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Sample records for cow physiological adaptations

  1. Physiological adaptations and ovarian cyclicity of Holstein and Montbéliarde cows under two low-input production systems.

    PubMed

    Pires, J A A; Chilliard, Y; Delavaud, C; Rouel, J; Pomiès, D; Blanc, F

    2015-12-01

    The objective was to study milk production, body reserve mobilization, metabolic and hormonal profiles, and ovarian cyclicity of Holstein-Friesian (HOLS) and Montbéliarde (MONT) cows under two low-input dairy production systems with seasonal spring calving: an extensive (EXT; 12 HOLS and 12 MONT) based on permanent diversified grasslands and zero concentrate, and a semi-extensive (SEMI; 12 HOLS and 10 MONT) based on established temporary grasslands and up to 4 kg/day of concentrate. Individual measurements were performed between -4 and 12 weeks of lactation. Cows in EXT secreted less milk (22.1 v. 24.4 kg/day), protein (660 v. 755 g/day) and energy (67.7 v. 74.4 MJ/day), had greater plasma ?-hydroxybutyrate (BHBA) (0.97 v. 0.69 mM), lower glucose (59.0 v. 62.0 mg/dl) and IGF-1 (62 v. 71 ng/ml), lower milk fat concentration in fatty acids originating from de novo synthesis (e.g. ? 10:0 to 15:0) and greater concentration of those derived in part from mobilization of fat reserves (e.g. 18:0 and ?>C16), and showed greater frequency of abnormal ovarian cycles compared with SEMI. Across production systems, HOLS produced more milk (24.7 v. 21.8 kg/day), protein (738 v. 674 g/day) and fat (939 v. 819 g/day), secreted more energy (75.1 v. 67.0 MJ/day), lost more body condition score (BCS) (1.41 v. 1.03) and reached a lower BCS nadir (1.12 v. 1.43), had greater plasma BHBA (0.91 v. 0.75 mM), lower insulin (15.9 v. 17.2 µIU/ml) and tended to have lower glucose (59.6 v. 61.4 mg/dl), had lower milk fat concentration in ? 10:0 to 15:0, tended to have higher ?>C16 and tended to show more abnormal estrous cycles compared with MONT. Ultrasound measurements did not differentiate fat mobilization and were confounded by breed differences of skin thickness. The greater nutrient allowance in SEMI improved indicators of physiological status and ovarian function during early lactation compared with EXT, but did not attenuate body reserve mobilization because cows prioritized milk secretion. HOLS secreted more nutrients than MONT but lost more BCS, which negatively affected nutritional balance and tended to affect ovarian cyclicity during early lactation. Breed by system interactions were not observed except for a few variables. PMID:26189792

  2. COW EFFICIENCY AND ADAPTATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Efficiency of beef production is one of those terms that probably means something different to each person discussing the topic. Certainly, efficiency means something different to the packer than to the feeder or cow-calf producer. Beef production practices, and especially breeding, have been larg...

  3. Physiological responses to repeated transportation of gestating Brahman cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The transportation process acts as a stressor with adverse effects on animal health and performance. The purpose of this study was to examine physiological responses to repeated transportation of gestating Brahman cows, previously classified as mature cows, into temperament groups of calm, moderate,...

  4. Physiological and metabolic responses of gestating Brahaman cows to repeated transportation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this study was to examine physiological and metabolic responses to repeated transportation of gestating Brahman cows, previously classified as mature cows into temperament groups of Calm, Intermediate, or Temperamental. Brahman cows (n = 48) were subjected to 2 hours of transport (TRA...

  5. Cooling cows efficiently with sprinklers: Physiological responses to water spray.

    PubMed

    Chen, Jennifer M; Schütz, Karin E; Tucker, Cassandra B

    2015-10-01

    Dairies in the United States commonly cool cattle with sprinklers mounted over the feed bunk that intermittently spray the cows' backs. These systems use potable water-an increasingly scarce resource-but there is little experimental evidence about how much is needed to cool cows or about droplet size, which is thought to affect hair coat penetration. Our objectives were to determine how sprinkler flow rate and droplet size affect physiological measures of heat load in a hot, dry climate, and to evaluate cooling effectiveness against water use. The treatments were an unsprayed control and 6 soaker nozzles that delivered four 3-min spray applications of 0.4, 1.3, or ?4.5 L/min (with 2 droplet sizes within each flow rate) and resulting in 30 to 47% of spray directly wetting each cow. Data were collected from high-producing lactating Holsteins (n=19) tested individually in ambient conditions (air temperature=31.2±3.8°C, mean ± standard deviation). Cows were restrained in headlocks for 1h and received 1 treatment/d for 3d each, with order of exposure balanced in a crossover design. When cows were not sprayed, physiological measures of heat load increased during the 1-h treatment. All measures responded rapidly to spray: skin temperature decreased during the first water application, and respiration rate and body temperature did so before the second. Droplet size had no effect on cooling, but flow rate affected several measures. At the end of 1h, 0.4 L/min resulted in lower respiration rate and skin temperature on directly sprayed body parts relative to the control but not baseline values, and body temperature increased to 0.2°C above baseline. When 1.3 or ?4.5 L/min was applied, respiration rate was lower than the control and decreased relative to baseline, and body temperature stayed below baseline for at least 30min after treatment ended. The treatment that best balanced cooling effectiveness against water usage was 1.3 L/min: although ?4.5 L/min reduced respiration rate relative to baseline by 4 more breaths/min than 1.3L/min did (-13 vs. -9 breaths/min, respectively), each additional liter of water decreased this measure by only ?0.1 breaths/min (?1% of the total reduction achieved using 1.3 L/min). We found similar water efficiency patterns for skin temperature and the amount of time that body temperature remained below baseline after treatment ended. Thus, when using this intermittent spray schedule in a hot, dry climate, applying at least 1.3 L/min improved cooling, but above this, additional physiological benefits were relatively minor. PMID:26233441

  6. Metabolic Heat Stress Adaption in Transition Cows: Differences in Macronutrient Oxidation between Late-Gestating and Early-Lactating German Holstein Dairy Cows

    PubMed Central

    Derno, Michael; Otten, Winfried; Mielenz, Manfred; Nürnberg, Gerd

    2015-01-01

    High ambient temperatures have severe adverse effects on biological functions of high-yielding dairy cows. The metabolic adaption to heat stress was examined in 14 German Holsteins transition cows assigned to two groups, one heat-stressed (HS) and one pair-fed (PF) at the level of HS. After 6 days of thermoneutrality and ad libitum feeding (P1), cows were challenged for 6 days (P2) by heat stress (temperature humidity index (THI) = 76) or thermoneutral pair-feeding in climatic chambers 3 weeks ante partum and again 3 weeks post-partum. On the sixth day of each period P1 or P2, oxidative metabolism was analyzed for 24 hours in open circuit respiration chambers. Water and feed intake, vital parameters and milk yield were recorded. Daily blood samples were analyzed for glucose, ?-hydroxybutyric acid, non-esterified fatty acids, urea, creatinine, methyl histidine, adrenaline and noradrenaline. In general, heat stress caused marked effects on water homeorhesis with impairments of renal function and a strong adrenergic response accompanied with a prevalence of carbohydrate oxidation over fat catabolism. Heat-stressed cows extensively degraded tissue protein as reflected by the increase of plasma urea, creatinine and methyl histidine concentrations. However, the acute metabolic heat stress response in dry cows differed from early-lactating cows as the prepartal adipose tissue was not refractory to lipolytic, adrenergic stimuli, and the rate of amino acid oxidation was lower than in the postpartal stage. Together with the lower endogenous metabolic heat load, metabolic adaption in dry cows is indicative for a higher heat tolerance and the prioritization of the nutritional requirements of the fast-growing near-term fetus. These findings indicate that the development of future nutritional strategies for attenuating impairments of health and performance due to ambient heat requires the consideration of the physiological stage of dairy cows. PMID:25938406

  7. The effects of providing portable shade at pasture on dairy cow behavior and physiology.

    PubMed

    Palacio, S; Bergeron, R; Lachance, S; Vasseur, E

    2015-09-01

    Access to pasture has advantages for cows such as reduced lameness and improved udder health, but also may expose cows to stressors such as extreme heat. The objective of this study was to understand how portable shade affected physiological and behavioral responses of pastured dairy cows in a Canadian summer. Over 8wk, a total of 24 lactating Holstein cows were separated into 2 treatments, one with access to shade and a control without access to shade. The cows were pastured in groups of 4, with 3 field sections per treatment. Instantaneous scan sampling of behaviors (drinking, lying, grazing, other) performed in the shade or not were recorded every 5min for 3h/d during the hottest part of the day (peak hours: 1130-1530h) 3d/wk. Ambient temperature, humidity, and vaginal temperature were recorded at 10-min intervals. Daily milk production was also recorded. Differences between treatments by week were analyzed using the generalized linear mixed model with group as random effect and treatment as fixed effect. Cows with shade access were observed at the water trough up to 6.42 times less and lying down up to 1.75 times more. Cows with shade access grazed up to 1.5 times more but only when the temperature-humidity index was above their comfort threshold (?72) during the hottest part of the day (wk 2). Cows sought shade when it was made available, but spent less than half of their time observed (%) in the shade (40.8±4.67) with the exception of wk 2 when most of the time was spent under the shade (74.3±4.77). Daily lying time was highest during peak hours for cows with shade access. However, no overall difference in total lying time between the 2 treatments was observed. No differences were found in vaginal temperature or milk production between treatments with the exception of wk 1 for daily milk production, which was higher for cows in the control treatment. In conclusion, cows sought shade when it was provided at pasture, whereas cows without access to shade seemed to alter their behavior to cope with heat stress, as seen from the lack of physiological differences between treatments. The results indicate that providing cows with access to pasture under a temperate climate does not seem to have any detrimental physiological or production effects and providing them with shade can potentially decrease production costs and help with water conservation strategies as fewer cows were observed at the water when shade was provided. PMID:26162795

  8. Physiologic adaptation to space - Space adaptation syndrome

    NASA Technical Reports Server (NTRS)

    Vanderploeg, J. M.

    1985-01-01

    The adaptive changes of the neurovestibular system to microgravity, which result in space motion sickness (SMS), are studied. A list of symptoms, which range from vomiting to drowsiness, is provided. The two patterns of symptom development, rapid and gradual, and the duration of the symptoms are described. The concept of sensory conflict and rearrangements to explain SMS is being investigated.

  9. Using water to cool cattle: behavioral and physiological changes associated with voluntary use of cow showers.

    PubMed

    Legrand, A; Schütz, K E; Tucker, C B

    2011-07-01

    Water is commonly used to cool cattle in summer either at milking or over the feed bunk, but little research has examined how dairy cows voluntarily use water separate from these locations. The objectives were to describe how and when dairy cattle voluntarily used an overhead water source separate from other resources, such as feed, and how use of this water affected behavioral and physiological indicators of heat stress. Half of the 24 nonlactating cattle tested had access to a "cow shower" composed of 2 shower heads activated by a pressure-sensitive floor. All animals were individually housed to prevent competition for access to the shower. Over 5 d in summer (air temperature=25.3±3.3°C, mean ± standard deviation), cattle spent 3.0±2.1 h/24h in the shower, but considerable variability existed between animals (individual daily values ranged from 0.0 to 8.2 h/24h). A portion of this variation can be explained by weather; shower use increased by 0.3h for every 1°C increase in ambient temperature. Cows preferentially used the shower during the daytime, with 89±12% of the time spent in the shower between 1000 and 1900 h. Respiration rate and skin temperature did not differ between treatments [53 vs. 61 breaths/min and 35.0 vs. 35.4°C in shower and control cows, respectively; standard error of the difference (SED)=5.6 breaths/min and 0.49°C]. In contrast, body temperature of cows provided with a shower was 0.2°C lower than control cows in the evening (i.e., 1800 to 2100h; SED=0.11°C). Cows with access to a shower spent half as much time near the water trough than control animals, and this pattern became more pronounced as the temperature-humidity index increased. In addition, cattle showed other behavioral changes to increasing heat load; they spent less time lying when heat load index increased, but the time spent lying, feeding, and standing without feeding did not differ between treatments. Cows had higher respiration rate, skin temperature, and body temperature as heat load index increased, regardless of treatment. These data suggest that cattle, when given the opportunity, will make considerable use of a shower to reduce heat load, but that individuals are highly variable in their use of this resource. The variability between cows indicates that the behavioral response to water is likely an important, but poorly understood, consideration in the design of sprinkler systems used for summer cooling. PMID:21700023

  10. Influence of the physiological state on infestation by Rhipicephalus microplus in dairy cows.

    PubMed

    da Silva, Jenevaldo Barbosa; Rangel, Charles Passos; de Azevedo Baêta, Bruna; da Fonseca, Adivaldo Henrique

    2013-02-01

    The purpose of this study was to identify the influence of physiological state, season, breed, number of lactations, dairy productivity, and stocking rate on infestation by Rhipicephalus microplus in dairy cows. Two hundred cows were selected through proportional representative sampling at the Seropédica Experimental Station (Pesagro-Rio), Brazil. Fully or partially engorged R. microplus females measuring between 4.5 and 8.0mm were counted on the right side of each animal. The tick infestation prevalence data were analyzed in relation to the risk factors, using multiple logistic regression. Associations between prevalence and its possible influencing determinants were measured using odds ratios. The average tick count of cows during the peripartum and lactation periods was significantly higher (p<0.05; OR=4.82) than the count in dry cows. Taurine animals showed significantly higher infestation (p<0.05; OR=3.28) than pure zebuine animals. Among cross-bred animals, the infestation was higher (p<0.05) in F1 animals (1/2 taurine×1/2 zebuine) than in Girolando animals (5/8 zebuine×3/8 taurine). Primiparous cows (p<0.05) had significantly heavier infestations than multiparous cows. Dairy production showed a positive correlation with tick infestation (p<0.03; OR=2.94), such that the most productive animals were the most parasitized ones. Animals kept at high densities were significantly more heavily infested (p<0.05, OR=6.32) than animals kept at low density. First-lactation and high-productivity taurine animals were more vulnerable to R. microplus, thus comprising a high-risk group in dairy herds. PMID:23238247

  11. Diet and cooling interactions on physiological responses of grazing dairy cows, milk production and composition

    NASA Astrophysics Data System (ADS)

    Gallardo, M. R.; Valtorta, S. E.; Leva, P. E.; Gaggiotti, M. C.; Conti, G. A.; Gregoret, R. F.

    2005-11-01

    The objective of this trial was to evaluate the effects of diet and cooling in the holding pen before milking on rectal temperature, respiration rate and milk production and composition. Fifty-eight lactating Holstein cows were used in a factorial split-plot design, at Rafaela Experimental Station from 12 January to 3 March 2003. The treatments were combinations of two diets: control (CD) and balanced (BD) with two levels of cooling before milking: none (NSF) and a sprinkler and fans (SF). Forage:concentrate ratios for CD and BD were 81:19 and 68:32, respectively. Cows were milked twice daily. Milk production was recorded daily, and milk composition (fat, protein, lactose and urea) was analysed twice a week. The physiological data were recorded once a week, before the cattle entered the holding pen and after milking, in the afternoon. Average maximum weekly temperature humidity index was 75.4 and ranged from 61.4 to 83. There were highly significant effects of cooling on physiological responses. Milk production was affected by diet and cooling, with no interaction; the highest and lowest production of milk was 22.42 and 20.07 l/cow per day, for BD+SF and CD+NSF, respectively. Protein was affected by diet, and was higher for BD (3.17 vs. 3.08%). There were interaction effects on milk fat at the 8% level, the highest concentration being 3.65% for BD+NFS. It was concluded that under grazing conditions, cooling by sprinkler and fans before milking improves the comfort of dairy cows, and that the effects on milk production and composition are enhanced when diets are specially formulated for heat-stress periods.

  12. Resistance Training: Physiological Responses and Adaptations (Part 3 of 4).

    ERIC Educational Resources Information Center

    Fleck, Steven J.; Kraemer, William J.

    1988-01-01

    The physiological responses and adaptations which occur as a result of resistance training, such as cardiovascular responses, serum lipid count, body composition, and neural adaptations are discussed. Changes in the endocrine system are also described. (JL)

  13. Short dry period management improves peripartum ruminal adaptation in dairy cows.

    PubMed

    Jolicoeur, M S; Brito, A F; Santschi, D E; Pellerin, D; Lefebvre, D; Berthiaume, R; Girard, C L

    2014-12-01

    The present study aimed to determine whether the improvement in postpartum energy balance frequently reported in cows under short dry period management could be due to an improvement in ruminal function related to the reduction in the number of diet changes before calving. Six multiparous and 6 primiparous Holstein cows equipped with ruminal cannula were assigned to 6 blocks of 2 cows each according to parity, projected milk production at 305 d, and expected calving date. Within each block, cows were randomly assigned to either a conventional (CDP; 63.2 ± 2.0 d) or a short dry period (SDP; 35.2 ± 2.0 d) management in a randomized complete block design. The CDP cows were fed a far-off diet until 28 d before calving, followed by a prepartum diet, whereas SDP cows received only the prepartum diet. After calving, both groups were fed the same lactation diet. Milk yield and dry matter intake (DMI) were recorded daily and milk composition, weekly. Blood samples were taken twice a week during the first 4 wk postcalving and weekly otherwise. Omasal and ruminal samples were collected approximately 3 wk prior and 3 wk after calving. From 28 d before calving until calving, when the 2 groups of cows were fed the same prepartum diet, there was no effect of the dry period length management on DMI, plasma concentrations of ?-hydroxybutyrate, nonesterified fatty acids, and glucose and nutrient digestibility in the rumen. However, CDP cows tended to have lower ruminal pH and higher ruminal concentrations of total volatile fatty acids than SDP cows. From calving to 60 d in milk, daily DMI was higher for SDP than for CDP cows (22.3 ± 0.44 vs. 20.7 ± 0.30 kg), but milk production and milk concentrations and yields of fat, protein, and total solids were not affected by the dry period length management. After calving, body weight loss was reduced and body condition score tended to increase more rapidly for SDP than for CDP cows. Nutrient digestibility in the rumen, expressed in kilograms per day, was greater or tended to be greater for SDP cows, but differences were no longer significant when expressed per unit of nutrient ingested. The decrease in plasma nonesterified fatty acids and ?-hydroxybutyrate in SDP cows without effect on milk yield suggests an improved energy balance likely due to greater DMI. Results from the present study seem to indicate that reducing the number of diet changes before calving could facilitate ruminal adaptation to the lactation diet and improve energy balance postpartum. PMID:25306282

  14. Using time-series intervention analysis to model cow heart rate affected by programmed audio and environmental/physiological cues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This research is the first use of the Box-Jenkins time-series models to describe changes in heart rate (HR) of free-ranging crossbred cows (Bos taurus) receiving both programmed audio cues from directional virtual fencing (DVFTM) devices and non-programmed environmental/physiological cues. The DVFT...

  15. Using time-series intervention analysis to model cow heart rate affected by programmed audio and environmental/physiological

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This research is the first use of the Box-Jenkins time-series models to describe changes in heart rate (HR) of free-ranging crossbred cows (Bos taurus) receiving both programmed audio cues from directional virtual fencing (DVFTM) devices and non-programmed environmental/physiological cues. The DVFT...

  16. [Physiological processes in the mammary gland tissue of dairy cows during the dry period].

    PubMed

    Seeth, Martin tho; Hoedemaker, Martina; Krömker, Volker

    2015-01-01

    The dry period is essential for the bovine mammary gland to regenerate after the previous lactation. This period is necessary to render an appropriate milk yield during the subsequent lactation. Furthermore, the dry period allows the cure of existing infections of the mammary gland, but also bears an increased risk of new infection. The physiological processes within the bovine mammary gland can be devided in the following way: During the first days of active involution, a change in the cellular architecture is suggested, possibly caused by the high intra-alveolar pressure. Extensive histological changes affecting the capability of synthesis and secretion of milk components are also observed. During the involution, there is a loss of integrity of the mammary epithelial and various substances enter from blood into the mammary lumen. The histological and morphological changes continue during the steady state involution and the period of neolactogenesis. Hence, the composition of the secretion produced by the mammary epithelia changes markedly. Furthermore, the phases of the dry period differ in regard to the susceptibility towards intramammary infections. Therefore, it is necessary to consider the physiological processes during dry cow management. This literature survey describes the essential findings about the changes within the mammary tissue during the dry period. PMID:25876288

  17. Effects of protein supplementation frequency on physiological responses associated with reproduction in beef cows.

    PubMed

    Cappellozza, B I; Cooke, R F; Reis, M M; Marques, R S; Guarnieri Filho, T A; Perry, G A; Jump, D B; Lytle, K A; Bohnert, D W

    2015-01-01

    The objective of this experiment was to determine if frequency of protein supplementation impacts physiological responses associated with reproduction in beef cows. Fourteen nonpregnant, nonlactating beef cows were ranked by age and BW and allocated to 3 groups. Groups were assigned to a 3 × 3 Latin square design, containing 3 periods of 21 d and the following treatments: 1) soybean meal supplementation daily (D), 2) soybean meal supplementation 3 times/week (3WK), and 3) soybean meal supplementation once/week (1WK). Within each period, cows were assigned to an estrus synchronization protocol: 100 ?g of GnRH + controlled internal drug release device (CIDR) containing 1.38 g of progesterone (P4) on d 1, 25 mg of PGF2? on d 8, and CIDR removal + 100 ?g of GnRH on d 11. Grass-seed straw was offered for ad libitum consumption. Soybean meal was individually supplemented at a daily rate of 1 kg/cow (as-fed basis). Moreover, 3WK was supplemented on d 0, 2, 4, 7, 9, 11, 14, 16, and 18 whereas 1WK was supplemented on d 4, 11, and 18. Blood samples were collected from 0 (before) to 72 h after supplementation on d 11 and 18 and analyzed for plasma urea-N (PUN). Samples collected from 0 to 12 h were also analyzed for plasma glucose, insulin, and P4 (d 18 only). Uterine flushing fluid was collected concurrently with blood sampling at 28 h for pH evaluation. Liver biopsies were performed concurrently with blood sampling at 0, 4, and 28 h and analyzed for mRNA expression of carbamoyl phosphate synthetase I (CPS-I; h 28) and CYP2C19 and CYP3A4 (h 0 and 4 on d 18). Plasma urea-N concentrations were greater (P < 0.01) for 1WK vs. 3WK from 20 to 72 h and greater (P < 0.01) for 1WK vs. D from 16 to 48 h and at 72 h after supplementation (treatment × hour interaction, P < 0.01). Moreover, PUN concentrations peaked at 28 h after supplementation for 3WK and 1WK (P < 0.01) and were greater (P < 0.01) at this time for 1WK vs. 3WK and D and for 3WK vs. D. Expression of CPS-I was greater (P < 0.01) for 1WK vs. D and 3WK. Uterine flushing pH tended (P ? 0.10) to be greater for 1WK vs. 3WK and D. No treatment effects were detected (P ? 0.15) on expression of CYP2C19 and CYP3A4, plasma glucose, and P4 concentrations, whereas plasma insulin concentrations were greater (P ? 0.03) in D and 3WK vs. 1WK. Hence, decreasing frequency of protein supplementation did not reduce uterine flushing pH or plasma P4 concentrations, which are known to impact reproduction in beef cows. PMID:25412746

  18. Physiological adaptation of growth kinetics in activated sludge.

    PubMed

    Friedrich, M; Takács, I; Tränckner, J

    2015-11-15

    Physiological adaptation as it occurs in bacterial cells at variable environmental conditions influences characteristic properties of growth kinetics significantly. However, physiological adaptation to growth related parameters in activated sludge modelling is not yet recognised. Consequently these parameters are regarded to be constant. To investigate physiological adaptation in activated sludge the endogenous respiration in an aerobic degradation batch experiment and simultaneous to that the maximum possible respiration in an aerobic growth batch experiment was measured. The activated sludge samples were taken from full scale wastewater treatment plants with different sludge retention times (SRTs). It could be shown that the low SRT sludge adapts by growth optimisation (high maximum growth rate and high decay rate) to its particular environment where a high SRT sludge adapts by survival optimization (low maximum growth rate and low decay rate). Thereby, both the maximum specific growth rate and the decay rate vary in the same pattern and are strongly correlated to each other. To describe the physiological state of mixed cultures like activated sludge quantitatively a physiological state factor (PSF) is proposed as the ratio of the maximum specific growth rate and the decay rate. The PSF can be expressed as an exponential function with respect to the SRT. PMID:26284750

  19. Plasticity of physiology in Lobelia: testing for adaptation and constraint.

    PubMed

    Caruso, Christina M; Maherali, Hafiz; Sherrard, Mark

    2006-05-01

    Phenotypic plasticity is thought to be a major mechanism allowing sessile organisms such as plants to adapt to environmental heterogeneity. However, the adaptive value of many common plastic responses has not been tested by linking these responses to fitness. Even when plasticity is adaptive, costs of plasticity, such as the energy necessary to maintain regulatory pathways for plastic responses, may constrain its evolution. We used a greenhouse experiment to test whether plastic physiological responses to soil water availability (wet vs. dry conditions) were adaptive and/or costly in the congeneric wildflowers Lobelia cardinalis and L. siphilitica. Eight physiological traits related to carbon and water uptake were measured. Specific leaf area (SLA), photosynthetic rate (A), stomatal conductance (gs), and photosynthetic capacity (Amax) responded plastically to soil water availability in L. cardinalis. Plasticity in Amax was maladaptive, plasticity in A and g(s) was adaptive, and plasticity in SLA was adaptively neutral. The nature of adaptive plasticity in L. cardinalis, however, differed from previous studies. Lobelia cardinalis plants with more conservative water use, characterized by lower g(s), did not have higher fitness under drought conditions. Instead, well-watered L. cardinalis that had higher g(s) had higher fitness. Only Amax responded plastically to drought in L. siphilitica, and this response was adaptively neutral. We detected no costs of plasticity for any physiological trait in either L. cardinalis or L. siphilitica, suggesting that the evolution of plasticity in these traits would not be constrained by costs. Physiological responses to drought in plants are presumed to be adaptive, but our data suggest that much of this plasticity can be adaptively neutral or maladaptive. PMID:16817538

  20. Access to shade changes behavioral and physiological attributes of dairy cows during the hot season in the subtropics.

    PubMed

    Vizzotto, E F; Fischer, V; Thaler Neto, A; Abreu, A S; Stumpf, M T; Werncke, D; Schmidt, F A; McManus, C M

    2015-09-01

    The effect of shade on behavior and physiological attributes of grazing cows in a high altitude subtropical zone is not well established. This work aimed to investigate how social and ingestive behaviors, as well as physiological and other attributes of dairy cows such as milk production, change in a subtropical environment during the hot season either with or without free access to shade. Fourteen lactating cows were kept on pasture either with no shade or with free access to shade for 5 days and their behavior was recorded with instantaneous scan sampled every 10 min, from sunrise, 0530 h (Greenwich mean time, GMT-0200 h) to sunset, 2100 h (GMT-0200 h). Behavior traits included (1) time spent in activities such as grazing, ruminating, resting, lying, standing, walking, seeking shade and staying in the proximity to the water trough and (2) number of events such as water ingestion, aggressive interactions, as well as competition for shade and water. Physiological attributes such as heart and respiratory rates, rectal temperature, number of rumen movements, panting score, as well as milk yield, were evaluated. Time spent in behavioral activities, number of behavioral events and physiological attributes varied between groups (with and without access to shade). Cows with no shade showed increased respiratory and heart rates and panting score at 1300 h, higher values for time of permanence near the water trough, number of competition and aggression events for shade. On the other hand, they showed lower values for time spent resting while lying, ruminating while standing, seeking shade. Access to shade did not change time spent lying, standing, walking with the head up, ruminating while lying, resting while standing, as well as milk yield and number of ruminal movements. Significant interactions between access to shade and days of measurements were detected for time spent walking, ruminating, grazing, resting, number of water ingestion events, competition events near the water trough and for shade, as well as for rectal temperature and panting score measured at 1700 h. In the high altitude subtropical region, access to shade minimizes negative heat stress effects on behavior and physiological aspects of dairy cows. PMID:25994200

  1. Physiological Adaptations to Resistance Training in Prepubertal Boys

    ERIC Educational Resources Information Center

    dos Santos Cunha, Giovani; Sant'anna, Marcelo Morganti; Cadore, Eduardo Lusa; de Oliveira, Norton Luis; dos Santos, Cinara Bos; Pinto, Ronei Silveira; Reischak-Oliveira, Alvaro

    2015-01-01

    Purpose: The purpose of this study was to investigate the physiological adaptations of resistance training (RT) in prepubertal boys. Methods: Eighteen healthy boys were divided into RT (n = 9, M[subscript age] = 10.4 ± 0.5 years) and control (CTR; n = 9, M[subscript age] = 10.9 ± 0.7 years) groups. The RT group underwent a resistance training…

  2. Hormonal profiles, physiological parameters, and productive and reproductive performances of Girolando cows in the state of Ceará-Brazil

    NASA Astrophysics Data System (ADS)

    da Costa, Antônio Nélson Lima; Feitosa, José Valmir; Júnior, Péricles Afonso Montezuma; de Souza, Priscila Teixeira; de Araújo, Airton Alencar

    2015-02-01

    This study compared two breed groups of Girolando (½ Holstein ½ Gyr vs. ¾ Holstein ¼ Gyr) through analysis of physiological, productive, and reproductive parameters to determine the group best suited to rearing in a semiarid tropical climate. The experiment was conducted at the Companhia de Alimentos do Nordeste (CIALNE) farm, in the municipality of Umirim, State of Ceará, Brazil. Eighty cows were used in a 2 × 2 factorial study; 40 of each breed group were kept under an extensive system during the wet season and an intensive system during the dry season. The collection of physiological data and blood samples were obtained in the afternoon after milking. Rectal temperature (RT), surface temperature (ST), and respiratory rate (RR) were obtained for each cow after milking. Blood samples were obtained by tail vein puncture and were determined triiodothyronine (T3) and thyroxine (T4) and cortisol. The environmental parameters obtained were relative humidity (RH) and air temperature (AT), and from these, a temperature and humidity index (THI) was calculated. Pregnancy diagnosis (PD) was determined by ultrasonography 30 days after artificial insemination (AI). The milk production of each cow was recorded with automated milkings in the farm. The variables were expressed as mean and standard error, evaluated by ANOVA at 5 % probability using the Proc GLM of SAS. Chi-square test at 5 % probability was applied to data of pregnancy rate (PR) and the number of AI's to obtain pregnancy. It can be concluded that the breed group ½ Holstein ½ Gyr is most suited for farming under conditions of thermal stress.

  3. PREWEANING EFFICIENCY FOR MATURE COWS OF BREED CROSSES FROM TROPICALLY ADAPTED BOS INDICUS AND BOS TAURUS AND NON-ADAPTED BOS TAURUS BREEDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Production data were collected on mature cows, produced by mating Angus and Hereford (pooled AH) non-tropically adapted Bos taurus (NBT), Brahman (Bh) and Boran (Br) (tropically adapted Bos indicus, TBI), and Tuli (Tu, tropically adapted Bos taurus, TBT) sires by AI or natural service to Angus and H...

  4. Bennett, A. F. 1997. Adaptation and the evolution of physiological characters,pp. 3-16. In: Handbook of Physiology, Sect. 13: Comparative Physiology. W. H.

    E-print Network

    Bennett, Albert F.

    Bennett, A. F. 1997. Adaptation and the evolution of physiological characters,pp. 3-16. In. 1. Adaptation and the evolution of physiological characters A L B E R T F. B E N N E T T 1 O N T E N T S The Many meanings of "Adaptationn Criticisms of Adaptive Interpretations Alternatives

  5. Metabolic Disorders in the Transition Period Indicate that the Dairy Cows’ Ability to Adapt is Overstressed

    PubMed Central

    Sundrum, Albert

    2015-01-01

    Simple Summary Metabolic disorders are a key problem in the transition period of dairy cows and often appear before the onset of further health problems. Problems derive from difficulties animals have to adapt to large variations and disturbances occurring both outside and inside the organism. A lack of success in solving these issues may be due to predominant approaches in farm management and agricultural science, dealing with such disorders as merely negative side effects. Instead, a successful adaptation of animals to their living conditions should be seen as an important end in itself. Both farm management and agricultural sciences should support animals in their ability to cope with nutritional and metabolic challenges by employing a functional and result-driven approach. Abstract Metabolic disorders are a key problem in the transition period of dairy cows and often appear before the onset of further health problems. They mainly derive from difficulties the animals have in adapting to changes and disturbances occurring both outside and inside the organisms and due to varying gaps between nutrient supply and demand. Adaptation is a functional and target-oriented process involving the whole organism and thus cannot be narrowed down to single factors. Most problems which challenge the organisms can be solved in a number of different ways. To understand the mechanisms of adaptation, the interconnectedness of variables and the nutrient flow within a metabolic network need to be considered. Metabolic disorders indicate an overstressed ability to balance input, partitioning and output variables. Dairy cows will more easily succeed in adapting and in avoiding dysfunctional processes in the transition period when the gap between nutrient and energy demands and their supply is restricted. Dairy farms vary widely in relation to the living conditions of the animals. The complexity of nutritional and metabolic processes and their large variations on various scales contradict any attempts to predict the outcome of animals’ adaptation in a farm specific situation. Any attempts to reduce the prevalence of metabolic disorders and associated production diseases should rely on continuous and comprehensive monitoring with appropriate indicators on the farm level. Furthermore, low levels of disorders and diseases should be seen as a further significant goal which carries weight in addition to productivity goals. In the long run, low disease levels can only be expected when farmers realize that they can gain a competitive advantage over competitors with higher levels of disease. PMID:26479480

  6. Hormonal profiles, physiological parameters, and productive and reproductive performances of Girolando cows in the state of Ceará-Brazil.

    PubMed

    da Costa, Antônio Nélson Lima; Feitosa, José Valmir; Júnior, Péricles Afonso Montezuma; de Souza, Priscila Teixeira; de Araújo, Airton Alencar

    2015-02-01

    This study compared two breed groups of Girolando (½ Holstein ½ Gyr vs. ¾ Holstein ¼ Gyr) through analysis of physiological, productive, and reproductive parameters to determine the group best suited to rearing in a semiarid tropical climate. The experiment was conducted at the Companhia de Alimentos do Nordeste (CIALNE) farm, in the municipality of Umirim, State of Ceará, Brazil. Eighty cows were used in a 2?×?2 factorial study; 40 of each breed group were kept under an extensive system during the wet season and an intensive system during the dry season. The collection of physiological data and blood samples were obtained in the afternoon after milking. Rectal temperature (RT), surface temperature (ST), and respiratory rate (RR) were obtained for each cow after milking. Blood samples were obtained by tail vein puncture and were determined triiodothyronine (T3) and thyroxine (T4) and cortisol. The environmental parameters obtained were relative humidity (RH) and air temperature (AT), and from these, a temperature and humidity index (THI) was calculated. Pregnancy diagnosis (PD) was determined by ultrasonography 30 days after artificial insemination (AI). The milk production of each cow was recorded with automated milkings in the farm. The variables were expressed as mean and standard error, evaluated by ANOVA at 5% probability using the Proc GLM of SAS. Chi-square test at 5% probability was applied to data of pregnancy rate (PR) and the number of AI's to obtain pregnancy. It can be concluded that the breed group ½ Holstein ½ Gyr is most suited for farming under conditions of thermal stress. PMID:24859822

  7. Metabolic Disorders in the Transition Period Indicate that the Dairy Cows' Ability to Adapt is Overstressed.

    PubMed

    Sundrum, Albert

    2015-01-01

    Metabolic disorders are a key problem in the transition period of dairy cows and often appear before the onset of further health problems. They mainly derive from difficulties the animals have in adapting to changes and disturbances occurring both outside and inside the organisms and due to varying gaps between nutrient supply and demand. Adaptation is a functional and target-oriented process involving the whole organism and thus cannot be narrowed down to single factors. Most problems which challenge the organisms can be solved in a number of different ways. To understand the mechanisms of adaptation, the interconnectedness of variables and the nutrient flow within a metabolic network need to be considered. Metabolic disorders indicate an overstressed ability to balance input, partitioning and output variables. Dairy cows will more easily succeed in adapting and in avoiding dysfunctional processes in the transition period when the gap between nutrient and energy demands and their supply is restricted. Dairy farms vary widely in relation to the living conditions of the animals. The complexity of nutritional and metabolic processes Animals 2015, 5 979 and their large variations on various scales contradict any attempts to predict the outcome of animals' adaptation in a farm specific situation. Any attempts to reduce the prevalence of metabolic disorders and associated production diseases should rely on continuous and comprehensive monitoring with appropriate indicators on the farm level. Furthermore, low levels of disorders and diseases should be seen as a further significant goal which carries weight in addition to productivity goals. In the long run, low disease levels can only be expected when farmers realize that they can gain a competitive advantage over competitors with higher levels of disease. PMID:26479480

  8. Physiological and productive responses of multiparous lactating Holstein cows exposed to short-term cooling during severe summer conditions in an arid region of Mexico

    NASA Astrophysics Data System (ADS)

    Avendaño-Reyes, L.; Hernández-Rivera, J. A.; Álvarez-Valenzuela, F. D.; Macías-Cruz, U.; Díaz-Molina, R.; Correa-Calderón, A.; Robinson, P. H.; Fadel, J. G.

    2012-11-01

    Heat stress generates a significant economic impact for the dairy industry in arid and semi-arid regions of the world, so that heat abatement is an important issue for dairy producers. The objective of this study was to evaluate effects of two short-term cooling periods on physiological and productive status of lactating Holstein cows during hot ambient temperatures. Thirty-nine multiparous cows were blocked by milk yield and assigned to one of three treatments including: control group (C), cows cooled before milking time (0500 and 1700 h daily, 1 h cooling); AM group, cows cooled at 1000 h and before milking (2 h cooling); and AM + PM group, cows cooled at 1100, 1500 and 2200 h, as well as before milking (4 h cooling). The cooling system was placed in the holding pen which the cows were moved through for cooling. Respiratory rate, and temperatures of thurl and right flank, were lower ( P < 0.05) in cows from the AM + PM group than AM and C cows during the morning and afternoon. However, udder temperature was higher in the AM + PM group compared to AM and C groups during the afternoon, although lower than the AM group during the morning. Rectal temperature was similar in all groups. Thyroxin concentrations tended ( P < 0.10) to be lower in AM + PM relative to the AM and C groups. The AM + PM group had higher ( P < 0.05) milk production than C (18.70 vs. 17.43 kg, respectively), and AM + PM cows had a trend ( P < 0.10) to increased milk energy output vs. the C and AM groups (13.75 vs. 13.18 and 13.15 Mcal, respectively). Protein and fat in milk, body condition score, glucose, cholesterol, triglycerides and triiodothyronine were similar among the groups. Four hours of cooling with spray and fans during severe summer temperatures only modestly improved milk yield of lactating Holstein cows.

  9. Urban plant physiology: adaptation-mitigation strategies under permanent stress.

    PubMed

    Calfapietra, Carlo; Peñuelas, Josep; Niinemets, Ülo

    2015-02-01

    Urban environments that are stressful for plant function and growth will become increasingly widespread in future. In this opinion article, we define the concept of 'urban plant physiology', which focuses on plant responses and long term adaptations to urban conditions and on the capacity of urban vegetation to mitigate environmental hazards in urbanized settings such as air and soil pollution. Use of appropriate control treatments would allow for studies in urban environments to be comparable to expensive manipulative experiments. In this opinion article, we propose to couple two approaches, based either on environmental gradients or manipulated gradients, to develop the concept of urban plant physiology for assessing how single or multiple environmental factors affect the key environmental services provided by urban forests. PMID:25476199

  10. Nutrition and human physiological adaptations to space flight

    NASA Technical Reports Server (NTRS)

    Lane, H. W.; LeBlanc, A. D.; Putcha, L.; Whitson, P. A.

    1993-01-01

    Space flight provides a model for the study of healthy individuals undergoing unique stresses. This review focuses on how physiological adaptations to weightlessness may affect nutrient and food requirements in space. These adaptations include reductions in body water and plasma volume, which affect the renal and cardiovascular systems and thereby fluid and electrolyte requirements. Changes in muscle mass and function may affect requirements for energy, protein and amino acids. Changes in bone mass lead to increased urinary calcium concentrations, which may increase the risk of forming renal stones. Space motion sickness may influence putative changes in gastro-intestinal-hepatic function; neurosensory alterations may affect smell and taste. Some or all of these effects may be ameliorated through the use of specially designed dietary countermeasures.

  11. Membrane lipid unsaturation as physiological adaptation to animal longevity

    PubMed Central

    Naudí, Alba; Jové, Mariona; Ayala, Victòria; Portero-Otín, Manuel; Barja, Gustavo; Pamplona, Reinald

    2013-01-01

    The appearance of oxygen in the terrestrial atmosphere represented an important selective pressure for ancestral living organisms and contributed toward setting up the pace of evolutionary changes in structural and functional systems. The evolution of using oxygen for efficient energy production served as a driving force for the evolution of complex organisms. The redox reactions associated with its use were, however, responsible for the production of reactive species (derived from oxygen and lipids) with damaging effects due to oxidative chemical modifications of essential cellular components. Consequently, aerobic life required the emergence and selection of antioxidant defense systems. As a result, a high diversity in molecular and structural antioxidant defenses evolved. In the following paragraphs, we analyze the adaptation of biological membranes as a dynamic structural defense against reactive species evolved by animals. In particular, our goal is to describe the physiological mechanisms underlying the structural adaptation of cellular membranes to oxidative stress and to explain the meaning of this adaptive mechanism, and to review the state of the art about the link between membrane composition and longevity of animal species. PMID:24381560

  12. Physiologically responsive, mechanically adaptive polymer optical fibers for optogenetics.

    PubMed

    Jorfi, Mehdi; Voirin, Guy; Foster, E Johan; Weder, Christoph

    2014-05-15

    The capability to deliver light to specific locations within the brain using optogenetic tools has opened up new possibilities in the field of neural interfacing. In this context, optical fibers are commonly inserted into the brain to activate or mute neurons using photosensitive proteins. While chronic optogenetic stimulation studies are just beginning to emerge, knowledge gathered in connection with electrophysiological implants suggests that the mechanical mismatch of conventional optical fibers and the cortical tissue may be a significant contributor to neuroinflammatory response. Here, we present the design and fabrication of physiologically responsive, mechanically adaptive optical fibers made of poly(vinyl alcohol) (PVA) that may mitigate this problem. Produced by a one-step wet-spinning process, the fibers display a tensile storage modulus E' of ?7000??MPa in the dry state at 25°C and can thus readily be inserted into cortical tissue. Exposure to water causes a drastic reduction of E' to ?35??MPa on account of modest swelling with the water. The optical properties at 470 and 590 were comparable with losses of 0.7±0.04??dB/cm at 470 nm and 0.6±0.1??dB/cm at 590 nm in the dry state and 1.1±0.1??dB/cm at 470 nm and 0.9±0.3??dB/cm at 590 nm in the wet state. The dry end of a partially switched fiber with a length of 10 cm was coupled with a light-emitting diode with an output of 10.1 mW to deliver light with a power density of >500??mW/cm2 from the wet end, which is more than sufficient to stimulate neurons in vivo. Thus, even without a low-refractive index cladding, the physiologically responsive, mechanically adaptive optical fibers presented here appear to be a very useful new tool for future optogenetic studies. PMID:24978225

  13. Predicting animal ?18O: Accounting for diet and physiological adaptation

    NASA Astrophysics Data System (ADS)

    Kohn, Matthew J.

    1996-12-01

    Theoretical predictions and measured isotope variations indicate that diet and physiological adaptation have a significant impact on animals ?18O and cannot be ignored. A generalized model is therefore developed for the prediction of animal body water and phosphate ?18O to incorporate these factors quantitatively. Application of the model reproduces most published compositions and compositional trends for mammals and birds. A moderate dependence of animal ?18O on humidity is predicted for drought-tolerant animals, and the correlation between humidity and North American deer bone composition as corrected for local meteoric water is predicted within the scatter of the data. In contrast to an observed strong correlation between kangaroo ?18O and humidity ( ?? 18O/?h ˜ 2.5 ± 0.4‰/10% r.h.), the predicted humidity dependence is only 1.3 - 1.7‰/10% r.h., and it is inferred that drinking water in hot dry areas of Australia is enriched in 18O over rainwater. Differences in physiology and water turnover readily explain the observed differences in ?18O for several herbivore genera in East Africa, excepting antelopes. Antelope models are more sensitive to biological fractionations, and adjustments to the flux of transcutaneous water vapor within experimentally measured ranges allows their ?18O values to be matched. Models of the seasonal changes of forage composition for two regions with dissimilar climates show that significant seasonal variations in animal isotope composition are expected, and that animals with different physiologies and diets track climate differently. Analysis of different genera with disparate sensitivities to surface water and humidity will allow the most accurate quantification of past climate changes.

  14. Cyanobacteria in Antarctica: ecology, physiology and cold adaptation.

    PubMed

    Pandey, K D; Shukla, S P; Shukla, P N; Giri, D D; Singh, J S; Singh, P; Kashyap, A K

    2004-07-01

    Cyanobacterial species composition of fresh water and terrestrial ecosystems and chemical environment of water in Schirmacher Oasis in Continental Antarctica was investigated. Over 35 species of cyanobacteria were recorded. Diazotrophic species both heterocystous and unicellular contributed more than half to the count except in lake ecosystem. The species composition varied among the fresh water as well as terrestrial ecosystems. The physico-chemical analyses of water revealed its poor nurient content which might have supported the growth of diazotrophic cyanobacteria in an Antarctic environment. Among the cyanobacteria Oscillatoria, Phormidium and Nostoc commune were the dominant flora in most of the habitats. The physiological characteristics of isolated cyanobacteria strains indicated that N2-fixation, nitrate uptake, nitrate-reduction, ammonium-uptake, GS-transferase activity and photosynthesis was unaffected at low temperature (5 degrees C) which indicated low temperature adaptation for Antarctic cyanobacteria. This phenomenon was not evident in different strains of tropical origin. The temperature optima for N2-fixation for the different Antarctic cyanobacterial strains was in the range of 15-25 degrees C, nearly 10 degrees C lower than their respective reference strains of tropical origin. Similar results were obtained for cyanobacteria-moss association. The low endergonic activation energy exhibited by the above metabolic activities supported the view that cyanobacteria were adapted to Antarctic ecosystem. PMID:15559974

  15. Physiological and productive responses of multiparous lactating Holstein cows exposed to short-term cooling during severe summer conditions in an arid region of Mexico.

    PubMed

    Avendaño-Reyes, L; Hernández-Rivera, J A; Alvarez-Valenzuela, F D; Macías-Cruz, U; Díaz-Molina, R; Correa-Calderón, A; Robinson, P H; Fadel, J G

    2012-11-01

    Heat stress generates a significant economic impact for the dairy industry in arid and semi-arid regions of the world, so that heat abatement is an important issue for dairy producers. The objective of this study was to evaluate effects of two short-term cooling periods on physiological and productive status of lactating Holstein cows during hot ambient temperatures. Thirty-nine multiparous cows were blocked by milk yield and assigned to one of three treatments including: control group (C), cows cooled before milking time (0500 and 1700 h daily, 1 h cooling); AM group, cows cooled at 1000 h and before milking (2 h cooling); and AM?+?PM group, cows cooled at 1100, 1500 and 2200 h, as well as before milking (4 h cooling). The cooling system was placed in the holding pen which the cows were moved through for cooling. Respiratory rate, and temperatures of thurl and right flank, were lower (P?cows from the AM?+?PM group than AM and C cows during the morning and afternoon. However, udder temperature was higher in the AM?+?PM group compared to AM and C groups during the afternoon, although lower than the AM group during the morning. Rectal temperature was similar in all groups. Thyroxin concentrations tended (P?cows had a trend (P?cows. PMID:22116633

  16. Exercise as a countermeasure for physiological adaptation to prolonged spaceflight

    NASA Technical Reports Server (NTRS)

    Convertino, V. A.

    1996-01-01

    Exercise represents the primary countermeasure used during spaceflight to maintain or restore maximal aerobic capacity (VO2max), musculoskeletal structure, and orthostatic function. However, no single exercise or combination of prescriptions has proven entirely effective in restoring cardiovascular and musculoskeletal functions to preflight levels following prolonged spaceflight. As human spaceflight exposures increase in duration, assessment and development of various effective exercise-based protective procedures become paramount. This must involve improvement in specific countermeasure prescription as well as development of additional approaches that will allow space travelers greater flexibility and medical safety during long flights. Effective exercise prescription will be based on identification of basic physiological stimuli that maintain normal function in terrestrial gravity and understanding of how specific combinations of exercise characteristics e.g., duration, frequency, intensity, mode) can mimic these stimuli and affect the overall process of adaptation to microgravity. This can be accomplished only with greater emphasis of research on ground-based experiments. Future attention must be directed to improving exercise compliance while minimizing both crew time and the impact of the exercise on life-support resources.

  17. Resistance Training: Physiological Responses and Adaptations (Part 2 of 4).

    ERIC Educational Resources Information Center

    Fleck, Stephen J.; Kraerner, William J.

    1988-01-01

    Resistance training causes a variety of physiological reactions, including changes in muscle size, connective tissue size, and bone mineral content. This article summarizes data from a variety of studies and research. (JL)

  18. Coping with Thermal Challenges: Physiological Adaptations to Environmental Temperatures

    E-print Network

    Tattersall, Glenn

    elevated body temperatures (endothermic) or exhibit minimal internal heat production (ectothermic). In both, whereas ectothermic adaptations to temperature are best ex- emplified by the numerous mechanisms

  19. Effect of a care plan based on Roy adaptation model biological dimension on stroke patients’ physiologic adaptation level

    PubMed Central

    Alimohammadi, Nasrollah; Maleki, Bibi; Shahriari, Mohsen; Chitsaz, Ahmad

    2015-01-01

    Background: Stroke is a stressful event with several functional, physical, psychological, social, and economic problems that affect individuals’ different living balances. With coping strategies, patients try to control these problems and return to their natural life. The aim of this study is to investigate the effect of a care plan based on Roy adaptation model biological dimension on stroke patients’ physiologic adaptation level. Materials and Methods: This study is a clinical trial in which 50 patients, affected by brain stroke and being admitted in the neurology ward of Kashani and Alzahra hospitals, were randomly assigned to control and study groups in Isfahan in 2013. Roy adaptation model care plan was administered in biological dimension in the form of four sessions and phone call follow-ups for 1 month. The forms related to Roy adaptation model were completed before and after intervention in the two groups. Chi-square test and t-test were used to analyze the data through SPSS 18. Results: There was a significant difference in mean score of adaptation in physiological dimension in the study group after intervention (P < 0.001) compared to before intervention. Comparison of the mean scores of changes of adaptation in the patients affected by brain stroke in the study and control groups showed a significant increase in physiological dimension in the study group by 47.30 after intervention (P < 0.001). Conclusions: The results of study showed that Roy adaptation model biological dimension care plan can result in an increase in adaptation in patients with stroke in physiological dimension. Nurses can use this model for increasing patients’ adaptation. PMID:25878708

  20. Physiology of environmental adaptations and resource acquisition in cockroaches.

    PubMed

    Mullins, Donald E

    2015-01-01

    Cockroaches are a group of insects that evolved early in geological time. Because of their antiquity, they for the most part display generalized behavior and physiology and accordingly have frequently been used as model insects to examine physiological and biochemical mechanisms involved with water balance, nutrition, reproduction, genetics, and insecticide resistance. As a result, a considerable amount of information on these topics is available. However, there is much more to be learned by employing new protocols, microchemical analytical techniques, and molecular biology tools to explore many unanswered questions. PMID:25564743

  1. Human Adaptation to Space: Space Physiology and Countermeasures

    NASA Technical Reports Server (NTRS)

    Fogarty, Jennifer

    2009-01-01

    This viewgraph presentation reviews human physiological responses to spaceflight, and the countermeasures taken to prevent adverse effects of manned space flight. The topics include: 1) Human Spaceflight Experience; 2) Human Response to Spaceflight; 3) ISS Expeditions 1-16; 4) Countermeasure; and 5) Biomedical Data;

  2. LETTER Gut physiology mediates a trade-off between adaptation to malnutrition and susceptibility to food-borne pathogens

    E-print Network

    Kawecki, Tadeusz J.

    LETTER Gut physiology mediates a trade-off between adaptation to malnutrition and susceptibility of experimental evolution to chronic larval malnutrition became more susceptible to intestinal infection stress (malnutrition). The physiological effects of these ecological stress factors often exacerbate each

  3. Physiological adaptability: the secret of success of the internal mammary artery grafts.

    PubMed

    Singh, R N; Beg, R A; Kay, E B

    1986-03-01

    Angiographic studies in 3 patients illustrate the physiological adaptability of internal mammary artery (IMA) grafts. Intact vascular smooth muscle permits the IMA grafts to retain a flexible caliber and a blood flow dictated by myocardial demands in the distribution of the grafted coronary artery. This physiological nature may be one of the reasons for their continued patency regardless of whether they are grafted to large or small coronary arteries. Further, this adaptable behavior permits use of the IMA even if its distal lumen is smaller than that of the recipient coronary artery, provided the anastomosis can be safely performed and the demand for flow is present. PMID:3954493

  4. Phenotyping for drought adaptation in wheat using physiological traits.

    PubMed

    Monneveux, Philippe; Jing, Ruilian; Misra, Satish C

    2012-01-01

    Wheat (Triticum spp) is one of the first domesticated food crops. It represents the first source of calories (after rice) and an important source of proteins in developing countries. As a result of the Green Revolution, wheat yield sharply increased due to the use of improved varieties, irrigation, pesticides, and fertilizers. The rate of increase in world wheat production, however, slowed after 1980, except in China, India, and Pakistan. Being adapted to a wide range of moisture conditions, wheat is grown on more land area worldwide than any other crop, including in drought prone areas. In these marginal rain-fed environments where at least 60 m ha of wheat is grown, amount and distribution of rainfall are the predominant factors influencing yield variability. Intensive work has been carried out in the area of drought adaptation over the last decades. Breeding strategies for drought tolerance improvement include: definition of the target environment, choice and characterization of the testing environment, water stress management and characterization, and use of phenotyping traits with high heritability. The use of integrative traits, facilitated by the development and application of new technologies (thermal imaging, spectral reflectance, stable isotopes) is facilitating high throughput phenotyping and indirect selection, consequently favoring yield improvement in drought prone environments. PMID:23181021

  5. Adaptation to Altitude as a Vehicle for Experiential Learning of Physiology by University Undergraduates

    ERIC Educational Resources Information Center

    Weigle, David S.; Buben, Amelia; Burke, Caitlin C.; Carroll, Nels D.; Cook, Brett M.; Davis, Benjamin S.; Dubowitz, Gerald; Fisher, Rian E.; Freeman, Timothy C.; Gibbons, Stephen M.; Hansen, Hale A.; Heys, Kimberly A.; Hopkins, Brittany; Jordan, Brittany L.; McElwain, Katherine L.; Powell, Frank L.; Reinhart, Katherine E.; Robbins, Charles D.; Summers, Cameron C.; Walker, Jennifer D.; Weber, Steven S.; Weinheimer, Caroline J.

    2007-01-01

    In this article, an experiential learning activity is described in which 19 university undergraduates made experimental observations on each other to explore physiological adaptations to high altitude. Following 2 wk of didactic sessions and baseline data collection at sea level, the group ascended to a research station at 12,500-ft elevation.…

  6. Osmoregulatory Physiology of Pyloric Ceca: Regulated and Adaptive Changes in Chinook Salmon

    E-print Network

    Young, Graham

    al., '89; McCor- mick, '94). In Atlantic salmon, to which the term smolt was first appliedOsmoregulatory Physiology of Pyloric Ceca: Regulated and Adaptive Changes in Chinook Salmon PHILIP chinook salmon (Onchorhynchus tshawytscha). Transfer of salmon from freshwater to seawater (both short

  7. Physiological adaptations of Saccharomyces cerevisiae evolved for improved butanol tolerance

    PubMed Central

    2013-01-01

    Background Butanol is a chemical with potential uses as biofuel and solvent, which can be produced by microbial fermentation. However, the end product toxicity is one of the main obstacles for developing the production process irrespective of the choice of production organism. The long-term goal of the present project is to produce 2-butanol in Saccharomyces cerevisiae. Therefore, unraveling the toxicity mechanisms of solvents such as butanol and understanding the mechanisms by which tolerant strains of S. cerevisiae adapt to them would be an important contribution to the development of a bio-based butanol production process. Results A butanol tolerant S. cerevisiae was achieved through a series of sequential batch cultures with gradual increase of 2-butanol concentration. The final mutant (JBA-mut) tolerates all different alcohols tested at higher concentrations compared to the wild type (JBA-wt). Proteomics analysis of the two strains grown under mild butanol-stress revealed 46 proteins changing their expression by more than 1.5-fold in JBA-mut, 34 of which were upregulated. Strikingly, 21 out of the 34 upregulated proteins were predicted constituents of mitochondria. Among the non-mitochondrial up-regulated proteins, the minor isoform of Glycerol-3-phosphatase (Gpp2) was the most notable, since it was the only tested protein whose overexpression was found to confer butanol tolerance. Conclusion The study demonstrates several differences between the butanol tolerant mutant and the wild type. Upregulation of proteins involved in the mitochondrial ATP synthesizing machinery constituents and glycerol biosynthesis seem to be beneficial for a successful adaptation of yeast cells to butanol stress. PMID:23855998

  8. Physiological and Neural Adaptations to Eccentric Exercise: Mechanisms and Considerations for Training

    PubMed Central

    Hedayatpour, Nosratollah; Falla, Deborah

    2015-01-01

    Eccentric exercise is characterized by initial unfavorable effects such as subcellular muscle damage, pain, reduced fiber excitability, and initial muscle weakness. However, stretch combined with overload, as in eccentric contractions, is an effective stimulus for inducing physiological and neural adaptations to training. Eccentric exercise-induced adaptations include muscle hypertrophy, increased cortical activity, and changes in motor unit behavior, all of which contribute to improved muscle function. In this brief review, neuromuscular adaptations to different forms of exercise are reviewed, the positive training effects of eccentric exercise are presented, and the implications for training are considered. PMID:26543850

  9. [Altitude adaptation. Part III. Altitude acclimatization as a problem of human biology (II. Morphology, physiology, biochemistry)].

    PubMed

    Eckes, L

    1976-01-01

    The physiological mechanisms of adaptation will be reported. In a primary step of adaptation, the body reacts with immediate response, which already leads to a first classification: whether or not altitude will be tolerated by an individual. More steady biological processes follow with the same intention of balancing oxygen deficiency. They may be successful and acclimatization is possible, or they do not achieve the necessary level, i.e. that consequently developing pathological conditions of different severity lead to a next assortation of individuals with insufficient adaptability. The first state of lability can be compensated, or the intolerance will make a further stay in high altitudes impossible. No parameters exist which could allow a prognosis as to what kind of individuals will tolerate altitude or not. A different pattern of biological reaction is seen in permanent inhabitants of high altitudes who have been residing there for generations and haven't experienced conditions other than those of their special altitude in their individual lives. While ascending to higher altitudes, permanent residents also have to undergo new adaptation, as well as when descending to lower altitudes. Returning to their native environment requires reacclimatization. The mechanisms of adaptation on the organ level will be reviewed, as well as on the fluid and cellular level. All those functional and morphological mechanisms of adaptation to oxygen deficiency in high altitudes tend to maintain optimal equilibrium. Maladaptation may result. Expected genetically determined physiological alterations of adaptational value in permanent residents, which could have manifested themselves by way of "soft" selection and change of gene frequency in those high altitude populations, will be discussed. Genetical determination in such physiological parameters does not seem probable, although some pecularities such as the "blunted response" ventilation, the higher Bohr-Effect in Quenchua etc. might be interpreted in this direction. PMID:1010283

  10. Physiology

    ERIC Educational Resources Information Center

    Kay, Ian

    2008-01-01

    Underlying recent developments in health care and new treatments for disease are advances in basic medical sciences. This edition of "Webwatch" focuses on sites dealing with basic medical sciences, with particular attention given to physiology. There is a vast amount of information on the web related to physiology. The sites that are included here…

  11. Hypoxia Inducible Factor Pathway and Physiological Adaptation: A Cell Survival Pathway?

    PubMed Central

    Kumar, Hemant; Choi, Dong-Kug

    2015-01-01

    Oxygen homeostasis reflects the constant body requirement to generate energy. Hypoxia (0.1–1% O2), physioxia or physoxia (?1–13%), and normoxia (?20%) are terms used to define oxygen concentration in the cellular environment. A decrease in oxygen (hypoxia) or excess oxygen (hyperoxia) could be deleterious for cellular adaptation and survival. Hypoxia can occur under both physiological (e.g., exercise, embryonic development, underwater diving, or high altitude) and pathological conditions (e.g., inflammation, solid tumor formation, lung disease, or myocardial infarction). Hypoxia plays a key role in the pathophysiology of heart disease, cancers, stroke, and other causes of mortality. Hypoxia inducible factor(s) (HIFs) are key oxygen sensors that mediate the ability of the cell to cope with decreased oxygen tension. These transcription factors regulate cellular adaptation to hypoxia and protect cells by responding acutely and inducing production of endogenous metabolites and proteins to promptly regulate metabolic pathways. Here, we review the role of the HIF pathway as a metabolic adaptation pathway and how this pathway plays a role in cell survival. We emphasize the roles of the HIF pathway in physiological adaptation, cell death, pH regulation, and adaptation during exercise. PMID:26491231

  12. Predicting organismal vulnerability to climate warming: roles of behaviour, physiology and adaptation

    PubMed Central

    Huey, Raymond B.; Kearney, Michael R.; Krockenberger, Andrew; Holtum, Joseph A. M.; Jess, Mellissa; Williams, Stephen E.

    2012-01-01

    A recently developed integrative framework proposes that the vulnerability of a species to environmental change depends on the species' exposure and sensitivity to environmental change, its resilience to perturbations and its potential to adapt to change. These vulnerability criteria require behavioural, physiological and genetic data. With this information in hand, biologists can predict organisms most at risk from environmental change. Biologists and managers can then target organisms and habitats most at risk. Unfortunately, the required data (e.g. optimal physiological temperatures) are rarely available. Here, we evaluate the reliability of potential proxies (e.g. critical temperatures) that are often available for some groups. Several proxies for ectotherms are promising, but analogous ones for endotherms are lacking. We also develop a simple graphical model of how behavioural thermoregulation, acclimation and adaptation may interact to influence vulnerability over time. After considering this model together with the proxies available for physiological sensitivity to climate change, we conclude that ectotherms sharing vulnerability traits seem concentrated in lowland tropical forests. Their vulnerability may be exacerbated by negative biotic interactions. Whether tropical forest (or other) species can adapt to warming environments is unclear, as genetic and selective data are scant. Nevertheless, the prospects for tropical forest ectotherms appear grim. PMID:22566674

  13. Boldness behavior and stress physiology in a novel urban environment suggest rapid correlated evolutionary adaptation

    PubMed Central

    Cardoso, Gonçalo C.; Whittaker, Danielle J.; Campbell-Nelson, Samuel; Robertson, Kyle W.; Ketterson, Ellen D.

    2012-01-01

    Novel or changing environments expose animals to diverse stressors that likely require coordinated hormonal and behavioral adaptations. Predicted adaptations to urban environments include attenuated physiological responses to stressors and bolder exploratory behaviors, but few studies to date have evaluated the impact of urban life on codivergence of these hormonal and behavioral traits in natural systems. Here, we demonstrate rapid adaptive shifts in both stress physiology and correlated boldness behaviors in a songbird, the dark-eyed junco, following its colonization of a novel urban environment. We compared elevation in corticosterone (CORT) in response to handling and flight initiation distances in birds from a recently established urban population in San Diego, California to birds from a nearby wildland population in the species' ancestral montane breeding range. We also measured CORT and exploratory behavior in birds raised from early life in a captive common garden study. We found persistent population differences for both reduced CORT responses and bolder exploratory behavior in birds from the colonist population, as well as significant negative covariation between maximum CORT and exploratory behavior. Although early developmental effects cannot be ruled out, these results suggest contemporary adaptive evolution of correlated hormonal and behavioral traits associated with colonization of an urban habitat. PMID:22936840

  14. Common-garden studies on adaptive radiation of photosynthetic physiology among Hawaiian lobeliads.

    PubMed

    Givnish, Thomas J; Montgomery, Rebecca A

    2014-03-22

    Species in an adaptive radiation often occupy different habitats so that individuals of each species develop under different conditions. Showing that a radiation is adaptive thus requires evidence that taxa have diverged genetically and that each has an ecological advantage in using particular habitats or resources, taking into account both phenotypic plasticity and phylogenetic relationships among species. Here, we use a common-garden experiment to show that representative species of Hawaiian lobeliads have diverged adaptively in their leaf-level photosynthetic light responses. Across species, plants genetically shifted their photosynthetic physiology with native light regime in accord with theoretical predictions and exhibited adaptive crossover in net carbon gain-that is, species native to a given light regime outperformed others only under conditions similar to those they occupy in the field, with the rank order of species based on photosynthesis per unit leaf mass changing with light level. These findings make a powerful case for adaptation of photosynthetic light responses to native light regimes and, combined with our earlier field studies, provide the strongest demonstration to date for the evolution of divergent adaptations for energy capture in any group of closely related plants. PMID:24478303

  15. Eco-physiological adaptation shapes the response of calcifying algae to nutrient limitation

    PubMed Central

    Šupraha, Luka; Gerecht, Andrea C.; Probert, Ian; Henderiks, Jorijntje

    2015-01-01

    The steady increase in global ocean temperature will most likely lead to nutrient limitation in the photic zone. This will impact the physiology of marine algae, including the globally important calcifying coccolithophores. Understanding their adaptive patterns is essential for modelling carbon production in a low-nutrient ocean. We investigated the physiology of Helicosphaera carteri, a representative of the abundant but under-investigated flagellated functional group of coccolithophores. Two strains isolated from contrasting nutrient regimes (South Atlantic and Mediterranean Sea) were grown in phosphorus-replete and phosphorus-limited batch cultures. While growing exponentially in a phosphorus-replete medium, the Mediterranean strain exhibited on average 24% lower growth rate, 36% larger coccosphere volume and 21% lower particulate inorganic carbon (PIC) production than the Atlantic strain. Under phosphorus limitation, the same strain was capable of reaching a 2.6 times higher cell density than the Atlantic strain due to lower phosphorus requirements. These results suggest that local physiological adaptation can define the performance of this species under nutrient limitation. PMID:26560531

  16. King of the mountains: Tibetan and Sherpa physiological adaptations for life at high altitude.

    PubMed

    Gilbert-Kawai, Edward T; Milledge, James S; Grocott, Michael P W; Martin, Daniel S

    2014-11-01

    Anecdotal evidence surrounding Tibetans' and Sherpas' exceptional tolerance to hypobaric hypoxia has been recorded since the beginning of high-altitude exploration. These populations have successfully lived and reproduced at high altitude for hundreds of generations with hypoxia as a constant evolutionary pressure. Consequently, they are likely to have undergone natural selection toward a genotype (and phenotype) tending to offer beneficial adaptation to sustained hypoxia. With the advent of translational human hypoxic research, in which genotype/phenotype studies of healthy individuals at high altitude may be of benefit to hypoxemic critically ill patients in a hospital setting, high-altitude natives may provide a valuable and intriguing model. The aim of this review is to provide a comprehensive summary of the scientific literature encompassing Tibetan and Sherpa physiological adaptations to a high-altitude residence. The review demonstrates the extent to which evolutionary pressure has refined the physiology of this high-altitude population. Furthermore, although many physiological differences between highlanders and lowlanders have been found, it also suggests many more potential avenues of investigation. PMID:25362633

  17. Eco-physiological adaptation shapes the response of calcifying algae to nutrient limitation

    NASA Astrophysics Data System (ADS)

    Šupraha, Luka; Gerecht, Andrea C.; Probert, Ian; Henderiks, Jorijntje

    2015-11-01

    The steady increase in global ocean temperature will most likely lead to nutrient limitation in the photic zone. This will impact the physiology of marine algae, including the globally important calcifying coccolithophores. Understanding their adaptive patterns is essential for modelling carbon production in a low-nutrient ocean. We investigated the physiology of Helicosphaera carteri, a representative of the abundant but under-investigated flagellated functional group of coccolithophores. Two strains isolated from contrasting nutrient regimes (South Atlantic and Mediterranean Sea) were grown in phosphorus-replete and phosphorus-limited batch cultures. While growing exponentially in a phosphorus-replete medium, the Mediterranean strain exhibited on average 24% lower growth rate, 36% larger coccosphere volume and 21% lower particulate inorganic carbon (PIC) production than the Atlantic strain. Under phosphorus limitation, the same strain was capable of reaching a 2.6 times higher cell density than the Atlantic strain due to lower phosphorus requirements. These results suggest that local physiological adaptation can define the performance of this species under nutrient limitation.

  18. Eco-physiological adaptation shapes the response of calcifying algae to nutrient limitation.

    PubMed

    Šupraha, Luka; Gerecht, Andrea C; Probert, Ian; Henderiks, Jorijntje

    2015-01-01

    The steady increase in global ocean temperature will most likely lead to nutrient limitation in the photic zone. This will impact the physiology of marine algae, including the globally important calcifying coccolithophores. Understanding their adaptive patterns is essential for modelling carbon production in a low-nutrient ocean. We investigated the physiology of Helicosphaera carteri, a representative of the abundant but under-investigated flagellated functional group of coccolithophores. Two strains isolated from contrasting nutrient regimes (South Atlantic and Mediterranean Sea) were grown in phosphorus-replete and phosphorus-limited batch cultures. While growing exponentially in a phosphorus-replete medium, the Mediterranean strain exhibited on average 24% lower growth rate, 36% larger coccosphere volume and 21% lower particulate inorganic carbon (PIC) production than the Atlantic strain. Under phosphorus limitation, the same strain was capable of reaching a 2.6 times higher cell density than the Atlantic strain due to lower phosphorus requirements. These results suggest that local physiological adaptation can define the performance of this species under nutrient limitation. PMID:26560531

  19. Match and mismatch: conservation physiology, nutritional ecology and the timescales of biological adaptation

    PubMed Central

    Raubenheimer, David; Simpson, Stephen J.; Tait, Alice H.

    2012-01-01

    Conservation physiology (CP) and nutritional ecology (NE) are both integrative sciences that share the fundamental aim of understanding the patterns, mechanisms and consequences of animal responses to changing environments. Here, we explore the high-level similarities and differences between CP and NE, identifying as central themes to both fields the multiple timescales over which animals adapt (and fail to adapt) to their environments, and the need for integrative models to study these processes. At one extreme are the short-term regulatory responses that modulate the state of animals in relation to the environment, which are variously considered under the concepts of homeostasis, homeorhesis, enantiostasis, heterostasis and allostasis. In the longer term are developmental responses, including phenotypic plasticity and transgenerational effects mediated by non-genomic influences such as parental physiology, epigenetic effects and cultural learning. Over a longer timescale still are the cumulative genetic changes that take place in Darwinian evolution. We present examples showing how the adaptive responses of animals across these timescales have been represented in an integrative framework from NE, the geometric framework (GF) for nutrition, and close with an illustration of how GF can be applied to the central issue in CP, animal conservation. PMID:22566672

  20. Global Transcriptional, Physiological, and Metabolite Analyses of the Responses of Desulfovibrio vulgaris Hildenborough to Salt Adaptation ? †

    PubMed Central

    He, Zhili; Zhou, Aifen; Baidoo, Edward; He, Qiang; Joachimiak, Marcin P.; Benke, Peter; Phan, Richard; Mukhopadhyay, Aindrila; Hemme, Christopher L.; Huang, Katherine; Alm, Eric J.; Fields, Matthew W.; Wall, Judy; Stahl, David; Hazen, Terry C.; Keasling, Jay D.; Arkin, Adam P.; Zhou, Jizhong

    2010-01-01

    The response of Desulfovibrio vulgaris Hildenborough to salt adaptation (long-term NaCl exposure) was examined by performing physiological, global transcriptional, and metabolite analyses. Salt adaptation was reflected by increased expression of genes involved in amino acid biosynthesis and transport, electron transfer, hydrogen oxidation, and general stress responses (e.g., heat shock proteins, phage shock proteins, and oxidative stress response proteins). The expression of genes involved in carbon metabolism, cell growth, and phage structures was decreased. Transcriptome profiles of D. vulgaris responses to salt adaptation were compared with transcriptome profiles of D. vulgaris responses to salt shock (short-term NaCl exposure). Metabolite assays showed that glutamate and alanine accumulated under salt adaptation conditions, suggesting that these amino acids may be used as osmoprotectants in D. vulgaris. Addition of amino acids (glutamate, alanine, and tryptophan) or yeast extract to the growth medium relieved salt-related growth inhibition. A conceptual model that links the observed results to currently available knowledge is proposed to increase our understanding of the mechanisms of D. vulgaris adaptation to elevated NaCl levels. PMID:20038696

  1. Global transcriptional, physiological and metabolite analyses of Desulfovibrio vulgaris Hildenborough responses to salt adaptation

    SciTech Connect

    He, Z.; Zhou, A.; Baidoo, E.; He, Q.; Joachimiak, M. P.; Benke, P.; Phan, R.; Mukhopadhyay, A.; Hemme, C.L.; Huang, K.; Alm, E.J.; Fields, M.W.; Wall, J.; Stahl, D.; Hazen, T.C.; Keasling, J.D.; Arkin, A.P.; Zhou, J.

    2009-12-01

    The response of Desulfovibrio vulgaris Hildenborough to salt adaptation (long-term NaCl exposure) was examined by physiological, global transcriptional, and metabolite analyses. The growth of D. vulgaris was inhibited by high levels of NaCl, and the growth inhibition could be relieved by the addition of exogenous amino acids (e.g., glutamate, alanine, tryptophan) or yeast extract. Salt adaptation induced the expression of genes involved in amino acid biosynthesis and transport, electron transfer, hydrogen oxidation, and general stress responses (e.g., heat shock proteins, phage shock proteins, and oxidative stress response proteins). Genes involved in carbon metabolism, cell motility, and phage structures were repressed. Comparison of transcriptomic profiles of D. vulgaris responses to salt adaptation with those of salt shock (short-term NaCl exposure) showed some similarity as well as a significant difference. Metabolite assays showed that glutamate and alanine were accumulated under salt adaptation, suggesting that they may be used as osmoprotectants in D. vulgaris. A conceptual model is proposed to link the observed results to currently available knowledge for further understanding the mechanisms of D. vulgaris adaptation to elevated NaCl.

  2. What Has Natural Variation Taught Us about Plant Development, Physiology, and Adaptation?

    PubMed Central

    Alonso-Blanco, Carlos; Aarts, Mark G.M.; Bentsink, Leonie; Keurentjes, Joost J.B.; Reymond, Matthieu; Vreugdenhil, Dick; Koornneef, Maarten

    2009-01-01

    Nearly 100 genes and functional polymorphisms underlying natural variation in plant development and physiology have been identified. In crop plants, these include genes involved in domestication traits, such as those related to plant architecture, fruit and seed structure and morphology, as well as yield and quality traits improved by subsequent crop breeding. In wild plants, comparable traits have been dissected mainly in Arabidopsis thaliana. In this review, we discuss the major contributions of the analysis of natural variation to our understanding of plant development and physiology, focusing in particular on the timing of germination and flowering, plant growth and morphology, primary metabolism, and mineral accumulation. Overall, functional polymorphisms appear in all types of genes and gene regions, and they may have multiple mutational causes. However, understanding this diversity in relation to adaptation and environmental variation is a challenge for which tools are now available. PMID:19574434

  3. Adaptation of plasma membrane amino acid transport mechanisms to physiological demands.

    PubMed

    Bröer, Stefan

    2002-07-01

    The molecular identification of almost all physiologically characterized amino acid transporters in recent years has facilitated the functional analysis of this important class of transport proteins. The picture that emerges from these studies is that antiport is the prevalent mode of amino acid transport rather than a combination of uniporters and cotransporters. Mainly neurotransmitters and osmolytes are transported by complex cotransport mechanisms that allow a high intracellular accumulation. Antiport mechanisms almost invariably include the nonessential amino acids alanine and glutamine, which are used as exchange substrates. The intracellular level of both amino acids is well regulated by Na(+)/amino acid cotransporters. Transport mechanisms are not conserved within families and may change with mutation of even a single amino acid residue in the transport protein. Thus transport mechanisms are easily adapted to physiological demands during evolution. PMID:12136264

  4. Reliable emotion recognition system based on dynamic adaptive fusion of forehead biopotentials and physiological signals.

    PubMed

    Khezri, Mahdi; Firoozabadi, Mohammad; Sharafat, Ahmad Reza

    2015-11-01

    In this study, we proposed a new adaptive method for fusing multiple emotional modalities to improve the performance of the emotion recognition system. Three-channel forehead biosignals along with peripheral physiological measurements (blood volume pressure, skin conductance, and interbeat intervals) were utilized as emotional modalities. Six basic emotions, i.e., anger, sadness, fear, disgust, happiness, and surprise were elicited by displaying preselected video clips for each of the 25 participants in the experiment; the physiological signals were collected simultaneously. In our multimodal emotion recognition system, recorded signals with the formation of several classification units identified the emotions independently. Then the results were fused using the adaptive weighted linear model to produce the final result. Each classification unit is assigned a weight that is determined dynamically by considering the performance of the units during the testing phase and the training phase results. This dynamic weighting scheme enables the emotion recognition system to adapt itself to each new user. The results showed that the suggested method outperformed conventional fusion of the features and classification units using the majority voting method. In addition, a considerable improvement, compared to the systems that used the static weighting schemes for fusing classification units, was also shown. Using support vector machine (SVM) and k-nearest neighbors (KNN) classifiers, the overall classification accuracies of 84.7% and 80% were obtained in identifying the emotions, respectively. In addition, applying the forehead or physiological signals in the proposed scheme indicates that designing a reliable emotion recognition system is feasible without the need for additional emotional modalities. PMID:26253158

  5. Local Adaptation to Altitude Underlies Divergent Thermal Physiology in Tropical Killifishes of the Genus Aphyosemion

    PubMed Central

    McKenzie, David J.; Estivales, Guillan; Svendsen, Jon C.; Steffensen, John F.; Agnèse, Jean-François

    2013-01-01

    In watersheds of equatorial West Africa, monophyletic groups of killifish species (genus Aphyosemion) occur in discrete altitudinal ranges, low altitude species (LA, sea level to ?350 m) or high altitude species (HA, 350 to 900 m). We investigated the hypothesis that local adaptation to altitude by the LA and HA species would be revealed as divergent effects of temperature on their physiological energetics. Two species from each group (mass ?350 mg) were acclimated to 19, 25 and 28°C, with 19 and 28°C estimated to be outside the thermal envelope for LA or HA, respectively, in the wild. Wild-caught animals (F0 generation) were compared with animals raised in captivity at 25°C (F1 generation) to investigate the contribution of adaptation versus plasticity. Temperature significantly increased routine metabolic rate in all groups and generations. However, LA and HA species differed in the effects of temperature on their ability to process a meal. At 25°C, the specific dynamic action (SDA) response was completed within 8 h in all groups, but acclimation to temperatures beyond the thermal envelope caused profound declines in SDA performance. At 19°C, the LA required ?14 h to complete the SDA, whereas the HA required only ?7 h. The opposite effect was observed at 28°C. This effect was evident in both F0 and F1. Reaction norms for effects of temperature on SDA therefore revealed a trade-off, with superior performance at warmer temperatures by LA being associated with inferior performance at cooler temperatures, and vice-versa in HA. The data indicate that divergent physiological responses to temperature in the LA and HA species reflect local adaptation to the thermal regime in their habitat, and that local adaptation to one thermal environment trades off against performance in another. PMID:23349857

  6. Adaptive divergence in a scleractinian coral: physiological adaptation of Seriatopora hystrix to shallow and deep reef habitats

    PubMed Central

    2011-01-01

    Background Divergent natural selection across environmental gradients has been acknowledged as a major driver of population and species divergence, however its role in the diversification of scleractinian corals remains poorly understood. Recently, it was demonstrated that the brooding coral Seriatopora hystrix and its algal endosymbionts (Symbiodinium) are genetically partitioned across reef environments (0-30 m) on the far northern Great Barrier Reef. Here, we explore the potential mechanisms underlying this differentiation and assess the stability of host-symbiont associations through a reciprocal transplantation experiment across habitats ('Back Reef', 'Upper Slope' and 'Deep Slope'), in combination with molecular (mtDNA and ITS2-DGGE) and photo-physiological analyses (respirometry and HPLC). Results The highest survival rates were observed for native transplants (measured 14 months after transplantation), indicating differential selective pressures between habitats. Host-symbiont assemblages remained stable during the experimental duration, demonstrating that the ability to "shuffle" or "switch" symbionts is restricted in S. hystrix. Photo-physiological differences were observed between transplants originating from the shallow and deep habitats, with indirect evidence of an increased heterotrophic capacity in native deep-water transplants (from the 'Deep Slope' habitat). Similar photo-acclimatisation potential was observed between transplants originating from the two shallow habitats ('Back Reef' and 'Upper Slope'), highlighting that their genetic segregation over depth may be due to other, non-photo-physiological traits under selection. Conclusions This study confirms that the observed habitat partitioning of S. hystrix (and associated Symbiodinium) is reflective of adaptive divergence along a depth gradient. Gene flow appears to be reduced due to divergent selection, highlighting the potential role of ecological mechanisms, in addition to physical dispersal barriers, in the diversification of scleractinian corals and their associated Symbiodinium. PMID:22004364

  7. Physiological adaptations of yeasts living in cold environments and their potential applications.

    PubMed

    Alcaíno, Jennifer; Cifuentes, Víctor; Baeza, Marcelo

    2015-10-01

    Yeasts, widely distributed across the Earth, have successfully colonized cold environments despite their adverse conditions for life. Lower eukaryotes play important ecological roles, contributing to nutrient recycling and organic matter mineralization. Yeasts have developed physiological adaptations to optimize their metabolism in low-temperature environments, which affect the rates of biochemical reactions and membrane fluidity. Decreased saturation of fatty acids helps maintain membrane fluidity at low temperatures and the production of compounds that inhibit ice crystallization, such as antifreeze proteins, helps microorganisms survive at temperatures around the freezing point of water. Furthermore, the production of hydrolytic extracellular enzymes active at low temperatures allows consumption of available carbon sources. Beyond their ecological importance, interest in psychrophilic yeasts has increased because of their biotechnological potential and industrial uses. Long-chain polyunsaturated fatty acids have beneficial effects on human health, and antifreeze proteins are attractive for food industries to maintain texture in food preserved at low temperatures. Furthermore, extracellular cold-active enzymes display unusual substrate specificities with higher catalytic efficiency at low temperatures than their mesophilic counterparts, making them attractive for industrial processes requiring high enzymatic activity at low temperatures. In this minireview, we describe the physiological adaptations of several psychrophilic yeasts and their possible biotechnological applications. PMID:26160010

  8. Adaptive Physiological Response to Perceived Scarcity as a Mechanism of Sensory Modulation of Life Span.

    PubMed

    Waterson, Michael J; Chan, Tammy P; Pletcher, Scott D

    2015-09-01

    Chemosensation is a potent modulator of organismal physiology and longevity. In Drosophila, loss of recognition of diverse tastants has significant and bidirectional life-span effects. Recently published results revealed that when flies were unable to taste water, they increased its internal generation, which may have subsequently altered life span. To determine whether similar adaptive responses occur in other contexts, we explored the impact of sensory deficiency of other metabolically important molecules. Trehalose is a major circulating carbohydrate in the fly that is recognized by the gustatory receptor Gr5a. Gr5a mutant flies are short lived, and we found that they specifically increased whole-body and circulating levels of trehalose, but not other carbohydrates, likely through upregulation of de novo synthesis. dILP2 transcript levels were increased in Gr5a mutants, a possible response intended to reduce hypertrehalosemia, and likely a contributing factor to their reduced life span. Together, these data suggest that compensatory physiological responses to perceived environmental scarcity, which are designed to alleviate the ostensive shortage, may be a common outcome of sensory manipulation. We suggest that future investigations into the mechanisms underlying sensory modulation of aging may benefit by focusing on direct or indirect consequences of physiological changes that are designed to correct perceived disparity with the environment. PMID:25878032

  9. Oral and physiological paleohealth in cold adapted peoples: Northeast Asia, Hokkaido.

    PubMed

    Oxenham, Marc F; Matsumura, Hirofumi

    2008-01-01

    This paper examines variables useful in reconstructing oral (caries, antemortem tooth loss, alveolar defects) and physiological (cribra orbitalia, linear enamel hypoplasia) well-being in two bioarchaeological assemblages from Hokkaido, Japan: Okhotsk (n = 37 individuals) and Jomon (n = 60). Findings are compared and contrasted with each other, with published series from Honshu Japan, and samples from climatically near-equivalent Alaska. It was found that more meaningful comparisons of Hokkaido paleohealth could be made with Alaskan material, rather than the more southerly Jomon. Results were ambiguous with respect to physiological well-being. Low levels of LEH in the cold-adapted samples suggest operating in arctic and subarctic environments with marine-based subsistence regimes is not physiologically expensive. However, the relatively high levels of cribra orbitalia in Hokkaido, relative to Alaska, suggest the picture is not straightforward: the reasons for elevated cribra orbitalia in Hokkaido are unclear. The subarctic and arctic samples formed three broadly similar groupings in terms of oral health profiles: (1) Aleuts and Eskimo; (2) Ipiutak and Tigara; (3) Hokkaido Jomon, Okhotsk, and Kodiak Island. Differences between these groupings could be explained with a combination of sample demographics and subsistence orientations. The extremely high frequency of caries in one sample, caribou hunting Ipiutak, may have been influenced by factors such as low levels of dietary magnesium and potentially cariogenic foodstuffs, such as preparations of caribou stomach contents. It was concluded that oral health profiles are potentially sensitive to differences in subsistence strategies among cold-adapted hunter-gatherers, although they lack predictive value. PMID:17786996

  10. Antepartal insulin-like growth factor concentrations indicating differences in the metabolic adaptive capacity of dairy cows

    PubMed Central

    Holzhausen, Lars; Araujo, Marcelo Gil; Heppelmann, Maike; Sipka, Anja; Pfarrer, Chistiane; Schuberth, Hans-Joachim; Bollwein, Heinrich

    2014-01-01

    Cows with different Insulin-like Growth Factor-I (IGF-I) concentrations showed comparable expression levels of hepatic growth hormone receptor (GHR). Suppressor of cytokine signaling 2 (SOCS2), could be responsible for additional inhibition of the GHR signal cascade. The aims were to monitor cows with high or low antepartal IGF-I concentrations (IGF-Ihigh or IGF-Ilow), evaluate the interrelationships of endocrine endpoints, and measure hepatic SOCS2 expression. Dairy cows (n = 20) were selected (240 to 254 days after artificial insemination (AI)). Blood samples were drawn daily (day -17 until calving) and IGF-I, GH, insulin, thyroid hormones, estradiol, and progesterone concentrations were measured. Liver biopsies were taken (day 264 ± 1 after AI and postpartum) to measure mRNA expression (IGF-I, IGFBP-2, IGFBP-3, IGFBP-4, acid labile subunit (ALS), SOCS2, deiodinase1, GHR1A). IGF-I concentrations in the two groups were different (p < 0.0001). However, GH concentrations and GHR1A mRNA expression were comparable (p > 0.05). Thyroxine levels and ALS expression were higher in the IGF-Ihigh cows compared to IGF-Ilow cows. Estradiol concentration tended to be greater in the IGF-Ilow group (p = 0.06). It was hypothesized that low IGF-I levels are associated with enhanced SOCS2 expression although this could not be decisively confirmed by the present study. PMID:24962413

  11. High sustained +Gz acceleration: physiological adaptation to high-G tolerance

    NASA Technical Reports Server (NTRS)

    Convertino, V. A.

    1998-01-01

    Since the early 1940s, a significant volume of research has been conducted in an effort to describe the impact of acute exposures to high-G acceleration on cardiovascular mechanisms responsible to maintaining cerebral perfusion and conscious in high performance aircraft pilots during aerial combat maneuvers. The value of understanding hemodynamic characteristics that underlie G-induced loss of consciousness has been instrumental in the evolution of optimal technology development (e.g., G-suits, positive pressure breathing, COMBAT EDGE, etc.) and pilot training (e.g., anti-G straining maneuvers). Although the emphasis of research has been placed on the development of protection against acute high +Gz acceleration effects, recent observations suggest that adaptation of cardiovascular mechanism associated with blood pressure regulation may contribute to a protective 'G-training' effect. Regular training at high G enhances G tolerance in humans, rats, guinea pigs, and dogs while prolonged layoff from exposure in high G profiles (G-layoff) can result in reduced G endurance. It seems probable that adaptations in physiological functions following chronically-repeated high G exposure (G training) or G-layoff could have significant impacts on performance during sustained high-G acceleration since protective technology such as G-suits and anit-G straining maneuvers are applied consistently during these periods of training. The purpose of this paper is to present a review of new data from three experiments that support the notion that repeated exposure on a regular basis to high sustained +Gz acceleration induces significant physiological adaptations which are associated with improved blood pressure regulation and subsequent protection of cerebral perfusion during orthostatic challenges.

  12. Genetic variance and covariance for physiological traits in Lobelia: are there constraints on adaptive evolution?

    PubMed

    Caruso, Christina M; Maherali, Hafiz; Mikulyuk, Alison; Carlson, Kjarstin; Jackson, Robert B

    2005-04-01

    Physiological traits that control the uptake of carbon dioxide and loss of water are key determinants of plant growth and reproduction. Variation in these traits is often correlated with environmental gradients of water, light, and nutrients, suggesting that natural selection is the primary evolutionary mechanism responsible for physiological diversification. Responses to selection, however, can be constrained by the amount of standing genetic variation for physiological traits and genetic correlations between these traits. To examine the potential for constraint on adaptive evolution, we estimated the quantitative genetic basis of physiological trait variation in one population of each of two closely related species (Lobelia siphilitica and L. cardinalis). Restricted maximum likelihood analyses of greenhouse-grown half-sib families were used to estimate genetic variances and covariances for seven traits associated with carbon and water relations. We detected significant genetic variation for all traits in L. siphilitica, suggesting that carbon-gain and water-use traits could evolve in response to natural selection in this population. In particular, narrow-sense heritabilities for photosynthetic rate (A), stomatal conductance (gs), and water-use efficiency (WUE) in our L. siphilitica population were high relative to previous studies in other species. Although there was significant narrow-sense heritability for A in L. cardinalis, we detected little genetic variation for traits associated with water use (gs and WUE), suggesting that our population of this species may be unable to adapt to drier environments. Despite being tightly linked functionally, the genetic correlation between A and gs was not strong and significant in either population. Therefore, our L. siphilitica population would not be genetically constrained from evolving high A (and thus fixing more carbon for growth and reproduction) while also decreasing gs to limit water loss. However, a significant negative genetic correlation existed between WUE and plant size in L. siphilitica, suggesting that high WUE may be negatively associated with high fecundity. In contrast, our results suggest that any constraints on the evolution of photosynthetic and stomatal traits of L. cardinalis are caused primarily by a lack of genetic variation, rather than by genetic correlations between these functionally related traits. PMID:15926692

  13. Seasonal variation in coat characteristics, tick loads, cortisol levels, some physiological parameters and temperature humidity index on Nguni cows raised in low- and high-input farms

    NASA Astrophysics Data System (ADS)

    Katiyatiya, C. L. F.; Muchenje, V.; Mushunje, A.

    2014-08-01

    Seasonal variations in hair length, tick loads, cortisol levels, haematological parameters (HP) and temperature humidity index (THI) in Nguni cows of different colours raised in two low-input farms, and a commercial stud was determined. The sites were chosen based on their production systems, climatic characteristics and geographical locations. Zazulwana and Komga are low-input, humid-coastal areas, while Honeydale is a high-input, dry-inland Nguni stud farm. A total of 103 cows, grouped according to parity, location and coat colour, were used in the study. The effects of location, coat colour, hair length and season were used to determine tick loads on different body parts, cortisol levels and HP in blood from Nguni cows. Highest tick loads were recorded under the tail and the lowest on the head of each of the animals (P < 0.05). Zazulwana cows recorded the highest tick loads under the tails of all the cows used in the study from the three farms (P < 0.05). High tick loads were recorded for cows with long hairs. Hair lengths were longest during the winter season in the coastal areas of Zazulwana and Honeydale (P < 0.05). White and brown-white patched cows had significantly longer (P < 0.05) hair strands than those having a combination of red, black and white colour. Cortisol and THI were significantly lower (P < 0.05) in summer season. Red blood cells, haematoglobin, haematocrit, mean cell volumes, white blood cells, neutrophils, lymphocytes, eosinophils and basophils were significantly different (P < 0.05) as some associated with age across all seasons and correlated to THI. It was concluded that the location, coat colour and season had effects on hair length, cortisol levels, THI, HP and tick loads on different body parts and heat stress in Nguni cows.

  14. Seasonal variation in coat characteristics, tick loads, cortisol levels, some physiological parameters and temperature humidity index on Nguni cows raised in low- and high-input farms

    NASA Astrophysics Data System (ADS)

    Katiyatiya, C. L. F.; Muchenje, V.; Mushunje, A.

    2015-06-01

    Seasonal variations in hair length, tick loads, cortisol levels, haematological parameters (HP) and temperature humidity index (THI) in Nguni cows of different colours raised in two low-input farms, and a commercial stud was determined. The sites were chosen based on their production systems, climatic characteristics and geographical locations. Zazulwana and Komga are low-input, humid-coastal areas, while Honeydale is a high-input, dry-inland Nguni stud farm. A total of 103 cows, grouped according to parity, location and coat colour, were used in the study. The effects of location, coat colour, hair length and season were used to determine tick loads on different body parts, cortisol levels and HP in blood from Nguni cows. Highest tick loads were recorded under the tail and the lowest on the head of each of the animals ( P < 0.05). Zazulwana cows recorded the highest tick loads under the tails of all the cows used in the study from the three farms ( P < 0.05). High tick loads were recorded for cows with long hairs. Hair lengths were longest during the winter season in the coastal areas of Zazulwana and Honeydale ( P < 0.05). White and brown-white patched cows had significantly longer ( P < 0.05) hair strands than those having a combination of red, black and white colour. Cortisol and THI were significantly lower ( P < 0.05) in summer season. Red blood cells, haematoglobin, haematocrit, mean cell volumes, white blood cells, neutrophils, lymphocytes, eosinophils and basophils were significantly different ( P < 0.05) as some associated with age across all seasons and correlated to THI. It was concluded that the location, coat colour and season had effects on hair length, cortisol levels, THI, HP and tick loads on different body parts and heat stress in Nguni cows.

  15. Effect of farm and simulated laboratory cold environmental conditions on the performance and physiological responses of lactating dairy cows supplemented with bovine somatotropin (BST)

    NASA Astrophysics Data System (ADS)

    Becker, B. A.; Johnson, H. D.; Li, R.; Collier, R. J.

    1990-09-01

    A study was conducted to evaluate the effect of bovine somatotropin (BST) supplementation in twelve lactating dairy cows maintained in cold environmental conditions. Six cows were injected daily with 25 mg of BST; the other six were injected with a control vehicle. Cows were maintained under standard dairy management during mid-winter for 30 days. Milk production was recorded twice daily, and blood samples were taken weekly. Animals were then transferred to environmentally controlled chambers and exposed to cycling thermoneutral (15° to 20° C) and cycling cold (-5° to +5° C) temperatures for 10 days in a split-reversal design. Milk production, feed and water intake, body weights and rectal temperatures were monitored. Blood samples were taken on days 1, 3, 5, 8 and 10 of each period and analyzed for plasma triiodothyronine (T3), thyroxine (T4), cortisol, insulin and prolactin. Under farm conditions, BST-treated cows produced 11% more milk than control-treated cows and in environmentally controlled chambers produced 17.4% more milk. No differences due to BST in feed or water intake, body weights or rectal temperatures were found under laboratory conditions. Plasma T3 and insulin increased due to BST treatment while no effect was found on cortisol, prolactin or T4. The results showed that the benefits of BST supplementation in lactating dairy cows were achieved under cold environmental conditions.

  16. Psycho-physiological mechanisms of adaptation of rotation personnel in Arctic regions.

    PubMed

    Krivoschekov, S G; Shishkina, T N

    1998-01-01

    Transit workers (240 oil industry workers, aged 19-50) living in the European part of Russia and flying to work in the northern regions of West Siberia (Tyumen district) were observed. Psychological status was determined by the method of Taylor. Biological rhythms, chemical control of ventilation, oxygen (O2) and carbon dioxide (CO2) consumption, body temperature, and hormone-metabolic data were assessed. The analysis of illness for the Nadymgazprom Enterprise was carried out in accordance with the medical charts. One may notice a certain cyclic recurrence of the adaptation process. Thus, the first stage of vigorous rearrangement of the psycho-physiological regulation system is followed by a period of relative stability, the result of initiation of compensatory processes. Compensation mechanisms, however, may become disabled, triggering development of a disadaptive state. Results of these scientific investigations were used to introduce new transit work regimens at Nadymgazprom Enterprise. PMID:10093319

  17. Intraspecific divergence of ionoregulatory physiology in the euryhaline teleost Fundulus heteroclitus: possible mechanisms of freshwater adaptation.

    PubMed

    Scott, Graham R; Rogers, Joseph T; Richards, Jeff G; Wood, Chris M; Schulte, Patricia M

    2004-09-01

    We examined intraspecific variation in ionoregulatory physiology within euryhaline killifish, Fundulus heteroclitus, to understand possible mechanisms of freshwater adaptation in fish. Pronounced differences in freshwater tolerance existed between northern (2% mortality) and southern (19% mortality) killifish populations after transfer from brackish water (10 g l(-1)) to freshwater. Differences in Na(+) regulation between each population might partially account for this difference in tolerance, because plasma Na(+) was decreased for a longer period in southern survivors than in northerns. Furthermore, northern fish increased Na(+)/K(+)-ATPase mRNA expression and activity in their gills to a greater extent 1-14 days after transfer than did southerns, which preceded higher whole-body net flux and unidirectional influx of Na(+) at 14 days. All observed differences in Na(+) regulation were small, however, and probably cannot account for the large differences in mortality. Differences in Cl(-) regulation also existed between populations. Plasma Cl(-) was maintained in northern fish, but in southerns, plasma Cl(-) decreased rapidly and remained low for the duration of the experiment. Correspondingly, net Cl(-) loss from southern fish remained high after transfer, while northerns eliminated Cl(-) loss altogether. Elevated Cl(-) loss from southern fish in freshwater was possibly due to a persistence of seawater gill morphology, as paracellular permeability (indicated by extrarenal clearance rate of PEG-4000) and apical crypt density in the gills (detected using scanning electron microscopy) were both higher than in northern fish. These large differences in the regulation of Cl(-) balance probably contributed to the marked differences in mortality after freshwater transfer. Glomerular filtration rate and urination frequency were also lower in southerns. Taken together, these data suggest that northern killifish are better adapted to freshwater environments and that minimizing Cl(-) imbalance appears to be the key physiological difference accounting for their greater freshwater tolerance. PMID:15326216

  18. Eco-physiological adaptation of dominant tree species at two contrasting karst habitats in southwestern China

    PubMed Central

    Wu, Qian; Yan, Hui; Xu, Xinwu

    2013-01-01

    The purpose of this study was to investigate the eco-physiological adaptation of indigenous woody species to their habitats in karst areas of southwestern China. Two contrasting forest habitats were studied: a degraded habitat in Daxiagu and a well-developed habitat in Tianlongshan, and the eco-physiological characteristics of the trees were measured for three growth seasons. Photosynthetic rate (Pn), stomatal conductance (gs), and transpiration rate (Tr) of the tree species in Daxiagu were 2-3 times higher than those in Tianlongshan under ambient conditions. However, this habitat effect was not significant when measurements were taken under controlled conditions. Under controlled conditions, Pn, gs, and Tr of the deciduous species were markedly higher than those for the evergreen species. Habitat had no significant effect on water use efficiency (WUE) or photochemical characteristics of PSII. The stomatal sensitivity of woody species in the degraded habitat was much higher than that in the well-developed habitat. Similarly, the leaf total nitrogen (N) and phosphorus (P) contents expressed on the basis of either dry mass or leaf area were also much higher in Daxiagu than they were in Tianlongshan. The mass-based leaf total N content of deciduous species was much higher than that of evergreen species, while leaf area-based total N and P contents of evergreens were significantly higher than those of deciduous species. The photosynthetic nitrogen- and phosphorus-use efficiencies (PNUE and PPUE) of deciduous species were much higher than those of evergreens. Further, the PPUE of the woody species in Tianlongshan was much higher than that  of the woody species in Daxiagu. The results from three growth seasons imply that the tree species were able to adapt well to their growth habitats. Furthermore, it seems that so-called “temporary drought stress” may not occur, or may not be severe for most woody plants in karst areas of southwestern China. PMID:24555059

  19. Physiological adaptation of an Antarctic Na+/K+-ATPase to the cold

    PubMed Central

    Galarza-Muñoz, Gaddiel; Soto-Morales, Sonia I.; Holmgren, Miguel; Rosenthal, Joshua J. C.

    2011-01-01

    SUMMARY Because enzymatic activity is strongly suppressed by the cold, polar poikilotherms face significant adaptive challenges. For example, at 0°C the catalytic activity of a typical enzyme from a temperate organism is reduced by more than 90%. Enzymes embedded in the plasma membrane, such as the Na+/K+-ATPase, may be even more susceptible to the cold because of thermal effects on the lipid bilayer. Accordingly, adaptive changes in response to the cold may include adjustments to the enzyme or the surrounding lipid environment, or synergistic changes to both. To assess the contribution of the enzyme itself, we cloned orthologous Na+/K+-ATPase ?-subunits from an Antarctic (Pareledone sp.; –1.8°C) and a temperate octopus (Octopus bimaculatus; ?18°C), and compared their turnover rates and temperature sensitivities in a heterologous expression system. The primary sequences of the two pumps were found to be highly similar (97% identity), with most differences being conservative changes involving hydrophobic residues. The physiology of the pumps was studied using an electrophysiological approach in intact Xenopus oocytes. The voltage dependence of the pumps was equivalent. However, at room temperature the maximum turnover rate of the Antarctic pump was found to be 25% higher than that of the temperate pump. In addition, the Antarctic pump exhibited a lower temperature sensitivity, leading to significantly higher relative activity at lower temperatures. Orthologous Na+/K+ pumps were then isolated from two tropical and two Arctic octopus. The temperature sensitivities of these pumps closely matched those of the temperate and Antarctic pumps, respectively. Thus, reduced thermal sensitivity appears to be a common mechanism driving cold adaptation in the Na+/K+-ATPase. PMID:21653810

  20. Haematological and immunological adaptations of non-pregnant, non-lactating dairy cows to a high-energetic diet containing mycotoxins.

    PubMed

    Dänicke, Sven; Meyer, Ulrich; Winkler, Janine; Ulrich, Sebastian; Frahm, Jana; Kersten, Susanne; Valenta, Hana; Rehage, Jürgen; Häussler, Susanne; Sauerwein, Helga; Locher, Lena

    2016-02-01

    Diet change and fatness are supposed to challenge the immune system of the cow. Therefore, immunological and haematological consequences of adaptation to and continued feeding of a high-energy diet were studied in eight non-pregnant, non-lactating Holstein cows over 16 weeks. Blood haptoglobin concentration remained unaltered, suggesting that an acute phase reaction was not induced. Stimulation ability of peripheral blood mononuclear cells and stimulated oxidative burst capacity of granulocytes increased significantly in the course of the experiment after an initial drop. While total leucocyte counts increased, the proportion of granulocytes increased and that of lymphocytes decreased at the same time as the ratio of CD4(+)/CD8(+) lymphocytes did. Capability of rumen microbes to detoxify the immune-modulating mycotoxin deoxynivalenol (DON) was not compromised as indicated by the exclusive presence of de-DON as the detoxified DON metabolite in blood. In conclusion, both diet change and prolonged positive energy balance influenced the bovine immune system. PMID:26654380

  1. Facilitated physiological adaptation to prolonged circadian disruption through dietary supplementation with essence of chicken.

    PubMed

    Wu, Tao; Yao, Cencen; Tsang, Fai; Huang, Liangfeng; Zhang, Wanjing; Jiang, Jianguo; Mao, Youxiang; Shao, Yujian; Kong, Boda; Singh, Paramjeet; Fu, Zhengwei

    2015-12-01

    Synchrony between circadian and metabolic processes is critical to the maintenance of energy homeostasis. Studies on essence of chicken (EC), a chicken meat extract rich in proteins, amino acids and peptides, showed its effectiveness in alleviating fatigue and promoting metabolism. A recent study revealed that it facilitated the re-entrainment of clock genes (Bmal1, Cry1, Dec1, Per1 and Per2) in the pineal gland and liver in a rat model of circadian disruption. Here, we investigated the role of EC-facilitated circadian synchrony in the maintenance of the energy homeostasis using a mouse model of prolonged circadian disruption. Prolonged circadian disruption (12 weeks) resulted in hepatic maladaptation, manifested by a mild but significant (p?physiological adaptation to the prolonged circadian disruption through facilitation of endogenous circadian synchrony and the coupling of circadian oscillators and metabolic regulators. This forms an important basis for further elucidation of the physiological benefits of EC-facilitated circadian synchrony. PMID:26595385

  2. Physiological adaptations involved in alkane assimilation at a low temperature by Rhodococcus sp. strain Q15.

    PubMed

    Whyte, L G; Slagman, S J; Pietrantonio, F; Bourbonnière, L; Koval, S F; Lawrence, J R; Inniss, W E; Greer, C W

    1999-07-01

    We examined physiological adaptations which allow the psychrotroph Rhodococcus sp. strain Q15 to assimilate alkanes at a low temperature (alkanes are contaminants which are generally insoluble and/or solid at low temperatures). During growth at 5 degrees C on hexadecane or diesel fuel, strain Q15 produced a cell surface-associated biosurfactant(s) and, compared to glucose-acetate-grown cells, exhibited increased cell surface hydrophobicity. A transmission electron microscopy examination of strain Q15 grown at 5 degrees C revealed the presence of intracellular electron-transparent inclusions and flocs of cells connected by an extracellular polymeric substance (EPS) when cells were grown on a hydrocarbon and morphological differences between the EPS of glucose-acetate-grown and diesel fuel-grown cells. A lectin binding analysis performed by using confocal scanning laser microscopy (CSLM) showed that the EPS contained a complex mixture of glycoconjugates, depending on both the growth temperature and the carbon source. Two glycoconjugates [beta-D-Gal-(1-3)-D-GlcNAc and alpha-L-fucose] were detected only on the surfaces of cells grown on diesel fuel at 5 degrees C. Using scanning electron microscopy, we observed strain Q15 cells on the surfaces of octacosane crystals, and using CSLM, we observed strain Q15 cells covering the surfaces of diesel fuel microdroplets; these findings indicate that this organism assimilates both solid and liquid alkane substrates at a low temperature by adhering to the alkane phase. Membrane fatty acid analysis demonstrated that strain Q15 adapted to growth at a low temperature by decreasing the degree of saturation of membrane lipid fatty acids, but it did so to a lesser extent when it was grown on hydrocarbons at 5 degrees C; these findings suggest that strain Q15 modulates membrane fluidity in response to the counteracting influences of low temperature and hydrocarbon toxicity. PMID:10388690

  3. Can supplementation with vitamin C and E alter physiological adaptations to strength training?

    PubMed Central

    2014-01-01

    Background Antioxidant supplementation has recently been demonstrated to be a double-edged sword, because small to moderate doses of exogenous antioxidants are essential or beneficial, while high doses may have adverse effects. The adverse effects can be manifested in attenuated effects of exercise and training, as the antioxidants may shut down some redox-sensitive signaling in the exercised muscle fibers. However, conditions such as age may potentially modulate the need for antioxidant intake. Therefore, this paper describes experiments for testing the hypothesis that high dosages of vitamin C (1000 mg/day) and E (235 mg/day) have negative effects on adaptation to resistance exercise and training in young volunteers, but positive effects in older men. Methods/design We recruited a total of 73 volunteers. The participants were randomly assigned to receiving either vitamin C and E supplementation or a placebo. The study design was double-blinded, and the participants followed an intensive training program for 10–12 weeks. Tests and measurements aimed at assessing changes in physical performance (maximal strength) and physiological characteristics (muscle mass), as well as biochemical and cellular systems and structures (e.g., cell signaling and morphology). Discussion Dietary supplements, such as vitamin C and E, are used by many people, especially athletes. The users often believe that high dosages of supplements improve health (resistance to illness and disease) and physical performance. These assumptions are, however, generally not supported in the scientific literature. On the contrary, some studies have indicated that high dosages of antioxidant supplements have negative effects on exercise-induced adaptation processes. Since this issue concerns many people and few randomized controlled trials have been conducted in humans, further studies are highly warranted. Trial registration ACTRN12614000065695 PMID:25075311

  4. Physiological and Proteomic Adaptation of the Alpine Grass Stipa purpurea to a Drought Gradient

    PubMed Central

    Yang, Yunqiang; Dong, Chao; Yang, Shihai; Li, Xiong; Sun, Xudong; Yang, Yongping

    2015-01-01

    Stipa purpurea, an endemic forage species on the Tibetan Plateau, is highly resistant to cold and drought, but the mechanisms underlying its responses to drought stress remain elusive. An understanding of such mechanisms may be useful for developing cultivars that are adaptable to water deficit. In this study, we analyzed the physiological and proteomic responses of S. purpurea under increasing drought stress. Seedlings of S. purpurea were subjected to a drought gradient in a controlled experiment, and proteins showing changes in abundance under these conditions were identified by two-dimensional electrophoresis followed by mass spectrometry analysis. A western blotting analysis was conducted to confirm the increased abundance of a heat-shock protein, NCED2, and a dehydrin in S. purpurea seedlings under drought conditions. We detected carbonylated proteins to identify oxidation-sensitive proteins in S. purpurea seedlings, and found that ribulose-1, 5-bisphosphate carboxylase oxygenase (RuBisCO) was one of the oxidation-sensitive proteins under drought. Together, these results indicated drought stress might inhibit photosynthesis in S. purpurea by oxidizing RuBisCO, but the plants were able to maintain photosynthetic efficiency by a compensatory upregulation of unoxidized RuBisCO and other photosynthesis-related proteins. Further analyses confirmed that increased abundance of antioxidant enzymes could balance the redox status of the plants to mitigate drought-induced oxidative damage. PMID:25646623

  5. NaCl-induced physiological and biochemical adaptative mechanisms in the ornamental Myrtus communis L. plants.

    PubMed

    Acosta-Motos, José Ramón; Diaz-Vivancos, Pedro; Álvarez, Sara; Fernández-García, Nieves; Sánchez-Blanco, María Jesús; Hernández, José Antonio

    2015-07-01

    Physiological and biochemical changes in Myrtus communis L. plants after being subjected to different solutions of NaCl (44, and 88 mM) for up to 30 days (Phase I) and after recovery from the salinity period (Phase II) were studied. Myrtle plants showed salinity tolerance by displaying a series of adaptative mechanisms to cope with salt-stress, including controlled ion homeostasis, the increase in root/shoot ratio, the reduction of water potentials and stomatal conductance to limit water loss. In addition, they displayed different strategies to protect the photosynthetic machinery, including limiting toxic ion accumulation in leaves, increase in chlorophyll content, and changes in chlorophyll fluorescence parameters, leaf anatomy and increases in catalase activity. Anatomical modifications in leaves, including a decrease in spongy parenchyma and increased intercellular spaces, allow CO2 diffusion in a situation of reduced stomatal aperture. In spite of all these changes, salinity produced oxidative stress in myrtle plants as monitored by increases in oxidative stress parameter values. The post-recovery period is perceived as a new stress situation, as observed through effects on plant growth and alterations in non-photochemical quenching parameters and lipid peroxidation values. PMID:26074356

  6. Physiological and proteomic adaptation of the alpine grass Stipa purpurea to a drought gradient.

    PubMed

    Yang, Yunqiang; Dong, Chao; Yang, Shihai; Li, Xiong; Sun, Xudong; Yang, Yongping

    2015-01-01

    Stipa purpurea, an endemic forage species on the Tibetan Plateau, is highly resistant to cold and drought, but the mechanisms underlying its responses to drought stress remain elusive. An understanding of such mechanisms may be useful for developing cultivars that are adaptable to water deficit. In this study, we analyzed the physiological and proteomic responses of S. purpurea under increasing drought stress. Seedlings of S. purpurea were subjected to a drought gradient in a controlled experiment, and proteins showing changes in abundance under these conditions were identified by two-dimensional electrophoresis followed by mass spectrometry analysis. A western blotting analysis was conducted to confirm the increased abundance of a heat-shock protein, NCED2, and a dehydrin in S. purpurea seedlings under drought conditions. We detected carbonylated proteins to identify oxidation-sensitive proteins in S. purpurea seedlings, and found that ribulose-1, 5-bisphosphate carboxylase oxygenase (RuBisCO) was one of the oxidation-sensitive proteins under drought. Together, these results indicated drought stress might inhibit photosynthesis in S. purpurea by oxidizing RuBisCO, but the plants were able to maintain photosynthetic efficiency by a compensatory upregulation of unoxidized RuBisCO and other photosynthesis-related proteins. Further analyses confirmed that increased abundance of antioxidant enzymes could balance the redox status of the plants to mitigate drought-induced oxidative damage. PMID:25646623

  7. Adaptation and evaluation of the GrazeIn model of grass dry matter intake and milk yield prediction for grazing dairy cows.

    PubMed

    O'Neill, B F; Ruelle, E; O'Donovan, M; Shalloo, L; Mulligan, F J; Boland, T M; Delaby, L; Delagarde, R; Lewis, E

    2014-04-01

    The prediction of grass dry matter intake (GDMI) and milk yield (MY) are important to aid sward and grazing management decision making. Previous evaluations of the GrazeIn model identified weaknesses in the prediction of GDMI and MY for grazing dairy cows. To increase the accuracy of GDMI and MY prediction, GrazeIn was adapted, and then re-evaluated, using a data set of 3960 individual cow measurements. The adaptation process was completed in four additive steps with different components of the model reparameterised or altered. These components were: (1) intake capacity (IC) that was increased by 5% to reduce a general GDMI underprediction. This resulted in a correction of the GDMI mean and a lower relative prediction error (RPE) for the total data set, and at all stages of lactation, compared with the original model; (2) body fat reserve (BFR) deposition from 84 days in milk to next calving that was included in the model. This partitioned some energy to BFR deposition after body condition score nadir had been reached. This reduced total energy available for milk production, reducing the overprediction of MY and reducing RPE for MY in mid and late lactation, compared with the previous step. There was no effect on predicted GDMI; (3) The potential milk curve was reparameterised by optimising the rate of decrease in the theoretical hormone related to secretory cell differentiation and the basal rate of secretory cell death to achieve the lowest possible mean prediction error (MPE) for MY. This resulted in a reduction in the RPE for MY and an increase in the RPE for GDMI in all stages of lactation compared with the previous step; and (4) finally, IC was optimised, for GDMI, to achieve the lowest possible MPE. This resulted in an IC correction coefficient of 1.11. This increased the RPE for MY but decreased the RPE for GDMI compared with the previous step. Compared with the original model, modifying this combination of four model components improved the prediction accuracy of MY, particularly in late lactation with a decrease in RPE from 27.8% in the original model to 22.1% in the adapted model. However, testing of the adapted model using an independent data set would be beneficial and necessary to make definitive conclusions on improved predictions. PMID:24438821

  8. A Chemosensory Adaptation Module for the Physiology Laboratory from Student-Directed "C. elegans" Research

    ERIC Educational Resources Information Center

    Lindblom, Tim

    2006-01-01

    The model organism, "Caenorhabditis elegans," in addition to being well suited to genetics and cell biology teaching applications, can also be useful in the physiology laboratory. In this article, the author describes how students in a junior level college Comparative Physiology course have made use of "C. elegans" in semester-long,…

  9. Annual Research Review: The Neurobiology and Physiology of Resilience and Adaptation across the Life Course

    ERIC Educational Resources Information Center

    Karatoreos, Ilia N.; McEwen, Bruce S.

    2013-01-01

    Background: Adaptation is key to survival. An organism must adapt to environmental challenges in order to be able to thrive in the environment in which they find themselves. Resilience can be thought of as a measure of the ability of an organism to adapt, and to withstand challenges to its stability. In higher animals, the brain is a key player in…

  10. SIRT1 is a Highly Networked Protein That Mediates the Adaptation to Chronic Physiological Stress

    PubMed Central

    Clark-Knowles, Katherine V.; Caron, Annabelle Z.; Gray, Douglas A.

    2013-01-01

    SIRT1 is a NAD+-dependent protein deacetylase that has a very large number of established protein substrates and an equally impressive list of biological functions thought to be regulated by its activity. Perhaps as notable is the remarkable number of points of conflict concerning the role of SIRT1 in biological processes. For example, evidence exists suggesting that SIRT1 is a tumor suppressor, is an oncogene, or has no effect on oncogenesis. Similarly, SIRT1 is variably reported to induce, inhibit, or have no effect on autophagy. We believe that the resolution of many conflicting results is possible by considering recent reports indicating that SIRT1 is an important hub interacting with a complex network of proteins that collectively regulate a wide variety of biological processes including cancer and autophagy. A number of the interacting proteins are themselves hubs that, like SIRT1, utilize intrinsically disordered regions for their promiscuous interactions. Many studies investigating SIRT1 function have been carried out on cell lines carrying undetermined numbers of alterations to the proteins comprising the SIRT1 network or on inbred mouse strains carrying fixed mutations affecting some of these proteins. Thus, the effects of modulating SIRT1 amount and/or activity are importantly determined by the genetic background of the cell (or the inbred strain of mice), and the effects attributed to SIRT1 are synthetic with the background of mutations and epigenetic differences between cells and organisms. Work on mice carrying alterations to the Sirt1 gene suggests that the network in which SIRT1 functions plays an important role in mediating physiological adaptation to various sources of chronic stress such as calorie restriction and calorie overload. Whether the catalytic activity of SIRT1 and the nuclear concentration of the co-factor, NAD+, are responsible for modulating this activity remains to be determined. However, the effect of modulating SIRT1 activity must be interpreted in the context of the cell or tissue under investigation. Indeed, for SIRT1, we argue that context is everything. PMID:24020004

  11. HEMOGLOBIN FUNCTION AND PHYSIOLOGICAL ADAPTATION TO HYPOXIA IN HIGH-ALTITUDE MAMMALS

    E-print Network

    Storz, Jay F.

    -altitude environments present a number of physiolog- ical challenges for endothermic animals, as they are character impose severe constraints on aerobic metabolism and may therefore influence an animal's food requirements

  12. Effects of Prepartum Dietary Energy Level and Nicotinic Acid Supplementation on Immunological, Hematological and Biochemical Parameters of Periparturient Dairy Cows Differing in Parity

    PubMed Central

    Tienken, Reka; Kersten, Susanne; Frahm, Jana; Hüther, Liane; Meyer, Ulrich; Huber, Korinna; Rehage, Jürgen; Dänicke, Sven

    2015-01-01

    Simple Summary Several biological changes occur during the transition from late pregnancy to early lactation which is associated with a high susceptibility of health disorders. Nicotinic acid, as feed additive, is suggested to balance catabolic metabolism of periparturient dairy cows by attenuating lipolysis and impact production performance. This study provides information of the biological changes occurring around parturition with special emphasis on differences between primiparous and multiparous cows. Present results showed that energy-dense feeding prepartum did not result in metabolic imbalances postpartum in dairy cows which were similar in body condition score. Nicotinic acid supplementation did not reveal any effect. Abstract The periparturient period is critical according to health, productivity and profitability. As this period is fundamental for the success of the lactation period, the interest in improving periparturient health by dietary supplements increased in recent years. The present study investigated the effects of feeding nicotinic acid (NA) combined with varying dietary energy densities on immunological, hematological and biochemical parameters of periparturient cows differing in parity. Thirty-six multiparous and 20 primiparous dairy cows were enrolled in the study 42 days before expected parturition date until 100 days postpartum with the half of the cows being supplemented with 24 g of NA/d. After parturition a diet with 30% concentrate was fed to all cows which was followed by different concentrate escalation strategies. Dietary NA supplementation was ceased on day 24 postpartum. Dietary NA increased (P = 0.010) serum nicotinamide concentrations (mean of 3.35 ± 1.65 µg/mL), whereas NA could not be detected. Present data emphasize that periparturient cows are faced with major physiological challenges and that both parity-groups have different prerequisites to adapt to those changes irrespective of NA supplementation. The overfeeding of energy to cows which were similar in body condition score had only minor effects on periparturient immune system function and the metabolism of those cows. PMID:26479393

  13. Effects of Prepartum Dietary Energy Level and Nicotinic Acid Supplementation on Immunological, Hematological and Biochemical Parameters of Periparturient Dairy Cows Differing in Parity.

    PubMed

    Tienken, Reka; Kersten, Susanne; Frahm, Jana; Hüther, Liane; Meyer, Ulrich; Huber, Korinna; Rehage, Jürgen; Dänicke, Sven

    2015-01-01

    The periparturient period is critical according to health, productivity and profitability. As this period is fundamental for the success of the lactation period, the interest in improving periparturient health by dietary supplements increased in recent years. The present study investigated the effects of feeding nicotinic acid (NA) combined with varying dietary energy densities on immunological, hematological and biochemical parameters of periparturient cows differing in parity. Thirty-six multiparous and 20 primiparous dairy cows were enrolled in the study 42 days before expected parturition date until 100 days postpartum with the half of the cows being supplemented with 24 g of NA/d. After parturition a diet with 30% concentrate was fed to all cows which was followed by different concentrate escalation strategies. Dietary NA supplementation was ceased on day 24 postpartum. Dietary NA increased (P = 0.010) serum nicotinamide concentrations (mean of 3.35 ± 1.65 µg/mL), whereas NA could not be detected. Present data emphasize that periparturient cows are faced with major physiological challenges and that both parity-groups have different prerequisites to adapt to those changes irrespective of NA supplementation. The overfeeding of energy to cows which were similar in body condition score had only minor effects on periparturient immune system function and the metabolism of those cows. PMID:26479393

  14. Adaptability of buffaloes to climatic stress, as assessed by physiological reactions.

    PubMed

    Garg, S K; Nangia, O P

    1990-01-01

    Among the physiological reactions to climate, the haematocrit value had a tendency to increase in the hotter months, though the increase observed was within physiological limits. Rectal temperature did not change to significantly higher levels, during the months with average ambient temperatures in the region of 25.1-31.6 degrees C. Similarly, pulse rates, too, increased in parallel to rising ambient temperatures. PMID:2241491

  15. Possible involvement of oxytocin in modulating the stress response in lactating dairy cows

    PubMed Central

    Sutherland, Mhairi A.; Tops, Mattie

    2014-01-01

    Oxytocin can attenuate the physiological and behavioral response to stress in animals. In this study we investigated the relationship between plasma oxytocin concentrations and the behavioral and physiological response of dairy cows to a repeated psychological stressor (novel environment). Twenty lactating multi-parous dairy cows were milked in a familiar milking parlor and in a novel environment. Blood samples were collected before and after milking in the familiar parlor (baseline) and on the second and fifth day in the novel parlor to measure plasma cortisol and oxytocin concentrations. Heart rate was recorded on all cows during milking in the familiar and novel environment. On all test days, the behavioral response of cows to milk cluster attachment was scored. On day 2 in the novel parlor, the oxytocin response, cortisol concentrations and heart rate were greater, and heart rate variability was lower than baseline values recorded in the familiar parlor. The results from this study suggest that oxytocin release is increased in response to exposure to a psychological stressor (novel environment) and that cows adapt to this stressor over time. After initial suppression, oxytocin levels increased over days of milking in a novel environment, whereas indicators of stress simultaneously decreased. Furthermore, the oxytocin increase was associated with habituation of the cortisol response in anticipation of milking in a novel environment, suggesting that oxytocin may be involved in habituation to a novel environment in dairy cows. This mechanism of habituation to novel environments may reflect an association between oxytocin and a “familiarization-habituation response” to repeated exposure to an initially novel environment that has previously been reported in humans. PMID:25228892

  16. An Approximation to the Adaptive Exponential Integrate-and-Fire Neuron Model Allows Fast and Predictive Fitting to Physiological Data

    PubMed Central

    Hertäg, Loreen; Hass, Joachim; Golovko, Tatiana; Durstewitz, Daniel

    2012-01-01

    For large-scale network simulations, it is often desirable to have computationally tractable, yet in a defined sense still physiologically valid neuron models. In particular, these models should be able to reproduce physiological measurements, ideally in a predictive sense, and under different input regimes in which neurons may operate in vivo. Here we present an approach to parameter estimation for a simple spiking neuron model mainly based on standard f–I curves obtained from in vitro recordings. Such recordings are routinely obtained in standard protocols and assess a neuron’s response under a wide range of mean-input currents. Our fitting procedure makes use of closed-form expressions for the firing rate derived from an approximation to the adaptive exponential integrate-and-fire (AdEx) model. The resulting fitting process is simple and about two orders of magnitude faster compared to methods based on numerical integration of the differential equations. We probe this method on different cell types recorded from rodent prefrontal cortex. After fitting to the f–I current-clamp data, the model cells are tested on completely different sets of recordings obtained by fluctuating (“in vivo-like”) input currents. For a wide range of different input regimes, cell types, and cortical layers, the model could predict spike times on these test traces quite accurately within the bounds of physiological reliability, although no information from these distinct test sets was used for model fitting. Further analyses delineated some of the empirical factors constraining model fitting and the model’s generalization performance. An even simpler adaptive LIF neuron was also examined in this context. Hence, we have developed a “high-throughput” model fitting procedure which is simple and fast, with good prediction performance, and which relies only on firing rate information and standard physiological data widely and easily available. PMID:22973220

  17. Rectal temperatures, respiratory rates, production, and reproduction performances of crossbred Girolando cows under heat stress in northeastern Brazil.

    PubMed

    da Costa, Antônio Nélson Lima; Feitosa, José Valmir; Montezuma, Péricles Afonso; de Souza, Priscila Teixeira; de Araújo, Airton Alencar

    2015-11-01

    This study compared the two breed groups of Girolando (½ Holstein ½ Gyr vs. ¾ Holstein ¼ Gyr) through analysis of the percentages (stressed or non-stressed cows) of rectal temperature (RT), respiratory rate (RR) and pregnancy rate (PR), and means of production and reproduction parameters to determine the group best suited to rearing in semiarid tropical climate. The experiment was conducted at the farm, in the municipality of Umirim, State of Ceará, Brazil. Two hundred and forty cows were used in a 2?×?2 factorial study; 120 of each group were kept under an intensive system during wet and dry seasons. The environmental parameters obtained were relative humidity (RH), air temperature (AT), and the temperature and humidity index (THI). Pregnancy diagnosis (PD) was determined by ultrasonography 30 days after artificial insemination (AI). The milk production of each cow was recorded with automated milkings in the farm. The variables were expressed as mean and standard error, evaluated by ANOVA at 5 % probability using the GLM procedure of SAS. Chi-square test at 5 % probability was applied to data of RT, RR, pregnancy rate (PR), and the number of AIs to obtain pregnancy. The majority of ½ Holstein cows showed mean values of RT and RR within the normal range in both periods and shifts. Most animals of the ¾ Holstein group exhibited the RR means above normal during the afternoon in the rainy and dry periods and RT means above normal during the afternoon in the dry period. After analyses, ½ Holstein crossbred cows are more capable of thermoregulating than ¾ Holstein cows under conditions of thermal stress, and the dry period was more impacting for bovine physiology with significant changes in physiological parameters, even for the first breed group. Knowledge of breed groups adapted to climatic conditions of northeastern Brazil can directly assist cattle farmers in selecting animals best adapted for forming herds. PMID:25702060

  18. Rectal temperatures, respiratory rates, production, and reproduction performances of crossbred Girolando cows under heat stress in northeastern Brazil

    NASA Astrophysics Data System (ADS)

    da Costa, Antônio Nélson Lima; Feitosa, José Valmir; Montezuma, Péricles Afonso; de Souza, Priscila Teixeira; de Araújo, Airton Alencar

    2015-02-01

    This study compared the two breed groups of Girolando (½ Holstein ½ Gyr vs. ¾ Holstein ¼ Gyr) through analysis of the percentages (stressed or non-stressed cows) of rectal temperature (RT), respiratory rate (RR) and pregnancy rate (PR), and means of production and reproduction parameters to determine the group best suited to rearing in semiarid tropical climate. The experiment was conducted at the farm, in the municipality of Umirim, State of Ceará, Brazil. Two hundred and forty cows were used in a 2 × 2 factorial study; 120 of each group were kept under an intensive system during wet and dry seasons. The environmental parameters obtained were relative humidity (RH), air temperature (AT), and the temperature and humidity index (THI). Pregnancy diagnosis (PD) was determined by ultrasonography 30 days after artificial insemination (AI). The milk production of each cow was recorded with automated milkings in the farm. The variables were expressed as mean and standard error, evaluated by ANOVA at 5 % probability using the GLM procedure of SAS. Chi-square test at 5 % probability was applied to data of RT, RR, pregnancy rate (PR), and the number of AIs to obtain pregnancy. The majority of ½ Holstein cows showed mean values of RT and RR within the normal range in both periods and shifts. Most animals of the ¾ Holstein group exhibited the RR means above normal during the afternoon in the rainy and dry periods and RT means above normal during the afternoon in the dry period. After analyses, ½ Holstein crossbred cows are more capable of thermoregulating than ¾ Holstein cows under conditions of thermal stress, and the dry period was more impacting for bovine physiology with significant changes in physiological parameters, even for the first breed group. Knowledge of breed groups adapted to climatic conditions of northeastern Brazil can directly assist cattle farmers in selecting animals best adapted for forming herds.

  19. Rectal temperatures, respiratory rates, production, and reproduction performances of crossbred Girolando cows under heat stress in northeastern Brazil

    NASA Astrophysics Data System (ADS)

    da Costa, Antônio Nélson Lima; Feitosa, José Valmir; Montezuma, Péricles Afonso; de Souza, Priscila Teixeira; de Araújo, Airton Alencar

    2015-11-01

    This study compared the two breed groups of Girolando (½ Holstein ½ Gyr vs. ¾ Holstein ¼ Gyr) through analysis of the percentages (stressed or non-stressed cows) of rectal temperature (RT), respiratory rate (RR) and pregnancy rate (PR), and means of production and reproduction parameters to determine the group best suited to rearing in semiarid tropical climate. The experiment was conducted at the farm, in the municipality of Umirim, State of Ceará, Brazil. Two hundred and forty cows were used in a 2 × 2 factorial study; 120 of each group were kept under an intensive system during wet and dry seasons. The environmental parameters obtained were relative humidity (RH), air temperature (AT), and the temperature and humidity index (THI). Pregnancy diagnosis (PD) was determined by ultrasonography 30 days after artificial insemination (AI). The milk production of each cow was recorded with automated milkings in the farm. The variables were expressed as mean and standard error, evaluated by ANOVA at 5 % probability using the GLM procedure of SAS. Chi-square test at 5 % probability was applied to data of RT, RR, pregnancy rate (PR), and the number of AIs to obtain pregnancy. The majority of ½ Holstein cows showed mean values of RT and RR within the normal range in both periods and shifts. Most animals of the ¾ Holstein group exhibited the RR means above normal during the afternoon in the rainy and dry periods and RT means above normal during the afternoon in the dry period. After analyses, ½ Holstein crossbred cows are more capable of thermoregulating than ¾ Holstein cows under conditions of thermal stress, and the dry period was more impacting for bovine physiology with significant changes in physiological parameters, even for the first breed group. Knowledge of breed groups adapted to climatic conditions of northeastern Brazil can directly assist cattle farmers in selecting animals best adapted for forming herds.

  20. Functional Validation of Hydrophobic Adaptation to Physiological Temperature in the Small Heat Shock Protein ?A-crystallin

    PubMed Central

    Posner, Mason; Kiss, Andor J.; Skiba, Jackie; Drossman, Amy; Dolinska, Monika B.; Hejtmancik, J. Fielding; Sergeev, Yuri V.

    2012-01-01

    Small heat shock proteins (sHsps) maintain cellular homeostasis by preventing stress and disease-induced protein aggregation. While it is known that hydrophobicity impacts the ability of sHsps to bind aggregation-prone denaturing proteins, the complex quaternary structure of globular sHsps has made understanding the significance of specific changes in hydrophobicity difficult. Here we used recombinant protein of the lenticular sHsp ? A-crystallin from six teleost fishes environmentally adapted to temperatures ranging from -2°C to 40°C to identify correlations between physiological temperature, protein stability and chaperone-like activity. Using sequence and structural modeling analysis we identified specific amino acid differences between the warm adapted zebrafish and cold adapted Antarctic toothfish that could contribute to these correlations and validated the functional consequences of three specific hydrophobicity-altering amino acid substitutions in ?A-crystallin. Site directed mutagenesis of three residues in the zebrafish (V62T, C143S, T147V) confirmed that each impacts either protein stability or chaperone-like activity or both, with the V62T substitution having the greatest impact. Our results indicate a role for changing hydrophobicity in the thermal adaptation of ? A-crystallin and suggest ways to produce sHsp variants with altered chaperone-like activity. These data also demonstrate that a comparative approach can provide new information about sHsp function and evolution. PMID:22479631

  1. Influence of a deficient intake of high and low degradable protein on body composition, metabolic adaptation, production and reproductive performance in early lactation dairy cows.

    PubMed

    Fekete, S; Huszenicza, G; Kellems, R O; Szakáll, I; Fébel, H; Husvéth, F; Nagy, P; Kulcsár, M; Kósa, E; Gaál, T; Rudas, P; Oppel, K

    1996-01-01

    High-yielding dairy cows (n = 34) were divided into high (HD) and low (LD) protein degradability groups after delivery, and used for a feeding trial which lasted up to day 80 +/- 10 of lactation. The cows were regularly weighed, their body condition was scored (BCS), and their reproductive status assessed. Blood samples were taken simultaneously, and ruminal fluid was collected on the last day of the trial. On postpartum day 45 +/- 6 and 11 days thereafter two prostaglandin F2 alpha (PGF2 alpha) injections were administered. The ammonia and urea concentrations of the ruminal fluid were higher in cows of group HD. The C2:C3 ratio was 2.7:1 vs. 2.3:1 in HD and LD cows, respectively. The amino acid and lipid composition of blood reflected the dietary treatments. The BCS and blood urea concentration were slightly higher in HD animals. The average daily milk production of LD cows was 1.5 kg higher than that of HD cows. The pregnancy rates of the two groups at day 200 after calving did not differ, but LD cows showed their first visible oestrus and reconceived significantly (p < 0.05) later. It can be concluded that--at a marginal energy supply-a moderate (13%) deficiency of rumen-degradable protein during the first 10 weeks after calving can be more detrimental to reproductive performance than a severe (27%) deficiency of undegradable protein. PMID:9055456

  2. Summary Physiological acclimation and genotypic adapta-tion to prevailing temperatures may influence forest responses

    E-print Network

    Pennycook, Steve

    conditions. Neverthe- less, physiologically based models should incorporate sea- sonal acclimation and regeneration of particu- lar species assemblages (Solomon 1986, Pastor and Post 1988, Martin 1992, Shugart et of the current geo- graphic range and zero growth at the northern and southern limits (Solomon 1986, Shugart et

  3. Space Physiology within an Exercise Physiology Curriculum

    ERIC Educational Resources Information Center

    Carter, Jason R.; West, John B.

    2013-01-01

    Compare and contrast strategies remain common pedagogical practices within physiological education. With the support of an American Physiological Society Teaching Career Enhancement Award, we have developed a junior- or senior-level undergraduate curriculum for exercise physiology that compares and contrasts the physiological adaptations of…

  4. Effect of adaptation strategies when feeding fresh cassava foliage on intake and physiological responses of lambs.

    PubMed

    Hue, Khuc Thi; Van, Do Thi Thanh; Spörndly, Eva; Ledin, Inger; Wredle, Ewa

    2012-02-01

    The objective of the experiment was to study different adaptation strategies to avoid HCN intoxication when feeding fresh cassava foliage to sheep. Twenty-four Phan Rang lambs (initial weight = 19.6 kg at 5.5 months of age) were used in the study. The four experimental diets contained guinea grass (Panicum maximum) supplemented with concentrate at 1.5% of body weight (BW) as dry matter (DM) (control) or supplemented with fresh cassava foliage (FCF) that was introduced into the diet with an adaptation period of 0 (FCF-0), 7 (FCF-7) or 21 (FCF-21) days before reaching the target feeding level of 2% of BW. The average intake of FCF expressed as DM was not different amongst the supplemented treatments and ranged from 1.4 to 1.5% of BW but gradually increased during the first 7 days without any adaptation. The hydrogen cyanide consumed varied from 5.1 to 5.4 mg/kg BW and no difference between treatments with cassava foliage in the diet was found. The live weight gain was significantly higher in the treatments control and FCF-7 compared to FCF-21. No significant differences in heart rate, respiration rate and rumen movement were found between diets. The thiocyanate concentration in the urine of the lambs increased concomitantly with the increase in fresh cassava foliage offered during the first part of the experiment. In conclusion, an adaptation period of approximately 7 days seems to be favourable in combined diets where cassava foliage is offered in quantities up to 2% of BW. This level of intake could enhance the intake and LWG of the lambs without any documented effects on heart rate, respiration rate or rumen movements. PMID:22081316

  5. Evaluating adaptation options of microcirculatory-tissue systems based on the physiological link of nutritive blood flow and redox ratio

    NASA Astrophysics Data System (ADS)

    Krupatkin, Alexander I.; Sidorov, Victor V.; Dremin, Victor V.; Dunaev, Andrey V.; Novikova, Irina N.; Zhu, Simian; Nabi, Ghulam; Litvinova, Karina S.; Baklanova, Anastasia P.; Bakshaliev, Ruslan M.; Ravcheev, Sergey A.

    2015-03-01

    Fluorescent spectroscopy (FS) is becoming more widely used in chemistry, biology, in various fields of medical technology and medicine in general. Many purulent wounds, burns and other destructive inflammatory processes are accompanied by changes in the fluorescent activity of the tissues, which occurs due to a misbalance in accumulation of natural fluorophores: FAD, NADH, lipofuscin, porphyrins, structural proteins, etc. The study of redox ratio (RR), characterizing the metabolic processes, is important in the assessment of the metabolic activity ofmicrocirculatory-tissue systems (MTS). However, one of the big problems of the FS method is still the correct interpretation of the data and the development of practical methods for its application in clinical medicine. To solve this problem and create new diagnostic criteria, we propose to evaluate the adaptive capacity of MTS using indicators of links between nutritive blood flow and redox ratio during a physiological rest and functional load (occlusion test). As is known, these parameters (RR and nutritive blood flow) characterize the metabolic activity of tissues.We have performedan experimental study of the relationship between the RR, defined by FS, and nutritive blood flow, defined by the methods of laser Doppler flowmetry. Preliminary results in the study of a complex approach to diagnosis of the state of biological tissue were obtained. A positive relationship between the nutritive blood flow in the microcirculatory channel and RR of skin tissue is observed.The speed of change of metabolism in the phase of occlusion and reperfusion and duration of phase of recovery may be the criteria for adaptive capabilities of MTS, which has practical significance for physiology and medicine.

  6. Modulation of extracellular matrix genes reflects the magnitude of physiological adaptation to aerobic exercise training in humans

    PubMed Central

    Timmons, James A; Jansson, Eva; Fischer, Helene; Gustafsson, Thomas; Greenhaff, Paul L; Ridden, John; Rachman, Jonathan; Sundberg, Carl Johan

    2005-01-01

    Background Regular exercise reduces cardiovascular and metabolic disease partly through improved aerobic fitness. The determinants of exercise-induced gains in aerobic fitness in humans are not known. We have demonstrated that over 500 genes are activated in response to endurance-exercise training, including modulation of muscle extracellular matrix (ECM) genes. Real-time quantitative PCR, which is essential for the characterization of lower abundance genes, was used to examine 15 ECM genes potentially relevant for endurance-exercise adaptation. Twenty-four sedentary male subjects undertook six weeks of high-intensity aerobic cycle training with muscle biopsies being obtained both before and 24 h after training. Subjects were ranked based on improvement in aerobic fitness, and two cohorts were formed (n = 8 per group): the high-responder group (HRG; peak rate of oxygen consumption increased by +0.71 ± 0.1 L min-1; p < 0.0001) while the low-responder group (LRG; peak rate of oxygen consumption did not change, +0.17 ± 0.1 L min-1, ns). ECM genes profiled included the angiopoietin 1 and related genes (angiopoietin 2, tyrosine kinase with immunoglobulin-like and EGF-like domains 1 (TIE1) and 2 (TIE2), vascular endothelial growth factor (VEGF) and related receptors (VEGF receptor 1, VEGF receptor 2 and neuropilin-1), thrombospondin-4, ?2-macroglobulin and transforming growth factor ?2. Results neuropilin-1 (800%; p < 0.001) and VEGF receptor 2 (300%; p < 0.01) transcript abundance increased only in the HRG, whereas levels of VEGF receptor 1 mRNA actually declined in the LRG (p < 0.05). TIE1 and TIE2 mRNA levels were unaltered in the LRG, whereas transcription levels of both genes were increased by 2.5-fold in the HRG (p < 0.01). Levels of thrombospondin-4 (900%; p < 0.001) and ?2-macroglobulin (300%, p < 0.05) mRNA increased substantially in the HRG. In contrast, the amount of transforming growth factor ?2 transcript increased only in the HRG (330%; p < 0.01), whereas it remained unchanged in the LRG (-80%). Conclusion We demonstrate for the first time that aerobic training activates angiopoietin 1 and TIE2 genes in human muscle, but only when aerobic capacity adapts to exercise-training. The fourfold-greater increase in aerobic fitness and markedly differing gene expression profile in the HRG indicates that these ECM genes may be critical for physiological adaptation to exercise in humans. In addition, we show that, without careful demonstration of physiological adaptation, conclusions derived from gene expression profiling of human skeletal muscle following exercise may be of limited value. We propose that future studies should (a) investigate the mechanisms that underlie the apparent link between physiological adaptation and gene expression and (b) use the genes profiled in this paper as candidates for population genetic studies. PMID:16138928

  7. Inhibition of MCU forces extramitochondrial adaptations governing physiological and pathological stress responses in heart.

    PubMed

    Rasmussen, Tyler P; Wu, Yuejin; Joiner, Mei-ling A; Koval, Olha M; Wilson, Nicholas R; Luczak, Elizabeth D; Wang, Qinchuan; Chen, Biyi; Gao, Zhan; Zhu, Zhiyong; Wagner, Brett A; Soto, Jamie; McCormick, Michael L; Kutschke, William; Weiss, Robert M; Yu, Liping; Boudreau, Ryan L; Abel, E Dale; Zhan, Fenghuang; Spitz, Douglas R; Buettner, Garry R; Song, Long-Sheng; Zingman, Leonid V; Anderson, Mark E

    2015-07-21

    Myocardial mitochondrial Ca(2+) entry enables physiological stress responses but in excess promotes injury and death. However, tissue-specific in vivo systems for testing the role of mitochondrial Ca(2+) are lacking. We developed a mouse model with myocardial delimited transgenic expression of a dominant negative (DN) form of the mitochondrial Ca(2+) uniporter (MCU). DN-MCU mice lack MCU-mediated mitochondrial Ca(2+) entry in myocardium, but, surprisingly, isolated perfused hearts exhibited higher O2 consumption rates (OCR) and impaired pacing induced mechanical performance compared with wild-type (WT) littermate controls. In contrast, OCR in DN-MCU-permeabilized myocardial fibers or isolated mitochondria in low Ca(2+) were not increased compared with WT, suggesting that DN-MCU expression increased OCR by enhanced energetic demands related to extramitochondrial Ca(2+) homeostasis. Consistent with this, we found that DN-MCU ventricular cardiomyocytes exhibited elevated cytoplasmic [Ca(2+)] that was partially reversed by ATP dialysis, suggesting that metabolic defects arising from loss of MCU function impaired physiological intracellular Ca(2+) homeostasis. Mitochondrial Ca(2+) overload is thought to dissipate the inner mitochondrial membrane potential (??m) and enhance formation of reactive oxygen species (ROS) as a consequence of ischemia-reperfusion injury. Our data show that DN-MCU hearts had preserved ??m and reduced ROS during ischemia reperfusion but were not protected from myocardial death compared with WT. Taken together, our findings show that chronic myocardial MCU inhibition leads to previously unanticipated compensatory changes that affect cytoplasmic Ca(2+) homeostasis, reprogram transcription, increase OCR, reduce performance, and prevent anticipated therapeutic responses to ischemia-reperfusion injury. PMID:26153425

  8. Induction of osmoadaptive mechanisms and modulation of cellular physiology help Bacillus licheniformis strain SSA 61 adapt to salt stress.

    PubMed

    Paul, Sangeeta; Aggarwal, Chetana; Thakur, Jyoti Kumar; Bandeppa, G S; Khan, Md Aslam; Pearson, Lauren M; Babnigg, Gyorgy; Giometti, Carol S; Joachimiak, Andrzej

    2015-04-01

    Bacillus licheniformis strain SSA 61, originally isolated from Sambhar salt lake, was observed to grow even in the presence of 25 % salt stress. Osmoadaptive mechanisms of this halotolerant B. licheniformis strain SSA 61, for long-term survival and growth under salt stress, were determined. Proline was the preferentially accumulated compatible osmolyte. There was also increased accumulation of antioxidants ascorbic acid and glutathione. Among the different antioxidative enzymes assayed, superoxide dismutase played the most crucial role in defense against salt-induced stress in the organism. Adaptation to stress by the organism involved modulation of cellular physiology at various levels. There was enhanced expression of known proteins playing essential roles in stress adaptation, such as chaperones DnaK and GroEL, and general stress protein YfkM and polynucleotide phosphorylase/polyadenylase. Proteins involved in amino acid biosynthetic pathway, ribosome structure, and peptide elongation were also overexpressed. Salt stress-induced modulation of expression of enzymes involved in carbon metabolism was observed. There was up-regulation of a number of enzymes involved in generation of NADH and NADPH, indicating increased cellular demand for both energy and reducing power. PMID:25561404

  9. Physiological framework for adaptation of stomata to CO2 from glacial to future concentrations

    PubMed Central

    Franks, Peter J.; Leitch, Ilia J.; Ruszala, Elizabeth M.; Hetherington, Alistair M.; Beerling, David J.

    2012-01-01

    In response to short-term fluctuations in atmospheric CO2 concentration, ca, plants adjust leaf diffusive conductance to CO2, gc, via feedback regulation of stomatal aperture as part of a mechanism for optimizing CO2 uptake with respect to water loss. The operational range of this elaborate control mechanism is determined by the maximum diffusive conductance to CO2, gc(max), which is set by the size (S) and density (number per unit area, D) of stomata on the leaf surface. Here, we show that, in response to long-term exposure to elevated or subambient ca, plants alter gc(max) in the direction of the short-term feedback response of gc to ca via adjustment of S and D. This adaptive feedback response to ca, consistent with long-term optimization of leaf gas exchange, was observed in four species spanning a diverse taxonomic range (the lycophyte Selaginella uncinata, the fern Osmunda regalis and the angiosperms Commelina communis and Vicia faba). Furthermore, using direct observation as well as flow cytometry, we observed correlated increases in S, guard cell nucleus size and average apparent 1C DNA amount in epidermal cell nuclei with increasing ca, suggesting that stomatal and leaf adaptation to ca is linked to genome scaling. PMID:22232765

  10. Physiological framework for adaptation of stomata to CO2 from glacial to future concentrations.

    PubMed

    Franks, Peter J; Leitch, Ilia J; Ruszala, Elizabeth M; Hetherington, Alistair M; Beerling, David J

    2012-02-19

    In response to short-term fluctuations in atmospheric CO(2) concentration, c(a), plants adjust leaf diffusive conductance to CO(2), g(c), via feedback regulation of stomatal aperture as part of a mechanism for optimizing CO(2) uptake with respect to water loss. The operational range of this elaborate control mechanism is determined by the maximum diffusive conductance to CO(2), g(c(max)), which is set by the size (S) and density (number per unit area, D) of stomata on the leaf surface. Here, we show that, in response to long-term exposure to elevated or subambient c(a), plants alter g(c(max)) in the direction of the short-term feedback response of g(c) to c(a) via adjustment of S and D. This adaptive feedback response to c(a), consistent with long-term optimization of leaf gas exchange, was observed in four species spanning a diverse taxonomic range (the lycophyte Selaginella uncinata, the fern Osmunda regalis and the angiosperms Commelina communis and Vicia faba). Furthermore, using direct observation as well as flow cytometry, we observed correlated increases in S, guard cell nucleus size and average apparent 1C DNA amount in epidermal cell nuclei with increasing c(a), suggesting that stomatal and leaf adaptation to c(a) is linked to genome scaling. PMID:22232765

  11. RNA Sequencing of Populus x canadensis Roots Identifies Key Molecular Mechanisms Underlying Physiological Adaption to Excess Zinc

    PubMed Central

    Ariani, Andrea; Di Baccio, Daniela; Romeo, Stefania; Lombardi, Lara; Andreucci, Andrea; Lux, Alexander; Horner, David Stephen; Sebastiani, Luca

    2015-01-01

    Populus x canadensis clone I-214 exhibits a general indicator phenotype in response to excess Zn, and a higher metal uptake in roots than in shoots with a reduced translocation to aerial parts under hydroponic conditions. This physiological adaptation seems mainly regulated by roots, although the molecular mechanisms that underlie these processes are still poorly understood. Here, differential expression analysis using RNA-sequencing technology was used to identify the molecular mechanisms involved in the response to excess Zn in root. In order to maximize specificity of detection of differentially expressed (DE) genes, we consider the intersection of genes identified by three distinct statistical approaches (61 up- and 19 down-regulated) and validate them by RT-qPCR, yielding an agreement of 93% between the two experimental techniques. Gene Ontology (GO) terms related to oxidation-reduction processes, transport and cellular iron ion homeostasis were enriched among DE genes, highlighting the importance of metal homeostasis in adaptation to excess Zn by P. x canadensis clone I-214. We identified the up-regulation of two Populus metal transporters (ZIP2 and NRAMP1) probably involved in metal uptake, and the down-regulation of a NAS4 gene involved in metal translocation. We identified also four Fe-homeostasis transcription factors (two bHLH38 genes, FIT and BTS) that were differentially expressed, probably for reducing Zn-induced Fe-deficiency. In particular, we suggest that the down-regulation of FIT transcription factor could be a mechanism to cope with Zn-induced Fe-deficiency in Populus. These results provide insight into the molecular mechanisms involved in adaption to excess Zn in Populus spp., but could also constitute a starting point for the identification and characterization of molecular markers or biotechnological targets for possible improvement of phytoremediation performances of poplar trees. PMID:25671786

  12. Physiological adaptations to prolonged fasting in the overwintering striped skunk (Mephitis mephitis).

    PubMed

    Mustonen, Anne-Mari; Bowman, Jeff; Sadowski, Carrie; Nituch, Larissa A; Bruce, Laura; Halonen, Toivo; Puukka, Katri; Rouvinen-Watt, Kirsti; Aho, Jari; Nieminen, Petteri

    2013-12-01

    Wintertime physiology of captive striped skunks (Mephitis mephitis) in response to cold ambient temperature (Ta) and fasting was investigated with body temperature (Tb) and activity recordings and analyses of hematology, plasma biochemistry and tissue fatty acids (FA). After 105 days of food deprivation, the skunks were in phase II of fasting indicated by the elevated plasma nonesterified FA and glycerol but no accumulation of nitrogen end products. Shorter-chain saturated and monounsaturated FA together with C18-20 n-3 polyunsaturated FA were preferentially mobilized. Individual amino acids responded to fasting in a complex manner, while essential and nonessential amino acid sums remained stable. Increases in hemoglobin and hematocrit suggested dehydration. The activity levels were lower in mid-January-early March, and the activity bouts were mostly displayed between 17:00-23:00 h. Daily torpor was observed in two females with 29 and 46 bouts. The deepest torpor (Tb<31 °C) occurred between dawn and early afternoon and lasted for 3.3 ± 0.18 h. The average minimum Tb was 29.2 ± 0.15 °C and the lowest recorded Tb was 25.8 °C. There was significant relation between the average 24-h Tb and Ta. Increases in wintertime Ta, as predicted by climate change scenarios, could influence torpor patterns in the species. PMID:23981473

  13. Physiological and morphological adaptations in relation to water use efficiency in Mediterranean accessions of Solanum lycopersicum.

    PubMed

    Galmés, Jeroni; Conesa, Miquel Àngel; Ochogavía, Joan Manuel; Perdomo, Juan Alejandro; Francis, David M; Ribas-Carbó, Miquel; Savé, Robert; Flexas, Jaume; Medrano, Hipólito; Cifre, Josep

    2011-02-01

    The physiological traits underlying the apparent drought resistance of 'Tomàtiga de Ramellet' (TR) cultivars, a population of Mediterranean tomato cultivars with delayed fruit deterioration (DFD) phenotype and typically grown under non-irrigation conditions, are evaluated. Eight different tomato accessions were selected and included six TR accessions, one Mediterranean non-TR accession (NTR(M)) and a processing cultivar (NTR(O)). Among the TR accessions two leaf morphology types, normal divided leaves and potato-leaf, were selected. Plants were field grown under well-watered (WW) and water-stressed (WS) treatments, with 30 and 10% of soil water capacity, respectively. Accessions were clustered according to the leaf type and TR phenotype under WW and WS, respectively. Correlation among parameters under the different water treatments suggested that potential improvements in the intrinsic water-use efficiency (A(N)/g(s)) are possible without negative impacts on yield. Under WS TR accessions displayed higher A(N)/g(s), which was not due to differences in Rubisco-related parameters, but correlated with the ratio between the leaf mesophyll and stomatal conductances (g(m)/g(s)). The results confirm the existence of differential traits in the response to drought stress in Mediterranean accessions of tomato, and demonstrate that increases in the g(m)/g(s) ratio would allow improvements in A(N)/g(s) in horticultural crops. PMID:20955222

  14. Growth, physiological adaptation, and gene expression analysis of two Egyptian rice cultivars under salt stress.

    PubMed

    Mekawy, Ahmad Mohammad M; Assaha, Dekoum V M; Yahagi, Hiroyuki; Tada, Yuma; Ueda, Akihiro; Saneoka, Hirofumi

    2015-02-01

    Abiotic stressors, such as high salinity, greatly affect plant growth. In an attempt to explore the mechanisms underlying salinity tolerance, physiological parameters of two local Egyptian rice (Oryza sativa L.) cultivars, Sakha 102 and Egyptian Yasmine, were examined under 50 mM NaCl stress for 14 days. The results indicate that Egyptian Yasmine is relatively salt tolerant compared to Sakha 102, and this was evident in its higher dry mass production, lower leaf Na(+) levels, and enhanced water conservation under salt stress conditions. Moreover, Egyptian Yasmine exhibited lower Na(+)/K(+) ratios in all tissues examined under salinity stress. The ability to maintain such traits seemed to differ in the leaves and roots of Egyptian Yasmine, and the root K(+) content was much higher in Egyptian Yasmine than in Sakha 102. In order to understand the basis for these differences, we studied transcript levels of genes encoding Na(+) and K(+) transport proteins in different tissues. In response to salinity stress, Egyptian Yasmine showed induction of expression of some membrane transporter/channel genes that may contribute to Na(+) exclusion from the shoots (OsHKT1;5), limiting excess Na(+) entry into the roots (OsLti6b), K(+) uptake (OsAKT1), and reduced expression of a Na(+) transporter gene (OsHKT2;1). Therefore, the active regulation of genes related to Na(+) transport at the transcription level may be involved in salt tolerance mechanisms of Egyptian Yasmine, and these mechanisms offer the promise of improved salinity stress tolerance in local Egyptian rice genotypes. PMID:25532120

  15. Physiological Adaptations and Countermeasures Associated with Long-Duration Space Flights

    NASA Technical Reports Server (NTRS)

    Tipton, C. M.; Hargens, A. R.; Baldwin, K. M.; Schneider, V.; Convertino, V. A.; Kozlovskaya, I.; Wade, Charles E. (Technical Monitor)

    1994-01-01

    On earth, the presence of gravity imposes weight-bearing gradients on tissues which influence the functions of multiple integrative systems. On the other hand, conditions of actual or simulated microgravity can modify and/or nullify these gradients and subsequently alter structure and function. The purpose of this symposium is to discuss the results from short-term Shuttle flights, long term Skylab or Mir missions, or long-term ground based experiments which indicate or suggest that performance has been or could be compromised in space missions of long durations (>one year) or with space tasks (e.g. building space stations) with the goal of identifying countermeasures that could minimize or eliminate the expected anatomical and physiological consequences. After an overview by C. Tipton from the U. Arizona, the countermeasures necessary for the fluid shifts and select functions of the cardiovascular system will be discussed by A. Hargens from NASA Ames Research Center. He will be followed by K. Baldwin of the U. California at Irvine who will discuss the countermeasures needed to prevent the changes that alter the structure, function and control of skeletal muscles. Since changes in bone mass with microgravity are a major concern of NASA, V. Schneider from NASA Headquarters will present data and the countermeasures for bone. Although the results are limited, the changes in the endocrine and immune system deserve mentioning and C. Tipton will assume this responsibility. V. Convertino from the Air Force School of Aerospace Medicine has the challenge of discussing the role, importance, and the specificity of exercise as an effective countermeasure while I. Kozlovskaya from Moscow will elaborate on the Russian experiences with past countermeasures and provide a viewpoint on future ones. After the brief (25 min.) presentations, the speakers will assemble as a panel to discuss the issues raised and the concerns of the audience.

  16. Physiological and performance adaptations of elite Greco-Roman wrestlers during a one-day tournament.

    PubMed

    Barbas, Ioannis; Fatouros, Ioannis G; Douroudos, Ioannis I; Chatzinikolaou, Athanasios; Michailidis, Yiannis; Draganidis, Dimitrios; Jamurtas, Athanasios Z; Nikolaidis, Michalis G; Parotsidis, Charalabos; Theodorou, Anastasios A; Katrabasas, Ioannis; Margonis, Konstantinos; Papassotiriou, Ioannis; Taxildaris, Kyriakos

    2011-07-01

    The aim of this study was to determine the effects of a simulated one-day Greco-Roman wrestling tournament on selected performance and inflammatory status indices. Twelve competitive wrestlers (22.1 ± 1.3 years) completed five matches according to the official Olympic wrestling tournament regulations following a ~6% weight loss. Performance measurements, muscle damage assessment, and blood sampling were performed before and following each match. Performance and inflammatory markers were not affected by weight loss. Mean wrestling heart rate reached ~85% of maximal and lactate concentration exceeded 17 mM. Fatigue rating demonstrated a progressive rise (P < 0.05) throughout the tournament, peaking in match 4. Performance demonstrated a progressive deterioration (P < 0.05) throughout the tournament, especially in the last two matches (P < 0.05), with upper-body measures exhibiting a greater decline (P < 0.05) and remaining below baseline (P < 0.05) until the end of the tournament. Muscle damage markers increased during the course of the tournament with upper limbs affected more. Creatine kinase activity, CRP levels, IL-6 concentration, and leukocyte counts increased (P < 0.05) progressively throughout the tournament, peaking in the last two matches. Cortisol, epinephrine and norepinephrine increased (P < 0.05) after each match, but testosterone declined (P < 0.05) progressively, reaching a nadir before the last match. This inflammatory response was accompanied by a marked increase (p < 0.05) in lipid peroxidation, protein oxidation, and antioxidant status markers indicating the development of oxidative stress. These results suggest that a one-day wrestling tournament may induce significant physiological demands on wrestlers that may adversely affect their performance and inflammatory status especially during the later stages of the tournament. PMID:21161266

  17. Physiological performance of warm-adapted marine ectotherms: Thermal limits of mitochondrial energy transduction efficiency.

    PubMed

    Martinez, Eloy; Hendricks, Eric; Menze, Michael A; Torres, Joseph J

    2016-01-01

    Thermal regimes in aquatic systems have profound implications for the physiology of ectotherms. In particular, the effect of elevated temperatures on mitochondrial energy transduction in tropical and subtropical teleosts may have profound consequences on organismal performance and population viability. Upper and lower whole-organism critical temperatures for teleosts suggest that subtropical and tropical species are not susceptible to the warming trends associated with climate change, but sub-lethal effects on energy transduction efficiency and population dynamics remain unclear. The goal of the present study was to compare the thermal sensitivity of processes associated with mitochondrial energy transduction in liver mitochondria from the striped mojarra (Eugerres plumieri), the whitemouth croaker (Micropogonias furnieri) and the palometa (Trachinotus goodei), to those of the subtropical pinfish (Lagodon rhomboides) and the blue runner (Caranx crysos). Mitochondrial function was assayed at temperatures ranging from 10 to 40°C and results obtained for both tropical and subtropical species showed a reduction in the energy transduction efficiency of the oxidative phosphorylation (OXPHOS) system in most species studied at temperatures below whole-organism critical temperature thresholds. Our results show a loss of coupling between O2 consumption and ATP production before the onset of the critical thermal maxima, indicating that elevated temperature may severely impact the yield of ATP production per carbon unit oxidized. As warming trends are projected for tropical regions, increasing water temperatures in tropical estuaries and coral reefs could impact long-term growth and reproductive performance in tropical organisms, which are already close to their upper thermal limit. PMID:26297983

  18. Regional physiological adaptation of the central nervous system deiodinases to iodine deficiency.

    PubMed

    Peeters, R; Fekete, C; Goncalves, C; Legradi, G; Tu, H M; Harney, J W; Bianco, A C; Lechan, R M; Larsen, P R

    2001-07-01

    The goal of the present investigation was to analyze the types 2 (D2) and 3 (D3) iodothyronine deiodinases in various structures within the central nervous system (CNS) in response to iodine deficiency. After 5-6 wk of low-iodine diet (LID) or LID + 2 microg potassium iodide/ml (LID + KI; control), rats' brains were processed for in situ hybridization histochemistry for D2 and D3 mRNA or dissected, frozen in liquid nitrogen, and processed for D2 and D3 activities. LID did not affect weight gain or serum triiodothyronine, but plasma thyroxine (T4) was undetectable. In the LID + KI animals, D3 activities were highest in the cerebral cortex (CO) and hippocampus (HI), followed by the olfactory bulb and was lowest in cerebellum (CE). Iodine deficiency decreased D3 mRNA expression in all CNS regions, and these changes were accompanied by three- to eightfold decreases in D3 activity. In control animals, D2 activity in the medial basal hypothalamus (MBH) was similar to that in pituitary gland. Of the CNS D2-expressing regions analyzed, the two most responsive to iodine deficiency were the CO and HI, in which an approximately 20-fold increase in D2 activity occurred. Other regions, i.e., CE, lateral hypothalamus, MBH, and pituitary gland, showed smaller increases. The distribution of and changes in D2 mRNA were similar to those of D2 activity. Our results indicate that decreases in the expression of D3 and increases in D2 are an integral peripheral component of the physiological response of the CNS to iodine deficiency. PMID:11404222

  19. Effects of recombinant bovine somatotropin during the periparturient period on innate and adaptive immune responses, systemic inflammation, and metabolism of dairy cows.

    PubMed

    Silva, P R B; Machado, K S; Da Silva, D N Lobão; Moraes, J G N; Keisler, D H; Chebel, R C

    2015-07-01

    The aim of this experiment was to determine effects of treating peripartum dairy cows with body condition score ?3.75 with recombinant bovine somatotropin (rbST) on immune, inflammatory, and metabolic responses. Holstein cows (253±1d of gestation) were assigned randomly to 1 of 3 treatments: untreated control (n=53), rbST87.5 (n=56; 87.5mg of rbST), and rbST125 (n=57; 125mg of rbST). Cows in the rbST87.5 and rbST125 treatments received rbST weekly from -21 to 28d relative to calving. Growth hormone, insulin-like growth factor 1, haptoglobin, tumor necrosis factor ?, nonesterified fatty acids, ?-hydroxybutyrate, glucose, and cortisol concentrations were determined weekly from -21 to 21d relative to calving. Blood sampled weekly from -14 to 21d relative to calving was used for hemogram and polymorphonuclear leukocyte (PMNL) expression of adhesion molecules, phagocytosis, and oxidative burst. Cows were vaccinated with ovalbumin at -21, -7, and 7d relative to calving, and blood was collected weekly from -21 to 21d relative to calving to determine IgG anti-ovalbumin concentrations. A subsample of cows had liver biopsied -21, -7, and 7d relative to calving to determine total lipids, triglycerides, and glycogen content. Growth hormone concentrations prepartum (control=11.0±1.2, rbST87.5=14.1±1.2, rbST125=15.1±1.3ng/mL) and postpartum (control=14.4±1.1, rbST87.5=17.8±1.2, rbST125=21.8±1.1ng/mL) were highest for rbST125 cows. Cows treated with rbST had higher insulin-like growth factor 1 concentrations than control cows (control=110.5±4.5, rbST87.5=126.2±4.5, rbST125=127.2±4.5ng/mL) only prepartum. Intensity of L-selectin expression was higher for rbST125 than for control and rbST87.5 cows [control=3,590±270, rbST87.5=3,279±271, rbST125=4,371±279 geometric mean fluorescence intensity (GMFI)] in the prepartum period. The PMNL intensities of phagocytosis (control=3,131±130, rbST87.5=3,391±133, rbST125=3,673±137 GMFI) and oxidative burst (control=9,588±746, rbST87.5=11,238±761, rbST125=12,724±781 GMFI) were higher for rbST125 cows than for control cows during the prepartum period. Concentrations of serum IgG anti-ovalbumin tended to be higher for rbST125 cows than for control cows (control=0.75±0.11, rbST87.5=0.94±0.10, rbST125=1.11±0.11 optical density) in the prepartum period. Haptoglobin concentration was significantly reduced 7d postpartum for rbST125 treatment compared with control and rbST87.5 treatments (control=2.74±0.28, rbST87.5=2.81±0.28, rbST125=1.87±0.28 optical density). Although treatment tended to affect postpartum ?-hydroxybutyrate (control=747.5±40.2, rbST87.5=753.2±40.1, rbST125=648.8±39.7 µmol/L), it did not affect liver contents of total lipids, triglycerides, or glycogen. Incidence of metritis among rbST125 cows was reduced compared with that in control cows (control=23.1, rbST87.5=18.0, rbST125=7.8%). Treatment of dairy cows with 125mg of rbST improved innate immune responses and IgG concentration, with limited effects on metabolism. PMID:25912866

  20. Explaining bathymetric diversity patterns in marine benthic invertebrates and demersal fishes: physiological contributions to adaptation of life at depth

    PubMed Central

    Brown, Alastair; Thatje, Sven

    2014-01-01

    Bathymetric biodiversity patterns of marine benthic invertebrates and demersal fishes have been identified in the extant fauna of the deep continental margins. Depth zonation is widespread and evident through a transition between shelf and slope fauna from the shelf break to 1000 m, and a transition between slope and abyssal fauna from 2000 to 3000 m; these transitions are characterised by high species turnover. A unimodal pattern of diversity with depth peaks between 1000 and 3000 m, despite the relatively low area represented by these depths. Zonation is thought to result from the colonisation of the deep sea by shallow-water organisms following multiple mass extinction events throughout the Phanerozoic. The effects of low temperature and high pressure act across hierarchical levels of biological organisation and appear sufficient to limit the distributions of such shallow-water species. Hydrostatic pressures of bathyal depths have consistently been identified experimentally as the maximum tolerated by shallow-water and upper bathyal benthic invertebrates at in situ temperatures, and adaptation appears required for passage to deeper water in both benthic invertebrates and demersal fishes. Together, this suggests that a hyperbaric and thermal physiological bottleneck at bathyal depths contributes to bathymetric zonation. The peak of the unimodal diversity–depth pattern typically occurs at these depths even though the area represented by these depths is relatively low. Although it is recognised that, over long evolutionary time scales, shallow-water diversity patterns are driven by speciation, little consideration has been given to the potential implications for species distribution patterns with depth. Molecular and morphological evidence indicates that cool bathyal waters are the primary site of adaptive radiation in the deep sea, and we hypothesise that bathymetric variation in speciation rates could drive the unimodal diversity–depth pattern over time. Thermal effects on metabolic-rate-dependent mutation and on generation times have been proposed to drive differences in speciation rates, which result in modern latitudinal biodiversity patterns over time. Clearly, this thermal mechanism alone cannot explain bathymetric patterns since temperature generally decreases with depth. We hypothesise that demonstrated physiological effects of high hydrostatic pressure and low temperature at bathyal depths, acting on shallow-water taxa invading the deep sea, may invoke a stress–evolution mechanism by increasing mutagenic activity in germ cells, by inactivating canalisation during embryonic or larval development, by releasing hidden variation or mutagenic activity, or by activating or releasing transposable elements in larvae or adults. In this scenario, increased variation at a physiological bottleneck at bathyal depths results in elevated speciation rate. Adaptation that increases tolerance to high hydrostatic pressure and low temperature allows colonisation of abyssal depths and reduces the stress–evolution response, consequently returning speciation of deeper taxa to the background rate. Over time this mechanism could contribute to the unimodal diversity–depth pattern. PMID:24118851

  1. Effect of prepartal ad libitum feeding of grass silage on transcriptional adaptations of the liver and subcutaneous adipose tissue in dairy cows during the periparturient period.

    PubMed

    Selim, S; Kokkonen, T; Taponen, J; Vanhatalo, A; Elo, K

    2015-08-01

    Prepartal energy overfeeding may predispose cows to a state of increased insulin resistance with greater lipolysis after parturition. The aim of the study was to evaluate the effects of prepartal overfeeding in terms of abundant grass silage ration on the liver and subcutaneous adipose tissue (SAT) gene expression around parturition. Sixteen multiparous Finnish Ayrshire dairy cows were fed ad libitum either grass silage [high energy, HE; 144 MJ/d of metabolizable energy (ME) intake, n=8] or a mixture of grass silage, wheat straw, and rapeseed meal [55:40:5 (CON), 109 MJ/d of ME, n=8] during the dry period (58.2±4.89 d, mean ± standard deviation). Tissue biopsies and blood samples were collected at -14 (±4.98), 1, and 7 d relative to the actual parturition date. The HE cows had greater total dry matter intake, ME intake, and ME balance during the dry period than the CON cows. Compared with CON, the increases in body weight and body condition score were greater in HE during the dry period. Milk yield during the first 2 wk of lactation was not different between the groups. Plasma glucose, nonesterified fatty acids, insulin, glucagon, and ?-hydroxybutyrate did not differ between the groups during the transition period. Dietary treatment did not affect hepatic triglyceride content; however, a delayed increase in hepatic total lipid content was observed in the HE cows at d 1 postpartum. Hepatic cytosolic phosphoenolpyruvate carboxykinase 1 mRNA expression was lower in HE than in CON at d 1 and 7 postpartum. Adiponectin receptor 1 and 2 mRNA abundance tended to be lower in SAT of HE than CON. Lower lipoprotein lipase, leptin, and stearoyl-coenzyme A desaturase mRNA abundances were observed at d 7 postpartum in SAT of the HE cows compared with the CON cows. We concluded that prepartal ad libitum feeding of grass silage may decrease insulin sensitivity and lipogenesis in SAT during peripartal period and may attenuate the increase of hepatic gluconeogenic capacity from propionate compared with a controlled-energy diet. PMID:26026764

  2. HIF-1-driven skeletal muscle adaptations to chronic hypoxia: molecular insights into muscle physiology.

    PubMed

    Favier, F B; Britto, F A; Freyssenet, D G; Bigard, X A; Benoit, H

    2015-12-01

    Skeletal muscle is a metabolically active tissue and the major body protein reservoir. Drop in ambient oxygen pressure likely results in a decrease in muscle cells oxygenation, reactive oxygen species (ROS) overproduction and stabilization of the oxygen-sensitive hypoxia-inducible factor (HIF)-1?. However, skeletal muscle seems to be quite resistant to hypoxia compared to other organs, probably because it is accustomed to hypoxic episodes during physical exercise. Few studies have observed HIF-1? accumulation in skeletal muscle during ambient hypoxia probably because of its transient stabilization. Nevertheless, skeletal muscle presents adaptations to hypoxia that fit with HIF-1 activation, although the exact contribution of HIF-2, I kappa B kinase and activating transcription factors, all potentially activated by hypoxia, needs to be determined. Metabolic alterations result in the inhibition of fatty acid oxidation, while activation of anaerobic glycolysis is less evident. Hypoxia causes mitochondrial remodeling and enhanced mitophagy that ultimately lead to a decrease in ROS production, and this acclimatization in turn contributes to HIF-1? destabilization. Likewise, hypoxia has structural consequences with muscle fiber atrophy due to mTOR-dependent inhibition of protein synthesis and transient activation of proteolysis. The decrease in muscle fiber area improves oxygen diffusion into muscle cells, while inhibition of protein synthesis, an ATP-consuming process, and reduction in muscle mass decreases energy demand. Amino acids released from muscle cells may also have protective and metabolic effects. Collectively, these results demonstrate that skeletal muscle copes with the energetic challenge imposed by O2 rarefaction via metabolic optimization. PMID:26298291

  3. Physiological and health-related adaptations to low-volume interval training: influences of nutrition and sex.

    PubMed

    Gibala, Martin J; Gillen, Jenna B; Percival, Michael E

    2014-11-01

    Interval training refers to the basic concept of alternating periods of relatively intense exercise with periods of lower-intensity effort or complete rest for recovery. Low-volume interval training refers to sessions that involve a relatively small total amount of exercise (i.e. ?10 min of intense exercise), compared with traditional moderate-intensity continuous training (MICT) protocols that are generally reflected in public health guidelines. In an effort to standardize terminology, a classification scheme was recently proposed in which the term 'high-intensity interval training' (HIIT) be used to describe protocols in which the training stimulus is 'near maximal' or the target intensity is between 80 and 100 % of maximal heart rate, and 'sprint interval training' (SIT) be used for protocols that involve 'all out' or 'supramaximal' efforts, in which target intensities correspond to workloads greater than what is required to elicit 100 % of maximal oxygen uptake (VO2max). Both low-volume SIT and HIIT constitute relatively time-efficient training strategies to rapidly enhance the capacity for aerobic energy metabolism and elicit physiological remodeling that resembles changes normally associated with high-volume MICT. Short-term SIT and HIIT protocols have also been shown to improve health-related indices, including cardiorespiratory fitness and markers of glycemic control in both healthy individuals and those at risk for, or afflicted by, cardiometabolic diseases. Recent evidence from a limited number of studies has highlighted potential sex-based differences in the adaptive response to SIT in particular. It has also been suggested that specific nutritional interventions, in particular those that can augment muscle buffering capacity, such as sodium bicarbonate, may enhance the adaptive response to low-volume interval training. PMID:25355187

  4. Cows Causing Global Warming

    E-print Network

    Hacker, Randi

    2008-08-06

    Broadcast Transcript: Remember when President Reagan blamed trees for air pollution? Well now the Japanese are blaming cows for global warming. Apparently, the methane emissions from burping cows account for 5% of all global greenhouse gases. Simple...

  5. Cow's milk and children

    MedlinePLUS

    Milk and children ... children over 1 year old to drink cow's milk. However, there's no scientific evidence that this is true. While most experts recommend not giving cow's milk to infants , it is safe to give milk ...

  6. Leap of faith: voluntary emersion behaviour and physiological adaptations to aerial exposure in a non-aestivating freshwater fish in response to aquatic hypoxia.

    PubMed

    Urbina, Mauricio A; Forster, Malcolm E; Glover, Chris N

    2011-05-01

    Lowland stream fauna in areas of intensive agriculture are increasingly under threat from anthropogenic activities leading to eutrophication and subsequent hypoxia. Survival of hypoxic episodes depends upon a combination of behavioural and physiological adaptations. Responses of inanga (Galaxias maculatus: Galaxiidae) to aquatic hypoxia were investigated in the laboratory. Contrary to expectation inanga did not display behaviour that might reduce energy expenditure during oxygen limitation, with swimming activity slightly, but significantly elevated relative to normoxia. Instead, as dissolved oxygen concentrations decreased, the fish moved higher in the water column, increased their swimming speed and exhibited aquatic surface respiration. Physiological changes such as enhanced opercular frequency were also noted. As hypoxia deepened inanga started to leap out of the water, emersing themselves on a floating platform. Once emersed, fish exhibited an enhanced oxygen consumption rate compared to hypoxic fish. Thus inanga appear better adapted to escape hypoxia (a behavioural adaptation) rather than tolerate it (physiological adaptation). The emersion strategy used for inanga in response to severe hypoxia is in agreement with their ability to take up more oxygen from the air than from hypoxic water and therefore may justify the potentially increased risks of desiccation and predation associated with leaving the water. PMID:21316378

  7. What's Mad Cow Disease?

    MedlinePLUS

    ... System How the Body Works Main Page What's Mad Cow Disease? KidsHealth > Kids > Q&A > Q & A > What's Mad Cow Disease? Print A A A Text Size What's in ... Do? You might have heard news reports about mad cow disease and wondered: What the heck is that? Mad ...

  8. Effect of selecting for “Robustness” on temperament in dairy cows 

    E-print Network

    Gibbons, Jennifer M.

    Increased rates of involuntary culling as a consequence of poorer health and fertility had led to the conclusion that dairy cows appear to be less “robust” or adaptable than in the past. A way to address these concerns ...

  9. Physiologic adaptation of man in space; Proceedings of the Seventh International Man in Space Symposium, Houston, TX, Feb. 10-13, 1986

    NASA Technical Reports Server (NTRS)

    Holland, Albert W. (editor)

    1987-01-01

    Topics discussed in this volume include space motion sickness, cardiovascular adaptation, fluid shifts, extravehicular activity, general physiology, perception, vestibular response modifications, vestibular physiology, and pharmacology. Papers are presented on the clinical characterization and etiology of space motion sickness, ultrasound techniques in space medicine, fluid shifts in weightlessness, Space Shuttle inflight and postflight fluid shifts measured by leg volume changes, and the probability of oxygen toxicity in an 8-psi space suit. Consideration is also given to the metabolic and hormonal status of crewmembers in short-term space flights, adaptive changes in perception of body orientation and mental image rotation in microgravity, the effects of a visual-vestibular stimulus on the vestibulo-ocular reflex, rotation tests in the weightless phase of parabolic flight, and the mechanisms of antimotion sickness drugs.

  10. Physiological basis for high CO2 tolerance in marine ectothermic animals: pre-adaptation through lifestyle and ontogeny?

    NASA Astrophysics Data System (ADS)

    Melzner, F.; Gutowska, M. A.; Langenbuch, M.; Dupont, S.; Lucassen, M.; Thorndyke, M. C.; Bleich, M.; Pörtner, H.-O.

    2009-10-01

    Future ocean acidification has the potential to adversely affect many marine organisms. A growing body of evidence suggests that many species could suffer from reduced fertilization success, decreases in larval- and adult growth rates, reduced calcification rates, and even mortality when being exposed to near-future levels (year 2100 scenarios) of ocean acidification. Little research focus is currently placed on those organisms/taxa that might be less vulnerable to the anticipated changes in ocean chemistry; this is unfortunate, as the comparison of more vulnerable to more tolerant physiotypes could provide us with those physiological traits that are crucial for ecological success in a future ocean. Here, we attempt to summarize some ontogenetic and lifestyle traits that lead to an increased tolerance towards high environmental pCO2. In general, marine ectothermic metazoans with an extensive extracellular fluid volume may be less vulnerable to future acidification as their cells are already exposed to much higher pCO2 values (0.1 to 0.4 kPa, ca. 1000 to 3900 ?atm) than those of unicellular organisms and gametes, for which the ocean (0.04 kPa, ca. 400 ?atm) is the extracellular space. A doubling in environmental pCO2 therefore only represents a 10% change in extracellular pCO2 in some marine teleosts. High extracellular pCO2 values are to some degree related to high metabolic rates, as diffusion gradients need to be high in order to excrete an amount of CO2 that is directly proportional to the amount of O2 consumed. In active metazoans, such as teleost fish, cephalopods and many brachyuran crustaceans, exercise induced increases in metabolic rate require an efficient ion-regulatory machinery for CO2 excretion and acid-base regulation, especially when anaerobic metabolism is involved and metabolic protons leak into the extracellular space. These ion-transport systems, which are located in highly developed gill epithelia, form the basis for efficient compensation of pH disturbances during exposure to elevated environmental pCO2. Compensation of extracellular acid-base status in turn may be important in avoiding metabolic depression. So far, maintained "performance" at higher seawater pCO2 (>0.3 to 0.6 kPa) has only been observed in adults/juveniles of active, high metabolic species with a powerful ion regulatory apparatus. However, while some of these taxa are adapted to cope with elevated pCO2 during their regular embryonic development, gametes, zygotes and early embryonic stages, which lack specialized ion-regulatory epithelia, may be the true bottleneck for ecological success - even of the more tolerant taxa. Our current understanding of which marine animal taxa will be affected adversely in their physiological and ecological fitness by projected scenarios of anthropogenic ocean acidification is quite incomplete. While a growing amount of empirical evidence from CO2 perturbation experiments suggests that several taxa might react quite sensitively to ocean acidification, others seem to be surprisingly tolerant. However, there is little mechanistic understanding on what physiological traits are responsible for the observed differential sensitivities (see reviews of Seibel and Walsh, 2003; Pörtner et al., 2004; Fabry et al., 2008; Pörtner, 2008). This leads us to the first very basic question of how to define general CO2 tolerance on the species level.

  11. Physiological and morphological adaptations of herbaceous perennial legumes allow differential access to sources of varyingly soluble phosphate.

    PubMed

    Pang, Jiayin; Yang, Jiyun; Lambers, Hans; Tibbett, Mark; Siddique, Kadambot H M; Ryan, Megan H

    2015-08-01

    The aim of this study was to investigate the capacity of three perennial legume species to access sources of varyingly soluble phosphorus (P) and their associated morphological and physiological adaptations. Two Australian native legumes with pasture potential (Cullen australasicum and Kennedia prostrata) and Medicago sativa cv. SARDI 10 were grown in sand under two P levels (6 and 40?µg P g(-1) ) supplied as Ca(H2 PO4 )2 ·H2 O (Ca-P, highly soluble, used in many fertilizers) or as one of three sparingly soluble forms: Ca10 (OH)2 (PO4 )6 (apatite-P, found in relatively young soils; major constituent of rock phosphate), C6 H6 O24 P6 Na12 (inositol-P, the most common form of organic P in soil) and FePO4 (Fe-P, a poorly-available inorganic source of P). All species grew well with soluble P. When 6?µg P g(-1) was supplied as sparingly soluble P, plant dry weight (DW) and P uptake were very low for C. australasicum and M. sativa (0.1-0.4?g DW) with the exception of M. sativa supplied with apatite-P (1.5?g). In contrast, K. prostrata grew well with inositol-P (1.0?g) and Fe-P (0.7?g), and even better with apatite-P (1.7?g), similar to that with Ca-P (1.9?g). Phosphorus uptake at 6?µg P g(-1) was highly correlated with total root length, total rhizosphere carboxylate content and total rhizosphere acid phosphatase (EC 3.1.3.2) activity. These findings provide strong indications that there are opportunities to utilize local Australian legumes in low P pasture systems to access sparingly soluble soil P and increase perennial legume productivity, diversity and sustainability. PMID:25291346

  12. Adaptation of the Hydrocarbonoclastic Bacterium Alcanivorax borkumensis SK2 to Alkanes and Toxic Organic Compounds: a Physiological and Transcriptomic Approach

    PubMed Central

    Naether, Daniela J.; Slawtschew, Slavtscho; Stasik, Sebastian; Engel, Maria; Olzog, Martin; Wick, Lukas Y.; Timmis, Kenneth N.

    2013-01-01

    The marine hydrocarbonoclastic bacterium Alcanivorax borkumensis is able to degrade mixtures of n-alkanes as they occur in marine oil spills. However, investigations of growth behavior and physiology of these bacteria when cultivated with n-alkanes of different chain lengths (C6 to C30) as the substrates are still lacking. Growth rates increased with increasing alkane chain length up to a maximum between C12 and C19, with no evident difference between even- and odd-numbered chain lengths, before decreasing with chain lengths greater than C19. Surface hydrophobicity of alkane-grown cells, assessed by determination of the water contact angles, showed a similar pattern, with maximum values associated with growth rates on alkanes with chain lengths between C11 and C19 and significantly lower values for cells grown on pyruvate. A. borkumensis was found to incorporate and modify the fatty acid intermediates generated by the corresponding n-alkane degradation pathway. Cells grown on distinct n-alkanes proved that A. borkumensis is able to not only incorporate but also modify fatty acid intermediates derived from the alkane degradation pathway. Comparing cells grown on pyruvate with those cultivated on hexadecane in terms of their tolerance toward two groups of toxic organic compounds, chlorophenols and alkanols, representing intensely studied organic compounds, revealed similar tolerances toward chlorophenols, whereas the toxicities of different n-alkanols were significantly reduced when hexadecane was used as a carbon source. As one adaptive mechanism of A. borkumensis to these toxic organic solvents, the activity of cis-trans isomerization of unsaturated fatty acids was proven. These findings could be verified by a detailed transcriptomic comparison between cultures grown on hexadecane and pyruvate and including solvent stress caused by the addition of 1-octanol as the most toxic intermediate of n-alkane degradation. PMID:23645199

  13. Adaptation of the hydrocarbonoclastic bacterium Alcanivorax borkumensis SK2 to alkanes and toxic organic compounds: a physiological and transcriptomic approach.

    PubMed

    Naether, Daniela J; Slawtschew, Slavtscho; Stasik, Sebastian; Engel, Maria; Olzog, Martin; Wick, Lukas Y; Timmis, Kenneth N; Heipieper, Hermann J

    2013-07-01

    The marine hydrocarbonoclastic bacterium Alcanivorax borkumensis is able to degrade mixtures of n-alkanes as they occur in marine oil spills. However, investigations of growth behavior and physiology of these bacteria when cultivated with n-alkanes of different chain lengths (C6 to C30) as the substrates are still lacking. Growth rates increased with increasing alkane chain length up to a maximum between C12 and C19, with no evident difference between even- and odd-numbered chain lengths, before decreasing with chain lengths greater than C19. Surface hydrophobicity of alkane-grown cells, assessed by determination of the water contact angles, showed a similar pattern, with maximum values associated with growth rates on alkanes with chain lengths between C11 and C19 and significantly lower values for cells grown on pyruvate. A. borkumensis was found to incorporate and modify the fatty acid intermediates generated by the corresponding n-alkane degradation pathway. Cells grown on distinct n-alkanes proved that A. borkumensis is able to not only incorporate but also modify fatty acid intermediates derived from the alkane degradation pathway. Comparing cells grown on pyruvate with those cultivated on hexadecane in terms of their tolerance toward two groups of toxic organic compounds, chlorophenols and alkanols, representing intensely studied organic compounds, revealed similar tolerances toward chlorophenols, whereas the toxicities of different n-alkanols were significantly reduced when hexadecane was used as a carbon source. As one adaptive mechanism of A. borkumensis to these toxic organic solvents, the activity of cis-trans isomerization of unsaturated fatty acids was proven. These findings could be verified by a detailed transcriptomic comparison between cultures grown on hexadecane and pyruvate and including solvent stress caused by the addition of 1-octanol as the most toxic intermediate of n-alkane degradation. PMID:23645199

  14. Biochemical and Physiological Adaptations

    E-print Network

    Angilletta, Michael

    life occurs in just about every environment on our planet, spanning an amazingly broad range and regulation impose costs, often expressed as trade-offs with other traits that affect fit- ness. By analyzing in a specifiedenvironment.Thisrelationshipcanbeusedto find the phenotype that maximizes fitness (the optimal phenotype

  15. The role of oxidative, inflammatory and neuroendocrinological systems during exercise stress in athletes: implications of antioxidant supplementation on physiological adaptation during intensified physical training.

    PubMed

    Slattery, Katie; Bentley, David; Coutts, Aaron J

    2015-04-01

    During periods of intensified physical training, reactive oxygen species (ROS) release may exceed the protective capacity of the antioxidant system and lead to dysregulation within the inflammatory and neuroendocrinological systems. Consequently, the efficacy of exogenous antioxidant supplementation to maintain the oxidative balance in states of exercise stress has been widely investigated. The aim of this review was to (1) collate the findings of prior research on the effect of intensive physical training on oxidant-antioxidant balance; (2) summarise the influence of antioxidant supplementation on the reduction-oxidation signalling pathways involved in physiological adaptation; and (3) provide a synopsis on the interactions between the oxidative, inflammatory and neuroendocrinological response to exercise stimuli. Based on prior research, it is evident that ROS are an underlying aetiology in the adaptive process; however, the impact of antioxidant supplementation on physiological adaptation remains unclear. Equivocal results have been reported on the impact of antioxidant supplementation on exercise-induced gene expression. Further research is required to establish whether the interference of antioxidant supplementation consistently observed in animal-based and in vivo research extends to a practical sports setting. Moreover, the varied results reported within the literature may be due to the hormetic response of oxidative, inflammatory and neuroendocrinological systems to an exercise stimulus. The collective findings suggest that intensified physical training places substantial stress on the body, which can manifest as an adaptive or maladaptive physiological response. Additional research is required to determine the efficacy of antioxidant supplementation to minimise exercise-stress during intensive training and promote an adaptive state. PMID:25398224

  16. Physiological basis for high CO2 tolerance in marine ectothermic animals: pre-adaptation through lifestyle and ontogeny?

    NASA Astrophysics Data System (ADS)

    Melzner, F.; Gutowska, M. A.; Langenbuch, M.; Dupont, S.; Lucassen, M.; Thorndyke, M. C.; Bleich, M.; Pörtner, H.-O.

    2009-05-01

    Future ocean acidification has the potential to adversely affect many marine organisms. A growing body of evidence suggests that many species could suffer from reduced fertilization success, decreases in larval- and adult growth rates, reduced calcification rates, metabolic depression and even mortality when being exposed to near-future levels (year 2100 scenarios) of ocean acidification. Little research focus is currently placed on those organisms/taxa that might be less vulnerable to the anticipated changes in ocean chemistry; this is unfortunate, as the comparison of more vulnerable to more tolerant physiotypes could provide us with those physiological traits that are crucial for ecological success in a future ocean. Here, we attempt to summarize some ontogenetic and lifestyle traits that lead to an increased tolerance towards high environmental pCO2. In general, marine ectothermic metazoans with an extensive extracellular fluid volume may be less vulnerable to future acidification as their cells are already exposed to much higher pCO2 values (0.1 to 0.4 kPa, 1000 to 4000 ?atm) than those of unicellular organisms and gametes, for which the ocean (0.04 kPa, 400 ?atm) is the extracellular space. A doubling in environmental pCO2 therefore only represents a 10% change in extracellular CO2 in some marine teleosts. High extracellular pCO2 values are to some degree related to high metabolic rates, as diffusion gradients need to be high in order to excrete an amount of CO2 that is directly proportional to the amount of O2 consumed. In active metazoans, such as teleost fish, cephalopods and many brachyuran crustaceans, exercise induced increases in metabolic rate require an efficient ion-regulatory machinery for CO2 excretion and acid-base regulation, especially when anaerobic metabolism is involved and metabolic protons leak into the extracellular space. These ion-transport systems, which are located in highly developed gill epithelia, form the basis for efficient compensation of pH disturbances during exposure to elevated environmental pCO2. Compensation of extracellular acid-base status in turn may be extremely important in avoiding metabolic depression. So far, maintained "performance" at higher seawater pCO2 (>0.3 to 0.6 kPa) has only been observed in adults/juveniles of active, high metabolic species with a powerful ion regulatory apparatus. However, while some of these taxa are adapted to cope with elevated pCO2 during their regular embryonic development, unicellular gametes, which lack specialized ion-regulatory epithelia, may be the true bottleneck for ecological success - even of the more tolerant taxa.

  17. Adaptive Calibration of Children's Physiological Responses to Family Stress: The Utility of Evolutionary Developmental Theory--Comment on Del Giudice et al. (2012) and Sturge-Apple et al. (2012)

    ERIC Educational Resources Information Center

    Bugental, Daphne Blunt

    2012-01-01

    Children's physiological reactions to stress are presented from the broader theoretical perspective of adaptive calibration to the environment, as rooted in life history theory. Del Giudice, Hinnant, Ellis, and El-Sheikh (2012) focus on children's physiological responses to a stressful task as a consequence of their history of family stress.…

  18. Cow dung powder poisoning

    PubMed Central

    Sherfudeen, Khaja Mohideen; Kaliannan, Senthil Kumar; Dammalapati, Pavan Kumar

    2015-01-01

    Cow dung, which has germicidal property, was used in ancient days to clean living premises in South India. Nowadays, people are using commercially available synthetic cow dung powder. It is locally known as “saani powder” in Tamil Nadu. It is freely available in homes and is sometimes accidentally consumed by children. It is available in two colors - yellow and green. Cow dung powder poisoning is common in districts of Tamil Nadu such as Coimbatore, Tirupur, and Erode. We report two cases of yellow cow dung powder poisoning from our hospital.

  19. Dissecting the COW

    SciTech Connect

    Linstadt, E.

    1985-04-01

    The COW, or Console On Wheels, is the primary operator interface to the SLC accelerator control system. A hardware and software description of the COW, a microcomputer based system with a color graphics display output and touch-panel and knob inputs, is given. The ease of development and expandability, due to both the modular nature of the hardware and the multitasking, interrupt driven software running in the COW, are described. Integration of the COW into the SLCNET communications network and SLC Control system is detailed.

  20. Dissecting the COW

    SciTech Connect

    Linstadt, E.

    1985-10-01

    The COW, or Console On Wheels, is the primary operator interface to the SLC accelerator control system. A hardware and software description of the COW, a microcomputer based system with a color graphics display output and touchpanel and knob inputs, is given. The ease of development and expandability, due to both the modular nature of the hardware and the multitasking, interrupt driven software running in the COW, are described. Integration of the COW into the SLCNET communications network and SLC Control system is detailed.

  1. Evaluating functional roles of phase resetting in generation of adaptive human bipedal walking with a physiologically based model of the spinal pattern generator.

    PubMed

    Aoi, Shinya; Ogihara, Naomichi; Funato, Tetsuro; Sugimoto, Yasuhiro; Tsuchiya, Kazuo

    2010-05-01

    The central pattern generators (CPGs) in the spinal cord strongly contribute to locomotor behavior. To achieve adaptive locomotion, locomotor rhythm generated by the CPGs is suggested to be functionally modulated by phase resetting based on sensory afferent or perturbations. Although phase resetting has been investigated during fictive locomotion in cats, its functional roles in actual locomotion have not been clarified. Recently, simulation studies have been conducted to examine the roles of phase resetting during human bipedal walking, assuming that locomotion is generated based on prescribed kinematics and feedback control. However, such kinematically based modeling cannot be used to fully elucidate the mechanisms of adaptation. In this article we proposed a more physiologically based mathematical model of the neural system for locomotion and investigated the functional roles of phase resetting. We constructed a locomotor CPG model based on a two-layered hierarchical network model of the rhythm generator (RG) and pattern formation (PF) networks. The RG model produces rhythm information using phase oscillators and regulates it by phase resetting based on foot-contact information. The PF model creates feedforward command signals based on rhythm information, which consists of the combination of five rectangular pulses based on previous analyses of muscle synergy. Simulation results showed that our model establishes adaptive walking against perturbing forces and variations in the environment, with phase resetting playing important roles in increasing the robustness of responses, suggesting that this mechanism of regulation may contribute to the generation of adaptive human bipedal locomotion. PMID:20217427

  2. Physiological Observations and Omics to Develop Personalized Sensormotor Adaptability Countermeasures Using Bed Rest and Space Flight Data

    NASA Technical Reports Server (NTRS)

    Mulavara, A. P.; Seidler, R. D.; Feiveson, A.; Oddsson, L.; Zanello, S.; Oman, C. M.; Ploutz-Snyder, L.; Peters, B.; Cohen, H. S.; Reschke, M.; Wood, S.; Bloomberg, J. J.

    2014-01-01

    Astronauts experience sensorimotor disturbances during the initial exposure to microgravity and during the re-adapation phase following a return to an earth-gravitational environment. These alterations may disrupt the ability to perform mission critical functional tasks requiring ambulation, manual control and gaze stability. Interestingly, astronauts who return from space flight show substantial differences in their abilities to readapt to a gravitational environment. The ability to predict the manner and degree to which individual astronauts would be affected would improve the effectiveness of countermeasure training programs designed to enhance sensorimotor adaptability. For such an approach to succeed, we must develop predictive measures of sensorimotor adaptability that will allow us to foresee, before actual space flight, which crewmembers are likely to experience the greatest challenges to their adaptive capacities. The goals of this project are to identify and characterize this set of predictive measures that include: 1) behavioral tests to assess sensory bias and adaptability quantified using both strategic and plastic-adaptive responses; 2) imaging to determine individual brain morphological and functional features using structural magnetic resonance imaging (MRI), diffusion tensor imaging, resting state functional connectivity MRI, and sensorimotor adaptation task-related functional brain activation; 3) genotype markers for genetic polymorphisms in Catechol-O-Methyl Transferase, Dopamine Receptor D2, Brain-derived neurotrophic factor and genetic polymorphism of alpha2-adrenergic receptor that play a role in the neural pathways underlying sensorimotor adaptation. We anticipate these predictive measures will be significantly correlated with individual differences in sensorimotor adaptability after long-duration space flight and an analog bed rest environment. We will be conducting a retrospective study leveraging data already collected from relevant ongoing/completed bed rest and space flight studies. These data will be combined with predictor metrics that will be collected prospectively - behavioral, brain imaging and genomic measures; from these returning subjects to build models for predicting post-mission (bed rest - non-astronauts or space flight - astronauts) adaptive capability as manifested in their outcome measures. Comparisons of model performance will allow us to better design and implement sensorimotor adaptability training countermeasures that are customized for each crewmember's sensory biases, adaptive capacity, brain structure and functional capacities, and genetic predispositions against decrements in post-mission adaptive capability. This ability will allow more efficient use of crew time during training and will optimize training prescriptions for astronauts to ensure expected outcomes.

  3. Temperature relations of aerial and aquatic physiological performance in a mid-intertidal limpet Cellana toreuma: adaptation to rapid changes in thermal stress during emersion.

    PubMed

    Huang, Xiongwei; Wang, Tifeng; Ye, Ziwen; Han, Guodong; Dong, Yunwei

    2015-01-01

    The physiological performance of a mid-intertidal limpet Cellana toreuma was determined to study the physiological adaptation of intertidal animals to rapid changes and extreme temperatures during emersion. The relationship between the Arrhenius breakpoint temperature (ABT) and in situ operative body temperature was studied to predict the possible impact of climate change on the species. The temperature coefficient (Q10) of emersed animals was higher than that of submersed animals and the ratio of aerial: aquatic heart rate rose with increasing temperature. The ABTs of submersed and emersed animals were 30.2 and 34.2°C, respectively. The heart rate and levels of molecular biomarkers (hsps, ampk?, ampk? and sirt1 mRNA) were determined in 48 h simulated semi-diurnal tides. There were no obvious changes of heart rate and gene expression during the transition between emersion and submersion at room temperature, although expressions of hsp70 and hsp90 were induced significantly after thermal stress. These results indicate that C. toreuma can effectively utilize atmospheric oxygen, and the higher Q10 and ABT of emersed animals are adaptations to the rapid change and extreme thermal stress during emersion. However, the in situ operative body temperature frequently exceeds the aerial ABT of C. toreuma, indicating the occurrence of large-scale mortality of C. toreuma in summer, and this species should be sensitive to increasing temperature in the scenario of climate change. PMID:24979525

  4. Physiology and the Biomedical Engineering Curriculum: Utilizing Emerging Instructional Technologies to Promote Development of Adaptive Expertise in Undergraduate Students

    ERIC Educational Resources Information Center

    Nelson, Regina K.

    2013-01-01

    A mixed-methods research study was designed to test whether undergraduate engineering students were better prepared to learn advanced topics in biomedical engineering if they learned physiology via a quantitative, concept-based approach rather than a qualitative, system-based approach. Experiments were conducted with undergraduate engineering…

  5. Does reduced precipitation trigger physiological and morphological drought adaptations in European beech (Fagus sylvatica L.)? Comparing provenances across a precipitation gradient.

    PubMed

    Knutzen, Florian; Meier, Ina Christin; Leuschner, Christoph

    2015-09-01

    Global warming and associated decreases in summer rainfall may threaten tree vitality and forest productivity in many regions of the temperate zone in the future. One option for forestry to reduce the risk of failure is to plant genotypes which combine high productivity with drought tolerance. Growth experiments with provenances from different climates indicate that drought exposure can trigger adaptive drought responses in temperate trees, but it is not well known whether and to what extent regional precipitation reduction can increase the drought resistance of a species. We conducted a common garden growth experiment with five European beech (Fagus sylvatica L.) populations from a limited region with pronounced precipitation heterogeneity (816-544?mm?year(-1)), where phylogenetically related provenances grew under small to large water deficits. We grew saplings of the five provenances at four soil moisture levels (dry to moist) and measured ?30 morphological (leaf and root properties, root?:?shoot ratio), physiological (leaf water status parameters, leaf conductance) and growth-related traits (above- and belowground productivity) with the aim to examine provenance differences in the drought response of morphological and physiological traits and to relate the responsiveness to precipitation at origin. Physiological traits were more strongly influenced by provenance (one-third of the studied traits), while structural traits were primarily affected by water availability in the experiment (two-thirds of the traits). The modulus of leaf tissue elasticity ? reached much higher values late in summer in plants from moist origins resulting in more rapid turgor loss and a higher risk of hydraulic failure upon drought. While experimental water shortage affected the majority of morphological and productivity-related traits in the five provenances, most parameters related to leaf water status were insensitive to water shortage. Thus, plant morphology, and root growth in particular, did respond to reduced water availability with higher phenotypic plasticity than did physiology. We conclude that beech provenances exposed to different precipitation regimes have developed some genotypic differences with respect to leaf water status regulation, but these adaptations are associated with only minor adaptation in plant morphology and they do not affect the growth rate of the saplings. PMID:26209617

  6. Grazing Soybean to Increase Voluntary Cow Traffic in a Pasture-based Automatic Milking System

    PubMed Central

    Clark, C. E. F.; Horadagoda, A.; Kerrisk, K. L.; Scott, V.; Islam, M. R.; Kaur, R.; Garcia, S. C.

    2014-01-01

    Pasture-based automatic milking systems (AMS) require cow traffic to enable cows to be milked. The interval between milkings can be manipulated by strategically allocating pasture. The current experiment investigated the effect of replacing an allocation of grazed pasture with grazed soybean (Glycine max) with the hypothesis that incorporating soybean would increase voluntary cow traffic and milk production. One hundred and eighty mixed age, primiparous and multiparous Holstein-Friesian/Illawarra cows were randomly assigned to two treatment groups (n = 90/group) with a 2×2 Latin square design. Each group was either offered treatments of kikuyu grass (Pennisetum clandestinum Hoach ex Chiov.) pasture (pasture) or soybean from 0900 h to 1500 h during the experimental period which consisted of 2 periods of 3 days following 5 days of training and adaptation in each period with groups crossing over treatments after the first period. The number of cows trafficking to each treatment was similar together with milk yield (mean ?18 L/cow/d) in this experiment. For the cows that arrived at soybean or pasture there were significant differences in their behaviour and consequently the number of cows exiting each treatment paddock. There was greater cow traffic (more cows and sooner) exiting pasture allocations. Cows that arrived at soybean stayed on the allocation for 25% more time and ate more forage (8.5 kg/cow/d/allocation) relative to pasture (4.7 kg/cow/d/allocation). Pasture cows predominantly replaced eating time with rumination. These findings suggest that replacing pasture with alternative grazeable forages provides no additional incentive to increase voluntary cow traffic to an allocation of feed in AMS. This work highlights the opportunity to increase forage intakes in AMS through the incorporation of alternative forages. PMID:25049970

  7. Implications of nutritional management for beef cow/calf systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The beef cattle industry relies on utilization of high forage diets to maintain the cow herd, develop replacement females, and stocker operations. Forage quantity and quality fluctuate with season and environmental conditions. Depending on class and physiological state of the animal, a grazed forage...

  8. Application of Physiological Self-Regulation and Adaptive Task Allocation Techniques for Controlling Operator Hazardous States of Awareness

    NASA Technical Reports Server (NTRS)

    Prinzel, Lawrence J., III; Pope, Alan T.; Freeman, Frederick G.

    2001-01-01

    Prinzel, Hadley, Freeman, and Mikulka found that adaptive task allocation significantly enhanced performance only when used at the endpoints of the task workload continuum (i.e., very low or high workload), but that the technique degraded performance if invoked during other levels of task demand. These researchers suggested that other techniques should be used in conjunction with adaptive automation to help minimize the onset of hazardous states of awareness (HSA) and keep the operator 'in-the-loop.' The paper reports on such a technique that uses psychophysiological self-regulation to modulate the level of task engagement. Eighteen participants were assigned to three groups (self-regulation, false feedback, and control) and performed a compensatory tracking task that was cycled between three levels of task difficulty on the basis of the electroencephalogram (EEG) record. Those participants who had received self-regulation training performed significantly better and reported lower NASA-TLX scores than participants in the false feedback and control groups. Furthermore, the false feedback and control groups had significantly more task allocations resulting in return-to-manual performance decrements and higher EEG difference scores. Theoretical and practical implications of these results for adaptive automation are discussed.

  9. Staphylococcal adaptation to diverse physiologic niches: an overview of transcriptomic and phenotypic changes in different biological environments.

    PubMed

    Dastgheyb, Sana S; Otto, Michael

    2015-12-01

    Host niches can differ strongly regarding, for example, oxygen tension, pH or nutrient availability. Staphylococcus aureus and other staphylococci are common colonizers of human epithelia as well as important human pathogens. The phenotypes that they show in different host environments, and the corresponding bacterial transcriptomes and proteomes, are currently under intense investigation. In this review, we examine the available literature describing staphylococcal phenotypes, such as expression of virulence factors, gross morphologic characteristics and growth patterns, in various physiological environments. Going forward, these studies will help researchers and clinicians to form an enhanced and more detailed picture of the interactions existing between the host and staphylococci as some of its most frequent colonizers and invaders. PMID:26584249

  10. Physiological and biomechanical adaptations to the cycle to run transition in Olympic triathlon: review and practical recommendations for training

    PubMed Central

    Millet, G.; Vleck, V.

    2000-01-01

    Current knowledge of the physiological, biomechanical, and sensory effects of the cycle to run transition in the Olympic triathlon (1.5 km, 10 km, 40 km) is reviewed and implications for the training of junior and elite triathletes are discussed. Triathlon running elicits hyperventilation, increased heart rate, decreased pulmonary compliance, and exercise induced hypoxaemia. This may be due to exercise intensity, ventilatory muscle fatigue, dehydration, muscle fibre damage, a shift in metabolism towards fat oxidation, and depleted glycogen stores after a 40 km cycle. The energy cost (CR) of running during the cycle to run transition is also increased over that of control running. The increase in CR varies from 1.6% to 11.6% and is a reflection of triathlete ability level. This increase may be partly related to kinematic alterations, but research suggests that most biomechanical parameters are unchanged. A more forward leaning trunk inclination is the most significant observation reported. Running pattern, and thus running economy, could also be influenced by sensorimotor perturbations related to the change in posture. Technical skill in the transition area is obviously very important. The conditions under which the preceding cycling section is performed—that is, steady state or stochastic power output, drafting or non-drafting—are likely to influence the speed of adjustment to transition. The extent to which a decrease in the average 10 km running speed occurs during competition must be investigated further. It is clear that the higher the athlete is placed in the field at the end of the bike section, the greater the importance to their finishing position of both a quick transition area time and optimal adjustment to the physiological demands of the cycle to run transition. The need for, and current methods of, training to prepare junior and elite triathletes for a better transition are critically reviewed in light of the effects of sequential cycle to run exercise. Key Words: triathlon; cycle to run transition; training; performance PMID:11049151

  11. MARKETING COWS FOR INCREASED PROFITABILITY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Substantial quantities of quality milk are the primary concern of dairy producers; however, approximately 33% of beef production in the U.S is from market dairy cows. Dairy cows are the class of cattle with the greatest violation of antibiotic residues. Additional feeding of market cows can increa...

  12. FEEDING AND MARKETING CULL COWS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sale of cull beef cows accounts for 15-25% of yearly gross revenues of cow-calf operations in the United States. Beef from market cows is widely used in the retail and food service sector in a variety of product forms, not all of which is ground. Producers should identify opportunities to add value...

  13. Physiological and cell morphology adaptation of Bacillus subtilis at near-zero specific growth rates: a transcriptome analysis.

    PubMed

    Overkamp, Wout; Ercan, Onur; Herber, Martijn; van Maris, Antonius J A; Kleerebezem, Michiel; Kuipers, Oscar P

    2015-02-01

    Nutrient scarcity is a common condition in nature, but the resulting extremely low growth rates (below 0.025?h(-1) ) are an unexplored research area in Bacillus subtilis. To understand microbial life in natural environments, studying the adaptation of B.?subtilis to near-zero growth conditions is relevant. To this end, a chemostat modified for culturing an asporogenous B.?subtilis?sigF mutant strain at extremely low growth rates (also named a retentostat) was set up, and biomass accumulation, culture viability, metabolite production and cell morphology were analysed. During retentostat culturing, the specific growth rate decreased to a minimum of 0.00006?h(-1) , corresponding to a doubling time of 470 days. The energy distribution between growth and maintenance-related processes showed that a state of near-zero growth was reached. Remarkably, a filamentous cell morphology emerged, suggesting that cell separation is impaired under near-zero growth conditions. To evaluate the corresponding molecular adaptations to extremely low specific growth, transcriptome changes were analysed. These revealed that cellular responses to near-zero growth conditions share several similarities with those of cells during the stationary phase of batch growth. However, fundamental differences between these two non-growing states are apparent by their high viability and absence of stationary phase mutagenesis under near-zero growth conditions. PMID:25367190

  14. Effect of walking stress on growth, physiological adaptability and endocrine responses in Malpura ewes in a semi-arid tropical environment

    NASA Astrophysics Data System (ADS)

    Sejian, Veerasamy; Maurya, Vijai P.; Naqvi, Syed M. K.

    2012-03-01

    Sheep in hot semi-arid environments are mostly reared using extensive systems. In addition to thermal stress and feed scarcity, the animals need to walk long distances for grazing in this ecological zone. A study was conducted to assess the effect of long-distance walking on adaptive capability in terms of physiological, biochemical and endocrine responses in Malpura ewes. Fourteen adult Malpura non-pregnant ewes weighing between 33 and 35 kg were used in the study. The ewes were randomly allocated into two groups of seven animals each: GI ( n = 7; Control), and GII ( n = 7; walking stress). The animals were stall-fed with a diet consisting of 70% roughage and 30% concentrate. Both GI and GII ewes had uniform access to feed and water. The walking stress group (GII) ewes were made to walk 14 km in two spans between 0900 and 1500 hours with 1 h 30 min for each span (7 km) of walking. The ewes subjected to walking stress (GII) were prevented from grazing by applying a face mask made of cotton thread. The study was conducted for a period of two estrous cycles (35 days) during the autumn season (October-November). Physiological responses were recorded twice daily at 0800 and 1400 hours at weekly intervals. Blood samples were collected from the jugular vein at weekly intervals to study the effects of walking stress on blood biochemical and endocrine parameters. The results indicate that walking stress had significant ( P < 0.05) influence on body weight, average daily gain, respiration rate (RR), rectal temperature (RT), haemoglobin (Hb), packed cell volume (PCV), plasma glucose, calcium, phosphorus, aspartate amino transferase (AST), alanine amino transferase (ALT), tri-iodo-thyronine (T3), thyroxin (T4), and cortisol. However, walking stress did not influence the reproductive hormone levels. The significant changes in RR, RT, plasma cortisol, T3 and T4 show that Malpura ewes have the capability to adapt to long-distance walking, and that adrenal and thyroid gland hormones play a significant role in such adaptation.

  15. Do telomeres adapt to physiological stress? Exploring the effect of exercise on telomere length and telomere-related proteins.

    PubMed

    Ludlow, Andrew T; Ludlow, Lindsay W; Roth, Stephen M

    2013-01-01

    Aging is associated with a tissue degeneration phenotype marked by a loss of tissue regenerative capacity. Regenerative capacity is dictated by environmental and genetic factors that govern the balance between damage and repair. The age-associated changes in the ability of tissues to replace lost or damaged cells is partly the cause of many age-related diseases such as Alzheimer's disease, cardiovascular disease, type II diabetes, and sarcopenia. A well-established marker of the aging process is the length of the protective cap at the ends of chromosomes, called telomeres. Telomeres shorten with each cell division and with increasing chronological age and short telomeres have been associated with a range of age-related diseases. Several studies have shown that chronic exposure to exercise (i.e., exercise training) is associated with telomere length maintenance; however, recent evidence points out several controversial issues concerning tissue-specific telomere length responses. The goals of the review are to familiarize the reader with the current telomere dogma, review the literature exploring the interactions of exercise with telomere phenotypes, discuss the mechanistic research relating telomere dynamics to exercise stimuli, and finally propose future directions for work related to telomeres and physiological stress. PMID:24455708

  16. Whole transcriptome analysis of the fasting and fed Burmese python heart: insights into extreme physiological cardiac adaptation.

    PubMed

    Wall, Christopher E; Cozza, Steven; Riquelme, Cecilia A; McCombie, W Richard; Heimiller, Joseph K; Marr, Thomas G; Leinwand, Leslie A

    2011-01-01

    The infrequently feeding Burmese python (Python molurus) experiences significant and rapid postprandial cardiac hypertrophy followed by regression as digestion is completed. To begin to explore the molecular mechanisms of this response, we have sequenced and assembled the fasted and postfed Burmese python heart transcriptomes with Illumina technology using the chicken (Gallus gallus) genome as a reference. In addition, we have used RNA-seq analysis to identify differences in the expression of biological processes and signaling pathways between fasted, 1 day postfed (DPF), and 3 DPF hearts. Out of a combined transcriptome of ?2,800 mRNAs, 464 genes were differentially expressed. Genes showing differential expression at 1 DPF compared with fasted were enriched for biological processes involved in metabolism and energetics, while genes showing differential expression at 3 DPF compared with fasted were enriched for processes involved in biogenesis, structural remodeling, and organization. Moreover, we present evidence for the activation of physiological and not pathological signaling pathways in this rapid, novel model of cardiac growth in pythons. Together, our data provide the first comprehensive gene expression profile for a reptile heart. PMID:21045117

  17. Gut physiology mediates a trade-off between adaptation to malnutrition and susceptibility to food-borne pathogens.

    PubMed

    Vijendravarma, Roshan K; Narasimha, Sunitha; Chakrabarti, Sveta; Babin, Aurelie; Kolly, Sylvain; Lemaitre, Bruno; Kawecki, Tadeusz J

    2015-10-01

    The animal gut plays a central role in tackling two common ecological challenges, nutrient shortage and food-borne parasites, the former by efficient digestion and nutrient absorption, the latter by acting as an immune organ and a barrier. It remains unknown whether these functions can be independently optimised by evolution, or whether they interfere with each other. We report that Drosophila melanogaster populations adapted during 160 generations of experimental evolution to chronic larval malnutrition became more susceptible to intestinal infection with the opportunistic bacterial pathogen Pseudomonas entomophila. However, they do not show suppressed immune response or higher bacterial loads. Rather, their increased susceptibility to P. entomophila is largely mediated by an elevated predisposition to loss of intestinal barrier integrity upon infection. These results may reflect a trade-off between the efficiency of nutrient extraction from poor food and the protective function of the gut, in particular its tolerance to pathogen-induced damage. PMID:26249109

  18. Larval exposure to 4-nonylphenol and 17?-estradiol affects physiological and behavioral development of seawater adaptation in Atlantic salmon smolts

    USGS Publications Warehouse

    Lerner, Darrren T.; Bjornsson, Bjorn Thrandur; McCormick, Stephen D.

    2007-01-01

    Population declines of anadromous salmonids are attributed to anthropogenic disturbances including dams, commercial and recreational fisheries, and pollutants, such as estrogenic compounds. Nonylphenol (NP), a xenoestrogen, is widespread in the aquatic environment due to its use in agricultural, industrial, and household products. We exposed Atlantic salmon yolk-sac larvae to waterborne 10 or 100 ?g L-1 NP (NP-L or NP-H, respectively), 2 ?g L-1 17?-estradiol (E2), or vehicle, for 21 days to investigate their effects on smolt physiology and behavior 1 year later. NP-H caused approximately 50% mortality during exposure, 30 days after exposure, and 60 days after exposure. Mortality rates of NP-L and E2 fish were not affected until 60 days after treatment, when they were 4-fold greater than those of controls. Treatment with NP-L or E2 as yolk-sac larvae decreased gill sodium-potassium-activated adenosine triphosphatase (Na+,K+-ATPase) activity and seawater (SW) tolerance during smolt development, 1 year after exposure. Exposure to NP-L and E2 resulted in a latency to enter SW and reduced preference for SW approximately 2- and 5-fold, respectively. NP-L-exposed fish had 20% lower plasma insulin-like growth factor I (IGF-I) levels and 35% lower plasma triiodothyronine (T3). Plasma growth hormone and thyroxine (T4) were unaffected. Exposure to E2 did not affect plasma levels of IGF-I, GH, T3, or T4. Both treatment groups exhibited increased plasma cortisol and decreased osmoregulatory capacity in response to a handling stressor. These results suggest that early exposure to environmentally relevant concentrations of NP, and other estrogenic compounds, can cause direct and delayed mortalities and that this exposure can have long term, “organizational” effects on life-history events in salmonids.

  19. Using physiologically based pharmacokinetic modeling to address nonlinear kinetics and changes in rodent physiology and metabolism due to aging and adaptation in deriving reference values for propylene glycol methyl ether and propylene glycol methyl ether acetate.

    SciTech Connect

    Kirman, C R.; Sweeney, Lisa M.; Corley, Rick A.; Gargas, M L.

    2005-04-01

    Reference values, including an oral reference dose (RfD) and an inhalation reference concentration (RfC), were derived for propylene glycol methyl ether (PGME), and an oral RfD was derived for its acetate (PGMEA). These values were based upon transient sedation observed in F344 rats and B6C3F1 mice during a two-year inhalation study. The dose-response relationship for sedation was characterized using internal dose measures as predicted by a physiologically based pharmacokinetic (PBPK) model for PGME and its acetate. PBPK modeling was used to account for changes in rodent physiology and metabolism due to aging and adaptation, based on data collected during weeks 1, 2, 26, 52, and 78 of a chronic inhalation study. The peak concentration of PGME in richly perfused tissues was selected as the most appropriate internal dose measure based upon a consideration of the mode of action for sedation and similarities in tissue partitioning between brain and other richly perfused tissues. Internal doses (peak tissue concentrations of PGME) were designated as either no-observed-adverse-effect levels (NOAELs) or lowest-observed-adverse-effect levels (LOAELs) based upon the presence or absence of sedation at each time-point, species, and sex in the two year study. Distributions of the NOAEL and LOAEL values expressed in terms of internal dose were characterized using an arithmetic mean and standard deviation, with the mean internal NOAEL serving as the basis for the reference values, which was then divided by appropriate uncertainty factors. Where data were permitting, chemical-specific adjustment factors were derived to replace default uncertainty factor values of ten. Nonlinear kinetics are were predicted by the model in all species at PGME concentrations exceeding 100 ppm, which complicates interspecies and low-dose extrapolations. To address this complication, reference values were derived using two approaches which differ with respect to the order in which these extrapolations were performed: (1) uncertainty factor application followed by interspecies extrapolation (PBPK modeling); and (2) interspecies extrapolation followed by uncertainty factor application. The resulting reference values for these two approaches are substantially different, with values from the former approach being 7-fold higher than those from the latter approach. Such a striking difference between the two approaches reveals an underlying issue that has received little attention in the literature regarding the application of uncertainty factors and interspecies extrapolations to compounds where saturable kinetics occur in the range of the NOAEL. Until such discussions have taken place, reference values based on the latter approach are recommended for risk assessments involving human exposures to PGME and PGMEA.

  20. The Effects of Sprint Interval vs. Continuous Endurance Training on Physiological And Metabolic Adaptations in Young Healthy Adults

    PubMed Central

    Nalcakan, Gulbin Rudarli

    2014-01-01

    The purpose of this study was to compare the effects of sprint interval training (SIT) and continuous endurance training (CET) on selected anthropometric, aerobic, and anaerobic performance indices as well as the blood lipid profile, inflammatory and muscle damage markers in healthy young males. Fifteen recreationally active male volunteers (age: 21.7 ±2.2 years, body mass: 83.0 ±8.0 kg, body height: 1.82 ±0.05 m) were divided into two groups according to their initial VO2max levels. Training programs were conducted 3 times per week for 7 weeks. The SIT program consisted of 4–6 Wingate anaerobic sprints with a 4.5 min recovery, while CET consisted of 30–50 min cycling at 60% VO2max. Biochemical, anthropometric and fitness assessments were performed both pre and post-intervention. Significant improvements in VO2max, anaerobic power and capacity, and VO2 utilization during the submaximal workout and significant decreases in body fat and in waist circumference after the intervention occurred in both SIT and CET groups. Significantly greater gross efficiency was measured in the CET group. No differences in the lipid profile or serum levels of inflammatory, myocardial and skeletal muscle damage markers were observed after the training period. The study results agree with the effectiveness of a 30 s all-out training program with a reduced time commitment for anthropometric, aerobic and anaerobic adaptation and eliminate doubts about its safety as a model. PMID:25713670

  1. Genome-Guided Analysis of Physiological Capacities of Tepidanaerobacter acetatoxydans Provides Insights into Environmental Adaptations and Syntrophic Acetate Oxidation

    PubMed Central

    Niazi, Adnan; Bongcam-Rudloff, Erik; Schnürer, Anna

    2015-01-01

    This paper describes the genome-based analysis of Tepidanaerobacter acetatoxydans strain Re1, a syntrophic acetate-oxidising bacterium (SAOB). Principal issues such as environmental adaptations, metabolic capacities, and energy conserving systems have been investigated and the potential consequences for syntrophic acetate oxidation discussed. Briefly, in pure culture, T. acetatoxydans grows with different organic compounds and produces acetate as the main product. In a syntrophic consortium with a hydrogenotrophic methanogen, it can also reverse its metabolism and instead convert acetate to formate/H2 and CO2. It can only proceed if the product formed is continuously removed. This process generates a very small amount of energy that is scarcely enough for growth, which makes this particular syntrophy of special interest. As a crucial member of the biogas-producing community in ammonium-rich engineered AD processes, genomic features conferring ammonium resistance, bacterial defense, oxygen and temperature tolerance were found, as well as attributes related to biofilm formation and flocculation. It is likely that T. acetatoxydans can form an electrochemical gradient by putative electron-bifurcating Rnf complex and [Fe-Fe] hydrogenases, as observed in other acetogens. However, genomic deficiencies related to acetogenic metabolism and anaerobic respiration were discovered, such as the lack of formate dehydrogenase and F1F0 ATP synthase. This has potential consequences for the metabolic pathways used under SAO and non-SAO conditions. The two complete sets of bacteriophage genomes, which were found to be encoded in the genome, are also worthy of mention. PMID:25811859

  2. Different Blood Cell-Derived Transcriptome Signatures in Cows Exposed to Vaccination Pre- or Postpartum

    PubMed Central

    Weikard, Rosemarie; Demasius, Wiebke; Hadlich, Frieder; Kühn, Christa

    2015-01-01

    Periparturient cows have been found to reveal immunosuppression, frequently associated with increased susceptibility to uterine and mammary infections. To improve understanding of the causes and molecular regulatory mechanisms accounting for this phenomenon around calving, we examined the effect of an antigen challenge on gene expression modulation on cows prior to (BC) or after calving (AC) using whole transcriptome sequencing (RNAseq). The transcriptome analysis of the cows’ blood identified a substantially higher number of loci affected in BC cows (2,235) in response to vaccination compared to AC cows (208) and revealed a divergent transcriptional profile specific for each group. In BC cows, a variety of loci involved in immune defense and cellular signaling processes were transcriptionally activated, whereas protein biosynthesis and posttranslational processes were tremendously impaired in response to vaccination. Furthermore, energy metabolism in the blood cells of BC cows was shifted from oxidative phosphorylation to the glycolytic system. In AC cows, the number and variety of regulated pathways involved in immunomodulation and maintenance of immnunocompetence are considerably lower after vaccination, and upregulation of arginine degradation was suggested as an immunosuppressive mechanism. Elevated transcript levels of erythrocyte-specific genes involved in gas exchange processes were a specific transcriptional signature in AC cows pointing to hematopoiesis activation. The divergent and substantially lower magnitude of transcriptional modulation in response to vaccination in AC cows provides evidence for a suppressed immune capacity of early lactating cows on the molecular level and demonstrates that an efficient immune response of cows is related to their physiological and metabolic status. PMID:26317664

  3. Physiological and behavioral basis for the successful adaptation of goats to severe water restriction under hot environmental conditions.

    PubMed

    Kaliber, M; Koluman, N; Silanikove, N

    2016-01-01

    Among domestic ruminants, goats are renowned for their ability to tolerate water deprivation, water restriction and energy restriction. However, some basic questions regarding their ability to endure water restriction under heat stress are still open. Three levels of water restriction (56%, 73% and 87% of the ad libitum) were imposed on 20 cross-bred 3-year-old female goats (75% German Fawn and 25% Hair Goat) distributed into four groups, with five animals per treatment. The experiment was conducted from the beginning of July to the end of August in a farm located in the Eastern Mediterranean region of Turkey (40 m in altitude; 36 59' N, 35 18'E), in which subtropical weather conditions prevail. The average daily temperature during the experiment was 34.2°C, whereas the highest and lowest temperatures were 42°C and 23.1°C, respectively. The average relative humidity was 68.2% and wind speed was 1.2 km/h. Weekly average thermal heat indexes during the experiment were 78.3 (week 1), 79.1 (week 2), 80.1 (weak 3), 79.8 (weak 4), 81.3 (weak 5) and on average 79.7. Feed intake, heart rate, thermoregulatory responses (rectal temperature, respiration rate), blood plasma concentrations of ions (Na, K), antidiuretic hormone (ADH), metabolites (glucose, cholesterol, creatinine and urea) and behavioral aspects (standing, walking, lying) were studied over 30 days. The responses to water restriction were proportional to the level of restriction. The reductions in feed intake (up to 13%), BW (up to 4.6%) and the increases in rectal temperature (0.5°C) and breath rate (10 respirations/min) were moderate and also were far from responses encountered under severe heat and water stresses. The increase in plasma Na (from 119 to 140 mM) and ADH concentrations (from 12.6 to 17.4 pg/ml) indicates that the physiological response to water restriction was in response to mild dehydration, which also explains the increase in blood plasma concentrations of glucose, cholesterol, creatinine and urea. Behavioral responses (reduction in walking from 226 to 209 min/day and increase in lying from 417 to 457 min/day) were associated with conservation of energy or thermoregulation (reducing the exposure to direct radiation). PMID:26256149

  4. BEEF COW EFFICIENCY - REVISITED

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Variation exists among cattle populations to improve the conversion of feed resources to a final product. A biologically efficient cow is one producing a calf each year she remains in the cowherd. The nutrition-reproduction axis may influence this success. Energy expenditure for maintenance may af...

  5. Genus-Wide Comparative Genomics of Malassezia Delineates Its Phylogeny, Physiology, and Niche Adaptation on Human Skin

    PubMed Central

    Wu, Guangxi; Zhao, He; Li, Chenhao; Rajapakse, Menaka Priyadarsani; Wong, Wing Cheong; Xu, Jun; Saunders, Charles W.; Reeder, Nancy L.; Reilman, Raymond A.; Scheynius, Annika; Sun, Sheng; Billmyre, Blake Robert; Li, Wenjun; Averette, Anna Floyd; Mieczkowski, Piotr; Heitman, Joseph; Theelen, Bart; Schröder, Markus S.; De Sessions, Paola Florez; Butler, Geraldine; Maurer-Stroh, Sebastian; Boekhout, Teun; Nagarajan, Niranjan; Dawson, Thomas L.

    2015-01-01

    Malassezia is a unique lipophilic genus in class Malasseziomycetes in Ustilaginomycotina, (Basidiomycota, fungi) that otherwise consists almost exclusively of plant pathogens. Malassezia are typically isolated from warm-blooded animals, are dominant members of the human skin mycobiome and are associated with common skin disorders. To characterize the genetic basis of the unique phenotypes of Malassezia spp., we sequenced the genomes of all 14 accepted species and used comparative genomics against a broad panel of fungal genomes to comprehensively identify distinct features that define the Malassezia gene repertoire: gene gain and loss; selection signatures; and lineage-specific gene family expansions. Our analysis revealed key gene gain events (64) with a single gene conserved across all Malassezia but absent in all other sequenced Basidiomycota. These likely horizontally transferred genes provide intriguing gain-of-function events and prime candidates to explain the emergence of Malassezia. A larger set of genes (741) were lost, with enrichment for glycosyl hydrolases and carbohydrate metabolism, concordant with adaptation to skin’s carbohydrate-deficient environment. Gene family analysis revealed extensive turnover and underlined the importance of secretory lipases, phospholipases, aspartyl proteases, and other peptidases. Combining genomic analysis with a re-evaluation of culture characteristics, we establish the likely lipid-dependence of all Malassezia. Our phylogenetic analysis sheds new light on the relationship between Malassezia and other members of Ustilaginomycotina, as well as phylogenetic lineages within the genus. Overall, our study provides a unique genomic resource for understanding Malassezia niche-specificity and potential virulence, as well as their abundance and distribution in the environment and on human skin. PMID:26539826

  6. Genus-Wide Comparative Genomics of Malassezia Delineates Its Phylogeny, Physiology, and Niche Adaptation on Human Skin.

    PubMed

    Wu, Guangxi; Zhao, He; Li, Chenhao; Rajapakse, Menaka Priyadarsani; Wong, Wing Cheong; Xu, Jun; Saunders, Charles W; Reeder, Nancy L; Reilman, Raymond A; Scheynius, Annika; Sun, Sheng; Billmyre, Blake Robert; Li, Wenjun; Averette, Anna Floyd; Mieczkowski, Piotr; Heitman, Joseph; Theelen, Bart; Schröder, Markus S; De Sessions, Paola Florez; Butler, Geraldine; Maurer-Stroh, Sebastian; Boekhout, Teun; Nagarajan, Niranjan; Dawson, Thomas L

    2015-11-01

    Malassezia is a unique lipophilic genus in class Malasseziomycetes in Ustilaginomycotina, (Basidiomycota, fungi) that otherwise consists almost exclusively of plant pathogens. Malassezia are typically isolated from warm-blooded animals, are dominant members of the human skin mycobiome and are associated with common skin disorders. To characterize the genetic basis of the unique phenotypes of Malassezia spp., we sequenced the genomes of all 14 accepted species and used comparative genomics against a broad panel of fungal genomes to comprehensively identify distinct features that define the Malassezia gene repertoire: gene gain and loss; selection signatures; and lineage-specific gene family expansions. Our analysis revealed key gene gain events (64) with a single gene conserved across all Malassezia but absent in all other sequenced Basidiomycota. These likely horizontally transferred genes provide intriguing gain-of-function events and prime candidates to explain the emergence of Malassezia. A larger set of genes (741) were lost, with enrichment for glycosyl hydrolases and carbohydrate metabolism, concordant with adaptation to skin's carbohydrate-deficient environment. Gene family analysis revealed extensive turnover and underlined the importance of secretory lipases, phospholipases, aspartyl proteases, and other peptidases. Combining genomic analysis with a re-evaluation of culture characteristics, we establish the likely lipid-dependence of all Malassezia. Our phylogenetic analysis sheds new light on the relationship between Malassezia and other members of Ustilaginomycotina, as well as phylogenetic lineages within the genus. Overall, our study provides a unique genomic resource for understanding Malassezia niche-specificity and potential virulence, as well as their abundance and distribution in the environment and on human skin. PMID:26539826

  7. Lack of Physiological Depth Patterns in Conspecifics of Endemic Antarctic Brown Algae: A Trade-Off between UV Stress Tolerance and Shade Adaptation?

    PubMed

    Gómez, Iván; Huovinen, Pirjo

    2015-01-01

    A striking characteristic of endemic Antarctic brown algae is their broad vertical distribution. This feature is largely determined by the shade adaptation in order to cope with the seasonal variation in light availability. However, during spring-summer months, when light penetrates deep in the water column these organisms have to withstand high levels of solar radiation, including UV. In the present study we examine the light use characteristics in parallel to a potential for UV tolerance (measured as content of phenolic compounds, antioxidant activity and maximum quantum yield of fluorescence) in conspecific populations of four Antarctic brown algae (Ascoseira mirabilis, Desmarestia menziesii, D. anceps and Himantothallus grandifolius) distributed over a depth gradient between 5 and 30 m. The main results indicated that a) photosynthetic efficiency was uniform along the depth gradient in all the studied species, and b) short-term (6 h) exposure to UV radiation revealed a high tolerance measured as chlorophyll fluorescence, phlorotannin content and antioxidant capacity. Multivariate analysis of similarity indicated that light requirements for photosynthesis, soluble phlorotannins and antioxidant capacity are the variables determining the responses along the depth gradient in all the studied species. The suite of physiological responses of algae with a shallower distribution (A. mirabilis and D. menziesii) differed from those with deeper vertical range (D. anceps and H. grandifolius). These patterns are consistent with the underwater light penetration that defines two zones: 0-15 m, with influence of UV radiation (1% of UV-B and UV-A at 9 m and 15 m respectively) and a zone below 15 m marked by PAR incidence (1% up to 30 m). These results support the prediction that algae show a UV stress tolerance capacity along a broad depth range according to their marked shade adaptation. The high contents of phlorotannins and antioxidant potential appear to be strongly responsible for the lack of clear depth patterns in light demand characteristics and UV tolerance. PMID:26252953

  8. Lack of Physiological Depth Patterns in Conspecifics of Endemic Antarctic Brown Algae: A Trade-Off between UV Stress Tolerance and Shade Adaptation?

    PubMed Central

    Gómez, Iván; Huovinen, Pirjo

    2015-01-01

    A striking characteristic of endemic Antarctic brown algae is their broad vertical distribution. This feature is largely determined by the shade adaptation in order to cope with the seasonal variation in light availability. However, during spring-summer months, when light penetrates deep in the water column these organisms have to withstand high levels of solar radiation, including UV. In the present study we examine the light use characteristics in parallel to a potential for UV tolerance (measured as content of phenolic compounds, antioxidant activity and maximum quantum yield of fluorescence) in conspecific populations of four Antarctic brown algae (Ascoseira mirabilis, Desmarestia menziesii, D. anceps and Himantothallus grandifolius) distributed over a depth gradient between 5 and 30 m. The main results indicated that a) photosynthetic efficiency was uniform along the depth gradient in all the studied species, and b) short-term (6 h) exposure to UV radiation revealed a high tolerance measured as chlorophyll fluorescence, phlorotannin content and antioxidant capacity. Multivariate analysis of similarity indicated that light requirements for photosynthesis, soluble phlorotannins and antioxidant capacity are the variables determining the responses along the depth gradient in all the studied species. The suite of physiological responses of algae with a shallower distribution (A. mirabilis and D. menziesii) differed from those with deeper vertical range (D. anceps and H. grandifolius). These patterns are consistent with the underwater light penetration that defines two zones: 0–15 m, with influence of UV radiation (1% of UV-B and UV-A at 9 m and 15 m respectively) and a zone below 15 m marked by PAR incidence (1% up to 30 m). These results support the prediction that algae show a UV stress tolerance capacity along a broad depth range according to their marked shade adaptation. The high contents of phlorotannins and antioxidant potential appear to be strongly responsible for the lack of clear depth patterns in light demand characteristics and UV tolerance. PMID:26252953

  9. The relationship between evolutionary and physiological variation in hemoglobin

    E-print Network

    Kirschner, Marc W.

    , 2007) Physiological and evolutionary adaptations operate at very differ- ent time scales. Nevertheless between physiological and evolutionary adaptations. We compare measurements of ox- ygen saturation curves continued selection for physiological adaptability and hints at a role for this adaptability in evolutionary

  10. Disruption of hypothalamic leptin signaling in mice leads to early-onset obesity, but physiological adaptations in mature animals stabilize adiposity levels

    PubMed Central

    Ring, Laurence E.; Zeltser, Lori M.

    2010-01-01

    Distinct populations of leptin-sensing neurons in the hypothalamus, midbrain, and brainstem contribute to the regulation of energy homeostasis. To assess the requirement for leptin signaling in the hypothalamus, we crossed mice with a floxed leptin receptor allele (Leprfl) to mice transgenic for Nkx2.1-Cre, which drives Cre expression in the hypothalamus and not in more caudal brain regions, generating LeprNkx2.1KO mice. From weaning, LeprNkx2.1KO mice exhibited phenotypes similar to those observed in mice with global loss of leptin signaling (Leprdb/db mice), including increased weight gain and adiposity, hyperphagia, cold intolerance, and insulin resistance. However, after 8 weeks of age, LeprNkx2.1KO mice maintained stable adiposity levels, whereas the body fat percentage of Leprdb/db animals continued to escalate. The divergence in the adiposity phenotypes of Leprdb/db and LeprNkx2.1KO mice with age was concomitant with increased rates of linear growth and energy expenditure in LeprNkx2.1KO mice. These data suggest that remaining leptin signals in LeprNkx2.1KO mice mediate physiological adaptations that prevent the escalation of the adiposity phenotype in adult mice. The persistence of severe adiposity in LeprNkx2.1KO mice, however, suggests that compensatory actions of circuits regulating growth and energy expenditure are not sufficient to reverse obesity established at an early age. PMID:20592471

  11. Insights into the Physiology and Ecology of the Brackish-Water-Adapted Cyanobacterium Nodularia spumigena CCY9414 Based on a Genome-Transcriptome Analysis

    PubMed Central

    Voß, Björn; Bolhuis, Henk; Fewer, David P.; Kopf, Matthias; Möke, Fred; Haas, Fabian; El-Shehawy, Rehab; Hayes, Paul; Bergman, Birgitta; Sivonen, Kaarina; Dittmann, Elke; Scanlan, Dave J.; Hagemann, Martin; Stal, Lucas J.; Hess, Wolfgang R.

    2013-01-01

    Nodularia spumigena is a filamentous diazotrophic cyanobacterium that dominates the annual late summer cyanobacterial blooms in the Baltic Sea. But N. spumigena also is common in brackish water bodies worldwide, suggesting special adaptation allowing it to thrive at moderate salinities. A draft genome analysis of N. spumigena sp. CCY9414 yielded a single scaffold of 5,462,271 nucleotides in length on which genes for 5,294 proteins were annotated. A subsequent strand-specific transcriptome analysis identified more than 6,000 putative transcriptional start sites (TSS). Orphan TSSs located in intergenic regions led us to predict 764 non-coding RNAs, among them 70 copies of a possible retrotransposon and several potential RNA regulators, some of which are also present in other N2-fixing cyanobacteria. Approximately 4% of the total coding capacity is devoted to the production of secondary metabolites, among them the potent hepatotoxin nodularin, the linear spumigin and the cyclic nodulapeptin. The transcriptional complexity associated with genes involved in nitrogen fixation and heterocyst differentiation is considerably smaller compared to other Nostocales. In contrast, sophisticated systems exist for the uptake and assimilation of iron and phosphorus compounds, for the synthesis of compatible solutes, and for the formation of gas vesicles, required for the active control of buoyancy. Hence, the annotation and interpretation of this sequence provides a vast array of clues into the genomic underpinnings of the physiology of this cyanobacterium and indicates in particular a competitive edge of N. spumigena in nutrient-limited brackish water ecosystems. PMID:23555932

  12. Cow's milk protein allergy.

    PubMed

    Solinas, C; Corpino, M; Maccioni, R; Pelosi, U

    2010-10-01

    Cow's milk protein allergy (CMPA) affects 2-7.5% of children; persistence in adulthood is uncommon since a tolerance develops in 51% of cases within 2 years and 80% within 3-4 years. CMPA is an immunological reaction to one or more milk proteins: ?-lactalbumin, ß-lactoglobulin, casein, IgE or non-IgE associated, responsible of immediate or late onset symptoms. The suspicion of CMPA is based on detailed family and medical history, skin test, patch test, laboratory test, an elimination diet and food challenge. The general treatment for CMPA is dietary: elimination of cow's milk protein and introduction of extensively hydrolyzed whey or casein formula, amino acid formula, and soy formula. Extensively hydrolyzed whey or casein formula is recommended as first choice for infants in mild or moderate reactions, amino acid formula in severe CMPA and in cases with poor response to extensively hydrolysed whey or casein formula. PMID:20836734

  13. Differences in leukocyte profile, gene expression, and metabolite status of dairy cows with or without sole ulcers.

    PubMed

    O'Driscoll, Keelin; McCabe, Matthew; Earley, Bernadette

    2015-03-01

    Sole ulcers are one of the most severe pathologies causing lameness in dairy cows and are associated with abnormal behavior and impaired production performance. However, little is known about how or whether lameness caused by sole ulcers affects the cow systemically. This study compared hematology profile, leukocyte gene expression, and physiological responses [metabolite, cortisol, the endogenous steroid hormone dehydroepiandrosterone (DHEA), and haptoglobin concentrations] of cows with sole ulcers and healthy cows. Twelve clinically lame cows (lame) were identified as having at least one sole ulcer and no other disorder, and matched with a cow that had good locomotion and no disorders (sound), using days in milk, liveweight, body condition score, and diet. Blood samples were taken from all 24 cows within 24h of sole ulcer diagnosis. Leukocyte counts were obtained using an automated cell counter, cortisol and DHEA concentration by ELISA, and plasma haptoglobin, urea, total protein, creatine kinase, and glucose were analyzed on an Olympus analyzer. Expression of 16 genes associated with lameness or stress were estimated using reverse transcription-PCR. Data were analyzed using the MIXED procedure in SAS software (version 9.3; SAS Institute Inc., Cary, NC). Lame cows had a higher neutrophil percentage, a numerically lower lymphocyte percentage, and tended to have a higher neutrophil:lymphocyte ratio than sound cows. Serum cortisol and DHEA concentrations were higher in lame than in sound cows. Lame cows also tended to have higher haptoglobin and glucose levels than sound, as well as higher protein yet lower urea levels. Sound cows tended to have higher relative expression of the gene coding for colony-stimulating factor 2 than lame, but in all other cases where differences were detected in cytokine gene expression (IL-1?, IL-1?, CXCL8, and IL-10), relative gene expression in sound cows tended to be, or was, lower than in lame. Relative expression of MMP-13, GR-?, Fas, haptoglobin, and CD62L were, or tended to be, higher in lame than sound cows. A high neutrophil:lymphocyte ratio in combination with higher cortisol levels in cows with ulcers is indicative of physiological stress. Moreover, increased DHEA and a higher cortisol:DHEA ratio, as well as a tendency for higher haptoglobin levels and increased haptoglobin mRNA expression, are indicative of systemic inflammation. Increased cytokine mRNA expression indicates activation of the immune system compared with healthy cows. Increased expression of MMP-13 mRNA has been found in cows with impaired locomotion and thus could be implicated in development of claw horn disorders. PMID:25557893

  14. Physiological responses of emerald ash borer larvae to feeding on different ash species reveal putative resistance mechanisms and insect counter-adaptations.

    PubMed

    Rigsby, C M; Showalter, D N; Herms, D A; Koch, J L; Bonello, P; Cipollini, D

    2015-07-01

    Emerald ash borer, Agrilus planipennis Fairmaire, an Asian wood-boring beetle, has devastated ash (Fraxinus spp.) trees in North American forests and landscapes since its discovery there in 2002. In this study, we collected living larvae from EAB-resistant Manchurian ash (Fraxinus mandschurica), and susceptible white (Fraxinus americana) and green (Fraxinus pennsylvanica) ash hosts, and quantified the activity and production of selected detoxification, digestive, and antioxidant enzymes. We hypothesized that differences in larval physiology could be used to infer resistance mechanisms of ash. We found no differences in cytochrome P450, glutathione-S-transferase, carboxylesterase, sulfotransferase, and tryptic BApNAase activities between larvae feeding on different hosts. Despite this, Manchurian ash-fed larvae produced a single isozyme of low electrophoretic mobility that was not produced in white or green ash-fed larvae. Additionally, larvae feeding on white and green ash produced two serine protease isozymes of high electrophoretic mobility that were not observed in Manchurian ash-fed larvae. We also found lower activity of ?-glucosidase and higher activities of monoamine oxidase, ortho-quinone reductase, catalase, superoxide dismutase, and glutathione reductase in Manchurian ash-fed larvae compared to larvae that had fed on susceptible ash. A single isozyme was detected for both catalase and superoxide dismutase in all larval groups. The activities of the quinone-protective and antioxidant enzymes are consistent with the resistance phenotype of the host species, with the highest activities measured in larvae feeding on resistant Manchurian ash. We conclude that larvae feeding on Manchurian ash could be under quinone and oxidative stress, suggesting these may be potential mechanisms of resistance of Manchurian ash to EAB larvae, and that quinone-protective and antioxidant enzymes are important counter-adaptations of larvae for dealing with these resistance mechanisms. PMID:25956198

  15. Future consequences and challenges for dairy cow production systems arising from climate change in Central Europe - a review.

    PubMed

    Gauly, M; Bollwein, H; Breves, G; Brügemann, K; Dänicke, S; Da?, G; Demeler, J; Hansen, H; Isselstein, J; König, S; Lohölter, M; Martinsohn, M; Meyer, U; Potthoff, M; Sanker, C; Schröder, B; Wrage, N; Meibaum, B; von Samson-Himmelstjerna, G; Stinshoff, H; Wrenzycki, C

    2013-05-01

    It is well documented that global warming is unequivocal. Dairy production systems are considered as important sources of greenhouse gas emissions; however, little is known about the sensitivity and vulnerability of these production systems themselves to climate warming. This review brings different aspects of dairy cow production in Central Europe into focus, with a holistic approach to emphasize potential future consequences and challenges arising from climate change. With the current understanding of the effects of climate change, it is expected that yield of forage per hectare will be influenced positively, whereas quality will mainly depend on water availability and soil characteristics. Thus, the botanical composition of future grassland should include species that are able to withstand the changing conditions (e.g. lucerne and bird's foot trefoil). Changes in nutrient concentration of forage plants, elevated heat loads and altered feeding patterns of animals may influence rumen physiology. Several promising nutritional strategies are available to lower potential negative impacts of climate change on dairy cow nutrition and performance. Adjustment of feeding and drinking regimes, diet composition and additive supplementation can contribute to the maintenance of adequate dairy cow nutrition and performance. Provision of adequate shade and cooling will reduce the direct effects of heat stress. As estimated genetic parameters are promising, heat stress tolerance as a functional trait may be included into breeding programmes. Indirect effects of global warming on the health and welfare of animals seem to be more complicated and thus are less predictable. As the epidemiology of certain gastrointestinal nematodes and liver fluke is favourably influenced by increased temperature and humidity, relations between climate change and disease dynamics should be followed closely. Under current conditions, climate change associated economic impacts are estimated to be neutral if some form of adaptation is integrated. Therefore, it is essential to establish and adopt mitigation strategies covering available tools from management, nutrition, health and plant and animal breeding to cope with the future consequences of climate change on dairy farming. PMID:23253935

  16. Milk production responses to different strategies for feeding supplements to grazing dairy cows.

    PubMed

    Auldist, M J; Marett, L C; Greenwood, J S; Wright, M M; Hannah, M; Jacobs, J L; Wales, W J

    2016-01-01

    Milk production responses of grazing cows offered supplements in different ways were measured. Holstein-Friesian cows, averaging 45d in milk, were allocated into 8 groups of 24, with 2 groups randomly assigned to each of 4 feeding strategies. These were control: cows grazed a restricted allowance of perennial ryegrass pasture supplemented with milled wheat grain fed in the milking parlor and alfalfa hay offered in the paddock; FGM: same pasture and allowance as the control supplemented with a formulated grain mix containing wheat grain, corn grain, and canola meal fed in the parlor and alfalfa hay fed in the paddock; PMRL: same pasture and allowance as the control, supplemented with a PMR consisting of the same FGM but mixed with alfalfa hay and presented on a feed pad after each milking; and PMRH: same PMR fed in the same way as PMRL but with a higher pasture allowance. For all strategies, supplements provided the same metabolizable energy and grain:forage ratio [75:25, dry matter (DM) basis]. Each group of 24 cows was further allocated into 4 groups of 6, which were randomly assigned to receive 8, 12, 14, or 16kg of DM supplement/cow per d. Thus, 2 replicated groups per supplement amount per dietary strategy were used. The experiment had a 14-d adaptation period and a 14-d measurement period. Pasture allowance, measured to ground level, was approximately 14kg of DM/d for control, FGM, and PMRL cows, and 28kg of DM/d for the PMRH cows, and was offered in addition to the supplement. Positive linear responses to increasing amounts of supplement were observed for yield of milk, energy-corrected milk, fat, and protein for cows on all 4 supplement feeding strategies. Production of energy-corrected milk was greatest for PMRH cows, intermediate for FGM and PMRL cows, and lowest for control cows. Some of these differences in milk production related to differences in intake of pasture and supplement. Milk fat concentration decreased with increasing amount of supplement for all feeding strategies, but the decline was most marked for the control cows. Milk protein concentration increased for all groups as the amount of supplement increased, but was greater for FGM, PMRL, and PMRH cows than control cows. It is concluded that when supplements are fed to grazing dairy cows, inclusion of corn grain and canola meal can increase milk production even at similar metabolizable energy intakes, and that it does not matter whether these supplements are fed as a PMR or in the parlor and paddock. PMID:26585473

  17. Kinematic gait analysis and lactation performance in dairy cows fed a diet supplemented with zinc, manganese, copper and cobalt.

    PubMed

    Yamamoto, Satoshi; Ito, Kazuhiko; Suzuki, Kii; Matsushima, Yuki; Watanabe, Izumi; Watanabe, Yutaka; Abiko, Keima; Kamada, Toshihiko; Sato, Kan

    2014-03-01

    This study investigated how supplementation of the diet of dairy cows with trace minerals (zinc, manganese, copper and cobalt) affected kinematic gait parameters and lactation performance. Eight Holstein cows were divided into two groups, with each group receiving a different dietary treatment (control diet, or control diet supplemented with trace minerals) in a two-period crossover design. Kinematic gait parameters were calculated by using image analysis software. Compared to cows fed the control diet, cows that received the trace mineral-supplemented diet exhibited significantly increased walking and stepping rates, and had a shorter stance duration. Feed intake and milk production increased in cows fed the trace mineral-supplemented diet compared with control groups. The plasma manganese concentration was not different in control and experimental cows. In contrast, cobalt was only detected in the plasma of cows fed the supplemented diet. These results provide the first evidence that trace mineral supplementation of the diet of dairy cows affects locomotion, and that the associated gait changes can be detected by using kinematic gait analysis. Moreover, trace mineral supplementation improved milk production and only minimally altered blood and physiological parameters in dairy cows. PMID:24206275

  18. Procedures of Exercise Physiology Laboratories

    NASA Technical Reports Server (NTRS)

    Bishop, Phillip A.; Fortney, Suzanne; Greenisen, Michael; Siconolfi, Steven F.; Bamman, Marcas M.; Moore, Alan D., Jr.; Squires, William

    1998-01-01

    This manual describes the laboratory methods used to collect flight crew physiological performance data at the Johnson Space Center. The Exercise Countermeasures Project Laboratory is a standard physiology laboratory; only the application to the study of human physiological adaptations to spaceflight is unique. In the absence of any other recently published laboratory manual, this manual should be a useful document staffs and students of other laboratories.

  19. The Development of Real-Time Physiological Monitoring and Training Software for Remote Applications

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Autogenic Feedback Training Exercise (AFTE) is an protocol and technology developed by Dr. Patricia Cowings and her associates at NASA Ames Research Center as a means to facilitate astronaut adaptation to space and exposure to the microgravity. AFTE is a training method which involves teaching subjects to voluntarily control several of their own physiological responses to environmental stressors. As the procedures matured, the training program was expanded to determine if technology developed to facilitate astronaut adaptation to space would be valuable in treating patients suffering from autonomic and vestibular pathologies and symptomatic relief from nausea and/or blood pressure control anomalies such as hypo- or hypertension. The present study, performed in conjunction with Morehouse School of Medicine, Biomedical Engineering at The University of Akron and NASA Ames Research Center has demonstrated that this technology can be successfully applied over vast distances. The specific purpose of this research was to develop a PC based system which could handle processing of twenty channels of acquired physiological data in addition to the necessary duplex communication protocols that would, for example, permit a patient in Atlanta, GA to be trained by a clinician stationed in San Jose, CA. Sixteen channels of physiological data and 20 channels of processed data are included.

  20. Cow’s milk allergy: From allergens to new forms of diagnosis, therapy and prevention?

    PubMed Central

    Hochwallner, Heidrun; Schulmeister, Ulrike; Swoboda, Ines; Spitzauer, Susanne; Valenta, Rudolf

    2014-01-01

    The first adverse reactions to cow’s milk were already described 2000 years ago. However, it was only 50 years ago that several groups started with the analysis of cow’s milk allergens. Meanwhile the spectrum of allergy eliciting proteins within cow’s milk is identified and several cow’s milk allergens have been characterized regarding their biochemical properties, fold and IgE binding epitopes. The diagnosis of cow’s milk allergy is diverse ranging from fast and cheap in vitro assays to elaborate in vivo assays. Considerable effort was spent to improve the diagnosis from an extract-based into a component resolved concept. There is still no suitable therapy available against cow’s milk allergy except avoidance. Therefore research needs to focus on the development of suitable and safe immunotherapies that do not elicit severe side effect. PMID:23954566

  1. Effect of ambient temperature and sodium bicarbonate supplementation on water and electrolyte balances in dry and lactating Holstein cows.

    PubMed

    Khelil-Arfa, H; Faverdin, P; Boudon, A

    2014-04-01

    The aim of this study was to quantify the effect of the interaction between 2 constant ambient temperatures [thermoneutrality (TN; 15°C) and high temperature (HT; 28°C)] and 2 levels of Na bicarbonate supplementation [calculated to provide diet Na contents of 0.20%DM (Na-) and 0.50%DM (Na+)] on water partitioning in dairy cows. Treatments were compared on 4 dry and 4mid-lactation Holstein cows according to 2 Latin squares (1 for each physiological stage) over the course of 4 periods of 15d. Diets consisted of a total mixed ration based on maize silage. Dry cows were restricted to their protein and energy requirements, whereas lactating cows were fed ad libitum. The daily average temperature-humidity index was 59.4 for TN and 73.2 for HT. Lactating and dry cows had higher vaginal temperatures at HT than at TN, but the increase was more pronounced in lactating cows (+1.05 vs. +0.12°C for vaginal temperature, respectively). Dry matter intake (DMI) of lactating cows decreased by 2.3kg/d at HT. Free water intake (FWI) and estimated volume of water lost to evaporation increased at HT in both lactating and dry cows; no interactions were observed between temperature and physiological stage. When expressed as a proportion of DMI, the increase in evaporation that occurred with increasing temperature was completely compensated for by an increase in FWI for both physiological stages. The urinary water excretion increased slightly at HT in lactating cows but not in dry cows, which may be related to the low chloride content of the offered diet. High Na supplementation increased DMI slightly in lactating cows, but milk yield was not affected. Sodium supplementation did not limit the decrease in DMI observed in lactating cows at HT; this observation is likely due to the high diet electrolyte balance of the offered diets. Sodium supplementation increased FWI in lactating cows and urinary flow in both physiological states. The interaction between ambient temperature and Na supplementation did not affect either water intake or water evaporation. This study demonstrates that the development of predictive models for water intake that include environmental variables could be based on mechanistic models of evaporation. PMID:24485695

  2. Elevated non-esterified fatty acids and ?-hydroxybutyrate and their association with transition dairy cow performance.

    PubMed

    McArt, Jessica A A; Nydam, Daryl V; Oetzel, Garrett R; Overton, Thomas R; Ospina, Paula A

    2013-12-01

    Dairy cows pass through a period of negative energy balance as they transition from late gestation to early lactation. Poor adaptation through this period, expressed as excessively elevated concentrations of non-esterified fatty acids (NEFAs) pre- or post-partum and elevated concentrations of ?-hydroxybutyrate post-partum, increases an individual animal's risk of post-partum disease, removal from the herd, reproductive difficulty, and reduced milk production. Field studies have shown that subclinical ketosis often affects 40% of cows in a herd although the incidence can be as high as 80%. Peak incidence occurs at 5 days in milk, and cows that develop subclinical ketosis in the first week of lactation have a higher risk of negative effects and reduced milk production than cows that develop subclinical ketosis in the second week of lactation. Herds with more than a 15-20% prevalence of excessively elevated concentrations of NEFAs and ?-hydroxybutyrate in early lactation have higher rates of negative subsequent events, poorer reproduction, and lower milk yield than herds with a lower prevalence of negative energy balance. This paper reviews (1) strategies for testing of energy-related metabolites, (2) consequences of poor adaptation to negative energy balance (for individual animals and for herds), (3) treatment approaches for affected cows, and (4) economic considerations for testing and treating cows with poor adaptation to negative energy balance. PMID:24054909

  3. Your Cow and Calf Business. 

    E-print Network

    Maddox, L. A. Jr.; Thompson, Uel D.; Prater, Tom

    1960-01-01

    condition when the calves are dropped. 2. Sufficient feed and forage during the nursing period for the cows to supply adequate amounts , of milk. 3. Good milk production bred into the cow herd. 4. Calves with the genetic ability to grow rapidly. 5..., feeding and health problems. Average or Low Average or below weaning weights of calves may be due to one or more of the fol- lowing : 1. Cows may be too poor when calves are dropped to supply enough milk. 2. Total feed during part or all...

  4. Feeding Milk Cows. - Four Feeding Experiments With Milk Cows

    E-print Network

    Connell, J. H.; Clayton, Jas. (James)

    1894-01-01

    ATIOI! 3ULLETIN No. 33. DECEMRElt, 1894. TEEDING MILK COWS. JULTURAL AND MECHANICAL COLLEGE OF TEXAt POSTOFFICE : COLLEGE STATION, BRAZOR CO., TEXAS. Reports from this Rtstion are sent free to farmers of the State on application to J. H. CONNELL...-STATION SUPERINTENDENTS. ...................................... J. H. FERGUSON. McKinney. Collin Co. ........................................... 8. A. MCHENRY Beeville, Bee Co. ' TEXAS AGRICULTURAL EXPERIMENT STATION. Four Feeding Experiments with Milk Cows...

  5. Effects of feeding various dosages of Saccharomyces cerevisiae fermentation product in transition dairy cows.

    PubMed

    Zaworski, E M; Shriver-Munsch, C M; Fadden, N A; Sanchez, W K; Yoon, I; Bobe, G

    2014-05-01

    Feeding 56 versus 0 g/d of Saccharomyces cerevisiae fermentation product (SCFP; Diamond V Original XP; Diamond V, Cedar Rapids, IA) can increase feed intake and milk production in transition dairy cows. To evaluate the effects of various dosages of SCFP, Holstein cows were given individually a supplement containing 0 (n=14), 56 (n=15), or 112 g (n=13) of SCFP daily during morning lockup as a topdressing to their total mixed ration. The supplement consisted of 0, 56, or 112 g of SCFP mixed with 84 g of molasses and 168, 112, or 56 g of corn meal, respectively. Supplement feeding began 28 d before predicted calving date (no less than 14 d) and ended 28 d postpartum, and supplement intake was evaluated daily. Blood samples were collected at d -21, -14, -7, -3, -1, 0, 1, 3, 7, 14, 21, and 28 to measure serum concentrations of macrominerals, metabolites, acute-phase proteins, immunoglobulin, and hormones. Milk weights were measured and milk samples were collected 2 times/wk on nonconsecutive days and analyzed for milk fat, protein, lactose, and somatic cell count (SCC). During the first day after calving, feeding SCFP versus no SCFP decreased serum cortisol concentrations and at least tended to increase supplement intake and serum concentrations of calcium, glucose, urea N, and serum amyloid A. During the first 4 wk postpartum, feeding SCFP versus no SCFP decreased milk SCC and increased milk production and serum phosphorus concentrations. Feeding 112 versus 56 g of SCFP/d did not show additional effects. Feeding SCFP may have a dosage-independent beneficial effect in supporting the physiologic adaptations after parturition, resulting in higher milk production and lower milk SCC. PMID:24612807

  6. Feeding the Transition Dairy Cow 

    E-print Network

    Stokes, Sandra R.

    1999-09-20

    Proper nutrition management during a cow's transition period (from the last 3 weeks of gestation through the first 2 weeks of lactation), is critical to successful lactation. This publication gives details for nutrition management. Two charts list...

  7. Alopecia areata in Eringer cows.

    PubMed

    Timm, Katrin; Rüfenacht, Silvia; von Tscharner, Claudia; Bornand, Valérie F; Doherr, Marcus G; Oevermann, Anna; Flury, Christine; Rieder, Stefan; Hirsbrunner, Gaby; Drögemüller, Cord; Roosje, Petra J

    2010-12-01

    Alopecia areata is a hair loss disorder in humans, dogs and horses with a suspected autoimmune aetiology targeting anagen hair follicles. Alopecia areata is only sporadically reported in cows. Recently, we observed several cases of suspected alopecia areata in Eringer cows. The aim of this study was to confirm the presumptive diagnosis of alopecia areata and to define the clinical phenotype and histopathological patterns, including characterization of the infiltrating inflammatory cells. Twenty Eringer cows with alopecia and 11 Eringer cows without skin problems were included in this study. Affected cows had either generalized or multifocal alopecia or hypotrichosis. The tail, forehead and distal extremities were usually spared. Punch biopsies were obtained from the centre and margin of alopecic lesions and normal haired skin. Histological examination revealed several alterations in anagen hair bulbs. These included peri- and intrabulbar lymphocytic infiltration, peribulbar fibrosis, degenerate matrix cells with clumped melanosomes and pigmentary incontinence. Mild lymphocytic infiltrative mural folliculitis was seen in the inferior segment and isthmus of the hair follicles. Hair shafts were often unpigmented and dysplastic. The large majority of infiltrating lymphocytes were CD3(+) T cells, whereas only occasional CD20(+) lymphocytes were present in the peribulbar infiltrate. Our findings confirm the diagnosis of T-cell-mediated alopecia areata in these cows. Alopecia areata appears to occur with increased frequency in the Eringer breed, but distinct predisposing factors could not be identified. PMID:20626715

  8. Short communication: Effects of dietary nonstructural carbohydrates pre- and postpartum on reproduction of grazing dairy cows.

    PubMed

    Burke, C R; Kay, J K; Phyn, C V C; Meier, S; Lee, J M; Roche, J R

    2010-09-01

    The working hypothesis was that postpartum anovulatory intervals (PPAI) of grazing dairy cows are shortened by inclusion of concentrates that increase the nonstructural carbohydrate content of the transition diet. Dietary treatments were arranged as a 2x2 factorial, with 68 multiparous cows assigned to isoenergetic diets (114 MJ of metabolizable energy/cow per day) of pasture and pasture silage (PreP) or pasture and pasture silage supplemented with 3 kg of dry matter/cow per day a corn- and barley-based concentrate for 36 d prepartum (PreC). After calving, cows within each prepartum diet group were managed on isoenergetic diets (179 MJ of metabolizable energy/cow per day) of either pasture and pasture silage (PostP) or pasture and pasture silage supplemented with 5 kg of dry matter/cow per day a corn- and barley-based concentrate (PostC) for at least 35 d and until reestablishment of ovulatory cycles. Relative to day of calving (d 0), blood samples were collected at least weekly from d -28 to 35 and milk samples were collected twice weekly for progesterone determination to diagnose ovulatory status. The main variable of interest was PPAI, defined as the interval between calving and the first detected increase in milk progesterone (>3 ng/mL), followed by a pattern of progesterone concentrations consistent with onset of an ovulatory cycle. Subsequent mating records, pregnancy testing, and recalving data were also examined. Prepartum diet did not affect reproduction. The PPAI was 8 d shorter and the 6-wk pregnancy rate was 17% greater in PostC cows compared with PostP cows. Measured indicators of metabolic state and energy balance were poorly related to PPAI. The results support the existence of nutritional signals associated with nonstructural carbohydrates in the postpartum diet, independent of energy balance; these signals benefit the physiological mechanisms underlying the timing of first ovulation and possibly subsequent breeding performance. PMID:20723702

  9. Physiological Waterfalls

    ERIC Educational Resources Information Center

    Leith, David E.

    1976-01-01

    Provides background information, defining areas within organ systems where physiological waterfalls exist. Describes pressure-flow relationships of elastic tubes (blood vessels, airways, renal tubules, various ducts). (CS)

  10. Role of Cellular Immunity in Cow's Milk Allergy: Pathogenesis, Tolerance Induction, and Beyond

    PubMed Central

    Garssen, Johan

    2014-01-01

    Food allergy is an aberrant immune-mediated reaction against harmless food substances, such as cow's milk proteins. Due to its very early introduction, cow's milk allergy is one of the earliest and most common food allergies. For this reason cow's milk allergy can be recognized as one of the first indications of an aberrant inflammatory response in early life. Classically, cow's milk allergy, as is true for most other allergies as well, is primarily associated with abnormal humoral immune responses, that is, elevation of specific immunoglobulin E levels. There is growing evidence indicating that cellular components of both innate and adaptive immunity play significant roles during the pathogenesis of cow's milk allergy. This is true for the initiation of the allergic phenotype (stimulation and skewing towards sensitization), development and outgrowth of the allergic disease. This review discusses findings pertaining to roles of cellular immunity in allergic inflammation, and tolerance induction against cow's milk proteins. In addition, a possible interaction between immune mechanisms underlying cow's milk allergy and other types of inflammation (infections and noncommunicable diseases) is discussed. PMID:25002754

  11. a Sensor Based Automatic Ovulation Prediction System for Dairy Cows

    NASA Astrophysics Data System (ADS)

    Mottram, Toby; Hart, John; Pemberton, Roy

    2000-12-01

    Sensor scientists have been successful in developing detectors for tiny concentrations of rare compounds, but the work is rarely applied in practice. Any but the most trivial application of sensors requires a specification that should include a sampling system, a sensor, a calibration system and a model of how the information is to be used to control the process of interest. The specification of the sensor system should ask the following questions. How will the material to be analysed be sampled? What decision can be made with the information available from a proposed sensor? This project provides a model of a systems approach to the implementation of automatic ovulation prediction in dairy cows. A healthy well managed dairy cow should calve every year to make the best use of forage. As most cows are inseminated artificially it is of vital importance mat cows are regularly monitored for signs of oestrus. The pressure on dairymen to manage more cows often leads to less time being available for observation of cows to detect oestrus. This, together with breeding and feeding for increased yields, has led to a reduction in reproductive performance. In the UK the typical dairy farmer could save € 12800 per year if ovulation could be predicted accurately. Research over a number of years has shown that regular analysis of milk samples with tests based on enzyme linked immunoassay (ELISA) can map the ovulation cycle. However, these tests require the farmer to implement a manually operated sampling and analysis procedure and the technique has not been widely taken up. The best potential method of achieving 98% specificity of prediction of ovulation is to adapt biosensor techniques to emulate the ELISA tests automatically in the milking system. An automated ovulation prediction system for dairy cows is specified. The system integrates a biosensor with automatic milk sampling and a herd management database. The biosensor is a screen printed carbon electrode system capable of measuring concentrations of progesterone in milk in the range 0.3-25 ng/ml. The system is operational in the laboratory is described here and will be working on a test farm in the near future to automatically predict the ovulation of dairy cows routinely.

  12. Effects of dry period length on milk production, body condition, metabolites, and hepatic glucose metabolism in dairy cows.

    PubMed

    Weber, C; Losand, B; Tuchscherer, A; Rehbock, F; Blum, E; Yang, W; Bruckmaier, R M; Sanftleben, P; Hammon, H M

    2015-03-01

    Dry period (DP) length affects energy metabolism around calving in dairy cows as well as milk production in the subsequent lactation. The aim of the study was to investigate milk production, body condition, metabolic adaptation, and hepatic gene expression of gluconeogenic enzymes in Holstein cows (>10,000 kg milk/305 d) with 28- (n=18), 56- (n=18), and 90-d DP (n=22) length (treatment groups) in a commercial farm. Cows were fed total mixed rations ad libitum adjusted for far-off (not for 28-d DP) and close-up DP and lactation. Milk yield was recorded daily and body condition score (BCS), back fat thickness (BFT), and body weight (BW) were determined at dry off, 1 wk before expected and after calving, and on wk 2, 4, and 8 postpartum (pp). Blood samples were taken on d -56, -28, -7, 1, 7, 14, 28, and 56 relative to calving to measure plasma concentrations of metabolites and hormones. Liver biopsies (n=11 per treatment) were taken on d -10 and 10 relative to calving to determine glycogen and total liver fat concentration (LFC) and to quantify mRNA levels of pyruvate carboxylase (PC), cytosolic phosphoenolpyruvate carboxykinase, and glucose-6-phosphatase. Time course of milk yield during first 8 wk in lactation differed among treatment. Milk protein content was higher in 28-d than in 90-d DP cows. Milk fat to protein ratio was highest and milk urea was lowest in 90-d DP cows. Differences in BW, BFT, and BCS were predominantly seen before calving with greatest BW, BFT, and BCS in 90-d DP cows. Plasma concentrations of NEFA and BHBA were elevated during the transition period in all cows, and the greatest increase pp was seen in 90-d DP cows. Plasma glucose concentration decreased around calving and was greater in 28-d than in 90-d DP cows. Dry period length also affected plasma concentrations of urea, cholesterol, aspartate transaminase, and glutamate dehydrogenase. Plasma insulin concentration decreased around calving in all cows, but insulin concentration pp was greater in 28-d than in 56-d DP cows. Hepatic glycogen concentration decreased and LFC increased after calving in all cows, and LFC was greater pp in 90-d DP than in 28-d DP cows. Hepatic PC mRNA abundance pp tended to increase most in 90-d DP cows. Changes on glucose metabolism were more balanced in cows with a reduced DP, whereas cows with extended DP and elevated body condition indicated greatest metabolic changes according to lipid and glucose metabolism during the transition period. PMID:25547307

  13. Anti-inflammatory salicylate treatment alters the metabolic adaptations to lactation in dairy cattle

    PubMed Central

    Farney, Jaymelynn K.; Mamedova, Laman K.; Coetzee, Johann F.; KuKanich, Butch; Sordillo, Lorraine M.; Stoakes, Sara K.; Minton, J. Ernest; Hollis, Larry C.

    2013-01-01

    Adapting to the lactating state requires metabolic adjustments in multiple tissues, especially in the dairy cow, which must meet glucose demands that can exceed 5 kg/day in the face of negligible gastrointestinal glucose absorption. These challenges are met through the process of homeorhesis, the alteration of metabolic setpoints to adapt to a shift in physiological state. To investigate the role of inflammation-associated pathways in these homeorhetic adaptations, we treated cows with the nonsteroidal anti-inflammatory drug sodium salicylate (SS) for the first 7 days of lactation. Administration of SS decreased liver TNF-? mRNA and marginally decreased plasma TNF-? concentration, but plasma eicosanoids and liver NF-?B activity were unaltered during treatment. Despite the mild impact on these inflammatory markers, SS clearly altered metabolic function. Plasma glucose concentration was decreased by SS, but this was not explained by a shift in hepatic gluconeogenic gene expression or by altered milk lactose secretion. Insulin concentrations decreased in SS-treated cows on day 7 compared with controls, which was consistent with the decline in plasma glucose concentration. The revised quantitative insulin sensitivity check index (RQUICKI) was then used to assess whether altered insulin sensitivity may have influenced glucose utilization rate with SS. The RQUICKI estimate of insulin sensitivity was significantly elevated by SS on day 7, coincident with the decline in plasma glucose concentration. Salicylate prevented postpartum insulin resistance, likely causing excessive glucose utilization in peripheral tissues and hypoglycemia. These results represent the first evidence that inflammation-associated pathways are involved in homeorhetic adaptations to lactation. PMID:23678026

  14. Evaluation of F1 Cows Sired by Brahman, Boran, and Tuli Bulls for Reproductive and Maternal Performance Traits and Cow Longevity 

    E-print Network

    Muntean, Carl

    2011-08-08

    rate, CCB, CCW, CW, and BCS were evaluated using a model that consisted of sire of cow breed, dam of cow breed, and calf's birth year/age of cow as fixed effects. Cow within sire of cow within sire breed of cow and sire of cow within sire breed of cow...

  15. Nasal Physiology

    MedlinePLUS

    ... Introduction The physiologic function of the nose includes respiration, conditioning inspired air, vocal resonance, olfaction, nasal resistance, ... airway, and ventilation and drainage of the sinuses. RESPIRATION The nose is a natural pathway for breathing. ...

  16. Feeding the Cow and Calf. 

    E-print Network

    Maddox, L. A. Jr.

    1965-01-01

    Feed Efficiency, 9 Supplemental Feeding, 12 Feeding During Cold Weather, 13 Feeding for Milk Production, 14 1 Feeding During Drouth, 14 APPnoxmATELy 60 percent of the cost of produc- ing a calf is in feeding the cow and calf. This major cost... in com- mercial beef operations. A wide range of nutri- tional levels that cause the cow to vary from a loss of 1 pouncl to a gain of 2 pountls per day in her I~otly weight while nursing a calf makes specific feeding recommendations for milk...

  17. The effect of heat waves on dairy cow mortality.

    PubMed

    Vitali, A; Felici, A; Esposito, S; Bernabucci, U; Bertocchi, L; Maresca, C; Nardone, A; Lacetera, N

    2015-07-01

    This study investigated the mortality of dairy cows during heat waves. Mortality data (46,610 cases) referred to dairy cows older than 24mo that died on a farm from all causes from May 1 to September 30 during a 6-yr period (2002-2007). Weather data were obtained from 12 weather stations located in different areas of Italy. Heat waves were defined for each weather station as a period of at least 3 consecutive days, from May 1 to September 30 (2002-2007), when the daily maximum temperature exceeded the 90th percentile of the reference distribution (1971-2000). Summer days were classified as days in heat wave (HW) or not in heat wave (nHW). Days in HW were numbered to evaluate the relationship between mortality and length of the wave. Finally, the first 3 nHW days after the end of a heat wave were also considered to account for potential prolonged effects. The mortality risk was evaluated using a case-crossover design. A conditional logistic regression model was used to calculate odds ratio and 95% confidence interval for mortality recorded in HW compared with that recorded in nHW days pooled and stratified by duration of exposure, age of cows, and month of occurrence. Dairy cows mortality was greater during HW compared with nHW days. Furthermore, compared with nHW days, the risk of mortality continued to be higher during the 3 d after the end of HW. Mortality increased with the length of the HW. Considering deaths stratified by age, cows up to 28mo were not affected by HW, whereas all the other age categories of older cows (29-60, 61-96, and >96mo) showed a greater mortality when exposed to HW. The risk of death during HW was higher in early summer months. In particular, the highest risk of mortality was observed during June HW. Present results strongly support the implementation of adaptation strategies which may limit heat stress-related impairment of animal welfare and economic losses in dairy cow farm during HW. PMID:25958287

  18. Cold adaptations.

    PubMed

    Launay, Jean-Claude; Savourey, Gustave

    2009-07-01

    Nowdays, occupational and recreational activities in cold environments are common. Exposure to cold induces thermoregulatory responses like changes of behaviour and physiological adjustments to maintain thermal balance either by increasing metabolic heat production by shivering and/or by decreasing heat losses consecutive to peripheral cutaneous vasoconstriction. Those physiological responses present a great variability among individuals and depend mainly on biometrical characteristics, age, and general cold adaptation. During severe cold exposure, medical disorders may occur such as accidental hypothermia and/or freezing or non-freezing cold injuries. General cold adaptations have been qualitatively classified by Hammel and quantitatively by Savourey. This last classification takes into account the quantitative changes of the main cold reactions: higher or lower metabolic heat production, higher or lesser heat losses and finally the level of the core temperature observed at the end of a standardized exposure to cold. General cold adaptations observed previously in natives could also be developed in laboratory conditions by continuous or intermittent cold exposures. Beside general cold adaptation, local cold adaptation exists and is characterized by a lesser decrease of skin temperature, a more pronounced cold induced vasodilation, less pain and a higher manual dexterity. Adaptations to cold may reduce the occurrence of accidents and improve human performance as surviving in the cold. The present review describes both general and local cold adaptations in humans and how they are of interest for cold workers. PMID:19531907

  19. Regulatory Physiology

    NASA Technical Reports Server (NTRS)

    Lane, Helen W.; Whitson, Peggy A.; Putcha, Lakshmi; Baker, Ellen; Smith, Scott M.; Stewart, Karen; Gretebeck, Randall; Nimmagudda, R. R.; Schoeller, Dale A.; Davis-Street, Janis

    1999-01-01

    As noted elsewhere in this report, a central goal of the Extended Duration Orbiter Medical Project (EDOMP) was to ensure that cardiovascular and muscle function were adequate to perform an emergency egress after 16 days of spaceflight. The goals of the Regulatory Physiology component of the EDOMP were to identify and subsequently ameliorate those biochemical and nutritional factors that deplete physiological reserves or increase risk for disease, and to facilitate the development of effective muscle, exercise, and cardiovascular countermeasures. The component investigations designed to meet these goals focused on biochemical and physiological aspects of nutrition and metabolism, the risk of renal (kidney) stone formation, gastrointestinal function, and sleep in space. Investigations involved both ground-based protocols to validate proposed methods and flight studies to test those methods. Two hardware tests were also completed.

  20. Physiology of man and animals in the Tenth Five-Year Plan: Proceedings of the Thirteenth Congress of the I. P. Pavlov All-Union Physiological Society

    NASA Technical Reports Server (NTRS)

    Lange, K. A.

    1980-01-01

    Research in the field of animal and human physiology is reviewed. The following topics on problems of physiological science and related fields of knowledge are discussed: neurophysiology and higher nervous activity, physiology of sensory systems, physiology of visceral systems, evolutionary and ecological physiology, physiological cybernetics, computer application in physiology, information support of physiological research, history and theory of development of physiology. Also discussed were: artificial intelligence, physiological problems of reflex therapy, correlation of structure and function of the brain, adaptation and activity, microcirculation, and physiological studies in nerve and mental diseases.

  1. Salinity adaptation of the invasive New Zealand mud snail (Potamopyrgus antipodarum) in the Columbia River estuary (Pacific Northwest, USA): physiological and molecular studies

    USGS Publications Warehouse

    Hoy, Marshal; Boese, Bruce L.; Taylor, Louise; Reusser, Deborah; Rodriguez, Rusty

    2012-01-01

    In this study, we examine salinity stress tolerances of two populations of the invasive species New Zealand mud snail Potamopyrgus antipodarum, one population from a high salinity environment in the Columbia River estuary and the other from a fresh water lake. In 1996, New Zealand mud snails were discovered in the tidal reaches of the Columbia River estuary that is routinely exposed to salinity at near full seawater concentrations. In contrast, in their native habitat and throughout its spread in the western US, New Zealand mud snails are found only in fresh water ecosystems. Our aim was to determine whether the Columbia River snails have become salt water adapted. Using a modification of the standard amphipod sediment toxicity test, salinity tolerance was tested using a range of concentrations up to undiluted seawater, and the snails were sampled for mortality at daily time points. Our results show that the Columbia River snails were more tolerant of acute salinity stress with the LC50 values averaging 38 and 22 Practical Salinity Units for the Columbia River and freshwater snails, respectively. DNA sequence analysis and morphological comparisons of individuals representing each population indicate that they were all P. antipodarum. These results suggest that this species is salt water adaptable and in addition, this investigation helps elucidate the potential of this aquatic invasive organism to adapt to adverse environmental conditions.

  2. Comparison of F1 cows sired by Brahman, Boran and Tuli bulls for reproductive, maternal, and cow longevity traits 

    E-print Network

    Maiga, Assalia Hassimi

    2007-04-25

    included sire breed of cow, dam breed of cow, and calf�s birth year/age of cow; random effects included cow and sire of cow. BW and WW were evaluated using the same model and adding gender for both and age for WW. All two-way interactions were tested...

  3. ALMOND MILK: A POTENTIAL THERAPEUTIC WEAPON AGAINST COW?S MILK PROTEIN ALLERGY.

    PubMed

    Cuppari, C; Manti, S; Salpietro, A; Dugo, G; Gitto, E; Arrigo, T; Sturiale, M; Salpietro, C

    2015-01-01

    Food allergy is defined as an adverse health effect arising from a specific immune response that occurs reproducibly following exposure to a given food. Cow?s milk protein allergy results from an immunological reaction to one or more milk proteins. The principle key in the treatment of cow?s milk protein allergy is the dietary elimination of cow?s milk protein. Although hydrolyzed and elemental formulas are appropriate replacements, other milk products, including almond milk adequately integrated, could be administered. Here, in the light of encouraging results from our study, we focused on the anti-inflammatory and anti-oxidant properties of almond milk and we also believe that almond milk might be considered as a potential alternative in cow?s milk protein allergy treatment. PMID:26634581

  4. Microbial physiology and soil CO2 efflux after 9 years of soil warming in a temperate forest – no indications for thermal adaptations

    PubMed Central

    SCHINDLBACHER, ANDREAS; SCHNECKER, JÖRG; TAKRITI, MOUNIR; BORKEN, WERNER; WANEK, WOLFGANG

    2015-01-01

    Thermal adaptations of soil microorganisms could mitigate or facilitate global warming effects on soil organic matter (SOM) decomposition and soil CO2 efflux. We incubated soil from warmed and control subplots of a forest soil warming experiment to assess whether 9 years of soil warming affected the rates and the temperature sensitivity of the soil CO2 efflux, extracellular enzyme activities, microbial efficiency, and gross N mineralization. Mineral soil (0–10 cm depth) was incubated at temperatures ranging from 3 to 23 °C. No adaptations to long-term warming were observed regarding the heterotrophic soil CO2 efflux (R10 warmed: 2.31 ± 0.15 ?mol m?2 s?1, control: 2.34 ± 0.29 ?mol m?2 s?1; Q10 warmed: 2.45 ± 0.06, control: 2.45 ± 0.04). Potential enzyme activities increased with incubation temperature, but the temperature sensitivity of the enzymes did not differ between the warmed and the control soils. The ratio of C : N acquiring enzyme activities was significantly higher in the warmed soil. Microbial biomass-specific respiration rates increased with incubation temperature, but the rates and the temperature sensitivity (Q10 warmed: 2.54 ± 0.23, control 2.75 ± 0.17) did not differ between warmed and control soils. Microbial substrate use efficiency (SUE) declined with increasing incubation temperature in both, warmed and control, soils. SUE and its temperature sensitivity (Q10 warmed: 0.84 ± 0.03, control: 0.88 ± 0.01) did not differ between warmed and control soils either. Gross N mineralization was invariant to incubation temperature and was not affected by long-term soil warming. Our results indicate that thermal adaptations of the microbial decomposer community are unlikely to occur in C-rich calcareous temperate forest soils. PMID:26046333

  5. Microbial physiology and soil CO2 efflux after 9 years of soil warming in a temperate forest - no indications for thermal adaptations.

    PubMed

    Schindlbacher, Andreas; Schnecker, Jörg; Takriti, Mounir; Borken, Werner; Wanek, Wolfgang

    2015-11-01

    Thermal adaptations of soil microorganisms could mitigate or facilitate global warming effects on soil organic matter (SOM) decomposition and soil CO2 efflux. We incubated soil from warmed and control subplots of a forest soil warming experiment to assess whether 9 years of soil warming affected the rates and the temperature sensitivity of the soil CO2 efflux, extracellular enzyme activities, microbial efficiency, and gross N mineralization. Mineral soil (0-10 cm depth) was incubated at temperatures ranging from 3 to 23 °C. No adaptations to long-term warming were observed regarding the heterotrophic soil CO2 efflux (R10 warmed: 2.31 ± 0.15 ?mol m(-2)  s(-1) , control: 2.34 ± 0.29 ?mol m(-2)  s(-1) ; Q10 warmed: 2.45 ± 0.06, control: 2.45 ± 0.04). Potential enzyme activities increased with incubation temperature, but the temperature sensitivity of the enzymes did not differ between the warmed and the control soils. The ratio of C : N acquiring enzyme activities was significantly higher in the warmed soil. Microbial biomass-specific respiration rates increased with incubation temperature, but the rates and the temperature sensitivity (Q10 warmed: 2.54 ± 0.23, control 2.75 ± 0.17) did not differ between warmed and control soils. Microbial substrate use efficiency (SUE) declined with increasing incubation temperature in both, warmed and control, soils. SUE and its temperature sensitivity (Q10 warmed: 0.84 ± 0.03, control: 0.88 ± 0.01) did not differ between warmed and control soils either. Gross N mineralization was invariant to incubation temperature and was not affected by long-term soil warming. Our results indicate that thermal adaptations of the microbial decomposer community are unlikely to occur in C-rich calcareous temperate forest soils. PMID:26046333

  6. Effect of rumen fill on intake of fresh perennial ryegrass in young and mature dairy cows grazing or zero-grazing fresh perennial ryegrass.

    PubMed

    Boudon, A; Peyraud, J-L; Faverdin, P; Delagarde, R; Delaby, L; Chaves, A V

    2009-12-01

    Rumen fill may be a strong intake constraint for dairy cows fed on pasture, even though pasture is highly digestible in the grasslands of temperate climates. This constraint may also depend on the cows' maturity. Moreover, indoor feeding of fresh herbage may not always be a good model for the study of intake regulation at grazing. To test these hypotheses, four mature (6.3 ± 0.72 year old) and four young (3.8 ± 0.20 year old) dairy cows were offered fresh perennial ryegrass indoors or at grazing. The impact of rumen fill on intake was evaluated by addition of rumen inert bulk (RIB; coconut fiber, 15 l) compared to a control. The experimental design was a double 4 × 4 Latin square with four 14-day periods and a 2 × 2 factorial arrangement of two feeding methods (indoor feeding v. grazing), combined with the addition, or not, of RIB (RIB v. control), repeated for four mature and four young cows. Digestibility of offered herbage was 0.81. The average ytterbium measured dry matter intake (Yb DMI) was 19.0 and 15.5 kg/day for mature and young cows respectively (P = 0.019). The effect of RIB on predicted Yb DMI interacted with feeding method and cow age (P = 0.043). The presence of RIB decreased Yb DMI by 4.4 kg/day in mature cows at grazing and by 3.4 kg/day in young cows indoors, whereas it did not affect the Yb DMI of mature cows indoors or grazing young cows. Both grazing and young age constituted a clear constraint on the feeding behavior of the cows. Grazing cows had fewer ingestion and rumination sequences, which were longer and less evenly distributed throughout the day and night. Young cows had lower intake rates that were less adaptable to the feeding method and the presence of RIB. Mature cows clearly decreased their daily intake rate at grazing compared to indoor feeding, and with RIB compared to control, whereas the intake rate of young cows did not vary. These results indicate that rumen fill can represent a constraint on intake in grazing cows, even when highly digestible perennial ryegrass is offered. The study also shows that the impact of RIB on intake is highly dependent upon other constraints applied to the chewing behavior, which in this experiment were methods of offering herbage and cow age. PMID:22443555

  7. Achieving Body Weight Adjustments for Feeding Status and Pregnant or Non-Pregnant Condition in Beef Cows

    PubMed Central

    Gionbelli, Mateus P.; Duarte, Marcio S.; Valadares Filho, Sebastião C.; Detmann, Edenio; Chizzotti, Mario L.; Rodrigues, Felipe C.; Zanetti, Diego; Gionbelli, Tathyane R. S.; Machado, Marcelo G.

    2015-01-01

    Background Beef cows herd accounts for 70% of the total energy used in the beef production system. However, there are still limited studies regarding improvement of production efficiency in this category, mainly in developing countries and in tropical areas. One of the limiting factors is the difficulty to obtain reliable estimates of weight variation in mature cows. This occurs due to the interaction of weight of maternal tissues with specific physiological stages such as pregnancy. Moreover, variation in gastrointestinal contents due to feeding status in ruminant animals is a major source of error in body weight measurements. Objectives Develop approaches to estimate the individual proportion of weight from maternal tissues and from gestation in pregnant cows, adjusting for feeding status and stage of gestation. Methods and Findings Dataset of 49 multiparous non-lactating Nellore cows (32 pregnant and 17 non-pregnant) were used. To establish the relationships between the body weight, depending on the feeding status of pregnant and non-pregnant cows as a function of days of pregnancy, a set of general equations was tested, based on theoretical suppositions. We proposed the concept of pregnant compound (PREG), which represents the weight that is genuinely related to pregnancy. The PREG includes the gravid uterus minus the non-pregnant uterus plus the accretion in udder related to pregnancy. There was no accretion in udder weight up to 238 days of pregnancy. By subtracting the PREG from live weight of a pregnant cow, we obtained estimates of the weight of only maternal tissues in pregnant cows. Non-linear functions were adjusted to estimate the relationship between fasted, non-fasted and empty body weight, for pregnant and non-pregnant cows. Conclusions Our results allow for estimating the actual live weight of pregnant cows and their body constituents, and subsequent comparison as a function of days of gestation and feeding status. PMID:25793770

  8. Neonatal renal physiology.

    PubMed

    Sulemanji, Mustafa; Vakili, Khashayar

    2013-11-01

    The renal system plays a tremendous role in growth and development of infants and children. The kidney itself also undergoes a maturation process as it transitions from the fetal to the extrauterine environment. Renal function continues to undergo further adaptive changes in the neonatal period. It is important for the clinician caring for neonates to be aware of the expected fluid shifts, electrolyte handling, and renal functional capacity as these "normal" changes will become quite relevant when medical or surgical pathology is present. The preterm neonates are especially vulnerable due to their functionally immature kidneys. Renal function in the preterm neonate is not only immature at birth but there is a significant delay in the renal function to achieve its full capacity. This review highlights the physiologic adaptations of the kidney and its effects on the body during the neonatal period. PMID:24331094

  9. Predictive Models for Regional Hepatic Function Based on 99mTc-IDA SPECT and Local Radiation Dose for Physiologic Adaptive Radiation Therapy

    SciTech Connect

    Wang, Hesheng; Feng, Mary; Frey, Kirk A.; Ten Haken, Randall K.; Lawrence, Theodore S.; Cao, Yue

    2013-08-01

    Purpose: High-dose radiation therapy (RT) for intrahepatic cancer is limited by the development of liver injury. This study investigated whether regional hepatic function assessed before and during the course of RT using 99mTc-labeled iminodiacetic acid (IDA) single photon emission computed tomography (SPECT) could predict regional liver function reserve after RT. Methods and Materials: Fourteen patients treated with RT for intrahepatic cancers underwent dynamic 99mTc-IDA SPECT scans before RT, during, and 1 month after completion of RT. Indocyanine green (ICG) tests, a measure of overall liver function, were performed within 1 day of each scan. Three-dimensional volumetric hepatic extraction fraction (HEF) images of the liver were estimated by deconvolution analysis. After coregistration of the CT/SPECT and the treatment planning CT, HEF dose–response functions during and after RT were generated. The volumetric mean of the HEFs in the whole liver was correlated with ICG clearance time. Three models, dose, priori, and adaptive models, were developed using multivariate linear regression to assess whether the regional HEFs measured before and during RT helped predict regional hepatic function after RT. Results: The mean of the volumetric liver HEFs was significantly correlated with ICG clearance half-life time (r=?0.80, P<.0001), for all time points. Linear correlations between local doses and regional HEFs 1 month after RT were significant in 12 patients. In the priori model, regional HEF after RT was predicted by the planned dose and regional HEF assessed before RT (R=0.71, P<.0001). In the adaptive model, regional HEF after RT was predicted by regional HEF reassessed during RT and the remaining planned local dose (R=0.83, P<.0001). Conclusions: 99mTc-IDA SPECT obtained during RT could be used to assess regional hepatic function and helped predict post-RT regional liver function reserve. This could support individualized adaptive radiation treatment strategies to maximize tumor control and minimize the risk of liver damage.

  10. Predictive Models for Regional Hepatic Function Based upon 99mTc-IDA SPECT and Local Radiation Dose for Physiological Adaptive RT

    PubMed Central

    Wang, Hesheng; Feng, Mary; Frey, Kirk A.; Ten Haken, Randall K.; Lawrence, Theodore S.; Cao, Yue

    2013-01-01

    Purpose High dose radiation therapy (RT) for intrahepatic cancer is limited by the development of liver injury. This study investigated whether regional hepatic function assessed prior to and during the course of RT using 99mTc-labeled immindodiacetic acid (IDA) SPECT could predict regional liver function reserve after RT. Methods and Materials Fourteen patients treated with RT for intrahepatic cancers underwent dynamic 99mTc-IDA SPECT scans prior to RT, during, and one month after completion of RT. Indocyanine green (ICG) tests (a measure of overall liver function) were performed within 1 day of each scan. 3D volumetric hepatic extraction fraction (HEF) images of the liver were estimated by deconvolution analysis. After co-registration of the CT/SPECT and the treatment planning CT, HEF dose-response functions during and post-RT were generated. The volumetric mean of the HEFs in the whole liver was correlated with ICG clearance time. Three models, Dose, Priori and Adaptive models, were developed using multivariate linear regression to assess whether the regional HEFs measured before and during RT helped predict regional hepatic function post-RT. Results The mean of the volumetric liver HEFs was significantly correlated with ICG clearance half-life time (r = ?0.80, p<0.0001), for all time points. Linear correlations between local doses and regional HEFs one month post-RT were significant in 12 patients. In the priori model, regional HEF post-RT was predicted by the planned dose and regional HEF assessed prior to RT (R=0.71, p<0.0001). In the adaptive model, regional HEF post-RT was predicted by regional HEF re-assessed during RT and the remaining planned local dose (R=0.83, p<0.0001). Conclusions 99mTc-IDA SPECT obtained during RT could be used to assess regional hepatic function and helped predict post-RT regional liver function reserve. This could support individualized adaptive radiation treatment strategies to maximize tumor control and minimize the risk of liver damage. PMID:23688813

  11. Utilization of Vitamin A by Dairy Cows

    E-print Network

    Fraps, G. S. (George Stronach)

    1937-01-01

    A value of dried alfalfa and corn silage usually appeared in the m-ilk on a daily intake of 1,213,500 to 946,700 U. S. P. 1934 units per cow. Peterson et a1 (12) stated that only about 2% of the carotene appeared in the butterfat when the cow... the cows consisted of 60 per cent yellow corn, 27 per cent cottonseed meal, 10 per cent wheat bran, 2 per cent pulverized oyster shell, and 1 per cent salt, made available at the rate of approximately 29 pounds for each pound of milk per cow daily. One...

  12. Physiological and Proteomic Adaptation of “Aromatoleum aromaticum” EbN1 to Low Growth Rates in Benzoate-Limited, Anoxic Chemostats

    PubMed Central

    Trautwein, Kathleen; Lahme, Sven; Wöhlbrand, Lars; Feenders, Christoph; Mangelsdorf, Kai; Harder, Jens; Steinbüchel, Alexander; Blasius, Bernd; Reinhardt, Richard

    2012-01-01

    “Aromatoleum aromaticum” EbN1 was cultivated at different growth rates in benzoate-limited chemostats under nitrate-reducing conditions. Physiological characteristics, proteome dynamics, phospholipid-linked fatty acid (PLFA) composition, and poly(3-hydroxybutyrate) (PHB) content were analyzed in steady-state cells at low (?low) (0.036 h?1), medium (?med) (0.108 h?1), and high (?high) (0.180 h?1) growth rates. A positive correlation to growth rate was observed for cellular parameters (cell size, and DNA and protein contents). The free energy consumed for biomass formation steadily increased with growth rate. In contrast, the energy demand for maintenance increased only from ?low to ?med and then remained constant until ?high. The most comprehensive proteomic changes were observed at ?low compared to ?high. Uniformly decreased abundances of protein components of the anaerobic benzoyl coenzyme A (benzoyl-CoA) pathway, central carbon metabolism, and information processing agree with a general deceleration of benzoate metabolism and cellular processes in response to slow growth. In contrast, increased abundances were observed at ?low for diverse catabolic proteins and components of uptake systems in the absence of the respective substrate (aromatic or aliphatic compounds) and for proteins involved in stress responses. This potential catabolic versatility and stress defense during slow growth may be interpreted as preparation for future needs. PMID:22366417

  13. Respiratory Physiology on a Chip

    PubMed Central

    Kumar Mahto, Sanjeev; Tenenbaum-Katan, Janna; Sznitman, Josué

    2012-01-01

    Our current understanding of respiratory physiology and pathophysiological mechanisms of lung diseases is often limited by challenges in developing in vitro models faithful to the respiratory environment, both in cellular structure and physiological function. The recent establishment and adaptation of microfluidic-based in vitro devices (?FIVDs) of lung airways have enabled a wide range of developments in modern respiratory physiology. In this paper, we address recent efforts over the past decade aimed at advancing in vitro models of lung structure and airways using microfluidic technology and discuss their applications. We specifically focus on ?FIVDs covering four major areas of respiratory physiology, namely, artificial lungs (AL), the air-liquid interface (ALI), liquid plugs and cellular injury, and the alveolar-capillary barrier (ACB). PMID:24278686

  14. Intestinal malrotation with suspected cow’s milk allergy: a case report

    PubMed Central

    2012-01-01

    Background Intestinal malrotation is an incomplete rotation of the intestine. Failure to rotate leads to abnormalities in intestinal positioning and attachment that leave obstructing bands across the duodenum and a narrow pedicle for the midgut loop, thus making it susceptible to volvulus. One of the important differential diagnoses for malrotation is an allergy to cow’s milk. Several studies have described infants with surgical gastrointestinal diseases and cow’s milk allergy. However, to our knowledge, no study has reported infants with intestinal malrotation who have been symptomatic before surgery was performed and have been examined by allergen-specific lymphocyte stimulation test and food challenge tests with long-term follow-up. Case presentation The patient was a Japanese male born at 39 weeks of gestation. He was breast-fed and received commercial cow’s milk supplementation starting the day of birth and was admitted to our hospital at 6 days of age due to bilious vomiting. Plain abdominal radiography showed a paucity of gas in the distal bowel. Because we demonstrated malpositioning of the intestine by barium enema, we repositioned the bowel in a normal position by laparotomy. The patient was re-started on only breast milk 2 days post surgery because we suspected the presence of a cow’s milk allergy, and the results of an allergen-specific lymphocyte stimulation test showed a marked increase in lymphocyte response to kappa-casein. At 5 months of age, the patient was subjected to a cow’s milk challenge test. After the patient began feeding on cow’s milk, he had no symptoms and his laboratory investigations showed no abnormality. In addition, because the patient showed good weight gain and no symptoms with increased cow’s milk intake after discharge, we concluded that the present case was not the result of a cow’s milk allergy. At 1 year, the patient showed favorable growth and development, and serum allergy investigations revealed no reaction to cow’s milk. Conclusion When physicians encounter infants with surgical gastrointestinal disease, including intestinal malrotation, they should consider cow’s milk allergy as a differential diagnosis or complication and should utilize food challenge tests for a definitive diagnosis. PMID:22943656

  15. Larval exposure to 4-nonylphenol and 17beta-estradiol affects physiological and behavioral development of seawater adaptation in Atlantic salmon smolts.

    PubMed

    Lerner, Darren T; Björnsson, Björn Thrandur; McCormick, Stephen D

    2007-06-15

    Population declines of anadromous salmonids are attributed to anthropogenic disturbances including dams, commercial and recreational fisheries, and pollutants, such as estrogenic compounds. Nonylphenol (NP), a xenoestrogen, is widespread in the aquatic environment due to its use in agricultural, industrial, and household products. We exposed Atlantic salmon yolk-sac larvae to waterborne 10 or 100 microg L(-1) NP (NP-L or NP-H, respectively), 2 microg L(-1) 17beta-estradiol (E2), or vehicle, for 21 days to investigate their effects on smolt physiology and behavior 1 year later. NP-H caused approximately 50% mortality during exposure, 30 days after exposure, and 60 days after exposure. Mortality rates of NP-L and E2 fish were not affected until 60 days after treatment, when they were 4-fold greater than those of controls. Treatment with NP-L or E2 as yolk-sac larvae decreased gill sodium-potassium-activated adenosine triphosphatase (Na+,K(+)-ATPase) activity and seawater (SW) tolerance during smolt development, 1 year after exposure. Exposure to NP-L and E2 resulted in a latency to enter SW and reduced preference for SW approximately 2- and 5-fold, respectively. NP-L-exposed fish had 20% lower plasma insulin-like growth factor I (IGF-I) levels and 35% lower plasma triiodothyronine (T3). Plasma growth hormone and thyroxine (T4) were unaffected. Exposure to E2 did not affect plasma levels of IGF-I, GH, T3, or T4. Both treatment groups exhibited increased plasma cortisol and decreased osmoregulatory capacity in response to a handling stressor. These results suggest that early exposure to environmentally relevant concentrations of NP, and other estrogenic compounds, can cause direct and delayed mortalities and that this exposure can have long-term, "organizational" effects on life-history events in salmonids. PMID:17626455

  16. Effects of corn and soybean meal types on rumen fermentation, nitrogen metabolism and productivity in dairy cows.

    PubMed

    Shen, J S; Song, L J; Sun, H Z; Wang, B; Chai, Z; Chacher, B; Liu, J X

    2015-03-01

    Twelve multiparous Holstein dairy cows in mid-lactation were selected for a replicated 4×4 Latin square design with a 2 ×2 factorial arrangement to investigate the effects of corn and soybean meal (SBM) types on rumen fermentation, N metabolism and lactation performance in dairy cows. Two types of corn (dry ground [DGC] and steam-flaked corn [SFC]) and two types of SBM (solvent-extracted and heat-treated SBM) with different ruminal degradation rates and extents were used to formulate four diets with the same basal ingredients. Each period lasted for 21 days, including 14 d for adaptation and 7 d for sample collection. Cows receiving SFC had a lower dry matter (DM) and total N intake than those fed DGC. However, the milk yield and milk protein yield were not influenced by the corn type, resulting in higher feed and N utilization efficiency in SFC-fed cows than those receiving DGC. Ruminal acetate concentrations was greater and total volatile fatty acids concentrations tended to be greater for cows receiving DGC relative to cows fed SFC, but milk fat content was not influenced by corn type. The SFC-fed cows had lower ruminal ammonia-N, less urea N in their blood and milk, and lower fecal N excretion than those on DGC. Compared with solvent-extracted SBM-fed cows, cows receiving heat-treated SBM had lower microbial protein yield in the rumen, but similar total tract apparent nutrient digestibility, N metabolism measurements, and productivity. Excessive supply of metabolizable protein in all diets may have caused the lack of difference in lactation performance between SBM types. Results of the present study indicated that increasing the energy degradability in the rumen could improve feed efficiency, and reduce environmental pollution. PMID:25656206

  17. Dairy cow manure digester and cogenerator performance

    SciTech Connect

    Pigg, D.L.; Vetter, R.L.

    1985-01-01

    A 94 m/sup 3/ mesophilic digester with a 15 kW engine-generator was monitored. The average manure collected was 6.48 kg VS/cow/day. An ultimate methane yield (Bo) of 0.25 L CH4/g VS was calculated. The potential gross energy production was determined to be 3 kWh/cow/day.

  18. Improving cow herd production through early weaning

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Early weaning, in spring calving production systems, has intrigued many producers to consider this alternative management practice especially during extended droughts and as a tool to promote stayability within a cow herd for young developing cows. The first objective of this study was to evaluate ...

  19. 33 CFR 117.965 - Cow Bayou.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Cow Bayou. 117.965 Section 117.965 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Texas § 117.965 Cow Bayou. The draws of the Orange...

  20. 33 CFR 117.965 - Cow Bayou.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Cow Bayou. 117.965 Section 117.965 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Texas § 117.965 Cow Bayou. The draws of the Orange...

  1. 33 CFR 117.965 - Cow Bayou.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Cow Bayou. 117.965 Section 117.965 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Texas § 117.965 Cow Bayou. The draws of the Orange...

  2. 33 CFR 117.965 - Cow Bayou.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Cow Bayou. 117.965 Section 117.965 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Texas § 117.965 Cow Bayou. The draws of the Orange...

  3. 33 CFR 117.965 - Cow Bayou.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Cow Bayou. 117.965 Section 117.965 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Texas § 117.965 Cow Bayou. The draws of the Orange...

  4. Root physiological adaptations involved in enhancing P assimilation in mining and non-mining ecotypes of Polygonum hydropiper grown under organic P media

    PubMed Central

    Ye, Daihua; Li, Tingxuan; Zheng, Zicheng; Zhang, Xizhou; Chen, Guangdeng; Yu, Haiying

    2015-01-01

    It is important to seek out plant species, high in phosphorus (P) uptake, for phytoremediation of P-enriched environments with a large amount of organic P (Po). P assimilation characteristics and the related mechanisms of Polygonum hydropiper were investigated in hydroponic media containing various concentrations of Po (1–8 mmol L-1) supplied as phytate. The mining ecotype (ME) showed significantly higher biomass in both shoots and roots compared to the non-mining ecotype (NME) at 4, 6, and 8 m mol L-1. Shoot P content of both ecotypes increased up to 4 mmol L-1 while root P content increased continually up to 8 mmol L-1 for the ME and up to 6 mmol L-1 for the NME. Root P content of the ME exceeded 1% dry weight under 6 and 8 mmol L-1. The ME had significantly higher P accumulation in both shoots and roots compared to the NME supplied with 6 and 8 mmol L-1. The ME showed higher total root length, specific root length, root surface area, root volume, and displayed significantly greater root length, root surface area, and root volume of lateral roots compared to the NME grown in all Po treatments. Average diameter of lateral roots was 0.17–19 mm for the ME and 0.18–0.21 mm for the NME. Greater acid phosphatase and phytase activities were observed in the ME grown under different levels of Po relative to the NME. This indicated fine root morphology, enhanced acid phosphatase and phytase activities might be adaptations to high Po media. Results from this study establish that the ME of P. hydropiper is capable of assimilating P from Po media and is a potential material for phytoremediation of polluted area with high Po. PMID:25699065

  5. Root physiological adaptations involved in enhancing P assimilation in mining and non-mining ecotypes of Polygonum hydropiper grown under organic P media.

    PubMed

    Ye, Daihua; Li, Tingxuan; Zheng, Zicheng; Zhang, Xizhou; Chen, Guangdeng; Yu, Haiying

    2015-01-01

    It is important to seek out plant species, high in phosphorus (P) uptake, for phytoremediation of P-enriched environments with a large amount of organic P (Po). P assimilation characteristics and the related mechanisms of Polygonum hydropiper were investigated in hydroponic media containing various concentrations of Po (1-8 mmol L(-1)) supplied as phytate. The mining ecotype (ME) showed significantly higher biomass in both shoots and roots compared to the non-mining ecotype (NME) at 4, 6, and 8 m mol L(-1). Shoot P content of both ecotypes increased up to 4 mmol L(-1) while root P content increased continually up to 8 mmol L(-1) for the ME and up to 6 mmol L(-1) for the NME. Root P content of the ME exceeded 1% dry weight under 6 and 8 mmol L(-1). The ME had significantly higher P accumulation in both shoots and roots compared to the NME supplied with 6 and 8 mmol L(-1). The ME showed higher total root length, specific root length, root surface area, root volume, and displayed significantly greater root length, root surface area, and root volume of lateral roots compared to the NME grown in all Po treatments. Average diameter of lateral roots was 0.17-19 mm for the ME and 0.18-0.21 mm for the NME. Greater acid phosphatase and phytase activities were observed in the ME grown under different levels of Po relative to the NME. This indicated fine root morphology, enhanced acid phosphatase and phytase activities might be adaptations to high Po media. Results from this study establish that the ME of P. hydropiper is capable of assimilating P from Po media and is a potential material for phytoremediation of polluted area with high Po. PMID:25699065

  6. Supplementation of prepartum dairy cows with ?-carotene.

    PubMed

    Oliveira, R C; Guerreiro, B M; Morais Junior, N N; Araujo, R L; Pereira, R A N; Pereira, M N

    2015-09-01

    The prepartum supplementation of dairy cows with ?-carotene was evaluated. Cows were blocked by parity and expected calving date and assigned to a treatment: ?-carotene (1.2 g/cow per d) or control (no supplementation). The same total mixed ration batch was offered to all cows, and ?-carotene was top dressed to individual cows once per day. The data set contained 283 Holsteins that received a treatment for >14 d (29.1±6.9 d). Frequency distributions were analyzed with the GENMOD procedure of SAS using logistic regression for binomial data. Continuous variables were analyzed with the MIXED procedure of SAS. Within parity, nonparametric estimates of the survivor function for reproductive variables were computed using the product-limit method of the Kaplan-Meier method with the LIFETEST procedure of SAS. Plasma ?-carotene concentration before supplementation was similar between supplemented and nonsupplemented cows (2.99µg/mL) and peaked at 3.26±0.175µg/mL on d -15±2.4 precalving for supplemented cows (2.62±0.168µg/mL for control). Colostrum density, milk yield, and milk composition were similar between treatments. ?-Carotene tended to increase milk protein content from 2.90 to 2.96% and to decrease the proportion of primiparous cows with a milk fat to protein ratio >1.5 from 22.6 to 6.4%. The proportion of primiparous and multiparous cows with difficult calving, metritis, progesterone >1 ng/mL at 21 d and at 42 d in lactation, % conception at first service, and % pregnancy at 90 and 150 d in lactation were similar between treatments. A trend for decreased incidence of somatic cell count >200,000 cells/mL was present in multiparous cows supplemented with ?-carotene (38.9% vs. 28.1%). ?-Carotene was associated with a reduction in the proportion of multiparous cows with retained placenta 12 h postpartum from 29.9 to 21.7%; time of placenta release was 392 min (340 to 440) for ?-carotene and 490 min (395 to 540) for control (median and 95% confidence interval). For primiparous cows, placenta release was not affected by ?-carotene (incidence was 15.4%). The intervals from calving to first estrus, to first service, and to conception were not affected by ?-carotene supplementation in either parity. However, independent of treatment, cows with improved reproductive efficiency had increased postpartum ?-carotene concentration in plasma. The prepartum supplementation of ?-carotene increased plasma concentration around calving. No response in milk yield or reproductive performance was detected. Beta-carotene supplementation was associated with a lower incidence of retained placenta in multiparous cows. PMID:26188566

  7. Genome-Wide Scans for Candidate Genes Involved in the Aquatic Adaptation of Dolphins

    PubMed Central

    Liu, He-Qun; Irwin, David M.; Shen, Yong-Yi; Zhang, Ya-Ping

    2013-01-01

    Since their divergence from the terrestrial artiodactyls, cetaceans have fully adapted to an aquatic lifestyle, which represents one of the most dramatic transformations in mammalian evolutionary history. Numerous morphological and physiological characters of cetaceans have been acquired in response to this drastic habitat transition, such as thickened blubber, echolocation, and ability to hold their breath for a long period of time. However, knowledge about the molecular basis underlying these adaptations is still limited. The sequence of the genome of Tursiops truncates provides an opportunity for a comparative genomic analyses to examine the molecular adaptation of this species. Here, we constructed 11,838 high-quality orthologous gene alignments culled from the dolphin and four other terrestrial mammalian genomes and screened for positive selection occurring in the dolphin lineage. In total, 368 (3.1%) of the genes were identified as having undergone positive selection by the branch-site model. Functional characterization of these genes showed that they are significantly enriched in the categories of lipid transport and localization, ATPase activity, sense perception of sound, and muscle contraction, areas that are potentially related to cetacean adaptations. In contrast, we did not find a similar pattern in the cow, a closely related species. We resequenced some of the positively selected sites (PSSs), within the positively selected genes, and showed that most of our identified PSSs (50/52) could be replicated. The results from this study should have important implications for our understanding of cetacean evolution and their adaptations to the aquatic environment. PMID:23246795

  8. Physiological and performance adaptations to an in-season soccer camp in the heat: associations with heart rate and heart rate variability.

    PubMed

    Buchheit, M; Voss, S C; Nybo, L; Mohr, M; Racinais, S

    2011-12-01

    The aim of the present study was to examine the associations between adaptive responses to an in-season soccer training camp in the heat and changes in submaximal exercising heart rate (HRex, 5-min run at 9 ?km/h), postexercise HR recovery (HRR) and HR variability (HRV). Fifteen well-trained but non-heat-acclimatized male adult players performed a training week in Qatar (34.6?±?1.9°C wet bulb globe temperature). HRex, HRR, HRV (i.e. the standard deviation of instantaneous beat-to-beat R-R interval variability measured from Poincaré plots SD1, a vagal-related index), creatine kinase (CK) activity, plasma volume (PV) changes, and post-5-min run rate of perceived exertion (RPE) were collected at six occasions in temperate environmental conditions (22°C). Players also performed the yo-yo intermittent recovery test level 1 (Yo-Yo IR1) in the same environmental conditions (22°C), both at the beginning and at the end of the training week. Throughout the intervention, HRex and HRV showed decreasing (P?

  9. 33 CFR 157.124 - COW tank washing machines.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false COW tank washing machines. 157....124 COW tank washing machines. (a) COW machines must be permanently mounted in each cargo tank. (b) The COW machines in each tank must have sufficient nozzles with the proper diameter, working...

  10. 33 CFR 157.124 - COW tank washing machines.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false COW tank washing machines. 157....124 COW tank washing machines. (a) COW machines must be permanently mounted in each cargo tank. (b) The COW machines in each tank must have sufficient nozzles with the proper diameter, working...

  11. 33 CFR 157.124 - COW tank washing machines.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false COW tank washing machines. 157....124 COW tank washing machines. (a) COW machines must be permanently mounted in each cargo tank. (b) The COW machines in each tank must have sufficient nozzles with the proper diameter, working...

  12. 33 CFR 157.124 - COW tank washing machines.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false COW tank washing machines. 157....124 COW tank washing machines. (a) COW machines must be permanently mounted in each cargo tank. (b) The COW machines in each tank must have sufficient nozzles with the proper diameter, working...

  13. 33 CFR 157.124 - COW tank washing machines.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false COW tank washing machines. 157....124 COW tank washing machines. (a) COW machines must be permanently mounted in each cargo tank. (b) The COW machines in each tank must have sufficient nozzles with the proper diameter, working...

  14. Lecture 14: Adaptation Adaptation

    E-print Network

    Lecture 14: Adaptation · Adaptation ­ Design, Observations, Experiments, Comparisons · Are traits adaptive? · Are differences among populations or species adaptive? Adaptation · A trait that ­ increases of N.S. 1. Is a specific phenotypic trait adaptive? (Shaped by N.S.?) Adaptation: 2 Questions Mirror

  15. Regulatory physiology discipline science plan

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The focus of the Regulatory Physiology discipline of the Space Physiology and Countermeasures Program is twofold. First, to determine and study how microgravity and associated factors of space flight affect the regulatory mechanisms by which humans adapt and achieve homeostasis and thereby regulate their ability to respond to internal and external signals; and, second, to study selected physiological systems that have been demonstrated to be influenced by gravity. The Regulatory Physiology discipline, as defined here, is composed of seven subdisciplines: (1) Circadian Rhythms, (2) Endocrinology, (3) Fluid and Electrolyte Regulation, (4) Hematology, (5) Immunology, (6) Metabolism and Nutrition, and (7) Temperature Regulation. The purpose of this Discipline Science Plan is to provide a conceptual strategy for NASA's Life Sciences Division research and development activities in the area of regulatory physiology. It covers the research areas critical to NASA's programmatic requirements for the Extended-Duration Orbiter, Space Station Freedom, and exploration mission science activities. These science activities include ground-based and flight; basic, applied, and operational; and animal and human research and development. This document summarizes the current status of the program, outlines available knowledge, establishes goals and objectives, identifies science priorities, and defines critical questions in regulatory physiology. It contains a general plan that will be used by both NASA Headquarters Program Offices and the field centers to review and plan basic, applied, and operational intramural and extramural research and development activities in this area.

  16. Innate and adaptive immune responses to in utero infection with bovine viral diarrhea virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infection of pregnant cows with noncytopathic (ncp) BVDV induces rapid innate and adaptive immune responses resulting in clearance of the virus in less than 3 weeks. Seven to 14 days after inoculation of the cow, ncpBVDV crosses the placenta and induces a fetal viremia. Establishment of persistent ...

  17. Effect of a phase I Coxiella burnetii inactivated vaccine on body temperature and milk yield in dairy cows.

    PubMed

    Schulze, L S-Ch; Borchardt, S; Ouellet, V; Heuwieser, W

    2016-01-01

    Q fever is a zoonotic disease caused by Coxiella burnetii. The pathogen is prevalent in ruminants (goats, sheep, cows), which are the main sources of human infection. In the cattle industry around the world, animal (15 to 20%) and herd (38 to 72%) level prevalences of C. burnetii are high. Vaccination of ruminants against Q fever is considered important to prevent spreading of the disease and risk of infection in humans. However, published information on side effects of the Q fever vaccination under field conditions is limited for cows. The objective of this study was to investigate the effect of the phase I C. burnetii inactivated vaccine Coxevac on body temperature and milk yield in dairy cows. In 2 experiments, a total of 508 cows were randomly divided into 2 groups to determine the effect of first vaccination on body temperature and milk yield. The C. burnetii serostatus of all cows was tested before vaccination with an indirect ELISA. The first experiment took place in the teaching and research barn of the Clinic of Animal Reproduction at the Freie Universität Berlin. Temperature was measured vaginally in 10 cows in a crossover design. The second experiment was conducted on a commercial dairy farm. Milk yield of 498 cows was measured 1 wk before and 1 wk after vaccination. In a subset of 41 cows, temperature was measured rectally. In both experiments, body temperature increased significantly after vaccination (1.0±0.9°C and 0.7±0.8°C). A significant difference was also found in body temperature between vaccinated and control cows. Thirty percent of the vaccinated animals in experiment 1 showed reversible swelling at the injection site as a reaction to the vaccination. The results indicate that vaccination against Q fever causes a transient increase of body temperature that peaks in the first 12 to 24h and declines after that. In experiment 2, vaccinated cows (26.8±0.39kg/d) produced significantly less milk than did control cows (28.2±0.44kg/d) 7d after first vaccination. The cumulative milk loss after first vaccination was influenced by an interaction between C. burnetii serostatus and average milk yield 7d before first vaccination. This was considered as part of the physiological immune response. Three out of 10 vaccinated animals in experiment 1 showed painful swelling of the skin at the injection site, which had a maximum size of 14.0×14.0×1.1cm. In conclusion, a transient increase of body temperature and a decrease in milk yield is prevalent after Coxevac vaccination. PMID:26547657

  18. Respiratory heat loss of Holstein cows in a tropical environment

    NASA Astrophysics Data System (ADS)

    Campos Maia, Alex Sandro; Gomes Dasilva, Roberto; Battiston Loureiro, Cintia Maria

    2005-05-01

    In order to develop statistical models to predict respiratory heat loss in dairy cattle using simple physiological and environmental measurements, 15 Holstein cows were observed under field conditions in a tropical environment, in which the air temperature reached up to 40°C. The measurements of latent and sensible heat loss from the respiratory tract of the animals were made by using a respiratory mask. The results showed that under air temperatures between 10 and 35°C sensible heat loss by convection decreased from 8.24 to 1.09 W m-2, while the latent heat loss by evaporation increased from 1.03 to 56.51 W m-2. The evaporation increased together with the air temperature in almost a linear fashion until 20°C, but it became increasingly high as the air temperature rose above 25°C. Convection was a mechanism of minor importance for respiratory heat transfer. In contrast, respiratory evaporation was an effective means of thermoregulation for Holsteins in a hot environment. Mathematical models were developed to predict both the sensible and latent heat loss from the respiratory tract in Holstein cows under field conditions, based on measurements of the ambient temperature, and other models were developed to predict respiration rate, tidal volume, mass flow rate and expired air temperature as functions of the ambient temperature and other variables.

  19. Whole cow's milk in early life.

    PubMed

    Thorsdottir, Inga; Thorisdottir, Asa V

    2011-01-01

    Cow's milk is a major food for young children. Whole cow's milk is known to be detrimental to infants, mainly due to its low iron content. The negative association with iron status led to recommending the introduction of formula feeding in infancy during the weaning period or when breastfeeding ceased. More recently, the literature suggests that consuming whole cow's milk in infancy has unfortunate effects on growth, especially weight acceleration and development of overweight in childhood. These issues are discussed in the following chapter. Other suggested reasons for the avoidance of whole cow's milk in infancy are touched upon, such as milk protein allergy and high renal solute load. The hypothesis about early cow's milk introduction in the pathology of certain diseases, mainly through the peptide ?-casomorphin-7, is briefly reviewed, showing that there is no clear evidence for the suggested associations. The chapter gives a recent example of introducing formula at 6 months of age instead of whole cow's milk in infants' diet in Iceland. Several aspects of consuming whole cow's milk in infancy can be found in recent reviews. PMID:21335988

  20. Gravitational adaptation of animals

    NASA Technical Reports Server (NTRS)

    Smith, A. H.; Burton, R. R.

    1982-01-01

    The effect of gravitational adaptation is studied in a group of five Leghorn cocks which had become physiologically adapted to 2 G after 162 days of centrifugation. After this period of adaptation, they are periodically exposed to a 2 G field, accompanied by five previously unexposed hatch-mates, and the degree of retained acceleration adaptation is estimated from the decrease in lymphocyte frequency after 24 hr at 2 G. Results show that the previously adapted birds exhibit an 84% greater lymphopenia than the unexposed birds, and that the lymphocyte frequency does not decrease to a level below that found at the end of 162 days at 2 G. In addition, the capacity for adaptation to chronic acceleration is found to be highly heritable. An acceleration tolerant strain of birds shows lesser mortality during chronic acceleration, particularly in intermediate fields, although the result of acceleration selection is largely quantitative (a greater number of survivors) rather than qualitative (behavioral or physiological changes).

  1. Adverse effects of cow's milk in infants.

    PubMed

    Ziegler, Ekhard E

    2007-01-01

    The feeding of cow's milk has adverse effects on iron nutrition in infants and young children. Several different mechanisms have been identified that may act synergistically. Probably most important is the low iron content of cow's milk. It makes it difficult for the infant to obtain the amounts of iron needed for growth. A second mechanism is the occult intestinal blood loss, which occurs in about 40% of normal infants during feeding of cow's milk. Loss of iron in the form of blood diminishes with age and ceases after 1 year of age. A third factor is calcium and casein provided by cow's milk in high amounts. Calcium and casein both inhibit the absorption of dietary nonheme iron. Infants fed cow's milk receive much more protein and minerals than they need. The excess has to be excreted in the urine. The high renal solute load leads to higher urine concentration during the feeding of cow's milk than during the feeding of breast milk or formula. When fluid intakes are low and/or when extrarenal water losses are high, the renal concentrating ability of infants may be insufficient for maintaining water balance in the face of high water use for excretion of the high renal solute. The resulting negative water balance, if prolonged, can lead to serious dehydration. There is strong epidemiological evidence that the feeding of cow's milk or formulas with similarly high potential renal solute load places infants at an increased risk of serious dehydration. The feeding of cow's milk to infants is undesirable because of cow's milk's propensity to lead to iron deficiency and because it unduly increases the risk of severe dehydration. PMID:17664905

  2. A cow-level association of ruminal pH on body condition score, serum beta-hydroxybutyrate and postpartum disorders in Thai dairy cattle.

    PubMed

    Chaidate, Inchaisri; Somchai, Chanpongsang; Jos, Noordhuizen; Henk, Hogeveen

    2014-09-01

    Subacute ruminal acidosis in dairy cows occurs when ruminal pH is below about 5.5. However, the exact threshold level of ruminal pH affecting cow health is still in debate. This investigation was carried out in 505 cows within 31 farms. The postpartum disorders, including dystocia, retained placenta, anestrus, cystic ovary, metritis, clinical mastitis and lameness, were analyzed. Ruminal pH, serum beta-hydroxy butyrate (SBHB), serum urea nitrogen and body condition score (BCS) were measured once during the 3 to 6 weeks postpartum, while BCS was determined once more at 1 week before calving. Ruminal pH was determined by ruminocentesis technique. The ruminal pH was evaluated to study the association with BCS, SBHB and postpartum disorders using linear regression in a generalized linear mixed model with farm as a random effect. The results show that low ruminal pH was associated with dystocia, metritis and lameness. Moreover, a low ruminal pH can be found in cows with a high loss of BCS after calving and also in cows with low SBHB postpartum. These findings confirmed the feasibility of the ruminocentesis technique and the association of low ruminal pH on various postpartum disorders at the individual cow level. However, the consequences of low ruminal pH on dairy cow health still needs more exploration for a better understanding of the physiological mechanisms. PMID:24961478

  3. Swimming physiology.

    PubMed

    Holmér, I

    1992-05-01

    Swimming takes place in a medium, that presents different gravitational and resistive forces, respiratory conditions and thermal stress compared to air. The energy cost of propulsion in swimming is high, but a considerable reduction occurs at a given velocity as result of regular swim training. In medley swimmers the energy cost is lowest for front crawl, followed by backstroke, butterfly and breast-stroke. Cardiac output is probably not limiting for performance since swimmers easily achieve higher values during running. Maximal heart rate, however, is lowered by approx. 10 beats/min during swimming compared to running. Most likely active muscle mass is smaller and rate of power production lesser in swimming. Local factors, such as peripheral circulation, capillary density, perfusion pressure and metabolic capacity of active muscles, are important determinants of the power production capacity and emphasize the role of swim specific training movements. Improved swimming technique and efficiency are likely to explain much of the continuous progress in performance. Rational principles based on improved understanding of the biomechanics and physiology of swimming should be guidelines for swimmers and coaches in their efforts to explore the limits of human performance. PMID:1642724

  4. Effects of feeding birdsfoot trefoil hay on neutral detergent fiber digestion, nitrogen utilization efficiency, and lactational performance by dairy cows.

    PubMed

    Christensen, R G; Yang, S Y; Eun, J-S; Young, A J; Hall, J O; MacAdam, J W

    2015-11-01

    This experiment was conducted to determine effects of feeding birdsfoot trefoil hay-based diets in comparison with an alfalfa hay-based diet on N utilization efficiency, ruminal fermentation, and lactational performance by mid-lactation dairy cows. Nine multiparous lactating Holstein cows (131±22.6 d in milk), 3 of which were rumen fistulated, were fed 3 experimental diets in a replicated 3×3 Latin square design with 3 periods of 14 d of adaptation and 7 d of data and sample collection. Within squares, cows were randomly assigned to diets as follows: alfalfa hay-based diet (AHT), alfalfa and birdsfoot trefoil hay-based diet (ABT), and birdsfoot trefoil hay-based diet (BT). Intakes of dry matter and crude protein were similar across treatments, whereas ABT and BT diets resulted in decreased fiber intake compared with AHT. Feeding BT tended to increase neutral detergent fiber digestibility compared with AHT and ABT. Milk yield tended to increase for cows consuming ABT or BT diets. Milk true protein concentration and yield were greater for cows consuming ABT relative to those fed AHT. Concentration of total volatile fatty acids tended to increase by cows fed BT compared with those fed AHT and ABT. Feeding birdsfoot trefoil hay in a total mixed ration resulted in a tendency to decrease acetate proportion, but it tended to increase propionate proportion, leading to a tendency to decrease acetate-to-propionate ratio. Whereas concentration of ammonia-N was similar across treatments, cows offered BT exhibited greater microbial protein yield relative to those fed AHT and ABT. Cows offered birdsfoot trefoil hay diets secreted more milk N than AHT, resulting in improved N utilization efficiency for milk N. The positive effects due to feeding birdsfoot trefoil hay were attributed to enhanced neutral detergent fiber digestion, and thus it could replace alfalfa hay in high-forage dairy diets while improving N utilization efficiencies and maintaining lactational performance compared with alfalfa hay. PMID:26364095

  5. Biomedical Physiology and Kinesiology

    E-print Network

    Chauve, Cedric

    .ca/science/undergrad/advising Biomedical Physiology and Kinesiology This department links the study of physiology, anatomy and movement degree. All provide a background in physiology and anatomy. Biomedical Physiology provides a strongSCIENCE Biomedical Physiology and Kinesiology SFU.CA/ SCIENCE #12;Further Information Student info

  6. 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. PMID:20363020

  7. A review of research on genetic variation in physiological characteristics related to performance in dairy cattle.

    PubMed

    Kiddy, C A

    1979-05-01

    Genetic influence on physiological characteristics ranges from single gene effects on amino acid substitutions in alternative forms of proteins to quantitative genetic effects on the amounts of enzymes and hormones. The number of loci involved in the control of quantitative variation in physiologically important substances is not known. A number of marker genes that affect blood antigens, serum and milk proteins, and enzymes have been identified in dairy cattle. However, relatively little is known about genetic effects on quantitative physiological traits in dairy cattle. Much more is known about the genetic control of hormones in laboratory animals. About 25% of the variation in milk production of dairy cows results from genetic differences. We need more studies of genetic influences on the various physiological and biochemical processes involved in the secretion of milk to reveal the mechanisms by which genetics influences the quantity and quality of milk produced by individual cows. PMID:379062

  8. Effects of high concentrations of dietary crude glycerin on dairy cow productivity and milk quality.

    PubMed

    Ezequiel, J M B; Sancanari, J B D; Machado Neto, O R; da Silva, Z F; Almeida, M T C; Silva, D A V; van Cleef, F O S; van Cleef, E H C B

    2015-11-01

    An increasing worldwide interest in alternative fuel sources and in a more diversified energy matrix has provided incentives for the biodiesel industry, generating large amounts of the by-product crude glycerin, a potential alternative feed for dairy cows. A replicated 3×3 Latin square study was conducted to evaluate the effects of high concentrations of crude glycerin on dry matter intake, milk yield and composition, milk fatty acid profile, and blood metabolites of medium-yield cows. Ruminally cannulated Holstein cows (n=6; 587±39kg of body weight; 114±29 d in milk; and 20±1.5kg/d milk yield) were used in the study. The experimental period included 2 wk for adaptation and 1 wk for data collection. Cows were fed diets containing 0 (control), 15, or 30% crude glycerin (83% glycerol). Cows were milked, milk weights were recorded twice daily, and milk samples were collected for milk quality analyses at d 18 and 19 in each experimental period. Feeding cows with crude glycerin linearly decreased dry-matter intake, the 3.5% fat-corrected milk, and the solid-corrected milk yield. Hepatic enzymes were not affected by dietary treatments, except gamma-glutamyl transferase, which was decreased with the 15% crude glycerin diet. Serum glucose and albumin showed quadratic effect with increasing inclusion of crude glycerin. Plasma cholesterol as well as total protein linearly decreased with increasing inclusion of crude glycerin. Milk fat concentration and yield showed a quadratic effect of treatments. Solid yield decreased linearly with increasing inclusion of crude glycerin. Odd-chain fatty acids and conjugated linoleic acid in milk fat linearly increased with addition of crude glycerin in the diets. Together, these results suggest that crude glycerin has potential to replace corn; however, feeding diets in which corn is replaced with crude glycerin at 30% of dietary DM greatly reduces animal performance. PMID:26298757

  9. Cow-Calf Enterprise Standardized Performance Analysis 

    E-print Network

    McCorkle, Dean; Bevers, Stan

    2009-03-02

    SPA is a tool for determining the production and financial performance of an individual cow-calf enterprise. It allows producers to compare production systems, identify areas that need to be changed and measure progress toward meeting business...

  10. Effects of different feeding time and frequency on metabolic conditions and milk production in heat-stressed dairy cows

    NASA Astrophysics Data System (ADS)

    Calamari, L.; Petrera, F.; Stefanini, L.; Abeni, F.

    2013-09-01

    The aim of this paper was to evaluate the effects of three different feeding management (FM) schedules on physiological markers of heat stress (HS), metabolic conditions, milk yield and quality during the hot season in dairy cows. The study involved 27 mid-lactating cows, subdivided in three homogeneous groups differing in feeding time and frequency: total mixed ration (TMR) delivered once daily in the morning (M); twice daily, half in the morning and half in the evening (ME); once daily in the evening (E). During the trial, blood samples were collected in the morning (a.m.) and in the evening (p.m.), breathing rate (BR), rectal temperature (RT), and milk yield were recorded and individual milk samples were collected. Microclimate data indicated that cows were subjected to mild-moderate HS. During the hotter days, cows receiving M treatment showed higher values of RT (38.97 °C vs 38.68 °C and 38.62 °C, in ME and E) and BR (71.44 vs 66.52 and 65.26 breaths min-1, in ME and E), a.m. plasma glucose was lower in M (3.69 vs 3.83 and 3.83 mmol L-1, in ME and E) and a.m. plasma urea was lower in E (4.82 vs 5.48 and 5.35 mmol L-1, in M and ME). Milk yield was unaffected by FM, as well as milk composition and cheese-making properties. Only milk protein content and yield were higher in M (3.42 vs 3.36 and 3.27 g 100 mL-1; and 1.11 vs 1.08 and 1.02 kg day-1, for ME and E). Our results on cow physiology indicate that M seems a less suitable FM to match cow welfare during the summer season.

  11. Effects of different feeding time and frequency on metabolic conditions and milk production in heat-stressed dairy cows.

    PubMed

    Calamari, L; Petrera, F; Stefanini, L; Abeni, F

    2013-09-01

    The aim of this paper was to evaluate the effects of three different feeding management (FM) schedules on physiological markers of heat stress (HS), metabolic conditions, milk yield and quality during the hot season in dairy cows. The study involved 27 mid-lactating cows, subdivided in three homogeneous groups differing in feeding time and frequency: total mixed ration (TMR) delivered once daily in the morning (M); twice daily, half in the morning and half in the evening (ME); once daily in the evening (E). During the trial, blood samples were collected in the morning (a.m.) and in the evening (p.m.), breathing rate (BR), rectal temperature (RT), and milk yield were recorded and individual milk samples were collected. Microclimate data indicated that cows were subjected to mild-moderate HS. During the hotter days, cows receiving M treatment showed higher values of RT (38.97 °C vs 38.68 °C and 38.62 °C, in ME and E) and BR (71.44 vs 66.52 and 65.26 breaths min?¹, in ME and E), a.m. plasma glucose was lower in M (3.69 vs 3.83 and 3.83 mmol?L?¹, in ME and E) and a.m. plasma urea was lower in E (4.82 vs 5.48 and 5.35 mmol?L?¹, in M and ME). Milk yield was unaffected by FM, as well as milk composition and cheese-making properties. Only milk protein content and yield were higher in M (3.42 vs 3.36 and 3.27 g 100 mL?¹; and 1.11 vs 1.08 and 1.02 kg day?¹, for ME and E). Our results on cow physiology indicate that M seems a less suitable FM to match cow welfare during the summer season. PMID:23161272

  12. Heart Rate and Heart Rate Variability in Dairy Cows with Different Temperament and Behavioural Reactivity to Humans

    PubMed Central

    T?zsér, János; Szenci, Ottó; Póti, Péter; Pajor, Ferenc

    2015-01-01

    From the 1990s, extensive research was started on the physiological aspects of individual traits in animals. Previous research has established two extreme (proactive and reactive) coping styles in several animal species, but the means of reactivity with the autonomic nervous system (ANS) activity has not yet been investigated in cattle. The aim of this study was the characterization of cardiac autonomic activity under different conditions in cows with different individual characteristics. For this purpose, we investigated heart rate and ANS-related heart rate variability (HRV) parameters of dairy cows (N = 282) on smaller- and larger-scale farms grouped by (1) temperament and (2) behavioural reactivity to humans (BRH). Animals with high BRH scores were defined as impulsive, while animals with low BRH scores were defined as reserved. Cardiac parameters were calculated for undisturbed lying (baseline) and for milking bouts, the latter with the presence of an unfamiliar person (stressful situation). Sympathetic tone was higher, while vagal activity was lower in temperamental cows than in calm animals during rest both on smaller- and larger-scale farms. During milking, HRV parameters were indicative of a higher sympathetic and a lower vagal activity of temperamental cows as compared to calm ones in farms of both sizes. Basal heart rate did not differ between BRH groups either on smaller- or larger-scale farms. Differences between basal ANS activity of impulsive and reserved cows reflected a higher resting vagal and lower sympathetic activity of reserved animals compared to impulsive ones both on smaller- and larger-scale farms. There was no difference either in heart rate or in HRV parameters between groups during milking neither in smaller- nor in larger-scale farms. These two groupings allowed to draw possible parallels between personality and cardiac autonomic activity during both rest and milking in dairy cows. Heart rate and HRV seem to be useful for characterisation of physiological differences related to temperament and BRH. PMID:26291979

  13. Response of the Cholesterol Metabolism to a Negative Energy Balance in Dairy Cows Depends on the Lactational Stage

    PubMed Central

    Albrecht, Christiane; Bruckmaier, Rupert M.

    2015-01-01

    The response of cholesterol metabolism to a negative energy balance (NEB) induced by feed restriction for 3 weeks starting at 100 days in milk (DIM) compared to the physiologically occurring NEB in week 1 postpartum (p.p.) was investigated in 50 dairy cows (25 control (CON) and 25 feed-restricted (RES)). Blood samples, liver biopsies and milk samples were taken in week 1 p.p., and in weeks 0 and 3 of feed restriction. Plasma concentrations of total cholesterol (C), phospholipids (PL), triglycerides (TAG), very low density lipoprotein-cholesterol (VLDL-C) and low density lipoprotein-cholesterol (LDL-C) increased in RES cows from week 0 to 3 during feed restriction and were higher in week 3 compared to CON cows. In contrast, during the physiologically occurring NEB in week 1 p.p., C, PL, TAG and lipoprotein concentrations were at a minimum. Plasma phospholipid transfer protein (PLTP) and lecithin:cholesterol acyltransferase (LCAT) activities did not differ between week 0 and 3 for both groups, whereas during NEB in week 1 p.p. PLTP activity was increased and LCAT activity was decreased. Milk C concentration was not affected by feed restriction in both groups, whereas milk C mass was decreased in week 3 for RES cows. In comparison, C concentration and mass in milk were elevated in week 1 p.p. Hepatic mRNA abundance of sterol regulatory element-binding factor-2 (SREBF-2), 3-hydroxy-3-methylglutaryl-coenzyme A synthase 1 (HMGCS1), 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), and ATP-binding cassette transporter (ABCA1) were similar in CON and RES cows during feed restriction, but were upregulated during NEB in week 1 p.p. compared to the non-lactating stage without a NEB. In conclusion, cholesterol metabolism in dairy cows is affected by nutrient and energy deficiency depending on the stage of lactation. PMID:26034989

  14. Development of a physiologically based pharmacokinetic model for flunixin in cattle (Bos taurus)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Violative residues of flunixin in tissues from bob veal calves and cull dairy cows has been attributed to noncompliance with the FDA-approved route of administration and withdrawal time, however, the effect of administration route and physiological differences among animals on tissue residue depleti...

  15. Whole cow's milk: why, what and when?

    PubMed

    Michaelsen, Kim Fleischer; Hoppe, Camilla; Lauritzen, Lotte; Molgaard, Christian

    2007-01-01

    There are differences between at what age industrialized countries recommend that cow's milk can be introduced to infants. Most countries recommend waiting until 12 months of age, but according to recommendations from some countries (e.g. Canada, Sweden and Denmark) cow's milk can be introduced from 9 or 10 months. The main reason for delaying introduction is to prevent iron deficiency as cow's milk is a poor iron source. In one study mainly milk intake above 500 ml/day caused iron deficiency. Cow's milk has a very low content of linoleic acid (LA), but a more favorable LA/alpha-linolenic ratio, which is likely to be the reason why red blood cell docosahexaenoic acid (DHA) levels seem to be more favorable in infants drinking cow's milk compared to infants drinking infant formula that is not supplemented with DHA. It has been suggested that cow's milk intake can affect the later risk of obesity, blood pressure and linear growth, but the evidence is not convincing. There are also considerable differences in recommendations on at what age cow's milk with reduced fat intake can be introduced. The main consideration is that low-fat milk might limit energy intake and thereby growth, but the potential effects on development of early obesity should also be considered. Recommendations about the age for introduction of cow's milk should take into consideration traditions and feeding patterns in the population, especially the intake of iron and long-chain polyunsaturated fatty acids and should also give recommendations on the volume of milk. PMID:17664906

  16. A model for adaptive livestock management on semi-arid rangelands in Texas 

    E-print Network

    Dube, Sikhalazo

    2006-08-16

    A stochastic, compartmental Model for Adaptive Livestock Management (MALM) was developed for cow-calf enterprise for Rolling Plains of Texas from an existing model, Simple Ecological Sustainability Simulator (SESS). The ...

  17. Mastitis in post-partum dairy cows.

    PubMed

    Pyörälä, S

    2008-07-01

    Transition from the dry period to lactation is a high risk period for the modern dairy cow. The biggest challenge at that time is mastitis. Environmental bacteria are the most problematic pathogens around parturition. Coliforms are able to cause severe infections in multiparous cows, and heifers are likely to be infected with coagulase-negative staphylococci. During the periparturient period, hormonal and other factors make the dairy cows more or less immunocompromised. A successful mastitis control programme is focused on the management of dry and calving cows and heifers. Clean and comfortable environment, proper feeding and adequate supplementation of the diet with vitamins and trace elements are essential for maintaining good udder health. Strategies which would enhance closure of the teat canal in the beginning of the dry period and would protect teat end from bacteria until the keratin plug has formed decrease the risk for mastitis after calving. Dry cow therapy has been used with considerable success. Yet, a selective approach could be recommended rather than blanket therapy. Non-antibiotic approaches can be useful tools to prevent new infections during the dry period, in herds where the risk for environmental mastitis is high. Vaccination has been suggested as a means to support the immune defence of the dairy cow around parturition. In some countries, implementation of Escherichia coli core antigen vaccine has reduced the incidence of severe coliform mastitis after calving. PMID:18638132

  18. Increasing glucogenic precursors in range supplements improves reproductive efficiency and profitability in young postpartum range cows in years 2000 to 2007

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reproductive efficiency 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 increasing in glucog...

  19. Effect of ovulatory follicle size on steroidogenic capacity and molecular markers of oocyte competence prior to GnRH-induced ovulation in non-lactating beef cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gonadotropin releasing hormone (GnRH)-induced ovulation of small dominant follicles decreased pregnancy rates and increased late embryonic/fetal mortality in beef cows. Inadequate oocyte competence, as affected by the physiological status of the dominant follicle, is a potential explanation for the...

  20. INCREASING GLUCOGENIC PRECURSORS IN RANGE SUPPLEPMENTS IMPROVES REPRODUCTIVE EFFICIENCY AND PROFITABILITY IN YOUNG POSTPARTUM RANGE COWS IN YEARS 2000 TO 2007

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reproductive efficiency 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 increasing in glucog...

  1. Chromium improves production and alters metabolism of early lactation cows in summer.

    PubMed

    Mirzaei, M; Ghorbani, G R; Khorvash, M; Rahmani, H R; Nikkhah, A

    2011-02-01

    Metabolic demands of early lactation introduce enormous challenges to dairy cows when coincided with environmental stresses. The objective of this study was to determine effects of a chromium (Cr) supplement on feed intake and blood indicators of nutrient metabolism in early lactation cows in summer. Fifteen Holstein cows at 38±6 days in milk were grouped based on parity and randomly assigned to three supplemental doses of 0, 0.05 and 0.10 mg Cr/kg of BW(0.75) . Cows received a basal mixed ration with a forage to concentrate ratio of 57.7:42.3, twice daily at 09:00 and 16:00 h for 9 weeks. The first 2 weeks were for adaptation, and the following 7 weeks were for weekly sampling and data collection. The Cr supplement (a Cr-methionine product with 10% Cr and 90% Met from a compound containing one atom of Cr and three molecules of Met) was mixed with 100 g of ground corn and top dressed with the morning feed. The average ambient temperature-humidity index was 77.7 units during the study. Dry matter intake increased from 21.8 to 24.2 and 23.7 kg/day when 0.05 and 0.10 mg Cr/kg BW(0.75) was provided respectively. Milk output of energy, fat, protein and total solids increased by providing Cr at 0.05 mg but not 0.10 mg/kg BW(0.75) . Both doses of Cr increased milk protein content, but the higher Cr dose reduced feed efficiency compared with control. While rectal temperature and body condition score were unaffected, cows receiving 0.05 mg and not 0.10 mg Cr/kg BW(0.75) tended to have greater respiration rate than control cows. Blood insulin and non-esterified fatty acids concentrations and the insulin to glucagon ratio decreased, and serum albumin increased when cows received 0.05 mg of Cr/kg BW(0.75) . Blood glucose, glucagon, insulin-like growth factor-1, total protein, globulins, urea, BHBA, triglycerides, cholesterol, cortisol, progesterone, and high- and very low-density lipoproteins were not affected. Therefore, supplemental Cr supply at 0.05 and 0.10 mg/kg BW(0.75) improved feed intake, only at 0.05 mg/kg BW(0.75) increased milk secretion, and mainly at 0.05 mg/kg BW(0.75) altered peripheral nutrient metabolism in early lactation Holstein cows under high ambient temperatures. PMID:20579184

  2. Dry period plane of energy: Effects on glucose tolerance in transition dairy cows.

    PubMed

    Mann, S; Yepes, F A Leal; Duplessis, M; Wakshlag, J J; Overton, T R; Cummings, B P; Nydam, D V

    2016-01-01

    Overfeeding energy in the dry period can affect glucose metabolism and the energy balance of transition dairy cows with potential detrimental effects on the ability to successfully adapt to early lactation. The objectives of this study were to investigate the effect of different dry cow feeding strategies on glucose tolerance and on resting concentrations of blood glucose, glucagon, insulin, nonesterified fatty acids (NEFA), and ?-hydroxybutyrate (BHB) in the peripartum period. Cows entering second or greater lactation were enrolled at dry-off (57d before expected parturition) into 1 of 3 treatment groups following a randomized block design: cows that received a total mixed ration (TMR) formulated to meet but not exceed energy requirements during the dry period (n=28, controlled energy); cows that received a TMR supplying approximately 150% of energy requirements during the dry period (n=28, high energy); and cows that were fed the same diet as the controlled energy group for the first 28d, after which the TMR was formulated to supply approximately 125% of energy requirements until calving (n=28, intermediate energy). Intravenous glucose tolerance tests (IVGTT) with rapid administration of 0.25g of glucose/kg of body weight were performed 28 and 10d before expected parturition, as well as at 4 and 21d after calving. Area under the curve for insulin and glucose, maximal concentration and time to half-maximal concentration of insulin and glucose, and clearance rates were calculated. Insulin resistance (IR) indices were calculated from baseline samples obtained during IVGTT and Spearman rank correlations determined between IVGTT parameters and IR indices. Treatment did not affect IVGTT parameters at any of the 4 time points. Correlation between IR indices and IVGTT parameters was generally poor. Overfeeding cows energy in excess of predicted requirements by approximately 50% during the entire dry period resulted in decreased postpartum basal plasma glucose and insulin, as well as increased glucagon, BHB, and NEFA concentrations after calving compared with cows fed a controlled energy diet during the dry period. In conclusion, overfeeding energy during the entire dry period or close-up period alone did not affect glucose tolerance as assessed by IVGTT but energy uptake during the dry period was associated with changes in peripartal resting concentrations of glucose, as well as postpartum insulin, glucagon, NEFA, and BHB concentrations. PMID:26627861

  3. Persistency of methane mitigation by dietary nitrate supplementation in dairy cows.

    PubMed

    van Zijderveld, S M; Gerrits, W J J; Dijkstra, J; Newbold, J R; Hulshof, R B A; Perdok, H B

    2011-08-01

    Feeding nitrate to dairy cows may lower ruminal methane production by competing for reducing equivalents with methanogenesis. Twenty lactating Holstein-Friesian dairy cows (33.2±6.0 kg of milk/d; 104±58 d in milk at the start of the experiment) were fed a total mixed ration (corn silage-based; forage to concentrate ratio 66:34), containing either a dietary urea or a dietary nitrate source [21 g of nitrate/kg of dry matter (DM)] during 4 successive 24-d periods, to assess the methane-mitigating potential of dietary nitrate and its persistency. The study was conducted as paired comparisons in a randomized design with repeated measurements. Cows were blocked by parity, lactation stage, and milk production at the start of the experiment. A 4-wk adaptation period allowed the rumen microbes to adapt to dietary urea and nitrate. Diets were isoenergetic and isonitrogenous. Methane production, energy balance, and diet digestibility were measured in open-circuit indirect calorimetry chambers. Cows were limit-fed during measurements. Nitrate persistently decreased methane production by 16%, whether expressed in grams per day, grams per kilogram of dry matter intake (DMI), or as percentage of gross energy intake, which was sustained for the full experimental period (mean 368 vs. 310±12.5 g/d; 19.4 vs. 16.2±0.47 g/kg of DMI; 5.9 vs.4.9±0.15% of gross energy intake for urea vs. nitrate, respectively). This decrease was smaller than the stoichiometrical methane mitigation potential of nitrate (full potential=28% methane reduction). The decreased energy loss from methane resulted in an improved conversion of dietary energy intake into metabolizable energy (57.3 vs. 58.6±0.70%, urea vs. nitrate, respectively). Despite this, milk energy output or energy retention was not affected by dietary nitrate. Nitrate did not affect milk yield or apparent digestibility of crude fat, neutral detergent fiber, and starch. Milk protein content (3.21 vs. 3.05±0.058%, urea vs. nitrate respectively) but not protein yield was lower for dietary nitrate. Hydrogen production between morning and afternoon milking was measured during the last experimental period. Cows fed nitrate emitted more hydrogen. Cows fed nitrate displayed higher blood methemoglobin levels (0.5 vs. 4.0±1.07% of hemoglobin, urea vs. nitrate respectively) and lower hemoglobin levels (7.1 vs. 6.3±0.11 mmol/L, urea vs. nitrate respectively). Dietary nitrate persistently decreased methane production from lactating dairy cows fed restricted amounts of feed, but the reduction in energy losses did not improve milk production or energy balance. PMID:21787938

  4. Alteration of the Endometrial EGF Profile as a Potential Mechanism Connecting the Alterations in the Ovarian Steroid Hormone Profile to Embryonic Loss in Repeat Breeders and High-producing Cows

    PubMed Central

    KATAGIRI, Seiji; MORIYOSHI, Masaharu

    2013-01-01

    Poor reproductive efficiency is a worldwide problem that has affected the dairy industry during the last several decades. In an attempt to explain the changes in reproductive physiology caused by high milk production, a model of elevated steroid metabolism in lactating dairy cows has been proposed. A slow increase in levels and low peak levels of estradiol (E2) and progesterone (P4) characterize endocrine changes in high producing cows. Similar changes have been reported in the repeat breeder cows. The abnormal changes in E2 and P4 concentrations of these cows may cause an improper uterine environment due to disturbed expression of growth factors and cytokines in the endometrium. This review focuses on the alteration in epidermal growth factor (EGF) profile in the endometrium during the estrous cycle. The normal cow has two peaks of EGF concentrations on days 2–4 and 13–14. Low concentrations of EGF on these days distinguished both high-producing and repeat breeder cows from normal cows. Alteration of the EGF profile could be found in 70 and 40% of the repeat breeder and high-producing cows, respectively. Treatment with a high dose of estradiol benzoate and an intravaginal progesterone-releasing device restored the normal EGF profile in about 70% of the affected cows. The cows having a normal EGF profile after treatment showed a higher pregnancy rate than the cows with the altered profile. Further studies to understand the etiology of the alteration in the EGF profile are needed to develop another treatment option and preventive management for this problem. PMID:24162805

  5. Heart Rate Variability as an Indicator of Chronic Stress Caused by Lameness in Dairy Cows

    PubMed Central

    Kulcsár-Huszenicza, Margit; T?zsér, János

    2015-01-01

    Most experimental studies on animal stress physiology have focused on acute stress, while chronic stress, which is also encountered in intensive dairy cattle farming–e.g. in case of lameness–, has received little attention. We investigated heart rate (HR) and heart rate variability (HRV) as indicators of the autonomic nervous system activity and fecal glucocorticoid concentrations as the indicator of the hypothalamic–pituitary–adrenal axis activity in lame (with locomotion scores 4 and 5; n = 51) and non-lame (with locomotion scores 1 and 2; n = 52) Holstein-Friesian cows. Data recorded during the periods of undisturbed lying–representing baseline cardiac activity–were involved in the analysis. Besides linear analysis methods of the cardiac inter-beat interval (time-domain geometric, frequency domain and Poincaré analyses) non-linear HRV parameters were also evaluated. With the exception of standard deviation 1 (SD1), all HRV indices were affected by lameness. Heart rate was lower in lame cows than in non-lame ones. Vagal tone parameters were higher in lame cows than in non-lame animals, while indices of the sympathovagal balance reflected on a decreased sympathetic activity in lame cows. All geometric and non-linear HRV measures were lower in lame cows compared to non-lame ones suggesting that chronic stress influenced linear and non-linear characteristics of cardiac function. Lameness had no effect on fecal glucocorticoid concentrations. Our results demonstrate that HRV analysis is a reliable method in the assessment of chronic stress, however, it requires further studies to fully understand the elevated parasympathetic and decreased sympathetic tone in lame animals. PMID:26270563

  6. Heart Rate Variability as an Indicator of Chronic Stress Caused by Lameness in Dairy Cows.

    PubMed

    Kovács, Levente; Kézér, Fruzsina Luca; Jurkovich, Viktor; Kulcsár-Huszenicza, Margit; T?zsér, János

    2015-01-01

    Most experimental studies on animal stress physiology have focused on acute stress, while chronic stress, which is also encountered in intensive dairy cattle farming--e.g. in case of lameness--, has received little attention. We investigated heart rate (HR) and heart rate variability (HRV) as indicators of the autonomic nervous system activity and fecal glucocorticoid concentrations as the indicator of the hypothalamic-pituitary-adrenal axis activity in lame (with locomotion scores 4 and 5; n = 51) and non-lame (with locomotion scores 1 and 2; n = 52) Holstein-Friesian cows. Data recorded during the periods of undisturbed lying--representing baseline cardiac activity--were involved in the analysis. Besides linear analysis methods of the cardiac inter-beat interval (time-domain geometric, frequency domain and Poincaré analyses) non-linear HRV parameters were also evaluated. With the exception of standard deviation 1 (SD1), all HRV indices were affected by lameness. Heart rate was lower in lame cows than in non-lame ones. Vagal tone parameters were higher in lame cows than in non-lame animals, while indices of the sympathovagal balance reflected on a decreased sympathetic activity in lame cows. All geometric and non-linear HRV measures were lower in lame cows compared to non-lame ones suggesting that chronic stress influenced linear and non-linear characteristics of cardiac function. Lameness had no effect on fecal glucocorticoid concentrations. Our results demonstrate that HRV analysis is a reliable method in the assessment of chronic stress, however, it requires further studies to fully understand the elevated parasympathetic and decreased sympathetic tone in lame animals. PMID:26270563

  7. Cardiovascular physiology and diseases of amphibians.

    PubMed

    Heinz-Taheny, Kathleen M

    2009-01-01

    The class Amphibia includes three orders of amphibians: the anurans (frogs and toads), urodeles (salamanders, axolotls, and newts), and caecilians. The diversity of lifestyles across these three orders has accompanying differences in the cardiovascular anatomy and physiology allowing for adaptations to aquatic or terrestrial habitats, pulmonic or gill respiration, hibernation, and body elongation (in the caecilian). This article provides a review of amphibian cardiovascular anatomy and physiology with discussion of unique species adaptations. In addition, amphibians as cardiovascular animal models and commonly encountered natural diseases are covered. PMID:19131029

  8. Inheritance is where physiology meets evolution

    PubMed Central

    Danchin, Étienne; Pocheville, Arnaud

    2014-01-01

    Physiology and evolutionary biology have developed as two separated disciplines, a separation that mirrored the hypothesis that the physiological and evolutionary processes could be decoupled. We argue that non-genetic inheritance shatters the frontier between physiology and evolution, and leads to the coupling of physiological and evolutionary processes to a point where there exists a continuum between accommodation by phenotypic plasticity and adaptation by natural selection. This approach is also profoundly affecting the definition of the concept of phenotypic plasticity, which should now be envisaged as a multi-scale concept. We further suggest that inclusive inheritance provides a quantitative way to help bridging infra-individual (i.e. physiology) with supra-individual (i.e. evolution) approaches, in a way that should help building the long sough inclusive evolutionary synthesis. PMID:24882815

  9. [From the Scrapie syndrome of sheep and goat to the mad cow disease - the history of the discovery of prion].

    PubMed

    Liu, Rui; Weng, Yi

    2009-05-01

    Since the discovery of Scrapie Syndrome in sheep and goats in 1730, there emerged a series of diseases such as Creutzfeldt-Jakob disease, kuru disease and mad cow disease etc. In the research of kuru disease, the American scientist D. Carlteton Gajdusek found a new virus without the characteristic of DNA and RNA, which was awarded the Nobel Prize in physiology in 1976. Since then another American scientist, Stanley B. Prusiner, found a new virus-prion, taking protein as the genetic medium, which was awarded the Nobel prize in physiology and medicine in 1997. The discovery of prion is a great landmark in the research of life science, which laid a theoretical foundation for people to conquer a series of diseases such as Scrapie syndrome in sheep and goats, Creutzfeldt-Jakob disease, kuru disease and mad cow disease etc. PMID:19930927

  10. Cow Dung Ingestion and Inhalation Dependence: A Case Report

    ERIC Educational Resources Information Center

    Khairkar, Praveen; Tiple, Prashant; Bang, Govind

    2009-01-01

    Although abuse of several unusual inhalants had been documented, addiction to cow dung fumes or their ashes has not been reported in medical literature as yet. We are reporting a case of cow dung dependence in ingestion and inhalational form.

  11. The effect of calving in the summer on the hepatic transcriptome of Holstein cows during the peripartal period.

    PubMed

    Shahzad, K; Akbar, H; Vailati-Riboni, M; Basiricò, L; Morera, P; Rodriguez-Zas, S L; Nardone, A; Bernabucci, U; Loor, J J

    2015-08-01

    The liver is the main metabolic organ coordinating the adaptations that take place during the peripartal period of dairy cows. A successful transition into lactation, rather than management practices alone, depends on environmental factors such as temperature, season of parturition, and photoperiod. Therefore, we analyzed the effect of calving season on the hepatic transcriptome of dairy cows during the transition period. A total of 12 Holstein dairy cows were assigned into 2 groups based on calving season (6 cows March-April, spring; 6 cows June-July, summer, SU). The RNA was extracted from liver samples obtained at -30, 3, and 35 DIM via percutaneous biopsy and hybridized to the Agilent 44K Bovine (V2) Gene Expression Microarray (Agilent Technologies Inc., Santa Clara, CA). A quantitative PCR on 22 target genes was performed to verify and expand the analyses. A total of 4,307 differentially expressed genes were detected (false discovery rate ?0.05) in SU compared with spring. Furthermore, 73 unique differentially expressed genes were detected in SU compared with spring cows after applying a fold-change threshold ?3 and ?-3. For Kyoto Encyclopedia of Genes and Genomes pathways analysis of differentially expressed genes, we used the dynamic impact approach. Ingenuity Pathway Analysis software was used to analyze upstream transcription regulators and perform gene network analysis. Among metabolic pathways, energy metabolism from lipids, carbohydrates, and amino acids was strongly affected by calving in SU, with a reduced level of fatty acid synthesis, oxidation, re-esterification, and synthesis of lipoproteins, leading to hepatic lipidosis. Glycan-synthesis was downregulated in SU cows probably as a mechanism to counteract the progression of this lipidosis. In contrast, calving in the SU resulted in upregulation of gluconeogenesis but also greater use of glucose as an energy source. Among nonmetabolic pathways, the heat-shock response was obviously activated in SU cows but was also associated with inflammatory and intracellular stress response. Furthermore, data support a recent finding that cows experience endoplasmic reticulum stress around parturition. Transcription regulator analysis revealed how metabolic changes are related to important regulatory mechanisms, including epigenetic modification. The holistic analyses of the liver transcriptome response to calving in the summer at high environmental temperatures underscore how transition cows should be carefully managed during this period, as they experience alterations in liver energy metabolism and inflammatory state increasing susceptibility to health disorders in early postpartum. PMID:26074246

  12. Milk production and composition of mid-lactation cows consuming perennial ryegrass-and chicory-based diets.

    PubMed

    Muir, S K; Ward, G N; Jacobs, J L

    2014-02-01

    Dry matter intakes (DMI), nutrient selection, and milk production responses of dairy cows grazing 3 herbage-based diets offered at 2 allowances were measured. The 2 allowances were 20 (low) and 30 (high) kg of dry matter (DM)/cow per day and these were applied to 3 herbage types: perennial ryegrass (PRG) and chicory (CHIC+) monocultures and a mixed sward of chicory and perennial ryegrass (MIX). The CHIC+ diet was supplemented with alfalfa hay (approximately 2 kg of DM/cow per day) to maintain dietary neutral detergent fiber (NDF) concentration and all diets were supplemented with energy-based pellets (6 kg of DM/cow per day). Holstein-Friesian dairy cows averaging 136 ± 30 d in milk were allocated to 4 replicates of the 6 treatments using stratified randomization procedures. Cows were adapted to their experimental diets over a 14-d period, with measurements of DMI, milk yield, and composition conducted over the following 10 d. Herbage DMI was lowest (12.8 vs. 14.0 kg of DM/d) for CHIC+ compared with the MIX and PRG, although total forage intake (grazed herbage plus hay) was similar (14.0 to 15.0 kg of DM/d) across the 3 treatments. Milk production, milk protein, and milk fat concentrations were not different between herbage types. Grazed herbage DMI increased with increasing herbage allowance and this was associated with increased milk protein concentration (3.23 to 3.34%) and total casein production (41.7 to 43.6 mg/g). Concentrations of polyunsaturated fatty acids in milk fat, particularly linoleic acid, were increased in milk from cows offered the CHIC+ or the MIX diets, indicating potential benefits of chicory herbage on milk fatty acid concentrations. Although feeding CHIC+ or MIX did not increase milk yield, these herbage types could be used as an alternative to perennial ryegrass pasture in spring. PMID:24290818

  13. Using Body Condition Scores to Manage Range Cows and Rangeland 

    E-print Network

    Lyons, Robert K.; Machen, Richard V.

    2001-07-19

    condition scores can be used at critical times to: a71 Determine whether supplemental feed is needed a71 Identify the cows needing special attention a71 Gain insight into the causes of nutritional prob- lems Body condition scoring is an estimation... in beef cattle, see Extension publication B-1526, ?Body Condition, Nutrition and Reproduction of Beef Cows.? As an evaluation tool, body condition scoring offers several advantages over weighing cows: a71 Cow weights are affected by variations in diges...

  14. Modelling the extinction of Steller's sea cow.

    PubMed

    Turvey, S T; Risley, C L

    2006-03-22

    Steller's sea cow, a giant sirenian discovered in 1741 and extinct by 1768, is one of the few megafaunal mammal species to have died out during the historical period. The species is traditionally considered to have been exterminated by 'blitzkrieg'-style direct overharvesting for food, but it has also been proposed that its extinction resulted from a sea urchin population explosion triggered by extirpation of local sea otter populations that eliminated the shallow-water kelps on which sea cows fed. Hunting records from eighteenth century Russian expeditions to the Commander Islands, in conjunction with life-history data extrapolated from dugongs, permit modelling of sea cow extinction dynamics. Sea cows were massively and wastefully overexploited, being hunted at over seven times the sustainable limit, and suggesting that the initial Bering Island sea cow population must have been higher than suggested by previous researchers to allow the species to survive even until 1768. Environmental changes caused by sea otter declines are unlikely to have contributed to this extinction event. This indicates that megafaunal extinctions can be effected by small bands of hunters using pre-industrial technologies, and highlights the catastrophic impact of wastefulness when overexploiting resources mistakenly perceived as 'infinite'. PMID:17148336

  15. Modelling the extinction of Steller's sea cow

    PubMed Central

    Turvey, S.T; Risley, C.L

    2005-01-01

    Steller's sea cow, a giant sirenian discovered in 1741 and extinct by 1768, is one of the few megafaunal mammal species to have died out during the historical period. The species is traditionally considered to have been exterminated by ‘blitzkrieg’-style direct overharvesting for food, but it has also been proposed that its extinction resulted from a sea urchin population explosion triggered by extirpation of local sea otter populations that eliminated the shallow-water kelps on which sea cows fed. Hunting records from eighteenth century Russian expeditions to the Commander Islands, in conjunction with life-history data extrapolated from dugongs, permit modelling of sea cow extinction dynamics. Sea cows were massively and wastefully overexploited, being hunted at over seven times the sustainable limit, and suggesting that the initial Bering Island sea cow population must have been higher than suggested by previous researchers to allow the species to survive even until 1768. Environmental changes caused by sea otter declines are unlikely to have contributed to this extinction event. This indicates that megafaunal extinctions can be effected by small bands of hunters using pre-industrial technologies, and highlights the catastrophic impact of wastefulness when overexploiting resources mistakenly perceived as ‘infinite’. PMID:17148336

  16. The effect of conspecific removal on behavioral and physiological responses of dairy cattle.

    PubMed

    Walker, Jessica K; Arney, David R; Waran, Natalie K; Handel, Ian G; Phillips, Clive J C

    2015-12-01

    Adverse social and welfare implications of mixing dairy cows or separating calves from their mothers have been documented previously. Here we investigated the behavioral and physiological responses of individuals remaining after conspecifics were removed. We conducted a series of 4 experiments incorporating a range of types of different dairy cattle groupings [experiment 1 (E1), 126 outdoor lactating dairy cows; experiment 2 (E2), 120 housed lactating dairy cows; experiment 3 (E3), 18 housed dairy calves; and experiment 4 (E4), 22 housed dairy bulls] from which a subset of individuals were permanently removed (E1, n=7; E2, n=5; E3, n=9; E4, n=18). Associations between individuals were established using near-neighbor scores (based upon identities and distances between animals recorded before removal) in E1, E2, and E3. Behavioral recordings were taken for 3 to 5 d, before and after removal on a sample of cattle in all 4 experiments (E1, n=20; E2, n=20; E3, n=9; E4, n=4). In 2 experiments with relatively large groups of dairy cows, E1 and E2, the responses of cows that did and did not associate with the removed cows were compared. An increase in time that both nonassociates and associates spent eating was observed after conspecific removal in E1. In E2, this increase was restricted to cows that had not associated with the removed cows. A reduction in ruminating in remaining cattle was observed in E3 and eating in E4. Immunoglobulin A concentrations increased after separation in both E3 and E4 cattle, but did not differ significantly between associates and nonassociates in E2. Blood and milk cortisol concentrations were not affected by conspecific removal. These findings suggest that some animals had affected feeding behavior and IgA concentrations after removal of conspecifics. PMID:26454304

  17. Body Temperature Versus Microclimate Selection in Heat Stressed Dairy Cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this study is to characterize the thermoregulatory responses of unrestrained heat-stressed dairy cows within a freestall environment using fan and spray configurations for cooling cows while lying or standing. An experimental treatment sprayed individual cows lying in freestalls from ...

  18. On the Art Career Track: Behold... the Cow as Art

    ERIC Educational Resources Information Center

    Osterer, Irv

    2011-01-01

    Cows have been a favorite subject for many artists, including Canadian artist Joe Fafard. In this article, grade 11 graphic-design students do a series of exercises in their sketchbooks using the cow motif. Each exercise was designed to have students move from traditional pictures of the dairy cow to more eclectic visual solutions. Eight…

  19. 33 CFR 157.124 - COW tank washing machines.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false COW tank washing machines. 157.124 Section 157.124 Navigation...and Installation § 157.124 COW tank washing machines. (a) COW machines must be permanently mounted in each cargo...

  20. 33 CFR 157.124 - COW tank washing machines.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false COW tank washing machines. 157.124 Section 157.124 Navigation...and Installation § 157.124 COW tank washing machines. (a) COW machines must be permanently mounted in each cargo...

  1. 33 CFR 157.124 - COW tank washing machines.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false COW tank washing machines. 157.124 Section 157.124 Navigation...and Installation § 157.124 COW tank washing machines. (a) COW machines must be permanently mounted in each cargo...

  2. 33 CFR 157.124 - COW tank washing machines.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false COW tank washing machines. 157.124 Section 157.124 Navigation...and Installation § 157.124 COW tank washing machines. (a) COW machines must be permanently mounted in each cargo...

  3. 33 CFR 157.124 - COW tank washing machines.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false COW tank washing machines. 157.124 Section 157.124 Navigation...and Installation § 157.124 COW tank washing machines. (a) COW machines must be permanently mounted in each cargo...

  4. Effect of rubber flooring on cow locomotion and gene expression

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of this study was to evaluate the effect of 2 dairy cow housing systems on cow locomotion and expression of genes associated with lameness, during the dry and peri-parturient period. Cows were assigned to free-stall housing with either rubber (RUB; n=13) or concrete (CON; n=14) at the feed-f...

  5. Factors affecting fertilization and pregnancy establishment in beef cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Embryonic mortality represents the single greatest economic loss for cow/calf producers worldwide. In beef cattle, fertilization rates to a single service exceed 90%, but rarely do 65% of matings result in pregnancy establishment and birth of a live calf. The primary difference between a cow’s est...

  6. Cardiovascular physiology - Effects of microgravity

    NASA Technical Reports Server (NTRS)

    Convertino, V.; Hoffler, G. W.

    1992-01-01

    Experiments during spaceflight and its groundbase analog, bedrest, provide consistent data which demonstrate that numerous changes in cardiovascular function occur as part of the physiological adaptation process to the microgravity environment. These include elevated heart rate and venous compliance, lowered blood volume, central venous pressure and stroke volume, and attenuated autonomic reflex functions. Although most of these adaptations are not functionally apparent during microgravity exposure, they manifest themselves during the return to the gravitational challenge of earth's terrestrial environment as orthostatic hypotension and instability, a condition which could compromise safety, health and productivity. Development and application of effective and efficient countermeasures such as saline "loading," intermittent venous pooling, pharmacological treatments, and exercise have become primary emphases of the space life sciences research effort with only limited success. Successful development of countermeasures will require knowledge of the physiological mechanisms underlying cardiovascular adaptation to microgravity which can be obtained only through controlled, parallel groundbased research to complement carefully designed flight experiments. Continued research will provide benefits for both space and clinical applications as well as enhance the basic understanding of cardiovascular homeostasis in humans.

  7. Changes of Adipose Tissue Morphology and Composition during Late Pregnancy and Early Lactation in Dairy Cows

    PubMed Central

    Kenéz, Ákos; Kulcsár, Anna; Kluge, Franziska; Benbelkacem, Idir; Hansen, Kathrin; Locher, Lena; Meyer, Ulrich; Rehage, Jürgen; Dänicke, Sven; Huber, Korinna

    2015-01-01

    Dairy cows mobilize large amounts of body fat during early lactation to overcome negative energy balance which typically arises in this period. As an adaptation process, adipose tissues of cows undergo extensive remodeling during late pregnancy and early lactation. The objective of the present study was to characterize this remodeling to get a better understanding of adaptation processes in adipose tissues, affected by changing metabolic conditions including lipid mobilization and refilling as a function of energy status. This was done by determining adipocyte size in histological sections of subcutaneous and retroperitoneal adipose tissue biopsy samples collected from German Holstein cows at 42 days prepartum, and 1, 21, and 100 days postpartum. Characterization of cell size changes was extended by the analysis of DNA, triacylglycerol, and protein content per gram tissue, and ?-actin protein expression in the same samples. In both adipose tissue depots cell size was becoming smaller during the course of the study, suggesting a decrease in cellular triacylglycerol content. Results of DNA, triacylglycerol, and protein content, and ?-actin protein expression could only partially explain the observed differences in cell size. The retroperitoneal adipose tissue exhibited a greater extent of time-related differences in cell size, DNA, and protein content, suggesting greater dynamics and metabolic flexibility for this abdominal depot compared to the investigated subcutaneous depot. PMID:25978720

  8. Comparison of two treatment strategies for cows with metritis in high-risk lactating dairy cows.

    PubMed

    Armengol, Ramon; Fraile, Lorenzo

    2015-05-01

    Acute puerperal metritis (APM) and clinical metritis (CM) are uterine diseases frequently diagnosed in dairy cows. These diseases are responsible for important economic loss because of their effect not only on reproductive performance but also on milk production. The objective of this study was to assess the impact of two different treatments for metritis on dairy cows by measuring their reproductive performance in the next gestation. The end points to measure the reproductive performance included the conception rate at the first artificial insemination, the number of days at conception, and the proportion of nonpregnant cows at over 150 days after beginning milk production. The study was carried out in a high production dairy cow farm located in Lleida (northeast Spain). Recordings of 1044 parturitions of 747 Holstein cows were controlled in this farm from 2009 to 2014. Cows were diagnosed as suffering from metritis (APM or CM) if the following parameters were observed: an abnormally enlarged uterus; a fetid, watery, reddish brown uterine discharge with (APM) or without (CM) fever (>39.5 °C); and presence (APM) or absence (CM) of signs of systemic illness (decreased milk production, dullness, or other signs of toxemia) within 21 days postpartum. Afterwards, cows suffering from metritis (APM or CM) were randomly assigned and balanced to two groups: (1) animals receiving parenteral amoxicillin intramuscularly plus intrauterine infusion with oxytetracycline (P + I group) and (2) animals receiving only parenteral amoxicillin intramuscularly (P group). Furthermore, reproductive performance of cows without metritis was used as reference (control group). Metritis was diagnosed in 27.5% of the total parturitions included in the study (288 of 1044). In particular, metritis was diagnosed in 30.5% (118 of 387) and 25.9% (170 of 657) of parturitions from heifers and multiparous cows, respectively. Reproductive performance was not significantly affected by the parity, the season at the first artificial insemination, the season at conception, the bull, or the inseminator. The P + I treatment was able to significantly reduce the number of days at the first insemination and at conception when compared with the P treatment in heifers. In multiparous cows, this significant effect was only observed for days at conception. Additionally, the P + I treatment was able to significantly increase the percentage of pregnant animals at the first insemination and decrease the percentage of nonpregnant cows at greater than 150 days in milk production for both heifers and multiparous cows when compared with the P treatment. PMID:25702623

  9. The effect of gossypol in the diet of pregnant and postpartum Brahman cows on calf development and cow performance 

    E-print Network

    Willard, Scott Thomas

    1993-01-01

    To determine the effects of dietary free gossypol (FG) in prepartum and postpartum Brahman cows on calf development and cow performance, thirty-eight pregnant cows and twelve pregnant heifers were assigned to one of three treatment groups: 1) Og FG...

  10. The Effects of Gonadotrophin Releasing Hormone Administration in Early Postpartum Dairy Cows on Hormone Concentrations, Ovarian Activity and Reproductive Performance: A Review

    PubMed Central

    Leslie, K. E.

    1983-01-01

    Gonadotrophin releasing hormones have become widely used hormonal compounds in veterinary medicine, particularly with respect to bovine reproduction. The character and physiological actions of gonadotrophin releasing hormone are briefly reviewed and its clinical applications are summarized. The endocrinological research concerned with the use of gonadotrophin releasing hormone in the early postpartum period is discussed. Field trials which have been conducted to assess the effects of postpartum gonadotrophin releasing hormone administration on reproductive performance have varied widely in both design and interpretation of results. These experiments are reviewed, including the clinical trials using normal cows as well as those on cows with retained placenta. PMID:17422245

  11. Polyamines in plant physiology

    NASA Technical Reports Server (NTRS)

    Galston, A. W.; Sawhney, R. K.

    1990-01-01

    The diamine putrescine, the triamine spermidine, and the tetramine spermine are ubiquitous in plant cells, while other polyamines are of more limited occurrence. Their chemistry and pathways of biosynthesis and metabolism are well characterized. They occur in the free form as cations, but are often conjugated to small molecules like phenolic acids and also to various macromolecules. Their titer varies from approximately micromolar to more than millimolar, and depends greatly on environmental conditions, especially stress. In cereals, the activity of one of the major polyamine biosynthetic enzymes, arginine decarboxylase, is rapidly and dramatically increased by almost every studied external stress, leading to 50-fold or greater increases in putrescine titer within a few hours. The physiological significance of this increase is not yet clear, although most recent work suggests an adaptive, protective role. Polyamines produced through the action of ornithine decarboxylase, by contrast, seem essential for DNA replication and cell division. The application of exogenous polyamines produces effects on patterns of senescence and morphogenesis, suggesting but not proving a regulatory role for polyamines in these processes. The evidence for such a regulatory role is growing.

  12. Relationships of cow age and initial cow body weight with calf and cow grazing season weight changes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The primary objective in a study implemented during 1975-2001 on northern mixed-grass prairie at the High Plains Grassland Research Station (HPGRS) near Cheyenne, Wyoming, was to evaluate long-term calf and cow grazing season body weight gain responses under 14 different management practices (e.g. t...

  13. Bacterial and fungal organisms in the vagina of normal cows and cows with vaginitis 

    E-print Network

    Husted, James Ross

    2005-02-17

    Bacterial and fungal culturing was conducted on samples taken from the vaginal fornix of 106 cows, of which 42 had vaginitis and 64 had normal vaginas. The diagnosis of vaginitis and non-vaginitis samples was determined by histologic examination...

  14. Estrus-related odors in body fluids of dairy cows.

    PubMed

    Kiddy, C A; Mitchell, D S; Hawk, H W

    1984-02-01

    Six experiments were to test for estrus-associated odors in 1) swabs of the vulva and vestibule, 2) fluids from deep in the vagina, 3) naturally voided urine, 4) urine obtained from the bladder by catheter, 5) milk, and 6) blood plasma. Tests were with dogs trained to identify vaginal fluids from estrous cows. In the tests, dogs were walked along lines of seven sample bottles consisting of samples from two estrous cows, two luteal-phase cows, one vaginal swab from estrous cows used as a standard, and two blank sample bottles. Correct responses to fluids from estrous cows averaged 97, 86, 96, 97, 99, and 94% for the six fluids listed. Incorrect responses to fluids from luteal-phase cows were 2, 1, 1, 1, 1, and 8%. Responses to blank samples were usually zero. Results indicate that odors associated with estrus are spread throughout the cow's body fluid. PMID:6715632

  15. Physiological Information Database (PID)

    EPA Science Inventory

    EPA has developed a physiological information database (created using Microsoft ACCESS) intended to be used in PBPK modeling. The database contains physiological parameter values for humans from early childhood through senescence as well as similar data for laboratory animal spec...

  16. MPTrain: A Mobile, Music and Physiology-Based Personal Trainer

    E-print Network

    Toronto, University of

    monitoring the user's physiology (heart-rate in number of beats per minute) and movement (speed in number Factors Keywords Wearable Physiological Monitoring, Automatic Playlist Gen- eration, Adaptive Mobile and adults. In particular, MP3 players and heart-rate monitors [4, 16] are becoming in- creasingly pervasive

  17. Effect of pre-grazing herbage mass on dairy cow performance, grass dry matter production and output from perennial ryegrass (Lolium perenne L.) pastures.

    PubMed

    Wims, C M; Delaby, L; Boland, T M; O'Donovan, M

    2014-01-01

    A grazing study was undertaken to examine the effect of maintaining three levels of pre-grazing herbage mass (HM) on dairy cow performance, grass dry matter (DM) production and output from perennial ryegrass (Lolium perenne L.) pastures. Cows were randomly assigned to one of three pre-grazing HM treatments: 1150 - Low HM (L), 1400 - Medium HM (M) or 2000 kg DM/ha - High HM (H). Herbage accumulation under grazing was lowest (P<0.01) on the L treatment and cows grazing the L pastures required more grass silage supplementation during the grazing season (+73 kg DM/cow) to overcome pasture deficits due to lower pasture growth rates (P<0.05). Treatment did not affect daily milk production or pasture intake, although cows grazing the L pastures had to graze a greater daily area (P<0.01) and increase grazing time (P<0.05) to compensate for a lower pre-grazing HM (P<0.01). The results indicate that, while pre-grazing HM did not influence daily milk yield per cow, adapting the practise of grazing low HM (1150 kg DM/ha) pasture reduces pasture DM production and at a system level may increase the requirement for imported feed. PMID:24229787

  18. Effects of two-stage and total vs. fence-line weaning on the physiology and performance of beef calves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Calves weaned using a two-stage method where nursing is prevented between cow-calf pairs prior to separation (Stage 1) experience less weaning stress after separation (Stage 2) based on behavior and growth measures. The aim of this study was to document changes in various physiological measures of s...

  19. Annual grass as supplements for beef cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Research has shown when limit grazing cool-season annual grasses as a supplement in a complementary forage system, energy and CP supplementation are not required and hay requirements are reduced 23% for gestating beef cows. To further improve the sustainability of complementary forage systems, repla...

  20. Productive Life Credits for Cows Revised

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An economic definition of productive life (PL) was introduced to replace the previous definition used since 1994. Cows now get credit for continuing in milk after 305 days of lactation and after 84 months of age. Credits now are based on standard lactation curves, with highest credits at the peak of...

  1. Cow's Eye Dissection in the Physics Lab.

    ERIC Educational Resources Information Center

    Lapp, David R.; Keenan, James E.

    1991-01-01

    Proposes the science demonstration of dissecting a cow's eye to integrate biology and physics in the study of optics and lenses. Reviews the anatomy of the eye, describes the visual process and covers topics as index of refraction of the cornea, microscopic receptors, the lens, and the retina. (MDH)

  2. The cows are always right! Evaluating rations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Much of the focus on ration evaluaton has been on herd production and health records and on feed analyses. However, these pieces of information must be evaluated in the context of the variety of factors that may affect the cows. An important part of evaluating a ration is actually assessing the fe...

  3. 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. PMID:20629216

  4. Assessment of serum IGF-1 and ¿-hydroxybutyrate concentrations on reproductive performance prior to calving and breeding in young beef cows grazing native range

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Metabolites involved in the metabolic adaptation to negative energy balance may potentially contribute to regulation of reproductive success. Therefore, the objective of this 4-yr study was to determine the association of serum metabolites, cow BW, BCS, and calf performance on conception date in sp...

  5. Thermoregulatory responses of Holstein and Brown Swiss Heat-Stressed dairy cows to two different cooling systems

    NASA Astrophysics Data System (ADS)

    Correa-Calderon, Abelardo; Armstrong, Dennis; Ray, Donald; DeNise, Sue; Enns, Mark; Howison, Christine

    . Thirty-seven Holstein and 26 Brown Swiss dairy cows were used to evaluate the effect of two different cooling systems on physiological and hormonal responses during the summer. A control group of cows had access only to shade (C). A second group was cooled with spray and fans (S/F) and the third group was under an evaporative cooling system called Korral Kool (KK). The maximum temperature humidity index during the trial was from 73 to 85. Rectal temperatures and respiration rates of the C group were higher (P < 0.05) than those of the S/F and KK groups in both Holstein and Brown Swiss cows. Triiodothyronine levels in milk were higher (P < 0.05) in the KK group than in the S/F and C groups, while cortisol levels were lower (P < 0.05) in the C group than in S/F and KK. There was no significant difference in the hormonal response of the two breeds. These results demonstrate that both cooling systems may be used increase the comfort of Holstein and Brown Swiss cows during summer in hot, dry climates.

  6. Dietary effects of linseed on fatty acid composition of milk and on liver, adipose and mammary gland metabolism of periparturient dairy cows.

    PubMed

    Mach, N; Zom, R L G; Widjaja, H C A; van Wikselaar, P G; Weurding, R E; Goselink, R M A; van Baal, J; Smits, M A; van Vuuren, A M

    2013-05-01

    During the transition period in dairy cows, drastic adaptations within and between key tissues and cell types occur in a coordinated manner to support late gestation, the synthesis of large quantities of milk and metabolic homoeostasis. The start of lactation coincides with an increase of triacylglycerols in the liver, which has been associated with several economically important diseases in dairy cows (i.e. hepatic lipidiosis, mastitis). The polyunsaturated fatty acids have been used to improve liver metabolism and immune function in the mammary gland. Therefore, the effects of dietary linseed supplementation on milk quality and liver, adipose and mammary gland metabolism of periparturient dairy cows were studied in 14 cows that were randomly assigned to control or linseed supplementation. Animals were treated from 3 weeks antepartum until 6 weeks post-partum. Linseed did not modify dry matter intake, but increased milk yield and lactose yield, and decreased milk fat concentration, which coincided with lower proportion of C16 and higher proportions of stearic acid, conjugated linoleic acid and ?-linolenic acid in milk fat. Linseed supplementation did not significantly change the expression of key lipid metabolism genes in liver and adipose tissues, except of glucose transporter 2 (GLUT2) in liver, which was increased in cows supplemented with linseed, suggesting that more glucose was secreted and probably available for lactose synthesis compared with cows fed control diet. Large adaptations of transcription occurred in the mammary gland when dairy cows were supplemented with linseed. The main affected functional modules were related to energy metabolism, cell proliferation and remodelling, as well as the immune system response. PMID:23639022

  7. Intestinal mucosal atrophy and adaptation

    PubMed Central

    Shaw, Darcy; Gohil, Kartik; Basson, Marc D

    2012-01-01

    Mucosal adaptation is an essential process in gut homeostasis. The intestinal mucosa adapts to a range of pathological conditions including starvation, short-gut syndrome, obesity, and bariatric surgery. Broadly, these adaptive functions can be grouped into proliferation and differentiation. These are influenced by diverse interactions with hormonal, immune, dietary, nervous, and mechanical stimuli. It seems likely that clinical outcomes can be improved by manipulating the physiology of adaptation. This review will summarize current understanding of the basic science surrounding adaptation, delineate the wide range of potential targets for therapeutic intervention, and discuss how these might be incorporated into an overall treatment plan. Deeper insight into the physiologic basis of adaptation will identify further targets for intervention to improve clinical outcomes. PMID:23197881

  8. Post-weaning growth of tropically adapted purebred and crossbred calves when finished in a temperate climate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Typically the adaptation of beef cows that is required for the subtropics has been accomplished by using percentage Brahman breeding. Compromised fertility and carcass quality have increased interest in tropically adapted Bos taurus breed types. Tropically adapted cattle have a reputation for poor...

  9. Neuronal Responses to Physiological Stress

    PubMed Central

    Kagias, Konstantinos; Nehammer, Camilla; Pocock, Roger

    2012-01-01

    Physiological stress can be defined as any external or internal condition that challenges the homeostasis of a cell or an organism. It can be divided into three different aspects: environmental stress, intrinsic developmental stress, and aging. Throughout life all living organisms are challenged by changes in the environment. Fluctuations in oxygen levels, temperature, and redox state for example, trigger molecular events that enable an organism to adapt, survive, and reproduce. In addition to external stressors, organisms experience stress associated with morphogenesis and changes in inner chemistry during normal development. For example, conditions such as intrinsic hypoxia and oxidative stress, due to an increase in tissue mass, have to be confronted by developing embryos in order to complete their development. Finally, organisms face the challenge of stochastic accumulation of molecular damage during aging that results in decline and eventual death. Studies have shown that the nervous system plays a pivotal role in responding to stress. Neurons not only receive and process information from the environment but also actively respond to various stresses to promote survival. These responses include changes in the expression of molecules such as transcription factors and microRNAs that regulate stress resistance and adaptation. Moreover, both intrinsic and extrinsic stresses have a tremendous impact on neuronal development and maintenance with implications in many diseases. Here, we review the responses of neurons to various physiological stressors at the molecular and cellular level. PMID:23112806

  10. Evaluation of Coarsely Ground Wheat as a Replacement for Ground Corn in the Diets of Lactating Dairy Cows

    PubMed Central

    Guo, Y. Q.; Zou, Y.; Cao, Z. J.; Xu, X. F.; Yang, Z. S.; Li, S. L.

    2013-01-01

    Eight multiparous Holstein cows (569±47 kg of BW; 84±17 DIM) were used to evaluate the effects of different levels of coarsely ground wheat (CGW) as replacements for ground corn (GC) in diets on feed intake and digestion, ruminal fermentation, lactation performance, and plasma metabolites profiles in dairy cows. The cows were settled in a replicated 4×4 Latin square design with 3-wk treatment periods; four cows in one of the replicates were fitted with rumen cannulas. The four diets contained 0, 9.6, 19.2, and 28.8% CGW and 27.9, 19.2, 9.6, and 0% GC on dry matter (DM) basis, respectively. Increasing dietary levels of CGW, daily DM intake tended to increase quadratically (p = 0.07); however, apparent digestibility of neutral detergent fiber (NDF) and acid detergent fiber (ADF) were significantly decreased (p<0.01) in cows fed the 28.8% CGW diets. Ruminal pH remained in the normal physiological range for all dietary treatments at all times, except for the 28.8% CGW diets at 6 h after feeding; moreover, increasing dietary levels of CGW, the daily mean ruminal pH decreased linearly (p = 0.01). Increasing the dietary levels of CGW resulted in a linear increase in ruminal propionate (p<0.01) and ammonia nitrogen (NH3-N) (p = 0.06) concentration, while ruminal acetate: propionate decreased linearly (p = 0.03) in cows fed the 28.8% CGW diets. Milk production was not affected by diets; however, percentage and yield of milk fat decreased linearly (p = 0.02) when the level of CGW was increased. With increasing levels of dietary CGW, concentrations of plasma beta-hydroxybutyric acid (BHBA) (p = 0.07) and cholesterol (p<0.01) decreased linearly, whereas plasma glucose (p = 0.08), insulin (p = 0.02) and urea nitrogen (p = 0.02) increased linearly at 6 h after the morning feeding. Our results indicate that CGW is a suitable substitute for GC in the diets of dairy cows and that it may be included up to a level of 19.2% of DM without adverse effects on feed intake and digestion, ruminal fermentation, lactation performance, and plasma metabolites if the cows are fed fiber-sufficient diets. PMID:25049874

  11. Isolation of Staphylococcus microti from milk of dairy cows with mastitis.

    PubMed

    Król, Jaros?aw; Wanecka, Anna; Twardo?, Jan; Mrowiec, Jacek; Dropi?ska, Agata; Bania, Jacek; Podkowik, Magdalena; Korzeniowska-Kowal, Agnieszka; Pa?ciak, Mariola

    2016-01-15

    The present paper is a case-report of multiple udder infections in a dairy herd caused by Staphylococcus microti. Over a 22-month period, eleven S. microti isolates from milk samples from 9 cows were collected. The animals experienced subclinical (with one exception) intramammary infections with a high self-cure rate. The identification of the microorganism was carried out by means of two independent approaches: nucleotide sequence analysis of the 16S rRNA gene, as well as some housekeeping genes (sodA, rpoB, dnaJ), and matrix-assisted laser desorption ionization-time of flight mass spectrometry. All S. microti isolates belonged to an apparently single clone (as detected by the RAPD analysis), indicating that the microorganism could adapt, to some degree, to the bovine mammary gland or even spread from cow to cow in a contagious manner. This report is, to our knowledge, the first ever case of bovine mastitis caused by S. microti and the first instance of isolation of this microorganism from domesticated animals. PMID:26711044

  12. Presence of adropin, nesfatin-1, apelin-12, ghrelins and salusins peptides in the milk, cheese whey and plasma of dairy cows.

    PubMed

    Aydin, Suleyman

    2013-05-01

    Biological fluids (milk and serum/plasma) and cheese whey milk-derived fluid contain numerous molecules, especially amino acids and proteins. Therefore, the purpose of this study was to find out whether cheese whey (n:6), cow milk (n:6) and its blood (n=6) have adropin, nesfatin-1, apelin-12, ghrelins and salusin peptides. Adropin, nesfatin-1, apelin-12 concentrations were measured by ELISA, whereas ghrelin and salusin concentrations were measured by EIA methods. It was found that adropin, nesfatin-1, apelin-12, des-acylated ghrelin and salusins in cheese whey were higher than in the corresponding milk peptides and plasma of dairy cows, with the exception of salusin alpha and acylated ghrelin in milk being the same than that of the corresponding cheese whey concentration and plasma of dairy cows. A correlation was also found between milk peptides and cheese whey, as also with plasma of dairy cows. The data suggest that peptides in cow milk might be an important and nutritious food for (neonatal) calves and human diet due to their biological and physiological properties. PMID:23454173

  13. The western painted turtle genome, a model for the evolution of extreme physiological

    E-print Network

    Shaffer, H. Bradley

    The western painted turtle genome, a model for the evolution of extreme physiological adaptations://genomebiology.com/2013/14/3/R28 (28 March 2013) #12;RESEARCH Open Access The western painted turtle genome, a model for the evolution of extreme physiological adaptations in a slowly evolving lineage H Bradley Shaffer1,2* , Patrick

  14. Canadian media representations of mad cow disease.

    PubMed

    Boyd, Amanda D; Jardine, Cynthia G; Driedger, S Michelle

    2009-01-01

    A Canadian case of bovine spongiform encephalopathy (BSE) or "mad cow disease" was confirmed in May, 2003. An in-depth content analysis of newspaper articles was conducted to understand the portrayal of BSE and variant Creutzfeldt-Jakob disease (vCJD) in the Canadian media. Articles in the "first 10 days" following the initial discovery of a cow with BSE in Canada on May 20, 2003, were examined based on the premise that these initial stories provide the major frames that dominate news media reporting of the same issue over time and multiple occurrences. Subsequent confirmed Canadian cases were similarly analyzed to determine if coverage changed in these later media articles. The results include a prominence of economic articles, de-emphasis of health aspects, and anchoring the Canadian outbreak to that of Britain's crisis. The variation in media representations between those in Canada and those documented in Britain are explored in this study. PMID:19697246

  15. Effects of alfalfa and cereal straw as a forage source on nutrient digestibility and lactation performance in lactating dairy cows.

    PubMed

    Wang, B; Mao, S Y; Yang, H J; Wu, Y M; Wang, J K; Li, S L; Shen, Z M; Liu, J X

    2014-12-01

    This study was conducted to investigate the nutrient digestibility and lactation performance when alfalfa was replaced with rice straw or corn stover in the diet of lactating cows. Forty-five multiparous Holstein dairy cows were blocked based on days in milk (164 ± 24.8 d; mean ± standard deviation) and milk yield (29.7 ± 4.7 kg; mean ± standard deviation) and were randomly assigned to 1 of 3 treatments. Diets were isonitrogenous, with a forage-to-concentrate ratio of 45:55 [dry matter (DM) basis] and contained identical concentrate mixtures and 15% corn silage, with different forage sources (on a DM basis): 23% alfalfa hay and 7% Chinese wild rye hay (AH), 30% corn stover (CS), and 30% rice straw (RS). The experiment was conducted over a 14-wk period, with the first 2 wk for adaptation. The DM intake of the cows was not affected by forage source. Yield of milk, milk fat, protein, lactose, and total solids was higher in cows fed diets of AH than diets of RS or CS, with no difference between RS and CS. Contents of milk protein and total solids were higher in AH than in RS, with no difference between CS and AH or RS. Feed efficiency (milk yield/DM intake) was highest for cows fed AH, followed by RS and CS. Cows fed AH excreted more urinary purine derivatives, indicating that the microbial crude protein yield may be higher for the AH diet than for RS and CS, which may be attributed to the higher content of fermentable carbohydrates in AH than in RS and CS. Total-tract apparent digestibilities of all the nutrients were higher in cows fed the AH diet than those fed CS and RS. The concentration of rumen volatile fatty acids was higher in the AH diet than in CS or RS diets, with no difference between CS and RS diets. When the cereal straw was used to replace alfalfa as a main forage source for lactating cows, the shortage of fermented energy may have reduced the rumen microbial protein synthesis, resulting in lower milk protein yield, and lower nutrient digestibility may have restricted milk production. PMID:25262188

  16. Methane Emission and Milk Production of Dairy Cows Grazing Pastures Rich in Legumes or Rich in Grasses in Uruguay

    PubMed Central

    Dini, Yoana; Gere, José; Briano, Carolina; Manetti, Martin; Juliarena, Paula; Picasso, Valentin; Gratton, Roberto; Astigarraga, Laura

    2012-01-01

    Simple Summary GHGs emissions are relevant in evaluating environmental impact of farming systems. Methane (CH4) produced by enteric fermentation accounts for half of all anthropogenic emissions of GHGs in Uruguay, where ruminant production is based on year round grazing of forages. Here we compared milk production and CH4 emissions by dairy cows grazing two contrasting mixed pastures (rich in legumes or rich in grasses) using the SF6 tracer technique adapted to collect breath samples over 5-days periods. There were no differences in milk or CH4 production between the contrasting pastures, probably because of the high herbage allowance that enabled selective grazing by cows. Abstract Understanding the impact of changing pasture composition on reducing emissions of GHGs in dairy grazing systems is an important issue to mitigate climate change. The aim of this study was to estimate daily CH4 emissions of dairy cows grazing two mixed pastures with contrasting composition of grasses and legumes: L pasture with 60% legumes on Dry Matter (DM) basis and G pasture with 75% grasses on DM basis. Milk production and CH4 emissions were compared over two periods of two weeks during spring using eight lactating Holstein cows in a 2 × 2 Latin square design. Herbage organic matter intake (HOMI) was estimated by chromic oxide dilution and herbage organic matter digestibility (OMD) was estimated by faecal index. Methane emission was estimated by using the sulfur hexafluoride (SF6) tracer technique adapted to collect breath samples over 5-day periods. OMD (0.71) and HOMI (15.7 kg OM) were not affected by pasture composition. Milk production (20.3 kg/d), milk fat yield (742 g/d) and milk protein yield (667 g/d) were similar for both pastures. This may be explained by the high herbage allowance (30 kg DM above 5 cm/cow) which allowed the cows to graze selectively, in particular in grass sward. Similarly, methane emission expressed as absolute value (368 g/d or 516 L/d) or expressed as methane yield (6.6% of Gross Energy Intake (GEI)) was not affected by treatments. In conclusion, at high herbage allowance, the quality of the diet selected by grazing cows did not differ between pastures rich in legumes or rich in grasses, and therefore there was no effect on milk or methane production. PMID:26486922

  17. Mature Runt Cow Lumbar Intradiscal Pressures And Motion Segment Biomechanics

    PubMed Central

    Buttermann, Glenn Robin; Beaubien, Brian P; Saeger, Louis C

    2009-01-01

    Background Context The optimal animal model for in vivo testing of spinal implants, particularly total or partial disc replacement devices, has not yet been determined. Mechanical and morphological similarities of calf and human spines have been reported; however, limitations of the calf model include open growth plates and oversized vertebrae with growth. Mature runt cows (Corrientes breed) may avoid these limitations. Purpose This study compared vertebral morphology and biomechanical properties of human and runt cow lumbar motion segments. Study Design In vivo disc pressure measurements were obtained in six mature runt cows at L4–5. In vitro evaluation was performed on these same segments and repeated on twelve human motion segments. Methods Disc pressures were measured in vivo in runt cow (Corrientes breed) L45 discs using a percutaneous transducer with the animal performing various activities. These motion segments were then harvested and morphologic and biomechanical evaluations (disc pressure in compression, flexibility tests to 7.5 Nm) were performed on both cow and male human L23 and L45 segments. Results The transverse lumbar disc dimensions were slightly smaller for (mixed gender) cow vs. (male) humans, but were within the range of reported (mixed gender) human values. The mean ± SD disc height was smaller for runt cow (7 ± 1 mm) vs. human discs (13 ± 2 mm, p<0.001). The vertebral bodies of the cow were approximately twice as tall as the human. In vitro testing revealed significantly greater disc pressure response to applied axial loading in the runt cow vs. humans (1.27 ± 0.18 kPa/N vs. 0.84 ± 0.15 kPa/N respectively) but similar overall stiffness (2.15 ± 0.71 kN/mm vs. 1.91 ± 0.94 kN/mm, respectively). Runt cow and human segments flexibility curves were similar with the following exceptions: runt cow stiffness was ~40% greater in torsion (p<0.05), runt cow segment lateral bending motion was greater vs. humans (range of motion by 30%, neutral zone by 100%; both p<0.05) and flexion range of motion tended to be smaller in runt cow vs. human specimens (by ~40%, p=NS). In vivo, the standing disc pressure in the runt cow was 0.80 ± 0.24 MPa. Conclusions Although no animal replicates the human motion segment, the runt cow lumbar spine had a number of biomechanical and morphological measurements within the range of human values. The closed physes and temporally stable morphology of the mature runt cow may make this model more suitable vs. standard calf models for human intradiscal implant studies. PMID:18037351

  18. Electrostatic Radionuclide Separation: A New Version of Rutherford's "Thorium Cow".

    ERIC Educational Resources Information Center

    Eiswirth, Marcus; And Others

    1982-01-01

    Describes three experiments (also useful as demonstrations) using a "thorium cow," a device which concentrates the daughter products from thorium compounds by precipitation on a charged electrode. (JN)

  19. Chemotherapeutic potential of cow urine: A review

    PubMed Central

    Randhawa, Gurpreet Kaur; Sharma, Rajiv

    2015-01-01

    In the grim scenario where presently about 70% of pathogenic bacteria are resistant to at least one of the drugs for the treatment, cue is to be taken from traditional/indigenous medicine to tackle it urgently. The Indian traditional knowledge emanates from ayurveda, where Bos indicus is placed at a high pedestal for numerous uses of its various products. Urine is one of the products of a cow with many benefits and without toxicity. Various studies have found good antimicrobial activity of cow’s urine (CU) comparable with standard drugs such as ofloxacin, cefpodoxime, and gentamycin, against a vast number of pathogenic bacteria, more so against Gram-positive than negative bacteria. Interestingly antimicrobial activity has also been found against some resistant strains such as multidrug-resistant (MDR) Escherichia coli and Klebsiella pneumoniae. Antimicrobial action is enhanced still further by it being an immune-enhancer and bioenhancer of some antibiotic drugs. Antifungal activity was comparable to amphotericin B. CU also has anthelmintic and antineoplastic action. CU has, in addition, antioxidant properties, and it can prevent the damage to DNA caused by the environmental stress. In the management of infectious diseases, CU can be used alone or as an adjunctive to prevent the development of resistance and enhance the effect of standard antibiotics. PMID:26401404

  20. Comparison of milk produced by cows cloned by nuclear transfer with milk from non-cloned cows.

    PubMed

    Walsh, Marie K; Lucey, John A; Govindasamy-Lucey, Selvarani; Pace, Marvin M; Bishop, Michael D

    2003-01-01

    Cloning technologies, including embryo splitting and nuclear transfer, were introduced into dairy cattle breeding in the early 1980s. With the recent worldwide attention on the cloning of sheep ("Dolly") and cows ("Gene"), the potential food safety concerns for food products derived from cloned animals needs to be addressed. There has been no study of the composition of milk produced by cloned cows. In this preliminary study, we evaluated the composition of milk from 15 lactating non-embryonic cell cloned cows and six non-cloned lactating cows over a single season. The cloned cows came from five unique genetic lines and three distinct breeds. Milk samples were analyzed for total solids, fat, fatty acid profile, lactose, protein and compared to non-cloned and literature values. Gross chemical composition of milk from cloned cows was similar to that of the non-cloned cows and literature values. Our results lead us to conclude that there are no obvious differences in milk composition produced from cloned cows compared to non-cloned cows. PMID:14588139

  1. Reproduction, Physiology and Biochemistry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter focuses on the reproduction, physiology, and biochemistry of the root-knot nematodes. The extensive amount of information on the reproduction and cytogenetics of species of Meloidogyne contrasts with the limited information on physiology, biochemistry, and biochemical pathways. In commo...

  2. Microbial physiology vol. 29

    SciTech Connect

    Rose, A.H. ); Tempest, D.W. )

    1988-01-01

    This book contains the following chapters: Hydrogen metabolism in Rhizobium: energetics, regulation, enzymology and genetics; The physiology and biochemistry of pili; Carboxysomes and ribulose bisphosphate carboxylase/oxygenase; Archaebacteria: the comparative enzymology of their central metabolic pathways; and Physiology of lipoteichoic acids in bacteria.

  3. Phun Week: Understanding Physiology

    ERIC Educational Resources Information Center

    Limson, Mel; Matyas, Marsha Lakes

    2009-01-01

    Topics such as sports, exercise, health, and nutrition can make the science of physiology relevant and engaging for students. In addition, many lessons on these topics, such as those on the cardiovascular, respiratory, and digestive systems, align with national and state life science education standards. Physiology Understanding Week (PhUn…

  4. Effect of corn silage particle size and supplemental hay on rumen pH and feed preference by dairy cows fed high-starch diets.

    PubMed

    Kmicikewycz, A D; Heinrichs, A J

    2015-01-01

    The objectives of this experiment were to determine the effects of corn silage particle size and supplemental hay on rumen pH and feed preference in lactating dairy cows experiencing a bout of subacute ruminal acidosis (SARA). In this study, 12 lactating (8 ruminally cannulated), multiparous Holstein cows averaging 91±40d in milk and weighing 695±95kg (mean ± SD) were randomly assigned to a replicated 4×4 Latin square. During each of the four 21-d periods, animals were offered 1 of 4 diets that were chemically similar but varied in corn silage particle size and supplemental second cutting orchardgrass hay: short corn silage total mixed ration (TMR; ST); short corn silage TMR with 5.6% supplemental hay (SH); long corn silage TMR (L); and long corn silage TMR with 5.6% supplemental hay (LH). Cows were allowed to adapt to this feeding scheme for 14d, and cannulated cows were then subjected to a rumen challenge to induce a bout of SARA by restricting feed before the challenge and providing 4kg of ground wheat via the rumen cannula. Although baseline pH was low, the SARA challenge lowered ruminal pH further for all cows regardless of diet. Daily average rumen pH decreased from 5.44 and 5.45 to 5.33 and 5.38 for ST and SH, respectively, and from 5.64 and 5.54 to 5.47 and 5.39 for L and LH, respectively, from baseline to challenge phase. Following the rumen challenge, rumen concentrations of acetate, propionate, butyrate, and valerate increased. Decreasing corn silage particle size significantly increased TMR and total DMI during all phases of the model. Feeding short corn silage TMR increased milk, protein, and lactose yields. Cows fed supplemental hay had increased fat yield and protein concentration in the milk and responded minimally to the effects of particle size selection when challenged with SARA. Cows consuming short corn silage TMR changed feed preference for longer forage particles during the course of the SARA challenge. During the recovery phase, however, cows refused an average of 13.5% of the offered TMR and 78.7% of the supplemental hay. These results indicate that cows did not prefer the supplemental hay regardless of corn silage particle size during a bout of SARA, which may have been due to the possible adaptation of a low ruminal pH throughout the study. PMID:25465541

  5. Effect of sensor systems for cow management on milk production, somatic cell count, and reproduction.

    PubMed

    Steeneveld, W; Vernooij, J C M; Hogeveen, H

    2015-06-01

    To improve management on dairy herds, sensor systems have been developed that can measure physiological, behavioral, and production indicators on individual cows. It is not known whether using sensor systems also improves measures of health and production in dairy herds. The objective of this study was to investigate the effect of using sensor systems on measures of health and production in dairy herds. Data of 414 Dutch dairy farms with (n=152) and without (n=262) sensor systems were available. For these herds, information on milk production per cow, days to first service, first calving age, and somatic cell count (SCC) was provided for the years 2003 to 2013. Moreover, year of investment in sensor systems was available. For every farm year, we determined whether that year was before or after the year of investment in sensor systems on farms with an automatic milking system (AMS) or a conventional milking system (CMS), or whether it was a year on a farm that never invested in sensor systems. Separate statistical analyses were performed to determine the effect of sensor systems for mastitis detection (color, SCC, electrical conductivity, and lactate dehydrogenase sensors), estrus detection for dairy cows, estrus detection for young stock, and other sensor systems (weighing platform, rumination time sensor, fat and protein sensor, temperature sensor, milk temperature sensor, urea sensor, ?-hydroxybutyrate sensor, and other sensor systems). The AMS farms had a higher average SCC (by 12,000 cells/mL) after sensor investment, and CMS farms with a mastitis detection system had a lower average SCC (by 10,000 cells/mL) in the years after sensor investment. Having sensor systems was associated with a higher average production per cow on AMS farms, and with a lower average production per cow on CMS farms in the years after investment. The most likely reason for this lower milk production after investment was that on 96% of CMS farms, the sensor system investment occurred together with another major change at the farm, such as a new barn or a new milking system. Most likely, these other changes had led to a decrease in milk production that could not be compensated for by the use of sensor systems. Having estrus detection sensor systems did not improve reproduction performance. Labor reduction was an important reason for investing in sensor systems. Therefore, economic benefits from investments in sensor systems can be expected more from the reduction in labor costs than from improvements in measures of health and production in dairy herds. PMID:25841965

  6. COMPARATIVE GUT PHYSIOLOGY SYMPOSIUM: Comparative physiology of digestion.

    PubMed

    Furness, J B; Cottrell, J J; Bravo, D M

    2015-02-01

    The digestive systems of all species have been shaped by environmental pressures over long evolutionary time spans. Nevertheless, all digestive systems must achieve the same end points, the ingestion of biological material and its conversion to molecules that serve as energy substrates and structural components of tissues. A range of strategies to extract nutrients, including for animals reliant primarily on foregut fermentation, hindgut fermentation, and enzymatic degradation, have evolved. Moreover, animals have adapted to different foodstuffs as herbivores (including frugivores, folivores, granivores, etc.), carnivores, and omnivores. We present evidence that humans have diverged from other omnivores because of the long history of consumption of cooked or otherwise prepared food. We consider them to be cucinivores. We present examples to illustrate that the range of foodstuffs that can be efficiently assimilated by each group or species is limited and is different from that of other groups or species. Differences are reflected in alimentary tract morphology. The digestive systems of each group and of species within the groups are adaptable, with constraints determined by individual digestive physiology. Although overall digestive strategies and systems differ, the building blocks for digestion are remarkably similar. All vertebrates have muscular tubular tracts lined with a single layer of epithelial cells for most of the length, use closely related digestive enzymes and transporters, and control the digestive process through similar hormones and similarly organized nerve pathways. Extrapolations among species that are widely separated in their digestive physiologies are possible when the basis for extrapolation is carefully considered. Divergence is greatest at organ or organismal levels, and similarities are greatest at the cell and molecular level. PMID:26020739

  7. Associations between intrauterine bacterial infection, reproductive tract inflammation, and reproductive performance in pasture-based dairy cows.

    PubMed

    de Boer, Melvin; Buddle, Bryce M; Heuer, Cord; Hussein, Hassan; Zheng, Tao; LeBlanc, Stephen J; McDougall, Scott

    2015-06-01

    Reproductive tract bacterial infections, particularly those caused by Escherichia coli and Trueperella pyogenes, can have a negative impact on reproductive performance. It has been hypothesized that the presence of E coli early postpartum may increase the risk of isolation of T pyogenes later postpartum. The objective of the present study was to examine associations between intrauterine bacterial infections with E coli and T pyogenes and any bacterial growth (irrespective of bacterial species), purulent vaginal discharge (PVD), cytologic evidence of endometritis (an increased proportion of polymorphonuclear cells [PMNs]), and reproductive performance. Dairy cows (n = 272) from six herds were examined at Days 0 (median, 2 days in milk), 21 and 42 postpartum. From each cow two intrauterine samples were collected via triple-guarded cytobrush at Days 0 and 21. The first cytobrush was used for bacteriologic culture. Escherichia coli and T pyogenes were isolated by culture, and E coli isolates were assigned to one of four phylogenetic groups using a two-step triplex polymerase chain reaction. In addition, T pyogenes was confirmed by polymerase chain reaction. The second cytobrush was used to prepare a cytology slide. Nucleated cells (n = 200) were categorized as epithelial cells, PMNs, or macrophages. Cows were also assessed for body condition score, PVD score, the presence of a CL, and pregnancy. Statistical analysis was performed using multivariable models. There was no association between the presence of E coli at Day 0 and probability of isolation of T pyogenes 3 weeks later; however, E coli positive cows at Day 0 were more likely to be diagnosed with E coli at Day 21 (relative risk [RR] = 2.0, P < 0.01). Escherichia coli at Day 0 or T pyogenes at Day 21 increased the risk of PVD diagnosis 3 weeks later (RR = 1.9; P = 0.04 and RR = 3.0; P = 0.05, respectively). Cows with any bacterial growth at Day 21, irrespective of species, were less likely to conceive within 3 weeks after the start of the seasonal breeding program (RR = 0.8; P = 0.05). Interestingly, cows with 25% PMNs or greater at Day 0 had shorter time to pregnancy (hazard ratio = 1.32; P = 0.05). Intrauterine bacterial infection may impair reproductive performance but the presence of E coli was not associated with isolation of T pyogenes 3 weeks later. Increased endometrial flux of PMNs in cows early postpartum may be a physiological process and improve reproductive performance. PMID:25801340

  8. Space physiology and medicine (2nd edition)

    NASA Technical Reports Server (NTRS)

    Nicogossian, Arnauld E. (editor); Huntoon, Carolyn Leach (editor); Pool, Sam L. (editor)

    1989-01-01

    The fundamental biomedical issues involved in manned space flight are examined in review chapters contributed by leading U.S. experts. Sections are devoted to the history of manned space flight, the space environment, space-flight systems and procedures, physiological adaptation to space flight, health maintenance of space crewmembers, and medical problems of space flight. Extensive diagrams, drawings, graphs, photographs, and tables of numerical data are provided.

  9. Genetics and the physiological ecology of conifers

    SciTech Connect

    Mitton, J.B.

    1995-07-01

    Natural selection acts on the diversity of genotypes, adapting populations to their specific environments and driving evolution in response to changes in climate. Genetically based differences in physiology and demography adapt species to alternate environments and produce, along with historical accidents, the present distribution of species. The sorting of conifer species by elevation is so marked that conifers help to define plant communities arranged in elevational bands in the Rocky Mountains. For these reasons, a genetic perspective is necessary to appreciate the evolution of ecophysiological patterns in the coniferous forests of the Rocky Mountains. The fascinating natural history and the economic importance of western conifers have stimulated numerous studies of their ecology, ecological genetics, and geographic variation. These studies yield some generalizations, and present some puzzling contradictions. This chapter focuses on the genetic variability associated with the physiological differences among genotypes in Rocky Mountain conifers. Variation among genotypes in survival, growth, and resistance to herbivores is used to illustrate genetically based differences in physiology, and to suggest the mechanistic studies needed to understand the relationships between genetic and physiological variation.

  10. Cow, sheep and llama manure at psychrophilic anaerobic co-digestion with low cost tubular digesters in cold climate and high altitude.

    PubMed

    Martí-Herrero, J; Alvarez, R; Cespedes, R; Rojas, M R; Conde, V; Aliaga, L; Balboa, M; Danov, S

    2015-04-01

    The aim of this research is to evaluate the co-digestion of cow and llama manure combined with sheep manure, in psychrophilic conditions and real field low cost tubular digesters adapted to cold climate. Four digesters were monitored in cold climate conditions; one fed with cow manure, a second one with llama manure, the third one with co-digestion of cow-sheep manure and the fourth one was fed with llama-sheep manure. The slurry had a mean temperature of 16.6 °C, the organic load rate was 0.44 kgvs m(-3) d(-1) and the hydraulic retention time was 80 days. After one hundred days biogas production was stable, as was the methane content and the pH of the effluent. The co-digestion of cow-sheep manure results in a biogas production increase of 100% compared to the mono-digestion of cow manure, while co-digestion of llama-sheep manure results in a decrease of 50% in biogas production with respect to mono-digestion of llama manure. PMID:25656868

  11. A La Carts: You Want Wireless Mobility? Have a COW

    ERIC Educational Resources Information Center

    Villano, Matt

    2006-01-01

    Computers on wheels, or COWs, combine the wireless technology of today with the audio/visual carts of yesteryear for an entirely new spin on mobility. Increasingly used by districts with laptop computing initiatives, COWs are among the hottest high-tech sellers in schools today, according to market research firm Quality Education Data. In this…

  12. Calf Removal: A Way to Stimulate Reproduction in Cows 

    E-print Network

    Sprott, L. R.

    2003-10-08

    Cows that are slow to breed or fail to breed are costly to producers. One of the factors that delays the resumption of estrous activity in a cow--and subsequent breeding--is nursing stress. Removing a calf from a dam, either short...

  13. Rubber Flooring Impact on Health of Dairy Cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Use of rubber flooring in dairies has become popular because of perceived cow comfort. The objective of this longitudinal study was to evaluate locomotion, health, production, and immunity over the first 180d of each of the 1st and 2nd lactations of cows assigned to free-stall housing with either r...

  14. 21 CFR 1210.12 - Physical examination of cows.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Physical examination of cows. 1210.12 Section 1210... FEDERAL IMPORT MILK ACT Inspection and Testing § 1210.12 Physical examination of cows. (a) Physical.... (b) The result of the physical examination shall be set forth in the form prescribed by the Secretary....

  15. 21 CFR 1210.12 - Physical examination of cows.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Physical examination of cows. 1210.12 Section 1210... FEDERAL IMPORT MILK ACT Inspection and Testing § 1210.12 Physical examination of cows. (a) Physical.... (b) The result of the physical examination shall be set forth in the form prescribed by the Secretary....

  16. Utilization of Whole Cottonseed and Hay in Beef Cow Diets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over a 3-yr period, cow wintering experiments were designed to determine free-choice intake of WCS (whole cottonseed) by mature beef cows during winter, and the effects on diet digestibility when WCS was fed at recommended levels (0.05% body weight) and free-choice. In a 2007 study, the potential va...

  17. EOSINOPHILIC MYOSITIS DUE TO SARCOCYSTIS HOMINIS IN A BEEF COW

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A case of eosinophilic myositis in an eight-year-old beef cow was investigated. The cow originated from a herd that had a high incidence of eosinophilic myositis in slaughtered adult females during a period of two years. Histologically, the lesions in the muscles were characterized as granulomas wit...

  18. Laryngeal obstruction caused by lymphoma in an adult dairy cow

    PubMed Central

    Lardé, Hélène; Nichols, Sylvain; Babkine, Marie; Chénier, Sonia

    2014-01-01

    A Holstein cow was presented for inspiratory dyspnea. Endoscopic evaluation revealed swollen arytenoids and a presumptive diagnosis of bilateral arytenoidal chondritis was made. A partial arytenoidectomy was performed, the right arytenoid was submitted for histopathology, and a diagnosis of laryngeal lymphoma was made. Due to the poor prognosis, the cow was euthanized. PMID:24489391

  19. Milk drop due to leptospirosis in dairy cows.

    PubMed

    2015-03-01

    Leptospiral milk drop in dairy cows. Pseudomonas aeruginosa mastitis in a cow. Systemic pasteurellosis in lambs. Encephalopathy due to water deprivation/salt poisoning suspected in weaned lambs. Biliary cystadenoma in a red deer hind. These are among matters discussed in the disease surveillance report for November 2014 from SAC Consulting: Veterinary Services (SAC C VS). PMID:25748187

  20. Rubber Flooring Impact on Production and Herdlife of Dairy Cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Use of rubber flooring in dairies has become popular because of perceived cow comfort. The overall objective of this longitudinal study was to evaluate production, reproduction, and retention of first and second lactations of cows assigned to either rubber (RUB) or concrete (CON) flooring at the fe...

  1. Manure Nutrient Excretion by Jersey and Holstein Cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective was to evaluate feces, urine, and nitrogen (N) excretion by Jersey and Holstein cows. Sixteen multiparous cows (n=8 per breed) were fed two experimental rations at calving in a switchback experimental design. Diets were 50% forage and based on corn meal (control) or whole cottonseed. H...

  2. Intake and digestibility of low and high quality forage diets by purebred and cross-bred steers of tropically adapted breeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To improve the overall value of calves from the southern US cow herds, while maintaining tropical adaptation, tropically adapted Bos indicus and Bos taruus breeds are being evaluated. The objectives of these studies were to determine the impact of tropical adapted breed type on DMI and digestibility...

  3. Anorectal physiology and testing.

    PubMed

    Van Koughnett, Julie Ann M; da Silva, Giovanna

    2013-12-01

    A good understanding of anorectal physiology is essential for the diagnosis and appropriate treatment of various anorectal disorders, such as fecal incontinence, constipation, and pain. This article reviews the physiology of the anorectum and details the various investigations used to diagnose anorectal physiology disorders. These anatomic and functional tests include anal manometry, endoanal ultrasound, defecography, balloon expulsion test, magnetic resonance imaging, pudendal nerve terminal motor latency, electromyography, and colonic transit studies. Indications for investigations, steps in performing the tests, and interpretation of results are discussed. PMID:24280396

  4. Physiology & Development of Chronic Fear

    E-print Network

    Dennis, Nancy

    A Individual B interest fear physiology physiology Individual A Temperament, Physiology, and Health health - Longitudinal studies - birth to death McClintock, 1982 - Evidence of temperament/personality: behavioral

  5. Measures of daily distribution patterns of cow calf pairs using global positioning systems on both cows and calves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    GPS collars were used to describe the daily distribution patterns of cows and their calves from 18 to 60 days postpartum on pinyon juniper-shortgrass rangeland in central New Mexico. Eighteen, 3 year old cows and their calves were fitted weekly with GPS collars for seven consecutive weeks. Twenty da...

  6. Cool-season annual pastures with clovers to supplement wintering beef cows nursing calves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Every December, for 3 years, 87 beef cows, nursing cows, (594 ' 9.8 kg; calving season, September to November) were stratified by body condition score, body weight, cow age, and calf gender. They were divided randomly into 6 groups and assigned to 1 of 6 cool-season annual swards (0.45 hectares/cow...

  7. Effect on Production of Replacing Dietary Starch With Sucrose in Lactating Dairy Cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Replacing dietary starch with sugar has been reported to improve production in dairy cows. Two sets of 24 Holstein cows averaging 41 kg/d of milk were fed a covariate diet and then blocked by DIM and randomly assigned in two phases to four groups of 6 cows each. Cows were fed experimental diets cont...

  8. Does diverse grazing behavior of suckler cows have an impact on predicted methane emissions?

    PubMed

    Ricci, P; Umstätter, C; Holland, J P; Waterhouse, A

    2014-03-01

    A modeling study based on a dataset from a large-scale grazing study was used to identify the potential impact of grazing behavior and performance of diverse cow genotypes on predicted methane (CH4) emissions. Lactating cows grazing extensive seminatural grassland and heath vegetation were monitored with Global Positioning System collars and activity sensors. The diet selected by cows of 3 different genotypes, Aberdeen Angus cross Limousin (AxL), Charolais (CHA), and Luing (LUI), was simulated by matching their locations during active periods with hill vegetation maps. Measured performance and activity were used to predict energy requirements, DMI, and CH4 output. The cumulative effect of actual performance, diet selection, and actual physical activity on potential CH4 output and yield was estimated. Sensitivity analyses were performed for the digestibility of intake, energy cost of activity, proportion of milk consumed by calves, and reproductive efficiency. Although with a better performance (P < 0.05), LUI required less total energy than the other genotypes (P < 0.001) as the other 2 spent more energy for maintenance (P < 0.001) and activity (P < 0.001). By selecting a better quality diet (P < 0.03), estimated CH4 of CHA cow-calf pairs was lower than AxL (P = 0.001) and slightly lower than LUI (P = 0.08). Energy lost as CH4 was 0.17 and 0.58% lower for LUI than AxL and CHA (P < 0.002). This study suggests for the first time that measured activity has a major impact on estimated CH4 outputs. A 15% difference of the cow-calf pair CH4 was estimated when using different coefficients to convert actual activity into energy. Predicted CH4 was highly sensitive to small changes in diet quality, suggesting the relative importance of diet selection on heterogeneous rangelands. Extending these results to a farm systems scale, CH4 outputs were also highly sensitive to reductions in weaning rates, illustrating the impact on CH4 at the farm-system level of using poorly adapted genotypes on habitats where their performances may be compromised. This paper demonstrates that variations in grazing behavior and grazing choice have a potentially large impact on CH4 emissions, illustrating the importance of including these factors in calculating realistic national and global estimates. PMID:24665106

  9. Perforated Duodenal Ulcer in a Cow

    PubMed Central

    Fatimah, I.; Butler, D. G.; Physick-Sheard, P. W.

    1982-01-01

    A case report of perforated duodenal ulcer in a ten year old Holstein cow is presented. On three occasions, sudden anorexia and rapidly progressing abdominal fluid distension were associated with metabolic alkalosis, hypochloremia and hypokalemia. Rumen fluid at the time of the second episode was acidic and contained an excessive amount of chloride ion. An abdominal mass dorsal to the abomasum involving the pylorus and several loops of small bowel was identified but not corrected at surgery. Necropsy confirmed a 1.5 cm diameter duodenal ulcer 6 cm distal to the pylorus. PMID:17422146

  10. The Vitamin A Requirements of Dairy Cows

    E-print Network

    Fraps, G. S. (George Stronach); Copeland, O. C. (Orlin Cephas); Treichler, Ray

    1934-01-01

    . L., 1933. The vitamin A content of rat liver after feeding with alpha, beta and gamma carotene, and - . the antimony trichloride reaction of vitamin A preparations. (Z. Physiol. Chem. 221:117) Chemical Abstracts, 28:806. THE VITAMIN A...RICULTURAL LLLUL, CAMPU EXPERIMENT 7%" A. R. CONNER, DIRECTOR COLLEGE STATION, BRAZOS COUNTY, TEXAS TIN NO. 495 AUGUST, 193g :3= -a c 3 DIVISION OF CHEMISTRY I'HE VITAMIN A REQUIREMENTS OF DAIRY COWS GRICULTURAL AND MECHANICAL COLLEGE OF TEXAS T. 0...

  11. Wheat Versus Milo for Dairy Cows

    E-print Network

    Copeland, O. C. (Orlin Cephas)

    1933-01-01

    effects from this feeding. They recommended that wheat be crushed or only coarsely ground for feeding to cows since finely-ground wheat has a tendency to form a pasty, gummy mass in the course of digestion. Jacobs (5) of Panhandle Station (Oklahoma.... Although the chemical analysis of the two feeds show that at is approximately two per cent higher in crude protein than milo, adjustment in protein was made for this difference in formulating tne two grain mixtures, as it was the object...

  12. Nutrient Requirements of the Cow and Calf. 

    E-print Network

    Maddox, L. A. Jr.

    1965-01-01

    of the Cow and Calf TEXAS A&M UNIVERSITY TEXAS AGRICULTURAL EXTENSION SERVICE, J. E. Hutchison, Director College Station, Texas I contents I-. Energy Requirements, 3 Protein Requirements, 8 Daily Nutrient Requirements and Minimum Feed Quality, 9... to weaning. (Maintenance of dams not included) -- Pounds of digestible protein Age in mo. Required In milk Nec. for Additional nec. From pastures milk prod. calf gain Daily Monthly 300 Ib. calf at 7 mo. Prenatal 1 .36 2 .40 3 .44 4 .48 5 .51 6...

  13. The Physiology of Creativity

    ERIC Educational Resources Information Center

    Loch, Charles

    1978-01-01

    The author reviews the theoretical base and practical implementation of human development counseling, by which the individual identifies the environmental and physiological conditions that facilitate creativity and learns to manage those conditions to enhance creativity. (CL)

  14. Photosynthesis: Physiological and

    E-print Network

    Ehleringer, Jim

    Photosynthesis: Physiological and Ecological Considerations Chapter 9 THE CONVERSION OF SOLAR reactions of photosynthesis should not overshadow the fact that, under natural condi- tions. The impact of the environment on photosynthesis is of interest to plant physiologists, ecologists

  15. Simulator produces physiological waveforms

    NASA Technical Reports Server (NTRS)

    Ekeroot, S.

    1965-01-01

    Physiological waveform simulator is capable of producing signals to simulate an axiliary and a sternal electrocardiogram, blood pressure, respiratory rate and body temperature. This may be used to check out bioinstrumentation.

  16. Reproduction, physiology and biochemistry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter summarizes fundamental knowledge and recent discoveries about the reproduction, physiology and biochemistry of plant-parasitic nematodes. Various types of reproduction are reviewed, including sexual reproduction and mitotic and meiotic parthenogenesis. Although much is known about the p...

  17. Thyroid physiology and immunology.

    PubMed

    Bergman, D A

    1990-04-01

    The thyroid gland, like the paintings of Chagall, has forced us to look at our traditional understanding of things in a new way and to gain fresh insight into ancient concepts of human physiology. PMID:2186334

  18. Biomethanization of sugar beet byproduct by semi-continuous single digestion and co-digestion with cow manure.

    PubMed

    Aboudi, Kaoutar; Álvarez-Gallego, Carlos José; Romero-García, Luis Isidoro

    2016-01-01

    Dried pellet of exhausted sugar beet cossettes were digested alone and combined with cow manure as co-substrate in a mesophilic semi-continuous anaerobic system. In single digestion assay, the stable biogas production and stable reactor operation was observed at the hydraulic retention time (HRT) of 20days (OLR: 3.26gVS/Lreactord) which was the minimum HRT tolerated by the system. However, co-digestion with cow manure allowed to decrease the HRT until 15days (OLR: 4.97gVS/Lreactord) with 32% higher biogas generation and efficient reactor operation. Propionic acid was the predominant VFA observed during single digestion assay failure, while acetic acid accumulation was observed in the co-digestion assay. In both single and co-digestion assays, the recovery of digesters was possible by ceasing the feeding and re-inoculation with a well-adapted inoculum. PMID:26512853

  19. Heterosis and heterosis retention for reproductive and maternal traits in Brahman - British crossbred cows 

    E-print Network

    Key, Kelli Loren

    2005-02-17

    traits were analyzed for Angus (A), Brahman (B), and Hereford (H) straightbred cows; F1 and F2 BA and BH cows; and 3/8 B 5/8 A first (Bn) and second (Bn2) generation cows in Central Texas. Heterosis was estimated for calf crop born (CCB), calf crop... weaned (CCW), and cow weight at palpation (PW) by linear contrasts within cow breed groups. F1 BA cows expressed heterosis (PF2 BA cows expressed negative heterosis (P<0.10) for CCB (-0.06) and CCW (-0...

  20. Effect of propylene glycol on adipose tissue mobilization in postpartum over-conditioned Holstein cows.

    PubMed

    Bjerre-Harpøth, V; Storm, A C; Eslamizad, M; Kuhla, B; Larsen, M

    2015-12-01

    Our objective was to investigate the quantitative and qualitative effects of propylene glycol (PG) allocation on postpartum adipose tissue mobilization in over-conditioned Holstein cows. Nine ruminally cannulated and arterially catheterized cows were, at parturition, randomly assigned to a ruminal pulse dose of either 500g of tap water (n=4) or 500g of PG (n=5) once a day. The PG was given with the morning feeding for 4 wk postpartum (treatment period), followed by a 4-wk follow-up period. All cows were fed the same prepartum and postpartum diets. At -16 (±3), 4 (±0), 15 (±1) and 29 (±2) days in milk (DIM), body composition was determined using the deuterium oxide dilution technique, liver and subcutaneous adipose tissue biopsies were collected, and mammary gland nutrient uptake was measured. Weekly blood samples were obtained during the experiment and daily blood samples were taken from -7 to 7 DIM. Postpartum feed intake and milk yield was not affected by PG allocation. The body content of lipid was not affected by treatment, but tended to decrease from 4 to 29 DIM with both treatments. Except for the first week postpartum, no difference in plasma nonesterified fatty acids concentration was noted between treatments in the treatment period. Yet, PG allocation resulted in decreased plasma concentrations of ?-hydroxybutyrate (BHB) and increased plasma concentrations of glucose. In the follow-up period, plasma concentrations of nonesterified fatty acids, glucose, and BHB did not differ between treatments. Additionally, the change in abundance of proteins in adipose tissue biopsies from prepartum to 4 DIM was not affected by treatment. In conclusion, the different variables to assess body fat mobilization were concurrent and showed that a 4-wk postpartum PG allocation had limited effect on adipose tissue mobilization. The main effect was an enhanced glucogenic status with PG. No carry-over effect of PG allocation was recorded for production or plasma metabolites, and, hence, a new period of metabolic adaption to lactation seemed to occur with PG treatment after ceasing PG allocation. Thus, PG seemed to induce a 2-step adaption to lactation, reducing the immediate postpartum nadir and peak of plasma concentration of glucose and BHB, respectively; which is beneficial for postpartum cows at high risk of lipid-related metabolic diseases. PMID:26454303

  1. Effects of a high-energy diet on oocyte quality and in vitro embryo production in Bos indicus and Bos taurus cows.

    PubMed

    Sales, J N S; Iguma, L T; Batista, R I T P; Quintão, C C R; Gama, M A S; Freitas, C; Pereira, M M; Camargo, L S A; Viana, J H M; Souza, J C; Baruselli, P S

    2015-05-01

    The effects of different dietary energy levels [100 and 170% for maintenance (M) and high energy (1.7M), respectively] on metabolic, endocrine, and reproductive parameters were evaluated in nonlactating Bos indicus (Gir; n=14) and Bos taurus (Holstein; n=14) cows submitted to ultrasound-guided ovum pick-up followed by in vitro embryo production. The oocyte donor cows were housed in a tiestall system and fed twice daily (0800 and 1600 h). Twenty-one days before the beginning of the experiment, the animals were fed with a maintenance diet for adaptation followed by the experimental diets (M and 1.7M), and each cow underwent 9 ovum pick-up procedures 14 d apart. The recovered oocytes were cultured in vitro for 7 d. We measured glucose and insulin concentrations and performed glucose tolerance tests and the relative quantification of transcripts (PRDX1, HSP70.1, GLUT1, GLUT5, IGF1R, and IGF2R) from the oocytes recovered at the end of the experimental period. No interactions were observed between the effects of genetic groups and dietary energy level on the qualitative (viable oocytes, quality grade, and oocyte quality index) and quantitative (oocytes recovered) oocyte variables. There were no effects of dietary energy level on the qualitative and quantitative oocyte variables. However, Bos indicus cows had greater numbers of recovered structures, viable oocytes, and A and B oocyte grades as well as better oocyte quality index scores and lower DNA fragmentation rates compared with Bos taurus donors. In vitro embryo production (cleavage and blastocyst rates and number of embryos) was similar between diets, but the 1.7M diet reduced in vitro embryo production in Bos indicus cows after 60 d of treatment. Moreover, Bos indicus cows on the 1.7M diet showed lower transcript abundance for the HSP70.1, GLUT1, IGF1R, and IGF2R genes. All cows fed 1.7M diets had greater glucose and insulin concentrations and greater insulin resistance according to the glucose tolerance test. In conclusion, increasing dietary energy did not interfere with oocyte numbers and quality, but the 1.7M diet reduced in vitro embryo production in Bos indicus cows after 60 d of treatment. Finally, Bos indicus cows had greater oocyte quality, greater numbers of viable oocytes and greater in vitro embryo yield than Bos taurus. PMID:25726114

  2. Factors associated with colostral specific gravity in dairy cows.

    PubMed

    Morin, D E; Constable, P D; Maunsell, F P; McCoy, G C

    2001-04-01

    The objectives of this study were to identify factors associated with colostral specific gravity in dairy cows, as measured by a commercially available hydrometer (Colostrometer). Colostral specific gravity was measured in 1085 first-milking colostrum samples from 608 dairy cows of four breeds on a single farm during a 5-yr period. Effects of breed, lactation number, and month and year of calving on colostral specific gravity were determined, as were correlations between colostral specific gravity, nonlactating period length, and 305-d yields of milk, protein, and fat. For 75 multiparous Holstein cows, relationships between colostral specific gravity, colostral IgG1, protein, and fat concentrations, and season of calving were determined. Colostral specific gravity values were lower for Brown Swiss and Ayrshire cows than for Jersey and Holstein cows, and lower for cows entering first or second lactation than third or later lactations. Month of calving markedly affected colostral specific gravity values, with highest values occurring in autumn and lowest values in summer. In multiparous Holstein cows, colostral specific gravity was more strongly correlated with colostral protein concentration (r = 0.76) than IgG1 concentration (r = 0.53), and colostral protein concentration varied seasonally (higher in autumn than summer). Our results demonstrate that colostral specific gravity more closely reflects colostral protein concentration than IgG1 concentration and is markedly influenced by month of calving. These results highlight potential limitations of using colostral specific gravity as an indicator of IgG1 concentration. PMID:11352170

  3. Effects of roughness and compressibility of flooring on cow locomotion.

    PubMed

    Rushen, J; de Passillé, A M

    2006-08-01

    We examined the effects of roughness and degree of compressibility of flooring on the locomotion of dairy cows. We observed 16 cows walking down specially constructed walkways with materials that differed in surface roughness and degree of compressibility. Use of a commercially available soft rubber flooring material decreased slipping, number of strides, and time to traverse the corridor. These effects were most apparent at difficult sections of the corridor, such as at the start, at a right-angle turn, and across a gutter. Covering the walkway with a thin layer of slurry increased frequency of slipping, number of strides, and time taken to traverse the walkway. Effects of adding slurry were not overcome by increasing surface roughness or compressibility. Placing more compressible materials under a slip-resistant material reduced the time and number of steps needed to traverse the corridor but did not reduce slips, and the effects on cow locomotion varied nonlinearly with the degree of compressibility of the floor. Use of commercially available rubber floors improved cow locomotion compared with concrete floors. However, standard engineering measures of the floor properties may not predict effects of the floor on cow behavior well. Increasing compressibility of the flooring on which cows walk, independently of the roughness of the surface, can improve cow locomotion. PMID:16840611

  4. Assessing physiological complexity.

    PubMed

    Burggren, W W; Monticino, M G

    2005-09-01

    Physiologists both admire and fear complexity, but we have made relatively few attempts to understand it. Inherently complex systems are more difficult to study and less predictable. However, a deeper understanding of physiological systems can be achieved by modifying experimental design and analysis to account for complexity. We begin this essay with a tour of some mathematical views of complexity. After briefly exploring chaotic systems, information theory and emergent behavior, we reluctantly conclude that, while a mathematical view of complexity provides useful perspectives and some narrowly focused tools, there are too few generally practical take-home messages for physiologists studying complex systems. Consequently, we attempt to provide guidelines as to how complex systems might be best approached by physiologists. After describing complexity based on the sum of a physiological system's structures and processes, we highlight increasingly refined approaches based on the pattern of interactions between structures and processes. We then provide a series of examples illustrating how appreciating physiological complexity can improve physiological research, including choosing experimental models, guiding data collection, improving data interpretations and constructing more rigorous system models. Finally, we conclude with an invitation for physiologists, applied mathematicians and physicists to collaborate on describing, studying and learning from studies of physiological complexity. PMID:16109885

  5. Relationship between the milk yield response to short-term bovine somatotropin treatment and the lipolytic response to adrenaline in dairy cows.

    PubMed

    Rose, M T; Weekes, T E C; Rowlinson, P

    2009-01-01

    The aim of this experiment was to determine if the milk yield response of dairy cows to short-term treatment with bovine somatotropin (bST) was correlated with the non-esterified fatty-acid (NEFA) response to an adrenaline challenge. Twenty-six multiparous Holstein cows (58+/-5.4 days postpartum) received daily sub-cutaneous injections of saline for 7 days followed by sub-cutaneous injections of 20mg/day of bST for 14 days. On day 7 of the saline treatment and day 14 of the bST treatment the cows were given an intravenous injection of adrenaline (1.4 microg/kg body weight). Blood samples were taken before and after the adrenaline challenge. The difference in milk yield between the saline and the second week of bST treatment (MYR) varied considerably between animals (from -0.4 to +8.0 kg/day). MYR was positively correlated with the change in the basal concentration of NEFA between the saline and second week of bST treatment, as well as with the change in the area under the profile of NEFA above basal values following the adrenaline challenge. It remains to be established whether the greater lipolytic responses to adrenaline of the cows with the greater MYR reflects the deeper negative energy that these animals also experienced or a fundamental difference in the physiology of their adipose tissue. PMID:18952396

  6. Aetiology of reduced milk ejection in cows after transport and the use of a long-acting analogue of oxytocin for prophylaxis.

    PubMed

    Riedl, J; Daffner, B L; Kiossis, E; Bruckmaier, R M; Stolla, R

    2001-05-26

    Milk flow was recorded in 21 cows for three days after they were admitted to a large animal hospital. When the spontaneous flow of milk had stopped, a physiological dose (1 iu) of oxytocin was administered intravenously. Five of the cows were, in addition, treated with 0.35 mg of a long-acting analogue of oxytocin (carbetocin) one hour before the first milking after they were admitted. In the 16 cows not treated with carbetocin, only about 30 per cent of the total milk yield was released spontaneously on the first day, and the injection of 1 iu of oxytocin released approximately another 60 per cent of the total milk yield. On the second day, the proportion of the total milk yield released spontaneously increased and the fraction released after the injection of 1 iu oxytocin decreased. In contrast, the five cows treated with carbetocin released on average 94 per cent of the total milk yield spontaneously during the first milking. PMID:11400985

  7. Human physiology in space

    NASA Technical Reports Server (NTRS)

    Vernikos, J.

    1996-01-01

    The universality of gravity (1 g) in our daily lives makes it difficult to appreciate its importance in morphology and physiology. Bone and muscle support systems were created, cellular pumps developed, neurons organised and receptors and transducers of gravitational force to biologically relevant signals evolved under 1g gravity. Spaceflight provides the only microgravity environment where systematic experimentation can expand our basic understanding of gravitational physiology and perhaps provide new insights into normal physiology and disease processes. These include the surprising extent of our body's dependence on perceptual information, and understanding the effect and importance of forces generated within the body's weightbearing structures such as muscle and bones. Beyond this exciting prospect is the importance of this work towards opening the solar system for human exploration. Although both appear promising, we are only just beginning to taste what lies ahead.

  8. Index of thermal stress for cows (ITSC) under high solar radiation in tropical environments

    NASA Astrophysics Data System (ADS)

    Da Silva, Roberto Gomes; Maia, Alex Sandro C.; de Macedo Costa, Leonardo Lelis

    2015-05-01

    This paper presents a new thermal stress index for dairy cows in inter-tropical regions, with special mention to the semi-arid ones. Holstein cows were measured for rectal temperature ( T R), respiratory rate ( F R) and rates of heat exchange by convection ( C), radiation ( R), skin surface evaporation ( E S) and respiratory evaporation ( E R) in the north eastern region of Brazil, after exposure to sun for several hours. Average environmental measurements during the observations were air temperature ( T A) 32.4 °C (24.4-38.9°), wind speed ( U) 1.8 m.s-1 (0.01-11.0), relative humidity 63.6 % (36.8-81.5) and short-wave solar radiation 701.3 W m-2 (116-1,295). The effective radiant heat load (ERHL) was 838.5 ± 4.9 W m-2. Values for the atmospheric transmittance ( ?) were also determined for tropical regions, in order to permit adequate estimates of the solar radiation. The average value was ? = 0.611 ± 0.004 for clear days with some small moving clouds, with a range of 0.32 to 0.91 in the day period from 1000 to 1300 hours. Observed ? values were higher (0.62-0.66) for locations near the seacoast and in those regions well-provided with green fields. Effects of month, location and time of the day were all statistically significant ( P < 0.01). A total of 1,092 data were obtained for cows exposed for 1 to 8 h to sun during the day; in 7 months (February, March, April, July, August, September and November), 4 days per month on the average. A principal component analysis summarised the T R, F R, C, R, E S and E R measurements into just one synthetic variable ( y 1); several indexes were then obtained by multiple regression of y 1 on the four environmental variables and its combinations, by using Origin 8.1 software (OriginLab Corp.). The chosen equation was the index of thermal stress for cows, ITSC = 77.1747 + 4.8327 T A - 34.8189 U + 1.111 U 2 + 118.6981 P V - 14.7956 P V 2 - 0.1059 ERHL with r 2 = 0.812. The correlations of ITSC with T R, F R, C, E S, R and E R were 0.275, 0.255, -0.493, -0.647, -0.818 and 0.075, respectively. Correlations of the index with the physiological variables are presented, and ITSC is compared to three other indexes.

  9. Index of thermal stress for cows (ITSC) under high solar radiation in tropical environments.

    PubMed

    Da Silva, Roberto Gomes; Maia, Alex Sandro C; de Macedo Costa, Leonardo Lelis

    2015-05-01

    This paper presents a new thermal stress index for dairy cows in inter-tropical regions, with special mention to the semi-arid ones. Holstein cows were measured for rectal temperature (T R), respiratory rate (F R) and rates of heat exchange by convection (C), radiation (R), skin surface evaporation (E S) and respiratory evaporation (E R) in the north eastern region of Brazil, after exposure to sun for several hours. Average environmental measurements during the observations were air temperature (T A) 32.4 °C (24.4-38.9°), wind speed (U) 1.8 m.s(-1) (0.01-11.0), relative humidity 63.6 % (36.8-81.5) and short-wave solar radiation 701.3 W m(-2) (116-1,295). The effective radiant heat load (ERHL) was 838.5?±?4.9 W m(-2). Values for the atmospheric transmittance (?) were also determined for tropical regions, in order to permit adequate estimates of the solar radiation. The average value was ??=?0.611?±?0.004 for clear days with some small moving clouds, with a range of 0.32 to 0.91 in the day period from 1000 to 1300 hours. Observed ? values were higher (0.62-0.66) for locations near the seacoast and in those regions well-provided with green fields. Effects of month, location and time of the day were all statistically significant (P?cows exposed for 1 to 8 h to sun during the day; in 7 months (February, March, April, July, August, September and November), 4 days per month on the average. A principal component analysis summarised the T R, F R, C, R, E S and E R measurements into just one synthetic variable (y 1); several indexes were then obtained by multiple regression of y 1 on the four environmental variables and its combinations, by using Origin 8.1 software (OriginLab Corp.). The chosen equation was the index of thermal stress for cows, ITSC?=?77.1747?+?4.8327 T A?-?34.8189 U?+?1.111 U (2)?+?118.6981 P V?-?14.7956 P V (2)?-?0.1059 ERHL with r (2)?=?0.812. The correlations of ITSC with T R, F R, C, E S, R and E R were 0.275, 0.255, -0.493, -0.647, -0.818 and 0.075, respectively. Correlations of the index with the physiological variables are presented, and ITSC is compared to three other indexes. PMID:25085700

  10. Longitudinal Profiling of the Tissue-Specific Expression of Genes Related with Insulin Sensitivity in Dairy Cows during Lactation Focusing on Different Fat Depots

    PubMed Central

    Saremi, Behnam; Winand, Sarah; Friedrichs, Paula; Kinoshita, Asako; Rehage, Jürgen; Dänicke, Sven; Häussler, Susanne; Breves, Gerhard; Mielenz, Manfred; Sauerwein, Helga

    2014-01-01

    In dairy cows the milk associated energy output in early lactation exceeds the input via voluntary feed intake. To spare glucose for mammary lactose synthesis, peripheral insulin sensitivity (IS) is reduced and fat mobilization is stimulated. For these processes a link between IS and the endocrine functions of adipose tissue (AT) is likely; we thus aimed to characterise the mRNA expression from bovine AT derived proteins and receptors that are related to IS according to the literature in metabolically active tissues plus systemic IS throughout lactation. Conjugated linoleic acids (CLA) reduce milk fat thus decreasing the milk drain of energy and potentially dampening lipolysis, but may also affect IS. Subcutaneous (s.c.) AT and liver from pluriparous cows receiving either control fat or CLA supplement (100 g/day from 1 to 182 days in milk each) were biopsied covering week ?3 to 36 relative to parturition. In an additional trial with primiparous cows treated analogously and slaughtered on days in milk 1, 42 or 105, samples from liver, udder, skeletal muscle and 3 visceral and 3 s.c. AT were obtained and assayed for mRNA abundance of adiponectin, its receptors, leptin, leptin receptor, PPAR?, PPAR?2, IL-6, and TNF-?. In pluriparous animals, the mRNA abundance of most of the target genes decreased after parturition in s.c. AT but increased in liver. In primiparous cows, AT depot specific differences were mostly related to retroperitoneal AT; adiponectin receptor 1 and TNF-? were affected predominantly. CLA effects in primiparous cows were largely limited to decreased PPAR?2 mRNA abundance in udder tissue. In pluriparous cows, insulin secretion was increased by CLA resulting in decreased systemic IS but without consistent changes in tissue target mRNA abundance. The temporal gene expression profiles from the adipokines and related receptors support their coactive function in adapting to the needs of lactation. PMID:24465964

  11. Effects of weightlessness on human fluid and electrolyte physiology

    NASA Technical Reports Server (NTRS)

    Leach, Carolyn S.; Johnson, Philip C., Jr.

    1991-01-01

    Skylab and Spacelab data on changes occurring in human fluid and electrolyte physiology during the acute and adaptive phases of adaptation to spaceflight are summarized. The combined results for all three Spacelab studies show that hyponatremia developed within 20 h after the onset of weightlessness and continued throughout the flights, and hypokalemia developed by 40 h. Antidiuretic hormone was increased in plasma throughout the flights. Aldosterone decreased by 40 h, but after 7 days it had reached preflight levels.

  12. Fertilization and early embryonic development in heifers and lactating cows in summer and lactating and dry cows in winter.

    PubMed

    Sartori, R; Sartor-Bergfelt, R; Mertens, S A; Guenther, J N; Parrish, J J; Wiltbank, M C

    2002-11-01

    Two experiments in two seasons evaluated fertilization rate and embryonic development in dairy cattle. Experiment 1 (summer) compared lactating Holstein cows (n = 27; 97.3 +/- 4.1 d postpartum [dppl; 40.0 +/- 1.5 kg milk/d) to nulliparous heifers (n = 28; 11 to 17 mo old). Experiment 2 (winter) compared lactating cows (n = 27; 46.4 +/- 1.6 dpp; 45.9 +/- 1.4 kg milk/d) to dry cows (n = 26). Inseminations based on estrus included combined semen from four high-fertility bulls. Embryos and oocytes recovered 5 d after ovulation were evaluated for fertilization, embryo quality (1 = excellent to 5 = degenerate), nuclei/embryo, and accessory sperm. In experiment 1, 21 embryos and 17 unfertilized oocytes (UFO) were recovered from lactating cows versus 32 embryos and no UFO from heifers (55% vs. 100% fertilization). Embryos from lactating cows had inferior quality scores (3.8 +/- 0.4 vs. 2.2 +/- 0.3), fewer nuclei/embryo (19.3 +/- 3.7 vs. 36.8 +/- 3.0) but more accessory sperm (37.3 +/- 5.8 vs. 22.4 +/- 5.5/embryo) than embryos from heifers. Sperm were attached to 80% of UFO (17.8 +/- 12.1 sperm/UFO). In experiment 2, lactating cows yielded 36 embryos and 5 UFO versus 34 embryos and 4 UFO from dry cows (87.8 vs. 89.5% fertilization). Embryo quality from lactating cows was inferior to dry cows (3.1 +/- 0.3 vs. 2.2 +/- 0.3), but embryos had similar numbers of nuclei (27.2 +/- 2.7 vs. 30.6 +/- 2.1) and accessory sperm (42.0 +/- 9.4 vs. 36.5 +/- 6.3). From 53% of the flushings from lactating cows and 28% from dry cows, only nonviable embryos were collected. Thus, embryos of lactating dairy cows were detectably inferior to embryos from nonlactating females as early as 5 d after ovulation, with a surprisingly high percentage of nonviable embryos. In addition, fertilization rate was reduced only in summer, apparently due to an effect of heat stress on the oocyte. PMID:12487447

  13. Effects of dietary Capsicum oleoresin on productivity and immune responses in lactating dairy cows.

    PubMed

    Oh, J; Giallongo, F; Frederick, T; Pate, J; Walusimbi, S; Elias, R J; Wall, E H; Bravo, D; Hristov, A N

    2015-09-01

    This study investigated the effect of Capsicum oleoresin in granular form (CAP) on nutrient digestibility, immune responses, oxidative stress markers, blood chemistry, rumen fermentation, rumen bacterial populations, and productivity of lactating dairy cows. Eight multiparous Holstein cows, including 3 ruminally cannulated, were used in a replicated 4×4 Latin square design experiment. Experimental periods were 25 d in duration, including a 14-d adaptation and an 11-d data collection and sampling period. Treatments included control (no CAP) and daily supplementation of 250, 500, or 1,000 mg of CAP/cow. Dry matter intake was not affected by CAP (average 27.0±0.64 kg/d), but milk yield tended to quadratically increase with CAP supplementation (50.3 to 51.9±0.86 kg/d). Capsicum oleoresin quadratically increased energy-corrected milk yield, but had no effect on milk fat concentration. Rumen fermentation variables, apparent total-tract digestibility of nutrients, and N excretion in feces and urine were not affected by CAP. Blood serum ?-hydroxybutyrate was quadratically increased by CAP, whereas the concentration of nonesterified fatty acids was similar among treatments. Rumen populations of Bacteroidales, Prevotella, and Roseburia decreased and Butyrivibrio increased quadratically with CAP supplementation. T cell phenotypes were not affected by treatment. Mean fluorescence intensity for phagocytic activity of neutrophils tended to be quadratically increased by CAP. Numbers of neutrophils and eosinophils and the ratio of neutrophils to lymphocytes in peripheral blood linearly increased with increasing CAP. Oxidative stress markers were not affected by CAP. Overall, in the conditions of this experiment, CAP did not affect feed intake, rumen fermentation, nutrient digestibility, T cell phenotypes, and oxidative stress markers. However, energy-corrected milk yield was quadratically increased by CAP, possibly as a result of enhanced mobilization of body fat reserves. In addition, CAP increased neutrophil activity and immune cells related to acute phase immune response. PMID:26188565

  14. Effect of feeding rumen protected rice bran on calcium homeostasis of non-lactating multiparous cows.

    PubMed

    Martín-Tereso, J; van Puijenbroek, R; van Vuuren, A M; van Laar, H; den Hartog, L A; Verstegen, M W A

    2011-04-01

    Milk fever in dairy cows can be prevented by activating Ca homeostasis before calving. Homeostatic adaptation can be achieved by reducing dietary Ca availability. Formaldehyde-treated rice bran was studied to supply rumen protected phytic acid to reduce Ca availability. Twelve multiparous dry cows were used in a 3×3 Latin square change-over design with 5-day periods to test three dietary treatments. Diets consisted of a forage mix (maize silage, grass silage and hay), being 77% of ration dry matter, supplemented with three concentrates: Control (no formaldehyde-treated rice bran), T1 (100% formaldehyde-treated rice bran) and T2 (99.5% formaldehyde-treated rice bran with 0.6% Ca carbonate, to equal Ca content of Control). Dietary treatments did not affect urine pH (8.14, 8.13 and 8.11 for Control, T1 and T2 respectively) or dry matter intake (13.9, 13.7 and 13.8 kg for Control, T1 and T2 respectively). Including formaldehyde-treated rice bran in the diet resulted in lower urinary Ca/creatinine ratio (0.970, 0.457 and 0.618 for Control, T1 and T2 respectively). A sudden increase of urinary Ca excretion took place after withdrawal of T1 and T2 at introduction of Control, peaking on the first day and coming back down progressively in the second and third days. Peak was greatest after T1 and was not observed in transitions between rice bran treatments. This is understood as indirect evidence of activation of intestinal Ca absorption during formaldehyde-treated rice bran feeding, because renal adaptations to changes in blood Ca clearance are immediate and intestinal adaptations delay 2 days. It was concluded that including formaldehyde-treated rice bran in rations before calving may represent a dietary strategy to prevent milk fever without reducing dry matter intake. PMID:20796076

  15. Bacteria recovered from endometritis and pyometra in the beef cow 

    E-print Network

    Mikulec, Rashel Thi

    1999-01-01

    One hundred and one uteri from beef cows with pyometra were collected from a slaughterhouse. Samples of uterine exudate were cultured for aerobic, microaerophilic, and anaerobic bacteria, and also tested for Trichomonas spp. A section of uterine...

  16. Bovine Spongiform Encephalopathy (BSE), or Mad Cow Disease

    MedlinePLUS

    ... spongiform encephalopathy) is a progressive neurological disorder of cattle that results from infection by an unusual transmissible ... that then damages the central nervous system of cattle. More Mad Cow Disease is a neurological disorder ...

  17. Body Condition, Nutrition and Reproduction of Beef Cows 

    E-print Network

    Herd, Dennis B.; Sprott, L. R.

    1998-03-16

    Producers must be able to evaluate beef cows' body reserves and to relate the evaluation to reproductive and nutritional management. Topics discussed include the practical importance of body condition scoring and various BCS suggestions....

  18. Fall and Winter Health Problems in Cow-Calf Herds 

    E-print Network

    Faries Jr., Floron C.

    2005-09-09

    Producers can prevent or minimize health problems in cow-calf herds in fall and winter by reducing the stresses caused by inadequate nutrition, sudden feeding changes and unsanitary conditions. This publication describes common health problems...

  19. Evolutionary plant physiology: Charles Darwin's forgotten synthesis

    NASA Astrophysics Data System (ADS)

    Kutschera, Ulrich; Niklas, Karl J.

    2009-11-01

    Charles Darwin dedicated more than 20 years of his life to a variety of investigations on higher plants (angiosperms). It has been implicitly assumed that these studies in the fields of descriptive botany and experimental plant physiology were carried out to corroborate his principle of descent with modification. However, Darwin’s son Francis, who was a professional plant biologist, pointed out that the interests of his father were both of a physiological and an evolutionary nature. In this article, we describe Darwin’s work on the physiology of higher plants from a modern perspective, with reference to the following topics: circumnutations, tropisms and the endogenous oscillator model; the evolutionary patterns of auxin action; the root-brain hypothesis; phloem structure and photosynthesis research; endosymbioses and growth-promoting bacteria; photomorphogenesis and phenotypic plasticity; basal metabolic rate, the Pfeffer-Kleiber relationship and metabolic optimality theory with respect to adaptive evolution; and developmental constraints versus functional equivalence in relationship to directional natural selection. Based on a review of these various fields of inquiry, we deduce the existence of a Darwinian (evolutionary) approach to plant physiology and define this emerging scientific discipline as the experimental study and theoretical analysis of the functions of green, sessile organisms from a phylogenetic perspective.

  20. Programmable physiological infusion

    NASA Technical Reports Server (NTRS)

    Howard, W. H.; Young, D. R.; Adachi, R. R. (inventors)

    1974-01-01

    A programmable physiological infusion device and method are provided wherein a program source, such as a paper tape, is used to actuate an infusion pump in accordance with a desired program. The system is particularly applicable for dispensing calcium in a variety of waveforms.

  1. Post-Harvest Physiology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Numerous plant microbial and physiological processes occur during forage harvest and storage and are almost always deleterious. These processes are influenced by preharvest factors such as mowing time of day, plant species, and maturity stage, as well as by harvest and storage variables. Avoidance o...

  2. Starting Physiology: Bioelectrogenesis

    ERIC Educational Resources Information Center

    Baptista, Vander

    2015-01-01

    From a Cartesian perspective of rational analysis, the electric potential difference across the cell membrane is one of the fundamental concepts for the study of physiology. Unfortunately, undergraduate students often struggle to understand the genesis of this energy gradient, which makes the teaching activity a hard task for the instructor. The…

  3. Alien Physiology, Convergent Evolution,

    E-print Network

    Walter, Frederick M.

    Alien Physiology, Convergent Evolution, and fc #12;N = N* fs fGHZ fp nH fl fJ ffEufm fi fc L/T ·N Intelligent Aliens be Humanoids? #12;What might a Martian look like? Let's build an alien... #12;If we expect

  4. COFFEE SEED PHYSIOLOGY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are more than 70 species of Coffea (Rubiaceae), but only C. arabica and C. canephora are used commercially. Better understanding of seed physiology within Coffea will facilitate the incorporation of genetic traits for resistance to biotic and abiotic stresses from wild relatives into commerci...

  5. Psychology 260 Physiological Psychology

    E-print Network

    Gallo, Linda C.

    Psychology 260 Physiological Psychology Instructor: Amy Spilkin, Ph.D. Office Hours: Before and after class and by appointment Location: LS-24C Phone: 858-822-6800 Email: aspilkin@crl.ucsd.edu (please allow 24 hours for response) Required Prerequisite: Psychology 101 and Biology 100 Materials: Kalat

  6. Simulated Exercise Physiology Laboratories.

    ERIC Educational Resources Information Center

    Morrow, James R., Jr.; Pivarnik, James M.

    This book consists of a lab manual and computer disks for either Apple or IBM hardware. The lab manual serves as "tour guide" for the learner going through the various lab experiences. The manual contains definitions, proper terminology, and other basic information about physiological principles. It is organized so a step-by-step procedure may be…

  7. Physiology in microgravity.

    PubMed

    West, J B

    2000-07-01

    Studies of physiology in microgravity are remarkably recent, with almost all the data being obtained in the past 40 years. The first human spaceflight did not take place until 1961. Physiological measurements in connection with the early flights were crude, but, in the past 10 years, an enormous amount of new information has been obtained from experiments on Spacelab. The United States and Soviet/Russian programs have pursued different routes. The US has mainly concentrated on relatively short flights but with highly sophisticated equipment such as is available in Spacelab. In contrast, the Soviet/Russian program concentrated on first the Salyut and then the Mir space stations. These had the advantage of providing information about long-term exposure to microgravity, but the degree of sophistication of the measurements in space was less. It is hoped that the International Space Station will combine the best of both approaches. The most important physiological changes caused by microgravity include bone demineralization, skeletal muscle atrophy, vestibular problems causing space motion sickness, cardiovascular problems resulting in postflight orthostatic intolerance, and reductions in plasma volume and red cell mass. Pulmonary function is greatly altered but apparently not seriously impaired. Space exploration is a new frontier with long-term missions to the moon and Mars not far away. Understanding the physiological changes caused by long-duration microgravity remains a daunting challenge. PMID:10904075

  8. Physiology of Breastfeeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This powerpoint presentation summaries physiology of lactation and the impact of a variety of clinical practices on lactation from delivery through weaning. Factors that inhibit lactogenesis stage II are explained, including retained placenta, excess blood loss during delivery, and hypoplastic brea...

  9. Renal Physiology of Pregnancy

    PubMed Central

    Cheung, Katharine L.; Lafayette, Richard A.

    2014-01-01

    Pregnancy involves remarkable orchestration of physiologic changes. The kidneys are central players in the evolving hormonal milieu of pregnancy, responding and contributing to the changes in the environment for the pregnant woman and fetus. The functional impact of pregnancy on kidney physiology is widespread, involving practically all aspects of kidney function. The glomerular filtration rate increases 50% with subsequent decrease in serum creatinine, urea, and uric acid values. The threshold for thirst and antidiuretic hormone secretion are depressed, resulting in lower osmolality and serum sodium levels. Blood pressure drops approximately 10 mmHg by the second trimester despite a gain in intravascular volume of 30% to 50%. The drop in systemic vascular resistance is multifactorial, attributed in part to insensitivity to vasoactive hormones, and leads to activation of the renin-aldosterone-angiostensin system. A rise in serum aldosterone results in a net gain of approximately 1000 mg of sodium. A parallel rise in progesterone protects the pregnant woman from hypokalemia. The kidneys increase in length and volume, and physiologic hydronephrosis occurs in up to 80% of women. This review will provide an understanding of these important changes in kidney physiology during pregnancy, which is fundamental in caring for the pregnant patient. PMID:23928384

  10. The Physiology of Motivation.

    ERIC Educational Resources Information Center

    Stellar, Eliot

    1994-01-01

    A theory of the physiology of motivation is presented. The basic assumption is that the amount of motivated behavior is a direct function of the amount of activity in certain excitatory centers of the hypothalamus. Activities of these centers are determined by factors in four general classes. (SLD)

  11. Body Condition, Nutrition and Reproduction of Beef Cows

    E-print Network

    Herd, Dennis B.; Sprott, L.R.

    1986-01-01

    not accurately reflect changes in nutritional statu~. In winter feeding studies where live weight and body condition scores have been measured, body condition commonly decreases proportionally more than live weight, implying a greater loss of energy relative... and internal parasites may be involved. A combination of these nutritional problems is fre quently observed. In a commercial cow-calf program, the digestible energy requirement of the cow and calf should come from forage produced on the operator's farm...

  12. Avian reproductive physiology

    USGS Publications Warehouse

    Gee, G.F.

    1995-01-01

    Knowledge of the many physiological factors associated with egg production , fertility, incubation, and brooding in nondomestic birds is limited. Science knows even less about reproduction in most of the 238 endangered or threatened birds. This discussion uses studies of nondomestic and, when necessary, domestic birds to describe physiological control of reproduction. Studies of the few nondomestic avian species show large variation in physiological control of reproduction. Aviculturists, in order to successfully propagate an endangered bird, must understand the bird's reproductive peculiarities. First, investigators can do studies with carefully chosen surrogate species, but eventually they need to confirm the results in the target endangered bird. Studies of reproduction in nondomestic birds increased in the last decade. Still, scientists need to do more comparative studies to understand the mechanisms that control reproduction in birds. New technologies are making it possible to study reproductive physiology of nondomestic species in less limiting ways. These technologies include telemetry to collect information without inducing stress on captives (Howey et al., 1987; Klugman, 1987), new tests for most of the humoral factors associated with reproduction, and the skill to collect small samples and manipulate birds without disrupting the physiological mechanisms (Bercovitz et al., 1985). Managers are using knowledge from these studies to improve propagation in zoological parks, private and public propagation facilities, and research institutions. Researchers need to study the control of ovulation, egg formation, and oviposition in the species of nondomestic birds that lay very few eggs in a season, hold eggs in the oviduct for longer intervals, or differ in other ways from the more thoroughly studied domestic birds. Other techniques that would enhance propagation for nondomestlc birds include tissue culture of cloned embryonic cells, cryopreservation of embryos and gametes, embryo transplant, DNA analysis and manipulation, disease screening and control, and improved release conditioning methods.

  13. Physiological attributes of triathletes.

    PubMed

    Suriano, R; Bishop, D

    2010-05-01

    Triathlons of all distances can be considered endurance events and consist of the individual disciplines of swimming, cycling and running which are generally completed in this sequential order. While it is expected that elite triathletes would possess high values for submaximal and maximal measures of aerobic fitness, little is known about how these values compare with those of single-sport endurance athletes. Earlier reviews, conducted in the 1980s, concluded that triathletes possessed lower V(O2(max)) values than other endurance athletes. An update of comparisons is of interest to determine if the physiological capacities of elite triathletes now reflect those of single-sport athletes or whether these physiological capacities are compromised by the requirement to cross-train for three different disciplines. It was found that although differences in the physiological attributes during swimming, cycling and running are evident among triathletes, those who compete at an international level possess V(O2(max)) values that are indicative of success in endurance-based individual sports. Furthermore, various physiological parameters at submaximal workloads have been used to describe the capacities of these athletes. Only a few studies have reported the lactate threshold among triathletes with the majority of studies reporting the ventilatory threshold. Although observed differences among triathletes for both these submaximal measures are complicated by the various methods used to determine them, the reported values for triathletes are similar to those for trained cyclists and runners. Thus, from the limited data available, it appears that triathletes are able to obtain similar physiological values as single-sport athletes despite dividing their training time among three disciplines. PMID:19577959

  14. Differences in peripartal plasma parameters related to calcium homeostasis of dairy sheep and goats in comparison with cows.

    PubMed

    Wilkens, Mirja R; Liesegang, Annette; Richter, Julia; Fraser, David R; Breves, Gerhard; Schröder, Bernd

    2014-08-01

    Recently it has been demonstrated that there are differences between sheep and goats in respect to adaptation to a calcium-restricted diet. It was the aim of the present study to evaluate whether species-specific peculiarities also occur when calcium homoeostasis is challenged by lactation. Therefore, we investigated the time courses of plasma parameters related to calcium homoeostasis (calcium, phosphate, calcitriol, the bone resorption marker CrossLaps and the bone formation marker osteocalcin) during the transition period in multiparous animals of both species and compared the results to data from a former study carried out with dairy cows. As in cows, plasma calcium and the ratio of bone formation to bone resorption decreased at parturition in goats while plasma calcitriol increased. On day 10 post partum the bone parameters of goats reached prepartum values again, which was not the case in cows. Sheep were found to experience a challenge of calcium homoeostasis already 10 d before parturition, reflected by a very low ratio of bone formation to bone resorption, which was not accompanied by an increase in plasma calcitriol. Additionally, sheep and goats which had been in milk for 3 months were sampled, dried-off and sampled again 6 weeks later. In dried-off animals there were no detectable differences in parameters of bone metabolism. In conclusion we could show that the contribution of bone mobilisation to the compensation for the enhanced calcium demand due to lactation differs between the three ruminant species. PMID:24871571

  15. Effects of nitrogen fertilisation rate and maturity of grass silage on methane emission by lactating dairy cows.

    PubMed

    Warner, D; Hatew, B; Podesta, S C; Klop, G; van Gastelen, S; van Laar, H; Dijkstra, J; Bannink, A

    2016-01-01

    Grass silage is typically fed to dairy cows in temperate regions. However, in vivo information on methane (CH4) emission from grass silage of varying quality is limited. We evaluated the effect of two rates of nitrogen (N) fertilisation of grassland (low fertilisation (LF), 65 kg of N/ha; and high fertilisation (HF), 150 kg of N/ha) and of three stages of maturity of grass at cutting: early maturity (EM; 28 days of regrowth), mid maturity (MM; 41 days of regrowth) and late maturity (LM; 62 days of regrowth) on CH4 production by lactating dairy cows. In a randomised block design, 54 lactating Holstein-Friesian dairy cows (168±11 days in milk; mean±standard error of mean) received grass silage (mainly ryegrass) and compound feed at 80 : 20 on dry matter basis. Cows were adapted to the diet for 12 days and CH4 production was measured in climate respiration chambers for 5 days. Dry matter intake (DMI; 14.9±0.56 kg/day) decreased with increasing N fertilisation and grass maturity. Production of fat- and protein-corrected milk (FPCM; 24.0±1.57 kg/day) decreased with advancing grass maturity but was not affected by N fertilisation. Apparent total-tract feed digestibility decreased with advancing grass maturity but was unaffected by N fertilisation except for an increase and decrease in N and fat digestibility with increasing N fertilisation, respectively. Total CH4 production per cow (347±13.6 g/day) decreased with increasing N fertilisation by 4% and grass maturity by 6%. The smaller CH4 production with advancing grass maturity was offset by a smaller FPCM and lower feed digestibility. As a result, with advancing grass maturity CH4 emission intensity increased per units of FPCM (15.0±1.00 g CH4/kg) by 31% and digestible organic matter intake (33.1±0.78 g CH4/kg) by 15%. In addition, emission intensity increased per units of DMI (23.5±0.43 g CH4/kg) by 7% and gross energy intake (7.0±0.14% CH4) by 9%, implying an increased loss of dietary energy with advancing grass maturity. Rate of N fertilisation had no effect on CH4 emissions per units of FPCM, DMI and gross energy intake. These results suggest that despite a lower absolute daily CH4 production with a higher N fertilisation rate, CH4 emission intensity remains unchanged. A significant reduction of CH4 emission intensity can be achieved by feeding dairy cows silage of grass harvested at an earlier stage of maturity. PMID:26264354

  16. Effect of Feeding Bacillus subtilis natto on Hindgut Fermentation and Microbiota of Holstein Dairy Cows

    PubMed Central

    Song, D. J.; Kang, H. Y.; Wang, J. Q.; Peng, H.; Bu, D. P.

    2014-01-01

    The effect of Bacillus subtilis natto on hindgut fermentation and microbiota of early lactation Holstein dairy cows was investigated in this study. Thirty-six Holstein dairy cows in early lactation were randomly allocated to three groups: no B. subtilis natto as the control group, B. subtilis natto with 0.5×1011 cfu as DMF1 group and B. subtilis natto with 1.0×1011 cfu as DMF2 group. After 14 days of adaptation period, the formal experiment was started and lasted for 63 days. Fecal samples were collected directly from the rectum of each animal on the morning at the end of eighth week and placed into sterile plastic bags. The pH, NH3-N and VFA concentration were determined and fecal bacteria DNA was extracted and analyzed by DGGE. The results showed that the addition of B. subtilus natto at either treatment level resulted in a decrease in fecal NH3-N concentration but had no effect on fecal pH and VFA. The DGGE profile revealed that B. subtilis natto affected the population of fecal bacteria. The diversity index of Shannon-Wiener in DFM1 decreased significantly compared to the control. Fecal Alistipes sp., Clostridium sp., Roseospira sp., beta proteobacterium were decreased and Bifidobacterium was increased after supplementing with B. subtilis natto. This study demonstrated that B. subtilis natto had a tendency to change fecal microbiota balance. PMID:25049979

  17. Water salinity effects on performance and rumen parameters of lactating grazing Holstein cows

    NASA Astrophysics Data System (ADS)

    Valtorta, Silvia E.; Gallardo, Miriam R.; Sbodio, Oscar A.; Revelli, Germán R.; Arakaki, Cristina; Leva, Perla E.; Gaggiotti, Mónica; Tercero, Esteban J.

    2008-01-01

    Eighteen multiparous lactating grazing Holstein cows, 9 ruminally cannulated, average 136.1 ± 14.6 days in milk, were randomly assigned to three treatments consisting of water containing different levels of total dissolved solids (TDS; mg/l): Treatment 1 = 1,000; Treatment 2 = 5,000 and Treatment 3 = 10,000, at the Experimental Dairy Unit at Rafaela Experimental Station (31°11'S latitude) during summer 2005. Animals were arranged in a randomized complete block design with three 28-day experimental periods, with 3 weeks for water adaptation and 1 week for measurements. Feed and water intake, milk production and composition, body weight and condition score and rumen parameters were evaluated. No treatment effects were observed in any of the variables evaluated, with the exception of water intake, which was higher for animals receiving 10,000 mg/l TDS in the drinking water (189 l/day vs. 106 and 122 l/day for cows receiving water with 1,000 and 5,000 mg/l TDS, respectively). Water intake was significantly higher for animals in treatment 10,000 ( P < 0.05). It was concluded that the rumen presents a surprising buffer capacity and that consideration of TDS alone is insufficient to characterize drinking water quality.

  18. Effect of Feeding Bacillus subtilis natto on Hindgut Fermentation and Microbiota of Holstein Dairy Cows.

    PubMed

    Song, D J; Kang, H Y; Wang, J Q; Peng, H; Bu, D P

    2014-04-01

    The effect of Bacillus subtilis natto on hindgut fermentation and microbiota of early lactation Holstein dairy cows was investigated in this study. Thirty-six Holstein dairy cows in early lactation were randomly allocated to three groups: no B. subtilis natto as the control group, B. subtilis natto with 0.5×10(11) cfu as DMF1 group and B. subtilis natto with 1.0×10(11) cfu as DMF2 group. After 14 days of adaptation period, the formal experiment was started and lasted for 63 days. Fecal samples were collected directly from the rectum of each animal on the morning at the end of eighth week and placed into sterile plastic bags. The pH, NH3-N and VFA concentration were determined and fecal bacteria DNA was extracted and analyzed by DGGE. The results showed that the addition of B. subtilus natto at either treatment level resulted in a decrease in fecal NH3-N concentration but had no effect on fecal pH and VFA. The DGGE profile revealed that B. subtilis natto affected the population of fecal bacteria. The diversity index of Shannon-Wiener in DFM1 decreased significantly compared to the control. Fecal Alistipes sp., Clostridium sp., Roseospira sp., beta proteobacterium were decreased and Bifidobacterium was increased after supplementing with B. subtilis natto. This study demonstrated that B. subtilis natto had a tendency to change fecal microbiota balance. PMID:25049979

  19. How to Do It. Plant Eco-Physiology: Experiments on Crassulacean Acid Metabolism, Using Minimal Equipment.

    ERIC Educational Resources Information Center

    Friend, Douglas J. C.

    1990-01-01

    Features of Crassulacean Acid Metabolism plants are presented. Investigations of a complex eco-physiological plant adaptation to the problems of growth in an arid environment are discussed. Materials and procedures for these investigations are described. (CW)

  20. Recent advances in exploring physiology and biodiversity of ectomycorrhizas highlight the functioning of these symbioses

    E-print Network

    Recent advances in exploring physiology and biodiversity of ectomycorrhizas highlight 2000 Abstract Ectomycorrhizas, the dominating mycorrhizal symbiosis in boreal, temperate and some on such laboratory results, the adaptative capability of ectomycorrhizas to changing field conditions is discussed

  1. A Physiologically-based Model for Methylmercury Uptake and Accumulation in Female American Kestrels

    EPA Science Inventory

    A physiologically-based model was developed to describe the uptake, distribution, and elimination of methylmercury in female American Kestrels (Falco sparverius). The model was adapted from established models for methylmercury in rodents. Features unique to the model include meth...

  2. Plasma ceramides are elevated in overweight Holstein dairy cows experiencing greater lipolysis and insulin resistance during the transition from late pregnancy to early lactation.

    PubMed

    Rico, J E; Bandaru, V V R; Dorskind, J M; Haughey, N J; McFadden, J W

    2015-11-01

    Insulin resistance is a homeorhetic adaptation to parturition in dairy cows transitioning from late pregnancy to early lactation. An increase in prepartum adiposity can predispose periparturient cows to greater lipolysis and insulin resistance, thus increasing the risk for metabolic disease. Mechanisms mediating the development of insulin resistance in overweight peripartal dairy cows may depend on ceramide metabolism. The sphingolipid ceramide accumulates in plasma and tissues of overweight monogastric animals, and facilitates saturated fatty acid-induced insulin resistance. Considering this evidence, we hypothesized that plasma ceramides would be elevated in periparturient dairy cattle and that these sphingolipids would correlate with the magnitude of lipolysis and insulin resistance. To test our central hypothesis, multiparous Holstein cows were allocated into 2 groups according to their body condition score (BCS) at d -30 prepartum: lean (BCS <3.0; n=10) or overweight (BCS >4.0; n=11). Blood samples were collected at d -45, -30, -15, and -7, relative to expected parturition, and at d 4 postpartum. Plasma glucose, insulin, nonesterified fatty acids (NEFA), and ?-hydroxybutyrate (BHBA) concentrations were measured, and insulin sensitivity was estimated. The concentrations of individual plasma ceramide and glycosylated ceramide were determined using liquid chromatography-based mass spectrometry. Results demonstrated that greater adiposity was associated with a greater loss in body condition during late pregnancy. Overweight cows had greater circulating concentrations of glucose, insulin, and NEFA, and lower insulin sensitivity relative to lean cows. We detected 30 different sphingolipids across 6 lipid classes with acyl chains ranging from 16 to 26 carbons. The most abundant plasma sphingolipids detected were C24:0-ceramide, C24:0-monohexosylceramide, and C16:0-lactosylceramide. Plasma concentrations of total ceramide and monohexosylceramide increased as lactation approached, and saturated ceramide and monohexosylceramide were elevated in cows with greater adiposity relative to those with a lean phenotype. Plasma ceramides (e.g., C24:0-ceramide) were positively correlated with plasma NEFA and inversely correlated with insulin sensitivity. Our data demonstrate a remodeled plasma sphingolipidome in dairy cows transitioning from late pregnancy to lactation characterized by a concomitant increase in plasma ceramides with the development of peripartal insulin resistance. PMID:26342987

  3. Physiology and psychology of dreams.

    PubMed

    Eiser, Alan S

    2005-03-01

    The discovery of the close association between rapid eye movement (REM) sleep and dreaming and development of sleep laboratory techniques ushered in a new era in the study of dreams. For the first time, direct and systematic investigation could be made of such topics as the occurrence, qualities, recollection, and childhood development of dreaming. Experimental methodologies permitted investigation of the responsiveness of dreams to external stimulation and the effects of deprivation of REM sleep. Much effort was devoted to searching for parallels between physiological aspects of REM sleep and characteristics of associated dreams, with modest results. The leading theory of dreaming in the early decades of this research was the psychoanalytic, which views dreams as highly meaningful reflections of unconscious mental functioning. With developments in understanding of the neurophysiology of REM sleep, new theories of dreaming were proposed. The most prominent, the activation-synthesis hypothesis, derived its view of dreaming directly from the neurophysiology of REM sleep, in particular the role of the brain stem, and in its original form regarded dreams as not essentially meaningful. Further developments in neurobiological research, including lesion and brain imaging studies, have established a clearer view of the functional neuroanatomy of REM sleep and dreaming. To what degree, and in what way, implications can be drawn from these findings for the psychology of dreaming is controversial. Some more recent theories of dreaming emphasize an adaptive function related to emotion and a role in learning and memory consolidation. PMID:15798942

  4. Physiology of prolonged bed rest

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.

    1988-01-01

    Bed rest has been a normal procedure used by physicians for centuries in the treatment of injury and disease. Exposure of patients to prolonged bed rest in the horizontal position induces adaptive deconditioning responses. While deconditioning responses are appropriate for patients or test subjects in the horizontal position, they usually result in adverse physiological responses (fainting, muscular weakness) when the patient assume the upright posture. These deconditioning responses result from reduction in hydrostatic pressure within the cardiovascular system, virtual elimination of longitudinal pressure on the long bones, some decrease in total body metabolism, changes in diet, and perhaps psychological impact from the different environment. Almost every system in the body is affected. An early stimulus is the cephalic shift of fluid from the legs which increases atrial pressure and induces compensatory responses for fluid and electrolyte redistribution. Without countermeasures, deterioration in strength and muscle function occurs within 1 wk while increased calcium loss may continue for months. Research should also focus on drug and carbohydrate metabolism.

  5. Clinical physiology of bed rest

    NASA Technical Reports Server (NTRS)

    Greenleaf, John E.

    1993-01-01

    Maintenance of optimal health in humans requires the proper balance between exercise, rest, and sleep as well as time in the upright position. About one-third of a lifetime is spent sleeping; and it is no coincidence that sleeping is performed in the horizontal position, the position in which gravitational influence on the body is minimal. Although enforced bed rest is necessary for the treatment of some ailments, in some cases it has probably been used unwisely. In addition to the lower hydrostatic pressure with the normally dependent regions of the cardiovascular system, body fuid compartments during bed rest in the horizontal body position, and virtual elimination of compression on the long bones of the skeletal system during bed rest (hypogravia), there is often reduction in energy metabolism due to the relative confinement (hypodynamia) and alteration of ambulatory circadian variations in metabolism, body temperature, and many hormonal systems. If patients are also moved to unfamiliar surroundings, they probably experience some feelings of anxiety and some sociopsychological problems. Adaptive physiological responses during bed rest are normal for that environment. They are attempts by the body to reduce unnecessary energy expenditure, to optimize its function, and to enhance its survival potential. Many of the deconditioning responses begin within the first day or two of bed rest; these early responses have prompted physicians to insist upon early resumption of the upright posture and ambulation of bedridden patients.

  6. Ageing and physiological functions.

    PubMed Central

    Young, A

    1997-01-01

    In youth, most physiological functions have generous spare capacity. Even in health, however, increasing age is characterized by progressive erosion of these 'safety margins'. Examples include the decline of bone mass (towards a threshold for likelihood of fracture), of glomerular filtration rate (towards a threshold for susceptibility to clinical renal failure), of renal tubular function (towards a threshold for clinically important susceptibility to dehydration), of hepatic function (towards a threshold for accumulation following conventional 'young adult' doses of common medications), or of lower limb explosive power (towards thresholds for impaired functional mobility). Increasing age is also characterized by a rising prevalence of chronic pathologies, complicating attempts to determine the rate or the mechanism of the age-related decline in a physiological function. Nevertheless, it is clear that in many organs the loss of function is largely attributable to the loss of functioning cells, even in the absence of overt disease. This apparently fundamental aspect of ageing remains poorly understood. PMID:9460068

  7. Physiological and psychological stress limits for astronautics Observations during the Skylab I-III missions

    NASA Technical Reports Server (NTRS)

    Burchard, E. C.

    1975-01-01

    The physiological and psychological factors of manned space flight had a particular significance in the Skylab missions during which astronauts were subjected to a life in a space environment for longer periods of time than on previous space missions. The Skylab missions demonstrated again the great adaptability of human physiology to the environment of man. The results of Skylab have indicated also approaches for enhancing the capability of man to tolerate the physiological and psychological stresses of space flight.

  8. Pavlov and integrative physiology.

    PubMed

    Smith, G P

    2000-09-01

    Ivan Petrovich Pavlov was the first physiologist to win the Nobel Prize. The Prize was given in 1904 for his research on the neural control of salivary, gastric, and pancreatic secretion. A major reason for the success and novelty of his research was the use of unanesthetized dogs surgically prepared with chronic fistulas or gastric pouches that permitted repeated experiments in the same animal for months. Pavlov invented this chronic method because of the limitations he perceived in the use of acute anesthetized animals for investigating physiological systems. By introducing the chronic method and by showing its experimental advantages, Pavlov founded modern integrative physiology. This paper reviews Pavlov's journey from his birthplace in a provincial village in Russia to Stockholm to receive the Prize. It begins with childhood influences, describes his training and mentors, summarizes the major points of his research by reviewing his book Lectures on the Work of the Digestive Glands, and discusses his views on the relationship between physiology and medicine. PMID:10956230

  9. The Role of TCA Cycle Anaplerosis in Ketosis and Fatty Liver in Periparturient Dairy Cows

    PubMed Central

    White, Heather M.

    2015-01-01

    The transition to lactation period in dairy cattle is characterized by metabolic challenges, negative energy balance, and adipose tissue mobilization. Metabolism of mobilized adipose tissue is part of the adaptive response to negative energy balance in dairy cattle; however, the capacity of the liver to completely oxidize nonesterified fatty acids may be limited and is reflective of oxaloacetate pool, the carbon carrier of the tricarboxylic acid cycle. Alternative metabolic fates of acetyl-CoA from nonesterified fatty acids include esterification to triacylglycerides and ketogenesis, and when excessive, these pathways lead to fatty liver and ketosis. Examination of the anaplerotic and cataplerotic pull of oxaloacetate by the tricarboxylic acid cycle and gluconeogenesis may provide insight into the balance of oxidation and esterification of acetyl-CoA within the liver of periparturient dairy cows. PMID:26479386

  10. Position document: IgE-mediated cow's milk allergy.

    PubMed

    Martorell-Aragonés, A; Echeverría-Zudaire, L; Alonso-Lebrero, E; Boné-Calvo, J; Martín-Muñoz, M F; Nevot-Falcó, S; Piquer-Gibert, M; Valdesoiro-Navarrete, L

    2015-01-01

    The present document offers an update on the recommendations for managing patients with cow's milk allergy - a disorder that manifests in the first year of life, with an estimated prevalence of 1.6-3% in this paediatric age group. The main causal allergens are the caseins and proteins in lactoserum (beta-lactoglobulin, alpha-lactoalbumin), and the clinical manifestations are highly variable in terms of their presentation and severity. Most allergic reactions affect the skin, followed by the gastrointestinal and respiratory systems, and severe anaphylaxis may occur. The diagnosis of cow's milk allergy is based on the existence of a suggestive clinical history, a positive allergy study and the subsequent application of controlled exposure testing, which constitutes the gold standard for confirming the diagnosis. The most efficient treatment for cow's milk allergy is an elimination diet and the use of adequate substitution formulas. The elimination diet must include milk from other mammals (e.g., sheep, goat, etc.) due to the risk of cross-reactivity with the proteins of cow's milk. Most infants with IgE-mediated cow's milk allergy become tolerant in the first few years of life. In those cases where cow's milk allergy persists, novel treatment options may include oral immunotherapy, although most authors do not currently recommend this technique in routine clinical practice. Enough evidence is not there to confirm the efficacy of elimination diets in the mother and infant for preventing the appearance of cow's milk allergy. Likewise, no benefits have been observed with prebiotic and probiotic dietetic supplements in infants for preventing food allergy. PMID:25800671

  11. Effects of Dietary Energy Density and Intake on Maintenance Energy Requirements in Beef Cows 

    E-print Network

    Trubenbach, Levi Anthony

    2014-12-11

    nutritional manipulation strategies to optimize cow efficiency. An experiment was conducted to analyze the effects of dietary energy density and intake on maintenance energy requirements in beef cows. In a 2 x 2 factorial treatment arrangement, thirty...

  12. Adaptive Management

    EPA Science Inventory

    Adaptive management is an approach to natural resource management that emphasizes learning through management where knowledge is incomplete, and when, despite inherent uncertainty, managers and policymakers must act. Unlike a traditional trial and error approach, adaptive managem...

  13. Feed efficiency of tropically adapted breed and breed cross steers when fed in the southern plains.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Beef cows in the subtropical USA require that they be adapted to the stressors of the environment. However, calves produced in the region are usually grown and finished in more temperate regions. The objective of this paper is to determine the feed efficiency of steers from a 3-breed diallel mating ...

  14. Renal adaptation during hibernation

    PubMed Central

    Martin, Sandra L.; Jain, Swati; Keys, Daniel; Edelstein, Charles L.

    2013-01-01

    Hibernators periodically undergo profound physiological changes including dramatic reductions in metabolic, heart, and respiratory rates and core body temperature. This review discusses the effect of hypoperfusion and hypothermia observed during hibernation on glomerular filtration and renal plasma flow, as well as specific adaptations in renal architecture, vasculature, the renin-angiotensin system, and upregulation of possible protective mechanisms during the extreme conditions endured by hibernating mammals. Understanding the mechanisms of protection against organ injury during hibernation may provide insights into potential therapies for organ injury during cold storage and reimplantation during transplantation. PMID:24049148

  15. Endogenous and exogenous progesterone influence body temperature in dairy cows.

    PubMed

    Suthar, V S; Burfeind, O; Bonk, S; Dhami, A J; Heuwieser, W

    2012-05-01

    Three experiments were conducted to determine the effect of endogenous progesterone (P4) on body temperature comparing lactating, pregnant with lactating, nonpregnant cows, and to study the effect of exogenous P4 administered via a controlled internal drug release (CIDR) insert on body temperature in lactating dairy cows. Body temperature was measured vaginally and rectally using temperature loggers and a digital thermometer, respectively. In experiment 1, 10 cyclic lactating cows (3 primiparous, 7 multiparous) and 10 lactating, pregnant cows (3 primiparous, 7 multiparous) were included. Vaginal temperatures and serum P4 concentrations were greater in pregnant cows (vaginal: 0.3±0.01°C; P4: 5.5±0.4 ng/mL) compared with nonpregnant cows. In experiment 2, estrous cycles of 14 postpartum healthy, cyclic, lactating cows (10 primiparous, 4 multiparous) were synchronized, and cows were assigned randomly to 1 of 2 treatments (CIDR-P4 or CIDR-blank). A temperature logger was inserted 1 d after ovulation using a P4-free CIDR (CIDR-blank) and a CIDR containing 1.38g of P4 (CIDR-P4) in the control (n=7) and the P4-treated group (n=7), respectively. On d 3 after P4 treatment, vaginal temperature was 0.3±0.03°C greater compared with that on d 1 and d 5. In experiment 3, 9 cyclic multiparous lactating cows were enrolled 1±1 d after confirmed ovulation and a temperature logger inserted. Two days later, a CIDR-P4 was inserted on top of the CIDR-blank. On d 5±1 and d 7±1, respectively, the CIDR-P4 and CIDR-blank with the temperature logger were removed. During the CIDR-P4 treatment (48h), vaginal temperature was 0.2±0.05°C and 0.1±0.05°C greater than during the pre- and post-treatment periods (48h), respectively. Serum P4 concentration peaked during CIDR-P4 treatment (2.2±0.8 ng/mL) and was greater than during the pre-treatment period (0.2±0.2 ng/mL) for 48h. An increase in vaginal temperature could be due to endogenous and exogenous P4. However, a correlation between serum P4 concentrations and body temperature did not exist. Further investigations are warranted to better understand the pathways of the thermogenic effect of P4 on body temperature. PMID:22541466

  16. The effect of metritis on luteal function in dairy cows

    PubMed Central

    2013-01-01

    Background Disturbed uterine involution impairs ovarian function in the first weeks after calving. This study analyzed the long-term effect of metritis on luteal function of 47 lactating Holstein-Friesian cows during the first four postpartum estrous cycles. Cows with abnormal uterine enlargement and malodorous lochia were classified as having metritis (group M, n?=?18), and all others were considered healthy (group H, n?=?29). Luteal size was measured once between days 9 and 13 of the first (group H, n?=?11; group M, n?=?12), second (group H, n?=?23; group M, n?=?18) and fourth (group H, n?=?11; group M, n?=?7) postpartum luteal phases. Serum progesterone concentration was measured at the same time. Sixteen cows (group H, n?=?9; group M, n?=?7) underwent transvaginal luteal biopsy for gene expression analysis of steroidogenic regulatory proteins during the second and fourth cycles. Cows with persistence of the corpus luteum (CL) underwent determination of luteal size, luteal biopsy and serum progesterone measurement once between days 29 and 33, followed by prostaglandin treatment to induce luteolysis. The same procedures were repeated once between days 9 and 13 of the induced cycle. Results The cows in group M had smaller first-cycle CLs than the cows in group H (p?=?0.04), but progesterone concentrations did not differ between groups. Luteal size, progesterone concentration and gene expression did not differ between the two groups during the second and fourth cycles. Compared with healthy cows (10%), there was a trend (p?=?0.07) toward a higher prevalence of persistent CLs in cows with metritis (33%). Persistent CLs were limited to the first cycle. Persistent CLs and the induced cyclic CLs did not differ with regard to the variables investigated. Conclusions An effect of metritis on luteal activity was apparent in the first postpartum estrous cycle. However, after the first postpartum cycle, no differences occurred in analyzed parameters between metritis and control cows. Therefore, a metritis is able to impair luteal activity transiently, but does not seem to have a long-term effect on luteal function. PMID:24304943

  17. Simulation of MAD Cow Disease Propagation

    NASA Astrophysics Data System (ADS)

    Magdo?-Maksymowicz, M. S.; Maksymowicz, A. Z.; Go?dasz, J.

    Computer simulation of dynamic of BSE disease is presented. Both vertical (to baby) and horizontal (to neighbor) mechanisms of the disease spread are considered. The game takes place on a two-dimensional square lattice Nx×Ny = 1000×1000 with initial population randomly distributed on the net. The disease may be introduced either with the initial population or by a spontaneous development of BSE in an item, at a small frequency. Main results show a critical probability of the BSE transmission above which the disease is present in the population. This value is vulnerable to possible spatial clustering of the population and it also depends on the mechanism responsible for the disease onset, evolution and propagation. A threshold birth rate below which the population is extinct is seen. Above this threshold the population is disease free at equilibrium until another birth rate value is reached when the disease is present in population. For typical model parameters used for the simulation, which may correspond to the mad cow disease, we are close to the BSE-free case.

  18. Detection of tallow adulteration in cow ghee by derivative spectrophotometry

    PubMed Central

    Jirankalgikar, Nikhil M.; De, Subrata

    2014-01-01

    Context: Ghee is a widely consumed dairy product in India and that prepared from cow milk is mentioned in ayurvedic texts as an ingredient of many formulations/additive as well. Detection of cow ghee adulteration with vegetable oils/fats and animal body fats is a key concern. Indicated values for commonly used parameters to differentiate pure and adulterated ghee materials are many a times overlapping. Among reported techniques, ultraviolet fluorescence and paper chromatography technique are not that much sensitive while other methods require sophisticated instrumental facilities (such as gas chromatography, mass spectrometry) and costly analytical processes. Aims: The present paper deals with a promising spectroscopic method to determine the tallow adulteration in cow ghee. Materials and Methods: Ghee and tallow (taken in chloroform) as such and mixed in different proportions were scanned by spectrophotometer and their second order spectra were analyzed. Results: The value of the ratio of the absorbance of peaks at about 238 nm and 297 nm steadily decreases with the increasing proportion of tallow. This decrease shows consistent linearity suggesting its applicability for quantitative estimation of tallow in cow ghee. Conclusion: The developed derivative spectroscopic method is a rapid, sensitive, cost-effective method for detection of tallow adulteration in cow ghee. PMID:25097406

  19. BEEF SPECIES SYMPOSIUM: Beef production without mature cows.

    PubMed

    Seidel, G E; Whittier, J C

    2015-09-01

    Nutrients in animal feed get partitioned to growth, lactation, pregnancy, fat accretion, and/or maintenance. For mature beef cows, >80% of nutrients consumed annually go to unproductive maintenance. Integrated over the entire U.S. beef cattle production system, nearly one-half of the nutrients consumed go to maintenance of cow herds. This accounts for much of the inefficiency of beef production and can be minimized by the single-calf heifer system, in which heifers are fattened and slaughtered after having their first calf. We propose a modification, use of sexed semen, so that most heifers replace themselves with a heifer calf. This greatly decreases the size of the inherently inefficient cow herd required for beef production and greatly increases efficiency of beef production in terms of nutrients consumed and waste produced, such as methane, by increasing the ratio of nutrients used for growth to those used for maintenance. Additional management is required including AI, early weaning, and the attention required when calving 2-yr-old heifers. Low conception rates with sexed semen and less efficient growth of females than males also must be considered. However, these issues seem greatly outweighed by the benefits of increased efficiency from decreasing cow herd size while eliminating the need for breeding back lactating first-calf heifers, the need for castration, and health problems inherent in older cows such as mastitis and lameness. Moreover, the decreased generation interval can greatly accelerate genetic progress. PMID:26440323

  20. Milk Yield and Quality in Cows Sired by Different Beef Breeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maternal ability of beef cows, as indicated by milk yield and quality, influences both calf weaning weight and cow maintenance requirements. Three years of milk yield and quality data from 143 cows from Brangus dams and sired by 83 Bonsmara, Brangus, Charolais, Gelbvieh, Hereford, and Romosinuano b...

  1. Feed efficiency - how should it be used for the cow herd?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In cows, the most critical factor influencing the output component of efficiency is reproductive rate, and not necessarily weight gain. Thus benefits of selecting animals with desirable measures of feed efficiency on cow efficiency remain to be determined. The feed input component of cow efficiency...

  2. IMMUNE RESPONSES IN DAM AND FETUS AFTER EXPERIMENTAL INFECTION OF PREGNANT COWS WITH NEOSPORA CANINUM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The present study was performed to define the immune responses in the dam and fetus after infection of pregnant cows with N. caninum. Four cows were infected early in the second trimester of pregnancy (110 days of gestation) intravenously with 107 culture derived tachyzoites and three pregnant cows ...

  3. IMMUNE RESPONSES IN DAM AND FETUS AFTER EXPERIMENTAL INFECTION OF PREGNANT COWS WITH NEOSPOTA CANINUM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The present study was performed to define the immune responses in the dam and fetus after infection of pregnant cows with N. caninum. Four cows were infected early in the second trimester of pregnancy (110 days of gestation) intravenously with 107 culture derived tachyzoites and three pregnant cows ...

  4. STATE AND NATIONAL STANDARDIZED LACTATION AVERAGES BY BREED FOR COWS CALVING IN 2004

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Means for dairy cow lactation data used in national genetic evaluations and other USDA research are useful for indicating trends and describing cow populations. Breed lactation means are on a 305-day, twice daily milking, mature-equivalent basis from cows contributing to genetic evaluations. Data fo...

  5. SUPPLEMENTAL METHIONINE AND UREA FOR GESTATING BEEF COWS CONSUMING LOW QUALITY FORAGE DIETS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Studies conducted to evaluate Met requirements for late gestating beef cows consuming low quality forages. Inadequate supply of metabolizable AA may limit protein accretion during pregnancy in beef cows. In Exp. 1, two ruminally cannulated non-gestating non- lactating cows were utilized in a flow s...

  6. EFFECTS OF STALL SURFACE ON OCCUPACY AND POSTURAL CHANGES IN DAIRY COWS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A great deal of concern is allotted toward dairy cow comfort in order to optimize both cow welfare and milk production. Toward this end, producers are utilizing various stall surfaces in order to optimize cow comfort, while at the same time decreasing health concerns. Experiment 1 was designed to ...

  7. State and National Standardized Lactation Averages by Breed for Cows Calving in 2005

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Means for dairy cow lactation data used in national genetic evaluations and other USDA research are useful for indicating trends and describing cow populations. Breed lactation means are on a 305-day, twice daily milking, mature-equivalent basis from cows contributing to genetic evaluations. Data fo...

  8. RESUMPTION OF POSTPARTUM LUTEAL FUNCTION OF PRIMIPAROUS, SUCKLED BEEF COWS EXPOSED CONTINUOUSLY TO BULL URINE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We tested the hypotheses that interval from urine exposure to resumption of luteal activity and proportions of cows that resume luteal activity by the end of the urine-exposure period do not differ between cows exposed to mature bull urine or steer urine. Thirty-eight Angus x Hereford cows, four mat...

  9. Variation in enteric methane emissions among cows on commercial dairy farms.

    PubMed

    Bell, M J; Potterton, S L; Craigon, J; Saunders, N; Wilcox, R H; Hunter, M; Goodman, J R; Garnsworthy, P C

    2014-09-01

    Methane (CH4) emissions by dairy cows vary with feed intake and diet composition. Even when fed on the same diet at the same intake, however, variation between cows in CH4 emissions can be substantial. The extent of variation in CH4 emissions among dairy cows on commercial farms is unknown, but developments in methodology now permit quantification of CH4 emissions by individual cows under commercial conditions. The aim of this research was to assess variation among cows in emissions of eructed CH4 during milking on commercial dairy farms. Enteric CH4 emissions from 1964 individual cows across 21 farms were measured for at least 7 days/cow using CH4 analysers at robotic milking stations. Cows were predominantly of Holstein Friesian breed and remained on the same feeding systems during sampling. Effects of explanatory variables on average CH4 emissions per individual cow were assessed by fitting a linear mixed model. Significant effects were found for week of lactation, daily milk yield and farm. The effect of milk yield on CH4 emissions varied among farms. Considerable variation in CH4 emissions was observed among cows after adjusting for fixed and random effects, with the CV ranging from 22% to 67% within farms. This study confirms that enteric CH4 emissions vary among cows on commercial farms, suggesting that there is considerable scope for selecting individual cows and management systems with reduced emissions. PMID:24946166

  10. [The effectiveness of clanobutin for the prevention of postpartum primary ketosis in dairy cows].

    PubMed

    Karatzias, H; Roubies, N; Papasteriadis, A; Papadopoulos, N

    1993-10-01

    Investigations on the efficacy of Clanobutin for prophylaxis of postpartum primary ketosis were performed in dairy cows. No one cow in the group of 15 treated animals diseased by ketosis, but 2 of 15 control animals showed signs of primary ketosis. The results show the good efficacy of Clanobutin for prophylaxis of postpartum primary ketosis in dairy cows. PMID:8261909

  11. Genetic Evaluations Using Combined Data from All Breeds and Crossbred Cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An all-breed animal model was developed for routine genetic evaluations of US dairy cattle. Data sets from individual breeds were combined, and records from crossbred cows were included. About 1% of recent cows were first generation crossbreds. Numbers of cows with records since 1960 ranged from 10 ...

  12. The effect of floor surface on dairy cow immune function and locomotion score

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The study evaluated the effect of 2 dairy cow housing systems on cow locomotion, leukocyte activity and expression of genes associated with lameness, during the dry and peri-parturient period. Cows were assigned to free-stall housing with either rubber (RUB; n=13) or concrete (CON; n=14) at the feed...

  13. STATE AND NATIONAL STANDARDIZED LACTATION AVERAGES BY BREED FOR COWS CALVING IN 2000

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Means for dairy cow lactation data used in national genetic evaluations and other USDA research are useful for indicating trends and describing cow populations. Breed lactation means are on a 305-day, twice daily milking, mature-equivalent basis from cows contributing to genetic evaluations. Data fo...

  14. THE EFFECT OF SOLANUM GLAUCOPHYLLUM ON CALCIUM AND PHOSPHORUS UTILIZATION IN LACTATING COWS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of the study was to determine if Solanum glaucophyllum (Sg) could serve as a source of 1,25(OH)2D3 to increase calcium (Ca) and phosphorus (P) utilization and, therefore, decrease fecal Ca and P excretion in lactating cows. Ten primiparous, lactating Holstein cows were used. Four cows ...

  15. Heterosis for reproductive traits in young F1, Romosinuano, Brahman, and Angus cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this research was to estimate heterosis for reproductive performance of young cows that were produced by matings of Romosinuano (R), Brahman (B), and Angus (A) bulls and cows. Cows (n = 659) were spring-born in 2002 to 2005. After weaning, they were placed with bulls until confirm...

  16. Physiology of iron metabolism.

    PubMed

    Waldvogel-Abramowski, Sophie; Waeber, Gérard; Gassner, Christoph; Buser, Andreas; Frey, Beat M; Favrat, Bernard; Tissot, Jean-Daniel

    2014-06-01

    A revolution occurred during the last decade in the comprehension of the physiology as well as in the physiopathology of iron metabolism. The purpose of this review is to summarize the recent knowledge that has accumulated, allowing a better comprehension of the mechanisms implicated in iron homeostasis. Iron metabolism is very fine tuned. The free molecule is very toxic; therefore, complex regulatory mechanisms have been developed in mammalian to insure adequate intestinal absorption, transportation, utilization, and elimination. 'Ironomics' certainly will be the future of the understanding of genes as well as of the protein-protein interactions involved in iron metabolism. PMID:25053935

  17. Physiology of Iron Metabolism

    PubMed Central

    Waldvogel-Abramowski, Sophie; Waeber, Gérard; Gassner, Christoph; Buser, Andreas; Frey, Beat M.; Favrat, Bernard; Tissot, Jean-Daniel

    2014-01-01

    Summary A revolution occurred during the last decade in the comprehension of the physiology as well as in the physiopathology of iron metabolism. The purpose of this review is to summarize the recent knowledge that has accumulated, allowing a better comprehension of the mechanisms implicated in iron homeostasis. Iron metabolism is very fine tuned. The free molecule is very toxic; therefore, complex regulatory mechanisms have been developed in mammalian to insure adequate intestinal absorption, transportation, utilization, and elimination. ‘Ironomics’ certainly will be the future of the understanding of genes as well as of the protein-protein interactions involved in iron metabolism. PMID:25053935

  18. Pioneering in gravitational physiology

    NASA Technical Reports Server (NTRS)

    Soffen, G. A.

    1983-01-01

    Gravity affects biology at almost all levels above that of the cell organelle. Attention is presently given to progress made in the understanding of gravitational effects through studies employing centrifuges, clinostats, inverted preparations, linear devices, water immersion, free fall, and short- and long-term spaceflight. The cardiovascular changes which cause malaise and illness during the first few days of extended space missions are the direct result of fluid translocation from the lower extremities. Upon reentry, there is hypovolumnia and a cardiovascular deconditioning that can include tachycardia, changes in arterial blood pressure, narrow pulse pressure, and syncope. Attention is also given to NASA's gravitational physiology reseach program.

  19. Peptidomic profile of milk of Holstein cows at peak lactation

    PubMed Central

    Dallas, David C.; Guerrero, Andres; Parker, Evan A.; Garay, Luis A.; Bhandari, Aashish; Lebrilla, Carlito B.; Barile, Daniela; German, J. Bruce

    2014-01-01

    Bovine milk is known to contain naturally occurring peptides, but relatively few of their sequences have been determined. Human milk contains hundreds of endogenous peptides and the ensemble has been documented for antimicrobial actions. Naturally occurring peptides from bovine milk were sequenced and compared with human milk peptides. Bovine milk samples from six cows in second stage peak lactation at 78–121 days post- partum revealed 159 peptides. Most peptides (73%) were found in all six cows sampled, demonstrating the similarity of the intra-mammary peptide degradation across these cows. One peptide sequence, ALPIIQKLEPQIA from bovine perilipin 2 was identical to another found in human milk. Most peptides derived from ?-casein, ?s1-casein and ?s2- casein. No peptides derived from abundant bovine milk proteins like lactoferrin, ?- lactoglobulin and secretory immunoglobulin A. The enzymatic cleavage analysis revealed that milk proteins were degraded by plasmin, cathepsins B and D and elastase in all samples. PMID:24344900

  20. Physiology of bile secretion

    PubMed Central

    Esteller, Alejandro

    2008-01-01

    The formation of bile depends on the structural and functional integrity of the bile-secretory apparatus and its impairment, in different situations, results in the syndrome of cholestasis. The structural bases that permit bile secretion as well as various aspects related with its composition and flow rate in physiological conditions will first be reviewed. Canalicular bile is produced by polarized hepatocytes that hold transporters in their basolateral (sinusoidal) and apical (canalicular) plasma membrane. This review summarizes recent data on the molecular determinants of this primary bile formation. The major function of the biliary tree is modification of canalicular bile by secretory and reabsorptive processes in bile-duct epithelial cells (cholangiocytes) as bile passes through bile ducts. The mechanisms of fluid and solute transport in cholangiocytes will also be discussed. In contrast to hepatocytes where secretion is constant and poorly controlled, cholangiocyte secretion is regulated by hormones and nerves. A short section dedicated to these regulatory mechanisms of bile secretion has been included. The aim of this revision was to set the bases for other reviews in this series that will be devoted to specific issues related with biliary physiology and pathology. PMID:18837079

  1. The Physiology of Glucagon

    PubMed Central

    Taborsky, Gerald J

    2010-01-01

    This short review outlines the physiology of glucagon in vivo, with an emphasis on its neural control, the author’s area of interest. Glucagon is secreted from alpha cells, which are a minority of the pancreatic islet. Anatomically, they are down stream from the majority islet beta cells. Beta-cell secretory products restrain glucagon secretion. Activation of the autonomic nerves, which innervate the islet, increases glucagon secretion. Glucagon is secreted into the portal vein and thus has its major physiologic action at the liver to break down glycogen. Glucagon thereby maintains hepatic glucose production during fasting and increases hepatic glucose production during stress, including the clinically important stress of hypoglycemia. Three different mechanisms proposed to stimulate glucagon secreted during hypoglycemia are discussed: (1) a stimulatory effect of low glucose directly on the alpha cell, (2) withdrawal of an inhibitory effect of adjacent beta cells, and (3) a stimulatory effect of autonomic activation. In type 1 diabetes (T1DM), increased glucagon secretion contributes to the elevated ketones and acidosis present in diabetic ketoacidosis (DKA). It also contributes to the hyperglycemia seen with or without DKA. The glucagon response to insulin-induced hypoglycemia is impaired soon after the development of T1DM. The mediators of this impairment include loss of beta cells and loss of sympathetic nerves from the autoimmune diabetic islet. PMID:21129328

  2. Predator exposure alters stress physiology in guppies across timescales Eva K. Fischer a,

    E-print Network

    Hofmann, Hans A.

    Predator exposure alters stress physiology in guppies across timescales Eva K. Fischer a, , Rayna M Cortisol Glucocorticoids Adaptive evolution Predation Stress In vertebrates, glucocorticoids mediate a wide-range of responses to stressors. For this reason, they are implicat- ed in adaptation to changes in predation

  3. Health and productivity of dairy cows fed polychlorinated biphenyls

    SciTech Connect

    Willett, L.B.; Liu, T.T.; Durst, H.I.; Smith, K.L.; Redman, D.R.

    1987-07-01

    Holstein cows were studied through a complete lactation, a nonlactating period, and 42 days of a subsequent lactation for overt and subtle responses to a commercial mixture of polychlorinated biphenyls. Dosed cows (n = 4) received consecutive 60-day periods of daily dosing with 10, 100, and 1000 mg of Aroclor 1254. Control cows (n = 6) received daily sham doses. The following were recorded: daily milk production, feed intake, and health observations; weekly body weight, temperature, heart and respiratory rates and rectal palpation; semi-monthly clinical chemistry determinations; and monthly milk fat, microbiological culture of quarter foremilk samples, and composite milk somatic cell counts. Mean daily milk production (22.4 +/- 1.1 vs 24.8 +/- 1.0 kg) and net energy of a complete lactation (1.46 +/- 0.05 vs 1.45 +/- 0.03 Mcal/kg dry matter intake) were not different (p = 0.85) for control and PCB-dosed cows. Milk production during the first 42 days of the subsequent lactation was also similar for control and dosed cows. Occurrences of injuries, dysfunctions, and general infections were not related to polychlorinated biphenyl exposure. Intramammary infections were detected for both lactations with 51 and 32 infections detected in microbiological cultures, respectively, for the control and dosed groups. Environmental pathogens were most frequently isolated from cases of clinically apparent mastitis. The majority of quarter infections detected were due to Corynebacterium bovis. Only one animal (dosed, necropsy revealed left oviduct obstructed) failed to conceive with three to six services required before conception for the other control and dosed cows. Exposure to polychlorinated biphenyls resulting in maximal residues in milk fat, near 100 micrograms/g, had no apparent effect on health and productivity.

  4. The effect of housing on calving behavior and calf vitality in Holstein and Jersey dairy cows.

    PubMed

    Campler, M; Munksgaard, L; Jensen, M B

    2015-03-01

    The present study investigated how calving behavior and calf vitality in Holstein and Jersey dairy cows were affected by housing during the final 4 wk precalving. One hundred twenty-one cows (36 primiparous and 85 multiparous) were moved either to a group pen with deep straw bedding or into freestall housing 4 wk before the expected calving date. Individual straw-bedded maternity pens were placed adjacent to the straw-bedded group pens, and cows were moved to the maternity pens before calving. Cows that spent more than 12 h in the maternity pen before calving and calved unassisted were included in this study (39 multiparous cows and 15 primiparous cows). Dams were observed from 6 h before calving until 6 h after calving. The time from the onset of rhythmical abdominal contractions (defined as the onset of stage II labor), the time from a visible amniotic sac, and the time from visible calf feet until the birth of the calf were recorded. Furthermore, the cows' latency to stand up after birth was recorded. Calves were observed during the first 6 h after birth and the latency to first standing attempt, to first successful standing, to first suckle attempt, and to first successful suckling were recorded. Cows previously housed in straw pens expelled the calf faster once the calves' feet were visible compared with cows previously housed in freestalls. Multiparous cows stood sooner and licked their calf sooner after birth compared with primiparous cows. Jersey calves of cows previously housed in straw pens also stood up and suckled their dams sooner compared with Jersey calves of cows previously housed in freestalls. Holstein cows previously housed in straw pens tended to stand up sooner compared with Holstein cows previously housed in freestalls. These results suggest that a longer period of housing on deep-bedded straw compared with freestalls with mattresses before calving may facilitate the calving process, whereas the effect on calf vitality needs further investigation. PMID:25597972

  5. Host specificity of the ruminal bacterial community in the dairy cow followng near-total exchange of ruminal contents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this study was to examine the stability and host specificity of a cow’s ruminal bacterial community following massive challenge with the ruminal microflora from another cow. In each of two experiments, one pair of cows was selected on the basis of differences in ruminal bacterial comm...

  6. Evaluation of heterosis and heterosis retention in Bos taurus-Bos indicus crossbred cattle for productivity traits in cows 

    E-print Network

    Meuchel, Meredith Christine

    2005-11-01

    Reproductive and weight traits were analyzed for Angus (A), Brahman (B), Hereford (H), and Nellore (N) straightbred cows; F1 NA cows; 3/8N 5/8A cows and quarter blood composite cows (BANH) of the four straightbreds in ...

  7. Short communication: Feeding red clover cut in the afternoon or morning to late-lactation dairy cows.

    PubMed

    Antaya, N T; Berthiaume, R; Tremblay, G F; Brito, A F

    2015-10-01

    Forages cut in the afternoon (p.m.) generally yield a higher concentration of nonstructural carbohydrates (NSC) than those cut in the morning (a.m.). We aimed to compare the effects of p.m.-cut red clover baleage (p.m.-RC) versus a.m.-cut RC baleage (a.m.-RC) on milk yield, concentrations and yields of milk components, and apparent total-tract digestibility of nutrients in late-lactation Holstein cows. Twelve multiparous and 2 primiparous Holstein cows received a total mixed ration containing, on a dry matter (DM) basis, 65% p.m.-RC or a.m.-RC plus 35% concentrate in a crossover design with 14 d for diet adaptation and 7 d for data and sample collection. One RC field was split in 2 with the first half cut in the afternoon (1600 h) and the second half in the following morning (0600 h). The p.m.-RC and a.m.-RC contained (% of DM): 12.6 versus 9.43% NSC in samples collected before the beginning of the experiment and 7.49 versus 7.79% NSC in samples collected during the sampling periods (i.e., d 14 to 21). The total mixed rations averaged 18.2 and 17.5% NSC for the p.m.-RC and a.m.-RC, respectively. Feeding p.m.-RC or a.m.-RC did not improve feed intake or milk yield and composition in late-lactation dairy cows. However, milk urea N and plasma urea N were both lowest in cows offered p.m.-RC. With the exception of the apparent total-tract digestibility of DM, which was highest in cows fed p.m.-RC, no other changes in nutrient digestibility were observed. Similarly, no treatment effect was observed for the urinary excretion of N and purine derivatives. Further research is needed to better understand NSC losses during storage and the associated effects on baleage quality and animal performance. PMID:26254532

  8. Ultrasonographic Examination of the Rumen in Healthy Cows

    PubMed Central

    Imran, Sheikh; Kumar, Adarsh; Tyagi, S. P.; Kumar, Amit; Sharma, Shivali

    2011-01-01

    10 healthy Indian Jersey/Red Sindhi crossbred nonpregnant cows were subjected to transabdominal ultrasonography to develop baseline topographical data of the rumen. The wall of the rumen could be identified as a thick echogenic line adjacent to the left abdominal wall from left flank to 8th intercostal space. The motility pattern of rumen was characterized by approximately 1 contraction every minute. The mean amplitude of the ruminal contraction was 3.2?cm. Ultrasonography of the rumen in healthy cows is a useful adjunct to the noninvasive diagnostic investigation of the rumen. PMID:21547228

  9. Estrus-related odors in cows: time of occurrence.

    PubMed

    Kiddy, C A; Mitchell, D S

    1981-02-01

    One Catahoula Leopard Cowdog and three German Shepherd dogs, previously trained to detect odors characteristic of estrus in cows, were used in three experiments to determine when estrus-related odor first appears, how long it persists, and when it disappears in relation to time of estrus. Samples were swabs of reproductive tract fluids taken from vaginas of cycling cows on the day of estrus, at diestrus (8 to 10 days after estrus), and at daily intervals before and after estrus. Estrous odor emerges slowly during the 3 days before estrus, reaches a definite peak in intensity on the day of estrus, and disappears within 1 day thereafter. PMID:7276312

  10. Mechanism of Salinity Tolerance in Plants: Physiological, Biochemical, and Molecular Characterization

    PubMed Central

    Huang, Bingru

    2014-01-01

    Salinity is a major abiotic stress limiting growth and productivity of plants in many areas of the world due to increasing use of poor quality of water for irrigation and soil salinization. Plant adaptation or tolerance to salinity stress involves complex physiological traits, metabolic pathways, and molecular or gene networks. A comprehensive understanding on how plants respond to salinity stress at different levels and an integrated approach of combining molecular tools with physiological and biochemical techniques are imperative for the development of salt-tolerant varieties of plants in salt-affected areas. Recent research has identified various adaptive responses to salinity stress at molecular, cellular, metabolic, and physiological levels, although mechanisms underlying salinity tolerance are far from being completely understood. This paper provides a comprehensive review of major research advances on biochemical, physiological, and molecular mechanisms regulating plant adaptation and tolerance to salinity stress. PMID:24804192

  11. Human Physiological Responses to Acute and Chronic Cold Exposure

    NASA Technical Reports Server (NTRS)

    Stocks, Jodie M.; Taylor, Nigel A. S.; Tipton, Michael J.; Greenleaf, John E.

    2001-01-01

    When inadequately protected humans are exposed to acute cold, excessive body heat is lost to the environment and unless heat production is increased and heat loss attenuated, body temperature will decrease. The primary physiological responses to counter the reduction in body temperature include marked cutaneous vasoconstriction and increased metabolism. These responses, and the hazards associated with such exposure, are mediated by a number of factors which contribute to heat production and loss. These include the severity and duration of the cold stimulus; exercise intensity; the magnitude of the metabolic response; and individual characteristics such as body composition, age, and gender. Chronic exposure to a cold environment, both natural and artificial, results in physiological alterations leading to adaptation. Three quite different, but not necessarily exclusive, patterns of human cold adaptation have been reported: metabolic, hypothermic, and insulative. Cold adaptation has also been associated with an habituation response, in which there is a desensitization, or damping, of the normal response to a cold stress. This review provides a comprehensive analysis of the human physiological and pathological responses to cold exposure. Particular attention is directed to the factors contributing to heat production and heat loss during acute cold stress, and the ability of humans to adapt to cold environments.

  12. Choosing the Time of Year to Breed and Calve Beef Cows in Texas 

    E-print Network

    Sprott, L. R.

    2001-01-04

    cows so that they can show estrus early in the breeding period. Table 2 shows that cows that display estrus within the first 21 days of breeding have higher pregnancy rates compared to cows displaying estrus after the first 21 days of breeding.... Consequently, pregnancy rates are high in herds that have a high proportion of cows showing estrus early in the breeding period. Principle 3?Most of the pregnancies within a herd occur in the cows with highest fertility. Table 3 shows that 95 percent (Trial 1...

  13. "Their pineal glands aglow": Theosophical physiology in Ulysses.

    PubMed

    Morrisson, Mark S

    2008-01-01

    This article argues that Joyce's engagements with the Theosophy of the Dublin literary world amount to more than simple parody. In Ulysses, Joyce portrays Theosophy's efforts to offer an alternative understanding of physiology to that of the medical establishment as a form of boundary work, an adaptation of the discourse of modern medical research to fashion modern mysticism as a science. Ultimately, Joyce rejects Theosophical physiology and its evolutionary scientism because it provides an unsatisfactory rhetorical body, a failed attempt to renegotiate the boundaries between scientific materialism and spirituality in the awkward modernity of Dublin in 1904. PMID:20836274

  14. Relationship of psychological and physiological parameters during an arctic ski expedition

    NASA Astrophysics Data System (ADS)

    Bishop, Sheryl L.; Grobler, Lukas C.; SchjØll, Olaf

    2001-08-01

    Considerable data (primarily physiological) have been collected during expeditions in extreme environments over the last century. Physiological measurements have only recently been examined in association with the emotional or behavioral state of the subject. Establishing this psychophysiological relationship is essential to understanding fully the adaptation of humans to the stresses of extreme environments. This pilot study investigated the simultaneous collection of physiological, psychological and behavioral data from a two-man Greenland expedition in order to model how specific relationships between physiological and psychological adaptation to a polar environment may be identified. The data collected describes changes in adrenal and other hormonal activity and psychological functioning. Levels of cortisol and testosterone were calculated. Factors influencing the plasma profiles of the aforementioned included 24-hour sunlight, high calorific intake of more than 28 000 kJ/day and extreme physical exercise. There was a difference between individual psychological profiles as well as self-report stress and physiological stress.

  15. Tissue tracking in thermo-physiological imagery through spatio-temporal smoothing.

    PubMed

    Zhou, Yan; Tsiamyrtzis, Panagiotis; Pavlidis, Ioannis T

    2009-01-01

    Accurate tracking of facial tissue in thermal infrared imaging is challenging because it is affected not only by positional but also physiological (functional) changes. This article presents a particle filter tracker driven by a probabilistic template function with both spatial and temporal smoothing components, which is capable of adapting to abrupt positional and physiological changes. The method was tested on tracking facial regions of subjects under varying physiological and environmental conditions in 12 thermal clips. It demonstrated robustness and accuracy, outperforming other strategies. This new method promises improved performance in a host of biomedical applications that involve physiological measurements on the face, like unobtrusive sleep studies. PMID:20426220

  16. Trichinella spiralis: the evolution of adaptation and parasitism

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Parasitism among nematodes has occurred in multiple, independent events. Deciphering processes that drive species diversity and adaptation are keys to understanding parasitism and advancing control strategies. Studies have been put forth on morphological and physiological aspects of parasitism and a...

  17. Lameness Detection in Dairy Cows: Part 1. How to Distinguish between Non-Lame and Lame Cows Based on Differences in Locomotion or Behavior

    PubMed Central

    Van Nuffel, Annelies; Zwertvaegher, Ingrid; Pluym, Liesbet; Van Weyenberg, Stephanie; Thorup, Vivi M.; Pastell, Matti; Sonck, Bart; Saeys, Wouter

    2015-01-01

    Simple Summary Scoring cattle for lameness based on changes in locomotion or behavior is essential for farmers to find and treat their lame animals. This review discusses the normal locomotion of cows in order to define abnormal locomotion due to lameness. It furthermore provides an overview of various relevant visual locomotion scoring systems that are currently being used as well as practical considerations when assessing lameness on a commercial farm. Abstract Due to its detrimental effect on cow welfare, health and production, lameness in dairy cows has received quite a lot of attention in the last few decades—not only in terms of prevention and treatment of lameness but also in terms of detection, as early treatment might decrease the number of severely lame cows in the herds as well as decrease the direct and indirect costs associated with lameness cases. Generally, lame cows are detected by the herdsman, hoof trimmer or veterinarian based on abnormal locomotion, abnormal behavior or the presence of hoof lesions during routine trimming. In the scientific literature, several guidelines are proposed to detect lame cows based on visual interpretation of the locomotion of individual cows (i.e., locomotion scoring systems). Researchers and the industry have focused on automating such observations to support the farmer in finding the lame cows in their herds, but until now, such automated systems have rarely been used in commercial herds. This review starts with the description of normal locomotion of cows in order to define ‘abnormal’ locomotion caused by lameness. Cow locomotion (gait and posture) and behavioral features that change when a cow becomes lame are described and linked to the existing visual scoring systems. In addition, the lack of information of normal cow gait and a clear description of ‘abnormal’ gait are discussed. Finally, the different set-ups used during locomotion scoring and their influence on the resulting locomotion scores are evaluated. PMID:26479389

  18. Single Cell Physiology

    NASA Astrophysics Data System (ADS)

    Neveu, Pierre; Sinha, Deepak Kumar; Kettunen, Petronella; Vriz, Sophie; Jullien, Ludovic; Bensimon, David

    The possibility to control at specific times and specific places the activity of biomolecules (enzymes, transcription factors, RNA, hormones, etc.) is opening up new opportunities in the study of physiological processes at the single cell level in a live organism. Most existing gene expression systems allow for tissue specific induction upon feeding the organism with exogenous inducers (e.g., tetracycline). Local genetic control has earlier been achieved by micro-injection of the relevant inducer/repressor molecule, but this is an invasive and possibly traumatic technique. In this chapter, we present the requirements for a noninvasive optical control of the activity of biomolecules and review the recent advances in this new field of research.

  19. Adaptive SPECT

    PubMed Central

    Barrett, Harrison H.; Furenlid, Lars R.; Freed, Melanie; Hesterman, Jacob Y.; Kupinski, Matthew A.; Clarkson, Eric; Whitaker, Meredith K.

    2008-01-01

    Adaptive imaging systems alter their data-acquisition configuration or protocol in response to the image information received. An adaptive pinhole single-photon emission computed tomography (SPECT) system might acquire an initial scout image to obtain preliminary information about the radiotracer distribution and then adjust the configuration or sizes of the pinholes, the magnifications, or the projection angles in order to improve performance. This paper briefly describes two small-animal SPECT systems that allow this flexibility and then presents a framework for evaluating adaptive systems in general, and adaptive SPECT systems in particular. The evaluation is in terms of the performance of linear observers on detection or estimation tasks. Expressions are derived for the ideal linear (Hotelling) observer and the ideal linear (Wiener) estimator with adaptive imaging. Detailed expressions for the performance figures of merit are given, and possible adaptation rules are discussed. PMID:18541485

  20. Physiological Roles of Adipokines, Hepatokines, and Myokines in Ruminants.

    PubMed

    Roh, Sang-Gun; Suzuki, Yutaka; Gotoh, Takafumi; Tatsumi, Ryuichi; Katoh, Kazuo

    2016-01-01

    Since the discovery of leptin secreted from adipocytes, specialized tissues and cells have been found that secrete the several peptides (or cytokines) that are characterized to negatively and positively regulate the metabolic process. Different types of adipokines, hepatokines, and myokines, which act as cytokines, are secreted from adipose, liver, and muscle tissue, respectively, and have been identified and examined for their physiological roles in humans and disease in animal models. Recently, various studies of these cytokines have been conducted in ruminants, including dairy cattle, beef cattle, sheep, and goat. Interestingly, a few cytokines from these tissues in ruminants play an important role in the post-parturition, lactation, and fattening (marbling) periods. Thus, understanding these hormones is important for improving nutritional management in dairy cows and beef cattle. However, to our knowledge, there have been no reviews of the characteristics of these cytokines in beef and dairy products in ruminants. In particular, lipid and glucose metabolism in adipose tissue, liver tissue, and muscle tissue are very important for energy storage, production, and synthesis, which are regulated by these cytokines in ruminant production. In this review, we summarize the physiological roles of adipokines, hepatokines, and myokines in ruminants. This discussion provides a foundation for understanding the role of cytokines in animal production of ruminants. PMID:26732322

  1. The Physiology of Bed Rest. Chapter 39

    NASA Technical Reports Server (NTRS)

    Fortney, Suzanne M.; Schneider, Victor S.; Greenleaf, John E.

    1996-01-01

    Prolonged rest in bed has been utilized by physicians and other health-care workers to immobilize and confine patients for rehabilitation and restoration of health since time immemorial. The sitting or horizontal position is sought by the body to relieve the strain of the upright or vertical postures, for example during syncopal situations, bone fractures, muscle injuries, fatigue, and probably also to reduce energy expenditure. Most health-care personnel are aware that adaptive responses occurring during bed rest proceed concomitantly with the healing process; signs and symptoms associated with the former should be differentiated from those of the latter. Not all illnesses and infirmities benefit from prolonged bed rest. Considerations in prescribing bed rest for patients-including duration, body position, mode and duration of exercise, light-dark cycles, temperature, and humidity-have not been investigated adequately. More recently, adaptive physiological responses have been measured in normal, healthy subjects in the horizontal or slightly head-down postures during prolonged bed rest as analogs for the adaptive responses of astronauts exposed to the microgravity environment of outer and bed-rest research.

  2. Contour adaptation.

    PubMed

    Anstis, Stuart

    2013-01-01

    It is known that adaptation to a disk that flickers between black and white at 3-8 Hz on a gray surround renders invisible a congruent gray test disk viewed afterwards. This is contrast adaptation. We now report that adapting simply to the flickering circular outline of the disk can have the same effect. We call this "contour adaptation." This adaptation does not transfer interocularly, and apparently applies only to luminance, not color. One can adapt selectively to only some of the contours in a display, making only these contours temporarily invisible. For instance, a plaid comprises a vertical grating superimposed on a horizontal grating. If one first adapts to appropriate flickering vertical lines, the vertical components of the plaid disappears and it looks like a horizontal grating. Also, we simulated a Cornsweet (1970) edge, and we selectively adapted out the subjective and objective contours of a Kanisza (1976) subjective square. By temporarily removing edges, contour adaptation offers a new technique to study the role of visual edges, and it demonstrates how brightness information is concentrated in edges and propagates from them as it fills in surfaces. PMID:23447679

  3. [The physiological aspects of individual human eco-adaptation].

    PubMed

    Sidorov, Iu A

    1994-06-01

    These data obtained shows the typological pattern of the brain neurodynamics to be related to functional self-controlling mechanisms as reflected in probable structure of the interlinks among the EEG basic rhythms. Three types were singled out with respective dynamics of the functional state readjustment under a prolonged effect of ambient factors. PMID:7531068

  4. Obesity, a Disease of Adaptation to Environmental & Physiological Stressors

    ERIC Educational Resources Information Center

    Bijaoui, Nadia Judith

    2012-01-01

    Background: The educational intervention of this Applied Dissertation consisted of a presentation during which self-selected volunteers were introduced to relevant literature focusing on less known factors causing the disease of obesity and contrasting from behavior. Purpose: The workshop was structured to address the problem statement: "The…

  5. Evaluation of subclinical endometritis and consequences on fertility in piedmontese beef cows.

    PubMed

    Ricci, A; Gallo, S; Molinaro, F; Dondo, A; Zoppi, S; Vincenti, L

    2015-02-01

    Subclinical endometritis (SEM) is poorly investigated in beef cows, as stated in the literature. This project aims to evaluate the rate and the consequences of SEM in Piedmontese cows, with a focus on bacteriological findings and fertility parameters. Uterine cytology was performed for 97 subjects; a total of 31% of the cows were diagnosed as being positive for SEM and as having an 8% neutrophil (PMN) presence on the slide, which is considered as the best cut-off to diagnose the pathology. Only 13% of the cows positive for SEM were pregnant within 130 dpp and generally showed increases of 40 days in the partum to conception interval compared with the negative cows (142 vs 182, p = 0.01). Cows positive for both bacteriology and cytology showed a lower fertility than cows with only inflammation or only a bacterial presence (p = 0.0004). Bacterial isolation detected different species, but no difference in regard to the impact of these bacteria on SEM was shown. Parity, presence of calves, hygiene condition, age and number of service did not affect whether a cow was positive for subclinical endometritis (p < 0.05). The housing system (free stalls vs tie stalls) used seems to affect the SEM rate in Piedmontese cows; cows bred in tie stalls were more likely to be positive for SEM (OR = 2.2; p = 0.04). In conclusion, cytology seems to be a good technique for the diagnosis of subclinical endometritis in beef cows, and as in dairy cows, subclinical endometritis has a detrimental effect on fertility, causing an increase in partum to conception and a decrease in the rate of cows who become pregnant within 130 dpp, particularly for those cows housed in a tie stall. PMID:25598020

  6. A modified presynchronization protocol improves fertility to timed artificial insemination in lactating dairy cows.

    PubMed

    Navanukraw, C; Redmer, D A; Reynolds, L P; Kirsch, J D; Grazul-Bilska, A T; Fricke, P M

    2004-05-01

    To compare 2 hormonal protocols for submission of lactating dairy cows for timed artificial insemination (TAI), nonpregnant lactating Holstein cows (n = 269) >60 d in milk were randomly assigned to each of 2 treatments to receive TAI (TAI = d 0). Cows assigned to the first treatment (Ovsynch, n = 134) received 50 microg of GnRH (d -10), 25 mg of PGF2alpha (d -3), and 50 microg of GnRH (d -1) beginning at a random stage of the estrous cycle. Cows assigned to the second treatment (Presynch, n = 135) received Ovsynch but with the addition of 2 PGF2alpha (25 mg) injections administered 14 d apart beginning 28 d (d -38 and -24) before initiation of Ovsynch. All cows received TAI 16 to 18 h after the second GnRH injection. Ovulatory response after each GnRH injection for a subset of cows (n = 109) and pregnancy status 42 d after TAI for all cows were assessed using transrectal ultrasonography. Based on serum progesterone (P4) profiles determined for a subset of cows (n = 109), P4 concentrations decreased for Presynch cows after the first 2 PGF2alpha injections, and Presynch cows had greater P4 concentrations at the PGF2alpha injection on d -3 compared with Ovsynch cows. Although the proportion of cows ovulating after the first and second GnRH injections did not differ statistically between treatments (41.1 and 69.6% vs. 35.9 and 81.1% for Ovsynch vs. Presynch, respectively), pregnancy rate per artificial insemination (PR/AI) at 42 d post TAI was greater for Presynch than for Ovsynch cows (49.6 vs. 37.3%). Parity, DIM, and body condition score (BCS) at TAI did not affect PR/AI to TAI. These data support use of this presynchronization protocol to increase PR/ AI of lactating dairy cows receiving TAI compared with Ovsynch. PMID:15291005

  7. Metabolic Adaptation to Muscle Ischemia

    NASA Technical Reports Server (NTRS)

    Cabrera, Marco E.; Coon, Jennifer E.; Kalhan, Satish C.; Radhakrishnan, Krishnan; Saidel, Gerald M.; Stanley, William C.

    2000-01-01

    Although all tissues in the body can adapt to varying physiological/pathological conditions, muscle is the most adaptable. To understand the significance of cellular events and their role in controlling metabolic adaptations in complex physiological systems, it is necessary to link cellular and system levels by means of mechanistic computational models. The main objective of this work is to improve understanding of the regulation of energy metabolism during skeletal/cardiac muscle ischemia by combining in vivo experiments and quantitative models of metabolism. Our main focus is to investigate factors affecting lactate metabolism (e.g., NADH/NAD) and the inter-regulation between carbohydrate and fatty acid metabolism during a reduction in regional blood flow. A mechanistic mathematical model of energy metabolism has been developed to link cellular metabolic processes and their control mechanisms to tissue (skeletal muscle) and organ (heart) physiological responses. We applied this model to simulate the relationship between tissue oxygenation, redox state, and lactate metabolism in skeletal muscle. The model was validated using human data from published occlusion studies. Currently, we are investigating the difference in the responses to sudden vs. gradual onset ischemia in swine by combining in vivo experimental studies with computational models of myocardial energy metabolism during normal and ischemic conditions.

  8. 21 CFR 1210.12 - Physical examination of cows.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Physical examination of cows. 1210.12 Section 1210.12 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION REGULATIONS UNDER...

  9. 21 CFR 1210.12 - Physical examination of cows.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Physical examination of cows. 1210.12 Section 1210.12 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION REGULATIONS UNDER...

  10. 21 CFR 1210.12 - Physical examination of cows.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Physical examination of cows. 1210.12 Section 1210.12 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION REGULATIONS UNDER...

  11. Milk and manure: cows can energize U. S

    SciTech Connect

    Not Available

    1981-03-23

    The operation of a 180,000 gallon biogas digester on a 675 - cow dairy farm is briefly outlined. The gas, which is contained by a heavy plastic cover, is burned in a dual-fuel diesel engine to generate half the farm's electricity needs at about one-third the cost of commercial power.

  12. TRITIUM RETENTION BY COWS AND STEERS AND TRANSFER TO MILK

    EPA Science Inventory

    The report presents the results of an investigation designed to evaluate the short- and long-term behavior of tritium in beef animals and dairy cows with emphasis on the resultant hazard to humans consuming meat and dairy products. It is hoped that this information will be of use...

  13. A NEW CONCEPT IN RANGE COW SUPPLEMENT FORMULATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cattle grazing dormant New Mexico rangelands show yearly variation in response to supplementation. This reaction maybe partially due to differences in glucose (blood sugar) availability and metabolism, which maybe altered by forage conditions. Unlike people, cows absorb no sugar from their diet an...

  14. Effect of service sire and cow sire on gestation length

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent studies have examined environmental factors affecting gestation length (GL) and derived estimates of variance components for service sire and sire of daughters in heifers and cows. These studies show that bull differences exist, thus providing the opportunity to change GL. Predictors for Hols...

  15. 21 CFR 1210.12 - Physical examination of cows.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) REGULATIONS...REGULATIONS UNDER THE FEDERAL IMPORT MILK ACT Inspection and Testing...all cows in herds producing milk or cream which is to be...of the country in which such milk or cream is produced...

  16. Prevalence of Giardia duodenalis genotypes in adult dairy cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The prevalence of G. duodenalis genotypes was determined in adult dairy cows. Fecal specimens were collected from two farms each in Vermont, New York, Pennsylvania, Maryland, Virginia, North Carolina, and Florida. Specimens, cleaned of fecal debris and concentrated using CsCl density gradient centr...

  17. COWES: Clustering Web Users Based on Historical Web Sessions

    E-print Network

    Bhowmick, Sourav S.

    COWES: Clustering Web Users Based on Historical Web Sessions Ling Chen1,2 , Sourav S. Bhowmick1 Institute for Infocomm Research, Singapore, 119613 Abstract. Clustering web users is one of the most important research topics in web usage mining. Existing approaches cluster web users based on the snapshots

  18. Analysis of records of embryo production in Red Brahman cows 

    E-print Network

    Riano Rocha, Edgar Hernando

    2005-11-01

    Records of embryo production in Red Brahman donor cows (n=50) and F1 recipients (n=531) were evaluated from the collection day to the birth of the embryo produced. The effects of the sire of the donor and the embryo, protocol, season...

  19. A case of hypertrophic osteoarthropathy in a Belgian blue cow

    PubMed Central

    Guyot, Hugues; Sandersen, Charlotte; Rollin, Frédéric

    2011-01-01

    A 12-year-old cow was presented with chronic respiratory disease and lameness. Chronic pleuritis, pneumonia, and bronchial carcinoma were found as well as periosteal proliferation on limb bones. Ancillary tests and necropsy confirmed a combined pathology of pulmonary inflammation and neoplasm, and hypertrophic pulmonary osteopathy. PMID:22654134

  20. Influence of Exogenous Progestin on Ovarian Function in Beef Cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability to precisely regulate follicle recruitment and selection is critical to improving methods to control ovulation in beef cows. The objectives of the current study were to investigate the influence of exogenous progestins, commonly used in synchronization protocols, on ovarian function and...

  1. Grass tetany in a herd of beef cows

    PubMed Central

    2005-01-01

    Abstract Five cows in a herd of 15 cattle that had just been turned out onto lush pasture after having over-wintered on poor quality hay died suddenly. Biochemical profiles collected from the cadavers revealed reduced serum levels of magnesium, urea, and beta-hydroxybutycate. Classical grass tetany (hypomagnesemia) was diagnosed on postmortem examination. PMID:16187719

  2. Beef cow longevity and efficiency with limited feeding management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Feed consumed by the cowherd is a major cost of beef cattle production. Much of this cost is for harvested feed provided to supplement developing heifers and pregnant cows through periods when quality and quantity of rangeland forage may be limiting. An abundance of research concerning the influence...

  3. Cooperative Extension System Cow-Calf Management Library

    E-print Network

    O'Laughlin, Jay

    11 percent during April and May. Protein required for a 1,000-pound nonlactating cow is around 1 dietary crude protein is required. Drought ac- centuates the need for protein supplementation. Protein.0 percent of her body weight in forage daily. During drought, stocking rates may be adjusted to increase

  4. A longitudinal study of Giardia duodenalis genotypes in dairy cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fecal samples were collected from 30 dairy cows on the same farm beginning at 1 week of age and continuing for 2 years. Samples were collected weekly from 1 wk to 8 wks of age, bi-weekly from 2 mo to 6 mo of age and monthly thereafter. The samples were concentrated and cleaned of fecal debris on a...

  5. Toxic bovine mastitis caused by Staphylococcus aureus in twin cows.

    PubMed

    Rüegsegger; Corti; Sihto; Johler

    2014-11-01

    In this report, we describe two cases of bovine toxic mastitis associated with S. aureus and we provide DNA microarray based characterization data of the strain causing the disease. Both cows had recently calved and suffered from anorexia, pyrexia, and an elevated heart rate. In both animals, at least one mammary gland was swollen, hardened, sensitive to touch, and produced brownish or bloody secretions. The clinical state of the animals deteriorated quickly and both cows had to be euthanized within 48 hours after presentation. The S. aureus strain, which was isolated from the mastitis milk of both cows, was assigned to spa type t267, agr type I, capsule type 5 and CC97, a clonal complex recently identified as the evolutionary origin of two emerging clones of human epidemic community-associated methicillin-resistant S. aureus. The strain did not harbour any genes conferring resistance to antimicrobial agents and we did not detect any genes coding for enterotoxins, toxic shock syndrome toxin, or exfoliative toxins. Taking into consideration that twin cows were affected by this rare disease, we suggest that host factors may play a crucial role in toxic mastitis associated with S. aureus. PMID:25359115

  6. Sand impactions in a Saskatchewan beef cow-calf herd

    PubMed Central

    Erickson, Nathan; Hendrick, Steven

    2011-01-01

    Forty beef cows were reported to show signs of abdominal pain and discomfort over a period of 1 wk. Two of the affected animals died and on postmortem examination were found to be impacted with sand in their abomasum and small intestines. Sand-laden barley silage was found to be the cause of these impactions. PMID:21461212

  7. 21 CFR 1210.12 - Physical examination of cows.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Physical examination of cows. 1210.12 Section 1210.12 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION REGULATIONS UNDER THE FEDERAL IMPORT MILK ACT Inspection...

  8. Environmentally friendly cows–reducing our environmental hoof print

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of natural resources impacts the environment in five areas: 1) Energy, 2) Water, 3) Nutrients, 4) Greenhouse gases and 5) Biodiversity. The greatest opportunities for decreasing environmental impacts of the Holstein cow would seem to be enhancing utilization of nutrients and reducing emissio...

  9. Cows are thought to benefit from pasture, but does it really ma8er to the cow? Can pasture help lame cows recover? Will providing access to pasture result in lower milk produc>on?

    E-print Network

    Farrell, Anthony P.

    result in lower milk produc>on? Cows chose to spend >me on pasture and benefit to pasture also has no detrimental effects on milk produc>on. Preference The effects of pasture on cow preference, lameness and milk produc8on In one study, we provided

  10. Dairy cows use and prefer feed bunks fitted with sprinklers.

    PubMed

    Chen, Jennifer M; Schütz, Karin E; Tucker, Cassandra B

    2013-08-01

    Sprinklers reduce heat load in cattle, but elicit variable behavioral responses: cows readily use water in some studies, but in others either avoid it or show no preference. Nevertheless, on US dairies, a common way to cool cows is with nozzles mounted over the feed bunk that intermittently spray (i.e., 5 min on, 10 min off, as in this study) animals' backs while they feed. The objectives of this study were to determine how this type of sprinkler system affects behavior (single-treatment phase), and to assess preferences when cows were allowed to choose between feed bunks with or without sprinklers (choice phase). Data were collected 24h/d for lactating Holsteins tested in groups of 3 cows (n=8 groups) in warm ambient conditions [air temperature (mean ± standard deviation): 24-h average=24.5±2.5°C, maximum=36.0±3.5°C]. In the single-treatment phase, cows were fed from shaded bunks with or without sprinklers for 2 d/treatment, with order of exposure balanced in a crossover design. When sprinklers were present, cows spent more time at the bunk, both feeding [sprinkler vs. no sprinkler: 3.5 vs. 2.5h/24h, standard error (SE)=0.12h] and standing without feeding (4.3 vs. 2.3h/24h, SE=0.32 h) than when no sprinklers were present. Sprinklers lowered the average 24-h core temperature (38.8 vs. 39.2°C, SE=0.08°C), particularly on warmer days. Water cooling also mitigated the effects of weather on feeding time, which decreased with increasing heat load (air temperature and temperature-humidity index) when cows did not have sprinklers, but was unchanged when sprinklers were provided. In the choice phase, feed was provided ad libitum in both treatments for 5 d and preference was assessed. All groups preferred the feed bunk with sprinklers (78 vs. 22% of time spent near both feed bunks, SE=3.9%), and the magnitude of this preference increased linearly with heat load. In both phases of the study, cows protected their heads from direct spray when head position was elective (i.e., standing without feeding): cows were more likely to put their heads through the head gates when the sprinklers were on than off (single-treatment phase: 78 vs. 59%, respectively, of time spent standing without feeding, SE=2.8%; choice phase: 71 vs. 52%, SE=2.0%). In conclusion, although cows avoided wetting their heads, this is the first study to demonstrate that cattle readily use and clearly prefer sprinklers mounted above the feed bunk, possibly due to the cooling provided by this resource. PMID:23769371

  11. Is mad cow disease caused by a bacteria?

    PubMed

    Broxmeyer, L

    2004-01-01

    Transmissible spongioform enchephalopathies (TSE's), include bovine spongiform encephalopathy (also called BSE or "mad cow disease"), Creutzfeldt-Jakob disease (CJD) in humans, and scrapie in sheep. They remain a mystery, their cause hotly debated. But between 1994 and 1996, 12 people in England came down with CJD, the human form of mad cow, and all had eaten beef from suspect cows. Current mad cow diagnosis lies solely in the detection of late appearing "prions", an acronym for hypothesized, gene-less, misfolded proteins, somehow claimed to cause the disease. Yet laboratory preparations of prions contain other things, which could include unidentified bacteria or viruses. Furthermore, the rigors of prion purification alone, might, in and of themselves, have killed the causative virus or bacteria. Therefore, even if samples appear to infect animals, it is impossible to prove that prions are causative. Manuelidis found viral-like particles, which even when separated from prions, were responsible for spongiform STE's. Subsequently, Lasmezas's study showed that 55% of mice injected with cattle BSE, and who came down with disease, had no detectable prions. Still, incredibly, prions, are held as existing TSE dogma and Heino Dringer, who did pioneer work on their nature, candidly predicts "it will turn out that the prion concept is wrong." Many animals that die of spongiform TSE's never show evidence of misfolded proteins, and Dr. Frank Bastian, of Tulane, an authority, thinks the disorder is caused by the bacterial DNA he found in this group of diseases. Recently, Roels and Walravens isolated Mycobacterium bovis it from the brain of a cow with the clinical and histopathological signs of mad cow. Moreover, epidemiologic maps of the origins and peak incidence of BSE in the UK, suggestively match those of England's areas of highest bovine tuberculosis, the Southwest, where Britain's mad cow epidemic began. The neurotoxic potential for cow tuberculosis was shown in pre-1960 England, where one quarter of all tuberculous meningitis victims suffered from Mycobacterium bovis infection. And Harley's study showed pathology identical to "mad cow" from systemic M. bovis in cattle, causing a tuberculous spongiform encephalitis. In addition to M. bovis, Mycobacterium avium subspecies paratuberculosis (fowl tuberculosis) causes Johne's disease, a problem known and neglected in cattle and sheep for almost a century, and rapidly emerging as the disease of the new millennium. Not only has M. paratuberculosis been found in human Crohn's disease, but both Crohn's and Johne's both cross-react with the antigens of cattle paratuberculosis. Furthermore, central neurologic manifestations of Crohn's disease are not unknown. There is no known disease which better fits into what is occurring in Mad Cow and the spongiform enchephalopathies than bovine tuberculosis and its blood-brain barrier penetrating, virus-like, cell-wall-deficient forms. It is for these reasons that future research needs to be aimed in this direction. PMID:15325025

  12. Effects of Replacement of Concentrate Mixture by Broccoli Byproducts on Lactating Performance in Dairy Cows

    PubMed Central

    Yi, X. W.; Yang, F.; Liu, J. X.; Wang, J. K.

    2015-01-01

    The objective of the present study was to determine the effects of feeding pelletized broccoli byproducts (PBB) on milk yield and milk composition in dairy cows. In Trial 1, an in vitro gas test determined the optimal replacement level of PBB in a concentrate mixture in a mixed substrate with Chinese wild ryegrass hay (50:50, w/w) at levels of 0, 10%, 20%, 30%, or 40% (dry matter basis). When the concentrate was replaced by PBB at a level of 20%, no adverse effects were found on the gas volume or its rate constant during ruminal fermentation. In trial 2, 24 lactating cows (days in milk = 170.4±35; milk yield = 30±3 kg/d; body weight = 580 ±13 kg) were divided into 12 blocks based on day in milk and milk yield and randomly allocated to two dietary treatments: a basic diet with or without PBB replacing 20% of the concentrate mixture. The feeding trial lasted for 56 days; the first week allowed for adaptation to the diet. The milk composition was analyzed once a week. No significant difference in milk yield was observed between the two groups (23.5 vs 24.2 kg). A significant increase was found in milk fat content in the PBB group (p<0.05). Inclusion of PBB did not affect milk protein, lactose, total solids or solids-not-fat (p>0.05). These results indicated that PBB could be included in dairy cattle diets at a suitable level to replace concentrate mixture without any adverse effects on dairy performance. PMID:26323401

  13. Climate adaptation

    NASA Astrophysics Data System (ADS)

    Kinzig, Ann P.

    2015-03-01

    This paper is intended as a brief introduction to climate adaptation in a conference devoted otherwise to the physics of sustainable energy. Whereas mitigation involves measures to reduce the probability of a potential event, such as climate change, adaptation refers to actions that lessen the impact of climate change. Mitigation and adaptation differ in other ways as well. Adaptation does not necessarily have to be implemented immediately to be effective; it only needs to be in place before the threat arrives. Also, adaptation does not necessarily require global, coordinated action; many effective adaptation actions can be local. Some urban communities, because of land-use change and the urban heat-island effect, currently face changes similar to some expected under climate change, such as changes in water availability, heat-related morbidity, or changes in disease patterns. Concern over those impacts might motivate the implementation of measures that would also help in climate adaptation, despite skepticism among some policy makers about anthropogenic global warming. Studies of ancient civilizations in the southwestern US lends some insight into factors that may or may not be important to successful adaptation.

  14. Physiology of vitreous surgery.

    PubMed

    Stefánsson, Einar

    2009-02-01

    Vitreous surgery has various physiological and clinical consequences, both beneficial and harmful. Vitrectomy reduces the risk of retinal neovascularization, while increasing the risk of iris neovascularization, reduces macular edema and stimulates cataract formation. These clinical consequences may be understood with the help of classical laws of physics and physiology. The laws of Fick, Stokes-Einstein and Hagen-Poiseuille state that molecular transport by diffusion or convection is inversely related to the viscosity of the medium. When the vitreous gel is replaced with less viscous saline, the transport of all molecules, including oxygen and cytokines, is facilitated. Oxygen transport to ischemic retinal areas is improved, as is clearance of VEGF and other cytokines from these areas, thus reducing edema and neovascularization. At the same time, oxygen is transported faster down a concentration gradient from the anterior to the posterior segment, while VEGF moves in the opposite direction, making the anterior segment less oxygenated and with more VEGF, stimulating iris neovascularization. Silicone oil is the exception that proves the rule: it is more viscous than vitreous humour, re-establishes the transport barrier to oxygen and VEGF, and reduces the risk for iris neovascularization in the vitrectomized-lentectomized eye. Modern vitreous surgery involves a variety of treatment options in addition to vitrectomy itself, such as photocoagulation, anti-VEGF drugs, intravitreal steroids and release of vitreoretinal traction. A full understanding of these treatment modalities allows sensible combination of treatment options. Retinal photocoagulation has repeatedly been shown to improve retinal oxygenation, as does vitrectomy. Oxygen naturally reduces VEGF production and improves retinal hemodynamics. The VEGF-lowering effect of photocoagulation and vitrectomy can be augmented with anti-VEGF drugs and the permeability effect of VEGF reduced with corticosteroids. Starling's law explains vasogenic edema, which is controlled by osmotic and hydrostatic gradients between vessel and tissue. It explains the effect of VEGF-induced vascular permeability changes on plasma protein leakage and the osmotic gradient between vessel and tissue. At the same time, it takes into account hemodynamic changes that affect the hydrostatic gradient. This includes the influence of arterial blood pressure, and the effect oxygen (laser treatment) has in constricting retinal arterioles, increasing their resistance, and thus reducing the hydrostatic pressure in the microcirculation. Reduced capillary hydrostatic pressure and increased osmotic gradient reduce water fluxes from vessel to tissue and reduce edema. Finally, Newton's third law explains that vitreoretinal traction decreases hydrostatic tissue pressure in the retina, increases the pressure gradient between vessel and tissue, and stimulates water fluxes from vessel into tissue, leading to edema. PMID:19034481

  15. Physiological skin changes during pregnancy.

    PubMed

    Tyler, Kelly H

    2015-03-01

    Physicians may often mistake normal physiological skin changes in pregnancy for pathologic changes, so being able to recognize the skin manifestations unique to pregnancy is of the utmost importance to avoid unnecessary testing and stress for the obstetric patient. Most physiological skin changes will resolve postpartum, so reassurance and expectant management is indicated in almost all cases. PMID:25517755

  16. Folic acid supplemented goat milk has beneficial effects on hepatic physiology, haematological status and antioxidant defence during chronic Fe repletion.

    PubMed

    Alférez, María J M; Rivas, Emilio; Díaz-Castro, Javier; Hijano, Silvia; Nestares, Teresa; Moreno, Miguel; Campos, Margarita S; Serrano-Reina, Jose A; López-Aliaga, Inmaculada

    2015-02-01

    The aim of the current study was to asses the effect of goat or cow milk-based diets, either normal or Fe-overloaded and folic acid supplement on some aspects of hepatic physiology, enzymatic antioxidant defence and lipid peroxidation in liver, brain and erythrocyte of control and anaemic rats after chronic Fe repletion. 160 male Wistar rats were placed on 40 d in two groups, a control group receiving normal-Fe diet and the Fe-deficient group receiving low Fe diet. Lately, the rats were fed with goat and cow milk-based diets during 30 d, with normal-Fe content or Fe-overload and either with normal folic or folic acid supplemented. Fe-overload increased plasma alanine transaminase and aspartate transaminase levels when cow milk was supplied. Dietary folate supplementation reduced plasma transaminases levels in animals fed goat milk with chronic Fe overload. A remarkable increase in the superoxide dismutase activity was observed in the animals fed cow milk. Dietary folate supplement lead to a decrease on the activity of this enzyme in all the tissues studied with both milk-based diets. A concomitant increment in catalase was also observed. The increase in lipid peroxidation products levels in rats fed cow milk with Fe-overload, suggest an imbalance in the functioning of the enzymatic antioxidant defence. In conclusion, dietary folate-supplemented goat milk reduces both plasma transaminases levels, suggesting a hepatoprotective effect and has beneficial effects in situation of Fe-overload, improving the antioxidant enzymes activities and reducing lipid peroxidation. PMID:25394837

  17. Early pregnancy diagnosis in dairy cows using circulating nucleic acids.

    PubMed

    Mayer, Jennifer; Soller, Jan T; Beck, Julia; Purwins, Vanessa; Wemheuer, Wilhelm; Schütz, Ekkehard; Brenig, Bertram

    2013-01-01

    Early and accurate pregnancy diagnosis in dairy cattle is a prerequisite for successful herd management. However, most of the currently available methods allow an early diagnosis only approximately 30 days after insemination. Recently, circulating nucleic acids (CNAs) have been used successfully as biomarkers in prenatal diagnosis at different gestational stages in human and animals. Here we show that CNAs can also be used as markers for the detection of early pregnancy in cattle. Serum samples were collected from multiparous pregnant (N = 24) and nonpregnant (N = 16) dairy cows at different days after insemination (Days 0, 20, and 40). Isolated serum DNA was preprocessed using a modified serial analysis of gene expression technique, which generated concatemerized short sequence tags for downstream next generation sequencing. Bioinformatic analysis identified sequence tags specific for pregnant dairy cows at Day 20 after insemination. The identified CNA-tags originated from repetitive regions of the bovine genome. Tag sequences that showed increased hit counts per animal were used to design quantitative real-time polymerase chain reaction assays. These quantitative polymerase chain reaction assays were applied to CNA samples from matched pregnant (N = 12) and nonpregnant cows (N = 16) at different times after insemination (Day 0, 20, and 40). At Day 20 after insemination the quantities of the interspersed repeats Art2A and BovB were increased in the pregnant cows compared with the nonpregnant control cows (P < 0.05). The best performing CNA biomarker BovB yielded an area under the receiver operating characteristic curve of 0.76. At a defined cutoff value, the pregnant and the control groups can be distinguished with a sensitivity of 83% and specificity of 75%. These results suggest that CNAs can be used as biomarkers for the detection of early pregnancy in cattle. PMID:23122603

  18. Genetic regulation of prepartum dry matter intake in Holstein cows.

    PubMed

    Shonka, B N; Tao, S; Dahl, G E; Spurlock, D M

    2015-11-01

    The objective of this study was to estimate genetic parameters for dry matter intake (DMI) in prepartum nonlactating and in lactating Holstein cows. Measurements were recorded on cows from Iowa State University (ISU) and the University of Florida (UF) dairy herds. Individual feed intake data were recorded daily at ISU from approximately 30d prepartum through 150d in milk (DIM). Individual intakes from cows at UF were recorded for approximately 42d pre- and postpartum. Prepartum DMI traits were defined as DMI on d -15 (multiparous) or d -8 (primiparous) relative to calving date (DRYDMI), DMI on d -1 before parturition (CALVEDMI), and the negative of the slope of a regression line fitted through the last 14 (multiparous) or 7 (primiparous) days before calving (DEC). Lactation DMI traits were defined as DMI at 30 DIM (DMI30) and 100 DIM (DMI100; ISU data only). The final data set included 245 primiparous and 221 multiparous cows from ISU, and 125 multiparous cows from UF. Heritability estimates were 0.43, 0.64, 0.32, and 0.62 for DRYDMI, CALVEDMI, DEC, and DMI30, respectively. The estimate of heritability for DMI100 (ISU only) was 0.52. The genetic correlation between DRYDMI and DMI30 was 0.97. Thus, DMI prepartum is a moderately heritable trait that is highly correlated with intake during early lactation. Genetic correlations between DEC and DMI during lactation were lower and similar to standard error estimates (-0.24±0.22 for DEC and DMI30 for combined data, and -0.13±0.27 for DEC and DMI100 in ISU data). Thus, selection for altered DMI during lactation may not dramatically affect the depression in intake that occurs before parturition. PMID:26319760

  19. Physiological correlates of mental workload

    NASA Technical Reports Server (NTRS)

    Zacharias, G. L.

    1980-01-01

    A literature review was conducted to assess the basis of and techniques for physiological assessment of mental workload. The study findings reviewed had shortcomings involving one or more of the following basic problems: (1) physiologic arousal can be easily driven by nonworkload factors, confounding any proposed metric; (2) the profound absence of underlying physiologic models has promulgated a multiplicity of seemingly arbitrary signal processing techniques; (3) the unspecified multidimensional nature of physiological "state" has given rise to a broad spectrum of competing noncommensurate metrics; and (4) the lack of an adequate definition of workload compels physiologic correlations to suffer either from the vagueness of implicit workload measures or from the variance of explicit subjective assessments. Using specific studies as examples, two basic signal processing/data reduction techniques in current use, time and ensemble averaging are discussed.

  20. Establishing common course objectives for undergraduate exercise physiology.

    PubMed

    Simonson, Shawn R

    2015-12-01

    Undergraduate exercise physiology is a ubiquitous course in undergraduate kinesiology/exercise science programs with a broad scope and depth of topics. It is valuable to explore what is taught within this course. The purpose of the present study was to facilitate an understanding of what instructors teach in undergraduate exercise physiology, how it compares with various guidelines, and to continue the conversation regarding what should be taught. A survey was created using course outcomes from the American Society of Exercise Physiologists, National Association for Sport and Physical Education, Ivy's 2007 Quest article, the National Athletic Training Association, the National Council for Accreditation of Teacher Education, and 36 undergraduate exercise physiology course syllabi. The 134-item survey was disseminated to individuals who use exercise physiology: university faculty members, clinical exercise physiologists, researchers, and other practitioners on various exercise physiology lists; 2,009 surveys were sent, and 322 surveys were completed (16% rate of return). There was a high degree of agreement about a lot of important content in undergraduate exercise physiology. Instructors of exercise physiology should focus their curriculum on regulation and homeostasis (including adaptation, fatigue, and recovery), aerobic systems, bioenergetics, muscle physiology, and fitness principles. In addition, attention should be paid to performance and technical skills. In conclusion, it is up to exercise physiologists to ensure quality of knowledge and practice. Doing so will improve the uniformity and quality of practitioners within the various kinesiology/exercise science fields and increase the value of a Kinesiology/Exercise Science degree and set it apart from other healthcare providers and fitness professionals. PMID:26628652