received sesame oil (n=8) or estradiol-17beta (350 microg; n=12). Eleven ewes received MAP sponges for 12d and were treated with oil (n=5) or estradiol-17beta (n=6) 6d before sponge removal. Saline (n=6) or eCG (n=6) was subsequently given to separate groups of ewes at sponge removal in the MAP/estradiol-17beta protocol. Estradiol treatment alone produced a peak in serum FSH concentrations (4.73+/-0.53 vs. 2.36+/-0.39 ng/mL for treatment vs. control; mean+/-S.E.M.) after a short-lived (6 h) suppression. Six of twelve ewes given estradiol missed a follicular wave around the time of estradiol injection. Medroxyprogesterone acetate-treated ewes given estradiol had more prolonged suppression of serum FSH concentrations (6-18 h) and a delay in the induced FSH peak (32.3+/-3.3 vs. 17.5+/-0.5 h). Wave emergence was delayed (5.7+/-0.3 vs. 1.4+/-0.7d from the time of estradiol injection), synchronized, and occurred at a predictable time (5-7 vs. 0-4d) compared to ewes given MAP alone. All ewes given eCG ovulated 3-4d after injection; this predictable time of ovulation may be efficacious for AI and embryo transfer.

Gonadotropin-releasing hormone increased pregnancy risk in suckled beef cows not detected in estrus and subjected to a split-time artificial insemination program.

PubMed

Hill, S L; Grieger, D M; Olson, K C; Jaeger, J R; Dahlen, C R; Crosswhite, M R; Pereira, N Negrin; Underdahl, S R; Neville, B W; Ahola, J; Fischer, M C; Seidel, G E; Stevenson, J S

2016-09-01

We hypothesized that GnRH would increase pregnancy risk (PR) in a split-time AI program for cows in which estrus was not detected. A total of 1,236 suckled beef cows at 12 locations in 3 states (Colorado, Kansas, and North Dakota) were enrolled. Before applying the fixed-time AI program, BCS was assessed. Cows were treated on d -7 with a progesterone insert concurrent with 100 μg GnRH and on d 0 with 25 mg PGF plus removal of the insert. Estrus-detection patches were affixed to cows at insert removal. Estrus was defined to have occurred when an estrus-detection patch was >50% colored (activated). Cows in estrus by 65 h ( = 758; 61.3% of all cows) were randomly allocated to 2 treatments: 1) 100 μg GnRH and early + GnRH (E+G; = 373) or 2) AI only at 65 h (early - no GnRH [E-G]; = 385). The remaining cows were randomly allocated to 2 treatments: 1) 5(L+G; = 252) or 2) AI only at 84 h (late no GnRH [L-G]; = 226). Pregnancy was determined 35 d after AI via transrectal ultrasound. Pregnancy risk did not differ ( = 0.68) between E+G and E-G cows (61.9 vs. 60.4%, respectively). Conversely, for cows inseminated at 84 h, PR was greater ( = 0.01) in cows that received GnRH (L+G) compared with their herd mates not receiving GnRH (L- G; 41.7 vs. 30.8%, respectively). Of those cows not detected in estrus by 65 h, 42.1% were detected by 84 h, for a total expression of estrus by all cows of 77.6%. Administration of GnRH increased ( < 0.01) PR in cows not detected in estrus by 84 h (+GnRH = 33.4% [ = 146] vs. no GnRH = 15.0% [ = 128]) but had no effect in cows expressing estrus by 84 h (+GnRH = 65.3% [ = 103] vs. no GnRH = 61.7% [ = 97]). Neither estrus expression by 65 or 84 h nor PR was influenced by BCS, parity, or days postpartum at AI. Cows had greater PR when they had been detected in estrus before AI, and PR was improved by administration of GnRH at 65 h after insert removal in cows that were not detected in estrus and inseminated at 84 h.

Effect of season, month of parturition and lactation on estrus behavior and ovarian activity in Barki x Rahmani crossbred ewes under subtropical conditions.

PubMed

Hashem, N M; El-Zarkouny, S Z; Taha, T A; Abo-Elezz, Z R

2011-04-15

The correlations between some meteorological parameters and fertility data were evaluated in Barki x Rahmani crossbred ewes using the records of five consecutive years (2003-2007). Additionally, estrus detection and ultrasonic evaluation were applied on eighteen mature dry ewes during breeding and non-breeding seasons. The effect of lactation was evaluated by monitoring estrus behavior in ninety four lactating ewes from 40 to 120 d after parturition. Moreover, ultrasonography was used to identify ovarian activity in six cyclic and six acyclic non-lactating ewes. Results revealed that relative estrus occurrence and fertile mating were positively correlated (P <0.05) with high temperature and long photoperiod (conditions of summer season), and were negatively correlated (P < 0.01) with rainfall (condition of winter season). During breeding season, estrus rate, serum progesterone concentration, and diameter of largest follicle were significantly (P < 0.05) higher than those observed during the non-breeding season. Furthermore, month of parturition had a significant effect (P < 0.05) on estrus rate of lactating ewes where ewes that lambed in August, September, and October recorded higher estrus rate than those lambed in November and December. However, the lactational strength did not exert any deleterious effect on the reproductive performance of lactating ewes. In conclusion, in Egypt under subtropical conditions, Barki x Rahmani crossbred ewes exerted optimum estrus behavior and fertile mating during summer season. The reduction in estrus activity during lactation was due to the seasonal effect rather than lactational stress. Copyright © 2011 Elsevier Inc. All rights reserved.

Short communication: Comparison of estrus characteristics in Holstein heifers by 2 activity monitoring systems.

PubMed

Silper, B F; Madureira, A M L; Kaur, M; Burnett, T A; Cerri, R L A

2015-05-01

Two activity monitoring systems-Heatime (SCR Engineers Ltd., Netanya, Israel) and IceTag (IceRobotics Ltd., Edinburgh, UK)-were compared on their ability to detect and quantify estrus expression. Holstein heifers (n=57) were fitted with Heatime (HT) and IceTag (IT) sensors from 12 mo of age until confirmation of pregnancy. Upon detection of high activity by HT, ovaries were scanned by ultrasound, a blood sample was collected for analysis of plasma estradiol, and signs of estrus (clear vaginal mucus, uterine muscle tone, visual mounting activity, standing to be mounted, or rump showing signs of repeated acceptance of mounts) were recorded. Because only estrus episodes detected by HT (n=111) were further evaluated, only the positive predictive value was measured. Heifers were housed in groups of 24 in a freestall pen. Data were analyzed using Proc CORR and GLM of SAS (SAS Institute Inc., Cary, NC). The positive predictive value was 84.7% (94/111) for HT and 98.7% (74/75) for IT. Estrus duration was recorded by HT as 14.3±4.1h [mean ± standard deviation (SD)] and by IT as 15.0±4.0h; duration measurements were correlated (r=0.60). The mean duration difference was 0.74±3.52h. Recordings of onset and end of estrus by IT were 3.5±4.3h and 2.9±4.9h earlier than those by HT. The overlap in duration was 9h. Measurements of estrus intensity were correlated (r=0.63). Peak activity was 77.3±19.5 index value (approximately 7.7 SD from basal activity) on HT. The relative increase in activity measured by IT was 360±170% baseline value. Measurements of intensity and duration from HT were correlated (r=0.64) but those from IT were not (r=0.13). Plasma estradiol concentration (11.2±4.6pg/mL) was not correlated with preovulatory follicle diameter or with duration or intensity of estrus. Diameter of preovulatory follicle (15.7±2.6mm) had no correlation with duration of estrus and was only weakly correlated with intensity measured by either system. Baseline steps/hour was negatively correlated with intensity from both sensors (r=-0.37 and -0.70 for HT and IT). Estrus episodes accompanied by 2 or 3 of the monitored signs of estrus had greater intensity and duration on HT but not on IT. Preovulatory follicle diameter and plasma estradiol concentration did not influence occurrence of estrus signs. Results indicate that both systems identified estrus precisely, with correlated characterization and similar timing. In contrast, relationships with plasma estradiol concentration and signs of estrus require further investigation. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

[Differences in the rate of establishment of permanent estrus in rats after autotransplantation of the ovaries and as affected by other conditions].

PubMed

Smetanina, M D; Vunder, P A

1985-09-01

In adult female rats, constant light leads to the cessation of the sexual cycle and formation of permanent estrus after 6 to 7 days. In young animals, the sexual cycle was retained despite constant light and only after 3 months when the body weight of the rats reached 200-220 g the estrus became permanent. This happened earlier than in animals with the ovaries autotransplanted to the ears. The combination of constant light and autotransplantation of the ovaries caused an earlier formation of permanent estrus. It is marked that the same mechanism (the age-associated decrease of the cyclic center sensitivity to estrogen) underlies permanent estrus of various etiology.

Relationship between electrical resistance of cervical mucus and ovarian steroid concentration at the time of artificial insemination in ewes.

PubMed

Theodosiadou, Ekaterini; Amiridis, Georgios S; Tsiligianni, Theodora

2014-09-01

The purpose of this study was to investigate whether fertile or non-fertile inseminations (AI) in synchronized ewes are correlated with the electrical resistance of cervical mucus (ERCM) and the ovarian steroid concentration. AIs were performed either at fixed-time (group A) or after estrus detection (group B). Retrospective analysis revealed that at AI, pregnant ewes had lower ERCM values and progesterone concentrations than non-pregnant ones (p<0.05). It appears that ERCM may be used as an additional index for fertility enhancement of inseminated ewes. Copyright © 2014 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

The effects of sexual experience and estrus on male-seeking motivated behavior in the female rat

PubMed Central

Nofrey, Barbara; Rocha, Beatriz; Lopez, Hassan H.; Ettenberg, Aaron

2008-01-01

Ovariectomized (OVX) female rats were trained to traverse a straight alley and return to a goal box where they had previously encountered a male rat, a female rat or an empty goal box. The time required to run the alley was used as an index of the subjects’ motivation to re-engage the goal box target. Subjects were tested in both estrus and non-estrus, first sexually naïve and then again after sexual experience. Female rats ran most quickly for a male target, most slowly for an empty goal box, and at intermediate speeds for a female target. Sexual experience tended to slow run times for all but male targets. Estrus enhanced approach behavior for males and an empty goal box, but tended to slow the approach toward females, both before and after sexual experience. This latter finding was further investigated in a second experiment in which sexually naïve OVX females were tested during estrus and non-estrus in a locomotor activity apparatus, a runway with an empty goal box, and an open field. Estrus produced no changes in spontaneous locomotion either in the activity box or the open field, but decreased run times in the alley and increased the number of center-square entries in the open-field. Thus, estrus produces increases in sexual motivation that selectively enhance exploratory, presumably male-seeking behavior, but not simple spontaneous locomotion. PMID:18761024

Characterizing body temperature and activity changes at the onset of estrus in replacement gilts

USDA-ARS?s Scientific Manuscript database

Accurate estrus detection can improve sow conception rates and increase swine production efficiency. Unfortunately, current estrus detection practices based on individual animal behavior may be inefficient due to large sow populations at commercial farms and the associated labor required. Therefore,...

Effects of pre- and post-insemination maternal plane of nutrition on estrus and embryo development [Abstract

USDA-ARS?s Scientific Manuscript database

Nutritional changes immediately after insemination can result in differential embryonic development. Therefore, the objective of this study was to evaluate the impact of a nutritional change immediately before or after AI on estrus expression, interval to estrus, and day 6 embryo recovery, developme...

Correlation between sexual maturation and induction of persistent estrus by continuous illumination.

PubMed

Takeo, Y; Shirama, K; Shimizu, K; Maekawa, K

1975-10-01

The rats brought up under continuous illumination from the neonatal day persist in the rhythmic estrous cycle for long time and do not easily reveal so-called continuous vaginal estrus. On the contrary, immature rats at about 30 days of age show the persistent estrus soon after exposure to continuous illumination as well as adult rats. The purpose of this paper was to examine the relation of the age placed under continuous illumination and the time required to reach the persistent estrus. As the results, it was found that the younger rats need proportionally the longer time to reach the persistent estrus; the rats which were transferred into continuously illuminated environment at 0 (group A), 5 (group B), 10 (group C), 15-16 (group D) and 30 (group E) days of age required a mean time of 132.1 +/- 8.4, 126.8 +/- 8.9, 89.7 +/- 6.2, 91.5 +/- 3.8 and 70.3 +/- 3.0 days after birth to reach the persistent estrus, respectively. In the present data, a significant difference was seen between group B and C. Though all rats were killed after the same length of persistently estrous periods, actual endocrine level appeared to differ among the groups; the rats required longer time to reach the persistent estrus had smaller ovaries and adrenals.

Buffalo cervico-vaginal fluid proteomics with special reference to estrous cycle: heat shock protein (HSP)-70 appears to be an estrus indicator.

PubMed

Muthukumar, Subramanian; Rajkumar, Ramalingam; Karthikeyan, Kandasamy; Liao, Chen-Chung; Singh, Dheer; Akbarsha, Mohammad Abdulkader; Archunan, Govindaraju

2014-05-01

Cervico-vaginal fluid (CVF) plays significant roles in coitus, sperm transport, and implantation. It is believed to be a good noninvasive biomarker for various diagnostic purposes. In this study, a comprehensive proteomic analysis of buffalo CVF was performed during the estrous cycle in order to document the protein expressions, utilizing SDS-PAGE, mass spectrometry, and immunoblot. The main objective was to screen the CVF of buffalo for one or more estrus-specific proteins. A total of 416 proteins were identified in the CVF of both estrus and diestrus phases. Out of these proteins, 68 estrus-specific proteins have been extensively reviewed in the protein database. The major physiological functions of estrus CVF proteins appeared to be stress response, immune response, and metabolic. Eventually, the expression level of heat shock protein-70 in the CVF during the estrus phase, as revealed in SDS-PAGE analysis, was higher than during diestrus. The identity of the protein was confirmed by immunoblot analysis as heat shock protein-70. The findings provide a potential lead for the evaluation of these proteins for estrus detection in buffalo because CVF biomarker detection is a noninvasive technique. The mass spectrometric data of identified proteins have been deposited at the ProteomeXchange with the identifier PXD000620.

Induction of an LH surge and ovulation by buserelin (as Receptal) allows breeding of weaned sows with a single fixed-time insemination.

PubMed

Driancourt, M A; Cox, P; Rubion, S; Harnois-Milon, G; Kemp, B; Soede, N M

2013-09-01

The aim of this study was to demonstrate successful breeding of sows with a single fixed-time insemination following ovulation induction by buserelin, a GnRH analogue. In a first step, the optimal dose of buserelin (6, 10, or 16 μg) injected at 77 hours after weaning was determined in weaned sows (N = 15, 11, and 12, respectively) using its ability to induce an LH surge of similar magnitude as in control sows (N = 15) and induce ovulation. In 29/38 treated sows (76%), ovulation was induced and synchronized between 32 and 44 hours after injection, and the proportion of females ovulating during this time window was similar between groups at 73%, 73%, and 83% (6, 10, or 16 μg, respectively). Interestingly, whereas ovulation of 100% multiparous sows was induced and synchronized in the 32 to 44 hours posttreatment time window, successful induction was achieved in a lower proportion of primiparous sows (50%, 50%, and 67% following 6, 10, or 16 μg, respectively), the dose effect being nonsignificant. The magnitude of the LH surge was similar between control and treated sows, irrespective of the buserelin dose injected. Neither ovulation rate nor the number of good embryos on Day 5 postovulation differed between groups. Interestingly, the frequency of follicular cysts at slaughter was significantly affected by treatment (P < 0.05), being minimal and maximal in sows treated with 10 or 6 μg buserelin, respectively. In a second step, 419 sows from commercial herds in Spain, Germany, and France were randomly allocated to a control or treated group. The control sows were inseminated twice 12 ± 4 hours apart once estrus was detected. Treated sows received 10 μg buserelin at 86 ± 3 hours after weaning and were inseminated once 30 to 33 hours later. Farrowing rate of treated sows (87%, 166/192) was similar to that of control sows (84.5%, 169/200). Litter size was also similar between treated and control sows (13.6 ± 3.8 vs. 13.7 ± 3.2). In multiparous sows, neither duration of lactation nor magnitude of the fat loss during lactation significantly affected treatment effects. It is concluded that ovulation of weaned multiparous sows can be tightly synchronized by buserelin (10 μg) administration at 86 hours postweaning. This allows breeding once at a fixed time following buserelin injection while maintaining reproductive performance at a level similar to that of sows bred twice during estrus. Copyright © 2013 Elsevier Inc. All rights reserved.

The relationship of plasma urea nitrogen with growth traits and age at first estrus in gilts

USDA-ARS?s Scientific Manuscript database

Gilts that reach puberty at an earlier age with more backfat have greater lifetime productivity. Increased growth rates generally promote earlier age at first estrus; however, an association of age at first estrus with discrete measures of body fatness remains controversial. We tested the hypothesis...

First live offspring born in superovulated sika deer (Cervus nippon) after embryo vitrification.

PubMed

Wang, L; Zhou, G B; Shi, W Q; Shi, J M; Tian, X Z; Gao, C; Zhang, L; Zhu, S E; Zhang, T T; Zeng, S M; Liu, G S

2012-10-15

The rapid growth in sika deer (Cervus nippon) farming and interest in their conservation is an impetus for development of embryo transfer (ET) procedures. However, a paucity of research has prevented widespread application of ET in this species. The objective of the present study was to establish a multiple ovulation and ET procedure with both fresh and vitrified embryos in sika deer. Multiparous weaned hinds (N = 18) were used as embryo donors during the reproductive season of 2008 at a local breeding farm in China. Estrus was synchronized in donors and recipients (N = 38) by inserting a controlled internal drug release for 12 days (insertion = Day 0). Superovulation was induced with a total of 320 mg of NIH-FSH-P1 (Folltropin-V; Bioniche, Belleville, ON, Canada) given as 40 mg im every 12 h from the afternoon of Day 9 to the morning of Day 13. After estrus was detected, donors were artificially inseminated using a transcervical technique. The embryo recovery rate was 76.8% (63/82), including 1.6% (1/63), 77.8% (49/63), and 1.6% (1/63) blastocysts, morula, and eight-cell embryos, respectively. After transfer of fresh and vitrified embryos, pregnancy rates were 85.7% and 61.6% and birth rates were 64.3% and 53.9% (P > 0.05). In conclusion, we developed a satisfactory multiple ovulation and ET procedure in farmed sika deer using vitrified embryos. Copyright © 2012 Elsevier Inc. All rights reserved.

Estrus- and steroid-induced changes in circadian rhythms in a diurnal rodent, Octodon degus.

PubMed

Labyak, S E; Lee, T M

1995-09-01

Diurnal Octodon degus exhibited marked alterations in activity and temperature in conjunction with the 3 wk estrous cycle when housed in LD12:12 light cycle. On the day of estrus, mean daily activity increases 109%, mean core temperature rises .4 degree C, activity onset is advanced 2 h, and amplitudes of both rhythms decline compared with the 3 days prior to estrus. On the day following estrus, activity onset was delayed 4.9 h, and mean activity and core temperature fell below that of the preestrus period. Ovariectomy significantly reduced mean temperature (.98 degree C) but did not significantly alter mean activity, and eliminated cyclic effects of estrus. Estrogen replacement led to a nonsignificant elevation in mean activity and core temperature with no change in the phase angle of entrainment. Progesterone replacement significantly reduced mean core temperature and mean activity, while only the phase angle difference between temperature minimum and activity onset was significantly altered. Intact degus maintained in constant darkness displayed only transient fluctuations in activity onset and temperature minimum during and after estrus. Estrogen or progesterone treatment of ovariectomized, free-running degus altered mean temperature and activity levels, but did not influence tau. Changes in phase angle of entrainment during estrus are not the result of hormone effects on the circadian clock but likely reflect increased or decreased levels of activity.

Short communication: Ability of dogs to detect cows in estrus from sniffing saliva samples.

PubMed

Fischer-Tenhagen, C; Tenhagen, B-A; Heuwieser, W

2013-02-01

Efficient estrus detection in high-producing dairy cows is a permanent challenge for successful reproductive performance. In former studies, dogs have been trained to identify estrus-specific odor in vaginal fluid, milk, urine, and blood samples under laboratory conditions with an accuracy of more than 80%. For on-farm utilization of estrus-detection dogs it would be beneficial in terms of hygiene and safety if dogs could identify cows from the feed alley. The objective of this proof of concept study was to test if dogs can be trained to detect estrus-specific scent in saliva of cows. Saliva samples were collected from cows in estrus and diestrus. Thirteen dogs of various breeds and both sexes were trained in this study. Five dogs had no experience in scent detection, whereas 8 dogs had been formerly trained for detection of narcotics or cancer. In the training and test situation, dogs had to detect 1 positive out of 4 samples. Dog training was based on positive reinforcement and dogs were rewarded with a clicker and food for indicating saliva samples of cows in estrus. A false indication was ignored and documented in the test situation. Dogs with and without prior training were trained for 1 and 5 d, respectively. For determining the accuracy of detection, the position of the positive sample was unknown to the dog handler, to avoid hidden cues to the dog. The overall percentage of correct positive indications was 57.6% (175/304), with a range from 40 (1 dog) to 75% (3 dogs). To our knowledge, this is the first indication that dogs are able to detect estrus-specific scent in saliva of cows. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Suppression of estrus in cats with melatonin implants.

PubMed

Gimenez, F; Stornelli, M C; Tittarelli, C M; Savignone, C A; Dorna, I V; de la Sota, R L; Stornelli, M A

2009-09-01

The objective of this study was to assess the efficacy of a subcutaneous melatonin implant to suppress estrus in queens (felis catus). The hypothesis was that this implant would temporarily and reversibly suppress estrus in queens without producing any clinically detectable side effects. Fourteen adult queens were maintained in cages under artificial illumination (14h light:10h dark) for 45 d and then randomly assigned to one of two treatments. At interestrus, queens received a single subcutaneous melatonin implant (18mg; Melovine [CEVA Sante Animal, Libourne, France]; MEL: n=9), or a single subcutaneous placebo implant without melatonin (0mg; PLA; n=5). At the next estrus, all queens received a second MEL (n=9) or PLA (n=5) implant. Blood samples were taken when queens displayed estrous signs and during interestrus to measure estradiol (E(2)) and progesterone (P(4)), respectively, by radioimmunoassay. There were no significant differences in duration of the interestrus interval in PLA cats, regardless of whether the implants were placed during interestrus or estrus (6.0+/-9.7 d vs. 6.0+/-9.7 d, respectively; least square means [LSM]+/-SEM). However, when MEL implants were placed during interestrus, the duration of interestrus was approximately twice as long as that occurring when MEL implants were placed during estrus (113.3+/-6.1 d vs. 61.1+/-6.8 d, respectively; P<0.01). Serum E(2) and P(4) concentrations were similar in queens with PLA and MEL implants and in queens that received implants in estrus and interestrus. In conclusion, a subcutaneous MEL implant effectively and reversibly suppressed estrus in queens for approximately 2 to 4 mo with no clinically detectable side effects.

Estrogen Contributes to Gender Differences in Mouse Ventricular Repolarization

PubMed Central

Saito, Tomoaki; Ciobotaru, Andrea; Bopassa, Jean Chrisostome; Toro, Ligia; Stefani, Enrico; Eghbali, Mansoureh

2010-01-01

Rationale Fast-transient outward K+ (Ito,f) and ultra-rapid delayed rectifier K+ currents (IKur or IK,slow) contribute to mouse cardiac repolarization. Gender studies on these currents have reported conflicting results. Objective One key missing piece information in these studies is the animals’ estral stage. We decided to revisit gender-related differences in K+ currents, taking into consideration the females’ estral stage. Methods and Results We hypothesized that changes in estrogen levels during the estral cycle could play a role in determining the densities of K+ currents underlying ventricular repolarization. Peak total K+ current (IK,total) densities (pA/pF, at +40 mV) were much higher in males (48.6±3.0) than in females at estrus (27.2±2.3) but not at diestrus-2 (39.1±3.4). Underlying this change, Ito,f and IK,slow were lower in females at estrus vs males and diestrus-2 (IK,slow: male 21.9±1.8, estrus 14.6±0.6, diestrus-2 20.3±1.4; Ito,f: male 26.8±1.9, estrus 14.9±1.6, diestrus-2 22.1±2.1). The lower IK,slow in estrus was only due to IK,slow1 reduction without changes of IK,slow2. Estrogen treatment of ovariectomized mice decreased IK,total (46.4±3.0 to 28.4±1.6), Ito,f (26.6±1.6 to 12.8±1.0) and IK,slow (22.2±1.6 to 17.2±1.4). Transcript levels of Kv4.3 and Kv1.5 (underlying Ito,f and IK,slow, respectively) were lower in estrus vs. diestrus-2 and male. In ovariectomized mice, estrogen treatment resulted in downregulation of Kv4.3 and Kv1.5, but not Kv4.2, KChIP2 and Kv2.1 transcripts. K+ current reduction in high estrogenic conditions were associated with prolongation of the action potential duration and corrected QT interval. Conclusion Downregulation of Kv4.3 and Kv1.5 transcripts by estrogen are one mechanism defining gender-related differences in mouse ventricular repolarization. PMID:19608983

Financial comparison of three testing strategies for detection of estrus in dairy cattle.

PubMed

Mohammed, H O; Loefler, S; Shearer, J

1990-03-15

Three commercial tests that measure progesterone content in milk were evaluated for accuracy of estrus detection. The tests were evaluated on 96 milk samples collected from Holstein cows at a commercial dairy farm in central Florida. The test results were compared with the results of radioimmunoassay on the same sample. Comparisons were made by calculating the sensitivities, specificities, and predictive values. The significance of the statistical association between the tests and the radioimmunoassay was evaluated by use of the McNemar chi 2 test. Decision-tree analysis was used to determine the most useful testing strategy, considering both cost and accuracy. The cowside progesterone assay on estrus-mount detector-positive cows was more profitable than use of estrus-mount patches alone. The return on investment was higher with the cowside test, making it preferred as a field test for detecting estrus.

Delay of constant light-induced persistent vaginal estrus by 24-hour time cues in rats.

PubMed

Weber, A L; Adler, N T

1979-04-20

The normal ovarian cycle of female rats is typically replaced by persistent estrus when these animals are housed under constant light. Evidence presented here shows that the maintenance of periodicity in the environment can at least delay (if not prevent) the photic induction of persistent vaginal estrus. Female rats in constant light were exposed to vaginal smearing at random times or at the same time every day. In another experiment, female rats were exposed to either constant bright light, constant dim light, or a 24-hour photic cycle of bright and dim light. The onset of persistent vaginal estrus was delayed in rats exposed to 24-hour time cues even though the light intensities were the same as or greater than those for the aperiodic control groups. The results suggest that the absence of 24-hour time cues in constant light contributes to the induction of persistent estrus.

A Randomized Clinical Trial of the Effect of the Time of Administration of Cloprostenol on Detention of Estrus in Dairy Cattle

PubMed Central

Hodges, Richard J.; White, Maurice E.; Guard, Charles L.; Powers, Pamela M.; Dinsmore, R. Page; Kelton, David F.; Stehman, Susan M.; Hillman, Robert B.; Yoder, Samuel S.

1988-01-01

We performed a clinical trial to study whether cows with palpable corpora lutea treated with cloprostenol by the farmer on the morning following examination (median time 0630 hours) were seen in heat and conceived more frequently than cows treated by the veterinarian immediately following the reproductive examination (median time 1210 hours). There were no significant differences between the two groups in the proportions of cows seen in estrus or fertility at the induced estrus. The proportions of animals that had the time of onset of estrus recorded and were seen in estrus during working hours (0800-1600 hours) were also not significantly different between the veterinary-treated and farmer-treated groups. Under the conditions of this study, there was no reason to prefer prescribing early morning administration of cloprostenol by farmers over immediate administration of the drug by the clinician. PMID:17423022

Progestin Concentrations Are Increased following Paced Mating in Midbrain, Hippocampus, Diencephalon, and Cortex of Rats in Behavioral Estrus, but Only in Midbrain of Diestrous Rats

PubMed Central

Frye, Cheryl A.; Rhodes, Madeline E.

2013-01-01

Background The progesterone (P4 ) metabolite, 5α-pregnan-3α-ol-20-one (3α,5α-THP), acts in the midbrain ventral tegmental area (VTA) to modulate the intensity and duration of lordosis. 3α,5α-THP can also have anti-anxiety and anti-stress effects in part through actions in the hippocampus. Separate reports indicate that manipulating 3α,5α-THP levels in the VTA or hippocampus respectively can influence lordosis and affective behavior. 3α,5α-THP levels can also be altered by behavioral experiences, such as mating or swim stress. Whether endogenous levels of 3α,5α-THP modulate and/or are increased in response to affective and/or reproductively-relevant behaviors was investigated. Methods In Experiment 1, rats in behavioral estrus or diestrus were individually tested sequentially in the open field, elevated plus maze, partner preference, social interaction, and paced mating tasks and levels of 17 β-estradiol (E2), P4, dihydroprogesterone (DHP), and 3α,5α-THP in serum, midbrain, hippocampus, diencephalon, and cortex were examined. In Experiments 2 and 3, rats in behavioral estrus or diestrus, were individually tested in the battery indicated above, with, or without, paced mating and tissues were collected immediately after testing for later assessment of endocrine measures. Results In Experiment 1, behavioral estrous, compared to diestrous, rats demonstrated more exploratory, anti-anxiety, social, and reproductive behaviors, and had higher levels of E2 and progestins in serum, midbrain, hippocampus, diencephalon, and cortex. In Experiment 2, in midbrain and hippocampus, levels of 3α,5α-THP and its precursor DHP were increased among rats in behavioral estrus that were mated. In diencephalon, and cortex, DHP levels were increased by mating. In Experiment 3, in midbrain, levels of 3α,5α-THP and its precursor DHP were increased among diestrous rats that were tested in the behavioral battery with mating as compared to those tested in the behavioral battery without mating. Conclusions Increased levels of 3α,5α-THP in behavioral estrus versus diestrous rats are associated with enhanced exploratory, anti-anxiety, social, and reproductive behaviors. Rats in behavioral estrus that are mated have further increases in 3α,5α-THP and/or DHP levels in midbrain, hippocampus, diencephalon, and cortex than do non-mated rats in behavioral estrus, whereas diestrous rats only show 3α,5α-THP increases in midbrain in response to behavioral testing that included mating. PMID:17028418

Relationship of follicle size and concentrations of estradiol among cows that do and do not exhibit estrus during a fixed-time AI protocol

USDA-ARS?s Scientific Manuscript database

Cows that exhibited estrus around the time of fixed-time AI had greater pregnancy success compared to cows that did not. The objective of this study was to determine the relationship between follicle size and peak estradiol concentration between cows that did or did not exhibit estrus during a fixed...

EFFECTS OF X-IRRADIATION OF OVARIAN OVA ON THE MORPHOLOGY OF FERTILIZED OVA AND DEVELOPMENT OF EMBRYOS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harvey, E.B.; Chang, M.C.

The time relation between onset of estrus and meiotic division stages in the golden hamster was determined. The morphology of meiotic division stages of the ova are briefly described; neither was observably altered by 200 r x irradiation. Females irradiated at 3 hr before onset of estrus, at onset, and at 5 and 8 hr after onset of estrus had a high percentage of cleaved ova with micronuclei in one of the two blastomeres and a high percentage of de generations of embryos before implantation. However, when irradiated 9 hr before onset of estrus no cleaved ova had micronuclei, andmore » degeneration of embryos was not significantly different from controls. Ovarian ova in meiotic divisioms were not more radiosensitive than ova in diplotene of prophase I (3 hr before onset of estrus), but diplotene ova between 81 and 9 hr before onset of estrus were relatively radioresistant. Ten fetuses of 657 observed were abnormal. However, the weights of the fetuses from irradiated females did not differ significantIy from the non-irradiated control fetuses. It was concluded that the percentage of gross abnormalities and weights of fetuses were not significantly altered by 200 r x irradiation of ovarian ova. (P.C.H.)« less

Delay of behavioral estrus in hamsters and phenobarbital.

PubMed

Alleva, J J

1989-01-01

The onset of behavioral estrus was used as a phase marker of the hamster timing system in SLD 16:8 (dark 20:00-04:00). TZ was injected between 11:00 of cycle day 3 and noon of cycle day 4 when onset of estrus was determined. At no time did injection of TZ cause a phase advance in SLD 16:8. Small delays of estrus resulted from 11:00-16:00 injections but marked delays began with the 17:00 injection. Phenobarbital was injected between noon and 19:30 on cycle day 3. Injections between noon and 16:00 had no effect but all later injections beginning at 17:00 delayed estrus, the 17:30 injection causing the greatest delay. Diazepam also markedly delayed estrus when tested at 17:30. These results with three drugs support results with light pulses that 18:00 in SLD 16:8 marks the same phase of the 24-h hamster timing system as the onset of wheel running does in DD, LL, and WLD. These findings with three GABA potentiators extend to SLD previous evidence based on the onset of wheel running in DD, LL and WLD that GABA may be involved in hamster timekeeping and its responses to light and drugs.

Female Fear: Influence of Estrus Cycle on Behavioral Response and Neuronal Activation

PubMed Central

Chen, Wei; Shields, Jessica; Huang, Wei; King, Jean A

2009-01-01

Our observation that male rats innate fear response differed with hormonal status, as well as the higher prevalence of fear and anxiety disorders in human females led to the current investigation of the impact of phases of the estrous cycle on innate fear responding. Female rats in different phases of the cycle were exposed to an innate fear-inducing stimulus (2,5-dihydro- 2,4,5-trimethylthiazoline, TMT odor) and monitored for changes in behavior and brain activation. Behavioral data showed freezing responses to TMT were significantly enhanced during estrus as compared to other phases of the cycle. This data was supported by significant increases in pixel intensity in cortical and sub-cortical regions in estrus compared to proestrus and diestrus. Imaging results demonstrated significant increases in brain activation in the somatosensory and insular cortices when comparing estrus to diestrus. There were significant increases in neural activity in the BNST and septum in estrus as compared to proestrus. Additionally, the hippocampus, hypothalamus, olfactory system, and cingulate cortex show significant increases in the estrus phase when compared to both diestrus and proestrus. Taken together, these results suggest that the female's hormonal status may be correlated with alterations in both neuronal and behavioral indices of fear. PMID:19428610

Variations in the vulvar temperature of sows during proestrus and estrus as determined by infrared thermography and its relation to ovulation.

PubMed

Simões, Vasco G; Lyazrhi, Faouzi; Picard-Hagen, Nicole; Gayrard, Véronique; Martineau, Guy-Pierre; Waret-Szkuta, Agnès

2014-11-01

The prediction of ovulation time is one of the most important and yet difficult processes in pig production, and it has a considerable impact on the fertility of the herd and litter size. The objective of this study was to assess the vulvar skin temperature of sows during proestrus and estrus using infrared thermography and to establish a possible relationship between the variations in vulvar temperature and ovulation. The experimental group comprised 36 crossbred Large White × Landrace females, of which 6 were gilts and 30 were multiparous sows. Estrus was detected twice daily and the temperature was obtained every 6 hours from the vulvar area and from two control points in the gluteal area (Gluteal skin temperature [GST]). A third variable, vulvar-gluteal temperature (VGT) was obtained from the difference between the vulvar skin temperature and the GST values. The animals were divided into two subgroups: group A consisting of 11 animals with estrus detected at 6:00 AM, Day 4 postweaning, and group B comprising seven animals with estrus detected at 6:00 AM, Day 5 post-weaning. Both groups showed a similar trend in the VGT. The VGT increased during the proestrus, reaching a peak 24 hours before estrus in group A and 48 hours before estrus in group B. The VGT then decreased markedly reaching the lowest value in groups A and B, respectively, 12 and 6 hours after estrus. Although the time of ovulation was only estimated on the basis of a literature review, the matching between the temporal variations of the VGT values and the predicted time of the peak of estradiol secretion that ultimately leads to the ovulation processes suggests that the VGT values represent a potential predictive marker of the ovulatory events. Copyright © 2014 Elsevier Inc. All rights reserved.

Feasibility of transabdominal Doppler sonography for studying uterine blood flow characteristics in cycling gilts.

PubMed

Herlta, Catherine; Starka, Rosa; Sigmarsson, Haukur L; Kauffold, Johannes

2018-06-01

To test for the feasibility of transabdominal Doppler sonography (color, power, pulse wave) to define uterine perfusion characteristics throughout the estrous cycle in gilts. A total of 15 gilts were synchronized for estrus and scanned in their following spontaneous cycle while being restrained in a purpose-designed mobile crate. To define uterine perfusion characteristics, vessels in between and within uterine cross-sections were imaged and recorded as video sequences to be analyzed by PixelFlux® software for perfused area (Amix), blood flow velocity (vmix) and intensity (Imix) as well as resistance (RIvmix) and pulsatility index (PIvmix). Color Doppler sonography proved to be the only feasible technique, as it was less affected by animal movements than power and pulse wave sonography. As determined by color Doppler sonography, all five parameters determined showed specific patterns through the estrous cycle, i. e. Amix, vmix, Imix were high in proestrus, decreased in estrus and remained low in midestrus and most parts of diestrus; RIvmix and PIvmix with inversely paralleled patterns. This study has demonstrated that transabdominal color Doppler but not power and pulse wave Doppler sonography is feasible to be performed in crate-restrained gilts for studying uterine perfusion characteristics during the estrous cycle, and that changes of uterine perfusion over the course of the estrous cycle can be clearly followed by color Doppler sonography. Results encourage the use of color Doppler sonography for studying i. e. uterine capacity or uterus related infertility such as for cases of clinically unapparent endometritis. Schattauer GmbH.

In Utero Domoic Acid Toxicity: A Fetal Basis to Adult Disease in the California Sea Lion (Zalophus californianus)

PubMed Central

Ramsdell, John S.; Zabka, Tanja S.

2008-01-01

California sea lions have been a repeated subject of investigation for early life toxicity, which has been documented to occur with increasing frequency from late February through mid-May in association with organochlorine (PCB and DDT) poisoning and infectious disease in the 1970’s and domoic acid poisoning in the last decade. The mass early life mortality events result from the concentrated breeding grounds and synchronization of reproduction over a 28 day post partum estrus cycle and 11 month in utero phase. This physiological synchronization is triggered by a decreasing photoperiod of 11.48 h/day that occurs approximately 90 days after conception at the major California breeding grounds. The photoperiod trigger activates implantation of embryos to proceed with development for the next 242 days until birth. Embryonic diapause is a selectable trait thought to optimize timing for food utilization and male migratory patterns; yet from the toxicological perspective presented here also serves to synchronize developmental toxicity of pulsed environmental events such as domoic acid poisoning. Research studies in laboratory animals have defined age-dependent neurotoxic effects during development and windows of susceptibility to domoic acid exposure. This review will evaluate experimental domoic acid neurotoxicity in developing rodents and, aided by comparative allometric projections, will analyze potential prenatal toxicity and exposure susceptibility in the California sea lion. This analysis should provide a useful tool to forecast fetal toxicity and understand the impact of fetal toxicity on adult disease of the California sea lion. PMID:18728728

Development of starch based mucoadhesive vaginal drug delivery systems for application in veterinary medicine.

PubMed

Gök, Mehmet Koray; Özgümüş, Saadet; Demir, Kamber; Cirit, Ümüt; Pabuccuoğlu, Serhat; Cevher, Erdal; Özsoy, Yıldız; Bacınoğlu, Süleyman

2016-01-20

The aim of this study was to prepare and evaluate the mucoadhesive, biocompatible and biodegradable progesterone containing vaginal tablets based on modified starch copolymers for the estrus synchronization of ewes. Starch-graft-poly(acrylic acid) copolymers (S-g-PAA) were synthesized and characterized. The vaginal tablets were fabricated with S-g-PAA and their equilibrium swelling degree (Qe) and matrix erosion (ME%) were determined in lactate buffer solution. In vitro, mucoadhesive properties of the tablets were investigated by using ewe vaginal mucosa and in vivo residence time were also investigated. In vitro and in vivo progesterone release profiles from the tablets were compared with two commercial products. Tablet formulation containing wheat starch based grafted copolymer (WS-g-PAA)gc indicated promising results and might be convenient as an alternative product to the commercial products in veterinary medicine. Copyright © 2015 Elsevier Ltd. All rights reserved.

[Recovery and light microscopic evaluation of follicular oocytes of swine and relationship between the degeneration rate of oocytes and the estrus phase].

PubMed

Schnurrbusch, U; Schmette, C; Elze, K

1990-10-01

Cumulus-oocyte complexes were recovered from 25 gilts by aspiration of follicular fluid or cutting of follicles from all Graafian follicles of greater than or equal to 3 mm in diameter during diestrus, proestrus or estrus. In 5 gilts the oocytes were collected post ovulation by flushing of oviducts. The recovery rate of follicular oocytes differed between 75.5% during the late diestrus (days 13-17) and 43.5% during the proestrus (days 18-21). During the proestrus and on day 1 of the estrus the recovery of oocytes was more difficult as a result of the higher viscosity of follicular fluid and the mucification of cumulus-oocyte complexes. The degeneration rate of oocytes was high during the diestrus with a peak at the time of regression of corpora lutea. From diestrus to the estrus the degeneration rate decreased. Following degeneration rates were found in the oocytes during the cycle: days 7-12: 38.8%, days 13-17: 50.0%, days 18-21: 29.6%, day 1 of the estrus: 10.8%, day 2 of the estrus ante ovulation: 11.8%, day 2 of the estrus post ovulation: 6.2%. Signs of degeneration were: Loss of cumulus cells (during diestrus and proestrus), damaged zona pellucida, enlargement of perivitelline space, deformation of oocyte, alteration of structure of the ooplasm, diameter of vitellus less than 100 microns. It was concluded that the selection of dominant follicles takes place in pigs during a long time of the cycle, especially during the diestrus. There were not any indications of a 2-wave hypothesis of follicular growth during the cycle in pig.

Whole-body metabolism varies across the estrous cycle in Sprague-Dawley rats.

PubMed

Parker, G C; McKee, M E; Bishop, C; Coscina, D V

2001-10-01

Food intake in rats and other mammals is lowest at estrus and highest at diestrus. While much is known about the effects of different estrous phases on energy intake, as well as some of the metabolic effects the associated hormones exert, little has been reported about changes in whole-body metabolism that accompany those phases. This study investigates how energy expenditure (EE) and respiratory quotient (RQ) vary in intact female Sprague-Dawley rats (n=12) tested mid-light cycle over 2 h on days associated with estrus vs. diestrus. Rats showed small but reliable decreases in body weight on days associated with estrus, but not diestrus. EE was significantly increased by approximately 21% on the day associated with estrus compared to diestrus. At the same time, RQ was significantly decreased by approximately 7% on the day associated with estrus, indicating a relative shift to fat over carbohydrate as the energy substrate to support energetic needs. Future investigations of ingestive processes can integrate the present findings to investigate how gender differences in feeding and metabolism contribute to regulatory behaviors.

An ex ante analysis on the use of activity meters for automated estrus detection: to invest or not to invest?

PubMed

Rutten, C J; Steeneveld, W; Inchaisri, C; Hogeveen, H

2014-11-01

The technical performance of activity meters for automated detection of estrus in dairy farming has been studied, and such meters are already used in practice. However, information on the economic consequences of using activity meters is lacking. The current study analyzes the economic benefits of a sensor system for detection of estrus and appraises the feasibility of an investment in such a system. A stochastic dynamic simulation model was used to simulate reproductive performance of a dairy herd. The number of cow places in this herd was fixed at 130. The model started with 130 randomly drawn cows (in a Monte Carlo process) and simulated calvings and replacement of these cows in subsequent years. Default herd characteristics were a conception rate of 50%, an 8-wk dry-off period, and an average milk production level of 8,310 kg per cow per 305 d. Model inputs were derived from real farm data and expertise. For the analysis, visual detection by the farmer ("without" situation) was compared with automated detection with activity meters ("with" situation). For visual estrus detection, an estrus detection rate of 50% and a specificity of 100% were assumed. For automated estrus detection, an estrus detection rate of 80% and a specificity of 95% were assumed. The results of the cow simulation model were used to estimate the difference between the annual net cash flows in the "with" and "without" situations (marginal financial effect) and the internal rate of return (IRR) as profitability indicators. The use of activity meters led to improved estrus detection and, therefore, to a decrease in the average calving interval and subsequent increase in annual milk production. For visual estrus detection, the average calving interval was 419 d and average annual milk production was 1,032,278 kg. For activity meters, the average calving interval was 403 d and the average annual milk production was 1,043,398 kg. It was estimated that the initial investment in activity meters would cost €17,728 for a herd of 130 cows, with an additional cost of €90 per year for the replacement of malfunctioning activity meters. Changes in annual net cash flows arising from using an activity meter included extra revenues from increased milk production and number of calves sold, increased costs from more inseminations, calvings, and feed consumption, and reduced costs from fewer culled cows and less labor for estrus detection. These changes in cash flows were caused mainly by changes in the technical results of the simulated dairy herds, which arose from differences in the estrus detection rate and specificity between the "with" and "without" situations. The average marginal financial effect in the "with" and "without" situations was €2,827 for the baseline scenario, with an average IRR of 11%. The IRR is a measure of the return on invested capital. Investment in activity meters was generally profitable. The most influential assumptions on the profitability of this investment were the assumed culling rules and the increase in sensitivity of estrus detection between the "without" and the "with" situation. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Integrating an automated activity monitor into an artificial insemination program and the associated risk factors affecting reproductive performance of dairy cows.

PubMed

Burnett, Tracy A; Madureira, Augusto M L; Silper, Bruna F; Fernandes, A C C; Cerri, Ronaldo L A

2017-06-01

The aim of this study was to compare 2 reproductive programs for the management of first postpartum artificial insemination (AI) based on activity monitors and timed AI, as well as to determine the effect of health-related factors on detection and expression of estrus. Lactating Holstein cows (n = 918) from 2 commercial farms were enrolled. Estrous cycles of all cows were presynchronized with 2 injections of PGF 2α administered 2 wk apart. Treatments were (1) first insemination performed by timed AI (TAI) and (2) first insemination based upon the detection of estrus by activity monitors (ACT; Heatime, SCR Engineering, Netanya, Israel) after the presynchronization, whereas cows not inseminated by the detection of estrus were enrolled in the Ovsynch protocol. Body condition score (BCS; scale 1 to 5), hock score (scale: 1 to 4), gait score (scale: 1 to 4), and corpus luteum presence detected by ovarian ultrasonography were recorded twice during the presynchronization. On the ACT treatment, 50.5% of cows were inseminated based on detected estrus, whereas 83.2% of the cows on the TAI treatment were inseminated appropriately after the timed AI protocol. Pregnancy per AI did not differ by treatment (30.8 vs. 33.5% for ACT and TAI, respectively). Success of pregnancy was affected by parity, cyclicity, BCS, milk production, and a tendency for leg health. In addition, treatment × cyclicity and treatment × parity interactions were found to affect pregnancy success, where anovulatory cows and older cows had compromised pregnancy outcomes on the ACT treatment but not on the TAI treatment. Factors affecting pregnancy outcomes varied among farms. Hazard of pregnancy by 300 DIM was affected by farm, parity, BCS, a treatment × cyclicity interaction, and a tendency for an interaction between leg health and farm. Detection of estrus was affected by farm, parity, cyclicity, and leg health, but not BCS or milk production. Expression of estrus was compromised in anovular and older cows, and by the timing of the estrus event, but not by gait score, BCS, or milk production. Increased duration of estrus, but not intensity of estrus, improved pregnancy per AI. In conclusion, using an automated activity monitor for the detection of estrus within a Presynch-Ovsynch program resulted in similar pregnancy per AI and days open compared with a reproduction program that was strictly based on timed AI for first postpartum AI. In contrast, notable variations in reproductive outcomes were detected between farms, suggesting that the use of automated activity monitors is prone to individual farm management. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Progesterone-releasing devices for cattle estrus induction and synchronization: Device optimization to anticipate shorter treatment durations and new device developments.

PubMed

de Graaff, W; Grimard, B

2018-05-01

Synchronization programs using progesterone-releasing intravaginal devices that allow for fixed time artificial insemination are still finding increasing application in bovine reproduction. This practice is useful for rationalizing livestock management because an increased number of cows can be inseminated in one session without the need for estrus detection. Although much of the innovation related to the design and development of intravaginal devices for use in cattle took place in the previous century, progress in understanding the physiology of the bovine estrous cycle resulted in shorter treatment durations, a trend which is still continuing. In this competitive market, with little functional differentiation between the existing devices, the shorter treatment duration prompted for optimization of the progesterone content in the device, as the cost of the drug significantly contributes to the price per unit. For CIDR ® a reduction of the progesterone content of about 30 per cent was realized. Price reduction remained an important target for further device development. Next to reduction of progesterone content, cheaper and easier to process materials like polyethylene vinyl acetate (EVA) copolymers have been explored to replace the commonly used silicone elastomers. The reengineering effort of CIDR ® demonstrated that knowledge of release kinetics and insight into gradual depletion patterns in the device is critical for optimization of drug content without compromising performance (blood levels). More recent publications related to the use of alternative polymers like EVA and polyisoprene (IP) indicated encouraging results regarding further reduction of progesterone content. The use of EVA seems most promising, because it is in principle a low-cost polymer available in many grades and this thermoplastic polymer can be processed easily by means of commonly used techniques like injection molding and extrusion. The use of thermoplastic polymers, however, requires insight into the physical-chemical phenomena related to drug dissolution and re-crystallization taking place in the polymer during processing at high temperatures. These aspects, which may critically affect product stability, are often overlooked and are prompting to cover some of the background in this review. Finally, two different innovative approaches are discussed, one related to programable electronic devices for tailored simultaneous drug release and the other is a flexible drug-loaded helix, which is retained very well in several species without causing the usual inflammatory response. Copyright © 2017 Elsevier Inc. All rights reserved.

Toxoplasma gondii influences aversive behaviors of female rats in an estrus cycle dependent manner.

PubMed

Golcu, Doruk; Gebre, Rahiwa Z; Sapolsky, Robert M

2014-08-01

The protozoan Toxoplasma gondii (T. gondii) manipulates the behavior of its rodent intermediate host to facilitate its passage to its feline definitive host. This is accomplished by a reduction of the aversive response that rodents show towards cat odors, which likely increases the predation risk. Females on average show similar changes as males. However, behaviors that relate to aversion and attraction are usually strongly influenced by the estrus cycle. In this study, we replicated behavioral effects of T. gondii in female rats, as well as expanded it to two novel behavioral paradigms. We also characterized the role of the estrus cycle in the behavioral effects of T. gondii on female rats. Uninfected females preferred to spend more time in proximity to rabbit rather than bobcat urine, and in a dark chamber rather than a lit chamber. Infected females lost both of these preferences, and also spent more time investigating social novelty (foreign bedding in their environment). Taken together, these data suggest that infection makes females less risk averse and more exploratory. Furthermore, this effect was influenced by the estrus cycle. Uninfected rats preferred rabbit urine to bobcat urine throughout the cycle except at estrus and metestrus. In contrast, infected rats lost this preference at every stage of the cycle except estrus. Commensurate with the possibility that this was a hormone-dependent effect, infected rats had elevated levels of circulating progesterone, a known anxiolytic. Copyright © 2014 Elsevier Inc. All rights reserved.

Toxoplasma gondii influences aversive behaviors of female rats in an estrus cycle dependent manner

PubMed Central

Golcu, Doruk; Gebre, Rahiwa Z.; Sapolsky, Robert M.

2016-01-01

The protozoan Toxoplasma gondii (T. gondii) manipulates the behavior of its rodent intermediate host to facilitate its passage to its feline definitive host. This is accomplished by a reduction of the aversive response that rodents show towards cat odors, which likely increases the predation risk. Females on average show similar changes as males. However, behaviors that relate to aversion and attraction are usually strongly influenced by the estrus cycle. In this study, we replicated behavioral effects of T. gondii in female rats, as well as expanded it to two novel behavioral paradigms. We also characterized the role of the estrus cycle in the behavioral effects of T. gondii on female rats. Uninfected females preferred to spend more time in proximity to rabbit rather than bobcat urine, and in a dark chamber rather than a lit chamber. Infected females lost both of these preferences, and also spent more time investigating social novelty (foreign bedding in their environment). Taken together, these data suggest that infection makes females less risk averse and more exploratory. Furthermore, this effect was influenced by the estrus cycle. Uninfected rats preferred rabbit urine to bobcat urine throughout the cycle except at estrus and metestrus. In contrast, infected rats lost this preference at every stage of the cycle except estrus. Commensurate with the possibility that this was a hormone-dependent effect, infected rats had elevated levels of circulating progesterone, a known anxiolytic. PMID:24907696

[The participation of vaginal bacteria in Phodopus campbelli in the chemical communication between male and female].

PubMed

Sokolov, V E; Ushakova, N A; Surov, A V; Telitsyna, A Iu

1994-01-01

Phodopus campbelli commonly occurs in dry steppe and semidesert zone of south Siberia, Mongolia and China. Using radiotelemetry we found that a male has to cover about 2 km from his burrow to encounter a receptive female. Female in estrus marks a small area around its burrow by vaginal smear. Experiments were carried out in laboratory to discover the nature of this strong signal. In a "open field" area four boxes within stimuli we recorded the time complemented spent by males near boxes to study the attractive effect of intact receptive female, germ culture of vaginal smear and artificial mixed culture of bacteria which were found in the vaginal smear of Ph. campbelli receptive female. Males (n = 15) spent significantly more time near the boxes with female in estrus or day before estrus as compared with two other days of cycle. Germ culture from vaginal smear sampled on the estrus day was more attractive to males on 6th day than on the 2, -3, -5, -7, -8--or 9th days of cultivation, pure culture or germ culture sampled on anestrus. Mixed culture, which simulated the proportion of predominant bacteria in the estrus vaginal smear, was significantly more attractive for males on the 3rd day of cultivation. Thus sexual attractant of Ph. campbelli could be produced by some bacteria located in the vagina in estrus and it takes a couple of days of cultivation for maximum attractive effect.

Pregnancy prediction on the day of embryo transfer (Day 7) and Day 14 by measuring luteal blood flow in dairy cows.

PubMed

Kanazawa, Tomomi; Seki, Motohide; Ishiyama, Keiki; Kubo, Tomoaki; Kaneda, Yoshiyuki; Sakaguchi, Minoru; Izaike, Yoshiaki; Takahashi, Toru

2016-10-01

This study aimed to assess the suitability of luteal blood flow analyses measured by color Doppler ultrasonography (CDUS), to predict pregnancy at pre- and post-embryo transfer (ET) in dairy cows, and to compare with the established criterion like luteal size and plasma progesterone (P4) concentrations. Lactating Holstein cows (n = 65) with spontaneous (n = 34) or synchronized estrus (n = 31) were examined. Cows with a CL greater than or equal to 20 mm in diameter (n = 58) received embryo transfer on Day 7 (Day 0 = estrus). Brightness mode images were captured for calculation of the CL area, luteal cavity area, and dominant follicle area on Days 3, 5, 7, and 14. Color Doppler ultrasonography examinations were conducted to determine the blood flow area (BFA) within the CL at the maximum diameter and the time-averaged maximum velocity (TAMV) of the base of the spiral artery on the same days. Plasma P4 concentrations were determined from blood samples collected at each ultrasound examination. Pregnancy was diagnosed by an ultrasound on Day 30. There was no significant difference in the proportion of cows received embryo (91.2% vs. 87.1%, P = 0.70) and pregnancy rate (58.1% vs. 59.3%, P = 1.00) between the spontaneous estrus and synchronized groups. The BFA values of the pregnant group (n = 34) were approximately 1.42 and 1.54 times higher than those of the nonpregnant group (n = 24) on Days 7 (0.54 ± 0.04 cm(2) vs. 0.38 ± 0.02 cm(2); P < 0.01) and 14 (0.80 ± 0.23 cm(2) vs. 0.52 ± 0.22 cm(2); P < 0.01), respectively. The TAMV of the pregnant group was approximately 1.45 times higher than that of the nonpregnant group on Day 14 (57.8 ± 3.5 cm/s vs. 40.0 ± 3.3 cm/s; P < 0.01). However, no differences were found in the CL area, CL tissue area, dominant follicle area, and plasma P4 concentrations among these groups. In addition, the best logistic regression model to predict pregnancy included scores for BFA on Day 7, BFA and TAMV on Day 14. Setting the cutoff value of BFA at 0.43 cm(2) yielded the highest sensitivity (79.4%) and specificity (75.0%) on Day 7, indicating the effectiveness of using BFA data for predicting pregnancy on Day 7. Furthermore, setting the cutoff value at one obtained from a sample with BFA 0.63 cm(2) and TAMV 50.60 cm/s yielded the highest sensitivity (85.3%) and specificity (91.7%) on Day 14. In conclusion, the evaluations of BFA on Day 7, and paired BFA and TAMV on Day 14 represent reliable predictors of pregnancy in the cow. Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of breeding method and season on pregnancy rate and embryonic and fetal losses in lactating Nili-Ravi buffaloes.

PubMed

Qayyum, Arslan; Arshad, Usman; Yousuf, Muhammad Rizwan; Ahmad, Nasim

2018-03-01

The aim of this study was to determine the effect of breeding method and season on pregnancy rate and cumulative embryonic and fetal losses in Nili-Ravi buffalo. Estrus detection was performed twice a day by teaser buffalo bull for 1 hour each. A 2 × 2 factorial design was used to address the breeding method and season. Buffaloes (n = 130) exhibiting estrus were randomly assigned to be bred either in peak breeding season (PBS; n = 80) or low breeding season (LBS; n = 50). Within each season, buffaloes were divided to receive either natural service (NS; n = 65) or artificial insemination (AI; n = 65). NS buffaloes, in estrus, were allowed to remain with the bull until mating. AI was achieved, using frozen thawed semen of bull of known fertility. PBS comprised of September to December and LBS were from May to July. Serial ultrasonography was performed on days 30, 45, 60, and 90 after breeding (day 0) to monitor pregnancy rate and embryonic and fetal losses. The pregnancy rate on day 30 after breeding was higher in NS as compared to AI group (63 vs. 43%; P < 0.05) during PBS while it did not differ (48 vs. 32%; P > 0.05) in LBS. The cumulative embryonic and fetal losses between days 31 and 90 were significantly lower in PBS than LBS (33 vs. 60%; P < 0.05), ignoring breeding method. Pregnancy rates were better with NS in PBS, and cumulative embryonic fetal losses were higher in LBS in Nili-Ravi buffalo.

Influence of growth rate and onset of boar contact on puberty attainment of replacement gilts raised in Thailand.

PubMed

Roongsitthichai, Atthaporn; Olanratmanee, Em-On; Tummaruk, Padet

2014-10-01

This study aimed to investigate the influence of growth rate and onset of boar contact on age at first observed estrus of the replacement gilts raised in Thailand. In total, 766 gilts were measured for body weight and backfat thickness prior to insemination. Body weight was further calculated for growth rate. Estrus detection was performed twice a day by back pressure test with an existence of mature boars with high libido. The first date of boar exposure and that of first observed estrus were individually recorded. Due to growth rate, they were classified into three groups: high (>700 g/day), moderate (600-700 g/day), and low (<600 g/day). According to onset of boar contact, the gilts were grouped into two categories: early (<150 days) and late (≥150 days). The results revealed that the gilts expressed first observed estrus, averagely, at age 205.1 ± 34.1 days, had a growth rate of 615.5 ± 57.6 g/day, and first contact with boars at 160.7 ± 19.9 days of age. The gilts with low growth rate expressed first estrus later than those with moderate (208.6 ± 2.0 vs 198.0 ± 3.2 days, P = 0.033) and high growth rate (208.6 ± 2.0 vs 193.9 ± 6.7 days, P = 0.005) groups. Together with the influence of boar exposure, the gilts contacted boar earlier with high growth rate showed first estrus at age 180.3 ± 10.1 days, whereas those with later boar contact with low growth rate showed first estrus at age 197.9 ± 3.2 days. In summary, the replacement gilts should have high growth rate and contact boar early to attain puberty faster and possess decent subsequent reproductive performance.

Intraocular 6-hydroxydopamine prevents the persistent estrus induced by continuous light.

PubMed

Shimizu, K; Hokano, M

1985-01-15

Following the intraocular injection of 6-hydroxydopamine, which can destroy the retinal dopaminergic neurons, female rats showed a normal estrous cycle in LD 12:12 but not a persistent estrus in continuous light.

Monoamines and sexual function in rats bred for increased catatonic reactivity.

PubMed

Klochkov, D V; Alekhina, T A; Kuznetsova, E G; Barykina, N N

2009-07-01

Body weight, ovary and uterus weight, the nature of estral cycles, and hypothalamus dopamine and noradrenaline levels and plasma testosterone levels were studied in female GC rats, bred for increased catatonic reactivity, at different stages of the estral cycle (estrus, proestrus). The outbred Wistar strain served as controls. On the background of decreased body weight, GC females showed impairments to the morphological cyclical changes in the ovaries and uterus, with a reduction in ovary weight in diestrus (p < 0.01) and a smaller estrogen-dependent increase in uterus weight in estrus as compared with Wistar females. On the background of decreases in dopamine and noradrenaline contents in the hypothalamus, GC rats showed higher levels of these monoamines in estrus and lower levels in diestrus. Plasma testosterone levels in female GC rats were higher in diestrus than in estrus and in Wistar rats.

Neonatal handling and reproductive function in female rats.

PubMed

Gomes, C M; Raineki, C; Ramos de Paula, P; Severino, G S; Helena, C V V; Anselmo-Franci, J A; Franci, C R; Sanvitto, G L; Lucion, A B

2005-02-01

Neonatal handling induces anovulatory estrous cycles and decreases sexual receptivity in female rats. The synchronous secretion of hormones from the gonads (estradiol (E2) and progesterone (P)), pituitary (luteinizing (LH) and follicle-stimulating (FSH) hormones) and hypothalamus (LH-releasing hormone (LHRH)) are essential for the reproductive functions in female rats. The present study aimed to describe the plasma levels of E2 and P throughout the estrous cycle and LH, FSH and prolactin (PRL) in the afternoon of the proestrus, and the LHRH content in the medial preoptic area (MPOA), median eminence (ME) and medial septal area (MSA) in the proestrus, in the neonatal handled rats. Wistar pup rats were handled for 1 min during the first 10 days after delivery (neonatal handled group) or left undisturbed (nonhandled group). When they reached adulthood, blood samples were collected through a jugular cannula and the MPOA, ME and MSA were microdissected. Plasma levels of the hormones and the content of LHRH were determined by RIA. The number of oocytes counted in the morning of the estrus day in the handled rats was significantly lower than in the nonhandled ones. Neonatal handling reduces E2 levels only on the proestrus day while P levels decreased in metestrus and estrus. Handled females also showed reduced plasma levels of LH, FSH and PRL in the afternoon of the proestrus. The LHRH content in the MPOA was significantly higher than in the nonhandled group. The reduced secretion of E2, LH, FSH and LHRH on the proestrus day may explain the anovulatory estrous cycle in neonatal handled rats. The reduced secretion of PRL in the proestrus may be related to the decreased sexual receptiveness in handled females. In conclusion, early-life environmental stimulation can induce long-lasting effects on the hypothalamus-pituitary-gonad axis.

Failure to establish and maintain a pregnancy in undernourished recipient ewes is associated with a poor endocrine milieu in the early luteal phase.

PubMed

de Brun, Victoria; Meikle, Ana; Fernández-Foren, Andrea; Forcada, Fernando; Palacín, Inmaculada; Menchaca, Alejo; Sosa, Cecilia; Abecia, José-Alfonso

2016-10-01

Embryos from undernourished and control donor ewes were transferred to undernourished and control recipient ewes. Progesterone and metabolic hormones were investigated in recipient ewes to determine their association with pregnancy success. Forty-five donor and 52 recipient Rasa Aragonesa ewes were fed 1.5 (control group; donor n=20; recipient n=25) or 0.5 (low group; donor n=25; recipient n=27) times the daily requirements for maintenance from the onset of estrous synchronization treatment to embryo collection and transfer. The embryos were collected 7days after the onset of estrus (day 0), and two good-quality embryos were transferred into each recipient ewe. The percentage of pregnant ewes on day 18 and 40 did not differ between the two groups, although the recipient undernourished ewes tended to have greater late embryonic mortality (from days 18-40) than the control recipient ewes (P=0.11). No effect of the nutrition of the donor was found. Recipients that became pregnant had a higher ovulation rate than non-pregnant ewes (P=0.02). Undernourished ewes had lower plasma insulin concentrations than control ewes (P=0.03), and those that suffered late embryo mortality (from days 18-40) tended to have lower insulin and progesterone concentrations than their counterparts that remained pregnant (P=0.06 and P=0.07, respectively). In this study, pregnancy in control and undernourished recipient ewes was not associated with the origin of the embryo (undernourished and control donors). In conclusion, failure to establish and maintain a pregnancy was associated with lower progesterone and insulin levels one week after estrus in recipient ewes. Copyright © 2016 Elsevier B.V. All rights reserved.

Management considerations in heifer development and puberty.

PubMed

Patterson, D J; Perry, R C; Kiracofe, G H; Bellows, R A; Staigmiller, R B; Corah, L R

1992-12-01

Management of replacement beef heifers should focus on factors that enhance physiological processes that promote puberty. Age at puberty is important as a production trait when heifers are bred to calve as 2-yr-olds and in systems that impose restricted breeding periods. Calving by 24 mo of age is necessary to obtain maximum lifetime productivity. Because the reproductive system is the last major organ system to mature, factors that influence puberty are critical. The influence of environment on the sequence of events leading to puberty in the heifer is dictated largely by the nutritional status of the animal and related effects on growth rate and development. Management strategies have been designed to ensure that heifers reach a prebreeding target weight that supports optimum reproductive performance, and consequences of inadequate or excessive development have been evaluated. Those strategies are based on evidence linking postweaning nutritional development with key reproductive events that include age at puberty and first breeding, conception, pregnancy loss, incidence and severity of dystocia, and postpartum interval to estrus. Management alternatives that ultimately affect lifetime productivity and reproductive performance of heifers begin at birth and include decisions that involve growth-promoting implants, creep-feeding, breed type and(or) species, birth date and weaning weight, social interaction, sire selection, and exogenous hormonal treatments to synchronize or induce estrus. Basic and applied future research efforts should converge to match in a realistic manner the production potential of the animal with available resources. Strategies that incorporate consideration of nutrition, genetics, and emerging management techniques will need to be tested to enable producers to make decisions that result in profit. This review evaluates the current status of knowledge relating to management of the replacement beef heifer and serves to stimulate research needed to enhance management techniques to ensure puberty at an optimal age.

Effects of creep feeding and monensin on reproductive performance and lactation of beef heifers.

PubMed

Hixon, D L; Fahey, G C; Kesler, D J; Neumann, A L

1982-09-01

A 23 factorial arrangement of treatments was utilized to determine the effect of breed, creep feeding and monensin on subsequent reproductive performance and lactation of 32 primiparous heifers. One-half of each breed (Angus and Hereford) group had access to creep feed (2.67 Mcal metabolizable energy/kg) while nursing their dams. Approximately 40 d before breeding through 120 d of lactation, all heifers were fed a suboptimal energy diet and 50% of each breed and creep group received 200 mg monensin/head daily. Estrus was synchronized with a progestogen. Volatile fatty acids (VFA) were determined periodically throughout the monensin-feeding portion of the experiment. Twenty-four hour milk production, percentage butterfat and percentage solids-not-fat were determined at 60 and 120 d postpartum. Weaning weights (adjusted to 205 d and for age of dam) of the original heifers were heavier (P less than .05) for those that were creep fed compared with those not creep fed (219 vs 202 kg). Monensin-supplemented females gained significantly more weight from the initiation of treatment to immediately postcalving and gave birth to heavier calves (P less than .05) even though they received comparable amounts of dietary energy as those that did not receive monensin. The energy stressed, monensin-supplemented first-calf heifers exhibited a shorter postpartum interval (P less than .05) to first estrus than did those that did not receive monensin (55.7 vs 69.1 d, respectively). First-calf heifers that had been creep fed while nursing their dams had a lower (P less than .05) daily milk yield at 120 d post-partum than those that did not have access to creep feed. No detrimental effects were observed due to long-term monensin supplementation.

Effect of restricted suckling on the onset of follicular dynamics and body condition score in Brahman cattle raised under tropical conditions.

PubMed

Mondragón, Violeta; Galina, Carlos S; Rubio, Ivette; Corro, Manuel; Salmerón, Frida

2016-04-01

With the aim of evaluating the effect of restricted suckling on the onset of follicular dynamics and body condition, multiparous Bos indicus cows were distributed in two groups. One group (RS=36) was subjected to a scheme of restricted suckling starting at 21 days postpartum. Calves were allowed to suckle once per day for a period of two h whilst the control group (C=18) remained with their dams at all times. At calving, body condition score, back fat thickness and body weight had similar values (p>0.05) for both groups. By day 85 postpartum both groups had recorded losses in body weight. The cows in the continuous group formed a greater (p<0.05) number of follicles of class size <6mm in both periods before and after synchronization. The proportion of cows showing estrus and ovulation before 45 days, was not different (p>0.05). The number of cows that exhibited estrus after 45 days, was greater (p<0.05) in RS than C group, 72.2% and 55.5%, respectively. Same situation (p<0.05) occurred in cows that ovulated, 88.8 and 66.7%, for groups RS and C, respectively. The subset in the intensive observations showed that the size of the bigger follicle was larger (p<0.05) for RS cows than C cows from 36 h after CIDR withdrawal. At 57 h, the size of the biggest follicle recorded was not different between groups (p>0.05). A regime of restricted suckling favors the earlier growth of follicles and the prompt restoration of ovarian activity. Copyright © 2016 Elsevier B.V. All rights reserved.

Luteal function during the estrous cycle in arginine-treated ewes fed different planes of nutrition.

PubMed

Bass, Casie S; Redmer, Dale A; Kaminski, Samantha L; Grazul-Bilska, Anna T

2017-03-01

Functions of corpus luteum (CL) are influenced by numerous factors including hormones, growth and angiogenic factors, nutritional plane and dietary supplements such as arginine (Arg), a semi-essential amino acid and precursor for proteins, polyamines and nitric oxide (NO). The aim of this study was to determine if Arg supplementation to ewes fed different planes of nutrition influences: (1) progesterone (P4) concentrations in serum and luteal tissue, (2) luteal vascularity, cell proliferation, endothelial NO synthase (eNOS) and receptor (R) soluble guanylate cyclase β protein and mRNA expression and (3) luteal mRNA expression for selected angiogenic factors during the estrous cycle. Ewes (n = 111) were categorized by weight and randomly assigned to one of three nutritional planes: maintenance control (C), overfed (2× C) and underfed (0.6× C) beginning 60 days prior to onset of estrus. After estrus synchronization, ewes from each nutritional plane were assigned randomly to one of two treatments: Arg or saline. Serum and CL were collected at the early, mid and late luteal phases. The results demonstrated that: (1) nutritional plane affected ovulation rates, luteal vascularity, cell proliferation and NOS3, GUCY1B3, vascular endothelial growth factor (VEGF) and VEGFR2 mRNA expression, (2) Arg affected luteal vascularity, cell proliferation and NOS3, GUCY1B3, VEGF and VEGFR2 mRNA expression and (3) luteal vascularity, cell proliferation and the VEGF and NO systems depend on the stage of the estrous cycle. These data indicate that plane of nutrition and/or Arg supplementation can alter vascularization and expression of selected angiogenic factors in luteal tissue during the estrous cycle in sheep. © 2017 Society for Reproduction and Fertility.

Effect of body condition score of does and use of bucks subjected to added artificial light on estrus response of Alpine goats.

PubMed

Rivas-Muñoz, Raymundo; Carrillo, Evaristo; Rodriguez-Martinez, Rafael; Leyva, Carlos; Mellado, Miguel; Véliz, Francisco Gerardo

2010-08-01

The effects of body condition score of does and exposure to sexually active bucks after exposure to long-day artificial photoperiod were examined in mature anovulatory French Alpine goat in Northern Mexico. In June, goats in good (2.3 +/- 0.2, scale 1 to 4; n = 10) or poor (1.6 +/- 0.3; n = 10) body condition were exposed during 15 day to sexually active bucks, which had been exposed to long photoperiod (16:8-h light-dark cycle, starting in December). A third group of goats in good body condition was exposed to bucks kept under the natural photoperiod of this region (26 degrees N). All goats in good body condition exposed to bucks treated with prolonged photoperiod exhibited estrus behavior, whereas only 50% of the does in poor body condition showed estrous behavior during the 15-day buck exposure. None of the does in good body condition showed estrus when exposed to bucks under natural photoperiod. These results revealed that a good body condition is required for maximum estrus response in anestrous Alpine goats and that exposure of bucks to long photoperiod in winter is essential for an adequate stimulus to reestablish estrus cycles in anovulatory Alpine does in Northern Mexico.

Sexual behavior of Pecari tajacu (Cetartiodactyla: Tayassuidae) during periovulatory and early gestation periods.

PubMed

da Silva, Suleima do Socorro Bastos; Le Pendu, Yvonnick; Ohashi, Otavio Mitio; Oba, Eunice; de Albuquerque, Natália Inagaki; Garcia, Alexandre Rossetto; Mayor, Pedro; de Araujo Guimarães, Diva Anelie

2016-10-01

The goal of this study was to describe the sexual behavior in female and male collared peccary. Twenty females and twelve males were monitored in familiar and non-familiar units for two 60 days periods. During both phases, we recorded 2747 sexual interactions initiated by 20 different females toward males and 4461 sexual interactions initiated by 12 males toward females. The frequency of sexual interactions initiated per female significantly increased from proestrus to estrus, and they were significantly more frequently courted. Females initiated olfactory inspections 15.42 times more and were mounted 22.6 times more during estrus than during proestrus. Nulliparous and primiparous females copulated only when exposed to non-parental males. After estrus, the frequency of sexual interactions received by females sharply decreased. One mating event was recorded during the first gestation week and 31 mountings were observed after the second week. In conclusion, the behavioral monitoring is a useful procedure for the recognition of estrus. Our results suggest that ovulation may be associated with the end of the estrus, which will support future work in assisted reproduction in this species. To promote good handling practices, females of reproductive age should be removed from their family unit of origin. Copyright © 2016 Elsevier B.V. All rights reserved.

A novel method of extraction of bamboo seed oil (Bambusa bambos Druce) and its promising effect on metabolic symptoms of experimentally induced polycystic ovarian disease

PubMed Central

Soumya, V.; Muzib, Y. Indira; Venkatesh, P.

2016-01-01

Objective: To evaluate the potential effect of bamboo seed oil in decreasing the major metabolic symptoms associated with letrozole-induced polycystic ovarian disease using female rat model. Materials and Methods: A new method of microwave-assisted extraction was developed. Female rats were grouped into four with six animals each. All rats were daily administered with letrozole (1 mg/kg b.wt.) for 21 days except control, and during this period, changes in estrous cycle were observed. After letrozole treatment, Group 2 was considered negative control, Groups 3 and 4 were treated orally with bamboo oil, 0.5 ml/kg b.wt. and 1 ml/kg b.wt., respectively, for 3 weeks (five consecutive estrus cycles). Various parameters such as estrus cycle, blood sugar level, lipid profile, and weights of reproductive system were determined. The characteristics of cystic ovaries were evaluated by histopathological studies. Results: The isolated bamboo oil restored estrus cyclicity showed hypoglycemic and hypolipidemic effects. 1 ml/kg b.wt. of bamboo oil showed a marked glucose reduction from 254.04 ± 2.08 to 92.6 ± 1.63, and levels of total cholesterol, very low-density lipoprotein, triglyceride were reduced from 186.45 ± 2.28, 30.07 ± 2.36, 100.36 ± 2.35 to 152.14 ± 2.63, 25.94 ± 1.66, 93.32 ± 1.09, respectively. Histopathological results showed the presence of ovulation and recovery from cystic ovaries. Conclusion: A novel and promising drug was isolated in the treatment and maintenance of various metabolic symptoms associated with polycystic ovary disease. PMID:27127318

Immunization against GnRF in adult cattle: a prospective field study.

PubMed

Hirsbrunner, Gaby; Rigert, Sarah; Janett, Fredi; Hüsler, Jürg; Schnydrig, Philipp; Lopez, Ester; Amatayakul-Chantler, Sue; Steiner, Adrian

2017-07-01

Suppression of cyclic activity in cattle is often desired in alpine farming and for feedlot cattle, not intended for breeding. A cattle specific anti-GnRF vaccine (Bopriva™) is registered for use in heifers and bulls in different countries. In adult cows vaccinated with Bopriva™, the median period until recurrence of class III follicles was 78 days from the day of the 2nd vaccination and reversibility could be proven, as out of 11 experimental cows 10 cows became pregnant at first, and one cow at second insemination. In the present study, 76 healthy, cyclic Eringer heifers and cows were vaccinated twice with Bopriva™ 3-7 weeks apart, to prevent estrus during alpine pasturing. Blood samples were taken for progesterone and GnRF antibody titer analysis on the day of inclusion (7-9 d before the first vaccination) and at the first vaccination. At the same time, gynaecological examinations were performed. When estrus occurred in the course of the alpine pasturing season, a gynaecological examination was done including analysis of a blood sample (progesterone, anti-GnRF antibody titer). Cows were followed for fertility out to 26 months post second vaccination. Median duration of estrus suppression was 191 days after the second vaccination (when the 2 vaccinations were given 28-35 days apart). From n = 13 cows showing signs of estrus on the alpine pasture, n = 7 could not be confirmed in estrus (serum progesterone value >2 ng/ml, no class III follicles seen using ultrasonography). Median duration between second vaccination and next calving was 496 days (25%/75% quartiles: 478/532 days). Bopriva™ induced a reliable and reversible suppression of estrus for more than 3 months in over 90% of the cows.

The effect of subclinical ketosis on activity at estrus and reproductive performance in dairy cattle.

PubMed

Rutherford, Andrew J; Oikonomou, Georgios; Smith, Robert F

2016-06-01

Our aims were to investigate the influence of subclinical ketosis (SCK) on physical activity at estrus using a neck accelerometer device and on future reproductive performance. Two hundred three Holstein-Friesian cows were studied on 3dairy farms in Northwest England between September 2013 and March 2014. Seventeen percent (35 of 203) of the enrolled cows were affected with SCK between 7 and 21d in milk, defined as a blood β-hydroxybutyrate concentration of 1.2 to 2.9mmol/L. Time to event analyses and multivariable regression analyses were used to assess the effect of SCK on reproductive performance and activity at estrus. The SCK cows exhibited a lower peak activity (measured as the number of standard deviations above mean activity) and shorter duration in activity clusters associated with first estrus and first insemination postpartum, compared with non-SCK cows. Peak activity and cluster duration associated with the insemination that led to a pregnancy were not different between SCK and non-SCK cows. Calving to first estrus, calving to first insemination, and calving to pregnancy intervals were prolonged in SCK cows. First insemination was 4.3 times (95% confidence interval=1.6 to 15.0) less likely to be successful in SCK cows compared with non-SCK cows. Adjusted mean number of inseminations per pregnancy was 2.8 for SCK cows and 2.0 for non-SCK cows. The current study confirms the long-lasting effects of SCK on reproductive efficiency. Furthermore, it is indicated that physical activity around estrus is reduced by SCK in early lactation, but this negative effect appears to diminish as cows progress through lactation. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The use of digital infrared thermal imaging to detect estrus in gilts.

PubMed

Sykes, D J; Couvillion, J S; Cromiak, A; Bowers, S; Schenck, E; Crenshaw, M; Ryan, P L

2012-07-01

Yorkshire/Landrace crossbred gilts (N = 32) were evaluated using digital infrared thermal imaging (DITI) to discriminate between estrus and diestrus phases of the porcine estrous cycle. Gilts (N = 32) were part of an ongoing reproductive efficiency study involving the use of raw soybean (RSB; N = 15) versus soybean meal (SBM; N = 17) as a source of dietary protein. Gilts were monitored daily for signs of estrus using a teaser boar. Thermal images of vulva surface temperatures (TEMP) were recorded at standing estrus and diestrus. Measurements for analysis included minimum (MIN), maximum (MAX), mean (AVG), and standard deviation (SD) of temperature gradients. At imaging, ambient (AMB) and rectal temperatures (RT) were recorded, and blood samples taken for serum progesterone (P(4)) concentration analysis (by RIA) to confirm stage of cycle. Mean serum progesterone values at estrus and diestrus were (mean ± SD) 1.0 ± 0.1 and 10.9 ± 0.8 ng/mL, respectively. Vulva MIN, MAX, and AVG thermal images were positively correlated with one another (P < 0.01), and were positively correlated with ambient temperature (P < 0.01). Vulva MAX and AVG thermal temperatures were greater (P < 0.05) at estrus than at diestrus (36.6 ± 0.2 °C and 33.4 ± 0.3 °C vs. 35.6 ± 0.3 °C and 31.8 ± 0.6 °C, respectively), whereas MIN and SD had no differences (P > 0.05) between stages of the cycle. No differences (P > 0.05) in RT were detected between stages and RT was not significantly correlated with vulva thermal images. Diet had no significant effect on RT or vulva temperature. Copyright © 2012. Published by Elsevier Inc.

Influence of the estrus cycle on the evaluation of a vaginal irritation study in intact and ovariectomized rats

PubMed Central

Ishii, Aiko; Ogawa, Bunichiro; Koyama, Tomoko; Nakanishi, Yutaka; Sasaki, Minoru

2017-01-01

When conducting vaginal irritation studies, ovariectomized rats or rabbits are typically used according to practical reports. In the present study, we evaluated the influence of the estrus cycle in a vaginal irritation study using intact rats and ovariectomized rats, which exhibit a late diestrus-like condition, to determine whether intact rats can be useful for evaluating vaginal irritancy. Rats were divided into 4 groups: proestrus, estrus, and metestrus or diestrus in intact rats and ovariectomized rats. All the rats in each group were treated with a vehicle or sodium dodecyl sulfate, as the irritant, in single-dose and 4-day repeat-dose vaginal irritation studies. Each rat’s vagina was examined histopathologically, and the irritation score was calculated using a semiquantitative scoring system. In the single-dose study, the irritation scores for the proestrus or ovariectomized groups treated with sodium dodecyl sulfate were higher than those of the estrus group or metestrus or diestrus group. In the 4-day repeat-dose study, a significant histopathological difference was not found among the intact rats (proestrus, estrus, and metestrus or diestrus groups), and the irritation score range of the intact rats was similar to that of the ovariectomized rats, though the mean score of the intact rats was slightly lower than that of the ovariectomized rats. These results suggest that intact rats might be well suited for 4-day vaginal irritation studies and useful for evaluating vaginal irritancy using not only the mean score, but also individual irritation score ranges, whereas the estrus cycle would need to be identified in single-dose vaginal irritation studies. PMID:28458454

Plasma progesterone levels and corpus luteum morphology in the female prairie dog (Cynomys ludovicianus).

PubMed

Foreman, D; Garris, D

1984-08-01

Plasma progesterone levels in female prairie dogs were determined by a radioimmunoassay specific for progesterone. Plasma progesterone levels were determined in samples taken before estrus, at estrus, during the luteal phase, and during anestrus from females maintained all year in the laboratory. Progesterone levels were also determined in plasma samples taken in the laboratory from two pregnant and three postparturient females captured in the field. Progesterone levels were low before estrus and continued low during estrus. They rose on the first week after estrus to 0.8 ng/ml or above and continued at or above this level for 9-14 weeks following estrus. Gestation in prairie dogs is 35 days in this species. Progesterone levels of three postparturient females were above 1.0 ng/ml for 7 weeks after their arrival in the laboratory. These females all had uterine scars showing that they had delivered their litters before they were captured. Two females were determined to be pregnant at the time of their capture. These females later reabsorbed their fetuses (determined by laparotomy). Progesterone values of samples from these females were all above 1.0 ng/ml except for one low value in one female which occurred 3 weeks after her capture and after reabsorption of her fetuses was in progress. The cells of the corpus lutea (CL) of nonpregnant, pregnant, and postparturient females had well-developed rings of cytoplasmic basophilia but as the CL regressed this pattern became disorganized and disappeared. The function of this basophilia is not known. The long luteal phase found in female prairie dogs is compared to those found in other species of mammals. This is the first annually breeding rodent reported to have a longer luteal phase that the period of gestation.

Effects of environmental lighting and tryptophan devoid diet on the rat vaginal cycle.

PubMed

Giammanco, S; Ernandes, M; La Guardia, M

1997-09-01

Cerebral serotonin level influences luteinizing hormone release and, consequently, ovulation. The present study evaluated the effects of precooked maize meal (polenta), a diet almost devoid of tryptophan the serotonin precursor on the alterations of the estrus cycle as measured by vaginal smears analysis in Wistar rats. Several conditions of environmental lighting were used in order to modify ovarian cycle: 1) natural alternating light/dark cycle; 2) continuous darkness; 3) continuous light by sodium steams: 4) continuous light by fluorescent neon tubes. Rats bred in continuous lighting showed estrus-proestrus rate significantly greater than rats bred in normal lighting or in continuous darkness. The feeding with precooked maize meal suppressed persistent estrus in rats bred in continuous lighting, and significantly cut down the estrus-proestrus frequency in any condition of environmental lighting. Our results lead to hypothesize that polenta diet, for its low tryptophan content, cutting down both tryptophan plasma content and serotonin neuronal synthesis, promotes luteinizing hormone peak.

Sex-steroid receptors, prostaglandin E2 receptors, and cyclooxygenase in the equine cervix during estrus, diestrus and pregnancy: Gene expression and cellular localization.

PubMed

Fernandes, Claudia B; Loux, Shavahn C; Scoggin, Kirsten E; Squires, Edward L; Troedsson, Mats H; Esteller-Vico, Alejandro; Ball, Barry A

2017-12-01

The cervix is a dynamic structure that undergoes dramatic changes during the estrous cycle, pregnancy and parturition. It is well established that hormonal changes, including estrogens, progestogens and prostaglandins, regulate the expression of key proteins involved in cervical function. The arachidonic acid cascade is important in the remodeling and relaxation of the cervix in the days preceding parturition. Despite the complexity of this mechanism, regulation of cervical function has received little study in the mare. Therefore, the objective of this study was to compare the expression of estrogen receptor α (ESR1) and β (ESR2), progesterone receptor (PGR), prostaglandin E2 type 2 (PTGER2) and type 4 (PTGER4) receptors as well as cyclooxygenase-1 (PTGS1) and -2 (PTGS2) in the equine cervical mucosa and stroma during estrus, diestrus and late pregnancy using qPCR. Immunohistochemistry was used to localize ESR1, ESR2, PGR, PTGER2 and PTGER4 receptors in these regions of the cervix. Relative mRNA expression of ESR1 and PGR was greater during estrus and diestrus than in late pregnancy in both the mucosa and stroma of the cervix. Expression of PTGER2 was highest in the cervical stroma during late pregnancy compared to either estrus or diestrus. Moreover, PTGS1 expression in mucosa and PTGS2 in stroma was greater during late pregnancy compared with estrus, but not diestrus. Immunostaining for ESR1, ESR2, PGR, PTGER2 and PTGER4 was consistently detected in the nucleus and cytoplasm of epithelium of the endocervix as well as the smooth muscle cytoplasm of the cervix in all stages evaluated. Immunolabeling in smooth muscle nuclei was detected for ESR1 and PGR in estrus, diestrus and late pregnancy, and for ESR2 in estrus and late pregnancy stages. The changes noted in late gestation likely reflect preparation of the equine cervix for subsequent parturition. Copyright © 2017 Elsevier B.V. All rights reserved.

Genomics and metabolomics of post-weaning return to estrus

USDA-ARS?s Scientific Manuscript database

The weaning-to-estrus interval is a multifaceted trait that has the potential to substantially improve production efficiency in today's global swine industry, if variation in this measure can be reduced. Systems-biology approaches should help close the knowledge gap and increase selection tools and ...

Intrauterine inoculation of minipigs with Chlamydia trachomatis during diestrus establishes a longer lasting infection compared to vaginal inoculation during estrus.

PubMed

Lorenzen, Emma; Follmann, Frank; Secher, Jan O; Goericke-Pesch, Sandra; Hansen, Mette S; Zakariassen, Hannah; Olsen, Anja W; Andersen, Peter; Jungersen, Gregers; Agerholm, Jørgen S

2017-06-01

Advanced animal models, such as minipigs, are needed for the development of a globally requested human Chlamydia vaccine. Previous studies have shown that vaginal inoculation of sexually mature Göttingen minipigs with Chlamydia trachomatis resulted in an infection lasting only 3-5 days. The aim of this study was to evaluate the effect of targeting the upper porcine genital tract by transcervical and transabdominal intrauterine inoculation, compared to previously performed vaginal inoculation. Furthermore, we investigated the effect of the hormonal cycle, estrus vs. diestrus, on the establishment of a C. trachomatis infection in the minipig. Targeting the upper genital tract (transcervical inoculation) resulted in a longer lasting infection (at least 7 days) compared to vaginal inoculation (3-5 days). When comparing intrauterine inoculation during estrus and diestrus, inoculation during diestrus resulted in a longer lasting infection (at least 10 days) compared to estrus (3-5 days). Furthermore, we found a significant C. trachomatis specific IFN-γ response in pigs inoculated during estrus correlating with the accelerated clearance of infection in these pigs. These findings suggest that for implementation of an optimal model of C. trachomatis in minipigs, inoculation should bypass the cervix and preferable be performed during diestrus. Copyright © 2017 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.

The Concentrations of Circulating Plasma Oxytocin and the Pattern of Oxytocin Release in Mare during Oestrus and after Ovulation

NASA Astrophysics Data System (ADS)

Bae, Sung Eun

Mares susceptible to persistent mating-induced endometritis (PMIE) accumulate intrauterine fluid after mating. One of the factors causing delayed uterine clearance is thought to be impaired uterine contractility. Oxytocin is central in controlling myometrial contractility. The objective of the present study was to describe peripheral oxytocin release during estrus and in the early postovulatory period in reproductively-normal mares and to compare the baseline circulating oxytocin concentrations in reproductively-normal mares and mares with PMIE. Blood samples were collected from reproductively-normal mares (n=5) from day -5 of estrus to day 2 postovulation and every 5 min for 30 min from reproductively-normal mares (n=5) and mares with PMIE (n=5) on day 3 of estrus. Pulsatile secretion of oxytocin was observed in all mares. Mean plasma oxytocin concentrations were significantly higher (P<0.05) in estrus (day -5 to day -2) than on the day of ovulation (day 0). After ovulation, plasma oxytocin concentrations tended to increase. On day 3 of estrus, plasma oxytocin concentrations were significantly higher (P<0.01) in reproductively-normal mares than in mares with PMIE. The results showed there is a significant difference in plasma oxytocin concentrations between mares to PMIE. The low plasma oxytocin concentrations in mares with PMIE may contribute to predisposing factors in their poor uterine clearance in these mares.

Sex differences in paradoxical sleep: influences of estrus cycle and ovariectomy.

PubMed

Fang, J; Fishbein, W

1996-09-23

Previously, we reported that paradoxical sleep (PS) is sexually dimorphic in mice and rats. Since some early studies indicate that PS is suppressed during proestrus night, it is important to know whether the estrus cycle and accompanying circulating ovarian hormones could explain the sexual dimorphism of PS. To examine this, sleep patterns of male rats were compared with those of normal cycling female rats and ovariectomized females in a 12:12 h light/dark cycle. Slow wave sleep and total sleep time are indistinguishable between the males, cycling females and ovariectomized females. However, normal males display significantly more PS than cycling females during both daytime and nighttime (average of all estrus stages). On the other hand, while ovariectomy has no visible effect on daytime sleep--the sexual dimorphism of PS is unchanged by ovariectomy--during nighttime, ovariectomy produces a selective increase of PS, eliminating the sex difference during the night. In sum, normal cycling females show no change in daytime sleep patterns across the estrus cycle, but have significantly less PS during proestrus nights than during metestrus and diestrus nights. The results indicate that the sex difference in nighttime PS is due to the suppression of PS by ovarian hormones during proestrus and, to a less extent, estrus nights. The sex difference in daytime PS, on the other hand, appears to be independent of circulating ovarian hormones.

Expression of aquaporin-7 and aquaporin-9 in tanycyte cells and choroid plexus during mouse estrus cycle.

PubMed

Yaba, A; Sozen, B; Suzen, B; Demir, N

2017-03-01

Tanycytes are special ependymal cells located in the ventrolateral wall and floor of the third ventricle having processes extending nuclei that regulate reproductive functions and around of vessels in median eminance. The aquaporins (AQPs) are a family of transmembrane proteins that transport water and glycerol. AQP-7 and -9 are permeable to other small molecules as glycerol and therefore called aquaglyceroporins. In this study, we aimed to show localization of AQP-7 and -9 in epithelial cells of choroid plexus and tanycytes during female mouse estrus cycle. AQP-7 and -9 proteins were detected in α2 and β1 tanycytes in prœstrus stage. Interestingly, there is no staining in estrus stage in any type of tanycytes. We observed weak immunoreactivity in α1, α2 and β1 tanycyte cells in metestrus stage for AQP-7 and α1 for AQP-9 protein. AQP-7 and -9 showed intense immunoreactivity in α2, β1 and β2 tanycyte cells during diestrus stage. Consequently, AQP-7 and -9 showed differential staining pattern in different stages of mouse estrus cycle. In the light of our findings and other recent publications, we suggest that AQP-7 and -9-mediated glycerol transport in tanycyte cells might be under hormonal control to use glycerol as a potential energy substrate during mouse estrus cycle. Copyright © 2016. Published by Elsevier Masson SAS.

Use of an electronic activity detection system to characterize estrus activity in crossbred beef heifers differing in follicle number

USDA-ARS?s Scientific Manuscript database

Increased numbers of antral follicles have been associated with decreased calving day, increased fertility, increased serum estradiol concentrations, increased serum progesterone concentrations, and increased estrus behavior in cattle. In addition, cows with increased fertility have been shown to h...

Effects of excess metabolizable protein on ovarian function and circulating amino acids of beef cows: 1. Excessive supply from corn gluten meal or soybean meal.

PubMed

Geppert, T C; Meyer, A M; Perry, G A; Gunn, P J

2017-04-01

In the dairy industry, excess dietary CP is consistently correlated with decreased conception rates. However, the source from which excess CP is derived and how it affects reproductive function in beef cattle is largely undefined. The objective of this experiment was to determine the effects of feeding excess metabolizable protein (MP) from feedstuffs differing in rumen degradability on ovulatory follicular dynamics, subsequent corpus luteum (CL) development, steroid hormone production and circulating amino acids (AA) in beef cows. Non-pregnant, non-lactating mature beef cows (n=18) were assigned to 1 of 2 isonitrogenous diets (150% of MP requirements) designed to maintain similar BW and body condition score (BCS) between treatments. Diets consisted of ad libitum corn stalks supplemented with corn gluten meal (moderate rumen undegradable protein (RUP); CGM) or soybean meal (low RUP; SBM). After a 20-day supplement adaptation period, cows were synchronized for ovulation. After 10 days of synchronization, gonadotropin releasing hormone (GnRH) was administered to reset ovarian follicular growth. Starting at GnRH administration and daily thereafter until spontaneous ovulation, transrectal ultrasonography was used to diagram ovarian follicular growth, and blood samples were collected for hormone, metabolite and AA analyses. After 7 days of visual detection of estrus, CL size was determined via ultrasound. Data were analyzed using the MIXED procedures of SAS. As designed, cow BW and BCS were not different (P⩾0.33). Ovulatory follicular wavelength, antral follicle count, ovulatory follicle size at dominance and duration of dominance were not different (P>0.13) between treatments. Cows supplemented with CGM had greater post-dominance ovulatory follicle growth, larger dominant follicles at spontaneous luteolysis, shorter proestrus, and larger ovulatory follicles (P⩽0.03) than SBM cows. No differences (P⩾0.44) in peak estradiol, ratio of estradiol to ovulatory follicle volume, or plasma urea nitrogen were observed. While CL volume and the ratio of progesterone to CL volume were not affected by treatment (P⩾0.24), CGM treated cows tended to have decreased (P=0.07) circulating progesterone 7 days post-estrus compared with SBM cows. Although total circulating plasma AA concentration did not differ (P=0.70) between treatments, CGM cows had greater phenylalanine (P=0.03) and tended to have greater leucine concentrations (P=0.07) than SBM cows. In summary, these data illustrate that excess MP when supplemented to cows consuming a low quality forage may differentially impact ovarian function depending on ruminal degradability of the protein source.

Role of exogenous estrogen in initiation of estrus and induction of an LH surge

USDA-ARS?s Scientific Manuscript database

Among cattle the LH surge that causes ovulation occurs shortly after the onset of a spontaneous estrus. In addition an injection of 100 'g of GnRH can induce an LH surge capable of inducing ovulation. We hypothesized that different preovulatory estradiol profiles would result in different ovulator...

Expression, regulation, and function of drug transporters in cervicovaginal tissues of a mouse model used for microbicide testing

PubMed Central

Zhou, Tian; Hu, Minlu; Pearlman, Andrew; Rohan, Lisa C.

2016-01-01

P-glycoprotein (P-gp), breast cancer resistance protein (BCRP), and multidrug resistance protein 4 (MRP4) are three efflux transporters that play key roles in the pharmacokinetics of antiretroviral drugs used in the pre-exposure prophylaxis of HIV sexual transmission. In this study, we investigated the expression, regulation, and function of these transporters in cervicovaginal tissues of a mouse model. Expression and regulation were examined using real-time RT-PCR and immunohistochemical staining, in the mouse tissues harvested at estrus and diestrus stages under natural cycling or after hormone synchronization. The three transporters were expressed at moderate to high levels compared to the liver. Transporter proteins were localized in various cell types in different tissue segments. Estrous cycle and exogenous hormone treatment affected transporter mRNA and protein expression, in a tissue- and transporter-dependent manner. Depo-Provera-synchronized mice were dosed vaginally or intraperitoneally with 3H-TFV, with or without MK571 co-administration, to delineate the function of cervicovaginal Mrp4. Co-administration of MK571 significantly increased the concentration of vaginally-administered TFV in endocervix and vagina. MK571 increased the concentration of intraperitoneally-administered TFV in the cervicovaginal lavage and vagina by several fold. Overall, P-gp, Bcrp, and Mrp4 were positively expressed in mouse cervicovaginal tissues, and their expression can be regulated by the estrous cycle or by exogenous hormones. In this model, the Mrp4 transporter impacted TFV distribution in cervicovaginal tissues. PMID:27453435

Effect of dietary supplementation of omega-3 polyunsaturated fatty acid (PUFA) rich fish oil on reproductive performance of the goat (Capra hircus).

PubMed

Mahla, Ajit Singh; Chaudhari, Ravjibhai K; Verma, Atul Kumar; Singh, Amit Kumar; Singh, Sanjay Kumar; Singh, Gyanendra; Sarkar, Mihir; Dutta, Narayan; Kumar, Harendra; Krishnaswamy, Narayanan

2017-09-01

Dietary supplementation of n-3 PUFA decreases the luteolytic PGF 2α and improves the pregnancy rate in the dairy cow. However, its effect in the goat is not known. Accordingly, we studied the effect of supplementation of n-3 PUFA rich Fish oil (FO) on different reproductive events in the goat. Cycling goats (n = 30) were divided into two equal groups and fed an isocaloric and isonitrogenous diet supplemented with either FO (TRT; n = 15) or palm oil (PO) (CON; n = 15) @ 0.6 mL/kg body weight for 72 days during the breeding season. Estrus synchronization was done on day 25 and 36 of supplementation using two PG regimen and the goats in estrus were bred. Mean interval from PGF 2α administration to the onset of estrus was 12 h longer (P < 0.05) in the TRT group than that of CON. The number of preovulatory follicles (POF) and ovulation rate was significantly higher in FO supplemented goats (P < 0.05) by 39.64 and 41.35%, respectively. Though the corpus luteum diameter was significantly higher (P < 0.05) on day 5, 8 and 11 post-breeding in the TRT group, mean serum progesterone (P 4 ) did not differ significantly (P > 0.05). Mean concentration of serum estradiol (E 2 ) was significantly (P < 0.01) lower in the FO supplemented group during day 0-60 post-breeding which could be due to significantly low serum cholesterol (P < 0.01). Though the serum concentration of PGF 2α metabolite (PGFM) and PGE 2 metabolite (PGEM) in the pregnant goats was significantly (P < 0.05) lower in the TRT group on day 16 and 17 post-breeding, the ratio of PGEM to PGFM remained unaffected suggesting a favourable effect of FO supplementation on the early pregnancy. The number of embryos, twinning rate and kidding rate were high in FO supplemented group though it was non-significant. However, gestation length, birth weight of kids and neonatal behaviour were comparable between the groups (P > 0.05). In conclusion, supplementation of n-3 PUFA rich FO significantly increased the number of POF and ovulation rate with numerical increase in the kidding rate. Further, it decreased the serum E 2 and PGFM during the critical window of pregnancy recognition in the doe. Copyright © 2017 Elsevier Inc. All rights reserved.

Survey of reproduction management on Canadian dairy farms.

PubMed

Denis-Robichaud, J; Cerri, R L A; Jones-Bitton, A; LeBlanc, S J

2016-11-01

The objectives of this study were to (1) quantify current reproduction management practices, and (2) assess the association between these practices and herd reproductive performance on dairy farms in Canada. A bilingual survey was developed, validated, and administered from March to May 2014 to collect general and reproduction management and performance measures [annual 21-d pregnancy rate (PR), 21-d insemination rate (IR), and conception risk (CR)]. Associations between management practices and reproductive performance measures were tested using linear regression models. A total of 832 questionnaires were completed online and by mail, representing a response rate of 9%. On average, farms had 77 lactating cows (median=50) and 13 dry cows (median=10), and Holstein was the most common breed (92% of herds). Lactating cow housing was tiestall on 61% of the farms, freestall on 37%, and bedded pack on 2%. The average voluntary waiting period was 58 d in milk (DIM). The main reproduction management practice per farm was defined as the means employed for >50% of inseminations. Farms reported their main reproduction management practice for first and subsequent inseminations, respectively, as visual estrus detection (51 and 44% of herds), timed AI (21 and 23% of herds), automated activity monitoring (AAM; 10 and 10% of herds), other management practice (bulls; 2 and 2% of herds), and a combination of management practices (16 and 21% of herds). On farms using visual estrus detection, cows were observed for signs of estrus on average 3.5 times per day, for an average total of 36 min/d. The most common use of reproductive hormones was to synchronize ovulation using Ovsynch (58% of the farms). Average PR, IR, and CR were 17.6, 44.1, and 40.5%, respectively. In linear regression analyses adjusted for confounders, pregnancy rate was significantly associated with geographic region, housing (tiestall: PR=15.4%, freestall: PR=17.6%), herd size (<50 lactating cows: PR=16.2%, 50-100 cows: PR=16.5%, >100 cows: PR=17.8%), voluntary waiting period (≤60 DIM: PR=17.6%, >60 DIM: PR=15.9%), and frequency of insemination per day (once daily: PR=16.6%, twice or more daily: PR=18.1%). The main reproduction management practice at first and subsequent inseminations was divergently associated with IR and CR, but not with PR (visual heat detection: PR=17.4%, timed AI: PR=18.4%, AAM: PR=17.1%, combined practices: PR=18.2%). Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Detection of estrus in dairy cows by electrical measurements of vaginal mucus and by milk progesterone.

PubMed

Gartland, P; Schiavo, J; Hall, C E; Foote, R H; Scott, N R

1976-05-01

Electrical resistance (ohms) of mucus were analyzed in 20 postpartum Holstein cows by use of a probe inserted into the anterior vagina every other day for 30 days. Composite milk samples were taken on the same day, and progesterone was determined by radioimmunoassay. Cows were observed twice daily for standing estrus and reproductive organs palpated weekly per rectum (rectal palpation). Fifteen cows which were cycling showed increasing progesterone 6 to 7 days after the onset of estrus with values of 8.1 to 10.0 ng progesterone/ml milk on days 10 to 17. Concentrations had declined rapidly 2 days before onset of the next estrus. Progesterone in milk was affected by cow and by day of the cycle. Electrical resistance followed a similar cyclical pattern, but variability was large and only cows differed. The correlation between milk progesterone and mucus resistance was .22. Progesterone concentrations for four cows with follicular cysts fluctuated randomly with a mean of 2.6 ng/ml. Mean resistance of vaginal mucus was 44 omega for both cycling and cystic cows, indicating that a single measurement of electrical resistance every 2nd day was unreliable in distinguishing physiological states. One cow had high progesterone in milk on days 19 to 25 and was diagnosed pregnant by rectal palpation 3 wk later. Cows were not seen in estrus 28% of the time when milk progesterone and rectal palpation indicated they were in the follicular phase of the estrous cycle and were cycling.

Hot topic: Comparison of sex-sorted and conventional semen within a fixed-time artificial insemination protocol designed for dairy heifers.

PubMed

Mallory, D A; Lock, S L; Woods, D C; Poock, S E; Patterson, D J

2013-02-01

The objective was to compare pregnancy per AI (P/AI) with conventional (CON) or sex-sorted (SS) semen from a single sire within a fixed-time AI (FTAI) program designed for dairy heifers. Holstein heifers (n=240) were assigned to treatment (CON or SS) according to body weight and reproductive tract score. All heifers underwent FTAI by using the "Show-Me-Synch" protocol [controlled internal drug release (CIDR) insert from d 0 to 14 followed by PGF(2α) (25mg i.m.) 16d after insert removal (d 30) with GnRH (100 µg i.m.) and FTAI at 66 h after PGF(2α)]. A single professional technician performed the FTAI. Heifers were fitted with heat detection patches at PGF(2α) to characterize estrous response. Estrous response did not differ between CON (63/120; 53%) and SS (70/120; 58%) treatments. The CON heifers, however, achieved greater FTAI P/AI (82/120; 68%) compared with SS (45/120; 38%) heifers. The P/AI did not differ for CON heifers that exhibited or failed to exhibit estrus before FTAI [44/63 (70%) vs. 38/57(67%), respectively]. For SS heifers, however, those that exhibited estrus had greater P/AI compared with those that failed to exhibit estrus [32/70 (46%) vs. 13/50 (26%)]. Pregnancy per AI resulting from FTAI was greater for heifers that were inseminated with CON semen compared with those that received SS semen. The expression of estrus before FTAI did not affect P/AI when CON semen was used, whereas the P/AI with SS semen was greater for heifers detected in estrus. Further studies are required to develop strategies for using sex-sorted semen when inseminating heifers at predetermined fixed times on the basis of expression of estrus before FTAI. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Estrus induction and fertility rates in response to exogenous hormonal administration in postpartum anestrous and subestrus bovines and buffaloes.

PubMed

Honparkhe, M; Singh, Jagir; Dadarwal, D; Dhaliwal, G S; Kumar, Ajeet

2008-12-01

A total of 130 animals (82 cattle, 48 buffaloes) with histories of anestrous 60-90 days post-partum and belonging to different agroclimatic zones of Punjab were subjected to rectal palpation and blood samplings at least three times at weekly intervals. The body condition score (BCS) of each animal was also recorded. The animals were divided into two groups; viz., true anestrous (Gp-I) and subestrus (Gp-II) through rectal palpation of ovaries and plasma progesterone (P4) concentrations. Furthermore, the Gp I and II animals were divided into treatment (Gp Ia, 40 cattle and 16 buffaloes; Gp IIa, 12 cattle and 14 buffaloes) and control groups (Gp Ib, 20 cattle and 8 buffaloes; Gp IIb, 10 cattle and 10 buffaloes). True anestrous animals (Gp Ia) were treated with 3 injections of hydroxyprogesterone caproate (750 mg, i.m.) at 72-hr intervals followed by injection of equine chorionic gonadotropin (eCG; 750 I.U., i.m.) 72 hr after the last progesterone injection. The animals were bred at the first estrus after the induced one. The first service conception rate (FSCR), overall conception rate (OCR), services per conception and pregnancy rate of the true anestrous treated cattle (Gp Ia) were 44.4%, 48.0%, 2.08 and 60.0%, respectively. In the true anestrous control cattle (Gp Ib), only five that were observed to be in estrus failed to conceive. In the anestrous treated buffaloes (Gp Ia), the FSCR, OCR, services per conception and pregnancy rate were 50.0%, 62.5%, 1.6 and 62.5%, respectively. No buffalo amongst true anestrous control (Gp Ib) showed estrus. The subestrus animals (Gp IIa) were administered Prostaglandin F(2alpha) (PGF(2alpha); 25 mg Dinoprost, i.m.) and bred at induced estrus. Amongst the Gp IIa animals, all cattle (100%) and twelve buffaloes (85.7%) responded to treatment. Of these animals, the FSCR and pregnancy rate at induced estrus in the cattle were 50.0% each, whereas they were 66.6% and 57.1%, respectively, in the buffaloes. The subestrus control animals (Gp IIb) remained infertile. In summary, the plasma P(4) profile can be used to differentiate true anestrous and subestrus animals and thus to determine a hormonal therapy. Furthermore, fertile estrus can be induced with hormonal therapy in anestrous and subestrus bovines.

Effects of P.G. 600 on the onset of estrus and ovulation rate in gilts treated with Regu-mate.

PubMed

Estienne, M J; Harper, A F; Horsley, B R; Estienne, C E; Knight, J W

2001-11-01

Three experiments assessed the onset of estrus and ovulation rate in gilts treated with gonadotropins after the withdrawal of an orally active progestin. In Exp. 1, all cycling gilts received the progestin (Regu-mate; Intervet America Inc., Millsboro, DE) at a rate of 15 mg/d for 18 d. Twenty-four hours after the last feeding of Regu-mate, 32 gilts received an i.m. injection of 400 I.U. PMSG and 200 I.U. hCG (P.G. 600, Intervet America, Inc.), and 32 gilts received an i.m. injection of deionized water. The percentage of gilts displaying estrus < or = 7 d (P = 0.64) and the injection-to-estrus interval (P = 0.37) were similar for P.G. 600-treated gilts (93.8% and 4.1 +/- 0.1 d) and controls (90.6% and 4.3 +/- 0.1 d). Ovulation rate was greater (P < 0.01) in P.G. 600-treated gilts (28.8 +/- 1.1) compared with controls (17.4 +/- 1.1). In Exp. 2, 58 cycling gilts received Regu-mate (15 mg/d) for 18 d. Twenty-four hours after Regu-mate withdrawal, gilts received i.m. P.G. 600 or water (n = 29/treatment). Gilts were bred via AI 12 and 24 h after first detection of estrus. The percentage of gilts displaying estrus < or = 7 d (P = 0.45) and the injection-to-estrus interval (P = 0.27) were similar for P.G. 600-treated gilts (82.7% and 4.0 +/- 0.1 d) and controls (89.7% and 4.2 +/- 0.1 d). Ovulation rate was greater (P < 0.01) in P.G. 600-treated gilts (26.2 +/- 1.8) compared with controls (18.1 +/- 1.7). Pregnancy rate (P = 0.71) and the number of live embryos at d 30 postmating (P = 0.40) were similar for P.G. 600-treated gilts (91.7% and 15.6 +/- 1.2) and controls (88.5% and 14.1 +/- 1.2). In Exp. 3, prepubertal gilts (142.6 +/- 0.7 d of age) received Regumate (15 mg/d) (n = 20) or a control diet not including Regu-mate (n = 20) for 18 d. Twenty-four hours after Regu-mate withdrawal, all gilts received i.m. P.G. 600. The percentage of gilts displaying estrus < or = 7 d (P = 0.49) and the P.G. 600-to-estrus interval (P = 0.69) were similar for Regu-mate-fed gilts (95% and 4.3 +/- 0.2 d) and controls (88.9% and 4.2 +/- 0.2 d). Ovulation rate was similar (P = 0.38) for Regu-mate fed gilts (16.6 +/-1.6) and controls (14.4 +/- 1.8). In cycling gilts, administration of P.G. 600 after withdrawal of Regu-mate increased ovulation rate, but not litter size at d 30 postmating. There was no beneficial effect of Regu-mate pretreatment on the response to P.G. 600 in prepubertal gilts.

Evaluation of a modified GnRH-based timed-AI protocol associated with estrus detection in beef heifers inseminated with sex-selected or conventional semen.

PubMed

Colazo, M G; Whittaker, P; Macmillan, K; Bignell, D; Boender, G; de Carvalho Guimaraes, R; Mapletoft, R J

2018-05-31

The main objective was to compare pregnancy per AI (P/AI) between sex-selected and conventional semen in cyclic beef heifers subjected to a 5-day Co-synch plus CIDR protocol and evaluated the usefulness of an estrus detection (ED) aid to identify heifers that were most likely to conceive. This study also determined if the expression of estrus before timed-AI (TAI) would be associated with increased P/AI in acyclic heifers inseminated with conventional semen. Heifers (n = 1690; 320-523 kg of body weight, and 13-15 mo of age) at three locations over 2 years were scanned by ultrasonography to determine cyclicity (presence of luteal tissue) and reproductive tract normalcy. Cyclic heifers (n = 1331) received a progesterone releasing device (CIDR) on Day 0, CIDR removal and 500 μg of cloprostenol (PGF) on Day 5, and 100 μg of GnRH along with TAI on Day 8. Acyclic heifers (n = 275) received the same treatment with the addition of GnRH on Day 0. On Day 5, all heifers received ED patches (Estrotect™) that were scored from 0 to 3, based on color change between initial application and Day 8; 0 = unchanged, 1 = ≤ 50% color change, 2 = > 50% color change, 3 = missing. Estrus was defined to have occurred when an ED patch was scored 2 or 3. Cyclic heifers were inseminated with either frozen-thawed sex-selected or conventional semen from either of three sires available commercially (two per year). Acyclic heifers were inseminated with conventional semen. Pregnancy diagnosis was performed by transrectal ultrasonography 28 or 48 d after TAI, depending on management. The percentage of cyclic heifers was 83.9% and the average estrus response was 63.8%. P/AI was greater (P < 0.01) in cyclic compared to acyclic heifers (53.3 vs. 36.0%) and tended to be greater (P = 0.07) for conventional semen (52.3 vs. 47.6%), despite all acyclic heifers being inseminated with conventional semen. Heifers with an ED patch scored 2 (61.1%) or 3 (58.6%) had greater (P < 0.01) P/AI than those scored 0 (31.8%) or 1 (33.1%), regardless of semen type. Pregnancy per AI was greater (P < 0.01) for heifers detected in estrus (60.6 vs. 32.3%). In cyclic heifers that did not exhibit estrus, P/AI was lower (P < 0.01) in those inseminated with sex-selected semen (27.8 vs. 45.9%), while in heifers that exhibited estrus, P/AI only tended to be lower (P = 0.08; 56.7 vs. 65.5%). In summary, P/AI was greater in cyclic heifers, in those inseminated with conventional semen and in those exhibiting estrus before TAI. The ED patches were considered useful to identify animals for TAI with sex-selected semen and could be used to increase the adoption of this technology in beef herds. Copyright © 2018. Published by Elsevier Inc.

[Hormonal methods of increasing fertility in swine].

PubMed

Kostov, L; Radev, G; Andreev, A

1976-01-01

Experiments were carried out to raise the conception rate in sows during the summer season under industrial conditions of breeding. Eight test groups of 365 animals were formed as well as four control ones with 137 pigs. The sucking period lasted 28 to 33 days. When in estrus the sows were mated with boars twice at a 24-hour interval. In five groups that were dried up from July to September was recorded the effect of several kinds of gonadotropic hormones administered alone or in combination with vitamin E and steroid hormones -- Gravohormone Tolligon, an oil emulsion of PMS (500 IU), with 250 Chorulon and 2 mg estradiol benzoicum; an oil solution of PMS (500 IU) with 2 mg estradiol, 25 mg testosterone and 30 mg vitamin E. During the same period three other groups of test sows were formed to use steroid hormones such as Gravignost, an oil solution of 2 mg estradiol benzoicum, and 40 mg testosterone propionate as well as the same preparation in combination with 30 mg vitamin E. The deterioration of the temperature and humidity regime in the summer at the industrial pig-breeding complexes was shown to inhibit the manifestation of estrus and lower the conception rate in sows. Either alone or in combination with vitamin E and estradiol the gonadotropic hormones largely raised the per cent of animals manifesting estrus for ten days in summer after weaning their piglets (89 to 100 per cent) as well as the number of lively born offsprings per sow (9.8 to 11.3). The optimal doses used were as follows: Gravohormone, 13--14 IU/kg liveweight; Folligon or PMS, 6--7 IU per kg; and choriogonadotropin at the rate of 500 IU per sow. One the other hand, the steroid hormonal preparations bring about estrus of a lower quality leading to a low conception rate and fertility at first insemination, disturb the sexual cyclicity. They should not be administered alone as cycle starters in pig-breeding.

ROLE OF STEROID HORMONES AND DECIDUAL INDUCTION IN THE REGULATION OF ADENOSINE DIPHOSPHORIBOSYL TRANSFERASE ACTIVITY IN RAT ENDOMETRIUM

EPA Science Inventory

To assess the effect of ovarian steroid hormones on enzyme activity, adenosine diphosphoribosyl transferase (ADPRT) was measured in endometrial nuclei isolated on estrus and on d 4 from rats ovariectomized on estrus (d 0) and treated d 0-3 with (a) vehicle, (b) 1 ug estrone/d (E)...

Ovarian reaction and estrus manifestation in delayed puberty gilts after treatment with equine chorionic gonadotropin

USDA-ARS?s Scientific Manuscript database

Prolonged pre-insemination anestrus (estrus not detected until 8 mo of age, i.e. delayed puberty) is the major reason for culling about 30% of the total number of gilts selected for reproduction at the large breeding farm units in Vojvodina (Republic of Serbia). It is important to determine whether...

GnRH-agonist induction of fertile estrus with either natural mating or artificial insemination, followed by birth of pups in gray wolves (Canis lupus).

PubMed

Asa, Cheryl S; Bauman, Karen; Callahan, Peggy; Bauman, Joan; Volkmann, Deitrich H; Jöchle, Wolfgang

2006-10-01

Although captive populations of endangered species such as the Mexican gray wolf (Canis lupus baileyi) can benefit from artificial insemination to accomplish genetic exchange, reliable techniques for timing insemination are lacking. We used the generic gray wolf (C. lupus) to test the efficacy of a short-acting GnRH-agonist implant, deslorelin, for inducing estrus. Of five females receiving implants on 17 or 18 January 2003, two mated naturally 10-17 days later, and the others were artificially inseminated using fresh semen, one on day 7 and all three on day 11. Relaxin tests revealed that one artificially inseminated female and both naturally mated females were pregnant on 1 March, and all three gave birth to healthy puppies on 4-6 April. Of the artificially inseminated females, only the one who subsequently conceived and gave birth was judged to be in cytologic estrus at the time of insemination. Two females were treated again with deslorelin on 12 January 2004, followed by collection of fecal samples for hormone analysis. One female, who was housed with a male, copulated on day 17 but did not conceive; the other was not with an adult male. Fecal progestin and estrogen profiles suggested that estrus, but not ovulation, was induced. These results indicated that deslorelin could induce fertile estrus in the gray wolf, although individual response varied. Further investigation is needed to better define and control the interval between implant insertion and ovulation for optimal timing of insemination.

Effect of season on reproductive behaviors and fertilization success in cavies (Cavia aperea).

PubMed

Hribal, Romy; Rübensam, Kathrin; Bernhardt, Sandra; Jewgenow, Katarina; Guenther, Anja

2018-04-05

Finding the optimal timing for breeding is crucial for small mammals to ensure survival and maximize lifetime reproductive success. Species living in temperate regions therefore often restrict breeding to seasons with favorable food and weather conditions. Although caviomorph rodents such as guinea pigs are described as non-seasonal breeders, a series of recent publications has shown seasonal adaptations in litter size, offspring birth mass and maternal investment. Here, we aim to test if seasonal patterns of litter size variation found in earlier studies, are mediated by seasonal differences in female estrus length, fertilization rate and mating behavior. The female estrus period was longer in fall compared to all other seasons (p < 0.001), frequently lasting 7-9 days while estrus in spring usually lasted less than 2 days. In fall, females mated later during estrus (p < 0.001), resulting in reduced fertilization rates (p < 0.001). Fertilization rate was well above 95% in summer while it dropped to less than 85% in fall and winter. While none of the male mating characteristics such as number and duration of copulations differed across seasons, the number of mating bouts was reduced in fall (p = 0.04). Finally, the developmental stages of flushed embryos were more diverse in spring and summer compared to fall and winter. These results suggest that seasonal differences in fertilization rate and quality of implanted embryos are mediated by female estrus length and timing and intensity of mating behavior. Together, these effects contribute to the observed differences in litter size across seasons. Copyright © 2018 Elsevier Inc. All rights reserved.

Estrous cycle regulatory mechanisms of the uterus are altered in cows that do not demonstrate behavioral estrus during an ovulation induction protocol

USDA-ARS?s Scientific Manuscript database

Estrus is the start of an estrous cycle in cows, and triggers several precisely timed events including receptivity to the bull, ovulation, conception, formation of the corpus luteum, and recognition of pregnancy. In the absence of a pregnancy signal, the corpus luteum (CL) must regress in response ...

Impact of estrus expression and conceptus presence on plasma and uterine glucose concentrations up until maternal recognition of pregnancy in beef cattle

USDA-ARS?s Scientific Manuscript database

Glucose is an essential component of uterine luminal fluid (ULF), it is a major energy source utilized by the conceptus for growth and development. Previously we reported increased concentrations of glucose in the ULF of cows that exhibited estrus, and observed differences in glucose transporter tr...

Selecting Female Mice in Estrus and Checking Plugs.

PubMed

Behringer, Richard; Gertsenstein, Marina; Nagy, Kristina Vintersten; Nagy, Andras

2016-08-01

The female mouse estrous cycle is divided into four phases: proestrus (development of ovarian follicles), estrus (ovulation), metestrus (formation of corpora lutea), and diestrus (beginning of follicle development for next ovulation and elimination of previous oocytes). The appearance of the epithelium of the external genitalia is used to identify the stage of the estrous cycle of a female mouse. This is usually easier to see in strains with either no or only light skin pigmentation. By examining the color, moistness, and degree of swelling of the vagina, females in estrus can readily be identified. To set up the matings, females are examined in the afternoon, and those in estrus are placed into the cages with males (one or two females in each cage with one male). Usually, 50% or more of the selected females will mate. The presence of a vaginal copulation plug next morning indicates that mating has occurred, but it does not mean that a pregnancy will result even if proven breeder fertile males were used. It is important to check vaginal plugs early in the morning because they fall out or are no longer detectable ~12 h after mating or sometimes earlier. © 2016 Cold Spring Harbor Laboratory Press.

Reproduction in female yaks (Bos grunniens) and opportunities for improvement.

PubMed

Zi, Xiang-Dong

2003-03-01

This paper reviews seasonal breeding, puberty, postpartum anestrus, embryonic loss and calf survival and their constraints in female yaks. Methods for improving fertility in postpartum yak cows are also considered. Yaks are seasonal breeders with mating and conception restricted in the warm season. Puberty generally occurs in the 2nd to the 4th warm season following birth, i.e. between 13 and 36 months of age. The cows usually have a long postpartum anestrus period; only a small proportion of the cows return to estrus in the 1st breeding season after calving, most come into estrus in the 2nd and 3rd years. Nutritional status is the most important determinant of reproduction in female yaks. Reproductive success is a direct result of the availability of pasture determined by climate, season, and management practices. Milking delays puberty by reducing milk intake (restricted suckling) and growth rate for the calf. Milking interferes with grazing and prolongs the duration of postpartum acyclicity in cows. Calves born early in the season have a longer suckling season than those born later in the season before the onset of winter. Thus, they can have their first cycle in the breeding season of the following year, while those born late in the season may not have their first estrus until 25 or 26 months of age. Cows calving early in the season are more likely to return to estrus in the year of calving because they have a longer period to recover from the demand on body reserves before the onset of winter. Inbreeding in smallholder yak farms is also discussed and minimizing inbreeding by exchanging bulls among different herds is suggested. Reproductive efficiency can be improved by nutritional supplementation during the winter, however, the most cost-effective and practical strategy for this needs to be determined. Early weaning or restricted suckling may shorten the duration of postpartum acyclicity, however, it is impractical due to reduced growth rates and increased winter mortality of early weaned calves. A single treatment with either GnRH, or PGF(2alpha)+GnRH can successfully induce estrus in yak cows that calved in previous years (with or without calf) but did not calve in the current year, however, it has little effect in cows nursing a calf born in the current year. The effects of administration of exogenous progestogens plus GnRH on the fertility of yak cows are worthy of further study.

Association between preovulatory concentrations of estradiol and expression of uterine milk protein precursor, inhibin beta A, Period 1, proenkephalin-A, and receptors for oxytocin, progesterone, and estradiol

USDA-ARS?s Scientific Manuscript database

Cows that did not exhibit standing estrus around the time of gonadotropin-releasing hormone (GnRH)-induced ovulation had decreased pregnancy success compared to cows that exhibited estrus. Therefore, the objective of the present experiment was to characterize changes in expression of uterine milk pr...

Increase of essential amino acids in the bovine uterine lumen during preimplantation development.

PubMed

Groebner, Anna E; Rubio-Aliaga, Isabel; Schulke, Katy; Reichenbach, Horst D; Daniel, Hannelore; Wolf, Eckhard; Meyer, Heinrich H D; Ulbrich, Susanne E

2011-05-01

Amino acids (AAs) are crucial for the developing conceptus prior to implantation. To provide insights into the requirements of the bovine embryo, we determined the AA composition of the uterine fluid. At days 12, 15, and 18 post-estrus, the uteri of synchronized pregnant and non-pregnant Simmental heifers were flushed for the analysis of 41 AAs and their derivatives by liquid chromatography-tandem mass spectrometry. The ipsilateral endometrium was sampled for quantitative PCR. In addition to a pregnancy-dependent increase of the essential AAs (P<0.01), we detected elevated concentrations for most non-essential proteinogenic AAs. Histidine (His) and the expression of the His/peptide transporter solute carrier 15A3 (SLC15A3) were significantly increased at day 18 of pregnancy in vivo. In addition, SLC15A3 was predominantly stimulated by trophoblast-derived interferon-τ in stroma cells of an in vitro co-culture model of endometrial cells. Our results show an increased concentration of AAs most likely to optimally provide the elongating pre-attachment conceptus with nutrients.

Conference lecture: influence of stress on estrus, gametes and early embryo development in the sow.

PubMed

Einarsson, S; Brandt, Y; Rodriguez-Martinez, H; Madej, A

2008-11-01

Systems with loose-housed sows have become common. Regrouping, which is commonly done after weaning and may coincide with many important reproductive events, causes stressful situations with elevated blood cortisol concentrations. Depending on group size, approximately 2-7 d are required for a new group of sows to become relatively stable. In a series of studies, the social stress after regrouping was simulated with repeated adrenocorticotrophic hormone (ACTH) treatments for approximately 48h. Sows were allocated into control and experimental groups, fitted with jugular catheters, and blood samples were collected every 2 or 4h. Follicular development and ovulation were monitored by transrectal ultrasonography every 4h. Simulated stress during pro-estrus prolonged estrus and disturbed the follicular growth and ovulation. Giving ACTH during estrus elevated concentrations of cortisol and progesterone, and changed the intraluminal environment, including exaggerated amounts of mucus in the UTJ and isthmus. Although ACTH had no effect on the time of ovulation (relative to onset of standing estrus), or on embryo development, fewer oocytes/embryos were retrieved from the ACTH group than from the control group (51% vs. 81%, P<0.05), and there was a tendency towards faster embryo transportation to the uterus. Short-term fasting after ovulation had an unfavourable effect on sperm numbers in UTJ/isthmus, cleavage rate of fertilized ova, as well as ova transport through the isthmic part of the oviduct. Treatment with ACTH after ovulation reduced numbers of spermatozoa at the zona pellucida and retarded cleavage rate of fertilized ova. Therefore, the timing of stress seemed to be an important factor regarding effects on reproductive events.

Nutrient restriction induces failure of reproductive function and molecular changes in hypothalamus-pituitary-gonadal axis in postpubertal gilts.

PubMed

Zhou, Dongsheng; Zhuo, Yong; Che, Lianqiang; Lin, Yan; Fang, Zhengfeng; Wu, De

2014-07-01

People on a diet to lose weight may be at risk of reproductive failure. To investigate the effects of nutrient restriction on reproductive function and the underlying mechanism, changes of reproductive traits, hormone secretions and gene expressions in hypothalamus-pituitary-gonadal axis were examined in postpubertal gilts at anestrus induced by nutrient restriction. Gilts having experienced two estrus cycles were fed a normal (CON, 2.86 kg/d) or nutrient restricted (NR, 1 kg/d) food regimens to expect anestrus. NR gilts experienced another three estrus cycles, but did not express estrus symptoms at the anticipated fourth estrus. Blood samples were collected at 5 days' interval for consecutive three times for measurement of hormone concentrations at the 23th day of the fourth estrus cycle. Individual progesterone concentrations of NR gilts from three consecutive blood samples were below 1.0 ng/mL versus 2.0 ng/mL in CON gilts, which was considered anestrus. NR gilts had impaired development of reproductive tract characterized by absence of large follicles (diameter ≥ 6 mm), decreased number of corepus lutea and atrophy of uterus and ovary tissues. Circulating concentrations of IGF-I, kisspeptin, estradiol, progesterone and leptin were significantly lower in NR gilts than that in CON gilts. Nutrient restriction down-regulated gene expressions of kiss-1, G-protein coupled protein 54, gonadotropin-releasing hormone, estrogen receptor α, progesterone receptor, leptin receptor, follicle-stimulating hormone and luteinizing hormone and insulin-like growth factor I in hypothalamus-pituitary-gonadal axis of gilts. Collectively, nutrient restriction resulted in impairment of reproductive function and changes of hormone secretions and gene expressions in hypothalamus-pituitary-gonadal axis, which shed light on the underlying mechanism by which nutrient restriction influenced reproductive function.

Influence of continuous illumination on estrous cycle of rats: time course of changes in levels of gonadotropins and ovarian steroids until occurrence of persistent estrus.

PubMed

Takeo, Y

1984-08-01

Plasma concentrations of LH, FSH, 17 beta-estradiol, estrone and progesterone were determined chronologically by radioimmunoassays in two groups of adult female rats exposed to continuous illumination (LL). Group 1 rats showing vaginal estrous cycles were sacrificed at 3- to 6-hour intervals during late proestrus through early estrus of the first 5 cycles after exposure to LL. Group 2 animals which displayed persistent vaginal estrus in an early period of exposure to LL were killed on the 2nd, 3rd, 4th, 5th and 7th days of vaginal estrus. In Group 1 rats, surges of the hormones, except estrone, took place in all the 5 cycles. The occurrence of peak hormone levels in each cycle was invariably delayed after transfer of animals to LL. According to regression analyses, the lengths of secretion cycles of LH, FSH, 17 beta-estradiol and progesterone in rats under LL were 100.89, 100.46, 101.14 and 101.06 h, respectively. Elevation of 17 beta-estradiol levels was observed prior to the LH surge, and peaks of progesterone and FSH occurred following it. However, the secretion patterns of these hormones appear to be disrupted with length of exposure to LL. In group 2 rats, the mean concentration of LH during persistent estrus was approximately similar to that on the morning of the days of proestrus of the 4-day cycles of rats placed under an alternating 12-hour light-dark regimen (LD), whereas the mean FSH concentration was continuously low. While the concentrations of 17 beta-estradiol and estrone in persistent-estrous rats were elevated, progesterone levels remained low.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of different hormonal combinations on follicular wave emergence and superovulatory response in sheep.

PubMed

Souza-Fabjan, Joanna Maria Gonçalves; da Rosa, Rômulo Mendonça; Balaro, Mário Felipe Alvarez; Pinto, Pedro Henrique Nicolau; Dos Santos, Gustavo Bervian; Arashiro, Eduardo Kenji Nunes; da Fonseca, Jeferson Ferreira; Ungerfeld, Rodolfo; Brandão, Felipe Zandonadi

2017-11-01

The aim of the present study was to compare hormonal treatments to induce and synchronize follicular wave emergence to improve the results of superovulatory (SOV) treatments in ewes. In Experiment 1 (n = 66), ewes were treated with a progesterone intravaginal implant plus a PGF 2α analogue (group G P4 ), or with the same treatment plus estradiol benzoate (G P4+EB ), a GnRH agonist (G P4+GnRH ), or both, estradiol benzoate and a GnRH agonist (G P4+EB+GnRH ) in a 2 × 2 factorial arrangement. Follicular wave emergence was determined by ultrasound. Follicular wave did not emerge during the studied period in 10 females (one from G P4 , six from G P4+EB and three from G P4+EB+GnRH ). Follicular emergence was less synchronized (P = 0.007) when estradiol was administered (G P4+EB : 103.6 ± 22.0 h), without any interaction with GnRH treatment (G P4+EB+GnRH : 80.1 ± 21.4 h, G P4+GnRH : 52.5 ± 8.7 h, G P4 : 56.6 ± 10.4 h). Estradiol administration delayed the moment of follicular emergence (P = 0.007) and the follicular wave emergence moment in which follicular dominance was achieved (P = 0.009), without interactions between estradiol and GnRH in the moment of follicular wave emergence or dominance. In Experiment 2 (n = 22), two SOV protocols were compared: the best treatment of Experiment 1 (G P4 ) was used to synchronize follicular wave emergence, initiating the SOV treatment 2.5 days later; in the control treatment, SOV treatment started 80 h after a short-term protocol to synchronize ovulation (G control ). The number of corpora lutea (CL) and the evaluation of the collected embryos were performed six days after estrus. Blood samples were collected daily for plasma progesterone determination. Although the number of CL was similar in G control (7.1 ± 1.0) and G P4 (6.9 ± 5.1), the number of structures and viable embryos recovered were greater in G control (P < 0.05). The occurrence of luteal premature regression was significantly greater in G P4 (60%) than in G control (8.3%). The use of GnRH agonist alone did not improve synchronization of follicular wave emergence. When EB was used (alone or associated) follicular wave emergence was less synchronized. The SOV protocol proposed had a similar ovarian response; however, it resulted in less transferable embryos. Copyright © 2017 Elsevier Inc. All rights reserved.

Preparation of TPP-crosslinked chitosan microparticles by spray drying for the controlled delivery of progesterone intended for estrus synchronization in cattle.

PubMed

Helbling, Ignacio M; Busatto, Carlos A; Fioramonti, Silvana A; Pesoa, Juan I; Santiago, Liliana; Estenoz, Diana A; Luna, Julio A

2018-02-20

Planned reproduction in cattle involves regulation of estrous cycle and the use of artificial insemination. Cycle control includes the administration of exogenous progesterone during 5-8 days in a controlled manner allowing females to synchronize their ovulation. Several progesterone delivery systems are commercially available but they have several drawbacks. The aim of the present contribution was to evaluate chitosan microparticles entrapping progesterone as an alternative system. Microparticles were prepared by spray drying. The effect of formulation parameters and experimental conditions on particle features and delivery was studied. A mathematical model to predict progesterone plasma concentration in animals was developed and validated with experimental data. Microparticle size was not affected by formulation parameters but sphericity enhances as Tween 80 content increases and it impairs as TPP content rises. Z potential decreases as phosphate content rises. Particles remain stable in acidic solution but the addition of surfactant is required to stabilize dispersions in neutral medium. Encapsulation efficiencies was 69-75%. In vitro delivery studies showed burst and diffusion-controlled phases, being progesterone released faster at low pH. In addition, delivery extend in cows was affected mainly by particle size and hormone initial content, while the amount injected altered plasma concentration. Theoretical predictions with excellent accuracy were obtained. The mathematical model developed can help to find proper particle features to reach specific delivery rates in the animals. This not only save time, money and effort but also minimized experimentation with animals which is desired from an ethical point of view.

Expression, regulation, and function of drug transporters in cervicovaginal tissues of a mouse model used for microbicide testing.

PubMed

Zhou, Tian; Hu, Minlu; Pearlman, Andrew; Rohan, Lisa C

2016-09-15

P-glycoprotein (P-gp), breast cancer resistance protein (BCRP), and multidrug resistance protein 4 (MRP4) are three efflux transporters that play key roles in the pharmacokinetics of antiretroviral drugs used in the pre-exposure prophylaxis of HIV sexual transmission. In this study, we investigated the expression, regulation, and function of these transporters in cervicovaginal tissues of a mouse model. Expression and regulation were examined using real-time RT-PCR and immunohistochemical staining, in the mouse tissues harvested at estrus and diestrus stages under natural cycling or after hormone synchronization. The three transporters were expressed at moderate to high levels compared to the liver. Transporter proteins were localized in various cell types in different tissue segments. Estrous cycle and exogenous hormone treatment affected transporter mRNA and protein expression, in a tissue- and transporter-dependent manner. Depo-Provera-synchronized mice were dosed vaginally or intraperitoneally with (3)H-TFV, with or without MK571 co-administration, to delineate the function of cervicovaginal Mrp4. Co-administration of MK571 significantly increased the concentration of vaginally-administered TFV in endocervix and vagina. MK571 increased the concentration of intraperitoneally-administered TFV in the cervicovaginal lavage and vagina by several fold. Overall, P-gp, Bcrp, and Mrp4 were positively expressed in mouse cervicovaginal tissues, and their expression can be regulated by the estrous cycle or by exogenous hormones. In this model, the Mrp4 transporter impacted TFV distribution in cervicovaginal tissues. Copyright © 2016. Published by Elsevier Inc.

On gonads and gadflies: the estrus angle.

PubMed

Hillier, Stephen G

2017-06-01

The first sex steroid to be crystallized was the vertebrate ovarian hormone, estrone - a less potent metabolite of 17β-estradiol, which in mammals stimulates the female urge to mate (estrus). The gadfly (Greek oistros ) lent its name to the process of estrus, as an insect that bites and torments in classical Greek mythology. With the purification and crystallization of a moult-inducing steroid (ecdysone) from insects, an interesting parallel emerged between mating and moulting in lower mammals and arthropods. Ecdysterone (potent ecdysone metabolite) has anabolic effects in mammalian muscle cells that can be blocked by selective estrogen receptor antagonists. Insects utilize ecdysteroids in similar ways that vertebrates use estrogens, including stimulation of oocyte growth and maturation. Ecdysteroids also modify precopulatory insect mating behaviour, further reinforcing the gonad-gadfly/mate-moult analogy. © 2017 Society for Endocrinology.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bae, Sijeong; Kwon, Hwang; Yoon, Hyemin

The sine oculis homeobox 1 (SIX1) is a member of the Six gene family. SIX1 is involved in tissue development by regulating proliferation, apoptosis, and differentiation. However, function of SIX1 in the uterus remains unknown. Here, we found that Six1 expression is regulated along the estrous cycle in mouse uterus. Six1 expression was significantly increased at estrus stage and decreased at the rest of stages. SIX1 is detected in the luminal and glandular epithelium of uterine endometrium at the estrus stage. Estrogen injection increased Six1 expression in the ovariectomized mouse uterus, whereas progesterone had no effect on its expression. Estrogenmore » receptor antagonist inhibited estrogen-induced Six1 expression. Our findings imply that SIX1 may play a role as an important regulator to orchestrate the dynamic of uterine endometrium in response to estrogen level during the estrous cycle. These results will give us a better understanding of uterine biology. - Highlights: • Six1 expression is regulated during the estrous cycle in mouse uterus. • Six1 is highly expressed at the estrus stage of estrous cycle. • SIX1 is detected in luminal/glandular epithelium of the uterus at the estrus stage. • Estrogen stimulates Six1 expression in an estrogen receptor-dependent manner.« less

Estrous cycle and food availability affect feeding induced by amygdala 5-HT receptor blockade.

PubMed

Parker, Graham C; Bishop, Christopher; Coscina, Donald V

2002-04-01

We have recently reported that bilateral infusions of the 5-HT receptor antagonist metergoline (MET) into the posterior basolateral amygdala (pBLA) elicit feeding in female rats tested at mid-light cycle. The present study was performed to determine whether (1) testing at two different phases of the estrous cycle, and/or (2) the palatability of the food might modify this effect. Subjects were 18 adult females with bilateral pBLA cannulae. Following familiarization with Froot Loops cereal, a within-subjects design tested all animals for 1- and 2-h food intake under 2 Drug (0.3 nmol MET vs. Vehicle), 2 Estrous Cycle (diestrus vs. estrus) and 2 Food (lab chow vs. Froot Loops) conditions. Rats weighed more at diestrus than at proestrus (P<.05) or estrus (P<.005). Multivariate analyses of variance (MANOVAs) revealed a preference for Froot Loops over lab chow (P<.0001). MET increased feeding regardless of food type (P<.0001). Rats ate more Froot Loops (P<.01), but not lab chow, at diestrus vs. estrus. A three-way interaction (P<.05) showed rats ate more during the first hour in estrus than in diestrus to lab chow but not Froot Loops. These data suggest pBLA MET differentially affects feeding over the estrous cycle depending on the palatability of food available.

Transitional gene expression profiling in ovarian follicle during ovulation in normal-cycle rats.

PubMed

Tsubota, Kenjiro; Kanki, Masayuki; Noto, Takahisa; Shiraki, Katsuhisa; Takeuchi, Ayano; Nakatsuji, Shunji; Seki, Jiro; Oishi, Yuji; Matsumoto, Masahiro; Nakayama, Hiroyuki

2011-06-01

Evaluation of ovarian toxicity requires an understanding of the physiological changes related to the estrous cycle in the ovary. The authors investigated the transitional gene expression profile of ovulatory follicles in rats that show normal estrous cyclicity. Ovaries were collected at 10:00 and 22:00 on the proestrus day and at 10:00 on the estrus day. Ovarian follicles or early corpora lutea were isolated using laser microdissection, and extracted total RNA was analyzed using microarray technology. Clustering analysis revealed four different expression patterns: transient up- or down-regulation only at 22:00 on the proestrus day (pattern 1), up- or down-regulation only at 10:00 on the estrus day (pattern 2), continuous increase at 22:00 on the proestrus day and at 10:00 on the estrus day (pattern 3), and up- or down-regulation at 22:00 on the proestrus day and level maintenance at 10:00 on the estrus day (pattern 4). In addition, these probe sets were functionally categorized in each pattern using the Ingenuity Pathways Analysis database. These data will aid in understanding the physiology of ovulation and may be useful in assessing ovarian toxicity and its mechanism, such as in investigations of chemical-induced ovulatory impairment.

Composite synchronization of three eccentric rotors driven by induction motors in a vibrating system

NASA Astrophysics Data System (ADS)

Kong, Xiangxi; Chen, Changzheng; Wen, Bangchun

2018-03-01

This paper addresses the problem of composite synchronization of three eccentric rotors (ERs) driven by induction motors in a vibrating system. The composite synchronous motion of three ERs is composed of the controlled synchronous motion of two ERs and the self-synchronous motion of the third ER. Combining an adaptive sliding mode control (ASMC) algorithm with a modified master-slave control structure, the controllers are designed to implement controlled synchronous motion of two ERs with zero phase difference. Based on Lyapunov stability theorem and Barbalat's lemma, the stability of the designed controllers is verified. On basis of controlled synchronization of two ERs, self-synchronization of the third ER is introduced to implement composite synchronous motion of three ERs. The feasibility of the proposed composite synchronization method is analyzed by numerical method. The effects of motor and structure parameters on composite synchronous motion are discussed. Experiments on a vibrating test bench driven by three ERs are operated to validate the effectiveness of the proposed composite synchronization method, including a comparison with self-synchronization method.

Approximation methods for the stability analysis of complete synchronization on duplex networks

NASA Astrophysics Data System (ADS)

Han, Wenchen; Yang, Junzhong

2018-01-01

Recently, the synchronization on multi-layer networks has drawn a lot of attention. In this work, we study the stability of the complete synchronization on duplex networks. We investigate effects of coupling function on the complete synchronization on duplex networks. We propose two approximation methods to deal with the stability of the complete synchronization on duplex networks. In the first method, we introduce a modified master stability function and, in the second method, we only take into consideration the contributions of a few most unstable transverse modes to the stability of the complete synchronization. We find that both methods work well for predicting the stability of the complete synchronization for small networks. For large networks, the second method still works pretty well.

Effect of early or late resynchronization based on different methods of pregnancy diagnosis on reproductive performance of dairy cows.

PubMed

Sinedino, L D P; Lima, F S; Bisinotto, R S; Cerri, R L A; Santos, J E P

2014-01-01

The aim of this study was to compare the reproductive performance of dairy cows subjected to early (ER) or late (LR) resynchronization programs after nonpregnancy diagnoses based on either pregnancy-associated glycoproteins (PAG) ELISA or transrectal palpation, respectively. In addition, the accuracy of the PAG ELISA for early pregnancy diagnosis was assessed. Lactating Holstein cows were subjected to a Presynch-Ovsynch protocol with timed artificial insemination (AI) performed between 61 and 74 DIM. On the day of the first postpartum AI, 1,093 cows were blocked by parity and assigned randomly to treatments; however, because of attrition, 452 ER and 520 LR cows were considered for the statistical analyses. After the first postpartum AI, cows were observed daily for signs of estrus and inseminated on the same day of detected estrus. Cows from ER that were not reinseminated in estrus received the first GnRH injection of the Ovsynch protocol for resynchronization 2d before pregnancy diagnosis. On d 28 after the previous AI (d 27 to 34), pregnancy status was determined by PAG ELISA, and nonpregnant cows continued on the Ovsynch protocol for reinsemination. Pregnant cows had pregnancy status reconfirmed on d 46 after AI (d 35 to 52) by transrectal palpation, and those that lost the pregnancies were resynchronized. Cows assigned to LR had pregnancy diagnosed by transrectal palpation on d 46 after AI (d 35 to 52) and nonpregnant cows were resynchronized with the Ovsynch protocol. Blood was sampled on d 28 after AI (d 27 to 34) from cows in both treatments that had not been reinseminated on estrus and again on d 46 after AI (d 35 to 52) for assessment of PAG ELISA to determine the accuracy of the test. Cows were subjected to treatments for 72d after the first insemination. Pregnancy per AI (P/AI) at first postpartum timed AI did not differ between treatments and averaged 28.9%. The proportion of nonpregnant cows that were resynchronized and received timed AI was greater for ER than for LR (30.0 vs. 7.6%). Cows in ER had a shorter interval between inseminations when inseminated following spontaneous estrus (21.7±1.1 vs. 27.8±0.8d) or after timed AI (35.3±1.2 vs. 55.2±1.4d). Nevertheless, the ER did not affect the rate of pregnancy (adjusted hazard ratio=1.23; 95% confidence interval=0.94 to 1.61) or the median days postpartum to pregnancy (ER=132 vs. LR=140). A total of 2,129 PAG ELISA were evaluated. Overall, sensitivity, specificity, and positive and negative predictive values averaged 95.1, 89.0, 90.1, and 94.5%, respectively, and the accuracy was 92.1%. In conclusion, PAG ELISA for early diagnosis of pregnancy had acceptable accuracy, but early resynchronization after nonpregnancy diagnosis with PAG ELISA did not improve the rate of pregnancy or reduce days open in dairy cows continuously observed for estrus. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Birth of cloned mice from vaginal smear cells after somatic cell nuclear transfer.

PubMed

Kuwayama, Hiroki; Tanabe, Yoshiaki; Wakayama, Teruhiko; Kishigami, Satoshi

2017-05-01

Less invasive methods for donor cell collection will facilitate reproduction of wild animals using somatic-cell nuclear transfer. Stages of the estrous cycle in mice have long been studies using somatic cells that can be collected from vaginal walls using cotton tipped swabs in a relatively non-invasive manner. In this study, we examined the feasibility of these cells as sources of nuclei for somatic-cell cloning using nuclear transfer. Estrous cycles generally comprise proestrus, estrus, metestrus, and diestrus stages. In the present experiments, more than 60% of cells were nucleated in vaginal smears from all but the estrus stage. However, after somatic-cell nuclear transfer of cells from proestrus, metestrus, and diestrus stages, 66%, 50%, and 72% of cloned embryos developed to the morula/blastocyst, and cloned female mouse birth rates after embryo transfer were 1.5%, 0.3%, and 1%, respectively. These results show that noninvasively collected vaginal smears contain somatic cells that can be used to clone female mice. Copyright © 2017. Published by Elsevier Inc.

The impact of diet and arginine supplementation on pancreatic mass, digestive enzyme activity, and insulin-containing cell cluster morphology during the estrous cycle in sheep.

PubMed

Keomanivong, F E; Grazul-Bilska, A T; Redmer, D A; Bass, C S; Kaminski, S L; Borowicz, P P; Kirsch, J D; Swanson, K C

2017-04-01

To determine the effect of feed intake and arginine treatment during different stages of the estrous cycle on pancreatic mass, digestive enzyme activity, and histological measurements, ewes (n = 120) were randomly allocated to 1 of 3 dietary groups; control (CON; 2.14-Mcal metabolizable energy/kg), underfed (UF; 0.6 × CON), or overfed (OF; 2 × CON) over 2 yr. Estrus was synchronized using a controlled internal drug release device for 14 d. At controlled internal drug release withdrawal, ewes from each dietary group were assigned to 1 of 2 treatments; Arg (L-Arg HCl, 155-μmol/kg BW) or Sal (approximately 10-mL saline). Treatments were administered 3 times daily via jugular catheter and continued until slaughter on d (day) 5 and 10 of the second estrus cycle (early luteal phase, n = 41 and mid-luteal phase, n = 39; yr 1) and d 15 of the first estrus cycle (late luteal phase, n = 40; yr 2). A blood sample collected from jugular catheters for serum insulin analysis before slaughter. The pancreas was then removed, trimmed of mesentery and fat, weighed, and a sample snap-frozen until enzyme analysis. Additional pancreatic samples were fixed in 10% formalin solution for histological examination of size and distribution of insulin-containing cell clusters. Data were analyzed as a completely randomized design with a factorial arrangement of treatments. Diet, treatment, and diet × treatment were blocked by yr and included in the model with initial BW used as a covariate. Day of the estrous cycle was initially included in the model but later removed as no effects (P > 0.10) were observed for any pancreatic variables tested. Overfed ewes had the greatest (P < 0.001) change in BW, final BW, change in BCS, and final BCS. A diet × treatment interaction was observed for change in BW and final BW (P ≤ 0.004). Overfed and CON had increased (P < 0.001) pancreas weight (g) compared with UF ewes. Protein concentration (g/pancreas) was the lowest (P < 0.001) in UF ewes, whereas protein content (mg/kg BW) was greater (P = 0.03) in UF than OF ewes. Activity of α-amylase (U/g, kU/pancreas, U/kg of BW, and U/g protein) and trypsin (U/pancreas) was greater (P ≤ 0.003) in OF than UF ewes. Serum insulin was the greatest (P < 0.001) in OF ewes. No effects were observed for pancreatic insulin-containing cell clusters. This study demonstrated that plane of nutrition affected several measurements of pancreatic function; however, the dosage of Arg used did not influence pancreatic function. Copyright © 2016 Elsevier Inc. All rights reserved.

Betacarotene supplementation increases ovulation rate without an increment in LH secretion in cyclic goats.

PubMed

Meza-Herrera, Cesar A; Vargas-Beltran, Fermin; Vergara-Hernandez, Hector P; Macias-Cruz, Ulises; Avendaño-Reyes, Leonel; Rodriguez-Martinez, Rafael; Arellano-Rodriguez, Gerardo; Veliz-Deras, Francisco G

2013-03-01

This study aimed to evaluate the effects of betacarotene (BC) supplementation on ovulation rate (OR) and luteinizing hormone (LH) secretion in adult goats during the breeding season. Additionally, total ovarian activity (TOA) comprising the total number of ultrasonographically detectable antral follicles (AF) and corpora lutea (OR) was also assessed. In early October, adult goats [n=22, 3.5 years of age, 7/8 Sannen-Alpine; 26°N, 103°W at 1117m.a.s.l.] were randomly assigned to: (i) BC group (BCG), orally supplemented with 50mg of BC/goat/day [n=10; live weight (LW)=45.9±2.0kg, body condition score (BCS; range: 0-emaciated to 5-obese)=3.0±0.1], and (ii) control group (CONT) [n=12; LW=46.2±2.0kg, BCS=3.0±0.1]. All animals received a basal diet of alfalfa hay, corn silage and corn grain, with free access to water and mineral salts. The whole experimental period spanned 34 days before and 17 days after ovulation. On day 23 of the experiment, estrus was synchronized with progestin-releasing intravaginal sponges; 36h prior to estrus, an intensive blood sampling (every 15min for 6h) was performed to determine mean LH concentrations, pulsatility (LH-PULSE) and area under the curve (LH-AUC) for serial LH concentrations. Afterwards, by the end of the luteal phase (i.e., 17 days after the onset of estrus), an ultrasonographic scanning was performed to evaluate OR and TOA [AF+OR]. The average LW and BCS did not differ (p>0.05) during the experimental period. BC-supplemented goats showed an increase in OR (3.4±0.2 versus 2.8±0.2; p<0.05) and exhibited lower (p<0.05) serum LH concentrations, LH-AUC and LH-PULSE compared to CONT. A positive correlation was recorded between OR and LW (r(2)=0.42, p<0.05) and BCS (r(2)=0.47, p<0.05). In addition, AF (5.0±0.6 versus 3.4±0.6) and TOA (8.4±0.6 versus 6.2±0.6) were greater (p<0.05) in the BC-supplemented group than CONT. Supplementation with BC enhanced ovarian follicular development and ovulation rate in adult female goats under decreased photoperiods through LHRH-independant pathways or direct effects of BC on ovarian function. Copyright © 2013 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Uterosomes: Exosomal cargo during the estrus cycle and interaction with sperm.

PubMed

Martin-DeLeon, Patricia Anastasia

2016-01-01

The term "uterosomes" was first used to classify extracellular membrane vesicles released into the uterine luminal fluid. These extracellular vesicles (EVs), varying in sizes, fit the classification of exosomes and microvesicles on the basis of size, the presence of the CD9 biochemical marker, and lateral orientation of the membrane. Uterosomes appear to be formed by the apocrine pathway, similar to other reproductive EVs. In the murine system, the protein cargo carried by uterosomes includes glycosyl phosphatidylinositol (GPI)-linked and transmembrane proteins and these are hormonally regulated, appearing at high levels during proestrus/estrus and only marginally present at diestrus /metestrus. Uterosomes have been shown to deliver proteins in their cargo to sperm, with a functional impact, and are thought to participate in promoting sperm capacitation. Further studies are warranted, particularly those aimed at identifying the contents of their cargo during the estrus and menstrual cycle and the role they play n sperm maturation.

Evaluation of hormone-free protocols based on the "male effect" for artificial insemination in lactating goats during seasonal anestrus.

PubMed

Pellicer-Rubio, Maria-Teresa; Boissard, Karine; Forgerit, Yvonnick; Pougnard, Jean Louis; Bonné, Jean Luc; Leboeuf, Bernard

2016-03-15

Goat estrous and ovulatory responses to the "male effect" were characterized to determine the time range over which fertile ovulations occur after buck exposure. The results were used to explore the efficacy of different hormone-free artificial insemination (AI) protocols aimed at diminishing the number of inseminations needed to optimize fertility. Adult bucks and does were exposed to artificially long days during winter and then exposed to a natural photoperiod before buck exposure (Day 0). Most goats (>70%) ovulated twice, developing a short cycle followed by a normal cycle over 13 days after buck exposure. Among them, 21% were in estrus at the short cycle and 94% at the normal cycle. This second ovulation occurred within 48 hours of Day 6 and was the target for AI protocols. In protocol A (n = 79), goats were inseminated 12 hours after estrus detection from Day 5 to Day 9. Up to six AI times over 4 days were needed to inseminate goats in estrus. Forty-nine percent of the inseminated goats kidded. In protocol B (n = 145), estrus detection started on Day 5. The earlier (group 1) and later (group 2) buck-marked goats received one single insemination at fixed times on Days 6.5 or 7 and 8, respectively; unmarked goats (group 3) were inseminated along with group 2. In protocol C (n = 153), goats were inseminated twice on Days 6.5 or 7 and 8 without needing to detect estrus. Goats induced to ovulate by hormonal treatment were used as the control (n = 319). Fertility was lower in protocol B than in protocol C and controls (47% vs. 58% and 65% kidding; P ≤ 0.05), whereas this was higher in buck-marked goats than in unmarked ones (64% vs. 33%; P ≤ 0.05). In protocol B, fertility can increase (>60%) when only goats coming into estrus are inseminated. The best kidding rate (∼70%) was achieved when does were inseminated within 24 hours of the LH surge. Protocols involving insemination on Day 7 instead of Day 6.5 led to more goats being inseminated during this favorable time. Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of summer heat environment on body temperature, estrous cycles and blood antioxidant levels in Japanese Black cow.

PubMed

Sakatani, Miki; Balboula, Ahmed Z; Yamanaka, Kenichi; Takahashi, Masashi

2012-05-01

This study investigated the effect of summer heat environment on estrous cycles and blood antioxidant levels in Japanese Black cows. A total of 13 non-lactating Japanese Black cows (summer: 9, winter: 4) were examined. Body temperature was measured rectally and intravaginally using a thermometer and data logger, respectively. Estrous behavior was monitored using a radiotelemetric pedometer that recorded walking activity. Rectal temperatures were higher during summer than winter (P<0.001). There was an acute increase in vaginal temperature at the onset of estrus during winter but such an increase was not observed during summer. Walking activity during estrus decreased dramatically in the summer compared to the winter. Duration of estrous cycle was longer in summer (23.4 days, P<0.05) than winter (21.5 days), and the subsequent rise in progesterone concentrations following estrus tended to be delayed in summer. The level of thiobarbituric acid reactive substances (TBARS) in peripheral blood cells was higher during summer (P<0.05), while the levels of superoixde dismutase (SOD), glutathione peroxidase (GPx) and glutathione were lower (P<0.05). These results indicate that high ambient temperature during summer increases both body temperature and oxidative stress, and also reduces signs of estrus in Japanese Black cows. © 2011 The Authors. Animal Science Journal © 2011 Japanese Society of Animal Science.

Synchronization sampling method based on delta-sigma analog-digital converter for underwater towed array system.

PubMed

Jiang, Jia-Jia; Duan, Fa-Jie; Li, Yan-Chao; Hua, Xiang-Ning

2014-03-01

Synchronization sampling is very important in underwater towed array system where every acquisition node (AN) samples analog signals by its own analog-digital converter (ADC). In this paper, a simple and effective synchronization sampling method is proposed to ensure synchronized operation among different ANs of the underwater towed array system. We first present a master-slave synchronization sampling model, and then design a high accuracy phase-locked loop to synchronize all delta-sigma ADCs to a reference clock. However, when the master-slave synchronization sampling model is used, both the time-delay (TD) of messages traveling along the wired transmission medium and the jitter of the clocks will bring out synchronization sampling error (SSE). Therefore, a simple method is proposed to estimate and compensate the TD of the messages transmission, and then another effective method is presented to overcome the SSE caused by the jitter of the clocks. An experimental system with three ANs is set up, and the related experimental results verify the validity of the synchronization sampling method proposed in this paper.

Synchronization sampling method based on delta-sigma analog-digital converter for underwater towed array system

NASA Astrophysics Data System (ADS)

Jiang, Jia-Jia; Duan, Fa-Jie; Li, Yan-Chao; Hua, Xiang-Ning

2014-03-01

Synchronization sampling is very important in underwater towed array system where every acquisition node (AN) samples analog signals by its own analog-digital converter (ADC). In this paper, a simple and effective synchronization sampling method is proposed to ensure synchronized operation among different ANs of the underwater towed array system. We first present a master-slave synchronization sampling model, and then design a high accuracy phase-locked loop to synchronize all delta-sigma ADCs to a reference clock. However, when the master-slave synchronization sampling model is used, both the time-delay (TD) of messages traveling along the wired transmission medium and the jitter of the clocks will bring out synchronization sampling error (SSE). Therefore, a simple method is proposed to estimate and compensate the TD of the messages transmission, and then another effective method is presented to overcome the SSE caused by the jitter of the clocks. An experimental system with three ANs is set up, and the related experimental results verify the validity of the synchronization sampling method proposed in this paper.

Phasic Contractions of the Mouse Vagina and Cervix at Different Phases of the Estrus Cycle and during Late Pregnancy

PubMed Central

Gravina, Fernanda S.; van Helden, Dirk F.; Kerr, Karen P.; de Oliveira, Ramatis B.; Jobling, Phillip

2014-01-01

Background/Aims The pacemaker mechanisms activating phasic contractions of vaginal and cervical smooth muscle remain poorly understood. Here, we investigate properties of pacemaking in vaginal and cervical tissues by determining whether: 1) functional pacemaking is dependent on the phase of the estrus cycle or pregnancy; 2) pacemaking involves Ca2+ release from sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA) -dependent intracellular Ca2+ stores; and 3) c-Kit and/or vimentin immunoreactive ICs have a role in pacemaking. Methodology/Principal Findings Vaginal and cervical contractions were measured in vitro, as was the distribution of c-Kit and vimentin positive interstitial cells (ICs). Cervical smooth muscle was spontaneously active in estrus and metestrus but quiescent during proestrus and diestrus. Vaginal smooth muscle was normally quiescent but exhibited phasic contractions in the presence of oxytocin or the K+ channel blocker tetraethylammonium (TEA) chloride. Spontaneous contractions in the cervix and TEA-induced phasic contractions in the vagina persisted in the presence of cyclopiazonic acid (CPA), a blocker of the SERCA that refills intracellular SR Ca2+ stores, but were inhibited in low Ca2+ solution or in the presence of nifedipine, an inhibitor of L-type Ca2+channels. ICs were found in small numbers in the mouse cervix but not in the vagina. Conclusions/Significance Cervical smooth muscle strips taken from mice in estrus, metestrus or late pregnancy were generally spontaneously active. Vaginal smooth muscle strips were normally quiescent but could be induced to exhibit phasic contractions independent on phase of the estrus cycle or late pregnancy. Spontaneous cervical or TEA-induced vaginal phasic contractions were not mediated by ICs or intracellular Ca2+ stores. Given that vaginal smooth muscle is normally quiescent then it is likely that increases in hormones such as oxytocin, as might occur through sexual stimulation, enhance the effectiveness of such pacemaking until phasic contractile activity emerges. PMID:25337931

Phasic contractions of the mouse vagina and cervix at different phases of the estrus cycle and during late pregnancy.

PubMed

Gravina, Fernanda S; van Helden, Dirk F; Kerr, Karen P; de Oliveira, Ramatis B; Jobling, Phillip

2014-01-01

The pacemaker mechanisms activating phasic contractions of vaginal and cervical smooth muscle remain poorly understood. Here, we investigate properties of pacemaking in vaginal and cervical tissues by determining whether: 1) functional pacemaking is dependent on the phase of the estrus cycle or pregnancy; 2) pacemaking involves Ca2+ release from sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA) -dependent intracellular Ca2+ stores; and 3) c-Kit and/or vimentin immunoreactive ICs have a role in pacemaking. Vaginal and cervical contractions were measured in vitro, as was the distribution of c-Kit and vimentin positive interstitial cells (ICs). Cervical smooth muscle was spontaneously active in estrus and metestrus but quiescent during proestrus and diestrus. Vaginal smooth muscle was normally quiescent but exhibited phasic contractions in the presence of oxytocin or the K+ channel blocker tetraethylammonium (TEA) chloride. Spontaneous contractions in the cervix and TEA-induced phasic contractions in the vagina persisted in the presence of cyclopiazonic acid (CPA), a blocker of the SERCA that refills intracellular SR Ca2+ stores, but were inhibited in low Ca2+ solution or in the presence of nifedipine, an inhibitor of L-type Ca2+channels. ICs were found in small numbers in the mouse cervix but not in the vagina. Cervical smooth muscle strips taken from mice in estrus, metestrus or late pregnancy were generally spontaneously active. Vaginal smooth muscle strips were normally quiescent but could be induced to exhibit phasic contractions independent on phase of the estrus cycle or late pregnancy. Spontaneous cervical or TEA-induced vaginal phasic contractions were not mediated by ICs or intracellular Ca2+ stores. Given that vaginal smooth muscle is normally quiescent then it is likely that increases in hormones such as oxytocin, as might occur through sexual stimulation, enhance the effectiveness of such pacemaking until phasic contractile activity emerges.

Synchronous Control Method and Realization of Automated Pharmacy Elevator

NASA Astrophysics Data System (ADS)

Liu, Xiang-Quan

Firstly, the control method of elevator's synchronous motion is provided, the synchronous control structure of double servo motor based on PMAC is accomplished. Secondly, synchronous control program of elevator is implemented by using PMAC linear interpolation motion model and position error compensation method. Finally, the PID parameters of servo motor were adjusted. The experiment proves the control method has high stability and reliability.

[Levels of total lipids, cholesterol and progesterone during estrus synchronization and pregnancy in sheep].

PubMed

Krajnicáková, M; Bekeová, E; Hendrichovský, V; Maracek, I

1993-01-01

Our investigations were concerned with dynamic changes in total lipids (CL), cholesterol (CHOL) and progesterone (P4) in blood serum of sheep in the period of oestrus synchronization treatment and during mating and gravidity. Our experiment was carried out using 10 animals housed under the conditions of productive rearing. Blood samples were taken from v. jugularis on day of swab application (day 0) and on days 3 and 7 of the action of Agelin vaginal swabs, on day of insemination, and on days 7, 14, 17 and in the 2nd, 3rd and 4th month of gravidity. Blood serum was used to determine total lipids and cholesterol by means of Bio-Lachema tests, and P4 concentrations employing RIA-test-Prog kits (URVJT, Kosice). A statistically significant decrease in concentrations of total lipids (Fig. 1, Tab. I) in sheep blood serum was recorded on day of insemination (P < 0.05) compared to day 0, with the value 1.59 +/- 0.31 g/l of serum, and in the 3rd month of gravidity (P < 0.01), at concentrations 1.36 +/- 0.38 g/l of serum. The determined decrease in their values in the mentioned period can be modulated by the mutually changing ratio of steroid hormones or by inhibition of synthesis of lipoproteins responsible for changes in total plasma lipids. Changes in cholesterol concentrations (Fig. 2, Tab. I) during the introduction of swabs were insignificant and ranged from 1.60 +/- 0.42 to 1.73 +/- 0.33 mmol/l of serum. An insignificant increase in cholesterol concentrations (P < 0.05), with its highest levels 1.98 +/- 0.43 mmol/l of serum, was recorded in the 3rd month of gravidity.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of Fertility on Gene Expression and Function of the Bovine Endometrium

PubMed Central

Minten, Megan A.; Bilby, Todd R.; Bruno, Ralph G. S.; Allen, Carolyn C.; Madsen, Crystal A.; Wang, Zeping; Sawyer, Jason E.; Tibary, Ahmed; Neibergs, Holly L.; Geary, Thomas W.; Bauersachs, Stefan; Spencer, Thomas E.

2013-01-01

Infertility and subfertility are important and pervasive reproductive problems in both domestic animals and humans. The majority of embryonic loss occurs during the first three weeks of pregnancy in cattle and women due, in part, to inadequate endometrial receptivity for support of embryo implantation. To identify heifers of contrasting fertility, serial rounds of artificial insemination (AI) were conducted in 201 synchronized crossbred beef heifers. The heifers were then fertility classified based on number of pregnancies detected on day 35 in four AI opportunities. Heifers, classified as having high fertility, subfertility or infertility, were selected for further study. The fertility-classified heifers were superovulated and flushed, and the recovered embryos were graded and then transferred to synchronized recipients. Quantity of embryos recovered per flush, embryo quality, and subsequent recipient pregnancy rates did not differ by fertility classification. Two in vivo-produced bovine embryos (stage 4 or 5, grade 1 or 2) were then transferred into each heifer on day 7 post-estrus. Pregnancy rates were greater in high fertility than lower fertility heifers when heifers were used as embryo recipients. The reproductive tracts of the classified heifers were obtained on day 14 of the estrous cycle. No obvious morphological differences in reproductive tract structures and histology of the uterus were observed in the heifers. Microarray analysis revealed differences in the endometrial transcriptome based on fertility classification. A genome-wide association study, based on SNP genotyping, detected 7 moderate associations with fertility across 6 different chromosomes. Collectively, these studies support the idea that innate differences in uterine function underlie fertility and early pregnancy loss in ruminants. Cattle with defined early pregnancy success or loss is useful to elucidate the complex biological and genetic mechanisms governing endometrial receptivity and uterine competency for pregnancy. PMID:23940519

Accessory corpora lutea formation in pregnant Hokkaido sika deer (Cervus nippon yesoensis) investigated by examination of ovarian dynamics and steroid hormone concentrations.

PubMed

Yanagawa, Yojiro; Matsuura, Yukiko; Suzuki, Masatsugu; Saga, Shin-Ichi; Okuyama, Hideto; Fukui, Daisuke; Bando, Gen; Nagano, Masashi; Katagiri, Seiji; Takahashi, Yoshiyuki; Tsubota, Toshio

2015-01-01

Generally, sika deer conceive a single fetus, but approximately 80% of pregnant females have two corpora lutea (CLs). The function of the accessory CL (ACL) is unknown; moreover, the process of ACL formation is unclear, and understanding this is necessary to know its role. To elucidate the process of ACL formation, the ovarian dynamics of six adult Hokkaido sika deer females were examined ultrasonographically together with peripheral estradiol-17β and progesterone concentrations. ACLs formed in three females that conceived at the first estrus of the breeding season, but not in those females that conceived at the second estrus. After copulation, postconception ovulation of the dominant follicle of the first wave is induced by an increase in estradiol-17β, which leads to formation of an ACL. A relatively low concentration of progesterone after the first estrus of the breeding season is considered to be responsible for the increase in estradiol-17β after copulation.

Accessory corpora lutea formation in pregnant Hokkaido sika deer (Cervus nippon yesoensis) investigated by examination of ovarian dynamics and steroid hormone concentrations

PubMed Central

YANAGAWA, Yojiro; MATSUURA, Yukiko; SUZUKI, Masatsugu; SAGA, Shin-ichi; OKUYAMA, Hideto; FUKUI, Daisuke; BANDO, Gen; NAGANO, Masashi; KATAGIRI, Seiji; TAKAHASHI, Yoshiyuki; TSUBOTA, Toshio

2014-01-01

Generally, sika deer conceive a single fetus, but approximately 80% of pregnant females have two corpora lutea (CLs). The function of the accessory CL (ACL) is unknown; moreover, the process of ACL formation is unclear, and understanding this is necessary to know its role. To elucidate the process of ACL formation, the ovarian dynamics of six adult Hokkaido sika deer females were examined ultrasonographically together with peripheral estradiol-17β and progesterone concentrations. ACLs formed in three females that conceived at the first estrus of the breeding season, but not in those females that conceived at the second estrus. After copulation, postconception ovulation of the dominant follicle of the first wave is induced by an increase in estradiol-17β, which leads to formation of an ACL. A relatively low concentration of progesterone after the first estrus of the breeding season is considered to be responsible for the increase in estradiol-17β after copulation. PMID:25482110

Synchronization in node of complex networks consist of complex chaotic system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wei, Qiang, E-mail: qiangweibeihua@163.com; Digital Images Processing Institute of Beihua University, BeiHua University, Jilin, 132011, Jilin; Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian, 116024

2014-07-15

A new synchronization method is investigated for node of complex networks consists of complex chaotic system. When complex networks realize synchronization, different component of complex state variable synchronize up to different scaling complex function by a designed complex feedback controller. This paper change synchronization scaling function from real field to complex field for synchronization in node of complex networks with complex chaotic system. Synchronization in constant delay and time-varying coupling delay complex networks are investigated, respectively. Numerical simulations are provided to show the effectiveness of the proposed method.

The effects of ceftriaxone on cue-primed reinstatement of cocaine-seeking in male and female rats: estrous cycle effects on behavior and protein expression in the nucleus accumbens

PubMed Central

Hamor, Peter U.; Schwendt, Marek; Knackstedt, Lori A.

2018-01-01

Rationale Effective pharmacological treatments to prevent cocaine relapse remain elusive. In male rats, ceftriaxone attenuates the reinstatement of cocaine-seeking while increasing glutamate transporter-1 (GLT-1) and xCT expression in the nucleus accumbens core (NAc). Despite reported sex differences in cocaine relapse, these effects have not yet been confirmed in female rats. Objective We investigated the effects of ceftriaxone on cue-primed reinstatement and cocaine-induced alterations in glutamatergic proteins in the NAc of female rats. Potential interactions between estrous phase and treatment were also assessed. Method Male and female rats self-administered cocaine in the presence of discrete cues for 12 days, followed by 2–3 weeks of extinction. Ceftriaxone or vehicle was administered daily for a minimum of 6 days immediately preceding a cue-primed reinstatement test. Results Total cocaine intake was greater in females than in males, but reinstatement behavior was similar. Ceftriaxone attenuated reinstatement in both sexes and was accompanied by increased expression of GLT-1a and xCT in the NAc. However, ceftriaxone attenuated reinstatement only when females were tested during met-, di-, and proestrus phases and not during estrus. A significant increase in AMPA receptor subunit GluA1 surface expression was also observed during estrus, potentially influencing reinstatement. Conclusion These findings extend the beneficial effects of ceftriaxone on persistent cocaine-seeking from males to females, increasing its potential as a pharmacological treatment for preventing relapse. The effects of estrus on GluA1 expression and reinstatement observed here indicate that females may need additional interventions during some phases of the menstrual cycle. PMID:29197981

Differences in Retinal Structure and Function between Aging Male and Female Sprague-Dawley Rats are Strongly Influenced by the Estrus Cycle

PubMed Central

Chaychi, Samaneh; Polosa, Anna; Lachapelle, Pierre

2015-01-01

Purpose Biological sex and age are considered as two important factors that may influence the function and structure of the retina, an effect that might be governed by sexual hormones such as estrogen. The purpose of this study was to delineate the influence that biological sex and age exert on the retinal function and structure of rodents and also clarify the effect that the estrus cycle might exert on the retinal function of female rats. Method The retinal function of 50 normal male and female albino Sprague-Dawley (SD) rats was investigated with the electroretinogram (ERG) at postnatal day (P) 30, 60, 100, 200, and 300 (n = 5–6 male and female rats/age). Following the ERG recording sessions, retinal histology was performed in both sexes. In parallel, the retinal function of premenopausal and menopausal female rats aged P540 were also compared. Results Sex and age-related changes in retinal structure and function were observed in our animal model. However, irrespective of age, no significant difference was observed in ERG and retinal histology obtained from male and female rats. Notwithstanding the above we did however notice that between P60 and P200 there was a gradual increase in ERG amplitudes of female rats compared to males. Furthermore, the ERG of premenopausal female rats aged 18 months old (P540) was larger compared to age-matched menopausal female rats as well as that of male rats. Conclusion Our results showed that biological sex and age can influence the retinal function and structure of albino SD rats. Furthermore, we showed that cycled female rats have better retinal function compared to the menopausal female rats suggesting a beneficial effect of the estrus cycle on the retinal function. PMID:26317201

Effect of P.G. 600 on rebreeding performance in sows limit-fed during lactation.

PubMed

Estienne, Mark J; Harper, Allen F; Horsley, B Ryan

2006-03-01

The objective was to determine whether treatment with 400 IU PMSG and 200 IU hCG (P.G. 600; Intervet America, Inc., Millsboro, DE, USA) at weaning improved rebreeding performance in sows that were limit-fed during lactation. Crossbred sows were allowed ad libitum access to feed or were limited to 3.2 kg of feed/day during an 18-day lactation. At weaning, limit-fed sows received im treatment with P.G. 600 (n = 16) or saline (n = 19) and ad libitum-fed sows received saline (n = 18). The percentage of sows in estrus by day 7 post-weaning was greater (p<0.05), and the weaning-to-estrus interval was shorter (p<0.05), for ad libitum-fed sows compared to limit-fed, saline-treated sows, with limit-fed, P.G. 600-treated sows having intermediate values that were not different from the other two groups. The percentage of sows pregnant and the numbers of corpora lutea and embryos at day 30 post-mating were not different (p>0.1) among groups. In summary, low feed intake during lactation decreased the percentage of sows that displayed estrus within 7 days after weaning and increased the weaning-to-estrus interval. These effects were at least partially remediated by gonadotropin treatment. Pregnancy rate, and litter size at day 30 of gestation, were similar for ad libitum- and limit-fed sows and not affected by P.G. 600 treatment in limit-fed sows.

[Profile of sulphated glycosaminoglycans content in the murine uterus during the different phases of the estrous cycle].

PubMed

Gomes, Regina Célia Teixeira; Simões, Ricardo Santos; Soares, José Maria; Nader, Helena Bonciani; Simões, Manuel de Jesus; Baracat, Edmund C

2007-01-01

Identification and quantitation of sulphated glycosaminoglycans (GAGs) in the uterus of female mice during the estrous cycle. Four groups (n = 10 each) of virgin, 100-day old female mice were assembled according to the estrous cycle phase: proestrus, estrus, metaestrus and diestrus. Samples of the median portion of uterine horns were processed for light microscopy examination (H/E and Alcian blue + PAS). The GAGs were extracted and characterized by agarose gel electrophoresis. Data were analyzed by the unpaired Student's t-test. At light microscopy GAGs appear in all layers of the uterus, especially in the endometrium, between collagen fibers, in the basal membrane and around fibroblasts. Biochemical analyses disclosed presence of dermatan sulphate (DS), chondroitin sulphate (CS and heparan sulphate (HS) during all estral cycle phases. There was no clear electrophoretic separation between DS and CS, thus these two GAGs were considered together (DS+CS) (proestrus = 0.854 +/- 0.192; estrus = 1.073 +/- 0.254; metaestrus = 1.003 +/- 0.255; diestrus = 0.632 +/- 0.443 microg/mg). HS was as follows: proestrus = 0.092 +/- 0.097; estrus = 0.180 +/- 0.141; metaestrus = 0.091 +/- 0.046; diestrus = 0.233 +/- 0.147 microg/mg. The uterine content of DS+CS peaked at estrus (estrogenic action) and that of HS at diestrus (progestagen action). Due to a constant turnover process, there are definite alterations in the uterine profile of GAGs content during the estrous cycle in mice, which may be modulated by female sex hormones.

Potential of connected devices to optimize cattle reproduction.

PubMed

Saint-Dizier, Marie; Chastant-Maillard, Sylvie

2018-05-01

Estrus and calving are two major events of reproduction that benefit from connected devices because of their crucial importance in herd economics and the amount of time required for their detection. The objectives of this review are to: 1) provide an update on performances reached by sensor systems to detect estrus and calving time; 2) discuss current economic issues related to connected devices for the management of cattle reproduction; 3) propose perspectives for these devices. The main physiological parameters monitored separately or in combination by connected devices are the cow activity, body temperature and rumination or eating behavior. The combination of several indicators in one sensor may maximize the performances of estrus and calving detection. An effort remains to be made for the prediction of calvings that will require human assistance (dystocia). The main reasons to invest in connected devices are to optimize herd reproductive performances and reduce labor on farm. The economic benefit was evaluated for estrus detection and depends on the initial herd performances, herd size, labor cost and price of the equipment. Major issues associated with the use of automated sensor systems are the weight of financial investment, the lack of economic analysis and limited skills of the users to manage associated technologies. In the near future, connected devices may allow a precise phenotyping of reproductive and health traits on animals and could help to improve animal welfare and public perception of animal production. Copyright © 2017 Elsevier Inc. All rights reserved.

Factors affecting retention of early pregnancy in dairy cattle.

PubMed

Starbuck, Melanie J; Dailey, Robert A; Inskeep, E Keith

2004-08-01

Potential factors affecting retention of pregnancy during weeks 5-9 of gestation were studied in dairy cows and heifers (N = 211) on two farms. Cows were examined by ultrasonography for presence of a viable embryo, and sizes of the corpus luteum (CL) and of follicles > or = 5mm were recorded. Blood samples were taken at each examination and assayed for progesterone and estradiol. Overall pregnancy loss was 11.4%. Cows with two CL did not have greater concentrations of progesterone than cows with one CL and they retained fewer pregnancies (P < 0.01; 73% versus 91%). Pregnancy retention was associated positively with concentrations of progesterone and estradiol during week 5 (P < 0.05). Embryos that were lost apparently died before CL regression. Retention of pregnancy declined in cows with high body condition and as age of the cow increased. Pregnancy retention was lower in cows bred to one of four frequently-used service sires (P < 0.05). Days postpartum, milk production, parity, service number, inseminator, synchronization of estrus, diameter of follicles and size of CL did not affect pregnancy retention. In conclusion, retention of pregnancy during placentation varied with concentrations of progesterone and estradiol, age of cow, body condition and service sire.

Macronuclear Cytology of Synchronized Tetrahymena pyriformis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cameron, I. L.; Padilla, G. M.; Miller, Jr., O. L.

1966-05-01

Elliott, Kennedy and Bak ('62) and Elliott ('63) followed fine structural changes in macronuclei of Tetrahymena pyriformis which were synchronized by the heat shock method of Scherbaum and Zeuthen ('54). Using Elliott's morphological descriptions as a basis, we designed our investigations with two main objectives: First, to again study the. morphological changes which occur in the macronucleus of Tetrahymena synchronized by the heat shock method. The second objective was to compare these observations with Tetrahymena synchronized by an alternate method recently reported by Padilla and Cameron ('64). Therefore, we were able to compare the results from two different synchronization methodsmore » and to contrast these findings with the macronuclear cytology of Tetrahymena taken from a logarithmically growing culture. Comparison of cells treated in these three different ways enables us to evaluate the two different synchronization methods and to gain more information on the structural changes taking place in the macronucleus of Tetrahymena as a function of the cell cycle. Our observations were confined primarily to nucleolar morphology. The results indicate that cells synchronized by the Padilla and Cameron method more closely resemble logarithmically growing Tetrahymena in the macronuclear structure than do cells obtained by the Scherbaum and·Zeuthen synchronization method. .« less

Gait-Event-Based Synchronization Method for Gait Rehabilitation Robots via a Bioinspired Adaptive Oscillator.

PubMed

Chen, Gong; Qi, Peng; Guo, Zhao; Yu, Haoyong

2017-06-01

In the field of gait rehabilitation robotics, achieving human-robot synchronization is very important. In this paper, a novel human-robot synchronization method using gait event information is proposed. This method includes two steps. First, seven gait events in one gait cycle are detected in real time with a hidden Markov model; second, an adaptive oscillator is utilized to estimate the stride percentage of human gait using any one of the gait events. Synchronous reference trajectories for the robot are then generated with the estimated stride percentage. This method is based on a bioinspired adaptive oscillator, which is a mathematical tool, first proposed to explain the phenomenon of synchronous flashing among fireflies. The proposed synchronization method is implemented in a portable knee-ankle-foot robot and tested in 15 healthy subjects. This method has the advantages of simple structure, flexible selection of gait events, and fast adaptation. Gait event is the only information needed, and hence the performance of synchronization holds when an abnormal gait pattern is involved. The results of the experiments reveal that our approach is efficient in achieving human-robot synchronization and feasible for rehabilitation robotics application.

Statistically rigorous calculations do not support common input and long-term synchronization of motor-unit firings

PubMed Central

Kline, Joshua C.

2014-01-01

Over the past four decades, various methods have been implemented to measure synchronization of motor-unit firings. In this work, we provide evidence that prior reports of the existence of universal common inputs to all motoneurons and the presence of long-term synchronization are misleading, because they did not use sufficiently rigorous statistical tests to detect synchronization. We developed a statistically based method (SigMax) for computing synchronization and tested it with data from 17,736 motor-unit pairs containing 1,035,225 firing instances from the first dorsal interosseous and vastus lateralis muscles—a data set one order of magnitude greater than that reported in previous studies. Only firing data, obtained from surface electromyographic signal decomposition with >95% accuracy, were used in the study. The data were not subjectively selected in any manner. Because of the size of our data set and the statistical rigor inherent to SigMax, we have confidence that the synchronization values that we calculated provide an improved estimate of physiologically driven synchronization. Compared with three other commonly used techniques, ours revealed three types of discrepancies that result from failing to use sufficient statistical tests necessary to detect synchronization. 1) On average, the z-score method falsely detected synchronization at 16 separate latencies in each motor-unit pair. 2) The cumulative sum method missed one out of every four synchronization identifications found by SigMax. 3) The common input assumption method identified synchronization from 100% of motor-unit pairs studied. SigMax revealed that only 50% of motor-unit pairs actually manifested synchronization. PMID:25210152

Note: A phase synchronization photography method for AC discharge.

PubMed

Wu, Zhicheng; Zhang, Qiaogen; Ma, Jingtan; Pang, Lei

2018-05-01

To research discharge physics under AC voltage, a phase synchronization photography method is presented. By using a permanent-magnet synchronous motor to drive a photography mask synchronized with a discharge power supply, discharge images in a specific phase window can be recorded. Some examples of discharges photographed by this method, including the corona discharge in SF 6 and the corona discharge along the air/epoxy surface, demonstrate the feasibility of this method. Therefore, this method provides an effective tool for discharge physics researchers.

Note: A phase synchronization photography method for AC discharge

NASA Astrophysics Data System (ADS)

Wu, Zhicheng; Zhang, Qiaogen; Ma, Jingtan; Pang, Lei

2018-05-01

To research discharge physics under AC voltage, a phase synchronization photography method is presented. By using a permanent-magnet synchronous motor to drive a photography mask synchronized with a discharge power supply, discharge images in a specific phase window can be recorded. Some examples of discharges photographed by this method, including the corona discharge in SF6 and the corona discharge along the air/epoxy surface, demonstrate the feasibility of this method. Therefore, this method provides an effective tool for discharge physics researchers.

Synchronization of Chaotic Systems without Direct Connections Using Reinforcement Learning

NASA Astrophysics Data System (ADS)

Sato, Norihisa; Adachi, Masaharu

In this paper, we propose a control method for the synchronization of chaotic systems that does not require the systems to be connected, unlike existing methods such as that proposed by Pecora and Carroll in 1990. The method is based on the reinforcement learning algorithm. We apply our method to two discrete-time chaotic systems with mismatched parameters and achieve M step delay synchronization. Moreover, we extend the proposed method to the synchronization of continuous-time chaotic systems.

Effect of progesterone supplementation in the first week post conception on embryo survival in beef heifers.

PubMed

Beltman, M E; Lonergan, P; Diskin, M G; Roche, J F; Crowe, M A

2009-04-15

Progesterone is essential for establishment and maintenance of pregnancy in mammals. The objective of this study was to examine the effect of elevating progesterone during the different physiological stages of early embryo development on embryo survival. Estrus was synchronized in cross-bred beef heifers (n=197, approximately 2-years old) and they were inseminated 12-18h after estrus onset (=Day 0). Inseminated heifers were randomly assigned to 1 of 3 treatments: (1) Control, n=69; (2) progesterone supplementation using a Controlled Internal Drug Release Device (CIDR) from Day 3 to 6.5, n=64; or (3) progesterone supplementation using a CIDR from Day 4.5 to 8, n=64. Body condition (BCS) and locomotion scores (scale of 1-5) were recorded for all animals. Animals with a locomotion score >/=4 (very lame) were excluded. Embryo survival rate was determined at slaughter on Day 25. Conceptus length and weight were recorded and the corpus luteum (CL) of all pregnant animals was dissected and weighed. Supplementation with exogenous progesterone increased (P<0.05) peripheral progesterone concentrations, but did not affect embryo survival rate compared with controls. Mean CL weight, conceptus length and conceptus weight were not different between treatments. There was a positive relationship (P<0.04) between the increase in progesterone concentrations from Days 3 to 6.5 and embryo survival rate in treated heifers and a similar trend existed between the increase from Days 4.5 to 8 (P<0.06). There was also a positive relationship (P<0.05) between the progesterone concentration on Day 6.5 and the embryo survival rate in treated heifers. A direct correlation was seen between locomotion score and embryo survival rate, with higher (P<0.05) early embryo survival rates in heifers with a lower locomotion score. In conclusion, supplementation with progesterone at different stages of early embryo development increased peripheral progesterone concentration and resulted in a positive association between changes in progesterone concentration during the early luteal phase and embryo survival rate. Supplementation with progesterone had no effect on either CL weight or conceptus size in pregnant animals. Lameness had a significant negative effect on early embryo survival.

Effect of long-term and short-term progestagen treatment on follicular development and pregnancy rate in cyclic ewes.

PubMed

Viñoles, C; Forsberg, M; Banchero, G; Rubianes, E

2001-03-01

The aim of this study was to evaluate the effect of the length of a progestagen treatment (12 d vs. 6 d) on follicular dynamics, estrus synchronization and pregnancy rate using medroxyprogesterone acetate (MAP) with or without an eCG dose at the end of MAP treatment. One hundred sixty Polwarth ewes were divided into four equal groups: long-term treated (LT, n=40); short-term treated (ST, n=40); long-term treated plus eCG (LTeCG, n=40); and short-term treated plus eCG (STeCG, n=40). Five ewes of each group were separated to undergo daily transrectal ultrasonography, and blood samples were taken for hormone determination. Until 96 h after sponge withdrawal the number of ewes in estrus was higher in both long-term-treated groups than in both short-term-treated groups but at the end of the observational period (144 h) no significant differences were found among groups. The pregnancy rate was higher in the ST group (87%) than in the other groups (LT, 63%; LTeCG, 67%; and STeCG, 58%; P< or =0.03). The ovulatory follicle emerged before sponge withdrawal in long-term-treated ewes (-3.8+/-0.4 d and -2.2+/-0.8 d for LT and LTeCG, respectively), whereas in short-term-treated ewes it emerges around sponge removal (0.4+/-1.1 d and 0.5+/-0.5 d for ST and STeCG, respectively; P< or =0.01). The ovulatory follicle in the LT group had a longer lifespan and attained a larger (P< or =0.05) maximum diameter than in the ST group. We conclude: a) that the lower pregnancy rate observed after long-term progestagen treatment was related to a slower follicular turnover that promoted the ovulation of persistent dominant follicles; (b) that short-term treatment resulted in a higher pregnancy rate probably due to the ovulation of newly recruited growing follicles; and (c) treatment with eCG had no advantage in association with long-term treatment and had a deleterious effect in combination with short-term treatment with MAP.

Effects of rapid temperature fluctuations prior to breeding on reproductive efficiency in replacement gilts.

PubMed

Johnson, J S; Martin, K L; Pohler, K G; Stewart, K R

2016-10-01

Rapidly cooling pigs after heat stress (HS) results in a pathophysiological condition, and because rapid temperature fluctuations may be associated with reduced reproductive success in sows, it lends itself to the hypothesis that these conditions may be linked. Objectives were to determine the effects of rapid cooling on thermal response and future reproductive success in pigs. Thirty-six replacement gilts (137.8±0.9kg BW) were estrus synchronized and then 14.1±0.4 d after estrus confirmation, pigs were exposed to thermoneutral conditions (TN; n=12; 19.7±0.9°C) for 6h, or HS (36.3±0.5°C) for 3h, followed by 3h of rapid cooling (HSRC; n=12; immediate TN exposure and water dousing) or gradual cooling (HSGC; n=12; gradual decrease to TN conditions) repeated over 2 d. Vaginal (T V ) and gastrointestinal tract temperatures (T GI ) were obtained every 15min, and blood was collected on d 1 and d 2 during the HS and recovery periods at 180 and 60min, respectively. Pigs were bred 8.3±0.8 d after thermal treatments over 2 d. Reproductive tracts were collected and total fetus number and viability were recorded 28.0±0.8 d after insemination. HS increased T V and T GI (P=0.01; 0.98°C) in HSRC and HSGC compared to TN pigs. During recovery, T V was reduced from 15 to 105min (P=0.01; 0.33°C) in HSRC compared to HSGC pigs, but no overall differences in T GI were detected (P<0.05; 39.67°C). Rapid cooling increased (P<0.05) TNFα compared to HSGC and TN pigs during recovery-d 1 (55.2%), HS-d 2 (35.1%), and recovery-d 2 (64.9%). Viable fetuses tended to be reduced (P=0.08; 10.5%) and moribund fetuses tended to be increased (P=0.09; 159.3%) in HSRC compared to HSGC and TN pigs. In summary, rapid cooling prior to breeding may contribute to reduced fetal viability and reproductive success in pigs. Published by Elsevier Ltd.

Effects of exogenous melatonin on in vivo embryo viability and oocyte competence of undernourished ewes after weaning during the seasonal anestrus.

PubMed

Vázquez, M I; Abecia, J A; Forcada, F; Casao, A

2010-09-01

This study investigated the effects of exogenous melatonin on embryo viability and oocyte competence in post-partum undernourished ewes during the seasonal anestrus. At parturition (mid-Feb), 36 adult Rasa Aragonesa ewes were assigned to one of two groups: treated (+MEL) or not treated (-MEL) with a subcutaneous implant of melatonin (Melovine(R), CEVA) on the day of lambing. After 45 d of suckling, lambs were weaned, ewes were synchronized using intravaginal pessaries, and fed to provide 1.5x (Control, C) or 0.5x (Low, L) times daily maintenance requirements. Thus, ewes were divided into four groups: C-MEL, C+MEL, L-MEL, and L+MEL. At estrus (Day=0), ewes were mated. At Day 5 after estrus, embryos were recovered by mid-ventral laparotomy and classified based on their developmental stage and morphology. After embryo collection, ovaries were recovered and oocytes were classified and selected for use in in vitro fertilization (IVF). Neither diet nor melatonin treatment had a significant effect on ovulation rate and on the number of ova recovered per ewe. Melatonin treatment significantly improved the number of fertilized embryos/corpus luteum (CL) (-MEL: 0.35 +/- 0.1, +MEL: 0.62 +/- 0.1; P = 0.08), number of viable embryos/CL (-MEL: 0.23 +/- 0.1, +MEL: 0.62 +/- 0.1; P < 0.01), viability rate (-MEL: 46.6%, +MEL: 83.9%; P < 0.05), and pregnancy rate (-MEL: 26.3%, +MEL: 76.5%; P < 0.05). In particular, exogenous melatonin improved embryo viability in undernourished ewes (L-MEL: 40%, L+MEL: 100%, P < 0.01). Neither nutrition nor exogenous melatonin treatments significantly influenced the competence of oocytes during IVF. Treatment groups did not differ significantly in the number of healthy oocytes used for IVF, number of cleaved embryos, or number of blastocysts and, consequently, the groups had similar cleavage and blastocyst rates. In conclusion, melatonin treatments improved ovine embryo viability during anestrus, particularly in undernourished post-partum ewes, although the effects of melatonin did not appear to be mediated at the oocyte competence level. Copyright 2010 Elsevier Inc. All rights reserved.

Hormonal treatment before and after artificial insemination differentially improves fertility in subpopulations of dairy cows during the summer and autumn.

PubMed

Friedman, E; Voet, H; Reznikov, D; Wolfenson, D; Roth, Z

2014-12-01

Reduced conception rate (CR) during the hot summer and subsequent autumn is a well-documented phenomenon. Intensive use of cooling systems can improve summer and autumn reproductive performance, but is unable to increase CR to winter and spring levels. We examined whether combined hormonal treatments--to increase follicular turnover before artificial insemination (AI) and progesterone supplementation post-AI--might improve fertility of cooled cows during the summer and autumn. The experiment was conducted from July to November in 3 commercial herds in Israel and included 707 Holstein cows at 50 to 60 d in milk (DIM). Cows were hormonally treated to induce 2 consecutive 9-d cycles, with GnRH administration followed by PGF2α injection 7 d later, followed by an intravaginal insert containing progesterone on d 5 ± 1 post-AI for 14 d. Both untreated controls (n=376) and treated cows (n=331) were inseminated following estrus, and pregnancy was determined by palpation 42 to 50 d post-AI. First-AI CR data revealed a positive interaction between treatment and cows previously diagnosed with postpartum uterine disease [odds ratio (OR) 2.24]. Interaction between treatment and low body condition score tended to increase the probability of first-AI CR (OR 1.95) and increased pregnancy rate at 90 DIM (OR 2.50) and at 120 DIM (OR 1.77). Low milk production increased the probability of being detected in estrus at the end of synchronization within treated cows (OR 1.67), and interacted with treatment to increase probability of pregnancy at 90 DIM (OR 2.39) relative to control counterparts. It is suggested that when administered with efficient cooling, combined hormonal treatment in specific subgroups of cows, that is, those previously diagnosed with postpartum uterine disease or those with low body condition score or low milk yield might improve fertility during the summer and autumn. Integration of such an approach into reproductive management during the hot seasons might improve treatment efficiency and reduce expenses. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Application of normal fluorescence and stability-indicating derivative synchronous fluorescence spectroscopy for the determination of gliquidone in presence of its fluorescent alkaline degradation product

NASA Astrophysics Data System (ADS)

El-ghobashy, Mohamed R.; Yehia, Ali M.; Helmy, Aya H.; Youssef, Nadia F.

2018-01-01

Simple, smart and sensitive normal fluorescence and stability-indicating derivative synchronous spectrofluorimetric methods have been developed and validated for the determination of gliquidone in the drug substance and drug product. Normal spectrofluorimetric method of gliquidone was established in methanol at λ excitation 225 nm and λ emission 400 nm in concentration range 0.2-3 μg/ml with LOD equal 0.028. The fluorescence quantum yield of gliquidone was calculated using quinine sulfate as a reference and found to be 0.542. Stability-indicating first and third derivative synchronous fluorescence spectroscopy were successfully utilized to overcome the overlapped spectra in normal fluorescence of gliquidone and its alkaline degradation product. Derivative synchronous methods are based on using the synchronous fluorescence of gliquidone and its degradation product in methanol at Δ λ50 nm. Peak amplitude in the first derivative of synchronous fluorescence spectra was measured at 309 nm where degradation product showed zero-crossing without interference. The peak amplitudes in the third derivative of synchronous fluorescence spectra, peak to trough were measured at 316,329 nm where degradation product showed zero-crossing. The different experimental parameters affecting the normal and synchronous fluorescence intensity of gliquidone were studied and optimized. Moreover, the cited methods have been validated as per ICH guidelines. The peak amplitude-concentration plots of the derivative synchronous fluorescence were linear over the concentration range 0.05-2 μg/ml for gliquidone. Limits of detection were 0.020 and 0.022 in first and third derivative synchronous spectra, respectively. The adopted methods were successfully applied to commercial tablets and the results demonstrated that the derivative synchronous fluorescence spectroscopy is a powerful stability-indicating method, suitable for routine use with a short analysis time. Statistical comparison between the results obtained by normal fluorescence and derivative synchronous methods and the official one using student's t-test and F-ratio showed no significant difference regarding accuracy and precision.

Overview of Cell Synchronization.

PubMed

Banfalvi, Gaspar

2017-01-01

The widespread interest in cell synchronization is maintained by the studies of control mechanism involved in cell cycle regulation. During the synchronization distinct subpopulations of cells are obtained representing different stages of the cell cycle. These subpopulations are then used to study regulatory mechanisms of the cycle at the level of macromolecular biosynthesis (DNA synthesis, gene expression, protein synthesis), protein phosphorylation, development of new drugs, etc. Although several synchronization methods have been described, it is of general interest that scientists get a compilation and an updated view of these synchronization techniques. This introductory chapter summarizes: (1) the basic concepts and principal criteria of cell cycle synchronizations, (2) the most frequently used synchronization methods, such as physical fractionation (flow cytometry, dielectrophoresis, cytofluorometric purification), chemical blockade, (3) synchronization of embryonic cells, (4) synchronization at low temperature, (5) comparison of cell synchrony techniques, (6) synchronization of unicellular organisms, and (7) the effect of synchronization on transfection.

Effect of follicle age on conception rate in beef heifers.

PubMed

Abreu, F M; Cruppe, L H; Maquivar, M; Utt, M D; Madsen, C A; Vasconcelos, J L M; Mussard, M L; Day, M L; Geary, T W

2014-03-01

The objective of this study was to determine the effect of age of the ovulatory follicle on fertility in beef heifers. Ovulation was synchronized with the 5 d CO-Synch + controlled intravaginal drug release (CIDR) program in heifers in Montana (MT; n = 162, Hereford and Angus Crossbred) and Ohio (OH; n = 170, Angus Crossbred). All heifers received estradiol benzoate (EB; 1 mg/500 kg BW, [i.m.]) 6 d after the final GnRH of the synchronization program to induce follicular atresia and emergence of a new follicular wave (NFW) followed by prostaglandin F2α (PGF(2α); 25 mg, i.m.) administration either 5 d ("young" follicle [YF]; n = 158) or 9 d ("mature" follicle [MF]; n = 174) after EB. Estrous detection was performed for 5 d after PGF(2α) with AI approximately 12 h after onset of estrus. Ovarian ultrasonography (MT location only) was performed in YF and MF at EB, 5 d after EB, PGF(2α), and AI. Heifers in MT (n = 20) and OH (n = 18) that were not presynchronized or did not initiate a NFW were excluded from further analyses, resulting in 142 and 152 heifers in MT and OH, respectively. Heifers from the MF treatment in MT that initiated a second NFW after EB but before PGF(2α) (MF2; n = 14) were excluded from the primary analysis. In the secondary analysis, the MF2 group was compared to MF and YF treatments in MT. Estrous response was similar (90%; 252/280) between treatments and locations. Proestrus interval (from PGF(2α) to estrus) and age of the ovulatory follicle at AI were similar for MF heifers between locations (54.6 ± 1.7 h and 8.3 ± 0.07 h) but were greater (P < 0.01) for YF heifers in OH (78.5 ± 1.4 h and 5.3 ± 0.06 h) than MT (67.4 ± 1.6 h and 4.8 ± 0.06 h; treatment × location, P < 0.01). However, conception rate did not differ for MF (63.8%; 74/116) and YF (67.0%; 91/136) treatments. In the MT heifers, follicle size and follicle age at AI in the YF treatment (10.4 ± 0.15 mm and 4.8 ± 0.06 d, respectively) was less (P < 0.01) than in the MF treatment (11.0 ± 0.18 mm and 8.3 ± 0.11 d, respectively), but conception rate to AI did not differ between treatments in MT. In the MF2 group proestrus interval was greater (P < 0.01); hence, diameter of the ovulatory follicle and age were similar to that for the YF treatment. Conception rate to AI did not differ between MF2, MF, and YF (61.5, 63.3, and 64.7%, respectively) in MT. In conclusion, manipulation of age of the nonpersistent ovulatory follicle at spontaneous ovulation did not influence conception rate.

Statistically rigorous calculations do not support common input and long-term synchronization of motor-unit firings.

PubMed

De Luca, Carlo J; Kline, Joshua C

2014-12-01

Over the past four decades, various methods have been implemented to measure synchronization of motor-unit firings. In this work, we provide evidence that prior reports of the existence of universal common inputs to all motoneurons and the presence of long-term synchronization are misleading, because they did not use sufficiently rigorous statistical tests to detect synchronization. We developed a statistically based method (SigMax) for computing synchronization and tested it with data from 17,736 motor-unit pairs containing 1,035,225 firing instances from the first dorsal interosseous and vastus lateralis muscles--a data set one order of magnitude greater than that reported in previous studies. Only firing data, obtained from surface electromyographic signal decomposition with >95% accuracy, were used in the study. The data were not subjectively selected in any manner. Because of the size of our data set and the statistical rigor inherent to SigMax, we have confidence that the synchronization values that we calculated provide an improved estimate of physiologically driven synchronization. Compared with three other commonly used techniques, ours revealed three types of discrepancies that result from failing to use sufficient statistical tests necessary to detect synchronization. 1) On average, the z-score method falsely detected synchronization at 16 separate latencies in each motor-unit pair. 2) The cumulative sum method missed one out of every four synchronization identifications found by SigMax. 3) The common input assumption method identified synchronization from 100% of motor-unit pairs studied. SigMax revealed that only 50% of motor-unit pairs actually manifested synchronization. Copyright © 2014 the American Physiological Society.

Hybrid Chaos Synchronization of Four-Scroll Systems via Active Control

NASA Astrophysics Data System (ADS)

Karthikeyan, Rajagopal; Sundarapandian, Vaidyanathan

2014-03-01

This paper investigates the hybrid chaos synchronization of identical Wang four-scroll systems (Wang, 2009), identical Liu-Chen four-scroll systems (Liu and Chen, 2004) and non-identical Wang and Liu-Chen four-scroll systems. Active control method is the method adopted to achieve the hybrid chaos synchronization of the four-scroll chaotic systems addressed in this paper and our synchronization results are established using Lyapunov stability theory. Since the Lyapunov exponents are not required for these calculations, the active control method is effective and convenient to hybrid synchronize identical and different Wang and Liu-Chen four-scroll chaotic systems. Numerical simulations are also shown to illustrate and validate the hybrid synchronization results derived in this paper.

A comparison of frame synchronization methods. [Deep Space Network

NASA Technical Reports Server (NTRS)

Swanson, L.

1982-01-01

Different methods are considered for frame synchronization of a concatenated block code/Viterbi link. Synchronization after Viterbi decoding, synchronization before Viterbi decoding based on hard-quantized channel symbols are all compared. For each scheme, the probability under certain conditions of true detection of sync within four 10,000 bit frames is tabulated.

Compared to dinoprost tromethamine, cloprostenol sodium increased rates of estrus detection, conception and pregnancy in lactating dairy cows on a large commercial dairy.

PubMed

Pursley, J R; Martins, J P N; Wright, C; Stewart, N D

2012-09-01

Using two PGF(2α) treatments 14 days apart as a way to enhance estrus detection rate following the 2nd treatment is a reproductive management tool that continues to be used on large dairy farms. In one study, in cows with a functional CL and a dominant follicle, treatment with cloprostenol vs. dinoprost resulted in greater peripheral estradiol concentrations. The objective of the present study was to determine if cloprostenol could enhance pregnancy rates of cows in a large dairy herd using a PGF(2α) program for 1st artificial insemination (AI). Lactating dairy cows (n = 4549) were randomly assigned to receive two treatments of either 500 μg cloprostenol or 25 mg dinoprost 14 days apart, with the 2nd treatment on the 1st day of the voluntary waiting period (57 DIM). Cows detected in estrus within 5 days after the 2nd treatment were inseminated. There was no effect of treatment on day of estrus detection, with 78% of cows inseminated on Days 3 or 4 following treatment. Cloprostenol increased (P < 0.01) estrus detection rates in 1st parity cows compared to dinoprost, 42.4 vs. 34.0%. In cows inseminated on Days 3 or 4 after treatment, cloprostenol increased (P = 0.05) conception rates compared to dinoprost, 38.3 vs. 34.4%. When treatments and parities were combined, conception rates increased (P < 0.02) with interval after treatment (27.0, 36.4, and 44.5% for Days 1 or 2, Days 3 or 4, and Day 5, respectively). Cloprostenol increased (P = 0.02) overall pregnancy rate compared to dinoprost, 14.4 vs. 12.2%. In summary, cloprostenol increased fertility in 1st parity cows inseminated on Days 3 or 4 following treatment and subsequently enhanced pregnancy rates of 1st parity lactating dairy cows compared to dinoprost. Fertility appeared greater in cows expected to have had a young antral ovarian follicle at treatment. Copyright © 2012 Elsevier Inc. All rights reserved.

Subcutaneous body lipids affect cyclicity and estrus behavior in primiparous Charolais cows.

PubMed

Recoules, E; De La Torre, A; Agabriel, J; Egal, D; Blanc, F

2013-08-01

Conception rate and the calving interval of beef cows are known to be influenced by body reserves at calving and subsequent postpartum changes. However, few studies have focused on the effect of body reserve dynamics on both postpartum cyclicity and estrus expression. Two successive similar experiments (Year 1: n=14; Year 2: n=16) were carried out on primiparous Charolais cows reared indoors during winter to quantify the effects of adipose cell diameter at calving (ACDca) and their postpartum changes (ACDch) on cyclicity and estrus behavior. Cows were managed to calve with a body condition score (BCS, scale 0-5) of 2.5 (Year 1) and 1.5 (Year 2). After calving cows were assigned to a Low vs. a High energy level diet until turn out to pasture in May. Within years ACDca was similar between Low and High groups whereas calving to turnout changes of body weight (BW), BCS and adipose cell diameter differed (P<0.0001). The interval between calving and resumption of luteal activity was negatively correlated with ACDca (P=0.001). Estrus duration (interval between first and last standing to be mounted (STBM)) was longer in Low than in High groups (P=0.02). Number of STMB was higher in Low than in High cows. Adipose cell diameter at calving and postpartum changes had distinct effects on the components of reproductive performance; emphasizing the need to consider both amounts and changes of body lipids to predict relationships between nutrition and reproduction in cows. Copyright © 2013 Elsevier B.V. All rights reserved.

Nonpuberal estrus and mature cow influences on growth and puberty in heifers.

PubMed

Nelsen, T C; Short, R E; Phelps, D A; Staigmiller, R B

1985-08-01

This experiment had two objectives. The first was to test a hypothesis that the presence of mature cows can influence the growth rate and physiological maturation rate of growing heifers. The second objective was to define a phenomenon termed nonpuberal estrus (NPE). Nonpuberal estrus in a prepuberal heifer is a behavioral estrus that is not followed by ovulation and formation of a corpus luteum. Two years of data were collected. All heifers were crossbred and were sired by Hereford, Charolais and Tarentaise bulls in yr 1 (n = 153) and by the same three breeds plus Jersey, Shorthorn, Brahman and Longhorn in yr 2 (n = 207). All heifers were born in the spring and weaned in October when approximately 180 d old. After weaning, heifers were assigned at random (within breed of sire) to control or mature cow (MC) treatment pens. Control pens contained 25 or 26 heifers and a sterile marker bull, while MC pens contained 25 or 26 heifers and a sterile marker bull plus four nonpregnant, mature cows. The presence of the mature cows did not (P greater than .10) affect rate of gain or yearling weight. Sire breed did (P less than .01) influence weight on test and average daily gain during the test in both years and affected (P less than .01) yearling weight during yr 2 but not (P greater than .10) during yr 1. A sire breed X treatment interaction effect on puberal traits was significant (P less than .01) in yr 1 but not in yr 2.(ABSTRACT TRUNCATED AT 250 WORDS)

Mathematical foundations of hybrid data assimilation from a synchronization perspective

NASA Astrophysics Data System (ADS)

Penny, Stephen G.

2017-12-01

The state-of-the-art data assimilation methods used today in operational weather prediction centers around the world can be classified as generalized one-way coupled impulsive synchronization. This classification permits the investigation of hybrid data assimilation methods, which combine dynamic error estimates of the system state with long time-averaged (climatological) error estimates, from a synchronization perspective. Illustrative results show how dynamically informed formulations of the coupling matrix (via an Ensemble Kalman Filter, EnKF) can lead to synchronization when observing networks are sparse and how hybrid methods can lead to synchronization when those dynamic formulations are inadequate (due to small ensemble sizes). A large-scale application with a global ocean general circulation model is also presented. Results indicate that the hybrid methods also have useful applications in generalized synchronization, in particular, for correcting systematic model errors.

Mathematical foundations of hybrid data assimilation from a synchronization perspective.

PubMed

Penny, Stephen G

2017-12-01

The state-of-the-art data assimilation methods used today in operational weather prediction centers around the world can be classified as generalized one-way coupled impulsive synchronization. This classification permits the investigation of hybrid data assimilation methods, which combine dynamic error estimates of the system state with long time-averaged (climatological) error estimates, from a synchronization perspective. Illustrative results show how dynamically informed formulations of the coupling matrix (via an Ensemble Kalman Filter, EnKF) can lead to synchronization when observing networks are sparse and how hybrid methods can lead to synchronization when those dynamic formulations are inadequate (due to small ensemble sizes). A large-scale application with a global ocean general circulation model is also presented. Results indicate that the hybrid methods also have useful applications in generalized synchronization, in particular, for correcting systematic model errors.

Abortion and subsequent excretion of chlamydiae from the reproductive tract of sheep during estrus.

PubMed Central

Papp, J R; Shewen, P E; Gartley, C J

1994-01-01

Chlamydia psittaci serovar 1 infection in pregnant sheep typically causes abortion or the birth of weak lambs. Eight sheep that experienced chlamydia-induced abortion during their first pregnancy were successfully rebred yearly for the past 2 years. Chlamydia-specific lipopolysaccharide was detectable for approximately 3 weeks in vaginal swabs taken from the experimentally infected sheep following abortion. There was no evidence of chlamydiae in vaginal, placental, or neonatal samples obtained immediately after each subsequent successful pregnancy. Sera collected from the experimentally infected sheep had persistent, high antibody levels to C. psittaci, suggesting continued exposure of the immune system to the organism. Examination of vaginal specimens obtained during various stages of the estrus cycle revealed detectable levels of chlamydiae only when the animal was near ovulation. Chlamydiae were not detected in swabs from sheep that did not experience abortion. Enhanced chlamydial excretion during the periovulation period of sheep may provide sufficient stimulation of the immune system to account for the persistent antibody response. Furthermore, the association between estrus and chlamydial shedding has important implications for transmission of infection to other ewes during breeding. PMID:8063395

On Synchronization Primitive Systems.

DTIC Science & Technology

The report studies the question: what synchronization primitive should be used to handle inter-process communication. A formal model is presented...between these synchronization primitives. Although only four synchronization primitives are compared, the general methods can be used to compare other... synchronization primitives. Moreover, in the definitions of these synchronization primitives, conditional branches are explicitly allowed. In addition

Monitoring of embryonic and fetal losses in different breeds of goats using real-time B-mode ultrasonography.

PubMed

Samir, Haney; Karen, Aly; Ashmawy, Tarek; Abo-Ahmed, Mostafa; El-Sayed, Mohamed; Watanabe, Gen

2016-01-15

Compared to cattle and sheep, few studies had been undertaken to evaluate the incidence of embryonic and fetal losses (EFL) in goats. The objectives of the present study were to characterize the timing of EFL and to identify the factors that are associated with EFL in goats such as breed, age, parity, method of estrous synchronization, and breeding. Moreover, this study aimed to ensure whether a relationship existed between serum progesterone (P4) and EFL. Goats (n = 151) of different breeds (70 Zaraiebi, 42 Damascus, and 39 Cross goats [Baladi × Damascus]) were evaluated by ultrasonography to monitor EFL during different stages of gestation (D20-23, D26-29, D33-36, D40-45, and D47-54 after breeding). Blood samples were collected at D7, D20, and at each ultrasonographic scanning to clarify changes of serum P4 levels concurrently with EFL. Results revealed that 45 of 109 goats (41.28%) were exposed to EFL. A higher EFL % was observed between D20 to 23 and D47 to 54 (19.61%) compared with D47 to 54 to birth (11.76%). Moreover, a higher EFL % was observed in Zaraiebi goats compared with others. Age and goat parity had no significant effect on the EFL % in all goats. A high EFL % were observed in goats synchronized by P4 sponge, as well as artificially inseminated goats compared with goats with spontaneous estrus, and bred by natural mating, respectively. Serum P4 at D7 or D20 after breeding showed nonsignificant difference between normal pregnant goats and goats that experienced EFL. Unlike goats that experienced partial EFL, goats that experienced total EFL between D20 to 23 and D26 to 29 showed an abrupt P4 reduction (85.06%; P < 0.01) suggesting the probability of endocrine disruption of the CL. However, goats that were exposed to total EFL between D26 and 29 to D33 to 36 showed a low P4 reduction (24.90%; P < 0.05), which might be considered as an effect rather than a cause of EFL. In conclusion, different factors such as breed, estrous synchronization, breeding, and stage of pregnancy may be involved in EFL in goats. Therefore, improvement of the goat management in the early stage of pregnancy is important to decrease EFL % in goats. Although the P4 did not show any significant difference between normal pregnancy goats and goats that experienced EFL, CL disruption should be taken into the consideration, at least, in goats exposed to total embryonic losses. Copyright © 2016 Elsevier Inc. All rights reserved.

Body condition loss and increased serum levels of nonesterified fatty acids enhance progesterone levels at estrus and reduce estrous activity and insemination rates in postpartum dairy cows.

PubMed

Lüttgenau, J; Purschke, S; Tsousis, G; Bruckmaier, R M; Bollwein, H

2016-03-01

Data from 96 Holstein Friesian cows on a commercial dairy farm were used to investigate whether body condition and serum levels of nonesterified fatty acids (NEFAs) postpartum (pp) affect progesterone (P4) levels, estrous activity, and fertility in dairy cows. The examination period started 14 days before the expected calving date and ended either when a cow was inseminated or at a maximum of 90 days pp. Body condition score (BCS; 1-5 scale) and backfat thickness (BFT) were determined every 2 weeks. Blood for analysis of NEFA and P4 concentrations was sampled weekly during the first 35 days pp and then every 48 hours until an ovulation was observed. Transrectal ultrasonography of the ovaries started at 21 days pp and was performed after blood sampling. If cows were not inseminated because of silent ovulation, sampling and ultrasonography continued on Days 7, 14, and 18 after ovulation and again every 48 hours until the next ovulation. Estrous activity was continuously measured with the Heatime estrus detection system. Pregnancy controls were performed ultrasonographically 28 and 42 days after AI. Cows with increased NEFA levels at 28 days pp had an increased risk of maintaining minimum P4 levels above 0.4 ng/mL at first recognized estrus (P = 0.03). Higher NEFA levels at Day 7 were associated with lower probability for a cow to have elevated P4 levels (≥2 ng/mL) by Day 35 pp, indicating delayed commencement of luteal activity (C-LA). Estrous activity was not influenced (P > 0.10) by minimum P4 concentrations at estrus, but more animals with C-LA until Day 35 pp showed estrous activity compared to cows without C-LA throughout this period (P = 0.006). Estrous activity was lower in cows with a low BCS 14 days pp (P = 0.02) and with a low BFT 42 days pp (P = 0.03). Moreover, the probability to exhibit estrus was reduced with higher NEFA levels at 21 days pp (P = 0.01). Eighty-five cows were inseminated and 37 (44%) got pregnant after insemination. Higher NEFA levels, especially 14, 28, and 42 days pp, were associated with lower probability to inseminate a cow. Regarding the cows that were inseminated, no influence of BCS, BFT, or NEFA levels on pregnancy per artificial insemination was found. In conclusion, cows with higher loss of body condition and elevated NEFA concentrations had higher P4 concentrations during estrus, a reduced estrous activity and insemination rate, but no depression in pregnancy per artificial insemination. Copyright © 2016 Elsevier Inc. All rights reserved.

The influence of azaperone treatment at weaning on reproductive performance of sows: altering effects of season and parity.

PubMed

Schwarz, T; Nowicki, J; Tuz, R; Bartlewski, P M

2018-02-01

Azaperone treatment can control aggression and decrease stress due to weaning, re-grouping and hierarchical fighting of gilts and sows. However, the effects of this butyrophenone neuroleptic and sedative administered at weaning on pig reproductive function are poorly characterized. In this year-long study, a total of 619 cross-bred sows (Polish Large White×Polish Landrace) kept on a commercial farm received an i.m. injection of azaperone (Stresnil®; 2 mg/kg BW) just before weaning and were artificially inseminated during the ensuing estrus with 3×109 spermatozoa per dose of an inseminate; 1180 sows served as untreated controls. Immediately after weaning, the sows were moved to four pens of seven to nine animals each. A teaser boar was used twice daily to check for estrus and sows were bred at heat detection. Subsequently, all sows stayed in individual stalls until pregnancy testing on day 30 post-artificial insemination and were then re-grouped until farrowing. The proportion of pigs that were in estrus within 6 days post-weaning was significantly lower in azaperone-treated groups of animals than in controls (71.4% v. 84.2%). Overall, the azaperone-treated sows had a significantly longer weaning-to-estrus interval (WEI; 8.7±10.1 v. 6.3±8.1 days; mean±SD) and a significantly larger litter size (LS: 11.8±3.0 v.11.3±3.2; azaperone-treated v. control sows). Treatment of the winter-farrowing sows was associated with increased LS (12.8±2.6 and 11.3±3.1 piglets/sow, respectively; P<0.05) and longer (P<0.05) weaning-to-effective-service intervals (11.7±19.3 and 8.4±12.3 days, respectively) as well as farrowing intervals (155.7±19.7 and 152.2±16.1 days, respectively) compared with untreated controls. In the summer months, significantly longer WEIs (12.1±21.0 v. 8.4±16.9 days) were accompanied by a significant decline in LS only in azaperone-treated sows that were inseminated within 6 days post-weaning (10.8±2.9 v. 11.5±3.3 piglets/sow; azaperone-treated v. controls). Azaperone-treated second parity sows had greater LS (P<0.001) along with prolonged WEIs (P<0.05) in comparison to their respective controls, regardless of the timing of estrus. An application of azaperone at weaning increased the annual piglet productivity of winter-farrowing animals and of second parity sows but depressed it significantly in summer. The extra cost and labor due to delayed onset of estrus may cancel out any reproductive benefits of azaperone treatment.

Damping torque analysis of VSC-based system utilizing power synchronization control

NASA Astrophysics Data System (ADS)

Fu, Q.; Du, W. J.; Zheng, K. Y.; Wang, H. F.

2017-05-01

Power synchronization control is a new control strategy of VSC-HVDC for connecting a weak power system. Different from the vector control method, this control method utilizes the internal synchronization mechanism in ac systems, in principle, similar to the operation of a synchronous machine. So that the parameters of controllers in power synchronization control will change the electromechanical oscillation modes and make an impact on the transient stability of power system. This paper present a mathematical model for small-signal stability analysis of VSC station used power synchronization control and analyse the impact of the dynamic interactions by calculating the contribution of the damping torque from the power synchronization control, besides, the parameters of controllers which correspond to damping torque and synchronous torque in the power synchronization control is defined respectively. At the end of the paper, an example power system is presented to demonstrate and validate the theoretical analysis and associated conclusions are made.

Induction of mammary tumors in rat by intraperitoneal injection of NMU: histopathology and estral cycle influence.

PubMed

Rivera, E S; Andrade, N; Martin, G; Melito, G; Cricco, G; Mohamad, N; Davio, C; Caro, R; Bergoc, R M

1994-11-11

In order to obtain an experimental model we induced mammary tumors in female Sprague-Dawley rats. The carcinogen N-nitroso-N-methylurea (NMU) was injected intraperitoneally (i.p.) at doses of 50 mg/kg body weight when animals were 50, 80 and 110 days old. Tumor sizes were measured with a caliper and their growth parameters and histopathological properties were tested. For 100 rats, 88.4% of developed lesions were ductal carcinomas, histologically classified as 52.8% cribiform variety, 30.6% solid carcinoma. Metastases in liver, spleen and lung were present. Other primary tumors were detected with low incidence. The influence of the rat estrous cycle during the first exposure to intraperitoneal NMU injection was studied. The latency period in estrus, proestrus and diestrus was 82 +/- 15, 77 +/- 18 and 79 +/- 18 days, respectively. Tumor incidence was significantly higher in estrus (95.2%) than proestrus (71.4%) or diestrus (77.4), (P < 0.01). Mean number or tumors per animal was similar among the three groups (4.4 +/- 3.2, 3.8 +/- 3.6, 3.2 +/- 1.8). The procedure described appears to be the simplest method for inducing experimental mammary tumors in rats.

A Three-day PGF2α Plus eCG-based Fixed-time AI Protocol Improves Fertility Compared with Spontaneous Estrus in Dairy Cows with Silent Ovulation

PubMed Central

GARCIA-ISPIERTO, Irina; LÓPEZ-GATIUS, Fernando

2013-01-01

Abstract This study was designed to test the treatment with prostaglandin F2α (PGF2α) plus equine chorionic gonadotrophin (eCG) and GnRH 48 h later (PEG protocol) followed by fixed-time AI (FTAI) in dairy cows with silent ovulation (cows with a mature corpus luteum and no signs of estrus detected in the preceding 21 days). In Experiment I, ovulation following the PEG protocol monitored in 24 cows with silent ovulation was recorded in 83% of the cows 36 h after GnRH treatment. In Experiment II, control cows were artificially inseminated during spontaneous estrus (4615 AI), while cows in the PEG group (1266 AI) were subjected to FTAI 24 h after GnRH treatment. Binary logistic regression revealed a significant effect of the interactions of treatment by season, by parity or by repeat breeding syndrome (>3 AI) on the conception rate. The conception rate was negatively affected by the warm season and age in controls but not in treated cows, whereas repeat breeder cows in the control and PEG groups were less (by a factor of 0.7) or more (by a factor of 1.5) likely to become pregnant, respectively, than the remaining animals. Moreover, the likelihood of twin pregnancy was lower in multiparous PEG (by a factor of 0.4) cows than in the remaining cows. This protocol, besides overcoming the negative effects of heat stress and age on the conception rate, increased fertility in repeat breeder cows compared with spontaneous estrus. Moreover, this treatment regimen reduced the twin pregnancy rate in multiparous cows. PMID:23698789

Effects of breed, age, season, and multiple ovulations on cyclic, PGF2α-induced, and postpartum estrus characteristics in Spanish jennies.

PubMed

Perez-Marin, C C; Galisteo, I; Perez-Rico, A; Galisteo, J

2016-04-01

This retrospective, population-based, cross-sectional study analyzed data for a total of 104 jennies reared in southern Spain over the period 1995 to 2014. Intervals to ovulation and incidence of multiple ovulation and pregnancy were charted for spontaneous, PGF2α-induced, and postpartum estrous cycles. In spontaneous estrous cycles, the interovulatory interval varied as a function of breed (P < 0.03) and month of ovulation (P < 0.01), and duration of estrus signs was longer in older jennies (0.04). Spontaneous cycles were also associated with higher ovulation rates from September to January (P < 0.006). When PGF2α was used to induce the estrus, not only did estrus signs last longer in old (P < 0.004) and in polyovular (0.02) jennies but old jennies also displayed significantly higher ovulation rates (P < 0.03). In postpartum jennies, no variations were observed as a function of any of the independent variables analyzed. Comparison of ovulation rates between different types of cycle revealed that postpartum jennies exhibited significantly lower ovulation rates (1.32 ± 0.07) and a lower incidence of multiple ovulation (30.4%) than spontaneous (1.62 ± 0.04, 55.0%) and PGF2α-induced (1.74 ± 0.08, 65.5%) groups. No differences were observed in the incidence of ovulation or pregnancy depending on the location of ovulation in polyovular cycles, and ovulation occurred at similar rates in the right and left ovaries. These findings shed further light on reproductive physiology in jennies and may be of value in improving animal management. Copyright © 2016 Elsevier Inc. All rights reserved.

The number of service per conception of Indonesian Friesian Holstein with artificial insemination in Selo, Boyolali, Central Java, Indonesia

NASA Astrophysics Data System (ADS)

Wicaksono, A. M.; Pramono, A.; Susilowati, A.; Sutarno; Widyas, N.; Prastowo, S.

2018-03-01

Boyolali is an area in Central Java Indonesia, it has large number of Indonesian Friesian Holstein (IFH; dairy cattle). To improve its population as well as genetic quality of milk production, artificial insemination (AI) is widely applied as mating program. The success of AI can be evaluated from the number of service per conception (S/C), represent a number of service using AI to achieve one pregnancy. Its mirroring mating management and reproductive efficiency in dairy cattle, estimated in herd during specific time and location. For that, this study aims to estimate S/C in Selo, Boyolali during October 2016 to January 2017. Data were gathered with 95% confidence level. Sample size were 367 IFH, visited and selected purposively based on criteria one-time partus, 3 y.o and have complete AI record. Animal data were collected in reproduction and mating management. In addition, 124 dairy farmer who have minimum 5 years experiences in rearing IFH cow were interviewed as respondent in estrus detection, followed with 2 skilled inseminators for AI performing time data. Result shows that S/C is 1.71, this mean one pregnancy need 1.71 times AI services. In the estrus detection, most of dairy farmers were able to observe estrus sign in vulva color, size and the present of mucus by visual. Moreover, AI was performed in 9 to 12 hours after the sign of estrus observed. It is concluded that AI of IFH in Selo, Boyolali has been successfully applied, however there are still rooms to improve the reproduction efficiency through mating management in regard to lower S/C.

Synchronization Design and Error Analysis of Near-Infrared Cameras in Surgical Navigation.

PubMed

Cai, Ken; Yang, Rongqian; Chen, Huazhou; Huang, Yizhou; Wen, Xiaoyan; Huang, Wenhua; Ou, Shanxing

2016-01-01

The accuracy of optical tracking systems is important to scientists. With the improvements reported in this regard, such systems have been applied to an increasing number of operations. To enhance the accuracy of these systems further and to reduce the effect of synchronization and visual field errors, this study introduces a field-programmable gate array (FPGA)-based synchronization control method, a method for measuring synchronous errors, and an error distribution map in field of view. Synchronization control maximizes the parallel processing capability of FPGA, and synchronous error measurement can effectively detect the errors caused by synchronization in an optical tracking system. The distribution of positioning errors can be detected in field of view through the aforementioned error distribution map. Therefore, doctors can perform surgeries in areas with few positioning errors, and the accuracy of optical tracking systems is considerably improved. The system is analyzed and validated in this study through experiments that involve the proposed methods, which can eliminate positioning errors attributed to asynchronous cameras and different fields of view.

Frequency-varying synchronous micro-vibration suppression for a MSFW with application of small-gain theorem

NASA Astrophysics Data System (ADS)

Peng, Cong; Fan, Yahong; Huang, Ziyuan; Han, Bangcheng; Fang, Jiancheng

2017-01-01

This paper presents a novel synchronous micro-vibration suppression method on the basis of the small gain theorem to reduce the frequency-varying synchronous micro-vibration forces for a magnetically suspended flywheel (MSFW). The proposed synchronous micro-vibration suppression method not only eliminates the synchronous current fluctuations to force the rotor spinning around the inertia axis, but also considers the compensation caused by the displacement stiffness in the permanent-magnet (PM)-biased magnetic bearings. Moreover, the stability of the proposed control system is exactly analyzed by using small gain theorem. The effectiveness of the proposed micro-vibration suppression method is demonstrated via the direct measurement of the disturbance forces for a MSFW. The main merit of the proposed method is that it provides a simple and practical method in suppressing the frequency varying micro-vibration forces and preserving the nominal performance of the baseline control system.

A dynamical systems approach for estimating phase interactions between rhythms of different frequencies from experimental data.

PubMed

Onojima, Takayuki; Goto, Takahiro; Mizuhara, Hiroaki; Aoyagi, Toshio

2018-01-01

Synchronization of neural oscillations as a mechanism of brain function is attracting increasing attention. Neural oscillation is a rhythmic neural activity that can be easily observed by noninvasive electroencephalography (EEG). Neural oscillations show the same frequency and cross-frequency synchronization for various cognitive and perceptual functions. However, it is unclear how this neural synchronization is achieved by a dynamical system. If neural oscillations are weakly coupled oscillators, the dynamics of neural synchronization can be described theoretically using a phase oscillator model. We propose an estimation method to identify the phase oscillator model from real data of cross-frequency synchronized activities. The proposed method can estimate the coupling function governing the properties of synchronization. Furthermore, we examine the reliability of the proposed method using time-series data obtained from numerical simulation and an electronic circuit experiment, and show that our method can estimate the coupling function correctly. Finally, we estimate the coupling function between EEG oscillation and the speech sound envelope, and discuss the validity of these results.

Low-cost synchronization of high-speed audio and video recordings in bio-acoustic experiments.

PubMed

Laurijssen, Dennis; Verreycken, Erik; Geipel, Inga; Daems, Walter; Peremans, Herbert; Steckel, Jan

2018-02-27

In this paper, we present a method for synchronizing high-speed audio and video recordings of bio-acoustic experiments. By embedding a random signal into the recorded video and audio data, robust synchronization of a diverse set of sensor streams can be performed without the need to keep detailed records. The synchronization can be performed using recording devices without dedicated synchronization inputs. We demonstrate the efficacy of the approach in two sets of experiments: behavioral experiments on different species of echolocating bats and the recordings of field crickets. We present the general operating principle of the synchronization method, discuss its synchronization strength and provide insights into how to construct such a device using off-the-shelf components. © 2018. Published by The Company of Biologists Ltd.

Content-based intermedia synchronization

NASA Astrophysics Data System (ADS)

Oh, Dong-Young; Sampath-Kumar, Srihari; Rangan, P. Venkat

1995-03-01

Inter-media synchronization methods developed until now have been based on syntactic timestamping of video frames and audio samples. These methods are not fully appropriate for the synchronization of multimedia objects which may have to be accessed individually by their contents, e.g. content-base data retrieval. We propose a content-based multimedia synchronization scheme in which a media stream is viewed as hierarchial composition of smaller objects which are logically structured based on the contents, and the synchronization is achieved by deriving temporal relations among logical units of media object. content-based synchronization offers several advantages such as, elimination of the need for time stamping, freedom from limitations of jitter, synchronization of independently captured media objects in video editing, and compensation for inherent asynchronies in capture times of video and audio.

[The effect of synchronization on estrus and pregnancy in sheep and on levels of thyroxine, triiodothyronine, 17 beta-estradiol, progesterone and cholesterol].

PubMed

Bekeová, E; Krajnicáková, M; Hendrichovský, V; Maracek, I

1991-07-01

Knowledge of pathogenesis of sexual dysfunctions at altered thyroid activity is limited by the knowledge of multiple and ubiquitous action of its hormones throughout the organism. One of the possibilities of modulatory influence of thyroid hormones on sexual functions can be realized through the participation of thyroxine and triiodothyronine in the synthesis and metabolism of primary substrate of steroid synthesis--cholesterol. The presented work is aimed at the study of simultaneous dynamic changes of concentrations of thyroxine (T4), triiodothyronine (T3), 17 beta-estradiol (E2), progesterone (P4) and cholesterol (Chol) during synchronization of the rutting period and gravidity at parallel correlative evaluation of mutual relations of the followed parameters in ten Merino sheep in the seasonal period. Synchronization was achieved by chlorsuperlutin (Agelin--vaginal swabs, Spofa; 20 mg of chlorsuperlutin/swab) and PMSG (500 I. U./animal). Blood was sampled by means of a jugular vein puncture at the time of swab insertion (-13th day) and after three (-10th day) and seven (-7th day) following days, at the removal of swabs and application of PMSG (-3rd day), on the day of insemination (zero day), on the 7th, 14th and 17th day and in the middle of the 2nd, 3rd, 4th and 5th month of gravidity. In the phase of oestrus synchronization a significant increase of E2 concentrations on days -7 and -3 of the experiment (0.47 +/- 0.079 and 0.542 +/- 0.177 nmol.l-1 of serum, P less than 0.001; P less than 0.001) was observed compared to the E2 values on day -13 (0.084 +/- 0.036 nmol.l-1 of serum). Parallel to these observations, marked intermittent changes of T4 (Tab. I, Graph 1) were recorded with the lowest values of this parameter observed on days -10 (41.75 +/- 20.23, P less than 0.05) and -3 (50.22 +/- 18.77, P less than 0.05) and the highest on day -7 (96.77 +/- 17.51 nmol.l-1, P less than 0.01) and day zero (85.40 +/- 19.59 nmol.l-1 of serum, P less than 0.05) in comparison with the -13th day (67.22 +/- 18.29 nmol.l-1 of serum). Concentrations of P4 (Tab. I, Graph 4) declined to the lowest values on day zero observation (0.09 +/- 0.08 nmol.l-1 of serum, P less than 0.05 vs 3.40 +/- 3.61 nmol.l-1 on day -13). No significant changes of concentrations of T3 (Tab. I, Graph 2) and Chol (Tab. I, Graph 5) were observed during oestrus synchronization. During gravidity, concentrations of E2 (Tab. I Graph 3) showed an increasing trend compared to the -13th day.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of resynchronization with GnRH or progesterone (P4) intravaginal device (CIDR) on Day 23 after timed artificial insemination on cumulative pregnancy and embryonic losses in CIDR-GnRH synchronized Nili-Ravi buffaloes.

PubMed

Arshad, Usman; Qayyum, Arslan; Hassan, Mubbashar; Husnain, Ali; Sattar, Abdul; Ahmad, Nasim

2017-11-01

The objective of the present study was to determine the effect of resynchronization on Day 23 with either GnRH or P4 (controlled internal drug release device containing progesterone; CIDR) on pregnancy rate, cumulative pregnancy, and embryonic and fetal losses in CIDR-GnRH synchronized Nili-Ravi buffaloes. Buffaloes (n = 181) of mixed parity, lactating, 181 ± 73 days postpartum, a body condition score (BCS) of 3.2 ± 0.5 (scale of 1-5), and 450-600 kg weight were subjected to synchronization and resynchronization. All buffaloes received CIDR on Day -9.5. In addition, GnRH was injected 36 h after CIDR removal, and timed artificial insemination (TAI) was performed 18 h later (Day 0). On Day 23, buffaloes were randomly assigned to receive one of the following treatments: 1) CON (n = 63), 2) P4 (n = 55), and 3) GnRH (n = 63) for resynchronization (2nd AI). Pregnancy rate, and embryonic and fetal losses were monitored by serial ultrasonography on Days 30, 45, 60, and 90 after synchronization (1st TAI), respectively. The pregnancy rate in GnRH-treated buffaloes remained significantly and consistently higher (P < 0.05) than in the CON group at Days 30, 45, 60, and 90 after 1st TAI. Based on the pregnancy diagnosis, on Day 30 post 1st TAI, buffaloes that remained non-pregnant in the CON, P4, and GnRH groups received: 1) Artificial insemination on detected estrus (AIDE; n = 37), 2) CIDR-GnRH protocol (CIDR; n = 27), and 3) Ovsynch protocol (OVS; n = 23), respectively. The pregnancy rate in resynchronized buffaloes did not differ (P > 0.05) between the OVS and CIDR groups; whereas the, cumulative pregnancy rate in GnRH + OVS buffaloes (81%) after 1st and 2 nd AI when determined on Day 64 was higher (P < 0.05) than that in CON + AIDE (59%) buffaloes. The embryonic losses were significantly lower (P < 0.05) in GnRH-treated (18%) buffaloes, than in CON (42%) buffaloes on Day 45 post 1st TAI. Fetal losses were fewer and did not differ (P > 0.05) due to treatments on Day 60 or 90 post 1st AI. In conclusion, 1) the pregnancy rate and cumulative pregnancy rate in GnRH-treated buffaloes were higher than in CON buffaloes on Day 64 after synchronization and resynchronization, and 2) embryonic and fetal losses were lower in GnRH-treated buffaloes than in CON buffaloes when determined from Day 31-90 post 1st TAI. Copyright © 2017 Elsevier Inc. All rights reserved.

A new EEG synchronization strength analysis method: S-estimator based normalized weighted-permutation mutual information.

PubMed

Cui, Dong; Pu, Weiting; Liu, Jing; Bian, Zhijie; Li, Qiuli; Wang, Lei; Gu, Guanghua

2016-10-01

Synchronization is an important mechanism for understanding information processing in normal or abnormal brains. In this paper, we propose a new method called normalized weighted-permutation mutual information (NWPMI) for double variable signal synchronization analysis and combine NWPMI with S-estimator measure to generate a new method named S-estimator based normalized weighted-permutation mutual information (SNWPMI) for analyzing multi-channel electroencephalographic (EEG) synchronization strength. The performances including the effects of time delay, embedding dimension, coupling coefficients, signal to noise ratios (SNRs) and data length of the NWPMI are evaluated by using Coupled Henon mapping model. The results show that the NWPMI is superior in describing the synchronization compared with the normalized permutation mutual information (NPMI). Furthermore, the proposed SNWPMI method is applied to analyze scalp EEG data from 26 amnestic mild cognitive impairment (aMCI) subjects and 20 age-matched controls with normal cognitive function, who both suffer from type 2 diabetes mellitus (T2DM). The proposed methods NWPMI and SNWPMI are suggested to be an effective index to estimate the synchronization strength. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influence of Dexamethasone on Some Reproductive Hormones and Uterine Progesterone Receptor Localization in Pregnant Yankasa Sheep in Semiarid Zones of Nigeria.

PubMed

Yahi, Dauda; Ojo, Nicholas Adetayo; Mshelia, Gideon Dauda

2017-01-01

Dexamethasone is widely used in both veterinary and human medical practices. However, it seems to cause some deleterious effects on pregnancy probably by causing changes in the reproductive hormone levels and their corresponding receptor concentrations. This study investigated the effects of dexamethasone on these parameters. Twenty healthy adult Yankasa sheep comprising 18 ewes and 2 rams were used for this study. Pregnancies were achieved by natural mating after estrus synchronization. Dexamethasone was administered at 0.25 mg/kg body weight on days 1, 3, and 5 during first trimester; days 51, 53, and 55 during second trimester; and days 101, 103, and 105 during the third trimester. Blood samples were collected biweekly for hormonal assay. Uterine biopsies were harvested through caesarean section for immunohistochemical analysis. Results showed that dexamethasone significantly ( p < 0.05) decreased progesterone concentrations and caused abortion in Yankasa sheep but had no significant ( p > 0.05) effect on estrogen, while progesterone receptors (PR) were upregulated. The abortion could probably be due to decreased progesterone concentrations as a consequence of the adverse effects on placenta. The PR upregulation may be a compensatory mechanism to increase progesterone sensitivity. It was concluded that dexamethasone should not be used in advanced pregnancy in Yankasa sheep.

Influence of Dexamethasone on Some Reproductive Hormones and Uterine Progesterone Receptor Localization in Pregnant Yankasa Sheep in Semiarid Zones of Nigeria

PubMed Central

Ojo, Nicholas Adetayo; Mshelia, Gideon Dauda

2017-01-01

Dexamethasone is widely used in both veterinary and human medical practices. However, it seems to cause some deleterious effects on pregnancy probably by causing changes in the reproductive hormone levels and their corresponding receptor concentrations. This study investigated the effects of dexamethasone on these parameters. Twenty healthy adult Yankasa sheep comprising 18 ewes and 2 rams were used for this study. Pregnancies were achieved by natural mating after estrus synchronization. Dexamethasone was administered at 0.25 mg/kg body weight on days 1, 3, and 5 during first trimester; days 51, 53, and 55 during second trimester; and days 101, 103, and 105 during the third trimester. Blood samples were collected biweekly for hormonal assay. Uterine biopsies were harvested through caesarean section for immunohistochemical analysis. Results showed that dexamethasone significantly (p < 0.05) decreased progesterone concentrations and caused abortion in Yankasa sheep but had no significant (p > 0.05) effect on estrogen, while progesterone receptors (PR) were upregulated. The abortion could probably be due to decreased progesterone concentrations as a consequence of the adverse effects on placenta. The PR upregulation may be a compensatory mechanism to increase progesterone sensitivity. It was concluded that dexamethasone should not be used in advanced pregnancy in Yankasa sheep. PMID:29181440

Studies on the ovarian motility of small laboratory rodents.

PubMed

Gimeno, M F; Gimeno, A L

1975-01-01

Guinea pig ovaries were isolated and immersed in Krebs-Ringer bicarbonate solution, gassed with carbogen and added with glucose as the substrate. The experiments were carried out at 37 degrees C and the preparations were subjected to a basal tension of 500 mg. The spontaneous motility (contractile tension and frequency) of guinea pig ovaries obtained in late proestrus was significantly greater than that of the estrus or early proestrus. The influence of oxytocin on ovarian motility was significantly more marked in late proestrus than in estrus or early proestrus. Both the spontaneous and induced mortility of guinea pig ovaries are augmented in the immediate prevoulatory moment. In isolated rat ovaries, the isometric contractile tension and the frequency of contractions increased as the estral cycle progressed. During late proestrus, left ovaries had a contractile activity of greater intensity and frequency than the right ones, whereas during early proestrus the magnitudes were comparable. Oxytocin elicited greater responses in left than right ovaries of the late proestrus, the effect becoming similar in estrus and early proestrus. Rat ovaries obtained immediately before ovulation are specifically sensitized to the influence of oxytocin and not to other smooth muscle stimulants.

Leptospirosis is strongly associated to estrus repetition on cattle.

PubMed

Libonati, H A; Santos, G B; Souza, G N; Brandão, F Z; Lilenbaum, W

2018-05-02

Although prevalent, the exact impact of infectious diseases on reproductive failures remains to be determined. Among them, leptospirosis has commonly been reported as cause of abortions on outbreaks. Nevertheless, the majority of the animals present a chronic, silent form of the disease, which is characterized by low reproductive efficiency and is frequently neglected. In that context, we conducted a study that aims to estimate the impact of chronic leptospirosis on reproductive disorders on cattle. A total of 25 different dairy herds with history of reproductive losses from Rio de Janeiro, Brazil, were selected. From each herd, a questionnaire was applied and sera from 20 cows were randomly tested for leptospirosis (totaling 500 cows). Chi-square was performed to estimate the association of seroreactivity with reproductive disorders. A total of 32% of the herds were positive, all of them against serogroup Sejroe. Estrus repetition was the most important reported reproductive problem and it was strongly associated to seroreactivity against leptospirosis. Besides, specific vaccination against leptospirosis was an important protection factor against that disorder. In conclusion, control programs including, but not limited to, vaccines must be implemented on those herds in order to reduce reproductive losses, particularly estrus repetition.

Continuous contact with females in estrus throughout the year enhances testicular activity and improves seminal traits of male goats.

PubMed

Giriboni, Julia; Lacuesta, Lorena; Ungerfeld, Rodolfo

2017-01-01

The "female effect" consists in the stimulation of males' reproductive activity by different signals emitted by females. This stimulation leads to endocrine and behavioral changes that may modify the seasonal pattern of male ruminants. The aims of this experiment were (1) to describe the local reproductive seasonal pattern of Gabon bucks and (2) to determine if continuous chemical, auditory, and visual contact with does in estrus enhances bucks' testicular activity and improves seminal traits throughout the year and modify their seasonal pattern. We used 16 adult Gabon bucks assigned to two experimental groups: nine bucks remained continuously isolated from females (isolated bucks, group IB) and seven bucks were in continuous chemical, auditory, and visual contact through a fence line with does in estrus (stimulated bucks, group SB). During 13 months, scrotal circumference and testosterone concentration were measured weekly and testicular echogenicity was measured every 2 weeks. Also, sperm motility mass and percentage of abnormal spermatozoa were determined, and sperm concentration and total number of motile spermatozoa were calculated every 2 weeks. Testicular echogenicity was greater in IB than that in SB bucks (P < 0.0001), but there were no differences in scrotal circumference. Overall, testosterone concentration was greater in IB than that in SB bucks (P = 0.04), but from late winter to mid-summer, when testosterone concentration presented basal concentrations, SB bucks had greater values than IB bucks (P = 0.004). Sperm concentration (P = 0.05) and sperm mass motility (P = 0.01) were greater in SB than that in IB bucks, and the total number of progressive motile spermatozoa tended to be greater in SB than in that IB bucks (P = 0.1). The percentage of abnormal spermatozoa was lower in SB than in IB bucks in several time points (P < 0.0001). Testicular and seminal traits were better from the end of the spring until mid-autumn. We concluded that does in estrus stimulated bucks' testicular activity, including better seminal quality and a greater increase of testicular fluid content than bucks isolated from females. However, the general seasonal pattern was not modified by stimulation with does in estrus. Copyright © 2016 Elsevier Inc. All rights reserved.

Prostaglandin F2α 7 d prior to initiation of the 7-d CO-synch + CIDR protocol failed to enhance estrus response and pregnancy rates in beef heifers.

PubMed

Oosthuizen, Nicola; Canal, Luara B; Fontes, Pedro L P; Sanford, Carla D; DiLorenzo, Nicolas; Dahlen, Carl R; Seidel, George E; Lamb, G Cliff

2018-04-14

To determine the effects of administration of 25 mg of PGF2α 7 d prior to the initiation of the 7-d CO-Synch + controlled internal drug release (CIDR) fixed-time AI (TAI) protocol, 985 Bos taurus beef heifers were enrolled in a completely randomized design at 9 locations from April to July of 2016. Within location, all heifers were randomly assigned to 1 of 2 treatments: 1) CONTROL (n = 496); 100 µg injection of GnRH and a CIDR insert for 7 d [day 7], administration of 25 mg of PGF2α at CIDR removal [day 0], followed by a second injection of GnRH and TAI 54 ± 2 h later; or 2) PRESYNCH (n = 489); same as CONTROL but heifers received an additional injection of 25 mg of PGF2α 7 d prior [day 14] to CIDR insertion. Estrous detection patches were applied to all heifers on day 14 and were evaluated for estrual activity on day 7. Similarly, estrus alert patches were placed on all heifers on day 0 and evaluated for estrual activity at the time of TAI. Pregnancy was diagnosed via transrectal ultrasonography between 35 and 55 d after TAI. The percentage of heifers exhibiting estrus between days 14 and 7 was greater (P < 0.001) for the PRESYNCH (70.1 ± 2.4%) than the CONTROL (41.1 ± 2.3%) treatment, whereas the percentage of heifers exhibiting estrus between day 0 and TAI was greater (P < 0.001) for the CONTROL (55.6 ± 2.4%) than the PRESYNCH (39.7 ± 2.5%) treatment. Estrus response rates differed (P < 0.001) among locations. Pregnancy rates to TAI differed (P = 0.023) among locations; however, they did not differ (P = 0.739) between CONTROL and PRESYNCH treatments (45.4 ± 2.5 vs. 43.2 ± 2.5%, respectively). Final breeding season pregnancy rates did not differ (P = 0.811) between treatments. Therefore, an injection of PGF2α 7 d prior to initiation of the 7-d CO-Synch + CIDR protocol failed to improve pregnancy rates to TAI in replacement beef heifers.

RUN LENGTH SYNCHRONIZATION TECHNIQUES

DTIC Science & Technology

An important aspect of digital communications is the problem of determining efficient methods for acquiring block synchronization . In this paper we...utilizes an N-digit sync sequence as prefix to the data blocks. The results of this study show that this technique is a practical method for acquiring block synchronization .

Review of available synchronization and time distribution techniques

NASA Technical Reports Server (NTRS)

Hall, R. G.; Lieberman, T. N.; Stone, R. R.

1974-01-01

The methods of synchronizing precision clocks will be reviewed placing particular attention to the simpler techniques, their accuracies, and the approximate cost of equipment. The more exotic methods of synchronization are discussed in lesser detail. The synchronization techniques that will be covered will include satellite dissemination, communication and navigation transmissions via VLF, LF, HF, UHF and microwave as well as commercial and armed forces television. Portable clock trips will also be discussed.

Serum profile of cytokines interferon gamma and interleukin-10 in ewes subjected to artificial insemination by cervical retraction.

PubMed

Alvares, C T G; Cruz, J F; Romano, C C; Brandão, F Z

2016-04-15

This study evaluated the influence of artificial insemination (AI) by cervical retraction (CRI) on serum levels of interferon gamma (IFNγ) and interleukin-10 (IL-10) in ewes. Synchronized pluriparous Santa Inês ewes were subjected to natural mating (NM, n = 8) and AI, which was performed for a fixed time (55 ± 1 hour) by CRI (n = 8) or laparoscopy (n = 8). Ewes were classified as pregnant, with return to estrus (RE) or with embryonic loss (EL). Blood samples were collected on Day 0, Day 3, Day 5, Day 12, and Day 17 (Day 0 = AI/NM) for progesterone dosage and cytokines were quantified from Day 0 to Day 12. Progesterone levels were constant, except for a decrease in ewes with RE at Day 17 (P < 0.05). Regardless of the reproductive method used, there was no difference in the IFNγ and IL-10 levels at any time, with averages of 642.1, 713.2, and 741.2 pg/mL for IFNγ and 667.1, 616.8, and 721.1 pg/mL for IL-10 when using CRI, laproscopy, and NM, respectively. Regarding the physiological status, ewes with EL had lower serum levels of IFNγ and IL-10 than pregnant ewes and ewes with RE, regardless of the reproductive method used, with averages of 769.1, 714.9, and 555.7 pg/mL for IFNγ and 713.8, 699.3, and 578.7 pg/mL for IL-10 in pregnant ewes, ewes with RE and EL, respectively (P < 0.01). In conclusion, AI by CRI in Santa Inês ewes does not alter the profile of serum cytokines IFNγ and IL-10 and does not induce an inflammatory reaction that can compromise pregnancy. Copyright © 2016 Elsevier Inc. All rights reserved.

Dynamical inference: where phase synchronization and generalized synchronization meet.

PubMed

Stankovski, Tomislav; McClintock, Peter V E; Stefanovska, Aneta

2014-06-01

Synchronization is a widespread phenomenon that occurs among interacting oscillatory systems. It facilitates their temporal coordination and can lead to the emergence of spontaneous order. The detection of synchronization from the time series of such systems is of great importance for the understanding and prediction of their dynamics, and several methods for doing so have been introduced. However, the common case where the interacting systems have time-variable characteristic frequencies and coupling parameters, and may also be subject to continuous external perturbation and noise, still presents a major challenge. Here we apply recent developments in dynamical Bayesian inference to tackle these problems. In particular, we discuss how to detect phase slips and the existence of deterministic coupling from measured data, and we unify the concepts of phase synchronization and general synchronization. Starting from phase or state observables, we present methods for the detection of both phase and generalized synchronization. The consistency and equivalence of phase and generalized synchronization are further demonstrated, by the analysis of time series from analog electronic simulations of coupled nonautonomous van der Pol oscillators. We demonstrate that the detection methods work equally well on numerically simulated chaotic systems. In all the cases considered, we show that dynamical Bayesian inference can clearly identify noise-induced phase slips and distinguish coherence from intrinsic coupling-induced synchronization.

System and method to allow a synchronous motor to successfully synchronize with loads that have high inertia and/or high torque

DOEpatents

Melfi, Michael J.

2015-10-20

A mechanical soft-start type coupling is used as an interface between a line start, synchronous motor and a heavy load to enable the synchronous motor to bring the heavy load up to or near synchronous speed. The soft-start coupling effectively isolates the synchronous motor from the load for enough time to enable the synchronous motor to come up to full speed. The soft-start coupling then brings the load up to or near synchronous speed.

Robust pre-specified time synchronization of chaotic systems by employing time-varying switching surfaces in the sliding mode control scheme

NASA Astrophysics Data System (ADS)

Khanzadeh, Alireza; Pourgholi, Mahdi

2016-08-01

In the conventional chaos synchronization methods, the time at which two chaotic systems are synchronized, is usually unknown and depends on initial conditions. In this work based on Lyapunov stability theory a sliding mode controller with time-varying switching surfaces is proposed to achieve chaos synchronization at a pre-specified time for the first time. The proposed controller is able to synchronize chaotic systems precisely at any time when we want. Moreover, by choosing the time-varying switching surfaces in a way that the reaching phase is eliminated, the synchronization becomes robust to uncertainties and exogenous disturbances. Simulation results are presented to show the effectiveness of the proposed method of stabilizing and synchronizing chaotic systems with complete robustness to uncertainty and disturbances exactly at a pre-specified time.

In vivo and in vitro study of the function of the left and right bovine ovaries.

PubMed

Karamishabankareh, Hamed; Hajarian, Hadi; Shahsavari, Mohammadhamed; Moradinejad, Ruhollah

2015-09-15

Inequality in function of the left and right bovine ovaries and uterine horns was evaluated in two separate experiments. In the first experiment (in vivo), the relationship between the left and right ovarian activities and reproductive indices was evaluated. Therefore, the total number of 1284 randomly chosen lactating dairy cows were examined from Day 50 to 60 postpartum, and according to the presence of an active CL on the ovaries, they were divided into 502 LCL3-cows and 782 RCL3-cows (cows with an active CL on the left [L] or right [R] ovary, respectively). To induce estrus synchronization and investigate the effects of PGF2α administration on the incidence of estrus in both LCL3-cows and RCL3-cows, the cows were treated with one luteolytic dose of PGF2α and were inseminated after observed estrus (via visual observation lasting at least 30 minutes three times a day). To investigate the effects of side of ovulation at the time of PGF2α administration on reproductive parameters, pregnancy diagnosis was performed 28 days after insemination (using ultrasound) and 42 days after insemination (using transrectal palpation). The results showed that the percentage of the RCL3-cows was greater than the LCL3-cows (60.9% vs. 39.1%, respectively). Furthermore, ovulations switching from the left to right ovary in two successive ovulations were greater than those that switched from the right to left ovary. On the other hand, the sex ratio (male percentage) in the right uterine horn was greater than that of the left one. In the second experiment (in vitro), the developmental potential of bovine oocytes derived from the left (L-oocytes) and right (R-oocytes) ovaries after in vitro embryo production and heterogeneity in the developmental competence of L-oocytes and R-oocytes using the brilliant cresyl blue staining test as a selection criterion were evaluated. Results of the in vitro experiment showed that the percentage of cleavage and blastocyst rate of R-oocytes were greater (P < 0.001) than those of L-oocytes. Moreover, it appears that the side of ovaries had greater effects on the developmental competence of oocytes than other factors associated with heterogeneity in the developmental competence of oocytes, which can be detected by the brilliant cresyl blue test. In conclusion, the results of the in vivo study confirmed the observations in previous studies in which the right ovarian response (distribution of ovulation) was superior to that of the left ones. Interestingly, the in vitro experiments for the first time clearly showed that more ovulation on the right side is not the only reason for this unequal activity. In fact, in cattle, the greater developmental potential of oocytes originating from right ovaries may cause superior activity of the right side, and the effect is even higher than the differences in ovulation response between the left and right ovaries. Copyright © 2015 Elsevier Inc. All rights reserved.

System and method for clock synchronization and position determination using entangled photon pairs

NASA Technical Reports Server (NTRS)

Shih, Yanhua (Inventor)

2010-01-01

A system and method for clock synchronization and position determination using entangled photon pairs is provided. The present invention relies on the measurement of the second order correlation function of entangled states. Photons from an entangled photon source travel one-way to the clocks to be synchronized. By analyzing photon registration time histories generated at each clock location, the entangled states allow for high accuracy clock synchronization as well as high accuracy position determination.

Is whole-culture synchronization biology's 'perpetual-motion machine'?

PubMed

Cooper, Stephen

2004-06-01

Whole-culture or batch synchronization cannot, in theory, produce a synchronized culture because it violates a fundamental law that proposes that no batch treatment can alter the cell-age order of a culture. In analogy with the history of perpetual-motion machines, it is suggested that the study of these whole-culture 'synchronization' methods might lead to an understanding of general biological principles even though these methods cannot be used to study the normal cell cycle.

Cluster-Based Maximum Consensus Time Synchronization for Industrial Wireless Sensor Networks.

PubMed

Wang, Zhaowei; Zeng, Peng; Zhou, Mingtuo; Li, Dong; Wang, Jintao

2017-01-13

Time synchronization is one of the key technologies in Industrial Wireless Sensor Networks (IWSNs), and clustering is widely used in WSNs for data fusion and information collection to reduce redundant data and communication overhead. Considering IWSNs' demand for low energy consumption, fast convergence, and robustness, this paper presents a novel Cluster-based Maximum consensus Time Synchronization (CMTS) method. It consists of two parts: intra-cluster time synchronization and inter-cluster time synchronization. Based on the theory of distributed consensus, the proposed method utilizes the maximum consensus approach to realize the intra-cluster time synchronization, and adjacent clusters exchange the time messages via overlapping nodes to synchronize with each other. A Revised-CMTS is further proposed to counteract the impact of bounded communication delays between two connected nodes, because the traditional stochastic models of the communication delays would distort in a dynamic environment. The simulation results show that our method reduces the communication overhead and improves the convergence rate in comparison to existing works, as well as adapting to the uncertain bounded communication delays.

Cluster-Based Maximum Consensus Time Synchronization for Industrial Wireless Sensor Networks †

PubMed Central

Wang, Zhaowei; Zeng, Peng; Zhou, Mingtuo; Li, Dong; Wang, Jintao

2017-01-01

Time synchronization is one of the key technologies in Industrial Wireless Sensor Networks (IWSNs), and clustering is widely used in WSNs for data fusion and information collection to reduce redundant data and communication overhead. Considering IWSNs’ demand for low energy consumption, fast convergence, and robustness, this paper presents a novel Cluster-based Maximum consensus Time Synchronization (CMTS) method. It consists of two parts: intra-cluster time synchronization and inter-cluster time synchronization. Based on the theory of distributed consensus, the proposed method utilizes the maximum consensus approach to realize the intra-cluster time synchronization, and adjacent clusters exchange the time messages via overlapping nodes to synchronize with each other. A Revised-CMTS is further proposed to counteract the impact of bounded communication delays between two connected nodes, because the traditional stochastic models of the communication delays would distort in a dynamic environment. The simulation results show that our method reduces the communication overhead and improves the convergence rate in comparison to existing works, as well as adapting to the uncertain bounded communication delays. PMID:28098750

A synchronization method for wireless acquisition systems, application to brain computer interfaces.

PubMed

Foerster, M; Bonnet, S; van Langhenhove, A; Porcherot, J; Charvet, G

2013-01-01

A synchronization method for wireless acquisition systems has been developed and implemented on a wireless ECoG recording implant and on a wireless EEG recording helmet. The presented algorithm and hardware implementation allow the precise synchronization of several data streams from several sensor nodes for applications where timing is critical like in event-related potential (ERP) studies. The proposed method has been successfully applied to obtain visual evoked potentials and compared with a reference biosignal amplifier. The control over the exact sampling frequency allows reducing synchronization errors that will otherwise accumulate during a recording. The method is scalable to several sensor nodes communicating with a shared base station.

Method and system for downhole clock synchronization

DOEpatents

Hall, David R.; Bartholomew, David B.; Johnson, Monte; Moon, Justin; Koehler, Roger O.

2006-11-28

A method and system for use in synchronizing at least two clocks in a downhole network are disclosed. The method comprises determining a total signal latency between a controlling processing element and at least one downhole processing element in a downhole network and sending a synchronizing time over the downhole network to the at least one downhole processing element adjusted for the signal latency. Electronic time stamps may be used to measure latency between processing elements. A system for electrically synchronizing at least two clocks connected to a downhole network comprises a controlling processing element connected to a synchronizing clock in communication over a downhole network with at least one downhole processing element comprising at least one downhole clock. Preferably, the downhole network is integrated into a downhole tool string.

A dynamical systems approach for estimating phase interactions between rhythms of different frequencies from experimental data

PubMed Central

Goto, Takahiro; Aoyagi, Toshio

2018-01-01

Synchronization of neural oscillations as a mechanism of brain function is attracting increasing attention. Neural oscillation is a rhythmic neural activity that can be easily observed by noninvasive electroencephalography (EEG). Neural oscillations show the same frequency and cross-frequency synchronization for various cognitive and perceptual functions. However, it is unclear how this neural synchronization is achieved by a dynamical system. If neural oscillations are weakly coupled oscillators, the dynamics of neural synchronization can be described theoretically using a phase oscillator model. We propose an estimation method to identify the phase oscillator model from real data of cross-frequency synchronized activities. The proposed method can estimate the coupling function governing the properties of synchronization. Furthermore, we examine the reliability of the proposed method using time-series data obtained from numerical simulation and an electronic circuit experiment, and show that our method can estimate the coupling function correctly. Finally, we estimate the coupling function between EEG oscillation and the speech sound envelope, and discuss the validity of these results. PMID:29337999

Ovarian follicular dynamics and plasma steroid concentrations are not significantly different in ewes given intravaginal sponges containing either 20 or 40 mg of fluorogestone acetate.

PubMed

Letelier, C A; Contreras-Solis, I; García-Fernández, R A; Ariznavarreta, C; Tresguerres, J A F; Flores, J M; Gonzalez-Bulnes, A

2009-03-01

Although various progestagens are often used to induce and synchronize estrus and ovulation in ruminants, concerns regarding residues are the impetus to develop alternative approaches, including reduced doses of progestagens. Therefore, the objective was to determine whether ovarian function was affected by halving the dose of fluorogestone acetate in intravaginal sponges for synchronizing ovulation in sheep during the physiologic breeding season. Twenty Manchega ewes, 4-6-year-old, were randomly allocated to receive an intravaginal sponge containing either 20mg (P20, n=10) or 40 mg of fluorogestone acetate (P40, n=10). Cloprostenol (125 microg) was given at sponge insertion, and all sponges were removed after 6d. Ovarian follicular dynamics (monitored by daily ultrasonography) and other aspects of ovarian function did not differ significantly between the two groups. Ovulatory follicles (OF) grew at a similar growth rate (r=0.62; P<0.001), with comparable initial and maximum diameters (4.2+/-0.4 to 6.0+/-0.3mm in P20 vs. 4.6+/-0.6 to 5.7+/-0.2 mm in P40, mean+/-S.E.M.). Plasma estradiol concentrations (determined once daily) increased linearly during the 72 h interval after sponge removal (1.3+/-0.1 to 3.3+/-0.1 pg/mL for P20, P<0.005 and 1.4+/-0.1 to 3.1+/-0.2 pg/mL for P40, P<0.005). Ten days after sponge removal, ovulation rates (1.2+/-0.2 for P20 and 1.4+/-0.3 for P40), and plasma progesterone concentrations (3.8+/-0.35 ng/mL for P20 and 3.9+/-0.38 ng/mL for P40) were similar. In conclusion, reducing the dose of fluorogestone acetate from 40 to 20mg did not affect significantly ovarian follicular dynamics or other aspects of ovarian function.

Pregnancy success of lactating Holstein cows after a single administration of a sustained-release formulation of recombinant bovine somatotropin

PubMed Central

Bell, A; Rodríguez, OA; de Castro e Paula, LA; Padua, MB; Hernández-Cerón, J; Gutiérrez, CG; De Vries, A; Hansen, PJ

2008-01-01

Background Results regarding the use of bovine somatotropin for enhancing fertility in dairy cattle are variable. Here, the hypothesis was tested that a single injection of a sustained-release preparation of bovine somatotropin (bST) during the preovulatory period would improve pregnancy success of lactating dairy cows at first service. Results The first experiment was conducted in a temperate region of Mexico. Cows inseminated following natural estrus or timed artificial insemination were given a single injection of bST or a placebo injection at insemination (n = 100 cows per group). There was no significant difference between bST and control groups in the proportion of inseminated cows diagnosed pregnant (29 vs 31% pregnant). The second experiment was performed during heat stress in Florida. Cows were subjected to an ovulation synchronization regimen for first insemination. Cows treated with bST received a single injection at 3 days before insemination. Controls received no additional treatment. As expected, bST did not increase vaginal temperature. Treatment with bST did not significantly increase the proportion of inseminated cows diagnosed pregnant although it was numerically greater for the bST group (24.2% vs 17.8%, 124–132 cows per group). There was a tendency (p = 0.10) for a smaller percent of control cows to have high plasma progesterone concentrations (≥ 1 ng/ml) at Day 7 after insemination than for bST-treated cows (72.6 vs 81.1%). When only cows that were successfully synchronized were considered, the magnitude of the absolute difference in the percentage of inseminated cows that were diagnosed pregnant between bST and control cows was reduced (24.8 vs 22.4% pregnant for bST and control). Conclusion Results failed to indicate a beneficial effect of bST treatment on fertility of lactating dairy cows. PMID:18582389

Complete characterization of the stability of cluster synchronization in complex dynamical networks.

PubMed

Sorrentino, Francesco; Pecora, Louis M; Hagerstrom, Aaron M; Murphy, Thomas E; Roy, Rajarshi

2016-04-01

Synchronization is an important and prevalent phenomenon in natural and engineered systems. In many dynamical networks, the coupling is balanced or adjusted to admit global synchronization, a condition called Laplacian coupling. Many networks exhibit incomplete synchronization, where two or more clusters of synchronization persist, and computational group theory has recently proved to be valuable in discovering these cluster states based on the topology of the network. In the important case of Laplacian coupling, additional synchronization patterns can exist that would not be predicted from the group theory analysis alone. Understanding how and when clusters form, merge, and persist is essential for understanding collective dynamics, synchronization, and failure mechanisms of complex networks such as electric power grids, distributed control networks, and autonomous swarming vehicles. We describe a method to find and analyze all of the possible cluster synchronization patterns in a Laplacian-coupled network, by applying methods of computational group theory to dynamically equivalent networks. We present a general technique to evaluate the stability of each of the dynamically valid cluster synchronization patterns. Our results are validated in an optoelectronic experiment on a five-node network that confirms the synchronization patterns predicted by the theory.

Analysis and compensation of synchronous measurement error for multi-channel laser interferometer

NASA Astrophysics Data System (ADS)

Du, Shengwu; Hu, Jinchun; Zhu, Yu; Hu, Chuxiong

2017-05-01

Dual-frequency laser interferometer has been widely used in precision motion system as a displacement sensor, to achieve nanoscale positioning or synchronization accuracy. In a multi-channel laser interferometer synchronous measurement system, signal delays are different in the different channels, which will cause asynchronous measurement, and then lead to measurement error, synchronous measurement error (SME). Based on signal delay analysis of the measurement system, this paper presents a multi-channel SME framework for synchronous measurement, and establishes the model between SME and motion velocity. Further, a real-time compensation method for SME is proposed. This method has been verified in a self-developed laser interferometer signal processing board (SPB). The experiment result showed that, using this compensation method, at a motion velocity 0.89 m s-1, the max SME between two measuring channels in the SPB is 1.1 nm. This method is more easily implemented and applied to engineering than the method of directly testing smaller signal delay.

Frame Synchronization Without Attached Sync Markers

NASA Technical Reports Server (NTRS)

Hamkins, Jon

2011-01-01

We describe a method to synchronize codeword frames without making use of attached synchronization markers (ASMs). Instead, the synchronizer identifies the code structure present in the received symbols, by operating the decoder for a handful of iterations at each possible symbol offset and forming an appropriate metric. This method is computationally more complex and doesn't perform as well as frame synchronizers that utilize an ASM; nevertheless, the new synchronizer acquires frame synchronization in about two seconds when using a 600 kbps software decoder, and would take about 15 milliseconds on prototype hardware. It also eliminates the need for the ASMs, which is an attractive feature for short uplink codes whose coding gain would be diminished by the overheard of ASM bits. The lack of ASMs also would simplify clock distribution for the AR4JA low-density parity-check (LDPC) codes and adds a small amount to the coding gain as well (up to 0.2 dB).

Finding Major Patterns of Aging Process by Data Synchronization

NASA Astrophysics Data System (ADS)

Miyano, Takaya; Tsutsui, Takako

We developed a method for extracting feature patterns from multivariate data using a network of coupled phase oscillators subject to an analogue of the Kuramoto model for collective synchronization. Our method may be called data synchronization. We applied data synchronization to the care-needs-certification data, provided by Otsu City as a historical old city near Kyoto City, in the Japanese public long-term care insurance program to find the trend of the major patterns of the aging process for elderly people needing nursing care.

Corpus luteum function following single and double ovulation during estrous cycle in Sanjabi ewes.

PubMed

Shabankareh, H Karami; Habibizad, J; Torki, M

2009-09-01

This study compared the effect of double and single ovulation on serum progesterone concentrations and luteal characteristics in Sanjabi ewes at different days of the estrous cycle. The estrous cycles of 197 Sanjabi ewes were synchronized by a 12-day treatment with intravaginal sponges (Chronogest). Estrus was detected in 144 ewes 27-39 h after sponge removal. Daily blood samples were taken every morning and analyzed for serum progesterone (P4). Ewes were then transported to a local abattoir, where nine ewes were slaughtered on each experimental day (days 1-16 after estrus) for ovary collection. The ovarian follicles were measured and categorized by size (very small <2mm; small 2-3.5mm; medium 3.5-5mm; large >5mm). On each slaughter day, the number of corpora lutea per ewe was classified as single and double ovulation. The results show that the effect of dominant follicles was less during the mid-luteal phase. Ovulation rate of right, left and both ovaries were (54.9%), (23.6%) and (21.5%), respectively. The incidence of double ovulations was 40.2%. In the case of ewes exhibiting double ovulation, 46.6% occurred unilateral (ewes exhibited both ovulations on the right ovary); whereas 53.4% occurred bilateral (ewes exhibited ovulations on the right and left ovaries). Unilateral double ovulation was not observed in the left ovary. The right ovary appeared to play a significantly greater role in ewes showing single and double ovulations than the left ovary (P<0.05). Serum progesterone concentration showed minimum and maximum levels of 0.29+/-0.15 and 5.51+/-0.75 ng/ml on days 16 and 11 post-estrous, respectively (P<0.001). The mean volume of individual corpus lutea in ewes with single ovulations was significantly higher than in ewes with double ovulations (P<0.01). However, the total volume of corpus lutea in ewes with single ovulation was significantly lower than in ewes with double ovulations in some days of estrous cycle (P<0.01). The serum progesterone concentration was significantly higher in double than single ovulating animals on days 1-16 of the estrous cycle (P<0.001). These results indicated a relatively high incidence of double ovulation in ewes associated with increasing total luteal volume and high circulating concentrations of progesterone.

Synchronization of EEG activity in patients with bipolar disorder

NASA Astrophysics Data System (ADS)

Panischev, O. Yu; Demin, S. A.; Muhametshin, I. G.; Demina, N. Yu

2015-12-01

In paper we apply the method based on the Flicker-Noise Spectroscopy (FNS) to determine the differences in frequency-phase synchronization of the cortical electroencephalographic (EEG) activities in patients with bipolar disorder (BD). We found that for healthy subjects the frequency-phase synchronization of EEGs from long-range electrodes was significantly better for BD patients. In BD patients a high synchronization of EEGs was observed only for short-range electrodes. Thus, the FNS is a simple graphical method for qualitative analysis can be applied to identify the synchronization effects in EEG activity and, probably, may be used for the diagnosis of this syndrome.

Systems and methods for self-synchronized digital sampling

NASA Technical Reports Server (NTRS)

Samson, Jr., John R. (Inventor)

2008-01-01

Systems and methods for self-synchronized data sampling are provided. In one embodiment, a system for capturing synchronous data samples is provided. The system includes an analog to digital converter adapted to capture signals from one or more sensors and convert the signals into a stream of digital data samples at a sampling frequency determined by a sampling control signal; and a synchronizer coupled to the analog to digital converter and adapted to receive a rotational frequency signal from a rotating machine, wherein the synchronizer is further adapted to generate the sampling control signal, and wherein the sampling control signal is based on the rotational frequency signal.

A review of recent studies on the mechanisms and analysis methods of sub-synchronous oscillation in wind farms

NASA Astrophysics Data System (ADS)

Wang, Chenggen; Zhou, Qian; Gao, Shuning; Luo, Jia; Diao, Junchao; Zhao, Haoran; Bu, Jing

2018-04-01

This paper reviews the recent studies of Sub-Synchronous Oscillation(SSO) in wind farms. Mechanisms and analysis methods are the main concerns of this article. A classification method including new types of oscillation occurred between wind farms and HVDC systems and oscillation caused by Permanent Magnet Synchronous Generators(PMSG) is proposed. Characteristics of oscillation analysis techniques are summarized.

Localization of synchronous cortical neural sources.

PubMed

Zerouali, Younes; Herry, Christophe L; Jemel, Boutheina; Lina, Jean-Marc

2013-03-01

Neural synchronization is a key mechanism to a wide variety of brain functions, such as cognition, perception, or memory. High temporal resolution achieved by EEG recordings allows the study of the dynamical properties of synchronous patterns of activity at a very fine temporal scale but with very low spatial resolution. Spatial resolution can be improved by retrieving the neural sources of EEG signal, thus solving the so-called inverse problem. Although many methods have been proposed to solve the inverse problem and localize brain activity, few of them target the synchronous brain regions. In this paper, we propose a novel algorithm aimed at localizing specifically synchronous brain regions and reconstructing the time course of their activity. Using multivariate wavelet ridge analysis, we extract signals capturing the synchronous events buried in the EEG and then solve the inverse problem on these signals. Using simulated data, we compare results of source reconstruction accuracy achieved by our method to a standard source reconstruction approach. We show that the proposed method performs better across a wide range of noise levels and source configurations. In addition, we applied our method on real dataset and identified successfully cortical areas involved in the functional network underlying visual face perception. We conclude that the proposed approach allows an accurate localization of synchronous brain regions and a robust estimation of their activity.

Effects of changes in photoperiod and temperature on the estrous cycle of a captive female giant panda (Ailuropoda melanoleuca).

PubMed

Tay, Trisha T N; Li, Desheng; Huang, Yan; Wang, Pengyan; Tahar, Tasha; Kawi, Josephine

2018-03-01

The female giant panda's estrus is known to be photoperiod sensitive, triggered by increasing day length. A pair of giant pandas was brought to Singapore in September 2012 and exposed to a constant temperature and photoperiod during the first 2 years. The female did not show any signs of estrus during that period. In November 2014, photoperiod and temperature were manipulated to simulate seasonal changes, to investigate the effects of environmental factors on the sexual behavior of the giant pandas. This paper documents the changes and observations carried out from 2012 to 2016, in the attempt to breed this vulnerable species. © 2018 Wiley Periodicals, Inc.

Enhanced Precision Time Synchronization for Wireless Sensor Networks

PubMed Central

Cho, Hyuntae; Kim, Jongdeok; Baek, Yunju

2011-01-01

Time synchronization in wireless sensor networks (WSNs) is a fundamental issue for the coordination of distributed entities and events. Nondeterministic latency, which may decrease the accuracy and precision of time synchronization can occur at any point in the network layers. Specially, random back-off by channel contention leads to a large uncertainty. In order to reduce the large nondeterministic uncertainty from channel contention, we propose an enhanced precision time synchronization protocol in this paper. The proposed method reduces the traffic needed for the synchronization procedure by selectively forwarding the packet. Furthermore, the time difference between sensor nodes increases as time advances because of the use of a clock source with a cheap crystal oscillator. In addition, we provide a means to maintain accurate time by adopting hardware-assisted time stamp and drift correction. Experiments are conducted to evaluate the performance of the proposed method, for which sensor nodes are designed and implemented. According to the evaluation results, the performance of the proposed method is better than that of a traditional time synchronization protocol. PMID:22164035

Enhanced precision time synchronization for wireless sensor networks.

PubMed

Cho, Hyuntae; Kim, Jongdeok; Baek, Yunju

2011-01-01

Time synchronization in wireless sensor networks (WSNs) is a fundamental issue for the coordination of distributed entities and events. Nondeterministic latency, which may decrease the accuracy and precision of time synchronization can occur at any point in the network layers. Specially, random back-off by channel contention leads to a large uncertainty. In order to reduce the large nondeterministic uncertainty from channel contention, we propose an enhanced precision time synchronization protocol in this paper. The proposed method reduces the traffic needed for the synchronization procedure by selectively forwarding the packet. Furthermore, the time difference between sensor nodes increases as time advances because of the use of a clock source with a cheap crystal oscillator. In addition, we provide a means to maintain accurate time by adopting hardware-assisted time stamp and drift correction. Experiments are conducted to evaluate the performance of the proposed method, for which sensor nodes are designed and implemented. According to the evaluation results, the performance of the proposed method is better than that of a traditional time synchronization protocol.

High performance frame synchronization for continuous variable quantum key distribution systems.

PubMed

Lin, Dakai; Huang, Peng; Huang, Duan; Wang, Chao; Peng, Jinye; Zeng, Guihua

2015-08-24

Considering a practical continuous variable quantum key distribution(CVQKD) system, synchronization is of significant importance as it is hardly possible to extract secret keys from unsynchronized strings. In this paper, we proposed a high performance frame synchronization method for CVQKD systems which is capable to operate under low signal-to-noise(SNR) ratios and is compatible with random phase shift induced by quantum channel. A practical implementation of this method with low complexity is presented and its performance is analysed. By adjusting the length of synchronization frame, this method can work well with large range of SNR values which paves the way for longer distance CVQKD.

Method for protecting an electric generator

DOEpatents

Kuehnle, Barry W.; Roberts, Jeffrey B.; Folkers, Ralph W.

2008-11-18

A method for protecting an electrical generator which includes providing an electrical generator which is normally synchronously operated with an electrical power grid; providing a synchronizing signal from the electrical generator; establishing a reference signal; and electrically isolating the electrical generator from the electrical power grid if the synchronizing signal is not in phase with the reference signal.

Calculating Synchronous Inductive Reactances of Contactless Machines When Magnetic Circuit is Saturated and of Machines with Superconducting Excitation Windings,

DTIC Science & Technology

The work studies the effect of magnetic circuit saturation on the synchronous inductive reactance of the armature. A practical method is given for...calculating synchronized parameters in saturating synchronized machines with additional clearances and machines with superconducting excitation windings.

The control gain region for synchronization in non-diffusively coupled complex networks

NASA Astrophysics Data System (ADS)

Gequn, Liu; Wenhui, Li; Huijie, Yang; Knowles, Gareth

2014-07-01

The control gain region for synchronization of non-diffusively coupled networks was studied with respect to three conditions: synchronization, synchronization in finite time, and synchronization in the minimum time. Based on cancellation control methodology and master stability function formalism, we found that a complete feasible control gain region may be bounded, unbounded, empty or a union of several bounded and unbounded regions, with a similar shape to the synchronized region. An interesting possibility emerged that a network could be synchronized by both negative and positive feedback control simultaneously. By bridging synchronizability and synchronizing response speeds with a settling time index, we have developed timed synchronized region (TSR) as a substitute for the classical synchronized region to study finite time synchronization. As for the last condition, a graphical method was developed to estimate control gain with the minimum synchronization time (CGMST). Each condition has examples provided for illustration and verification.

Alterations in dopamine system function across the estrous cycle of the MAM rodent model of schizophrenia.

PubMed

Perez, Stephanie M; Chen, Li; Lodge, Daniel J

2014-09-01

Clinical studies have reported differences in the incidence and severity of schizophrenia symptoms between male and female schizophrenia patients. Unfortunately, the cause of these differences is not currently known due, in part, to the fact that preclinical studies largely focus on male subjects. Dopamine neuron activity has been previously demonstrated to change across the estrous cycle, and may therefore be of relevance, as aberrant dopamine signaling is thought to underlie the positive symptoms of schizophrenia. Here we examine dopamine neuron activity across the estrous cycle in the MAM rodent model of schizophrenia. We demonstrate that the elevation in dopamine neuron activity, consistently observed in male MAM-treated rats, is most prominent during estrus and attenuated in met-estrus. Furthermore, this appears to be mediated, in part, by progesterone in the ventral hippocampus, as increases in dopamine neuron population activity (observed in estrus) were normalized by the intra-hippocampal administration of the progesterone receptor antagonist, mifepristone (but not the estrogen receptor antagonists, fulvestrant). Taken together, these data suggest that changes in dopamine system function occur across the estrous cycle in MAM-treated rats and may contribute to the differences in symptomatology between male and female schizophrenia patients. Copyright © 2014 Elsevier Ltd. All rights reserved.

Changes in the sexual behavior and testosterone levels of male rats in response to daily interactions with estrus females

PubMed Central

Shulman, Leanne M.; Spritzer, Mark D.

2014-01-01

Male rat sexual behavior has been intensively studied over the past 100 years, but few studies have examined how sexual behavior changes over the course of several days of interactions. In this experiment, adult male rats (n = 12) were given daily access to estrus females for 30 min per day for 15 consecutive days and control males did not interact with females. Ovariectomized females were induced into estrus with hormonal injections, and males interacted with a different female each day. The amount of sexual activity (mounts, intromissions, and ejaculations) was found to cycle with a period of approximately 4 days in most male rats. Additionally, blood was collected every other day following sexual interactions to assess serum testosterone levels. Testosterone was found to peak on the first day of interaction and then fell back to near the level of control rats that did not interact with females. Following the initial peak, testosterone concentrations fluctuated less in males exposed to females than in controls. Sexual activity was not found to predict testosterone concentration. We conclude that when male rats have daily sexual interactions, sexual behavior tends to show cyclic changes and testosterone is significantly elevated only on the first day of interactions. PMID:24813700

Flagellar Synchronization Is a Simple Alternative to Cell Cycle Synchronization for Ciliary and Flagellar Studies

PubMed Central

Dutta, Soumita

2017-01-01

ABSTRACT The unicellular green alga Chlamydomonas reinhardtii is an ideal model organism for studies of ciliary function and assembly. In assays for biological and biochemical effects of various factors on flagellar structure and function, synchronous culture is advantageous for minimizing variability. Here, we have characterized a method in which 100% synchronization is achieved with respect to flagellar length but not with respect to the cell cycle. The method requires inducing flagellar regeneration by amputation of the entire cell population and limiting regeneration time. This results in a maximally homogeneous distribution of flagellar lengths at 3 h postamputation. We found that time-limiting new protein synthesis during flagellar synchronization limits variability in the unassembled pool of limiting flagellar protein and variability in flagellar length without affecting the range of cell volumes. We also found that long- and short-flagella mutants that regenerate normally require longer and shorter synchronization times, respectively. By minimizing flagellar length variability using a simple method requiring only hours and no changes in media, flagellar synchronization facilitates the detection of small changes in flagellar length resulting from both chemical and genetic perturbations in Chlamydomonas. This method increases our ability to probe the basic biology of ciliary size regulation and related disease etiologies. IMPORTANCE Cilia and flagella are highly conserved antenna-like organelles that found in nearly all mammalian cell types. They perform sensory and motile functions contributing to numerous physiological and developmental processes. Defects in their assembly and function are implicated in a wide range of human diseases ranging from retinal degeneration to cancer. Chlamydomonas reinhardtii is an algal model system for studying mammalian cilium formation and function. Here, we report a simple synchronization method that allows detection of small changes in ciliary length by minimizing variability in the population. We find that this method alters the key relationship between cell size and the amount of protein accumulated for flagellar growth. This provides a rapid alternative to traditional methods of cell synchronization for uncovering novel regulators of cilia. PMID:28289724

Flagellar Synchronization Is a Simple Alternative to Cell Cycle Synchronization for Ciliary and Flagellar Studies.

PubMed

Dutta, Soumita; Avasthi, Prachee

2017-01-01

The unicellular green alga Chlamydomonas reinhardtii is an ideal model organism for studies of ciliary function and assembly. In assays for biological and biochemical effects of various factors on flagellar structure and function, synchronous culture is advantageous for minimizing variability. Here, we have characterized a method in which 100% synchronization is achieved with respect to flagellar length but not with respect to the cell cycle. The method requires inducing flagellar regeneration by amputation of the entire cell population and limiting regeneration time. This results in a maximally homogeneous distribution of flagellar lengths at 3 h postamputation. We found that time-limiting new protein synthesis during flagellar synchronization limits variability in the unassembled pool of limiting flagellar protein and variability in flagellar length without affecting the range of cell volumes. We also found that long- and short-flagella mutants that regenerate normally require longer and shorter synchronization times, respectively. By minimizing flagellar length variability using a simple method requiring only hours and no changes in media, flagellar synchronization facilitates the detection of small changes in flagellar length resulting from both chemical and genetic perturbations in Chlamydomonas . This method increases our ability to probe the basic biology of ciliary size regulation and related disease etiologies. IMPORTANCE Cilia and flagella are highly conserved antenna-like organelles that found in nearly all mammalian cell types. They perform sensory and motile functions contributing to numerous physiological and developmental processes. Defects in their assembly and function are implicated in a wide range of human diseases ranging from retinal degeneration to cancer. Chlamydomonas reinhardtii is an algal model system for studying mammalian cilium formation and function. Here, we report a simple synchronization method that allows detection of small changes in ciliary length by minimizing variability in the population. We find that this method alters the key relationship between cell size and the amount of protein accumulated for flagellar growth. This provides a rapid alternative to traditional methods of cell synchronization for uncovering novel regulators of cilia.

Pinning synchronization of memristor-based neural networks with time-varying delays.

PubMed

Yang, Zhanyu; Luo, Biao; Liu, Derong; Li, Yueheng

2017-09-01

In this paper, the synchronization of memristor-based neural networks with time-varying delays via pinning control is investigated. A novel pinning method is introduced to synchronize two memristor-based neural networks which denote drive system and response system, respectively. The dynamics are studied by theories of differential inclusions and nonsmooth analysis. In addition, some sufficient conditions are derived to guarantee asymptotic synchronization and exponential synchronization of memristor-based neural networks via the presented pinning control. Furthermore, some improvements about the proposed control method are also discussed in this paper. Finally, the effectiveness of the obtained results is demonstrated by numerical simulations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mapping the Information Trace in Local Field Potentials by a Computational Method of Two-Dimensional Time-Shifting Synchronization Likelihood Based on Graphic Processing Unit Acceleration.

PubMed

Zhao, Zi-Fang; Li, Xue-Zhu; Wan, You

2017-12-01

The local field potential (LFP) is a signal reflecting the electrical activity of neurons surrounding the electrode tip. Synchronization between LFP signals provides important details about how neural networks are organized. Synchronization between two distant brain regions is hard to detect using linear synchronization algorithms like correlation and coherence. Synchronization likelihood (SL) is a non-linear synchronization-detecting algorithm widely used in studies of neural signals from two distant brain areas. One drawback of non-linear algorithms is the heavy computational burden. In the present study, we proposed a graphic processing unit (GPU)-accelerated implementation of an SL algorithm with optional 2-dimensional time-shifting. We tested the algorithm with both artificial data and raw LFP data. The results showed that this method revealed detailed information from original data with the synchronization values of two temporal axes, delay time and onset time, and thus can be used to reconstruct the temporal structure of a neural network. Our results suggest that this GPU-accelerated method can be extended to other algorithms for processing time-series signals (like EEG and fMRI) using similar recording techniques.

Cell Cycle Synchronization of HeLa Cells to Assay EGFR Pathway Activation.

PubMed

Wee, Ping; Wang, Zhixiang

2017-01-01

Progression through the cell cycle causes changes in the cell's signaling pathways that can alter EGFR signal transduction. Here, we describe drug-derived protocols to synchronize HeLa cells in various phases of the cell cycle, including G1 phase, S phase, G2 phase, and mitosis, specifically in the mitotic stages of prometaphase, metaphase, and anaphase/telophase. The synchronization procedures are designed to allow synchronized cells to be treated for EGF and collected for the purpose of Western blotting for EGFR signal transduction components.S phase synchronization is performed by thymidine block, G2 phase with roscovitine, prometaphase with nocodazole, metaphase with MG132, and anaphase/telophase with blebbistatin. G1 phase synchronization is performed by culturing synchronized mitotic cells obtained by mitotic shake-off. We also provide methods to validate the synchronization methods. For validation by Western blotting, we provide the temporal expression of various cell cycle markers that are used to check the quality of the synchronization. For validation of mitotic synchronization by microscopy, we provide a guide that describes the physical properties of each mitotic stage, using their cellular morphology and DNA appearance. For validation by flow cytometry, we describe the use of imaging flow cytometry to distinguish between the phases of the cell cycle, including between each stage of mitosis.

Distributed synchronization of networked drive-response systems: A nonlinear fixed-time protocol.

PubMed

Zhao, Wen; Liu, Gang; Ma, Xi; He, Bing; Dong, Yunfeng

2017-11-01

The distributed synchronization of networked drive-response systems is investigated in this paper. A novel nonlinear protocol is proposed to ensure that the tracking errors converge to zeros in a fixed-time. By comparison with previous synchronization methods, the present method considers more practical conditions and the synchronization time is not dependent of arbitrary initial conditions but can be offline pre-assign according to the task assignment. Finally, the feasibility and validity of the presented protocol have been illustrated by a numerical simulation. Copyright © 2017. Published by Elsevier Ltd.

Ovulation Statuses of Surrogate Gilts Are Associated with the Efficiency of Excellent Pig Cloning.

PubMed

Huan, Yanjun; Hu, Kui; Xie, Bingteng; Shi, Yongqian; Wang, Feng; Zhou, Yang; Liu, Shichao; Huang, Bo; Zhu, Jiang; Liu, Zhongfeng; He, Yilong; Li, Jingyu; Kong, Qingran; Liu, Zhonghua

2015-01-01

Somatic cell nuclear transfer (SCNT) is an assisted reproductive technique that can produce multiple copies of excellent livestock. However, low cloning efficiency limits the application of SCNT. In this study, we systematically investigated the major influencing factors related to the overall cloning efficiency in pigs. Here, 13620 cloned embryos derived from excellent pigs were transferred into 79 surrogate gilts, and 119 live cloned piglets were eventually generated. During cloning, group of cloned embryos derived from excellent Landrace or Large white pigs presented no significant differences of cleavage and blastocyst rates, blastocyst cell numbers, surrogate pregnancy and delivery rates, average numbers of piglets born and alive and cloning efficiencies, and group of 101-150, 151-200 or 201-250 cloned embryos transferred per surrogate also displayed a similar developmental efficiency. When estrus stage of surrogate gilts was compared, group of embryo transfer on Day 2 of estrus showed significantly higher pregnancy rate, delivery rate, average number of piglets born, average alive piglet number or cloning efficiency than group on Day 1, Day 3, Day 4 or Day 5, respectively (P<0.05). And, in comparison with the preovulation and postovulation groups, group of surrogate gilts during periovulation displayed a significantly higher overall cloning efficiency (P<0.05). Further investigation of surrogate estrus stage and ovulation status displayed that ovulation status was the real factor underlying estrus stage to determine the overall cloning efficiency. And more, follicle puncture for preovulation, not transfer position shallowed for preovulation or deepened for postovulation, significantly improved the average number of piglets alive and cloning efficiency (P<0.05). In conclusion, our results demonstrated that ovulation status of surrogate gilts was the fundamental factor determining the overall cloning efficiency of excellent pigs, and follicle puncture, not transfer position change, improved cloning efficiency. This work would have important implications in preserving and breeding excellent livestock and improving the overall cloning efficiency.

Ovulation Statuses of Surrogate Gilts Are Associated with the Efficiency of Excellent Pig Cloning

PubMed Central

Huan, Yanjun; Hu, Kui; Xie, Bingteng; Shi, Yongqian; Wang, Feng; Zhou, Yang; Liu, Shichao; Huang, Bo; Zhu, Jiang; Liu, Zhongfeng; He, Yilong; Li, Jingyu; Kong, Qingran; Liu, Zhonghua

2015-01-01

Somatic cell nuclear transfer (SCNT) is an assisted reproductive technique that can produce multiple copies of excellent livestock. However, low cloning efficiency limits the application of SCNT. In this study, we systematically investigated the major influencing factors related to the overall cloning efficiency in pigs. Here, 13620 cloned embryos derived from excellent pigs were transferred into 79 surrogate gilts, and 119 live cloned piglets were eventually generated. During cloning, group of cloned embryos derived from excellent Landrace or Large white pigs presented no significant differences of cleavage and blastocyst rates, blastocyst cell numbers, surrogate pregnancy and delivery rates, average numbers of piglets born and alive and cloning efficiencies, and group of 101–150, 151–200 or 201–250 cloned embryos transferred per surrogate also displayed a similar developmental efficiency. When estrus stage of surrogate gilts was compared, group of embryo transfer on Day 2 of estrus showed significantly higher pregnancy rate, delivery rate, average number of piglets born, average alive piglet number or cloning efficiency than group on Day 1, Day 3, Day 4 or Day 5, respectively (P<0.05). And, in comparison with the preovulation and postovulation groups, group of surrogate gilts during periovulation displayed a significantly higher overall cloning efficiency (P<0.05). Further investigation of surrogate estrus stage and ovulation status displayed that ovulation status was the real factor underlying estrus stage to determine the overall cloning efficiency. And more, follicle puncture for preovulation, not transfer position shallowed for preovulation or deepened for postovulation, significantly improved the average number of piglets alive and cloning efficiency (P<0.05). In conclusion, our results demonstrated that ovulation status of surrogate gilts was the fundamental factor determining the overall cloning efficiency of excellent pigs, and follicle puncture, not transfer position change, improved cloning efficiency. This work would have important implications in preserving and breeding excellent livestock and improving the overall cloning efficiency. PMID:26565717

Exposure to Photoperiod-Melatonin-Induced, Sexually-Activated Rams after Weaning Advances the Resumption of Sexual Activity in Post-Partum Mediterranean Ewes Lambing in January.

PubMed

Abecia, José A; Chemineau, Philippe; Gómez, Andrea; Palacios, Carlos; Keller, Matthieu; Delgadillo, José A

2017-01-21

This study was aimed to determine whether the presence of sexually stimulated rams by photoperiodic and melatonin treatments can advance the resumption of post-partum sexual activity in Mediterranean ewes lambing in January and weaned at the end of the breeding season at 41°N, in March. Rams were exposed to two months of long days (16 h light/day) and given three melatonin implants at the end of the long days (sexually-activated rams; SAR). Control rams (CR) were exposed to the natural photoperiod. Thirty-six ewes weaned on 25 February were assigned to one of two groups. From 1 March to 30 June, one group was housed with four SAR males (SAR-treated; n = 18), and the other group (CR-treated; n = 18) was housed with four unstimulated rams. Ovulation was assessed once per week based on plasma progesterone concentrations. Estrus was monitored daily by marks left on ewes by rams' harnesses. SAR-treated ewes had a shorter ( p < 0.01) weaning-first estrus interval than CR-treated ewes (61 ± 17 days vs. 102 ± 47 days; mean date of first estrus after weaning on April 26 and June 6, respectively). The proportion of the ewes ovulating in April or May was higher ( p < 0.05) in the SAR-treated group than in the CR-treated group. SAR-treated ewes resumed estrous activity sooner than CR-treated ewes such that, in April, May, and June, the proportion of females that exhibited estrus was higher ( p < 0.01) in the SAR-treated group (72%, 89%, and 100%, respectively) than in the CR-treated group (17%, 44%, and 61%, respectively). In conclusion, the introduction at weaning of sexually activated rams advanced the resumption of estrous activity in ewes in spring. The practical implications of this work could be important in ewes adapted for intensive production and accelerated lambing systems.

Exposure to Photoperiod-Melatonin-Induced, Sexually-Activated Rams after Weaning Advances the Resumption of Sexual Activity in Post-Partum Mediterranean Ewes Lambing in January

PubMed Central

Abecia, José A.; Chemineau, Philippe; Gómez, Andrea; Palacios, Carlos; Keller, Matthieu; Delgadillo, José A.

2017-01-01

This study was aimed to determine whether the presence of sexually stimulated rams by photoperiodic and melatonin treatments can advance the resumption of post-partum sexual activity in Mediterranean ewes lambing in January and weaned at the end of the breeding season at 41°N, in March. Rams were exposed to two months of long days (16 h light/day) and given three melatonin implants at the end of the long days (sexually-activated rams; SAR). Control rams (CR) were exposed to the natural photoperiod. Thirty-six ewes weaned on 25 February were assigned to one of two groups. From 1 March to 30 June, one group was housed with four SAR males (SAR-treated; n = 18), and the other group (CR-treated; n = 18) was housed with four unstimulated rams. Ovulation was assessed once per week based on plasma progesterone concentrations. Estrus was monitored daily by marks left on ewes by rams’ harnesses. SAR-treated ewes had a shorter (p < 0.01) weaning–first estrus interval than CR-treated ewes (61 ± 17 days vs. 102 ± 47 days; mean date of first estrus after weaning on April 26 and June 6, respectively). The proportion of the ewes ovulating in April or May was higher (p < 0.05) in the SAR-treated group than in the CR-treated group. SAR-treated ewes resumed estrous activity sooner than CR-treated ewes such that, in April, May, and June, the proportion of females that exhibited estrus was higher (p < 0.01) in the SAR-treated group (72%, 89%, and 100%, respectively) than in the CR-treated group (17%, 44%, and 61%, respectively). In conclusion, the introduction at weaning of sexually activated rams advanced the resumption of estrous activity in ewes in spring. The practical implications of this work could be important in ewes adapted for intensive production and accelerated lambing systems. PMID:29056663

Appetitive and Consummatory Sexual Behaviors of Rams Treated with Exogenous Testosterone and Exposed to Anestrus Dorper Ewes: Efficacy of the Male Effect.

PubMed

Tejada, Luz M; Meza-Herrera, Cesar A; Rivas-Muñoz, Raymundo; Rodríguez-Martínez, Rafael; Carrillo, Evaristo; Mellado, Miguel; Véliz-Deras, Francisco G

2017-04-01

We determine whether Dorper rams treated with testosterone in the sexual resting season trigger both appetitive and consummatory sexual behaviors and sexual and reproductive outcomes in anestrous ewes at 26° North during March-April. Dorper rams (n = 12, 2.5 years) were randomly divided prior to mating in two groups: GT (treated group; n = 6), treated with testosterone propionate (25 mg i.m. every 3 days × 3 weeks) and GC (control group; n = 6), treated with saline. Thereafter, adult anovulatory Dorper ewes (n = 61) were exposed to the GT-rams while the other group (n = 60) was exposed to the GC-rams. Ram's appetitive sexual behavior was similar (50 %) in both groups, yet the GT-rams exerted 100 % of the consummatory sexual behavior. Sexual and reproductive outcomes of the anestrus females exposed to both male groups considered two phases: 0-15 and 16-25 days from exposure to males. Involved variables were: ewes in estrus, ewes ovulating, duration of estrus, pregnant ewes, and lambed ewes. All the average variables favored those ewes exposed to GT-males: ewes in estrus: 85 versus 40 %; ewes ovulating: 80 versus 53 %; duration of estrus: 37 versus 25 h; pregnant ewes: 60 versus 31 %, and lambed ewes: 57 versus 31 %. Results confirm that adult Dorper rams treated with exogenous testosterone had improved consummatory sexual behavior and induced increased ovulation and pregnancy rates when exposed to anestrus ewes. This feasible and inexpensive testosterone-based protocol through the male effect also enhanced both sexual and reproductive outcomes in previously anestrous Dorper ewes during the natural out-of-season. Results are important to speed up reproductive performance of sheep during the natural anestrous season at this latitude, while also they embrace interesting outcomes from a comparative sexual behavior stand point.

General hybrid projective complete dislocated synchronization with non-derivative and derivative coupling based on parameter identification in several chaotic and hyperchaotic systems

NASA Astrophysics Data System (ADS)

Sun, Jun-Wei; Shen, Yi; Zhang, Guo-Dong; Wang, Yan-Feng; Cui, Guang-Zhao

2013-04-01

According to the Lyapunov stability theorem, a new general hybrid projective complete dislocated synchronization scheme with non-derivative and derivative coupling based on parameter identification is proposed under the framework of drive-response systems. Every state variable of the response system equals the summation of the hybrid drive systems in the previous hybrid synchronization. However, every state variable of the drive system equals the summation of the hybrid response systems while evolving with time in our method. Complete synchronization, hybrid dislocated synchronization, projective synchronization, non-derivative and derivative coupling, and parameter identification are included as its special item. The Lorenz chaotic system, Rössler chaotic system, memristor chaotic oscillator system, and hyperchaotic Lü system are discussed to show the effectiveness of the proposed methods.

Magnesium Object Manager Sandbox, A More Effective Sandbox Method for Windows 7

DTIC Science & Technology

2012-03-01

keys, synchronization primitives , etc.). The object body is specific to, and the same for, each object type; it contains information common to each...the Object Directory Specific Rights Synchronization Object (Event, Mutex, Semaphore , Timer) Synchronization objects allow multiple threads to... Synchronization Object Specific Rights . . . . . . . . . . . . . . . . . . . . . 19 2.5 File Object Specific Rights

Partial and Synchronized Captioning: A New Tool for Second Language Listening Development

ERIC Educational Resources Information Center

Mirzaei, Maryam Sadat; Akita, Yuya; Kawahara, Tatsuya

2014-01-01

This study investigates a novel method of captioning, partial and synchronized, as a listening tool for second language (L2) learners. In this method, the term partial and synchronized caption (PSC) pertains to the presence of a selected set of words in a caption where words are synced to their corresponding speech signal, using a state-of-the-art…

Retention payoff-based cost per day open regression equations: Application in a user-friendly decision support tool for investment analysis of automated estrus detection technologies.

PubMed

Dolecheck, K A; Heersche, G; Bewley, J M

2016-12-01

Assessing the economic implications of investing in automated estrus detection (AED) technologies can be overwhelming for dairy producers. The objectives of this study were to develop new regression equations for estimating the cost per day open (DO) and to apply the results to create a user-friendly, partial budget, decision support tool for investment analysis of AED technologies. In the resulting decision support tool, the end user can adjust herd-specific inputs regarding general management, current reproductive management strategies, and the proposed AED system. Outputs include expected DO, reproductive cull rate, net present value, and payback period for the proposed AED system. Utility of the decision support tool was demonstrated with an example dairy herd created using data from DairyMetrics (Dairy Records Management Systems, Raleigh, NC), Food and Agricultural Policy Research Institute (Columbia, MO), and published literature. Resulting herd size, rolling herd average milk production, milk price, and feed cost were 323 cows, 10,758kg, $0.41/kg, and $0.20/kg of dry matter, respectively. Automated estrus detection technologies with 2 levels of initial system cost (low: $5,000 vs. high: $10,000), tag price (low: $50 vs. high: $100), and estrus detection rate (low: 60% vs. high: 80%) were compared over a 7-yr investment period. Four scenarios were considered in a demonstration of the investment analysis tool: (1) a herd using 100% visual observation for estrus detection before adopting 100% AED, (2) a herd using 100% visual observation before adopting 75% AED and 25% visual observation, (3) a herd using 100% timed artificial insemination (TAI) before adopting 100% AED, and (4) a herd using 100% TAI before adopting 75% AED and 25% TAI. Net present value in scenarios 1 and 2 was always positive, indicating a positive investment situation. Net present value in scenarios 3 and 4 was always positive in combinations using a $50 tag price, and in scenario 4, the $5,000, $100, and 80% combination. Overall, the payback period ranged from 1.6 yr to greater than 10 yr. Investment analysis demonstration results were highly dependent on assumptions, especially AED system initial investment and labor costs. Dairy producers can use herd-specific inputs with the cost per day open regression equations and the decision support tool to estimate individual herd results. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Determining the degree of synchronism for intermittent phase synchronization in human electroencephalography data

NASA Astrophysics Data System (ADS)

Koloskova, A. D.; Moskalenko, O. I.

2017-05-01

The phenomenon of intermittent phase synchronization during development of epileptic activity in human beings has been discovered based on EEG data. The presence of synchronous behavior phases has been detected both during spike-wave discharges and in the regions of background activity of the brain. The degree of synchronism in the intermittent phase-synchronization regime in both cases has been determined, and it has been established that spike-wave discharges are characterized by a higher degree of synchronism than exists in the regions of background activity of the brain. To determine the degree of synchronism, a modified method of evaluating zero conditional Lyapunov exponents from time series is proposed.

Transponder-aided joint calibration and synchronization compensation for distributed radar systems.

PubMed

Wang, Wen-Qin

2015-01-01

High-precision radiometric calibration and synchronization compensation must be provided for distributed radar system due to separate transmitters and receivers. This paper proposes a transponder-aided joint radiometric calibration, motion compensation and synchronization for distributed radar remote sensing. As the transponder signal can be separated from the normal radar returns, it is used to calibrate the distributed radar for radiometry. Meanwhile, the distributed radar motion compensation and synchronization compensation algorithms are presented by utilizing the transponder signals. This method requires no hardware modifications to both the normal radar transmitter and receiver and no change to the operating pulse repetition frequency (PRF). The distributed radar radiometric calibration and synchronization compensation require only one transponder, but the motion compensation requires six transponders because there are six independent variables in the distributed radar geometry. Furthermore, a maximum likelihood method is used to estimate the transponder signal parameters. The proposed methods are verified by simulation results.

Local synchronization of a complex network model.

PubMed

Yu, Wenwu; Cao, Jinde; Chen, Guanrong; Lü, Jinhu; Han, Jian; Wei, Wei

2009-02-01

This paper introduces a novel complex network model to evaluate the reputation of virtual organizations. By using the Lyapunov function and linear matrix inequality approaches, the local synchronization of the proposed model is further investigated. Here, the local synchronization is defined by the inner synchronization within a group which does not mean the synchronization between different groups. Moreover, several sufficient conditions are derived to ensure the local synchronization of the proposed network model. Finally, several representative examples are given to show the effectiveness of the proposed methods and theories.

Finite-time master-slave synchronization and parameter identification for uncertain Lurie systems.

PubMed

Wang, Tianbo; Zhao, Shouwei; Zhou, Wuneng; Yu, Weiqin

2014-07-01

This paper investigates the finite-time master-slave synchronization and parameter identification problem for uncertain Lurie systems based on the finite-time stability theory and the adaptive control method. The finite-time master-slave synchronization means that the state of a slave system follows with that of a master system in finite time, which is more reasonable than the asymptotical synchronization in applications. The uncertainties include the unknown parameters and noise disturbances. An adaptive controller and update laws which ensures the synchronization and parameter identification to be realized in finite time are constructed. Finally, two numerical examples are given to show the effectiveness of the proposed method. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

A new scheme of general hybrid projective complete dislocated synchronization

NASA Astrophysics Data System (ADS)

Chu, Yan-dong; Chang, Ying-Xiang; An, Xin-lei; Yu, Jian-Ning; Zhang, Jian-Gang

2011-03-01

Based on the Lyapunov stability theorem, a new type of chaos synchronization, general hybrid projective complete dislocated synchronization (GHPCDS), is proposed under the framework of drive-response systems. The difference between the GHPCDS and complete synchronization is that every state variable of drive system does not equal the corresponding state variable, but equal other ones of response system while evolving in time. The GHPCDS includes complete dislocated synchronization, dislocated anti-synchronization and projective dislocated synchronization as its special item. As examples, the Lorenz chaotic system, Rössler chaotic system, hyperchaotic Chen system and hyperchaotic Lü system are discussed. Numerical simulations are given to show the effectiveness of these methods.

LQR-Based Optimal Distributed Cooperative Design for Linear Discrete-Time Multiagent Systems.

PubMed

Zhang, Huaguang; Feng, Tao; Liang, Hongjing; Luo, Yanhong

2017-03-01

In this paper, a novel linear quadratic regulator (LQR)-based optimal distributed cooperative design method is developed for synchronization control of general linear discrete-time multiagent systems on a fixed, directed graph. Sufficient conditions are derived for synchronization, which restrict the graph eigenvalues into a bounded circular region in the complex plane. The synchronizing speed issue is also considered, and it turns out that the synchronizing region reduces as the synchronizing speed becomes faster. To obtain more desirable synchronizing capacity, the weighting matrices are selected by sufficiently utilizing the guaranteed gain margin of the optimal regulators. Based on the developed LQR-based cooperative design framework, an approximate dynamic programming technique is successfully introduced to overcome the (partially or completely) model-free cooperative design for linear multiagent systems. Finally, two numerical examples are given to illustrate the effectiveness of the proposed design methods.

Synchronization of Switched Neural Networks With Communication Delays via the Event-Triggered Control.

PubMed

Wen, Shiping; Zeng, Zhigang; Chen, Michael Z Q; Huang, Tingwen

2017-10-01

This paper addresses the issue of synchronization of switched delayed neural networks with communication delays via event-triggered control. For synchronizing coupled switched neural networks, we propose a novel event-triggered control law which could greatly reduce the number of control updates for synchronization tasks of coupled switched neural networks involving embedded microprocessors with limited on-board resources. The control signals are driven by properly defined events, which depend on the measurement errors and current-sampled states. By using a delay system method, a novel model of synchronization error system with delays is proposed with the communication delays and event-triggered control in the unified framework for coupled switched neural networks. The criteria are derived for the event-triggered synchronization analysis and control synthesis of switched neural networks via the Lyapunov-Krasovskii functional method and free weighting matrix approach. A numerical example is elaborated on to illustrate the effectiveness of the derived results.

Synchronization of Somatic Embryogenesis in Date Palm Suspension Culture Using Abscisic Acid.

PubMed

Alwael, Hussain A; Naik, Poornananda M; Al-Khayri, Jameel M

2017-01-01

Somatic embryogenesis is considered the most effective method for commercial propagation of date palm. However, the limitation of obtaining synchronized development of somatic embryos remains an impediment. The synchronization of somatic embryo development is ideal for the applications to produce artificial seeds. Abscisic acid (ABA) is associated with stress response and influences in vitro growth and development. This chapter describes an effective method to achieve synchronized development of somatic embryos in date palm cell suspension culture. Among the ABA concentrations tested (0, 1, 10, 50, 100 μM), the best synchronized growth was obtained in response to 50-100 μM. Here we provide a comprehensive protocol for in vitro plant regeneration of date palm starting with shoot-tip explant, callus initiation and growth, cell suspension establishment, embryogenesis synchronization with ABA treatment, somatic embryo germination, and rooting as well as acclimatized plantlet establishment.

Using UHF proximity loggers to quantify male-female interactions: a scoping study of estrous activity in cattle.

PubMed

O'Neill, C J; Bishop-Hurley, G J; Williams, P J; Reid, D J; Swain, D L

2014-12-10

Reproductive efficiency is an important determinant of profitable cattle breeding systems and the success of assisted reproductive techniques (ART) in wildlife conservation programs. Methods of estrous detection used in intensive beef and dairy cattle systems lack accuracy and remain the single biggest issue for improvement of reproductive rates and such methods are not practical for either large-scale extensive beef cattle enterprises or free-living mammalian species. Recent developments in UHF (ultra high frequency) proximity logger telemetry devices have been used to provide a continuous pair-wise measure of associations between individual animals for both livestock and wildlife. The objective of this study was to explore the potential of using UHF telemetry to identify the reproductive cycle phenotype in terms of intensity and duration of estrus. The study was conducted using Belmont Red (interbred Africander Brahman Hereford-Shorthorn) cattle grazing irrigated pasture on Belmont Research Station, northeastern Australia. The cow-bull associations from three groups of cows each with one bull were recorded over a 7-week breeding season and the stage of estrus was identified using ultrasonography. Telemetry data from bull and cows, collected over 4 8-day logger deployments, were log transformed and analyzed by ANOVA. Both the number and duration of bull-cow affiliations were significantly (P<0.001) greater in estrous cows compared to anestrus cows. These results support the development of the UHF technology as a hands-off and noninvasive means of gathering socio-sexual information on both wildlife and livestock for reproductive management. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

Solving Integer Programs from Dependence and Synchronization Problems

DTIC Science & Technology

1993-03-01

DEFF.NSNE Solving Integer Programs from Dependence and Synchronization Problems Jaspal Subhlok March 1993 CMU-CS-93-130 School of Computer ScienceT IC...method Is an exact and efficient way of solving integer programming problems arising in dependence and synchronization analysis of parallel programs...7/;- p Keywords: Exact dependence tesing, integer programming. parallelilzng compilers, parallel program analysis, synchronization analysis Solving

A precise time synchronization method for 5G based on radio-over-fiber network with SDN controller

NASA Astrophysics Data System (ADS)

He, Linkuan; Wei, Baoguo; Yang, Hui; Yu, Ao; Wang, Zhengyong; Zhang, Jie

2018-02-01

There is an increasing demand on accurate time synchronization with the growing bandwidth of network service for 5G. In 5G network, it's necessary for base station to achieve accurate time synchronization to guarantee the quality of communication. In order to keep accuracy time for 5G network, we propose a time synchronization system for satellite ground station based on radio-over-fiber network (RoFN) with software defined optical network (SDON) controller. The advantage of this method is to improve the accuracy of time synchronization of ground station. The IEEE 1588 time synchronization protocol can solve the problems of high cost and lack of precision. However, in the process of time synchronization, distortion exists during the transmission of digital time signal. RoF uses analog optical transmission links and therefore analog transmission can be implemented among ground stations instead of digital transmission, which means distortion and bandwidth waste in the process of digital synchronization can be avoided. Additionally, the thought of SDN, software defined network, can optimize RoFN with centralized control and simplifying base station. Related simulation had been carried out to prove its superiority.

Asynchronous Video Streaming vs. Synchronous Videoconferencing for Teaching a Pharmacogenetic Pharmacotherapy Course

PubMed Central

2007-01-01

Objectives To compare students' performance and course evaluations for a pharmacogenetic pharmacotherapy course taught by synchronous videoconferencing method via the Internet and for the same course taught via asynchronous video streaming via the Internet. Methods In spring 2005, a pharmacogenetic therapy course was taught to 73 students located on Amarillo, Lubbock, and Dallas campuses using synchronous videoconferencing, and in spring 2006, to 78 students located on the same 3 campuses using asynchronous video streaming. A course evaluation was administered to each group at the end of the courses. Results Students in the asynchronous setting had final course grades of 89% ± 7% compared to the mean final course grade of 87% ± 7% in the synchronous group (p = 0.05). Regardless of which technology was used, average course grades did not differ significantly among the 3 campus sites. Significantly more of the students in the asynchronous setting agreed (57%) with the statement that they could read the lecture notes and absorb the content on their own without attending the class than students in the synchronous class (23%; chi-square test; p < 0.001). Conclusions Students in both asynchronous and synchronous settings performed well. However, students taught using asynchronous videotaped lectures had lower satisfaction with the method of content delivery, and preferred live interactive sessions or a mix of interactive sessions and asynchronous videos over delivery of content using the synchronous or asynchronous method alone. PMID:17429516

Pilotless Frame Synchronization Using LDPC Code Constraints

NASA Technical Reports Server (NTRS)

Jones, Christopher; Vissasenor, John

2009-01-01

A method of pilotless frame synchronization has been devised for low- density parity-check (LDPC) codes. In pilotless frame synchronization , there are no pilot symbols; instead, the offset is estimated by ex ploiting selected aspects of the structure of the code. The advantag e of pilotless frame synchronization is that the bandwidth of the sig nal is reduced by an amount associated with elimination of the pilot symbols. The disadvantage is an increase in the amount of receiver data processing needed for frame synchronization.

Synchronization of two homodromy rotors installed on a double vibro-body in a coupling vibration system.

PubMed

Fang, Pan; Hou, Yongjun; Nan, Yanghai

2015-01-01

A new mechanism is proposed to implement synchronization of the two unbalanced rotors in a vibration system, which consists of a double vibro-body, two induction motors and spring foundations. The coupling relationship between the vibro-bodies is ascertained with the Laplace transformation method for the dynamics equation of the system obtained with the Lagrange's equation. An analytical approach, the average method of modified small parameters, is employed to study the synchronization characteristics between the two unbalanced rotors, which is converted into that of existence and the stability of zero solutions for the non-dimensional differential equations of the angular velocity disturbance parameters. By assuming the disturbance parameters that infinitely approach to zero, the synchronization condition for the two rotors is obtained. It indicated that the absolute value of the residual torque between the two motors should be equal to or less than the maximum of their coupling torques. Meanwhile, the stability criterion of synchronization is derived with the Routh-Hurwitz method, and the region of the stable phase difference is confirmed. At last, computer simulations are preformed to verify the correctness of the approximate solution of the theoretical computation for the stable phase difference between the two unbalanced rotors, and the results of theoretical computation is in accordance with that of computer simulations. To sum up, only the parameters of the vibration system satisfy the synchronization condition and the stability criterion of the synchronization, the two unbalanced rotors can implement the synchronization operation.

Synchronization of Two Homodromy Rotors Installed on a Double Vibro-Body in a Coupling Vibration System

PubMed Central

Fang, Pan; Hou, Yongjun; Nan, Yanghai

2015-01-01

A new mechanism is proposed to implement synchronization of the two unbalanced rotors in a vibration system, which consists of a double vibro-body, two induction motors and spring foundations. The coupling relationship between the vibro-bodies is ascertained with the Laplace transformation method for the dynamics equation of the system obtained with the Lagrange’s equation. An analytical approach, the average method of modified small parameters, is employed to study the synchronization characteristics between the two unbalanced rotors, which is converted into that of existence and the stability of zero solutions for the non-dimensional differential equations of the angular velocity disturbance parameters. By assuming the disturbance parameters that infinitely approach to zero, the synchronization condition for the two rotors is obtained. It indicated that the absolute value of the residual torque between the two motors should be equal to or less than the maximum of their coupling torques. Meanwhile, the stability criterion of synchronization is derived with the Routh-Hurwitz method, and the region of the stable phase difference is confirmed. At last, computer simulations are preformed to verify the correctness of the approximate solution of the theoretical computation for the stable phase difference between the two unbalanced rotors, and the results of theoretical computation is in accordance with that of computer simulations. To sum up, only the parameters of the vibration system satisfy the synchronization condition and the stability criterion of the synchronization, the two unbalanced rotors can implement the synchronization operation. PMID:25993472

Removal of anti-Stokes emission background in STED microscopy by FPGA-based synchronous detection

NASA Astrophysics Data System (ADS)

Castello, M.; Tortarolo, G.; Coto Hernández, I.; Deguchi, T.; Diaspro, A.; Vicidomini, G.

2017-05-01

In stimulated emission depletion (STED) microscopy, the role of the STED beam is to de-excite, via stimulated emission, the fluorophores that have been previously excited by the excitation beam. This condition, together with specific beam intensity distributions, allows obtaining true sub-diffraction spatial resolution images. However, if the STED beam has a non-negligible probability to excite the fluorophores, a strong fluorescent background signal (anti-Stokes emission) reduces the effective resolution. For STED scanning microscopy, different synchronous detection methods have been proposed to remove this anti-Stokes emission background and recover the resolution. However, every method works only for a specific STED microscopy implementation. Here we present a user-friendly synchronous detection method compatible with any STED scanning microscope. It exploits a data acquisition (DAQ) card based on a field-programmable gate array (FPGA), which is progressively used in STED microscopy. In essence, the FPGA-based DAQ card synchronizes the fluorescent signal registration, the beam deflection, and the excitation beam interruption, providing a fully automatic pixel-by-pixel synchronous detection method. We validate the proposed method in both continuous wave and pulsed STED microscope systems.

Innovative Methods for Providing Instruction to Distance Students Using Technology.

ERIC Educational Resources Information Center

Pival, Paul R.; Tunon, Johanna

2001-01-01

Examines three innovative methods tried at Nova Southeastern University for providing quality bibliographic instruction to distance students: one synchronous, one asynchronous, and one that combined features from both synchronous and asynchronous methods of delivering instruction. Topics include compressed video, collaborative groupware, streaming…

Characterization and manipulation of reproductive cycles in the jaguar (Panthera onca).

PubMed

Barnes, Serena A; Andrew Teare, J; Staaden, Sheryl; Metrione, Lara; Penfold, Linda M

2016-01-01

Basic reproductive information in female jaguars (Panthera onca) is lacking, thus longitudinal fecal samples from seven females were analyzed via enzyme immunoassay to measure estradiol and progestin metabolites throughout the year. Mean estrus length of 194 estrus periods measured hormonally was 6.5±0.3d, mean peak fecal estradiol concentration was 138.7±5.7ng/g; and in one female, estrus resumption occurred approximately 15d post-partum. Ovulation, as indicted by sustained elevated progestin concentrations (>20d), was successfully induced one time by treatment with exogenous hormones in one female and by physical vaginal stimulation in two females a combined total of three times. Elevated fecal progestin was observed outside exogenous stimulation on five occasions, suggesting ovulation occurred spontaneously. Mean length of physically induced and spontaneous pseudopregnancies was 24.7±4.2d and 29.6±2.6d, respectively, and mean length of pregnancy (n=2) was 98.0±0.0d. Mean peak progestin concentration for spontaneous and induced pseudopregnancies, and pregnancy was 7.4±1.4μg/g, 6.4±1.2μg/g, and 13.7±1.0μg/g, respectively. This data suggests jaguars are polyestrous and generally induced ovulators, with a moderate incidence of spontaneous ovulation. Additionally, two protocols to successfully stimulate ovarian activity in jaguars are described. Copyright © 2015 Elsevier Inc. All rights reserved.

LPS-Challenged TNFα Production, Prostaglandin Secretion, and TNFα/TNFRs Expression in the Endometrium of Domestic Cats in Estrus or Diestrus, and in Cats with Pyometra or Receiving Medroxyprogesterone Acetate

PubMed Central

Jursza, Ewelina; Szóstek, Anna Z.; Kowalewski, Mariusz P.; Boos, Alois; Okuda, Kiyoshi; Siemieniuch, Marta J.

2014-01-01

Progesterone (P4) derivatives which are commonly used to block the cyclicity of domestic cats disturb the endocrine balance in the endometrium. The aims of this study were (i) to examine whether lipopolysaccharide (LPS) is responsible for enhancement of tumor necrosis factor-α (TNFα) secretion by the feline endometrial epithelial and stromal cells in vitro, (ii) to know whether immunolocalization of TNFα/TNFR1 and TNFR2 differs in cats at estrus or diestrus, receiving medroxyprogesterone acetate and suffering from pyometra, and (iii) to determine if TNFα-challenged prostaglandin secretion is stopped by prostaglandin synthases inhibitors. A total of 37 domestic adult cats in estrus or diestrus, receiving octane medroxyprogesterone or having clinical symptoms of pyometra, were enrolled in this study. The results obtained showed a distinct increase in LPS-challenged TNFα secretion in endometrial epithelial, but not stromal cells. TNFα augmented PG secretion was blocked by phospholipase A2 (PLA2) and cyclooxygeanase-2 (COX-2), but not by mitogen-activated protein kinase (MAPK) inhibitor. TNFα/TNFR1 and 2 protein expressions were limited mostly to the surface and glandular epithelium. TNFα/TNFRs protein was upregulated in the inflammatory uterus and hence may be involved in development of pathologic changes in the endometrial glands in cats receiving exogenous P4 as a hormonal contraceptive. PMID:25028529

Adaptive Plasticity of Vaginal Innervation in Term Pregnant Rats

PubMed Central

Liao, Zhaohui; Smith, Peter G.

2011-01-01

Changes in reproductive status place varied functional demands on the vagina. These include receptivity to male intromission and sperm transport in estrus, barrier functions during early pregnancy, and providing a conduit for fetal passage at parturition. Peripheral innervation regulates vaginal function, which in turn may be influenced by circulating reproductive hormones. We assessed vaginal innervation in diestrus and estrus (before and after the estrous cycle surge in estrogen), and in the early (low estrogen) and late (high estrogen) stages in pregnancy. In vaginal sections from cycling rats, axons immunoreactive for the pan-neuronal marker protein gene product 9.5 (PGP 9.5) showed a small reduction at estrus relative to diestrus, but this difference did not persist after correcting for changes in target size. No changes were detected in axons immunoreactive for tyrosine hydroxylase (sympathetic), vesicular acetylcholine transporter (parasympathetic), or calcitonin gene-related peptide and transient receptor potential vanilloid type 1 (TRPV-1; sensory nociceptors). In rats at 10 days of pregnancy, innervation was similar to that observed in cycling rats. However, at 21 days of pregnancy, axons immunoreactive for PGP 9.5 and each of the subpopulation-selective markers were significantly reduced both when expressed as percentage of sectional area or after correcting for changes in target size. Because peripheral nerves regulate vaginal smooth muscle tone, blood flow, and pain sensitivity, reductions in innervation may represent important adaptive mechanisms facilitating parturition. PMID:21666101

Short term protein supplementation during a long interval prostaglandin-based protocol for timed AI in sheep.

PubMed

Errandonea, N; Fierro, S; Viñoles, C; Gil, J; Banchero, G; Olivera-Muzante, J

2018-03-21

The aim of this study was to evaluate the reproductive impact of a short-term protein supplementation on a long interval prostaglandin-based protocol (two PG injections 15 d apart; PG15) for timed artificial insemination in sheep. During the breeding season, 437 multiparous Merino ewes grazing native pastures (forage allowance of 6 kg of dry matter/100 kg of live weight; crude protein: 10.8%, metabolic energy: 2.1 Mcal/kg of dry matter) were selected. Ewes were allocated, according to body condition score (3.2 ± 0.2) and body weight (40.6 ± 4.9 kg, mean ± SD), to a 2 × 2 factorial design: type of estrus -spontaneous estrus (SE) or induced with PG15 (PG15)-, and supplementation (yes or no) before insemination (+FF; soybean meal at Days -10 to -3; crude protein: 51.9%, metabolic energy: 2.8 Mcal/kg of dry matter; average consumption 0.9% live weight/ewe/day of dry matter). All ewes were cervically artificial inseminated (Day -2 to -3 in SE ewes at estrus detection; Day 0 = timed artificial insemination in PG15 ewes). Ovulation rate on Day 7, non-return to service on Day 23, conception, fertility, prolificacy and fecundity on Day 60 were evaluated. Ovulation rate (1.17 ± 0.40 vs. 1.06 ± 0.25), non-return to service at Day 23 (81.7 vs. 64.2%), conception (78.8 vs. 61.5%), fertility (75.2 vs. 61.5%) and fecundity (0.77 vs. 0.62) were higher in ewes from SE than PG15 group (P < 0.05). However, no differences were observed in prolificacy (1.02 ± 0.16 vs. 1.01 ± 0,12) between groups (P > 0.05). Protein supplementation increased ovulation rate (1.30 ± 0.45 vs. 1.17 ± 0.40), prolificacy (1.18 ± 0.39 vs. 1.02 ± 0.16) and fecundity (0.94 vs. 0.77%; P < 0.05), but not non-return to service on Day 23 (83.8 vs. 81.7%), conception (82.9 vs. 78.8%) or fertility (79.1 vs. 75.2%; P > 0.05) in SE group. The supplement feed to PG15 ewes increased ovulation rate (1.35 ± 0.45 vs. 1.06 ± 0.25), prolificacy (1.25 ± 0.43 vs. 1.01 ± 0.12) and fecundity (0.79 vs. 0.62%; P < 0.05) to levels comparable to SE + FF ewes (P > 0.05). The magnitude of the increase in ovulation rate in PG15 was greater than in the SE group (27 vs. 11%; P < 0.05). However, non-return to service on Day 23 (65.1 vs. 64.2%), conception (63.3 vs 61.5%), and fertility rate (63.3 vs. 61.5%; P < 0.05) remained similar in PG15 supplemented or not supplemented ewes. In conclusion, a short-term protein supplementation before cervical time artificial insemination improved the reproductive performance of ewes synchronized with the PG15 protocol to levels comparable to the SE group. Copyright © 2018 Elsevier Inc. All rights reserved.

21 CFR 529.2464 - Ticarcillin.

Code of Federal Regulations, 2014 CFR

2014-04-01

...) Specifications. Each vial contains ticarcillin disodium powder equivalent to 6 grams of ticarcillin for... 6 grams daily by intrauterine infusion for 3 consecutive days during estrus. (2) Indications for use...

Analysis of Synchronization Phenomena in Broadband Signals with Nonlinear Excitable Media

NASA Astrophysics Data System (ADS)

Chernihovskyi, Anton; Elger, Christian E.; Lehnertz, Klaus

2009-12-01

We apply the method of frequency-selective excitation waves in excitable media to characterize synchronization phenomena in interacting complex dynamical systems by measuring coincidence rates of induced excitations. We relax the frequency-selectivity of excitable media and demonstrate two applications of the method to signals with broadband spectra. Findings obtained from analyzing time series of coupled chaotic oscillators as well as electroencephalographic (EEG) recordings from an epilepsy patient indicate that this method can provide an alternative and complementary way to estimate the degree of phase synchronization in noisy signals.

Time signal distribution in communication networks based on synchronous digital hierarchy

NASA Technical Reports Server (NTRS)

Imaoka, Atsushi; Kihara, Masami

1993-01-01

A new method that uses round-trip paths to accurately measure transmission delay for time synchronization is proposed. The performance of the method in Synchronous Digital Hierarchy networks is discussed. The feature of this method is that it separately measures the initial round trip path delay and the variations in round-trip path delay. The delay generated in SDH equipment is determined by measuring the initial round-trip path delay. In an experiment with actual SDH equipment, the error of initial delay measurement was suppressed to 30ns.

System and method for time synchronization in a wireless network

DOEpatents

Gonia, Patrick S.; Kolavennu, Soumitri N.; Mahasenan, Arun V.; Budampati, Ramakrishna S.

2010-03-30

A system includes multiple wireless nodes forming a cluster in a wireless network, where each wireless node is configured to communicate and exchange data wirelessly based on a clock. One of the wireless nodes is configured to operate as a cluster master. Each of the other wireless nodes is configured to (i) receive time synchronization information from a parent node, (ii) adjust its clock based on the received time synchronization information, and (iii) broadcast time synchronization information based on the time synchronization information received by that wireless node. The time synchronization information received by each of the other wireless nodes is based on time synchronization information provided by the cluster master so that the other wireless nodes substantially synchronize their clocks with the clock of the cluster master.

On Complete Control and Synchronization of Zhang Chaotic System with Uncertain Parameters using Adaptive Control Method

NASA Astrophysics Data System (ADS)

Tirandaz, Hamed

2018-03-01

Chaos control and synchronization of chaotic systems is seemingly a challenging problem and has got a lot of attention in recent years due to its numerous applications in science and industry. This paper concentrates on the control and synchronization problem of the three-dimensional (3D) Zhang chaotic system. At first, an adaptive control law and a parameter estimation law are achieved for controlling the behavior of the Zhang chaotic system. Then, non-identical synchronization of Zhang chaotic system is provided with considering the Lü chaotic system as the follower system. The synchronization problem and parameters identification are achieved by introducing an adaptive control law and a parameters estimation law. Stability analysis of the proposed method is proved by the Lyapanov stability theorem. In addition, the convergence of the estimated parameters to their truly unknown values are evaluated. Finally, some numerical simulations are carried out to illustrate and to validate the effectiveness of the suggested method.

Carrier-frequency synchronization system for improved amplitude modulation and television broadcast reception

DOEpatents

Smith, Stephen F.; Moore, James A.

2003-05-13

Systems and methods are described for carrier-frequency synchronization for improved AM and TV broadcast reception. A method includes synchronizing a carrier frequency of a broadcast signal with a remote reference frequency. An apparatus includes a reference signal receiver; a phase comparator coupled to the reference signal receiver; a voltage controlled oscillator coupled to the phase comparator; and a radio frequency output coupled to the voltage controlled oscillator.

Method and apparatus for a single channel digital communications system. [synchronization of received PCM signal by digital correlation with reference signal

NASA Technical Reports Server (NTRS)

Couvillon, L. A., Jr.; Carl, C.; Goldstein, R. M.; Posner, E. C.; Green, R. R. (Inventor)

1973-01-01

A method and apparatus are described for synchronizing a received PCM communications signal without requiring a separate synchronizing channel. The technique provides digital correlation of the received signal with a reference signal, first with its unmodulated subcarrier and then with a bit sync code modulated subcarrier, where the code sequence length is equal in duration to each data bit.

Robust synchronization control scheme of a population of nonlinear stochastic synthetic genetic oscillators under intrinsic and extrinsic molecular noise via quorum sensing.

PubMed

Chen, Bor-Sen; Hsu, Chih-Yuan

2012-10-26

Collective rhythms of gene regulatory networks have been a subject of considerable interest for biologists and theoreticians, in particular the synchronization of dynamic cells mediated by intercellular communication. Synchronization of a population of synthetic genetic oscillators is an important design in practical applications, because such a population distributed over different host cells needs to exploit molecular phenomena simultaneously in order to emerge a biological phenomenon. However, this synchronization may be corrupted by intrinsic kinetic parameter fluctuations and extrinsic environmental molecular noise. Therefore, robust synchronization is an important design topic in nonlinear stochastic coupled synthetic genetic oscillators with intrinsic kinetic parameter fluctuations and extrinsic molecular noise. Initially, the condition for robust synchronization of synthetic genetic oscillators was derived based on Hamilton Jacobi inequality (HJI). We found that if the synchronization robustness can confer enough intrinsic robustness to tolerate intrinsic parameter fluctuation and extrinsic robustness to filter the environmental noise, then robust synchronization of coupled synthetic genetic oscillators is guaranteed. If the synchronization robustness of a population of nonlinear stochastic coupled synthetic genetic oscillators distributed over different host cells could not be maintained, then robust synchronization could be enhanced by external control input through quorum sensing molecules. In order to simplify the analysis and design of robust synchronization of nonlinear stochastic synthetic genetic oscillators, the fuzzy interpolation method was employed to interpolate several local linear stochastic coupled systems to approximate the nonlinear stochastic coupled system so that the HJI-based synchronization design problem could be replaced by a simple linear matrix inequality (LMI)-based design problem, which could be solved with the help of LMI toolbox in MATLAB easily. If the synchronization robustness criterion, i.e. the synchronization robustness ≥ intrinsic robustness + extrinsic robustness, then the stochastic coupled synthetic oscillators can be robustly synchronized in spite of intrinsic parameter fluctuation and extrinsic noise. If the synchronization robustness criterion is violated, external control scheme by adding inducer can be designed to improve synchronization robustness of coupled synthetic genetic oscillators. The investigated robust synchronization criteria and proposed external control method are useful for a population of coupled synthetic networks with emergent synchronization behavior, especially for multi-cellular, engineered networks.

Robust synchronization control scheme of a population of nonlinear stochastic synthetic genetic oscillators under intrinsic and extrinsic molecular noise via quorum sensing

PubMed Central

2012-01-01

Background Collective rhythms of gene regulatory networks have been a subject of considerable interest for biologists and theoreticians, in particular the synchronization of dynamic cells mediated by intercellular communication. Synchronization of a population of synthetic genetic oscillators is an important design in practical applications, because such a population distributed over different host cells needs to exploit molecular phenomena simultaneously in order to emerge a biological phenomenon. However, this synchronization may be corrupted by intrinsic kinetic parameter fluctuations and extrinsic environmental molecular noise. Therefore, robust synchronization is an important design topic in nonlinear stochastic coupled synthetic genetic oscillators with intrinsic kinetic parameter fluctuations and extrinsic molecular noise. Results Initially, the condition for robust synchronization of synthetic genetic oscillators was derived based on Hamilton Jacobi inequality (HJI). We found that if the synchronization robustness can confer enough intrinsic robustness to tolerate intrinsic parameter fluctuation and extrinsic robustness to filter the environmental noise, then robust synchronization of coupled synthetic genetic oscillators is guaranteed. If the synchronization robustness of a population of nonlinear stochastic coupled synthetic genetic oscillators distributed over different host cells could not be maintained, then robust synchronization could be enhanced by external control input through quorum sensing molecules. In order to simplify the analysis and design of robust synchronization of nonlinear stochastic synthetic genetic oscillators, the fuzzy interpolation method was employed to interpolate several local linear stochastic coupled systems to approximate the nonlinear stochastic coupled system so that the HJI-based synchronization design problem could be replaced by a simple linear matrix inequality (LMI)-based design problem, which could be solved with the help of LMI toolbox in MATLAB easily. Conclusion If the synchronization robustness criterion, i.e. the synchronization robustness ≥ intrinsic robustness + extrinsic robustness, then the stochastic coupled synthetic oscillators can be robustly synchronized in spite of intrinsic parameter fluctuation and extrinsic noise. If the synchronization robustness criterion is violated, external control scheme by adding inducer can be designed to improve synchronization robustness of coupled synthetic genetic oscillators. The investigated robust synchronization criteria and proposed external control method are useful for a population of coupled synthetic networks with emergent synchronization behavior, especially for multi-cellular, engineered networks. PMID:23101662

Mass synchronization: Occurrence and its control with possible applications to brain dynamics

NASA Astrophysics Data System (ADS)

Chandrasekar, V. K.; Sheeba, Jane H.; Lakshmanan, M.

2010-12-01

Occurrence of strong or mass synchronization of a large number of neuronal populations in the brain characterizes its pathological states. In order to establish an understanding of the mechanism underlying such pathological synchronization, we present a model of coupled populations of phase oscillators representing the interacting neuronal populations. Through numerical analysis, we discuss the occurrence of mass synchronization in the model, where a source population which gets strongly synchronized drives the target populations onto mass synchronization. We hypothesize and identify a possible cause for the occurrence of such a synchronization, which is so far unknown: Pathological synchronization is caused not just because of the increase in the strength of coupling between the populations but also because of the strength of the strong synchronization of the drive population. We propose a demand controlled method to control this pathological synchronization by providing a delayed feedback where the strength and frequency of the synchronization determine the strength and the time delay of the feedback. We provide an analytical explanation for the occurrence of pathological synchronization and its control in the thermodynamic limit.

Design and simulation of permanent magnet synchronous motor control system

NASA Astrophysics Data System (ADS)

Li, Li; Liu, Yongqiu

2018-06-01

In recent years, with the development of power electronics, microelectronics, new motor control theory and rare earth permanent magnet materials, permanent magnet synchronous motors have been rapidly applied. Permanent magnet synchronous motors have the advantages of small size, low loss and high efficiency. Today, energy conservation and environmental protection are increasingly valued. It is very necessary to study them. Permanent magnet synchronous motor control system has a wide range of application prospects in the fields of electric vehicles, ships and other transportation. Using the simulation function of MATLAB/SIMULINK, a modular design structure was used to simulate the whole system model of speed loop adjustment, current PI modulation, SVPWM (Space Vector Pulse Width Module) wave generation and double closed loop. The results show that this control method has good robustness, and this method can improve the design efficiency and shorten the system design time. In this article, the analysis of the control principle of modern permanent magnet synchronous motor and the various processes of MATLAB simulation application will be analyzed in detail. The basic theory, basic method and application technology of the permanent magnet synchronous motor control system are systematically introduced.

More About the Phase-Synchronized Enhancement Method

NASA Technical Reports Server (NTRS)

Jong, Jen-Yi

2004-01-01

A report presents further details regarding the subject matter of "Phase-Synchronized Enhancement Method for Engine Diagnostics" (MFS-26435), NASA Tech Briefs, Vol. 22, No. 1 (January 1998), page 54. To recapitulate: The phase-synchronized enhancement method (PSEM) involves the digital resampling of a quasi-periodic signal in synchronism with the instantaneous phase of one of its spectral components. This resampling transforms the quasi-periodic signal into a periodic one more amenable to analysis. It is particularly useful for diagnosis of a rotating machine through analysis of vibration spectra that include components at the fundamental and harmonics of a slightly fluctuating rotation frequency. The report discusses the machinery-signal-analysis problem, outlines the PSEM algorithms, presents the mathematical basis of the PSEM, and presents examples of application of the PSEM in some computational simulations.

Mast cell dynamics in the house rat (Rattus rattus) ovary during estrus cycle, pregnancy and lactation.

PubMed

Batth, B K; Parshad, R K

2000-02-01

The distribution of mast cells in various ovarian compartments was studied during different stages of the reproductive cycles in Rattus rattus. Two types of mast cell populations were recognized with light microscopy i.e., light purple and deep purple, the latter also includes deeply stained cells with extruded granules. Mast cells identified by electron microscopy showed the ultrastructural features during granule formation and release of their content. Significantly higher numbers of mast cells per unit area of ovary were seen at estrus and diestrus. Numbers of mast cells also remained high during pregnancy with possible involvement of mast cell products in vascularization of corpora lutea. A positive correlation existed between mast cell counts and embryo number during pregnancy. However, numbers of mast cells declined significantly after parturition.

Effect of prior insemination of dead sperm and gestation housing management on gilt fertility.

PubMed

Mazzoni, C; De Rensis, F; Kirkwood, R N

2018-05-19

Danbred gilts at about 120 kg were group housed for estrous detection. At detection of estrus, gilts either remained in pens (P) or were re-housed into individual gestation stalls (S) and were inseminated (DS), or not (SC), with a dose of frozen/thawed dead semen. Groups were P-DS (n = 81), P-SC (n = 70), S-DS (n = 98) and S-SC (n = 90). All gilts were inseminated with semen containing viable sperm at the second detected estrus and 24 h later. Pregnant gilts that were stall housed were moved to pens 35 d after insemination. There were no effects of insemination or housing management on farrowing rates or litter sizes. Copyright © 2018. Published by Elsevier B.V.

Factors of a noninfectious nature affecting fertility after artificial insemination in lactating dairy cows. A review.

PubMed

López-Gatius, F

2012-04-01

After 80 years of the commercial application of artificial insemination (AI) in the cow, the method still has numerous benefits over natural insemination including worldwide gene improvement. The efficiency of insemination depends, among many other factors, on the delivery of an appropriate number of normal spermatozoa to the appropriate reproductive tract site at the appropriate time of estrus. The metabolic clearance of steroid hormones and pregnancy associated glycoproteins and the negative effects of different types of stress related to high milk production makes the high-producing dairy cow a good animal model for addressing factors affecting fertility. Nevertheless, extensive studies have shown a positive link between high milk production in an individual cow and high fertility. When a cow becomes pregnant, the effect of pregnancy loss on its reproductive cycle is also a topic of interest. This paper reviews the factors of a noninfectious nature that affect the fertility of lactating dairy cows following AI. Special attention is paid to factors related to the cow and its environment and to estrus confirmation at insemination. Pregnancy maintenance during the late embryonic/early fetal period is discussed as a critical step. Finally, the use of Doppler ultrasonography is described as an available research tool for improving our current understanding of the health of the genital structures and conceptus. Copyright © 2012 Elsevier Inc. All rights reserved.

Adaptive Synchronization of Fractional Order Complex-Variable Dynamical Networks via Pinning Control

NASA Astrophysics Data System (ADS)

Ding, Da-Wei; Yan, Jie; Wang, Nian; Liang, Dong

2017-09-01

In this paper, the synchronization of fractional order complex-variable dynamical networks is studied using an adaptive pinning control strategy based on close center degree. Some effective criteria for global synchronization of fractional order complex-variable dynamical networks are derived based on the Lyapunov stability theory. From the theoretical analysis, one concludes that under appropriate conditions, the complex-variable dynamical networks can realize the global synchronization by using the proper adaptive pinning control method. Meanwhile, we succeed in solving the problem about how much coupling strength should be applied to ensure the synchronization of the fractional order complex networks. Therefore, compared with the existing results, the synchronization method in this paper is more general and convenient. This result extends the synchronization condition of the real-variable dynamical networks to the complex-valued field, which makes our research more practical. Finally, two simulation examples show that the derived theoretical results are valid and the proposed adaptive pinning method is effective. Supported by National Natural Science Foundation of China under Grant No. 61201227, National Natural Science Foundation of China Guangdong Joint Fund under Grant No. U1201255, the Natural Science Foundation of Anhui Province under Grant No. 1208085MF93, 211 Innovation Team of Anhui University under Grant Nos. KJTD007A and KJTD001B, and also supported by Chinese Scholarship Council

Illumination-based synchronization of high-speed vision sensors.

PubMed

Hou, Lei; Kagami, Shingo; Hashimoto, Koichi

2010-01-01

To acquire images of dynamic scenes from multiple points of view simultaneously, the acquisition time of vision sensors should be synchronized. This paper describes an illumination-based synchronization method derived from the phase-locked loop (PLL) algorithm. Incident light to a vision sensor from an intensity-modulated illumination source serves as the reference signal for synchronization. Analog and digital computation within the vision sensor forms a PLL to regulate the output signal, which corresponds to the vision frame timing, to be synchronized with the reference. Simulated and experimental results show that a 1,000 Hz frame rate vision sensor was successfully synchronized with 32 μs jitters.

Motif-Synchronization: A new method for analysis of dynamic brain networks with EEG

NASA Astrophysics Data System (ADS)

Rosário, R. S.; Cardoso, P. T.; Muñoz, M. A.; Montoya, P.; Miranda, J. G. V.

2015-12-01

The major aim of this work was to propose a new association method known as Motif-Synchronization. This method was developed to provide information about the synchronization degree and direction between two nodes of a network by counting the number of occurrences of some patterns between any two time series. The second objective of this work was to present a new methodology for the analysis of dynamic brain networks, by combining the Time-Varying Graph (TVG) method with a directional association method. We further applied the new algorithms to a set of human electroencephalogram (EEG) signals to perform a dynamic analysis of the brain functional networks (BFN).

Oviductal extracellular vesicles (oviductosomes, OVS) are conserved in humans: murine OVS play a pivotal role in sperm capacitation and fertility.

PubMed

Bathala, Pradeepthi; Fereshteh, Zeinab; Li, Kun; Al-Dossary, Amal A; Galileo, Deni S; Martin-DeLeon, Patricia A

2018-03-01

Are extracellular vesicles (EVs) in the murine oviduct (oviductosomes, OVS) conserved in humans and do they play a role in the fertility of Pmca4-/- females? OVS and their fertility-modulating proteins are conserved in humans, arise via the apocrine pathway, and mediate a compensatory upregulation of PMCA1 (plasma membrane Ca2+-ATPase 1) in Pmca4-/- female mice during proestrus/estrus, to account for their fertility. Recently murine OVS were identified and shown during proestrus/estrus to express elevated levels of PMCA4 which they can deliver to sperm. PMCA4 is the major Ca2+ efflux pump in murine sperm and Pmca4 deletion leads to loss of sperm motility and male infertility as there is no compensatory upregulation of the remaining Ca2+ pump, PMCA1. Of the four family members of PMCAs (PMCA1-4), PMCA1 and PMCA4 are ubiquitous, and to date there have been no reports of one isoform being upregulated to compensate for another in any organ/tissue. Since Pmca4-/- females are fertile, despite the abundant expression of PMCA4 in wild-type (WT) OVS, we propose that OVS serve a role of packaging and delivering to sperm elevated levels of PMCA1 in Pmca4-/- during proestrus/estrus to compensate for PMCA4's absence. Fallopian tubes from pre-menopausal women undergoing hysterectomy were used to study EVs in the luminal fluid. Oviducts from sexually mature WT mice were sectioned after perfusion fixation to detect EVs in situ. Oviducts were recovered from WT and Pmca4-/- after hormonally induced estrus and sectioned for PMCA1 immunofluorescence (IF) (detected with confocal microscopy) and hematoxylin and eosin staining. Reproductive tissues, luminal fluids and EVs were recovered after induced estrus and after natural cycling for western blot analysis of PMCA1 and qRT-PCR of Pmca1 to compare expression levels in WT and Pmca4-/-. OVS, uterosomes, and epididymal luminal fluid were included in the comparisons. WT and Pmca4-/- OVS were analyzed for the presence of known PMCA4 partners in sperm and their ability to interact with PMCA1, via co-immunoprecipitation. In vitro uptake of PMCA1 from OVS was analyzed in capacitated and uncapacitated sperm via quantitative western blot analysis, IF localization and flow cytometry. Caudal sperm were also assayed for uptake of tyrosine-phosphorylated proteins which were shown to be present in OVS. Finally, PMCA1 and PMCA4 in OVS and that delivered to sperm were assayed for enzymatic activity. Human fallopian tubes were flushed to recover luminal fluid which was processed for OVS via ultracentrifugation. Human OVS were negatively stained for transmission electron microscopy (TEM) and subjected to immunogold labeling, to detect PMCA4. Western analysis was used to detect HSC70 (an EV biomarker), PMCA1 and endothelial nitric oxide synthase (eNOS) which is a fertility-modulating protein delivered to human sperm by prostasomes. Oviducts of sexually mature female mice were sectioned after perfusion fixation for TEM tomography to obtain 3D information and to distinguish cross-sections of EVs from those of microvilli and cilia. Murine tissues, luminal fluids and EVs were assayed for PMCA1 (IF and western blot) or qRT-PCR. PMCA1 levels from western blots were quantified, using band densities and compared in WT and Pmca4-/- after induced estrus and in proestrus/estrus and metestrus/diestrus in cycling females. In vitro uptake of PMCA1 and tyrosine-phosphorylated proteins was quantified with flow cytometry and/or quantitative western blot. Ca2+-ATPase activity in OVS and sperm before and after PMCA1 and PMCA4 uptake was assayed, via the enzymatic hydrolysis rate of ATP. TEM revealed that human oviducts contain EVs (exosomal and microvesicular). These EVs contain PMCA4 (immunolabeling), eNOS and PMCA1 (western blot) in their cargo. TEM tomography showed the murine oviduct with EV-containing blebs which typify the apocrine pathway for EV biogenesis. Western blots revealed that during proestrus/estrus PMCA1 was significantly elevated in the oviductal luminal fluid (OLF) (P = 0.02) and in OVS (P = 0.03) of Pmca4-/-, compared to WT. Further, while PMCA1 levels did not fluctuate in OLF during the cycle in WT, they were significantly (P = 0.02) higher in proestrus/estrus than at metestrus/diestrus in Pmca4-/-. The elevated levels of PMCA1 in proestrus/estrus, which mimics PMCA4 in WT, is OLF/OVS-specific, and is not seen in oviductal tissues, uterosomes or epididymal luminal fluid of Pmca4-/-. However, qRT-PCR revealed significantly elevated levels of Pmca1 transcript in Pmca4-/- oviductal tissues, compared to WT. PMCA1 could be transferred from OVS to sperm and the levels were significantly higher for capacitated vs uncapacitated sperm, as assessed by flow cytometry (P = 0.001) after 3 h co-incubation, quantitative western blot (P < 0.05) and the frequency of immuno-labeled sperm (P < 0.001) after 30 min co-incubation. Tyrosine phosphorylated proteins were discovered in murine OVS and could be delivered to sperm after their co-incubation with OVS, as detected by western, immunofluorescence localization, and flow cytometry. PMCA1 and PMCA4 in OVS were shown to be enzymatically active and this activity increased in sperm after OVS interaction. None. Although oviductal tissues of WT and Pmca4-/- showed no significant difference in PMCA1 levels, Pmca4-/- levels of OVS/OLF during proestrus/estrus were significantly higher than in WT. We have attributed this enrichment or upregulation of PMCA1 in Pmca4-/- partly to selective packaging in OVS to compensate for the lack of PMCA4. However, in the absence of a difference between WT and Pmca4-/- in the PMCA1 levels in oviductal tissues as a whole, we cannot rule out significantly higher PMCA1 expression in the oviductal epithelium that gives rise to the OVS as significantly higher Pmca1 transcripts were detected in Pmca4-/-. Since OVS and fertility-modulating cargo components are conserved in humans, it suggests that murine OVS role in regulating the expression of proteins required for capacitation and fertility is also conserved. Secondly, OVS may explain some of the differences in in vivo and in vitro fertilization for mouse mutants, as seen in mice lacking the gene for FER which is the enzyme required for sperm protein tyrosine phosphorylation. Our observation that murine OVS carry and can modulate sperm protein tyrosine phosphorylation by delivering them to sperm provides an explanation for the in vivo fertility of Fer mutants, not seen in vitro. Finally, our findings have implications for infertility treatment and exosome therapeutics. The work was supported by National Institute of Health (RO3HD073523 and 5P20RR015588) grants to P.A.M.-D. There are no conflicts of interests.

Cryptographic synchronization recovery by measuring randomness of decrypted data

DOEpatents

Maestas, Joseph H.; Pierson, Lyndon G.

1990-01-01

The invention relates to synchronization of encrypted data communication systems and a method which looks for any lack of pattern or intelligent information in the received data and triggers a resynchronization signal based thereon. If the encrypter/decrypter pairs are out of cryptographic synchronization, the received (decrypted) data resembles pseudorandom data. A method and system are provided for detecting such pseudorandom binary data by, for example, ones density. If the data is sufficiently random the system is resynchronized.

21 CFR 520.1430 - Mibolerone.

Code of Federal Regulations, 2014 CFR

2014-04-01

... for use. For the prevention of estrus (heat) in adult female dogs not intended primarily for breeding... being used primarily for breeding purposes. Use orally in adult female dogs only. Federal law restricts...

21 CFR 520.1430 - Mibolerone.

Code of Federal Regulations, 2012 CFR

2012-04-01

... for use. For the prevention of estrus (heat) in adult female dogs not intended primarily for breeding... being used primarily for breeding purposes. Use orally in adult female dogs only. Federal law restricts...

21 CFR 520.1430 - Mibolerone.

Code of Federal Regulations, 2011 CFR

2011-04-01

... for use. For the prevention of estrus (heat) in adult female dogs not intended primarily for breeding... being used primarily for breeding purposes. Use orally in adult female dogs only. Federal law restricts...

21 CFR 520.1430 - Mibolerone.

Code of Federal Regulations, 2013 CFR

2013-04-01

... for use. For the prevention of estrus (heat) in adult female dogs not intended primarily for breeding... being used primarily for breeding purposes. Use orally in adult female dogs only. Federal law restricts...

A new strategy for superior reproductive performance of ewes bred out-of-season utilizing progestagen supplement prior to withdrawal of intravaginal pessaries.

PubMed

Husein, M Q; Ababneh, M M

2008-02-01

Two experiments were conducted to examine the effect of progestagen supplement 24h prior to intravaginal pessary withdrawal on reproductive performance of seasonal anestrous ewes. Ewes in each experiment were allocated to treatment and control and all were induced to estrus using either intravaginal MAP (Exp. 1; n=24) or CIDR-G (Exp. 2; n=28) pessaries for 12 days. Half of the ewes in each experiment were supplemented 24h before withdrawal of pessaries with either 10mg oral MAP tablets (Exp. 1) or 25mg i.m. progesterone (P(4)) administration (Exp. 2; P(4)-supplement-treated group). Fertile rams were allowed with the ewes at sponge removal (Day 0, 0h) and estrus was monitored at 6-h intervals for 3 days. Blood samples were collected for measurements of P(4) (Exp. 1 and Exp. 2) and LH (Exp. 2). In both experiments, the percent of ewes in estrus was greater (P<0.05) and intervals to estrus were longer (P<0.05) in progestagen-supplement-treated than control ewes. In Exp. 2, the occurrence and magnitude of LH surges were greater (P<0.01) and intervals to onset of LH surge were longer (P<0.01) in P(4)-supplement-treated than control ewes. In Exp. 2, P(4) supplement elevated P(4) levels from 1.8+/-0.1ng/mL on Day -1 to 4.2+/-0.3 on Day 0 (P<0.001). Following pessaries removal, P(4) concentrations fell to basal values on Day 1 in both groups and remained low until Day 5. Then, P(4) concentrations increased and remained elevated through Day 19 in all (100%) progestagen-supplement-treated in Exp. 1 (12/12) and Exp. 2 (14/14) and in only 5/12 (41.7%) and 6/14 (42.9%) control ewes, respectively. These ewes were confirmed pregnant by ultrasonography and lambed on Day 149.2+/-0.2 following Day 0. In conclusion, progestagen supplement 24h prior to removal of pessary can be used successfully to improve reproductive performance of ewes bred out-of-season.

Prostaglandin F2alpha-induced estrus in ewes exhibiting estrous cycles of different duration.

PubMed

Cárdenas, Horacio; Wiley, Todd M; Pope, William F

2004-07-01

Effects of prostaglandin F(2alpha) (PGF(2alpha)), administered during the mid-luteal phase of the estrous cycle, were examined in ewes exhibiting estrous cycles classified as short (< or =16.5 days, short-cycle ewes, n = 10) or long (> or =18 days, long-cycle ewes, n = 9) based on the durations of two estrous cycles (cycles -2 and -1) before treatment. The ewes received (i.m.) 20mg of PGF(2alpha) on day 10 of the third estrous cycle (cycle 0) followed, 36 h later, by 25 microg of gonadotropin releasing hormone (GnRH) to time the events of ovulation. Duration of subsequent estrous cycles +1 and +2 were recorded, and then the ewes were treated with the same combination of PGF(2alpha) and GnRH beginning on day 10 of estrous cycle +3. Ovaries were recovered 6h after GnRH administration to assess development of pre-ovulatory follicles. The proportion of ewes that exhibited estrus after PGF(2alpha) and GnRH treatment on cycle 0 was not different (P > 0.05) between short- and long-cycle ewes. Onset of estrus occurred sooner (P < 0.05) after PGF(2alpha) injection in short-cycle ewes than in long-cycle ewes (1.9 +/- 0.1 days and 2.3 +/- 0.1 days, duration of cycle 0 was 11.9 and 12.3 days, respectively). Duration of estrous cycle +1 was 1.2 days longer (P < 0.01) than cycle -1 in short-cycle ewes. However, duration of estrous cycle +1 did not change (P > 0.05) after PGF(2alpha) and GnRH administration in ewes having long cycles. Pre-ovulatory follicles did not differ (P > 0.05) in numbers, diameter, layers of granulosa cells nor concentrations of progesterone and estradiol-17beta in follicular fluid between short- and long-cycle ewes after PGF(2alpha) and GnRH treatment. In conclusion, ewes having short or long estrous cycles responded differently to PGF(2alpha) and GnRH treatment with respect to the interval to onset of estrus and duration of the subsequent estrous cycle.

The ischiorectal fossa: an alternative route for the administration of prostaglandin in cattle

PubMed Central

Colazo, Marcos G.; MartÍnez, Marcelo F.; Kastelic, John P.; Mapletoft, Reuben J.; Carruthers, Terry D.

2002-01-01

Three experiments were conducted to investigate the ischiorectal fossa (IRF) as a route for the administration of prostaglandin F2α (dinoprost) in cattle. In Experiment 1, 21 nonlactating Holstein cows were given 100 μg of gonadotropin releasing hormone (GnRH), intramuscularly (IM), and, 7 d later, 25 mg of dinoprost into the IRF. Sixteen cows had serum progesterone concentrations ≥ 1.0 ng/mL at the time of dinoprost treatment, and all of these had rapid and complete luteolysis; the other 5 cows were not considered to have a functional corpus luteum (CL) at the time of treatment. There were minimal adverse behavioral reactions to the IRF injections and no visible or palpable tissue reactions at the injection site. In Experiment 2, 74 Holstein heifers were given 25 mg of dinoprost by IRF injection. Luteolysis occurred in 84.3% of the heifers with a functional CL (as determined by the serum progesterone concentration at the time of treatment). Of the heifers bred by either natural service or artificial insemination, 61.8% became pregnant. In Experiment 3, 48 beef heifers received dinoprost 7 d after ovulation, as follows: 25 mg, IM (n = 9); 25 mg, IRF (n = 10); 10 mg, IRF (n = 10); 10 mg, subcutaneously (SC) (n = 10); or 10 mg, intravulvosubmucosally (IVSM) (n = 9). Fewer heifers (P < 0.05) were found to be in estrus or ovulating in the 10 mg IVSM group (0% and 11%, respectively) than in the 25 mg IM group (100% and 100%), the 25 mg IRF group (90% and 100%, respectively), or the 10 mg IRF group (80% and 80%). The rates of estrus (50%) and ovulation (50%) were intermediate in the 10 mg SC group. In summary, 25 mg of dinoprost injected into the IRF caused minimal behavioral or tissue response and induced luteolysis and fertile estrus. In addition, 10 mg of dinoprost injected into the IRF was as efficacious as 25 mg given either IM or into the IRF in inducing estrus and ovulation. PMID:12125185

Estrus behavior, ovarian dynamics, and progesterone secretion in Criollo cattle during estrous cycles with two and three follicular waves.

PubMed

Quezada-Casasola, Andrés; Avendaño-Reyes, Leonel; Macías-Cruz, Ulises; Ramírez-Godínez, José Alejandro; Correa-Calderón, Abelardo

2014-04-01

In beef and dairy cattle, the number of follicular waves affects endocrine, ovarian, and behavioral events during a normal estrous cycle. However, in Mexican-native Criollo cattle, a shortly and recently domesticated breed, the association between wave patterns and follicular development has not been studied. The objective of this study was to evaluate the effect of number of follicular waves in an estrous cycle on development of anovulatory and ovulatory follicles, corpus luteum (CL) development and functionality, as well as estrual behavior in Criollo cows. Ovarian follicular activities of 22 cycling multiparous Criollo cows were recorded daily by transrectal ultrasound examinations during a complete estrous cycle. Additionally, blood samples were collected daily to determine serum progesterone concentrations. Only two- (n = 17, 77.3%) and three-wave follicular (n = 5, 22.7%) patterns were observed. Duration of estrus, length of estrous cycle, and length of follicular and luteal phases were similar (P > 0.05) between cycles of two and three waves. Two-wave cows ovulated earlier (P < 0.05) after detection of estrus than three-wave cows. Detected day and maximum diameter of first anovulatory follicle were not affected (P > 0.05) by number of waves. Growth rate of first dominant follicle was higher (P < 0.05) in three-wave cycles. Onset of regression of the first dominant follicle was earlier (P < 0.01) in cycles with three waves than in those with two waves. In two-wave cycles, ovulatory follicles were detected earlier (P < 0.01) and had lower (P < 0.01) growth rate than in three-wave cycles. Development (i.e., maximum diameter and volume) and functionality (minimum and maximum progesterone concentration) of CL were similar (P > 0.05) between two- and three-wave patterns. In conclusion, Criollo cows have two or three follicular waves per estrous cycle, which alters partially ovulatory follicle development and ovulation time after detection of estrus. Length of estrous cycle, as well as CL development and functionality, was not affected by number of follicular waves.

Expression and secretion of plasma membrane Ca2+-ATPase 4a (PMCA4a) during murine estrus: association with oviductal exosomes and uptake in sperm.

PubMed

Al-Dossary, Amal A; Strehler, Emanuel E; Martin-Deleon, Patricia A

2013-01-01

PMCA4, a membrane protein, is the major Ca(2+) efflux pump in murine sperm where its deletion leads to a severe loss of hyperactivated motility and to male infertility. We have previously shown that the PMCA4b splice variant interacts with CASK (Ca(2+/)CaM-dependent serine kinase) in regulating sperm Ca(2+). More recently we detected that PMCA4a isoform, in addition to its presence in testis, is secreted in the epididymal luminal fluid and transferred to sperm. Here we show that Pmca4 mRNA is expressed in both the 4a and 4b variants in the vagina, uterus, and oviduct. Immunofluorescence reveals that PMCA4a is similarly expressed and is elevated during estrus, appearing in the glandular and luminal epithelia. Western analysis detected PMCA4a in all tissues and in the luminal fluids (LF) of the vagina (VLF), uterus (ULF), and the oviduct (OLF) collected during estrus. It was ~9- and 4-fold higher in OLF than in VLF and ULF, and only marginally present in LF collected at metestrus/diestrus. Fractionation of the LF collected at estrus, via ultracentrifugation, revealed that 100% of the PMCA4a resides in the vesicular fraction of the ULF and OLF. Transmission electron microscopy (TEM) revealed that OLF vesicles have an exosomal orientation (with the cytoplasmic-side inward), a size range of 25-100 nm, with the characteristic CD9 biomarker. Thus, we dubbed these vesicles "oviductosomes", to which PMCA4a was immunolocalized. Incubation of caudal sperm in the combined LF or exosomes resulted in up to a ~3-fold increase of sperm PMCA4a, as detected by flow cytometry, indicating in vitro uptake. Our results are consistent with the increased requirement of Ca(2+) efflux in the oviduct. They show for the first time the presence of oviductal exosomes and highlight their role, along with uterosomes and vaginal exosomes, in post-testicular sperm acquisition of PMCA4a which is essential for hyperactivated motility and fertility.

Expression and Secretion of Plasma Membrane Ca2+-ATPase 4a (PMCA4a) during Murine Estrus: Association with Oviductal Exosomes and Uptake in Sperm

PubMed Central

Al-Dossary, Amal A.; Strehler, Emanuel E.; Martin-DeLeon, Patricia A.

2013-01-01

PMCA4, a membrane protein, is the major Ca2+ efflux pump in murine sperm where its deletion leads to a severe loss of hyperactivated motility and to male infertility. We have previously shown that the PMCA4b splice variant interacts with CASK (Ca2+/CaM-dependent serine kinase) in regulating sperm Ca2+. More recently we detected that PMCA4a isoform, in addition to its presence in testis, is secreted in the epididymal luminal fluid and transferred to sperm. Here we show that Pmca4 mRNA is expressed in both the 4a and 4b variants in the vagina, uterus, and oviduct. Immunofluorescence reveals that PMCA4a is similarly expressed and is elevated during estrus, appearing in the glandular and luminal epithelia. Western analysis detected PMCA4a in all tissues and in the luminal fluids (LF) of the vagina (VLF), uterus (ULF), and the oviduct (OLF) collected during estrus. It was ~9- and 4-fold higher in OLF than in VLF and ULF, and only marginally present in LF collected at metestrus/diestrus. Fractionation of the LF collected at estrus, via ultracentrifugation, revealed that 100% of the PMCA4a resides in the vesicular fraction of the ULF and OLF. Transmission electron microscopy (TEM) revealed that OLF vesicles have an exosomal orientation (with the cytoplasmic-side inward), a size range of 25-100 nm, with the characteristic CD9 biomarker. Thus, we dubbed these vesicles “oviductosomes”, to which PMCA4a was immunolocalized. Incubation of caudal sperm in the combined LF or exosomes resulted in up to a ~3-fold increase of sperm PMCA4a, as detected by flow cytometry, indicating in vitro uptake. Our results are consistent with the increased requirement of Ca2+ efflux in the oviduct. They show for the first time the presence of oviductal exosomes and highlight their role, along with uterosomes and vaginal exosomes, in post-testicular sperm acquisition of PMCA4a which is essential for hyperactivated motility and fertility. PMID:24244642

Immuno-histochemical localization of LH-RH during different phases of estrus cycle of rat, with reference to the preoptic and arcuate neurons, and the ependymal cells.

PubMed

Naik, D V

1976-10-06

Immunohistochemical localization of luteinizing hormone-releasing hormone (LH-RH), during different phases of the estrus cycle, in the preoptic, suprachiasmatic and arcuate nuclei, and in the OVLT of rats, with special emphasis on the ependymal cells, was studied by light, fluorescent and electron microscopy, by using rabbit anti serum to synthetic LH-RH. The LH-RH neurons in the above mentioned areas, were very active during late diestrus and early proestrus phases. Specialized ependymal cells bordering the 3rd ventricle also showed varied LH-RH positive reaction during different phases of the estrus cycle. Immunofluorescent studies showed cyclic variations in the LH-RH material in the CSF of the preoptic and infundibular recesses, as well as in the 3rd ventricle near OVLT, in that, it was maximum during late diestrus and early proestrus phases. Immediately after this, the LH-RH late proestrus was reached. We have also observed that during the proestrus phase, as the LH-RH material started declining in the CSF, it had started building up in the specialized ependyma. Estrus, metaestrus and early diestrus phases showed very weak immunofluorescent LH-RH material in the lumen of the infundibular recess and in the specialized ependyma. Our immuno-electron microscopic observations showed pleomorphic LH-RH granules in the specialized ependyma during late kiestrus and proestrus phases. All these observations lead us to believe that LH-RH is not synthesized in the ependymal cells,but is phagocytosed from the CSF of the 3rd ventricle by the specialized ependyma, which transports it to the ME portal system. In males, the fluorescent LH-RH material did not show any noticeable changes. With the present and previous work,it is concluded that the neurons in differentnuclei synthesize LH-RH and transport it to the ME portal system,primarily through the nerve fibers and secondarily by the ventricular route. It is also suggested that the ependymal transport of LH-RH to the ME portal system is cyclic and thus controls the gonadotropin secretion.

The hamster clock phase-response curve from summerlike light:dark cycles and its role in daily and seasonal timekeeping.

PubMed

Alleva, John J; Alleva, Frederic R

2002-11-01

We address the subject of entrainment of the hamster clock by the day:night cycle in summer when the sun sets after 6 PM and rises before 6 AM (nights < 12 h). Summer day:night cycles were simulated by 6 light:dark (LD) cycles with D < 12 h (summerlike, SLD) ranging from SLD 12.5 h:11.5 h (D, 6:15 PM-5:45 AM) to 18 h:6 h (D, 9 PM-3 AM). These are the near limiting SLDs for constant PM timing (entrainment) of behavioral estrus and wheel running in hamsters. The onset of estrus was observed every 4 d in the same hamsters as a phase marker of their 24 h clock. On the day before an experimental estrus, preceded and followed by control onsets, a dark period was imposed to cover a putative 6 PM-6 AM light-sensitive period (LSP). This was scanned with a light pulse (and periodic 5 sec bell alarms) lasting 5-240 min. Shifts in onset of estrus on the next day were plotted vs. the end of the light pulse for PM times ("dusk") and its onset for AM times ("dawn"). The resulting phase shifts from the six SLDs were similar, permitting their combination into a single phase-response curve (PRC) of 1605 shifts. This SLD composite PRC rose at 10:15 PM, peaked at 2 AM (81 min advanced shift), fell linearly to 5:55 AM, and then abruptly to normal at 6 AM (no shift). Peak shift was unaffected by light pulse duration or intensity, or hamster age. The SLD composite PRC lacked the 6 PM-9 PM curve of delayed shifts present in reported PRCs from LD 12 h:12 h and DD. However, a two-pulse experiment showed that all light from 6 PM to L-off was needed to block (balance) the advancing action of a 5 min morning light pulse, thereby maintaining entrainment. A working hypothesis to explain daily entrainment and seasonal fertility in the golden hamster is illustrated. A nomenclature for labeling the phases of the hamster clock (circadian time) is proposed.

Non-invasive endocrine monitoring of ovarian and adrenal activity in chinchilla (Chinchilla lanigera) females during pregnancy, parturition and early post-partum period.

PubMed

Mastromonaco, Gabriela F; Cantarelli, Verónica I; Galeano, María G; Bourguignon, Nadia S; Gilman, Christine; Ponzio, Marina F

2015-03-01

The chinchilla is a rodent that bears one of the finest and most valuable pelts in the world. The wild counterpart is, however, almost extinct because of a drastic past and ongoing population decline. The present work was developed to increase our knowledge of the reproductive physiology of pregnancy and post-partum estrus in the chinchilla, characterizing the endocrine patterns of urinary progesterone, estradiol, LH and cortisol metabolites throughout gestation and post-partum estrus and estimating the ovulation timing at post-partum estrus. Longitudinal urine samples were collected once per week throughout pregnancy and analyzed for creatinine, cortisol, LH, estrogen and progesterone metabolite concentrations. To indirectly determine the ovulation timing at post-partum estrus, a second experiment was performed using pregnant females subjected to a post-partum in vivo fertilization scheme. Urinary progestagen metabolites increased above baseline levels in early pregnancy between weeks-8 and -11 respectively to parturition, and slightly declined at parturition time. Urinary estrogens showed rising levels throughout mid- and late pregnancy (weeks-9 to -6 and a further increase at week-5 to parturition) and decreased in a stepwise manner after parturition, returning to baseline levels two weeks thereafter. Cortisol metabolite levels were relatively constant throughout pregnancy with a tendency for higher levels in the last third of gestation and after the pups' birth. Parturition was associated with dramatic reductions in urinary concentrations of sex steroids (especially progestagens). Observations in breeding farms indicated that the females that resulted in a second pregnancy after mating, did so on the second day after parturition. These data were in agreement with an LH peak detected 24h after parturition. Urinary steroid hormone patterns of estrogen and progestagen metabolites provided valuable information on endocrine events during pregnancy and after parturition in the chinchilla. Results presented in this study enhance our understanding of natural reproductive dynamics in the chinchilla and support empirical observations of breeders that post-partum ovulation occurs ∼ 48 h after parturition. Copyright © 2015 Elsevier Inc. All rights reserved.

Aspects of sexual precocity and morphometry of uterus, placenta and embryos/fetuses in Piau breed and Commercial line gilts.

PubMed

Montes, José Carlos; Penitente-Filho, Jurandy Mauro; Guimarães, Simone Eliza Facioni; Lopes, Paulo Sávio; Camilo, Breno Soares; Shiomi, Hugo Hideki; Lima, Daniel Araújo; Pinho, Rogério Oliveira; Pereira, Jhonata Vieira Tavares do Nascimento; Okano, Denise Silva; Costa, Karine Assis; Guimarães, José Domingos

2018-01-01

In view of the importance of the genetic material of local breeds in the swine industry and the lack of information about reproductive performance of Piau females, two experiments were conducted to evaluate puberty and sexual maturity as well as the morphometry of embryos/fetuses, placenta and uterus during the first 90 days of gestation in Piau breed and Commercial line gilts. In experiment I, 37 Piau and 25 commercial line gilts were used. From the 120 days of age, detection of estrus was performed using mature boars from the first to third estrus of each gilt. Data regarding to age, body weight and estrus duration were recorded. After third estrus, females were slaughtered and ovaries were collected to determine ovulation rate. In experiment II, 36 Piau and 18 commercial line gilts were distributed into three groups according to the mating: Commercial, commercial line females x commercial line male; cross-mated, Piau females x commercial line male; and Piau, Piau females x Piau male. Gilts were slaughtered at 7, 15, 30, 45, 60 and 90 days of pregnancy. Piau females reached puberty and sexual maturity at the same age as commercial line females, but with lower weight; moreover, Piau group showed negative correlations of birth weight with puberty (-0.27) and sexual maturity (-0.29). Commercial gilts presented higher ovulation rate, weight and length of uterus, and length and thoracic circumference of fetuses. Nevertheless, number of fetuses was similar in all groups at 90 days of gestation suggesting that Piau females present higher survival rates of the conceptuses. The results showed differences between the genetic groups related to fetal and placental development, gestational losses, number of ovulations and uterine development. In addition, an intermediate status of fetal weight was observed in Piau/Commercial line crossbred conceptuses; thus, the selection of Piau females on reproductive traits to be mated with commercial line males would be an alternative to contribute to improvement of intramuscular fat content. Copyright © 2017. Published by Elsevier Inc.

Magnetic isolation of Plasmodium falciparum schizonts iRBCs to generate a high parasitaemia and synchronized in vitro culture.

PubMed

Mata-Cantero, Lydia; Lafuente, Maria J; Sanz, Laura; Rodriguez, Manuel S

2014-03-21

The establishment of methods for an in vitro continuous culture of Plasmodium falciparum is essential for gaining knowledge into its biology and for the development of new treatments. Previously, several techniques have been used to synchronize, enrich and concentrate P. falciparum, although obtaining cultures with high parasitaemia continues being a challenging process. Current methods produce high parasitaemia levels of synchronized P. falciparum cultures by frequent changes of culture medium or reducing the haematocrit. However, these methods are time consuming and sometimes lead to the loss of synchrony. A procedure that combines Percoll and sorbitol treatments, the use of magnetic columns, and the optimization of the in vitro culture conditions to reach high parasitaemia levels for synchronized Plasmodium falciparum cultures is described. A new procedure has been established using P. falciparum 3D7, combining previous reported methodologies to achieve in vitro parasite cultures that reach parasitaemia up to 40% at any intra-erythrocytic stage. High parasitaemia levels are obtained only one day after magnetic column purification without compromising the parasite viability and synchrony. The described procedure allows obtaining a large scale synchronized parasite culture at a high parasitaemia with less manipulations than other methods previously described.

Design and implementation of EP-based PID controller for chaos synchronization of Rikitake circuit systems.

PubMed

Hou, Yi-You

2017-09-01

This article addresses an evolutionary programming (EP) algorithm technique-based and proportional-integral-derivative (PID) control methods are established to guarantee synchronization of the master and slave Rikitake chaotic systems. For PID synchronous control, the evolutionary programming (EP) algorithm is used to find the optimal PID controller parameters k p , k i , k d by integrated absolute error (IAE) method for the convergence conditions. In order to verify the system performance, the basic electronic components containing operational amplifiers (OPAs), resistors, and capacitors are used to implement the proposed chaotic Rikitake systems. Finally, the experimental results validate the proposed Rikitake chaotic synchronization approach. Copyright © 2017. Published by Elsevier Ltd.

Effects of Synchronous Rolling on Microstructure, Hardness, and Wear Resistance of Laser Multilayer Cladding

NASA Astrophysics Data System (ADS)

Zhao, W.; Zha, G. C.; Xi, M. Z.; Gao, S. Y.

2018-03-01

A synchronous rolling method was proposed to assist laser multilayer cladding, and the effects of this method on microstructure, microhardness, and wear resistance were studied. Results show that the microstructure and mechanical properties of the traditional cladding layer exhibit periodic inhomogeneity. Synchronous rolling breaks the columnar dendrite crystals to improve the uniformity of the organization, and the residual plastic energy promotes the precipitation of strengthening phases, as CrB, M7C3, etc. The hardness and wear resistance of the extruded cladding layer increase significantly because of the grain refinement, formation of dislocations, and dispersion strengthening. These positive significances of synchronous rolling provide a new direction for laser cladding technology.

Phase synchronization based on a Dual-Tree Complex Wavelet Transform

NASA Astrophysics Data System (ADS)

Ferreira, Maria Teodora; Domingues, Margarete Oliveira; Macau, Elbert E. N.

2016-11-01

In this work, we show the applicability of our Discrete Complex Wavelet Approach (DCWA) to verify the phenomenon of phase synchronization transition in two coupled chaotic Lorenz systems. DCWA is based on the phase assignment from complex wavelet coefficients obtained by using a Dual-Tree Complex Wavelet Transform (DT-CWT). We analyzed two coupled chaotic Lorenz systems, aiming to detect the transition from non-phase synchronization to phase synchronization. In addition, we check how good is the method in detecting periods of 2π phase-slips. In all experiments, DCWA is compared with classical phase detection methods such as the ones based on arctangent and Hilbert transform showing a much better performance.

The Integration of Linguistic Theory: Internal Reconstruction and the Comparative Method in Descriptive Linguistics.

ERIC Educational Resources Information Center

Bailey, Charles-James N.

The author aims: (1) to show that generative phonology uses essentially the method of internal reconstruction which has previously been employed only in diachronic studies in setting up synchronic underlying phonological representations; (2) to show why synchronic analysis should add the comparative method to its arsenal, together with whatever…

Adaptive feedback synchronization of a unified chaotic system

NASA Astrophysics Data System (ADS)

Lu, Junan; Wu, Xiaoqun; Han, Xiuping; Lü, Jinhu

2004-08-01

This Letter further improves and extends the work of Wang et al. [Phys. Lett. A 312 (2003) 34]. In detailed, the linear feedback synchronization and adaptive feedback synchronization with only one controller for a unified chaotic system are discussed here. It is noticed that this unified system contains the noted Lorenz and Chen systems. Two chaotic synchronization theorems are attained. Also, numerical simulations are given to show the effectiveness of these methods.

Function projective synchronization in chaotic and hyperchaotic systems through open-plus-closed-loop coupling.

PubMed

Sudheer, K Sebastian; Sabir, M

2010-03-01

Recently introduced function projective synchronization in which chaotic systems synchronize up to a scaling function has important applications in secure communications. We design coupling function for unidirectional coupling in identical and mismatched oscillators to realize function projective synchronization through open-plus-closed-loop coupling method. Numerical simulations on Lorenz system, Rossler system, hyperchaotic Lorenz, and hyperchaotic Chen system are presented to verify the effectiveness of the proposed scheme.

Carrier phase synchronization system for improved amplitude modulation and television broadcast reception

DOEpatents

Smith, Stephen F [Loudon, TN; Moore, James A [Powell, TN

2011-02-01

Systems and methods are described for carrier phase synchronization for improved AM and TV broadcast reception. A method includes synchronizing the phase of a carrier frequency of a broadcast signal with the phase of a remote reference frequency. An apparatus includes a receiver to detect the phase of a reference signal; a phase comparator coupled to the reference signal-phase receiver; a voltage controlled oscillator coupled to the phase comparator; and a phase-controlled radio frequency output coupled to the voltage controlled oscillator.

Word and frame synchronization with verification for PPM optical communications

NASA Technical Reports Server (NTRS)

Marshall, William K.

1986-01-01

A method for obtaining word and frame synchronization in pulse position modulated optical communication systems is described. The method uses a short sync sequence inserted at the beginning of each data frame and a verification procedure to distinguish between inserted and randomly occurring sequences at the receiver. This results in an easy to implement sync system which provides reliable synchronization even at high symbol error rates. Results are given for the application of this approach to a highly energy efficient 256-ary PPM test system.

Methods, systems and apparatus for synchronous current regulation of a five-phase machine

DOEpatents

Gallegos-Lopez, Gabriel; Perisic, Milun

2012-10-09

Methods, systems and apparatus are provided for controlling operation of and regulating current provided to a five-phase machine when one or more phases has experienced a fault or has failed. In one implementation, the disclosed embodiments can be used to synchronously regulate current in a vector controlled motor drive system that includes a five-phase AC machine, a five-phase inverter module coupled to the five-phase AC machine, and a synchronous current regulator.

21 CFR 522.995 - Fluprostenol.

Code of Federal Regulations, 2014 CFR

2014-04-01

... intramuscular injection. (2) Indications for use. For use in mares for its luteolytic effect to control the timing of estrus in estrous cycling and in clinically anestrous mares that have a corpus luteum. (3...

Finite time synchronization of memristor-based Cohen-Grossberg neural networks with mixed delays.

PubMed

Chen, Chuan; Li, Lixiang; Peng, Haipeng; Yang, Yixian

2017-01-01

Finite time synchronization, which means synchronization can be achieved in a settling time, is desirable in some practical applications. However, most of the published results on finite time synchronization don't include delays or only include discrete delays. In view of the fact that distributed delays inevitably exist in neural networks, this paper aims to investigate the finite time synchronization of memristor-based Cohen-Grossberg neural networks (MCGNNs) with both discrete delay and distributed delay (mixed delays). By means of a simple feedback controller and novel finite time synchronization analysis methods, several new criteria are derived to ensure the finite time synchronization of MCGNNs with mixed delays. The obtained criteria are very concise and easy to verify. Numerical simulations are presented to demonstrate the effectiveness of our theoretical results.

Inferring Functional Neural Connectivity with Phase Synchronization Analysis: A Review of Methodology

PubMed Central

Sun, Junfeng; Li, Zhijun; Tong, Shanbao

2012-01-01

Functional neural connectivity is drawing increasing attention in neuroscience research. To infer functional connectivity from observed neural signals, various methods have been proposed. Among them, phase synchronization analysis is an important and effective one which examines the relationship of instantaneous phase between neural signals but neglecting the influence of their amplitudes. In this paper, we review the advances in methodologies of phase synchronization analysis. In particular, we discuss the definitions of instantaneous phase, the indexes of phase synchronization and their significance test, the issues that may affect the detection of phase synchronization and the extensions of phase synchronization analysis. In practice, phase synchronization analysis may be affected by observational noise, insufficient samples of the signals, volume conduction, and reference in recording neural signals. We make comments and suggestions on these issues so as to better apply phase synchronization analysis to inferring functional connectivity from neural signals. PMID:22577470

Effect of variability in lighting and temperature environments for mature gilts housed in gestation crates on measures of reproduction and animal well-being.

PubMed

Canaday, D C; Salak-Johnson, J L; Visconti, A M; Wang, X; Bhalerao, K; Knox, R V

2013-03-01

The effects of room temperature and light intensity before breeding and into early gestation were evaluated on the reproductive performance and well-being of gilts housed individually in crates. In eight replicates, estrus was synchronized in mature gilts (n = 198) and after last feeding of Matrix were randomly assigned to a room temperature of 15°C (COLD), 21°C (NEUTRAL), or 30°C (HOT) and a light intensity of 11 (DIM) or 433 (BRIGHT) lx. Estrous detection was performed daily and gilts inseminated twice. Blood samples were collected before and after breeding for determination of immune measures and cortisol concentrations. Gilt ADFI, BW, and body temperature were measured. On d 30 postbreeding, gilts were slaughtered to recover reproductive tracts to evaluate pregnancy and litter characteristics. There were no temperature × light intensity interactions for any response variable. Reproductive measures of follicle development, expression of estrus, ovulation rate, pregnancy rate (83.2%), litter size (14.3 ± 0.5), and fetal measures were not affected by temperature or lighting (P > 0.10). Gilts in COLD (37.6°C) had a lower (P < 0.05) rectal temperature than those in NEUTRAL (38.2°C) and HOT (38.6 ± 0.04°C). Both BW gain and final BW were greater (P < 0.0001) for gilts kept in HOT than those in NEUTRAL or COLD environments. Cortisol was greater (P < 0.01) for gilts kept in COLD compared with those kept in the HOT room. Gilts housed in the HOT environment made more postural changes (P < 0.05) than did those kept in either COLD or NEUTRAL temperatures. Gilts kept in the HOT temperature spent more total time lying and more time lying ventrally compared with those gilts housed in the NEUTRAL or COLD rooms. Total white blood cells and the percentage of neutrophils as well as neutrophil-to-lymphocyte ratio were all influenced (P < 0.05) by temperature but there was no effect (P > 0.10) of light or interaction with temperature on other immune cells or measures. These results indicate that temperatures in the range of 15 to 30°C or light intensity at 11 to 433 lx do not impact reproduction during the follicular phase and into early gestation for mature gilts housed in gestation crates. However, room temperature does impact physiological, behavioral, and immune responses of mature gilts and should be considered as a potential factor that may influence gilt well-being during the first 30 d postbreeding.

Unified synchronization criteria in an array of coupled neural networks with hybrid impulses.

PubMed

Wang, Nan; Li, Xuechen; Lu, Jianquan; Alsaadi, Fuad E

2018-05-01

This paper investigates the problem of globally exponential synchronization of coupled neural networks with hybrid impulses. Two new concepts on average impulsive interval and average impulsive gain are proposed to deal with the difficulties coming from hybrid impulses. By employing the Lyapunov method combined with some mathematical analysis, some efficient unified criteria are obtained to guarantee the globally exponential synchronization of impulsive networks. Our method and criteria are proved to be effective for impulsively coupled neural networks simultaneously with synchronizing impulses and desynchronizing impulses, and we do not need to discuss these two kinds of impulses separately. Moreover, by using our average impulsive interval method, we can obtain an interesting and valuable result for the case of average impulsive interval T a =∞. For some sparse impulsive sequences with T a =∞, the impulses can happen for infinite number of times, but they do not have essential influence on the synchronization property of networks. Finally, numerical examples including scale-free networks are exploited to illustrate our theoretical results. Copyright © 2018 Elsevier Ltd. All rights reserved.

Unbiased and robust quantification of synchronization between spikes and local field potential.

PubMed

Li, Zhaohui; Cui, Dong; Li, Xiaoli

2016-08-30

In neuroscience, relating the spiking activity of individual neurons to the local field potential (LFP) of neural ensembles is an increasingly useful approach for studying rhythmic neuronal synchronization. Many methods have been proposed to measure the strength of the association between spikes and rhythms in the LFP recordings, and most existing measures are dependent upon the total number of spikes. In the present work, we introduce a robust approach for quantifying spike-LFP synchronization which performs reliably for limited samples of data. The measure is termed as spike-triggered correlation matrix synchronization (SCMS), which takes LFP segments centered on each spike as multi-channel signals and calculates the index of spike-LFP synchronization by constructing a correlation matrix. The simulation based on artificial data shows that the SCMS output almost does not change with the sample size. This property is of crucial importance when making comparisons between different experimental conditions. When applied to actual neuronal data recorded from the monkey primary visual cortex, it is found that the spike-LFP synchronization strength shows orientation selectivity to drifting gratings. In comparison to another unbiased method, pairwise phase consistency (PPC), the proposed SCMS behaves better for noisy spike trains by means of numerical simulations. This study demonstrates the basic idea and calculating process of the SCMS method. Considering its unbiasedness and robustness, the measure is of great advantage to characterize the synchronization between spike trains and rhythms present in LFP. Copyright © 2016 Elsevier B.V. All rights reserved.

An image‐based method to synchronize cone‐beam CT and optical surface tracking

PubMed Central

Schaerer, Joël; Riboldi, Marco; Sarrut, David; Baroni, Guido

2015-01-01

The integration of in‐room X‐ray imaging and optical surface tracking has gained increasing importance in the field of image guided radiotherapy (IGRT). An essential step for this integration consists of temporally synchronizing the acquisition of X‐ray projections and surface data. We present an image‐based method for the synchronization of cone‐beam computed tomography (CBCT) and optical surface systems, which does not require the use of additional hardware. The method is based on optically tracking the motion of a component of the CBCT/gantry unit, which rotates during the acquisition of the CBCT scan. A calibration procedure was implemented to relate the position of the rotating component identified by the optical system with the time elapsed since the beginning of the CBCT scan, thus obtaining the temporal correspondence between the acquisition of X‐ray projections and surface data. The accuracy of the proposed synchronization method was evaluated on a motorized moving phantom, performing eight simultaneous acquisitions with an Elekta Synergy CBCT machine and the AlignRT optical device. The median time difference between the sinusoidal peaks of phantom motion signals extracted from the synchronized CBCT and AlignRT systems ranged between ‐3.1 and 12.9 msec, with a maximum interquartile range of 14.4 msec. The method was also applied to clinical data acquired from seven lung cancer patients, demonstrating the potential of the proposed approach in estimating the individual and daily variations in respiratory parameters and motion correlation of internal and external structures. The presented synchronization method can be particularly useful for tumor tracking applications in extracranial radiation treatments, especially in the field of patient‐specific breathing models, based on the correlation between internal tumor motion and external surface surrogates. PACS number: 87

21 CFR 520.1341 - Megestrol acetate tablets.

Code of Federal Regulations, 2011 CFR

2011-04-01

... the postponement of estrus and the alleviation of false pregnancy. (2) It is administered orally... false pregnancy, 1 milligram per pound of body weight per day for 8 days. (3) Full dosage regimen must...

Ventilatory, metabolic, and thermal responses to hypercapnia in female rats: effects of estrous cycle, ovariectomy, and hormonal replacement.

PubMed

Marques, Danuzia A; de Carvalho, Débora; da Silva, Glauber S F; Szawka, Raphael E; Anselmo-Franci, Janete A; Bícego, Kênia C; Gargaglioni, Luciane H

2015-07-01

The aim of this study was to examine how estrous cycle, ovariectomy, and hormonal replacement affect the respiratory [ventilation (V̇e), tidal volume, and respiratory frequency], metabolic (V̇o2), and thermoregulatory (body temperature) responses to hypercapnia (7% CO2) in female Wistar rats. The parameters were measured in rats during different phases of the estrous cycle, and also in ovariectomized (OVX) rats supplemented with 17β-estradiol (OVX+E2), with a combination of E2 and progesterone (OVX+E2P), or with corn oil (OVX+O, vehicle). All experiments were conducted on day 8 after ovariectomy. The intact animals did not present alterations during normocapnia or under hypercapnia in V̇e, tidal volume, respiratory frequency, V̇o2, and V̇e/V̇o2 in the different phases of the estrous cycle. However, body temperature was higher in female rats on estrus. Hormonal replacement did not change the ventilatory, thermoregulatory, or metabolic parameters during hypercapnia, compared with the OVX animals. Nevertheless, OVX+E2, OVX+E2P, and OVX+O presented lower hypercapnic ventilatory responses compared with intact females on the day of estrus. Also, rats in estrus showed higher V̇e and V̇e/V̇o2 during hypercapnia than OVX animals. The data suggest that other gonadal factors, besides E2 and P, are possibly involved in these responses. Copyright © 2015 the American Physiological Society.

Seizure susceptibility in intact and ovariectomized female rats treated with the convulsant pilocarpine

PubMed Central

Scharfman, Helen E.; Goodman, Jeffrey H.; Rigoulot, Marie-Aude; Berger, Russell E.; Walling, Susan G.; Mercurio, Thomas C.; Stormes, Kerry; Maclusky, Neil J.

2008-01-01

Despite numerous neuroendocrinological studies of seizures, the influence of estrogen and progesterone on seizures and epilepsy remains unclear. This may be due to the fact that previous studies have not systematically compared distinct endocrine conditions and included all relevant controls. The goal of the present study was to conduct such a study using pilocarpine as chemoconvulsant. Thus, age and weight-matched, intact or ovariectomized rats were tested to determine incidence of status epilepticus and to study events leading to status. Intact female rats were sampled at each cycle stage (proestrus, estrus, metestrus, or diestrus 2). Convulsant was administered at the same time of day, 10:00–10:30 a.m. Statistical analysis showed that there was a significantly lower incidence of status on the morning of estrus, but differences were attenuated in older animals. Ovariectomized rats were distinct in their rapid progression to status. These results show that the incidence of status in female rats following pilocarpine injection, and the progression to pilocarpine-induced status, are influenced by reproductive state as well as age. The hormonal milieu present specifically on the morning of estrus appears to decrease susceptibility to pilocarpine-induced status, particularly at young ages. In contrast, the chronic absence of reproductive steroids that characterizes the ovariectomized rat leads to a more rapid progression to status. This dissociation between incidence vs. progression provides new insight into the influence of estrogen and progesterone on seizures. PMID:16084511

Synthesis and evaluation of phase detectors for active bit synchronizers

NASA Technical Reports Server (NTRS)

Mcbride, A. L.

1974-01-01

Self-synchronizing digital data communication systems usually use active or phase-locked loop (PLL) bit synchronizers. The three main elements of PLL synchronizers are the phase detector, loop filter, and the voltage controlled oscillator. Of these three elements, phase detector synthesis is the main source of difficulty, particularly when the received signals are demodulated square-wave signals. A phase detector synthesis technique is reviewed that provides a physically realizable design for bit synchronizer phase detectors. The development is based upon nonlinear recursive estimation methods. The phase detector portion of the algorithm is isolated and analyzed.

Analysis of the time structure of synchronization in multidimensional chaotic systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makarenko, A. V., E-mail: avm.science@mail.ru

2015-05-15

A new approach is proposed to the integrated analysis of the time structure of synchronization of multidimensional chaotic systems. The method allows one to diagnose and quantitatively evaluate the intermittency characteristics during synchronization of chaotic oscillations in the T-synchronization mode. A system of two identical logistic mappings with unidirectional coupling that operate in the developed chaos regime is analyzed. It is shown that the widely used approach, in which only synchronization patterns are subjected to analysis while desynchronization areas are considered as a background signal and removed from analysis, should be regarded as methodologically incomplete.

Luteal function, largest follicle, and fertility in postpartum dairy cows treated with 14dCIDR-PGF2α versus 2xPGF2α-Ovsynch for timed AI.

PubMed

Escalante, Rebecca C; Poock, Scott E; Lucy, Matthew C

2013-11-01

A method for timed artificial insemination (AI) that is used for beef cows, beef heifers, and dairy heifers employs progesterone-releasing inserts, such as the controlled internal drug release (CIDR; Zoetis, New York, NY, USA) that are left in place for 14 days. The 14-day CIDR treatment is a method of presynchronization that ensures that cattle are in the late luteal phase of the estrous cycle when PGF2α is administered before timed AI. The objective of this study was to test the effectiveness of the 14dCIDR-PGF2α program in postpartum dairy cows by comparing it with the traditional "Presynch-Ovsynch" (2xPGF2α-Ovsynch) program. The 14dCIDR-PGF2α cows (n = 132) were treated with a CIDR insert on Day 0 for 14 days. At 19 days after CIDR removal (Day 33), the cows were treated with a luteolytic dose of PGF2α, 56 hours later were treated with an ovulatory dose of GnRH (Day 35), and 16 hours later were inseminated. The 2xPGF2α-Ovsynch cows were treated with a luteolytic dose of PGF2α on Day 0 and again on Day 14. At 12 days after the second PGF2α treatment (Day 26), the cows were treated with GnRH. At 7 days after GnRH, the cows were treated with PGF2α (Day 33), then 56 hours later treated with GnRH (Day 35), and then 16 hours later were inseminated. There was no effect of treatment or treatment by parity interaction on pregnancies per AI (P/AI) when pregnancy diagnosis was performed on Day 32 (115/263; 43.7%) or Days 60 to 90 (99/263; 37.6%) after insemination. There was an effect of parity (P < 0.05) on P/AI because primiparous cows had lesser P/AI (35/98; 35.7%) than multiparous cows (80/165; 48.5%) on Day 32. Cows observed in estrus after the presynchronization step (within 5 days after CIDR removal or within 5 days after the second PGF2α treatment) had greater P/AI than those not observed in estrus (55/103; 53.4% vs. 60/160; 37.5%; observed vs. not observed; P < 0.01; d 32 pregnancy diagnosis). When progesterone data were examined in a subset of cows (n = 208), 55.3% of cows had a "prototypical" response to treatment (i.e., the cow had an estrous cycle that was synchronized by the presynchronization treatment and then the cow responded appropriately to the subsequent PGF2α and GnRH treatments before timed AI). Collectively, cows with a prototypical response to either treatment had 52.2% P/AI that was greater (P < 0.001) than the P/AI for cows that had a nonprototypical response (19%) (P/AI determined at 60-90 days of pregnancy). In conclusion, we did not detect a difference in P/AI when postpartum dairy cows were treated with 14dCIDR-PGF2α or 2xPGF2α-Ovsynch before timed AI. The primary limitation to the success of either program was the failure of the cow to respond appropriately to the sequence of treatments. Copyright © 2013 Elsevier Inc. All rights reserved.

Desynchronization of stochastically synchronized chemical oscillators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Snari, Razan; Tinsley, Mark R., E-mail: mark.tinsley@mail.wvu.edu, E-mail: kshowalt@wvu.edu; Faramarzi, Sadegh

Experimental and theoretical studies are presented on the design of perturbations that enhance desynchronization in populations of oscillators that are synchronized by periodic entrainment. A phase reduction approach is used to determine optimal perturbation timing based upon experimentally measured phase response curves. The effectiveness of the perturbation waveforms is tested experimentally in populations of periodically and stochastically synchronized chemical oscillators. The relevance of the approach to therapeutic methods for disrupting phase coherence in groups of stochastically synchronized neuronal oscillators is discussed.

Scanning Synchronization of Colliding Bunches for MEIC Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Derbenev, Yaroslav S.; Popov, V. P.; Chernousov, Yu D.

2015-09-01

Synchronization of colliding beams is one of the major issues of an electron-ion collider (EIC) design because of sensitivity of ion revolution frequency to beam energy. A conventional solution for this trouble is insertion of bent chicanes in the arcs space. In our report we consider a method to provide space coincidence of encountering bunches in the crab-crossing orbits Interaction Region (IR) while repetition rates of two beams do not coincide. The method utilizes pair of fast kickers realizing a bypass for the electron bunches as the way to equalize positions of the colliding bunches at the Interaction Point (IP).more » A dipole-mode warm or SRF cavities fed by the magnetron transmitters are used as fast kickers, allowing a broad-band phase and amplitude control. The proposed scanning synchronization method implies stabilization of luminosity at a maximum via a feedback loop. This synchronization method is evaluated as perspective for the Medium Energy Electron-Ion collider (MEIC) project of JLab with its very high bunch repetition rate.« less

Clustering PPI data by combining FA and SHC method.

PubMed

Lei, Xiujuan; Ying, Chao; Wu, Fang-Xiang; Xu, Jin

2015-01-01

Clustering is one of main methods to identify functional modules from protein-protein interaction (PPI) data. Nevertheless traditional clustering methods may not be effective for clustering PPI data. In this paper, we proposed a novel method for clustering PPI data by combining firefly algorithm (FA) and synchronization-based hierarchical clustering (SHC) algorithm. Firstly, the PPI data are preprocessed via spectral clustering (SC) which transforms the high-dimensional similarity matrix into a low dimension matrix. Then the SHC algorithm is used to perform clustering. In SHC algorithm, hierarchical clustering is achieved by enlarging the neighborhood radius of synchronized objects continuously, while the hierarchical search is very difficult to find the optimal neighborhood radius of synchronization and the efficiency is not high. So we adopt the firefly algorithm to determine the optimal threshold of the neighborhood radius of synchronization automatically. The proposed algorithm is tested on the MIPS PPI dataset. The results show that our proposed algorithm is better than the traditional algorithms in precision, recall and f-measure value.

Clustering PPI data by combining FA and SHC method

PubMed Central

2015-01-01

Clustering is one of main methods to identify functional modules from protein-protein interaction (PPI) data. Nevertheless traditional clustering methods may not be effective for clustering PPI data. In this paper, we proposed a novel method for clustering PPI data by combining firefly algorithm (FA) and synchronization-based hierarchical clustering (SHC) algorithm. Firstly, the PPI data are preprocessed via spectral clustering (SC) which transforms the high-dimensional similarity matrix into a low dimension matrix. Then the SHC algorithm is used to perform clustering. In SHC algorithm, hierarchical clustering is achieved by enlarging the neighborhood radius of synchronized objects continuously, while the hierarchical search is very difficult to find the optimal neighborhood radius of synchronization and the efficiency is not high. So we adopt the firefly algorithm to determine the optimal threshold of the neighborhood radius of synchronization automatically. The proposed algorithm is tested on the MIPS PPI dataset. The results show that our proposed algorithm is better than the traditional algorithms in precision, recall and f-measure value. PMID:25707632

The Role of Synchronous Virtual Reference in Teaching and Learning: A Grounded Theory Analysis of Instant Messaging Transcripts

ERIC Educational Resources Information Center

Passonneau, Sarah; Coffey, Dan

2011-01-01

Electronic communication technologies continue to change the landscape of reference services. For many users, virtual communication is the preferred means of conversing. Synchronous virtual reference, similar to other synchronous means of communication, is an important method for reaching students and for providing teaching and learning…

Projective-anticipating, projective, and projective-lag synchronization of time-delayed chaotic systems on random networks.

PubMed

Feng, Cun-Fang; Xu, Xin-Jian; Wang, Sheng-Jun; Wang, Ying-Hai

2008-06-01

We study projective-anticipating, projective, and projective-lag synchronization of time-delayed chaotic systems on random networks. We relax some limitations of previous work, where projective-anticipating and projective-lag synchronization can be achieved only on two coupled chaotic systems. In this paper, we realize projective-anticipating and projective-lag synchronization on complex dynamical networks composed of a large number of interconnected components. At the same time, although previous work studied projective synchronization on complex dynamical networks, the dynamics of the nodes are coupled partially linear chaotic systems. In this paper, the dynamics of the nodes of the complex networks are time-delayed chaotic systems without the limitation of the partial linearity. Based on the Lyapunov stability theory, we suggest a generic method to achieve the projective-anticipating, projective, and projective-lag synchronization of time-delayed chaotic systems on random dynamical networks, and we find both its existence and sufficient stability conditions. The validity of the proposed method is demonstrated and verified by examining specific examples using Ikeda and Mackey-Glass systems on Erdos-Renyi networks.

Plasma progesterone profiles, ovulation rate, donor embryo yield and recipient embryo survival in native Saloia sheep in the fall and spring breeding seasons.

PubMed

Chagas e Silva, J; Lopes da Costa, L; Cidadão, R; Robalo Silva, J

2003-08-01

The response to superovulatory (SOV) and estrus synchronization (ES) treatments and the fertility of donor (n=68) and recipient (n=118) Saloia ewes was evaluated in the fall and spring breeding seasons. The proportion of acyclic ewes at treatment time was significantly higher in the spring than in the fall (42.6% versus 4.0%, P<0.00001). Donors treated with eCG had a significantly higher mean number of follicles over 5mm in diameter in the ovaries at embryo recovery and a significantly lower mean efficiency of recovery than FSH-treated ewes. These negative effects were more pronounced in the fall than in the spring, which resulted in a significantly lower mean number of total and fertilized ova recovered from eCG-treated ewes, compared to FSH donors in the fall, but not in the spring. Season had no significant effect on the ovulation rate and plasma P4 concentrations of recipients treated with a progestagen plus eCG combination. Although the recipient lambing and embryo survival rates were higher in the fall than in the spring the differences were not significant. No significant differences were observed in the ovulation rate or P4 concentrations of recipients that lambed compared to those that did not lamb. These preliminary results show that, in Portugal, response of Saloia ewes to SOV or ES treatments and donor fertility following the SOV treatment were similar in the spring and the fall, which suggests that in the spring acyclic ewes are in moderate anestrus. The effect of season on fertility following embryo transfer should be confirmed in further studies involving a larger number of animals. The semilaparoscopic transfer method reported here allowed lambing and embryo survival rates higher (although not significantly) than a standard surgical approach.

A Mathematical Model for Storage and Recall of Images using Targeted Synchronization of Coupled Maps.

PubMed

Palaniyandi, P; Rangarajan, Govindan

2017-08-21

We propose a mathematical model for storage and recall of images using coupled maps. We start by theoretically investigating targeted synchronization in coupled map systems wherein only a desired (partial) subset of the maps is made to synchronize. A simple method is introduced to specify coupling coefficients such that targeted synchronization is ensured. The principle of this method is extended to storage/recall of images using coupled Rulkov maps. The process of adjusting coupling coefficients between Rulkov maps (often used to model neurons) for the purpose of storing a desired image mimics the process of adjusting synaptic strengths between neurons to store memories. Our method uses both synchronisation and synaptic weight modification, as the human brain is thought to do. The stored image can be recalled by providing an initial random pattern to the dynamical system. The storage and recall of the standard image of Lena is explicitly demonstrated.

Parallel discrete-event simulation of FCFS stochastic queueing networks

NASA Technical Reports Server (NTRS)

Nicol, David M.

1988-01-01

Physical systems are inherently parallel. Intuition suggests that simulations of these systems may be amenable to parallel execution. The parallel execution of a discrete-event simulation requires careful synchronization of processes in order to ensure the execution's correctness; this synchronization can degrade performance. Largely negative results were recently reported in a study which used a well-known synchronization method on queueing network simulations. Discussed here is a synchronization method (appointments), which has proven itself to be effective on simulations of FCFS queueing networks. The key concept behind appointments is the provision of lookahead. Lookahead is a prediction on a processor's future behavior, based on an analysis of the processor's simulation state. It is shown how lookahead can be computed for FCFS queueing network simulations, give performance data that demonstrates the method's effectiveness under moderate to heavy loads, and discuss performance tradeoffs between the quality of lookahead, and the cost of computing lookahead.

Regression analysis of sparse asynchronous longitudinal data.

PubMed

Cao, Hongyuan; Zeng, Donglin; Fine, Jason P

2015-09-01

We consider estimation of regression models for sparse asynchronous longitudinal observations, where time-dependent responses and covariates are observed intermittently within subjects. Unlike with synchronous data, where the response and covariates are observed at the same time point, with asynchronous data, the observation times are mismatched. Simple kernel-weighted estimating equations are proposed for generalized linear models with either time invariant or time-dependent coefficients under smoothness assumptions for the covariate processes which are similar to those for synchronous data. For models with either time invariant or time-dependent coefficients, the estimators are consistent and asymptotically normal but converge at slower rates than those achieved with synchronous data. Simulation studies evidence that the methods perform well with realistic sample sizes and may be superior to a naive application of methods for synchronous data based on an ad hoc last value carried forward approach. The practical utility of the methods is illustrated on data from a study on human immunodeficiency virus.

Self-stabilizing byzantine-fault-tolerant clock synchronization system and method

NASA Technical Reports Server (NTRS)

Malekpour, Mahyar R. (Inventor)

2012-01-01

Systems and methods for rapid Byzantine-fault-tolerant self-stabilizing clock synchronization are provided. The systems and methods are based on a protocol comprising a state machine and a set of monitors that execute once every local oscillator tick. The protocol is independent of specific application specific requirements. The faults are assumed to be arbitrary and/or malicious. All timing measures of variables are based on the node's local clock and thus no central clock or externally generated pulse is used. Instances of the protocol are shown to tolerate bursts of transient failures and deterministically converge with a linear convergence time with respect to the synchronization period as predicted.

Neural network analysis of electrodynamic activity of yeast cells around 1 kHz

NASA Astrophysics Data System (ADS)

Janca, R.

2011-12-01

This paper deals with data analysis of electrodynamic activity of two mutants of yeast cells, cell cycle of which is synchronized and non-synchronized, respectively. We used data already published by Jelinek et al. and treat them with data mining method based on the multilayer neural network. Intersection of data mining and statistical distribution of the noise shows significant difference between synchronized and non-synchronized yeasts not only in total power, but also discrete frequencies.

[Cardiac Synchronization Function Estimation Based on ASM Level Set Segmentation Method].

PubMed

Zhang, Yaonan; Gao, Yuan; Tang, Liang; He, Ying; Zhang, Huie

At present, there is no accurate and quantitative methods for the determination of cardiac mechanical synchronism, and quantitative determination of the synchronization function of the four cardiac cavities with medical images has a great clinical value. This paper uses the whole heart ultrasound image sequence, and segments the left & right atriums and left & right ventricles of each frame. After the segmentation, the number of pixels in each cavity and in each frame is recorded, and the areas of the four cavities of the image sequence are therefore obtained. The area change curves of the four cavities are further extracted, and the synchronous information of the four cavities is obtained. Because of the low SNR of Ultrasound images, the boundary lines of cardiac cavities are vague, so the extraction of cardiac contours is still a challenging problem. Therefore, the ASM model information is added to the traditional level set method to force the curve evolution process. According to the experimental results, the improved method improves the accuracy of the segmentation. Furthermore, based on the ventricular segmentation, the right and left ventricular systolic functions are evaluated, mainly according to the area changes. The synchronization of the four cavities of the heart is estimated based on the area changes and the volume changes.

Suppression of anomalous synchronization and nonstationary behavior of neural network under small-world topology

NASA Astrophysics Data System (ADS)

Boaretto, B. R. R.; Budzinski, R. C.; Prado, T. L.; Kurths, J.; Lopes, S. R.

2018-05-01

It is known that neural networks under small-world topology can present anomalous synchronization and nonstationary behavior for weak coupling regimes. Here, we propose methods to suppress the anomalous synchronization and also to diminish the nonstationary behavior occurring in weakly coupled neural network under small-world topology. We consider a network of 2000 thermally sensitive identical neurons, based on the model of Hodgkin-Huxley in a small-world topology, with the probability of adding non local connection equal to p = 0 . 001. Based on experimental protocols to suppress anomalous synchronization, as well as nonstationary behavior of the neural network dynamics, we make use of (i) external stimulus (pulsed current); (ii) biologic parameters changing (neuron membrane conductance changes); and (iii) body temperature changes. Quantification analysis to evaluate phase synchronization makes use of the Kuramoto's order parameter, while recurrence quantification analysis, particularly the determinism, computed over the easily accessible mean field of network, the local field potential (LFP), is used to evaluate nonstationary states. We show that the methods proposed can control the anomalous synchronization and nonstationarity occurring for weak coupling parameter without any effect on the individual neuron dynamics, neither in the expected asymptotic synchronized states occurring for large values of the coupling parameter.

Collaborative voxel-based surgical virtual environments.

PubMed

Acosta, Eric; Muniz, Gilbert; Armonda, Rocco; Bowyer, Mark; Liu, Alan

2008-01-01

Virtual Reality-based surgical simulators can utilize Collaborative Virtual Environments (C-VEs) to provide team-based training. To support real-time interactions, C-VEs are typically replicated on each user's local computer and a synchronization method helps keep all local copies consistent. This approach does not work well for voxel-based C-VEs since large and frequent volumetric updates make synchronization difficult. This paper describes a method that allows multiple users to interact within a voxel-based C-VE for a craniotomy simulator being developed. Our C-VE method requires smaller update sizes and provides faster synchronization update rates than volumetric-based methods. Additionally, we address network bandwidth/latency issues to simulate networked haptic and bone drilling tool interactions with a voxel-based skull C-VE.

Global synchronization in finite time for fractional-order neural networks with discontinuous activations and time delays.

PubMed

Peng, Xiao; Wu, Huaiqin; Song, Ka; Shi, Jiaxin

2017-10-01

This paper is concerned with the global Mittag-Leffler synchronization and the synchronization in finite time for fractional-order neural networks (FNNs) with discontinuous activations and time delays. Firstly, the properties with respect to Mittag-Leffler convergence and convergence in finite time, which play a critical role in the investigation of the global synchronization of FNNs, are developed, respectively. Secondly, the novel state-feedback controller, which includes time delays and discontinuous factors, is designed to realize the synchronization goal. By applying the fractional differential inclusion theory, inequality analysis technique and the proposed convergence properties, the sufficient conditions to achieve the global Mittag-Leffler synchronization and the synchronization in finite time are addressed in terms of linear matrix inequalities (LMIs). In addition, the upper bound of the setting time of the global synchronization in finite time is explicitly evaluated. Finally, two examples are given to demonstrate the validity of the proposed design method and theoretical results. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of human chorionic gonadotropin on luteal function and reproductive performance of high-producing lactating Holstein dairy cows.

PubMed

Santos, J E; Thatcher, W W; Pool, L; Overton, M W

2001-11-01

The objectives were to evaluate effects of human chorionic gonadotropin (hCG) (3,300 IU i.m.) administered on d 5 after AI on CL number, plasma progesterone concentration, conception rate, and pregnancy loss in high-producing dairy cows. Following the synchronization of estrus and AI, 406 cows were injected with either hCG or saline on d 5 after AI in a randomized complete block design. Blood sampling and ovarian ultrasonography were conducted once between d 11 and 16 after AI. Pregnancy diagnoses were performed on d 28 by ultrasonography and on d 45 and 90 after AI by rectal palpation. Treatment with hCG on d 5 resulted in 86.2% of the cows with more than one CL compared with 23.2% in controls. Plasma progesterone concentrations were increased by 5.0 ng/mL in hCG-treated cows. The presence of more than one CL increased progesterone concentration in hCG-treated cows but not in controls. Conception rates were higher for hCG-treated cows on d 28 (45.8 > 38.7%), 45 (40.4 > 36.3%), and 90 (38.4 > 31.9%) after AI. Treatment with hCG improved conception rate in cows losing body condition between AI and d 28 after Al. Pregnancy losses were similar between treatment groups. Treatment with hCG on d 5 after AI induces accessory CL, enhances plasma progesterone concentration, and improves conception rate of high-producing dairy cows.

Birth seasonality and pattern in black-and-white snub-nosed monkeys (Rhinopithecus bieti) at Mt. Lasha, Yunnan.

PubMed

Li, Jin-Fa; He, Yu-Chao; Huang, Zhi-Pang; Wang, Shuang-Jin; Xiang, Zuo-Fu; Zhao, Juan-Jun; Xiao, Wen; Cui, Liang-Wei

2014-11-18

Seasonal variation in environmental factors is vital to the regulation of seasonal reproduction in primates. Consequently, long-term systematic data is necessary to clarify the birth seasonality and pattern of primates in highly seasonal environments. This study indicated that black-and-white snub-nosed monkeys (Rhinopithecus bieti) at Mt. Lasha exhibited strict birth seasonality with a pulse model. Infants were born with a certain degree of synchronization. Birth distribution showed three birth peaks, and the birth pattern showed a "V" style in even-numbered years and a gradual increase in odd-numbered years. The beginning date, end date and median birth date were earlier in even-numbered years than those in odd-numbered years. The higher latitude of their habitats, earlier birth date, shorter birth period, fewer birth peaks and stronger birth synchrony might be adaptations for strongly seasonal variation in climate and food resources. After the summer solstice when daylight length began to gradually shorten, R. bieti at Mt. Lasha started to breed during the period with the highest environmental temperature and food availability, which implied that photoperiod may be the proximate factor triggering the onset of estrus and mating. It appears that R. bieti coincided conception and mid-lactation with the peak in staple foods, and weaning with the peak in high quality of foods. Thus, food availability was the ultimate factor regulating reproductive seasonality, and photoperiod was the proximate factor fine-turning the coordination between seasonal breeding and food availability.

O(t-α)-synchronization and Mittag-Leffler synchronization for the fractional-order memristive neural networks with delays and discontinuous neuron activations.

PubMed

Chen, Jiejie; Chen, Boshan; Zeng, Zhigang

2018-04-01

This paper investigates O(t -α )-synchronization and adaptive Mittag-Leffler synchronization for the fractional-order memristive neural networks with delays and discontinuous neuron activations. Firstly, based on the framework of Filippov solution and differential inclusion theory, using a Razumikhin-type method, some sufficient conditions ensuring the global O(t -α )-synchronization of considered networks are established via a linear-type discontinuous control. Next, a new fractional differential inequality is established and two new discontinuous adaptive controller is designed to achieve Mittag-Leffler synchronization between the drive system and the response systems using this inequality. Finally, two numerical simulations are given to show the effectiveness of the theoretical results. Our approach and theoretical results have a leading significance in the design of synchronized fractional-order memristive neural networks circuits involving discontinuous activations and time-varying delays. Copyright © 2018 Elsevier Ltd. All rights reserved.

Neurotransmitter alteration in a testosterone propionate-induced polycystic ovarian syndrome rat model.

PubMed

Chaudhari, Nirja K; Nampoothiri, Laxmipriya P

2017-02-01

Polycystic ovarian syndrome (PCOS), one of the leading causes of infertility seen in women, is characterized by anovulation and hyperandrogenism, resulting in ovarian dysfunction. In addition, associations of several metabolic complications like insulin resistance, obesity, dyslipidemia and psychological co-morbidities are well known in PCOS. One of the major factors influencing mood and the emotional state of mind is neurotransmitters. Also, these neurotransmitters are very crucial for GnRH release. Hence, the current study investigates the status of neurotransmitters in PCOS. A PCOS rat model was developed using testosterone. Twenty-one-day-old rats were subcutaneously injected with 10 mg/kg body weight of testosterone propionate (TP) for 35 days. The animals were validated for PCOS characteristics by monitoring estrus cyclicity, serum testosterone and estradiol levels and by histological examination of ovarian sections. Neurotransmitter estimation was carried out using fluorometric and spectrophotometric methods. TP-treated animals demonstrated increased serum testosterone levels with unaltered estradiol content, disturbed estrus cyclicity and many peripheral cysts in the ovary compared to control rats mimicking human PCOS. Norepinephrine (NE), dopamine, serotonin, γ-amino butyric acid (GABA) and epinephrine levels were significantly low in TP-induced PCOS rats compared to control ones, whereas the activity of acetylcholinesterase in the PCOS brain was markedly elevated. Neurotransmitter alteration could be one of the reasons for disturbed gonadotropin-releasing hormone (GnRH) release, consequently directing the ovarian dysfunction in PCOS. Also, decrease in neurotransmitters, mainly NE, serotonin and dopamine (DA) attributes to mood disorders like depression and anxiety in PCOS.

Artificial insemination in pigs today.

PubMed

Knox, R V

2016-01-01

Use of artificial insemination (AI) for breeding pigs has been instrumental for facilitating global improvements in fertility, genetics, labor, and herd health. The establishment of AI centers for management of boars and production of semen has allowed for selection of boars for fertility and sperm production using in vitro and in vivo measures. Today, boars can be managed for production of 20 to 40 traditional AI doses containing 2.5 to 3.0 billion motile sperm in 75 to 100 mL of extender or 40 to 60 doses with 1.5 to 2.0 billion sperm in similar or reduced volumes for use in cervical or intrauterine AI. Regardless of the sperm dose, in liquid form, extenders are designed to sustain sperm fertility for 3 to 7 days. On farm, AI is the predominant form for commercial sow breeding and relies on manual detection of estrus with sows receiving two cervical or two intrauterine inseminations of the traditional or low sperm doses on each day detected in standing estrus. New approaches for increasing rates of genetic improvement through use of AI are aimed at methods to continue to lower the number of sperm in an AI dose and reducing the number of inseminations through use of a single, fixed-time AI after ovulation induction. Both approaches allow greater selection pressure for economically important swine traits in the sires and help extend the genetic advantages through AI on to more production farms. Copyright © 2016 Elsevier Inc. All rights reserved.

An integrated system for synchronous culture of animal cells under controlled conditions.

PubMed

Mendoza-Pérez, Elena; Hernández, Vanessa; Palomares, Laura A; Serrato, José A

2016-01-01

The cell cycle has fundamental effects on cell cultures and their products. Tools to synchronize cultured cells allow the study of cellular physiology and metabolism at particular cell cycle phases. However, cells are most often arrested by methods that alter their homeostasis and are then cultivated in poorly controlled environments. Cell behavior could then be affected by the synchronization method and culture conditions used, and not just by the particular cell cycle phase under study. Moreover, only a few viable cells are recovered. Here, we designed an integrated system where a large number of cells from a controlled bioreactor culture is separated by centrifugal elutriation at high viabilities. In contrast to current elutriation methods, cells are injected directly from a bioreactor into an injection loop, allowing the introduction of a large number of cells into the separation chamber without stressful centrifugation. A low pulsation peristaltic pump increases the stability of the elutriation chamber. Using this approach, a large number of healthy cells at each cell cycle phase were obtained, allowing their direct inoculation into fully instrumented bioreactors. Hybridoma cells synchronized and cultured in this system behaved as expected for a synchronous culture.

Method and apparatus to debug an integrated circuit chip via synchronous clock stop and scan

DOEpatents

Bellofatto, Ralph E [Ridgefield, CT; Ellavsky, Matthew R [Rochester, MN; Gara, Alan G [Mount Kisco, NY; Giampapa, Mark E [Irvington, NY; Gooding, Thomas M [Rochester, MN; Haring, Rudolf A [Cortlandt Manor, NY; Hehenberger, Lance G [Leander, TX; Ohmacht, Martin [Yorktown Heights, NY

2012-03-20

An apparatus and method for evaluating a state of an electronic or integrated circuit (IC), each IC including one or more processor elements for controlling operations of IC sub-units, and each the IC supporting multiple frequency clock domains. The method comprises: generating a synchronized set of enable signals in correspondence with one or more IC sub-units for starting operation of one or more IC sub-units according to a determined timing configuration; counting, in response to one signal of the synchronized set of enable signals, a number of main processor IC clock cycles; and, upon attaining a desired clock cycle number, generating a stop signal for each unique frequency clock domain to synchronously stop a functional clock for each respective frequency clock domain; and, upon synchronously stopping all on-chip functional clocks on all frequency clock domains in a deterministic fashion, scanning out data values at a desired IC chip state. The apparatus and methodology enables construction of a cycle-by-cycle view of any part of the state of a running IC chip, using a combination of on-chip circuitry and software.

A rare case of uterine adenomyosis in a Siamese cat.

PubMed

Bulman-Fleming, Julie

2008-07-01

A 12-year-old, female Siamese cat with a long-term history of megestrol acetate treatment for suppression of estrus was presented with vomiting and abdominal pain. Uterine adenomyosis was diagnosed after an ovariohysterectomy.

Midterm Stability Evaluation of Wide-area Power System by using Synchronized Phasor Measurements

NASA Astrophysics Data System (ADS)

Ota, Yutaka; Ukai, Hiroyuki; Nakamura, Koichi; Fujita, Hideki

In recent years, the PMU (Phasor Measurement Unit) receives a great deal of attention as a synchronized measurement system of power systems. Synchronized phasor angles obtained by the PMU provide the effective information for evaluating the stability of a bulk power system. The aspect of instability phenomena during midterm tends to be more complicated, and the stability analysis using the synchronized phasor measurements is significant in order to keep a complicated power system stable. This paper proposes a midterm stability evaluation method of the wide-area power system by using the synchronized phasor measurements. By clustering and aggregating the power system to some coherent groups, the step-out is effectively predicted on the basis of the two-machine equivalent power system model. The midterm stability of a longitudinal power system model of Japanese 60Hz systems constructed by the PSA, which is a hybrid-type power system simulator, is practically evaluated using the proposed method.

Designing torus-doubling solutions to discrete time systems by hybrid projective synchronization

NASA Astrophysics Data System (ADS)

Xie, Hui; Wen, Guilin

2013-11-01

Doubling of torus occurs in high dimensional nonlinear systems, which is related to a certain kind of typical second bifurcations. It is a nontrivial task to create a torus-doubling solution with desired dynamical properties based on the classical bifurcation theories. In this paper, dead-beat hybrid projective synchronization is employed to build a novel method for designing stable torus-doubling solutions into discrete time systems with proper properties to achieve the purpose of utilizing bifurcation solutions as well as avoiding the possible conflict of physical meaning of the created solution. Although anti-controls of bifurcation and chaos synchronizations are two different topics in nonlinear dynamics and control, the results imply that it is possible to develop some new interdisciplinary methods between chaos synchronization and anti-controls of bifurcations.

Parallel-aware, dedicated job co-scheduling within/across symmetric multiprocessing nodes

DOEpatents

Jones, Terry R.; Watson, Pythagoras C.; Tuel, William; Brenner, Larry; ,Caffrey, Patrick; Fier, Jeffrey

2010-10-05

In a parallel computing environment comprising a network of SMP nodes each having at least one processor, a parallel-aware co-scheduling method and system for improving the performance and scalability of a dedicated parallel job having synchronizing collective operations. The method and system uses a global co-scheduler and an operating system kernel dispatcher adapted to coordinate interfering system and daemon activities on a node and across nodes to promote intra-node and inter-node overlap of said interfering system and daemon activities as well as intra-node and inter-node overlap of said synchronizing collective operations. In this manner, the impact of random short-lived interruptions, such as timer-decrement processing and periodic daemon activity, on synchronizing collective operations is minimized on large processor-count SPMD bulk-synchronous programming styles.

Synchronization in networks with heterogeneous coupling delays

NASA Astrophysics Data System (ADS)

Otto, Andreas; Radons, Günter; Bachrathy, Dániel; Orosz, Gábor

2018-01-01

Synchronization in networks of identical oscillators with heterogeneous coupling delays is studied. A decomposition of the network dynamics is obtained by block diagonalizing a newly introduced adjacency lag operator which contains the topology of the network as well as the corresponding coupling delays. This generalizes the master stability function approach, which was developed for homogenous delays. As a result the network dynamics can be analyzed by delay differential equations with distributed delay, where different delay distributions emerge for different network modes. Frequency domain methods are used for the stability analysis of synchronized equilibria and synchronized periodic orbits. As an example, the synchronization behavior in a system of delay-coupled Hodgkin-Huxley neurons is investigated. It is shown that the parameter regions where synchronized periodic spiking is unstable expand when increasing the delay heterogeneity.

Power-rate synchronization of coupled genetic oscillators with unbounded time-varying delay.

PubMed

Alofi, Abdulaziz; Ren, Fengli; Al-Mazrooei, Abdullah; Elaiw, Ahmed; Cao, Jinde

2015-10-01

In this paper, a new synchronization problem for the collective dynamics among genetic oscillators with unbounded time-varying delay is investigated. The dynamical system under consideration consists of an array of linearly coupled identical genetic oscillators with each oscillators having unbounded time-delays. A new concept called power-rate synchronization, which is different from both the asymptotical synchronization and the exponential synchronization, is put forward to facilitate handling the unbounded time-varying delays. By using a combination of the Lyapunov functional method, matrix inequality techniques and properties of Kronecker product, we derive several sufficient conditions that ensure the coupled genetic oscillators to be power-rate synchronized. The criteria obtained in this paper are in the form of matrix inequalities. Illustrative example is presented to show the effectiveness of the obtained results.

Results of continuous synchronous orbit testing of sealed nickel-cadmium cells

NASA Technical Reports Server (NTRS)

Harkness, J. D.

1981-01-01

Test results from continuous synchronous orbit testing of sealed nickel cadmium cells are presented. The synchronous orbit regime simulates a space satellite maintaining a position over a fixed point on earth as the earth rotates on its axis and revolves about the sun. Characteristics of each lot of cells, test conditions, and charge control methods are described.

Comparison between male and female rats in a model of self-administration of a chocolate-flavored beverage: Behavioral and neurochemical studies.

PubMed

Contini, Andrea; Sanna, Fabrizio; Maccioni, Paola; Colombo, Giancarlo; Argiolas, Antonio

2018-05-15

The existence of sex differences was studied in a rat model of operant self-administration of a chocolate-flavored beverage (CFB), which possesses strong reinforcing properties and is avidly consumed by rats. Whether these differences occurred concomitantly to changes in extracellular dopamine in the dialysate obtained from the nucleus accumbens, was assessed by intracerebral microdialysis. Male, ovariectomized and intact female rats showed similar self-administration profiles, with minor differences in both acquisition and maintenance phases. Intact females self-administered larger amounts of CFB, when expressed per body weight, than males and ovariectomized females, in spite of similar values of lever-responding, latency to the first lever-response and consumption efficiency (a measure of rat's licking effectiveness) in males, ovariectomized and intact females and no difference in breakpoint value and number of lever-responses emerged when males, ovariectomized and intact females were exposed to a progressive ratio schedule of reinforcement. Intracerebral microdialysis revealed a slight but significant increase in dopamine activity in the shell of the nucleus accumbens of male rats when compared to intact female rats during CFB self-administration. The above differences may be caused by the hormonal (mainly estradiol) fluctuations that occur during the estrus cycle in intact females. Accordingly, in intact females CFB self-administration and dopamine activity were found to fluctuate across the estrus cycle, with lower parameters of CFB self-administration and lower dopamine activity in the Proestrus and Estrus phases vs. the Metestrus and Diestrus phases of the cycle. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of the estrous cycle and ovarian hormones on behavioral indices of anxiety in female rats.

PubMed

Mora, S; Dussaubat, N; Díaz-Véliz, G

1996-10-01

The influence of the estrous cycle and the effects of exogenous administration of estradiol and progesterone on level of anxiety were studied in intact and ovariectomized rats. Intact Sprague-Dawley female rats were classified according to the stages of estrous cycle. Another group of rats was ovariectomized bilaterally and, 14 days after surgery, they received estradiol benzoate (10 micrograms/kg, s.c.) and/or progesterone (25 mg/kg, s.c.) or corn oil (1 ml/kg). The behavioral tests began 3 h after estradiol or 6 h after progesterone and consisted of: (1) exploration of an elevated plus-maze; and (2) retention of a passive avoidance response. Open-arm exploration of the plus-maze varied according to light intensity and the stages of the estrous cycle. There was a slight increase in open-arm exploration by rats in metestrus, under high light intensity. Low light intensity increased the exploration of the open arms by rats in proestrus and estrus, compared to the other phases of the cycle. Retention of the passive avoidance response was inhibited during proestrus and estrus. Progesterone increased open-arm exploration of the plus-maze under high light conditions, whereas estradiol antagonized this effect. Retention of passive avoidance was inhibited after estradiol or progesterone injection. These results suggest that the behavioral indices of anxiety can vary across the estrous cycle, that low light intensities have anxiolytic-like effects, and that the sensitivity to this effect is higher during proestrus and estrus. This could be explained through modulatory effects of ovarian hormones upon behavioral indices of anxiety.

The influence of exogenous progestin on the occurrence of proestrous or estrous signs, plasma concentrations of luteinizing hormone and estradiol in deslorelin (GnRH agonist) treated anestrous bitches.

PubMed

Sung, M; Armour, A F; Wright, P J

2006-10-01

The objectives of this study were to confirm: (i) whether progestin treatment suppressed GnRH agonist-induced estrus in anestrous greyhound bitches; and (ii) the site of progestin action (i.e. pituitary, ovary). All bitches received a deslorelin implant on Day 0 and blood samples were taken from -1 h to +6 h. Five bitches were treated with megestrol acetate (2 mg/kg orally once daily) from -7 d to +6 d (Group 1) and 10 bitches were untreated controls (Group 2). Proestrous or estrous signs were observed in 4 of 5 bitches in Group 1, and 4 of 10 bitches in Group 2 (P = 0.28). The plasma LH responses (area under the curve from 0 to 6h after implantation) were higher (P = 0.008) in Group 2 than in Group 1. Plasma LH responses were similar (P = 0.59) in bitches showing signs of proestrus or estrus (responders) and in non-responders. The plasma estradiol responses (calculated as for LH response) were greater in Group 1 than in Group 2 (P = 0.048), and in responders than in non-responders (P = 0.02). (i) progestin treatment (a) did not suppress the incidence of bitches showing deslorelin-induced proestrus or estrus, and (b) was associated with a reduced pituitary responsiveness and an increased ovarian responsiveness to deslorelin treatment; (ii) the occurrence of proestrous or estrous signs reflected increased ovarian responsiveness to induced gonadotrophin secretion and not increased pituitary responsiveness to deslorelin.

Vaginocervical stimulation enhances social recognition memory in rats via oxytocin release in the olfactory bulb.

PubMed

Larrazolo-López, A; Kendrick, K M; Aburto-Arciniega, M; Arriaga-Avila, V; Morimoto, S; Frias, M; Guevara-Guzmán, R

2008-03-27

The ability of vaginocervical stimulation (VCS) to promote olfactory social recognition memory at different stages of the ovarian cycle was investigated in female rats. A juvenile social recognition paradigm was used and memory retention tested at 30 and 300 min after an adult was exposed to a juvenile during three 4-min trials. Results showed that an intact social recognition memory was present at 30 min in animals with or without VCS and at all stages of the estrus cycle. However, whereas no animals in any stage of the estrus cycle showed retention of the specific recognition memory at 300 min, those in the proestrus/estrus phase that received VCS 10 min before the trial started did. In vivo microdialysis studies showed that there was a significant release of oxytocin after VCS in the olfactory bulb during proestrus. There was also increased oxytocin immunoreactivity within the olfactory bulb after VCS in proestrus animals compared with diestrus ones. Furthermore, when animals received an infusion of an oxytocin antagonist directly into the olfactory bulb, or a systemic administration of alpha or beta noradrenaline-antagonists, they failed to show evidence for maintenance of a selective olfactory recognition memory at 300 min. Animals with vagus or pelvic nerve section also showed no memory retention when tested after 300 min. These results suggest that VCS releases oxytocin in the olfactory bulb to enhance the social recognition memory and that this may be due to modulatory actions on noradrenaline release. The vagus and pelvic nerves are responsible for carrying the information from the pelvic area to the CNS.

Synchronous Spike Patterns in Macaque Motor Cortex during an Instructed-Delay Reach-to-Grasp Task

PubMed Central

Torre, Emiliano; Quaglio, Pietro; Denker, Michael; Brochier, Thomas; Riehle, Alexa

2016-01-01

The computational role of spike time synchronization at millisecond precision among neurons in the cerebral cortex is hotly debated. Studies performed on data of limited size provided experimental evidence that low-order correlations occur in relation to behavior. Advances in electrophysiological technology to record from hundreds of neurons simultaneously provide the opportunity to observe coordinated spiking activity of larger populations of cells. We recently published a method that combines data mining and statistical evaluation to search for significant patterns of synchronous spikes in massively parallel spike trains (Torre et al., 2013). The method solves the computational and multiple testing problems raised by the high dimensionality of the data. In the current study, we used our method on simultaneous recordings from two macaque monkeys engaged in an instructed-delay reach-to-grasp task to determine the emergence of spike synchronization in relation to behavior. We found a multitude of synchronous spike patterns aligned in both monkeys along a preferential mediolateral orientation in brain space. The occurrence of the patterns is highly specific to behavior, indicating that different behaviors are associated with the synchronization of different groups of neurons (“cell assemblies”). However, pooled patterns that overlap in neuronal composition exhibit no specificity, suggesting that exclusive cell assemblies become active during different behaviors, but can recruit partly identical neurons. These findings are consistent across multiple recording sessions analyzed across the two monkeys. SIGNIFICANCE STATEMENT Neurons in the brain communicate via electrical impulses called spikes. How spikes are coordinated to process information is still largely unknown. Synchronous spikes are effective in triggering a spike emission in receiving neurons and have been shown to occur in relation to behavior in a number of studies on simultaneous recordings of few neurons. We recently published a method to extend this type of investigation to larger data. Here, we apply it to simultaneous recordings of hundreds of neurons from the motor cortex of macaque monkeys performing a motor task. Our analysis reveals groups of neurons selectively synchronizing their activity in relation to behavior, which sheds new light on the role of synchrony in information processing in the cerebral cortex. PMID:27511007

Synchronous Spike Patterns in Macaque Motor Cortex during an Instructed-Delay Reach-to-Grasp Task.

PubMed

Torre, Emiliano; Quaglio, Pietro; Denker, Michael; Brochier, Thomas; Riehle, Alexa; Grün, Sonja

2016-08-10

The computational role of spike time synchronization at millisecond precision among neurons in the cerebral cortex is hotly debated. Studies performed on data of limited size provided experimental evidence that low-order correlations occur in relation to behavior. Advances in electrophysiological technology to record from hundreds of neurons simultaneously provide the opportunity to observe coordinated spiking activity of larger populations of cells. We recently published a method that combines data mining and statistical evaluation to search for significant patterns of synchronous spikes in massively parallel spike trains (Torre et al., 2013). The method solves the computational and multiple testing problems raised by the high dimensionality of the data. In the current study, we used our method on simultaneous recordings from two macaque monkeys engaged in an instructed-delay reach-to-grasp task to determine the emergence of spike synchronization in relation to behavior. We found a multitude of synchronous spike patterns aligned in both monkeys along a preferential mediolateral orientation in brain space. The occurrence of the patterns is highly specific to behavior, indicating that different behaviors are associated with the synchronization of different groups of neurons ("cell assemblies"). However, pooled patterns that overlap in neuronal composition exhibit no specificity, suggesting that exclusive cell assemblies become active during different behaviors, but can recruit partly identical neurons. These findings are consistent across multiple recording sessions analyzed across the two monkeys. Neurons in the brain communicate via electrical impulses called spikes. How spikes are coordinated to process information is still largely unknown. Synchronous spikes are effective in triggering a spike emission in receiving neurons and have been shown to occur in relation to behavior in a number of studies on simultaneous recordings of few neurons. We recently published a method to extend this type of investigation to larger data. Here, we apply it to simultaneous recordings of hundreds of neurons from the motor cortex of macaque monkeys performing a motor task. Our analysis reveals groups of neurons selectively synchronizing their activity in relation to behavior, which sheds new light on the role of synchrony in information processing in the cerebral cortex. Copyright © 2016 Torre, et al.

Finite-time hybrid projective synchronization of the drive-response complex networks with distributed-delay via adaptive intermittent control

NASA Astrophysics Data System (ADS)

Cheng, Lin; Yang, Yongqing; Li, Li; Sui, Xin

2018-06-01

This paper studies the finite-time hybrid projective synchronization of the drive-response complex networks. In the model, general transmission delays and distributed delays are also considered. By designing the adaptive intermittent controllers, the response network can achieve hybrid projective synchronization with the drive system in finite time. Based on finite-time stability theory and several differential inequalities, some simple finite-time hybrid projective synchronization criteria are derived. Two numerical examples are given to illustrate the effectiveness of the proposed method.

Brain network dynamics characterization in epileptic seizures. Joint directed graph and pairwise synchronization measures

NASA Astrophysics Data System (ADS)

Rodrigues, A. C.; Machado, B. S.; Florence, G.; Hamad, A. P.; Sakamoto, A. C.; Fujita, A.; Baccalá, L. A.; Amaro, E.; Sameshima, K.

2014-12-01

Here we propose and evaluate a new approach to analyse multichannel mesial temporal lobe epilepsy EEG data from eight patients through complex network and synchronization theories. The method employs a Granger causality test to infer the directed connectivity graphs and a wavelet transform based phase synchronization measure whose characteristics allow studying dynamical transitions during epileptic seizures. We present a new combined graph measure that quantifies the level of network hub formation, called network hub out-degree, which closely reflects the level of synchronization observed during the ictus.

A Drive Method of Permanent Magnet Synchronous Motor Using Torque Angle Estimation without Position Sensor

NASA Astrophysics Data System (ADS)

Tanaka, Takuro; Takahashi, Hisashi

In some motor applications, it is very difficult to attach a position sensor to the motor in housing. One of the examples of such applications is the dental handpiece-motor. In those designs, it is necessary to drive highly efficiency at low speed and variable load condition without a position sensor. We developed a method to control a motor high-efficient and smoothly at low speed without a position sensor. In this paper, the method in which permanent magnet synchronous motor is controlled smoothly and high-efficient by using torque angle control in synchronized operation is shown. The usefulness is confirmed by experimental results. In conclusion, the proposed sensor-less control method has been achieved to be very efficiently and smoothly.

Research on the phase adjustment method for dispersion interferometer on HL-2A tokamak

NASA Astrophysics Data System (ADS)

Tongyu, WU; Wei, ZHANG; Haoxi, WANG; Yan, ZHOU; Zejie, YIN

2018-06-01

A synchronous demodulation system is proposed and deployed for CO2 dispersion interferometer on HL-2A, which aims at high plasma density measurements and real-time feedback control. In order to make sure that the demodulator and the interferometer signal are synchronous in phase, a phase adjustment (PA) method has been developed for the demodulation system. The method takes advantages of the field programmable gate array parallel and pipeline process capabilities to carry out high performance and low latency PA. Some experimental results presented show that the PA method is crucial to the synchronous demodulation system and reliable to follow the fast change of the electron density. The system can measure the line-integrated density with a high precision of 2.0 × 1018 m‑2.

Finite-time synchronization control of a class of memristor-based recurrent neural networks.

PubMed

Jiang, Minghui; Wang, Shuangtao; Mei, Jun; Shen, Yanjun

2015-03-01

This paper presents a global and local finite-time synchronization control law for memristor neural networks. By utilizing the drive-response concept, differential inclusions theory, and Lyapunov functional method, we establish several sufficient conditions for finite-time synchronization between the master and corresponding slave memristor-based neural network with the designed controller. In comparison with the existing results, the proposed stability conditions are new, and the obtained results extend some previous works on conventional recurrent neural networks. Two numerical examples are provided to illustrate the effective of the design method. Copyright © 2014 Elsevier Ltd. All rights reserved.

A rare case of uterine adenomyosis in a Siamese cat

PubMed Central

Bulman-Fleming, Julie

2008-01-01

A 12-year-old, female Siamese cat with a long-term history of megestrol acetate treatment for suppression of estrus was presented with vomiting and abdominal pain. Uterine adenomyosis was diagnosed after an ovariohysterectomy. PMID:18827849

Spectral Entropy Based Neuronal Network Synchronization Analysis Based on Microelectrode Array Measurements

PubMed Central

Kapucu, Fikret E.; Välkki, Inkeri; Mikkonen, Jarno E.; Leone, Chiara; Lenk, Kerstin; Tanskanen, Jarno M. A.; Hyttinen, Jari A. K.

2016-01-01

Synchrony and asynchrony are essential aspects of the functioning of interconnected neuronal cells and networks. New information on neuronal synchronization can be expected to aid in understanding these systems. Synchronization provides insight in the functional connectivity and the spatial distribution of the information processing in the networks. Synchronization is generally studied with time domain analysis of neuronal events, or using direct frequency spectrum analysis, e.g., in specific frequency bands. However, these methods have their pitfalls. Thus, we have previously proposed a method to analyze temporal changes in the complexity of the frequency of signals originating from different network regions. The method is based on the correlation of time varying spectral entropies (SEs). SE assesses the regularity, or complexity, of a time series by quantifying the uniformity of the frequency spectrum distribution. It has been previously employed, e.g., in electroencephalogram analysis. Here, we revisit our correlated spectral entropy method (CorSE), providing evidence of its justification, usability, and benefits. Here, CorSE is assessed with simulations and in vitro microelectrode array (MEA) data. CorSE is first demonstrated with a specifically tailored toy simulation to illustrate how it can identify synchronized populations. To provide a form of validation, the method was tested with simulated data from integrate-and-fire model based computational neuronal networks. To demonstrate the analysis of real data, CorSE was applied on in vitro MEA data measured from rat cortical cell cultures, and the results were compared with three known event based synchronization measures. Finally, we show the usability by tracking the development of networks in dissociated mouse cortical cell cultures. The results show that temporal correlations in frequency spectrum distributions reflect the network relations of neuronal populations. In the simulated data, CorSE unraveled the synchronizations. With the real in vitro MEA data, CorSE produced biologically plausible results. Since CorSE analyses continuous data, it is not affected by possibly poor spike or other event detection quality. We conclude that CorSE can reveal neuronal network synchronization based on in vitro MEA field potential measurements. CorSE is expected to be equally applicable also in the analysis of corresponding in vivo and ex vivo data analysis. PMID:27803660

Detecting synchronization clusters in multivariate time series via coarse-graining of Markov chains.

PubMed

Allefeld, Carsten; Bialonski, Stephan

2007-12-01

Synchronization cluster analysis is an approach to the detection of underlying structures in data sets of multivariate time series, starting from a matrix R of bivariate synchronization indices. A previous method utilized the eigenvectors of R for cluster identification, analogous to several recent attempts at group identification using eigenvectors of the correlation matrix. All of these approaches assumed a one-to-one correspondence of dominant eigenvectors and clusters, which has however been shown to be wrong in important cases. We clarify the usefulness of eigenvalue decomposition for synchronization cluster analysis by translating the problem into the language of stochastic processes, and derive an enhanced clustering method harnessing recent insights from the coarse-graining of finite-state Markov processes. We illustrate the operation of our method using a simulated system of coupled Lorenz oscillators, and we demonstrate its superior performance over the previous approach. Finally we investigate the question of robustness of the algorithm against small sample size, which is important with regard to field applications.

Regression analysis of sparse asynchronous longitudinal data

PubMed Central

Cao, Hongyuan; Zeng, Donglin; Fine, Jason P.

2015-01-01

Summary We consider estimation of regression models for sparse asynchronous longitudinal observations, where time-dependent responses and covariates are observed intermittently within subjects. Unlike with synchronous data, where the response and covariates are observed at the same time point, with asynchronous data, the observation times are mismatched. Simple kernel-weighted estimating equations are proposed for generalized linear models with either time invariant or time-dependent coefficients under smoothness assumptions for the covariate processes which are similar to those for synchronous data. For models with either time invariant or time-dependent coefficients, the estimators are consistent and asymptotically normal but converge at slower rates than those achieved with synchronous data. Simulation studies evidence that the methods perform well with realistic sample sizes and may be superior to a naive application of methods for synchronous data based on an ad hoc last value carried forward approach. The practical utility of the methods is illustrated on data from a study on human immunodeficiency virus. PMID:26568699

The effect of early to mid-gestational nutrient restriction on female offspring fertility and hypothalamic-pituitary-adrenal axis response to stress.

PubMed

Long, N M; Nijland, M J; Nathanielsz, P W; Ford, S P

2010-06-01

Primiparous ewes born as singletons to Rambouillet x Columbia crossbred ewes fed either 100% of NRC recommendations (control, Con; n = 7) or 50% of NRC (nutrient restricted, NR; n = 7) from d 28 through 78 postmating were utilized for this study. At 1 yr of age, a subset of ewes born to Con (n = 4) and NR (n = 4) mothers received jugular catheters and were subjected to a corticotrophin-releasing hormone (CRH)/arginine vasopressin (AVP) challenge, an ACTH challenge, and an isolation stress test, in which ACTH and cortisol responses were determined. A week after these challenges, estrus was monitored twice daily in all ewes from Con (n = 7) and NR mothers (n = 7). Once estrus was observed (d 0), daily blood samples were collected from ewes for progesterone through the subsequent estrus. Estrous detection and daily blood sampling were repeated during an estrous cycle in the next year, ewes were hand mated at the second estrus, and pregnancy was determined by delivery of a live lamb(s). Ewes from NR mothers tended (P = 0.10) to have a greater peak ACTH response after an intravenous CRH/AVP injection than ewes from Con mothers. The cortisol response of ewes to a CRH/AVP or ACTH challenge was not influenced by maternal nutrition. In contrast, ewes from Con mothers tended (P = 0.10) to release more ACTH in response to the isolation stress test and showed a greater (P = 0.04) cortisol release than ewes from NR mothers. Ewes from NR mothers exhibited decreased (P < 0.05) plasma progesterone in both yr 1 and 2 of the study compared with ewes from Con mothers. Furthermore, fewer (P < 0.0001) ewes from NR mothers produced a lamb (1 of 7) than ewes from Con mothers (7 of 7) during yr 2 of the study. These findings indicate that maternal undernutrition during early gestation may affect stress responses by the offspring, but has limited impact on hypothalamo-pituitary-adrenal sensitivity. Furthermore, offspring of NR ewes exhibited reduced progesterone secretion during the luteal phase of their estrous cycles and a markedly reduced fertility compared with offspring from Con ewes.

Reproductive and growth responses of gilts to exogenous porcine pituitary growth hormone.

PubMed

Bryan, K A; Hammond, J M; Canning, S; Mondschein, J; Carbaugh, D E; Clark, A M; Hagen, D R

1989-01-01

Forty gilts (mean wt = 72 kg) were administered daily either vehicle (C = control) or 70 micrograms porcine growth hormone (pGH)/kg BW. After 30 d of treatment, eight gilts per group (Exp. 1) were slaughtered and blood, uteri and ovaries were collected. Follicular fluid (FFl) was collected and granulosa cells (GC) were cultured. The remaining gilts (Exp. 2) were treated for up to 35 additional days and examined twice daily for estrus. Estrusal gilts were removed from the experiment. Noncyclic gilts (n = 9 of 12 pGH; n = 4 of 12 C) were slaughtered on d 66 and their ovaries were examined. Ovarian weights were not different for pGH and C gilts in either Exp. 1 (P greater than .1) or Exp. 2 (P = .09). Uterine weights were greater for pGH-treated than for C gilts (P less than .007) in Exp. 1, but not in Exp. 2. Concentrations of estradiol (E2) in plasma and FF1 and of progesterone (P) in plasma and FF1 were not different for pGH and C gilts. Concentrations of insulin-like growth factor-I (IGF-I) in FF1 and in serum were greater for pGH than for C gilts (P less than .01). Concentration of P in serum-free medium of cultured GC was lower for GH than for C (P less than .05) in the presence or absence of gonadotropins in Exp. 1. The FSH-stimulated secretion of P was also lower for GC of pGH-treated gilts in Exp. 2, indicating a failure of GC to differentiate in culture. Only one pGH gilts in Exp. 2 manifested estrus, compared with seven C gilts (P less than .025). In Exp. 1, ADG was higher (P less than .03) and feed/gain lower (P less than .07) for pGH gilts. Longissimus muscle area (LMA) was not different (P = .19) between groups. Backfat thickness (BF) was lower (P less than .005) in pGH than in C in both Exp. 1 and 2. We conclude that exogenous pGH increased growth rate, improved feed efficiency and altered carcass traits in gilts. However, these effects were associated with impaired ovarian development of prepubertal gilts and a low incidence of estrus.

Endometrial IL-1beta, IL-6 and TNF-alpha, mRNA expression in mares resistant or susceptible to post-breeding endometritis. Effects of estrous cycle, artificial insemination and immunomodulation.

PubMed

Fumuso, Elida; Giguère, Steeve; Wade, José; Rogan, Dragan; Videla-Dorna, Ignacio; Bowden, Raúl A

2003-11-15

Endometrial mRNA expression of the pro-inflammatory cytokines interleukin-1beta (IL-1beta), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-alpha) was assessed in mares resistant (RM) or susceptible (SM) to persistent post-breeding endometritis (PPBE). Eight RM and eight SM, were selected based on reproductive records and functional tests out of a herd of 2,000 light cross-type mares. Three experiments were done to study transcription patterns in (i) basal conditions; (ii) after artificial insemination (AI); and (iii) after administration of an immunomodulator at time of artificial insemination. Endometrial biopsies were taken during consecutive cycles: (i) at estrus, when follicles reached 35 mm and at diestrus (7 +/- 1 days after ovulation); (ii) at 24 h post-AI, with dead semen (estrus) and in diestrus; (iii) at 24 h after treatment with a Mycobacterium phlei cell-wall extract (MCWE) preparation and AI (with dead semen), and at diestrus. mRNA expression was quantitated by real time PCR. Under basal conditions, SM had significantly higher mRNA expression of all cytokines in estrus and of IL-1beta and TNF-alpha in diestrus, compared to RM. After AI, there were no differences between RM and SM in estrus; however, mRNA expression for all three pro-inflammatory cytokines was higher than under basal conditions. In diestrus, RM showed significantly lower IL-1beta and TNF-alpha mRNA expression than SM. When MCWE was administered at time of AI, no differences between cytokine induction from RM and SM were found. Globally, mRNA expression for all three cytokines correlated well among themselves when expression was high. The present study showed that (i) in basal conditions RM had lower mRNA expression of pro-inflammatory cytokines than SM with no effect of estrous cycle; (ii) AI upregulated mRNA expression for all three cytokines in both RM and SM, with persistance in diestrus in the latter; (iii) treatment with MCWE at time of AI down-regulated mRNA expression of IL-1 with significant effects in SM which behaved like RM. Immunomodulation with MCWE could be of help in restoring homeostatic local inflammatory mechanisms, thus assisting in the prophylaxis of post-breeding endometritis in mares.

Protein and glucogenic precursor supplementation: a nutritional strategy to increase reproductive and economic output.

PubMed

Mulliniks, J T; Cox, S H; Kemp, M E; Endecott, R L; Waterman, R C; Vanleeuwen, D M; Torell, L A; Petersen, M K

2011-10-01

Reproductive performance in young beef cows is often compromised due to a mismatch of physiological demands and suboptimal environmental conditions. Studies conducted at the Corona Range and Livestock Research Center from 2000 to 2007 evaluated 3 postpartum supplement strategies that varied in the amount of glucogenic potential (GP) supplied. Reproductive variables, milk production, and serum metabolites were used to assess supplement effectiveness and economics associated with 2- and 3-yr-old beef cows (n = 379) grazing native range. Supplements were individually fed twice/week at 1,135 g/d (2003 to 2004) or 908 g/d (all other years) and provided 1) 327 g of CP, 109 to 118 g of RUP (CON); 2) 327 to 341 g of CP, 142 to 157 g of RUP (RUP); or 3) 327 g of CP, 151 to 173 g of RUP + 40 to 100 g of propionate salt (PS; RUP+PS). Ultimately, total GP for CON, RUP, and RUP+PS was 44 to 47, 57 to 70, and 93 to 141 g, respectively. Blood samples were collected once/week (2000) or twice/week (2001 to 2007) for progesterone analysis to estimate days to resumption of estrus. Cows were exposed to bulls for 60 d or less, and pregnancy was confirmed by rectal palpation at weaning. Days to resumption of estrus after calving decreased linearly (P = 0.02), resulting in an increased pregnancy rate (P = 0.03) with increasing GP. Milk production exhibited a quadratic (P = 0.04) response to increasing GP, with cows fed RUP producing the most amount of milk. However, a linear decrease (P = 0.07) in days from BW nadir to estrus was found with increasing GP. Total kilograms of calf weaned per cow exposed for the supplemental year and subsequent year was increased linearly (P = 0.07) with increased GP. The improvement in pregnancy rate by supplementing RUP+PS resulted in an increase in total revenue of 18% compared with CON-fed cows and 9.5% compared with RUP-fed cows in the subsequent year after supplementation. These data suggest feeding young cows additional GP in the form of PS allows for partitioning of nutrients away from milk production and toward reproduction, allowing for increased profitability by increasing pregnancy rates and decreasing days to resumption of estrus.

Chaos synchronization in networks of semiconductor superlattices

NASA Astrophysics Data System (ADS)

Li, Wen; Aviad, Yaara; Reidler, Igor; Song, Helun; Huang, Yuyang; Biermann, Klaus; Rosenbluh, Michael; Zhang, Yaohui; Grahn, Holger T.; Kanter, Ido

2015-11-01

Chaos synchronization has been demonstrated as a useful building block for various tasks in secure communications, including a source of all-electronic ultrafast physical random number generators based on room temperature spontaneous chaotic oscillations in a DC-biased weakly coupled GaAs/Al0.45Ga0.55As semiconductor superlattice (SSL). Here, we experimentally demonstrate the emergence of several types of chaos synchronization, e.g. leader-laggard, face-to-face and zero-lag synchronization in network motifs of coupled SSLs consisting of unidirectional and mutual coupling as well as self-feedback coupling. Each type of synchronization clearly reflects the symmetry of the topology of its network motif. The emergence of a chaotic SSL without external feedback and synchronization among different structured SSLs open up the possibility for advanced secure multi-user communication methods based on large networks of coupled SSLs.

Introduction to focus issue: Synchronization in large networks and continuous media—data, models, and supermodels

NASA Astrophysics Data System (ADS)

Duane, Gregory S.; Grabow, Carsten; Selten, Frank; Ghil, Michael

2017-12-01

The synchronization of loosely coupled chaotic systems has increasingly found applications to large networks of differential equations and to models of continuous media. These applications are at the core of the present Focus Issue. Synchronization between a system and its model, based on limited observations, gives a new perspective on data assimilation. Synchronization among different models of the same system defines a supermodel that can achieve partial consensus among models that otherwise disagree in several respects. Finally, novel methods of time series analysis permit a better description of synchronization in a system that is only observed partially and for a relatively short time. This Focus Issue discusses synchronization in extended systems or in components thereof, with particular attention to data assimilation, supermodeling, and their applications to various areas, from climate modeling to macroeconomics.

Introduction to focus issue: Synchronization in large networks and continuous media-data, models, and supermodels.

PubMed

Duane, Gregory S; Grabow, Carsten; Selten, Frank; Ghil, Michael

2017-12-01

The synchronization of loosely coupled chaotic systems has increasingly found applications to large networks of differential equations and to models of continuous media. These applications are at the core of the present Focus Issue. Synchronization between a system and its model, based on limited observations, gives a new perspective on data assimilation. Synchronization among different models of the same system defines a supermodel that can achieve partial consensus among models that otherwise disagree in several respects. Finally, novel methods of time series analysis permit a better description of synchronization in a system that is only observed partially and for a relatively short time. This Focus Issue discusses synchronization in extended systems or in components thereof, with particular attention to data assimilation, supermodeling, and their applications to various areas, from climate modeling to macroeconomics.

Projective synchronization of nonidentical fractional-order neural networks based on sliding mode controller.

PubMed

Ding, Zhixia; Shen, Yi

2016-04-01

This paper investigates global projective synchronization of nonidentical fractional-order neural networks (FNNs) based on sliding mode control technique. We firstly construct a fractional-order integral sliding surface. Then, according to the sliding mode control theory, we design a sliding mode controller to guarantee the occurrence of the sliding motion. Based on fractional Lyapunov direct methods, system trajectories are driven to the proposed sliding surface and remain on it evermore, and some novel criteria are obtained to realize global projective synchronization of nonidentical FNNs. As the special cases, some sufficient conditions are given to ensure projective synchronization of identical FNNs, complete synchronization of nonidentical FNNs and anti-synchronization of nonidentical FNNs. Finally, one numerical example is given to demonstrate the effectiveness of the obtained results. Copyright © 2016 Elsevier Ltd. All rights reserved.

PTTI 2030 - Time Transfer and Applications in 2030

DTIC Science & Technology

2010-01-01

today’s society is paramount. Every day billions of people worldwide depend on some level of time synchronization , and timing laboratories require...applications as an inexpensive way to disseminate GPS-acquired time and frequency among groups, or as a backup method of time synchronization in the...strictly for timing use would be very expensive, perhaps prohibitive. ADVANTAGES OF AN IEEE-1588-ENABLED POWER GRID Time synchronization in

Synchronization-insensitive video watermarking using structured noise pattern

NASA Astrophysics Data System (ADS)

Setyawan, Iwan; Kakes, Geerd; Lagendijk, Reginald L.

2002-04-01

For most watermarking methods, preserving the synchronization between the watermark embedded in a digital data (image, audio or video) and the watermark detector is critical to the success of the watermark detection process. Many digital watermarking attacks exploit this fact by disturbing the synchronization of the watermark and the watermark detector, and thus disabling proper watermark detection without having to actually remove the watermark from the data. Some techniques have been proposed in the literature to deal with this problem. Most of these techniques employ methods to reverse the distortion caused by the attack and then try to detect the watermark from the repaired data. In this paper, we propose a watermarking technique that is not sensitive to synchronization. This technique uses a structured noise pattern and embeds the watermark payload into the geometrical structure of the embedded pattern.

Method and system for controlling a synchronous machine over full operating range

DOEpatents

Walters, James E.; Gunawan, Fani S.; Xue, Yanhong

2002-01-01

System and method for controlling a synchronous machine are provided. The method allows for calculating a stator voltage index. The method further allows for relating the magnitude of the stator voltage index against a threshold voltage value. An offset signal is generated based on the results of the relating step. A respective state of operation of the machine is determined. The offset signal is processed based on the respective state of the machine.

Synchronization for Optical PPM Signals

NASA Technical Reports Server (NTRS)

Vilnrotter, V. A.

1985-01-01

Method based on statistical properties of weak pulse-positionmodulated (PPM) signal enables synchronization of receiver clock with received-signal time base. Method applies to weak optical M-ary PPM signals, for which there is only one pulse of length Tp transmitted during one of timeslots of length T in each successive interval of M timeslots. Method requires small dead time, Td, at beginning and end of each timeslot, during which pulse amplitude is zero.

Analysis of the Multiple-Solution Response of a Flexible Rotor Supported on Non-Linear Squeeze Film Dampers

NASA Astrophysics Data System (ADS)

ZHU, C. S.; ROBB, D. A.; EWINS, D. J.

2002-05-01

The multiple-solution response of rotors supported on squeeze film dampers is a typical non-linear phenomenon. The behaviour of the multiple-solution response in a flexible rotor supported on two identical squeeze film dampers with centralizing springs is studied by three methods: synchronous circular centred-orbit motion solution, numerical integration method and slow acceleration method using the assumption of a short bearing and cavitated oil film; the differences of computational results obtained by the three different methods are compared in this paper. It is shown that there are three basic forms for the multiple-solution response in the flexible rotor system supported on the squeeze film dampers, which are the resonant, isolated bifurcation and swallowtail bifurcation multiple solutions. In the multiple-solution speed regions, the rotor motion may be subsynchronous, super-subsynchronous, almost-periodic and even chaotic, besides synchronous circular centred, even if the gravity effect is not considered. The assumption of synchronous circular centred-orbit motion for the journal and rotor around the static deflection line can be used only in some special cases; the steady state numerical integration method is very useful, but time consuming. Using the slow acceleration method, not only can the multiple-solution speed regions be detected, but also the non-synchronous response regions.

Simultaneous determination of rosuvastatin and propranolol in their binary mixture by synchronous spectrofluorimetry

NASA Astrophysics Data System (ADS)

El-Abasawi, Nasr M.; Attia, Khalid A. M.; Abo-serie, Ahmad A. M.; Morshedy, Samir; Abdel-Fattah, Ashraf

2018-06-01

Simultaneous determination of rosuvastatin calcium and propranolol hydrochloride using the first derivative synchronous spectrofluorimetry was described. This method involves measuring the synchronous fluorescence of both drugs in ethanol using, Δ λ = 60 nm then the first derivative was recorded and the peak amplitudes were measured at 350 and 374 nm for rosuvastatin calcium and propranolol hydrochloride, respectively. Under the optimum conditions, the linear ranges of rosuvastatin calcium and propranolol hydrochloride were 0.2-2 μg/mL and 0.1-1 μg/mL, respectively. The method was used for quantitative analysis of the drugs in raw materials and pharmaceutical dosage form. The validity of the proposed method was assessed according to an international conference on harmonization (ICH) guidelines.

Equilibrium points and associated periodic orbits in the gravity of binary asteroid systems: (66391) 1999 KW4 as an example

NASA Astrophysics Data System (ADS)

Shi, Yu; Wang, Yue; Xu, Shijie

2018-04-01

The motion of a massless particle in the gravity of a binary asteroid system, referred as the restricted full three-body problem (RF3BP), is fundamental, not only for the evolution of the binary system, but also for the design of relevant space missions. In this paper, equilibrium points and associated periodic orbit families in the gravity of a binary system are investigated, with the binary (66391) 1999 KW4 as an example. The polyhedron shape model is used to describe irregular shapes and corresponding gravity fields of the primary and secondary of (66391) 1999 KW4, which is more accurate than the ellipsoid shape model in previous studies and provides a high-fidelity representation of the gravitational environment. Both of the synchronous and non-synchronous states of the binary system are considered. For the synchronous binary system, the equilibrium points and their stability are determined, and periodic orbit families emanating from each equilibrium point are generated by using the shooting (multiple shooting) method and the homotopy method, where the homotopy function connects the circular restricted three-body problem and RF3BP. In the non-synchronous binary system, trajectories of equivalent equilibrium points are calculated, and the associated periodic orbits are obtained by using the homotopy method, where the homotopy function connects the synchronous and non-synchronous systems. Although only the binary (66391) 1999 KW4 is considered, our methods will also be well applicable to other binary systems with polyhedron shape data. Our results on equilibrium points and associated periodic orbits provide general insights into the dynamical environment and orbital behaviors in proximity of small binary asteroids and enable the trajectory design and mission operations in future binary system explorations.

Sex pheromone in the dog.

PubMed

Goodwin, M; Gooding, K M; Regnier, F

1979-02-09

Methyl p-hydroxybenzoate has been identified in the vaginal secretions of female dogs in estrus. When small amounts of this compound were applied to the vulvas of anestrous or spayed females, males placed with these females became sexually aroused and attempted to mount them.

Testing a Firefly-Inspired Synchronization Algorithm in a Complex Wireless Sensor Network

PubMed Central

Hao, Chuangbo; Song, Ping; Yang, Cheng; Liu, Xiongjun

2017-01-01

Data acquisition is the foundation of soft sensor and data fusion. Distributed data acquisition and its synchronization are the important technologies to ensure the accuracy of soft sensors. As a research topic in bionic science, the firefly-inspired algorithm has attracted widespread attention as a new synchronization method. Aiming at reducing the design difficulty of firefly-inspired synchronization algorithms for Wireless Sensor Networks (WSNs) with complex topologies, this paper presents a firefly-inspired synchronization algorithm based on a multiscale discrete phase model that can optimize the performance tradeoff between the network scalability and synchronization capability in a complex wireless sensor network. The synchronization process can be regarded as a Markov state transition, which ensures the stability of this algorithm. Compared with the Miroll and Steven model and Reachback Firefly Algorithm, the proposed algorithm obtains better stability and performance. Finally, its practicality has been experimentally confirmed using 30 nodes in a real multi-hop topology with low quality links. PMID:28282899