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1

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...

2

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,...

3

Physiological Adaptation in Desert Birds  

NSDL National Science Digital Library

This peer-reviewed article from BioScience journal is about adaptations desert birds. We call into question the idea that birds have not evolved unique physiological adaptations to desert environments. The rate at which desert larks metabolize energy is lower than in mesic species within the same family, and this lower rate of living translates into a lower overall energy requirement in the wild. We argue that selection has reduced oxygen consumption at the tissue level under basal conditions for birds living in deserts. We document that total evaporative water loss--the sum of cutaneous water loss (CWL) and respiratory water loss--is reduced in desert birds, and present evidence that changes in CWL are responsible for this pattern. The diminution in CWL is attributable to changes in the lipid structure of the stratum corneum of the skin, the physical barrier to diffusion of water vapor. Finally, we show linkages between physiology and life-history attributes of larks along an aridity gradient; birds from deserts have not only a reduced rate of metabolism but also a small clutch size and slow nestling development. Hence, attributes of physiology are correlated with traits that directly affect reproductive success. Our hope is that we will prompt students to question the notion that birds do not possess physiological adaptations to the desert environment, and raise the specter of doubt about "preadaptation" in birds living in deserts.

JOSEPH B. WILLIAMS and B. IRENE TIELEMAN (; )

2005-05-01

4

Exercise Physiology Ethnic Differences in Physiological Cardiac Adaptation to  

E-print Network

Exercise Physiology Ethnic Differences in Physiological Cardiac Adaptation to Intense Physical Exercise in Highly Trained Female Athletes J. Rawlins, MRCP; F. Carre, PhD; G. Kervio, PhD; M. Papadakis exercise in black female athletes is associated with greater left ventricular hypertrophy and higher

Boyer, Edmond

5

Perspective on physiological/endocrine and nutritional factors influencing fertility in post-partum dairy cows.  

PubMed

Increasing reproductive performance of post-partum lactating dairy cows is a multi-factorial challenge involving disciplines of production medicine, nutrition, physiology and herd management. Systems of programmed timed insemination have been fine-tuned to achieve pregnancy per artificial inseminations (AI) approximating 45%. Systems have optimized follicle development, integrated follicle development with timing of induced corpus luteum regression and fine-tuned sequential timing of induced ovulation and AI. Use of programmes for insemination have identified occurrence of anovulatory ovarian status, body condition, uterine health and seasonal summer stress as factors contributing to reduced herd fertility. Furthermore, programmes of timed insemination provide a platform to evaluate efficacy of nutritional and herd health systems targeted to the transition and post-partum periods. The homeorhetic periparturient period, as cows deal with decreases in dry matter intake, results in a negative energy balance and is associated with a period of immunosuppression. Cows that transition well will cycle earlier and have a greater risk of becoming pregnant earlier post-partum. The innate arms of the immune system (acute and adaptive) are suppressed during the periparturient period. Cows experiencing the sequential complex of disorders such as dystocia, puerperal metritis, metritis, endometritis and subclinical endometritis are subsequently less fertile. Targeted strategies of providing specific nutraceuticals that provide pro- and anti-inflammatory effects, such as polyunsaturated fatty acids (e.g., linoleic, eicosapentaenoic/docosahexaenoic, conjugated linoleic acid), sequential glycogenic and lipogenic enrichment of diets, and organic selenium appear to differentially regulate and improve the immune and reproductive systems to benefit an earlier restoration of ovarian activity and increased fertility. PMID:24417194

Thatcher, W W; Santos, J E P; Silvestre, F T; Kim, I H; Staples, C R

2010-09-01

6

Addition of Sodium Bicarbonate to Rations of Postpartum Dairy Cows: Physiological and Metabolic Effects1  

Microsoft Academic Search

Sodium bicarbonate was added to complete mixed rations to characterize physiological, metabolic, and ruminal changes immediately postpartum when dairy cows are switched abruptly from a low energy ration prepartum to a high energy ration postpartum. Twelve Holstein cows were paired and assigned randomly to either a control or buffered ration containing .8% sodium bicarbonate. Ra- tions consisted of 50% corn

L. H. Kilmer; L. D. Muller; T. J. Snyder

1981-01-01

7

Physiologic adaptation to space - Space adaptation syndrome  

NASA Technical Reports Server (NTRS)

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.

Vanderploeg, J. M.

1985-01-01

8

Individual differences in behavioral and physiological responsiveness of primiparous dairy cows to machine milking  

Microsoft Academic Search

An experiment was performed in primiparous dairy cows (n = 23) to examine consistency of individual differences in reactivity to milking, and correlations between measures of behavior, physiology, and milk ejection. Responsiveness to milking was monitored during the first machine milking, on d 2 of lactation, and during milkings on d 4 and 130 of lactation. Measurements included kicking and

Reenen van C. G; Werf van der J. T. N; R. M. Bruckmaier; H. Hopster; B. Engel; J. P. T. M. Noordhuizen; H. J. Blokhuis

2002-01-01

9

PHYSIOLOGY OF THE NEWBORN AND ITS ADAPTATION TO THE ENVIRONMENT  

E-print Network

Session 1 PHYSIOLOGY OF THE NEWBORN AND ITS ADAPTATION TO THE ENVIRONMENT INTRODUCTION R. JARRIGE. At delivery, the fetus is required to undergo major changes in its physiology and anatomy in order to adapt is to outline the main aspects of newborn physiology and its adap- tation to the aerial environment

Paris-Sud XI, Université de

10

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

ERIC Educational Resources Information Center

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)

Fleck, Steven J.; Kraemer, William J.

1988-01-01

11

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

NASA Astrophysics Data System (ADS)

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.

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

2005-11-01

12

Theoretical and semantic aspects of the modular physiological adaptation.  

PubMed

Adaptation is a fundamental concept in biology. The use of this notion in physiology presents a special problem, on the one hand, due to its widespread application to practically all physiologic phenomena of organic economy, on the other hand, because there is no formal definition providing a demarcation between adaptive processes and secondary processes without relating them with adaptation. Therefore, the objective of this work is to formalize a modular definition of adaptation that allows a differentiation between adaptive processes and non adaptive ones. I conclude that the use of the concept of 'module' in the definition of adaptation makes it possible to demarcate adaptive processes. Furthermore, the proposed definition lets us eliminate the use of notions such as those of 'features' and 'characteristics' and solve a methodological problem encountered at organizational levels. PMID:16180196

Dressino, Vicente

2005-01-01

13

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

PubMed

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

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

2014-12-01

14

Effect of induced subclinical hypocalcemia on physiological responses and neutrophil function in dairy cows.  

PubMed

The objectives were to study the effects of induced subclinical hypocalcemia [SCH, blood ionized Ca (iCa(2+)) <1.0mM, without recumbency] on physiological responses and function of immune cells in dairy cows. Ten nonpregnant, nonlactating Holstein cows were blocked by lactation and assigned randomly to a normocalcemic (NC; intravenous infusion of 0.9% NaCl i.v. plus 43 g of oral Ca, as Ca sulfate and Ca chloride, at -1 and 11h) or an induced SCH [SCHI, 5% ethylene glycol tetraacetic acid (EGTA), a selective iCa(2+) chelator, intravenous infusion] treatment for 24h, using a crossover design. The sequence of treatments was either NC-SCHI or SCHI-NC, with a 6-d washout period. Ionized Ca was evaluated before, hourly during the infusion period, and at 48 and 72 h, to monitor concentrations and adjust the rate of infusion, maintaining blood iCa(2+) <1.0mM in SCHI throughout the 24-h infusion period. Additional measurements included heart and respiratory rates, rectal temperature, dry matter intake, rumen contractions, whole-blood pH, concentrations of glucose and K in whole blood, concentrations of total Ca, Mg, nonesterified fatty acids, ?-hydroxybutyrate, and insulin in plasma, and urinary excretion of Ca. Total and differential leukocyte count in blood was also performed. The concentration of cytosolic iCa(2+) in neutrophils and lymphocytes was quantified and neutrophil function was assayed in vitro. Infusion of a 5% EGTA solution successfully induced SCH in all SCHI cows, resulting in decreased blood iCa(2+) concentrations throughout the 24-h treatment period (0.77 ± 0.01 vs. 1.26 ± 0.01 mM iCa(2+)). Induction of SCH reduced dry matter intake on the day of infusion (5.3 ± 0.8 vs. 9.1 ± 0.8 kg/d) and rumen contractions (1.9 ± 0.2 vs. 2.7 ± 0.2 contractions/2 min) for the last 12h of infusion. Cows in SCHI had decreased plasma insulin concentration (1.44 ± 0.23 vs. 2.32 ± 0.23 ng/mL) evident between 6 and 18 h after the beginning of the infusion, accompanied by increased concentrations of glucose (4.40 ± 0.04 vs. 4.17 ± 0.04 mM). Plasma nonesterified fatty acids concentration was greater for SCHI than NC cows (0.110 ± 0.019 vs. 0.061 ± 0.014 mM). Neutrophils of cows in SCHI had a faster decrease in cytosolic iCa(2+) after stimulation with ionomycin (9.9 ± 1.0 vs. 13.6 ± 1.4 Fluo-4:Fura Red post-end ratio) in vitro. Furthermore, induction of SCH reduced the percentage of neutrophils undergoing phagocytosis (22.1 ± 2.1 vs. 29.3 ± 2.1%) and reduced the oxidative burst response after incubation of pathogenic bacteria (16.1 ± 1.7 vs. 24.2 ± 1.7%). Subclinical hypocalcemia compromised appetite, altered metabolism, and impaired function of immune cells in dairy cows. PMID:24359833

Martinez, N; Sinedino, L D P; Bisinotto, R S; Ribeiro, E S; Gomes, G C; Lima, F S; Greco, L F; Risco, C A; Galvão, K N; Taylor-Rodriguez, D; Driver, J P; Thatcher, W W; Santos, J E P

2014-02-01

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

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...

17

Adaptive Canceling of Physiological Tremor for Improved Precision in Microsurgery  

Microsoft Academic Search

Physiological hand tremor impedes microsurgery. We present both a novel adaptive algorithm for tremor estimation and a new technique for active real-time canceling of physio- logical tremor. Tremor is modeled online using the weighted- frequency Fourier linear combiner (WFLC). This adaptive al- gorithm models tremor as a modulating sinusoid, and tracks its frequency, amplitude, and phase. Piezoelectric actuators move the

Cameron N. Riviere; R. Scott Rader; Nitish V. Thakor

1998-01-01

18

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

PubMed

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

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

19

Physiological Self-Regulation and Adaptive Automation  

NASA Technical Reports Server (NTRS)

Adaptive automation has been proposed as a solution to current problems of human-automation interaction. Past research has shown the potential of this advanced form of automation to enhance pilot engagement and lower cognitive workload. However, there have been concerns voiced regarding issues, such as automation surprises, associated with the use of adaptive automation. This study examined the use of psychophysiological self-regulation training with adaptive automation that may help pilots deal with these problems through the enhancement of cognitive resource management skills. Eighteen participants were assigned to 3 groups (self-regulation training, false feedback, and control) and performed resource management, monitoring, and tracking tasks from the Multiple Attribute Task Battery. The tracking task was cycled between 3 levels of task difficulty (automatic, adaptive aiding, manual) on the basis of the electroencephalogram-derived engagement index. The other two tasks remained in automatic mode that had a single automation failure. Those participants who had received self-regulation training performed significantly better and reported lower National Aeronautics and Space Administration Task Load Index scores than participants in the false feedback and control groups. The theoretical and practical implications of these results for adaptive automation are discussed.

Prinzell, Lawrence J.; Pope, Alan T.; Freeman, Frederick G.

2007-01-01

20

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, A. F. 1997. Adaptation and the evolution of physiological characters,pp. 3-16. In: Handbook of Physiology, Sect. 13: Comparative Physiology. W. H. Dantzler, ed. Oxford Univ. Press, New York. 1. Adaptation and the evolution of physiological characters A L B E R T F. B E N N E T T 1

Bennett, Albert F.

21

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

PubMed

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

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

2006-05-01

22

Nociceptive threshold, blood constituents and physiological values in 213 cows with locomotion scores ranging from normal to severely lame.  

PubMed

The aim of this study was to investigate associations between mechanical nociceptive threshold, blood constituents, physiological measurements and locomotion score (LS) in dairy cattle with a range of LS from 1 (normal) to 5 (severely lame). The study used 213 Friesian/Friesian cross dairy cows from 12 farms. There were 40-50 cows each with LS 1-4 and 22 cows with LS 5. Each cow was restrained and her temperature and respiratory and cardiac rates were measured. Nociceptive threshold, plasma concentrations of haptoglobin, ?-hydroxybutyrate (?-HB), cortisol, glucose, lactate, creatinine kinase activity, packed cell volume and white blood cell counts were determined. Mixed effect models were used to investigate associations between the variables measured and LS. Parity and stage of lactation were forced into all analyses and the model fit was checked by investigation of residuals. After accounting for parity and stage of lactation, nociceptive threshold was significantly lower in cattle with LS 3-5 compared with LS 1 in a dose response manner, indicating increasing hyperalgesia with increasing LS. Haptoglobin concentration was raised in all cattle with LS>1, demonstrating an inflammatory response with all levels of lameness. Cortisol and glucose concentrations were lower and ?-HB concentrations higher in cows with LS 2 compared with cows with other scores, possibly signifying metabolic challenge. Heart and respiratory rate and rectal temperature were significantly higher only in cows with LS 5, suggesting that these measurements were insensitive measures of pain or stress. It was concluded that hyperalgesia increases with increasing severity of lameness and that nociceptive pressure and haptoglobin were sensitive measures of pain from lameness. PMID:23499542

Tadich, N; Tejeda, C; Bastias, S; Rosenfeld, C; Green, L E

2013-08-01

23

Psychological and Physiological Adaptations to Sperm Competition in Humans  

Microsoft Academic Search

Postcopulatory competition between males, in the form of sperm competition, is a widespread phenomenon in many animal species. The extent to which sperm competition has been an important selective pressure during human evolution remains controversial, however. The authors review critically the evidence that human males and females have psychological, behavioral, and physiological adaptations that evolved in response to selection pressures

Todd K. Shackelford; Nicholas Pound; Aaron T. Goetz

2005-01-01

24

Coping with Thermal Challenges: Physiological Adaptations to Environmental Temperatures  

E-print Network

in animals, primarily due to the ef- fects on biochemical reaction rates. Since physiological responses are often exemplified by their rate dependency (e.g., rate of blood flow, rate of metabolism, rate of heat production, and rate of ion pumping), the study of temperature adaptations has a long history in comparative

Tattersall, Glenn

25

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

PubMed

Progesterone treatments are used to increase submission rates in postpartum dairy cows; however, in many cases the protocol is used as a blanket therapy for all cows without regard for physiological or disease state. The objective of this study was to identify the physiological or disease classes of cows that respond well (or not) to synchronization of estrus via progesterone. Dairy cows (n = 402) were monitored peri and postpartum to establish their physiological or disease status. Animals were classified as having negative energy balance, clinical lameness, uterine infection (UI), anovulatory anestrus, high somatic cell counts, and healthy (H). Blood samples were collected at five different time points and analyzed for metabolites. All animals received an 8-day controlled internal drug release protocol, which included GnRH at insertion and PGF2? the day before removal. Response to the protocol was determined by visual observation of estrus synchronization. Conception rate was determined by ultrasonography between Days 32 and 35 after artificial insemination. Animals without UI were 1.9 times more likely to respond and two times more likely to be confirmed pregnant than those with UI. There was no relationship between negative energy balance and clinical lameness in the visual estrous response, but both conditions were associated with reduced conception rates. Dairy cows in anovulatory anestrus responded successfully to the protocol in both estrous response and conception rates. High glutathione peroxidase concentrations had a positive effect on conception rates, whereas high non-esterified fatty acids and beta-hydroxybutyrate had a negative effect on the estrous response. In conclusion, disease and physiological states of dairy cows determined the response to progesterone-based synchronization. The more disease or physiological problems the cows had, the lower the estrous response and conception rates; cows with these problems were not ideal candidates for synchronization. Both anestrus and healthy dairy cows were good responders to progesterone-based synchronization. PMID:25261264

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

2014-12-01

26

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...

27

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

NASA Astrophysics Data System (ADS)

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.

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

2015-02-01

28

Energy and lipid metabolism gene expression of D18 embryos in dairy cows is related to dam physiological status.  

PubMed

We analyzed the change in gene expression related to dam physiological status in day (D)18 embryos from growing heifers (GH), early lactating cows (ELC), and late lactating cows (LLC). Dam energy metabolism was characterized by measurement of circulating concentrations of insulin, glucose, IGF-1, nonesterified fatty acids, ?-hydroxybutyrate, and urea before embryo flush. The metabolic parameters were related to differential gene expression in the extraembryonic tissues by correlation analysis. Embryo development estimated by measuring the length of the conceptuses and the proportion of expected D18 gastrulating stages was not different between the three groups of females. However, embryo metabolism was greatly affected by dam physiological status when we compared GH with ELC and GH with LLC but to a lesser extent when ELC was compared with LLC. Genes involved in glucose, pyruvate, and acetate utilization were upregulated in GH vs. ELC conceptuses (e.g., SLC2A1, PC, ACSS2, ACSS3). This was also true for the pentose pathway ( PGD, TKT), which is involved in synthesis of ribose precursors of RNA and DNA. The pathways involved in lipid synthesis were also upregulated in GH vs. ELC. Despite similar morphological development, the molecular characteristics of the heifers' embryos were consistently different from those of the cows. Most of these differences were strongly related to metabolic/hormone patterns before insemination and during conceptus free-life. Many biosynthetic pathways appeared to be more active in heifer embryos than in cow embryos, and consequently they seemed to be healthier, and this may be more conducive to continue development. PMID:24220328

Valour, D; Degrelle, S A; Ponter, A A; Giraud-Delville, C; Campion, E; Guyader-Joly, C; Richard, C; Constant, F; Humblot, P; Ponsart, C; Hue, I; Grimard, B

2014-01-15

29

Morpho-physiological traits characterizing environmental adaptation of Avena barbata  

Microsoft Academic Search

Seventeen morphological and physiological characteristics of three Avena barbata L. populations from Israel were measured\\u000a in order to define possible combinations explaining adaptation of these populations to different precipitation, temperature\\u000a and altitude regimes. Five genotypes from each A. barbata populations were collected from Ashqelon (31°63?N, low annual precipitation),\\u000a En Hamifraz (32°46?N, high temperature), and Mount Carmel (32°73?N, high altitude), Israel.

Susanne Somersalo; Pirjo Mäkelä; Ari Rajala; Eviatar Nevo; Pirjo Peltonen-Sainio

1998-01-01

30

Physiological responses in thermal stressed Jersey cows subjected to different management strategies.  

PubMed

The effects of cooling and recombinant bovine somatotropin (rbST) on milk yield, reproductive performance, and health of Jersey cattle during summer thermal stress were measured for 2 yr. Cows were assigned to one of two groups based upon days in milk (DIM), parity, and genetic index. Year 1 and year 2 control cows (n = 143, n = 183, respectively) were housed in a pen with only shades. Cooled treatment cows each year (n = 142, n = 180) were housed with a spray and fan system for evaporative cooling. Cows were assigned at various days postpartum, not before d 63, coincident with commencement of rbST injections. One half of cows in each group received rbST on d 63 postpartum. Cows were assigned to the shade trial ranging from d 63 to 190. Cooled versus noncooled DIM were similar at the start of the trial. Trials began on July 1, 1999, and July 1, 2000, and concluded on September 30, 1999, and September 25, 2000. The ANOVA of daily milk weight data was conducted utilizing a 2 x 2 factorial design with cooling and rbST treatments as main effects. Cooling in combination with rbST increased milk yield compared with no cooling and no rbST for 1999 and 2000 (25.5 versus 21.8 kg/d, and 23.7 versus 20.5 kg/d, respectively). In general, cooling improved health and reproductive performance. PMID:12512595

Keister, Z O; Moss, K D; Zhang, H M; Teegerstrom, T; Edling, R A; Collier, R J; Ax, R L

2002-12-01

31

Aspects of physiological effects of sodium zeolite A supplementation in dry, non-pregnant dairy cows fed grass silage.  

PubMed

The objective of the present study was to monitor serum and urine biochemical changes in dairy cows during and after oral administration of a synthetic sodium aluminium-silicate (zeolite A). A prospective longitudinal study involving four non-pregnant and non-lactating cows was chosen. Cows were randomly allocated to either a control or experimental group. The period of observation was three weeks. During the first week (period 1) cows were maintained on basic ration for the purpose of recording baseline values. During the second week (period 2) control cows were fed a basic diet (grass silage), while cows in the experimental group were fed the basic diet and supplemented with 1 kg zeolite pellets once daily. During the third week (period 3) both groups were fed the basic ration only and observed for any persistent effects after zeolite withdraw. Daily sampling included blood and urine. Selected physiological parameters were compared between groups during period 2 and 3, whereas mean values from period 1, 2 and 3 were compared within the groups. Zeolite supplementation revealed a significant influence on calcium homeostasis. A slight decrease in serum Ca and in renal excretion of calcium was observed in the experimental group at initiation of supplementation, whereas an increment in these parameters was recorded after withdrawal of zeolite supplementation. It is assumed, that zeolite caused a reduction in the availability of dietary calcium during supplementation, which possibly elicited an activation of calcium mobilisation. The influence of zeolite on calcium homeostasis was not evident from monitoring serum concentration of calcium regulating hormones (PTH, 1,25(OH)2D3, 25(OH)VitD) or renal excretion of markers of bone resorption. Enhanced active intestinal calcium absorption and bone resorption was therefore considered insignificant in the calcium mobilisation under the conditions of this experiment. The origin of the increased amount of Ca, which was observed in serum and urine after zeolite withdraw, is at present unknown, but it is suggested, that the readily mobilized Ca-pool in bone was a contributing factor. An effect of zeolite on phosphate and magnesium homeostasis in the experimental group was evidenced from the values of serum concentration and fractional excretion, which during supplementation were significant lower than in the control group. The influence of zeolite on phosphorus and magnesium is presumed to result from a combination of interference of zeolite with intestinal absorption and a marginal dietary supplementation of these minerals. PMID:14621401

Enemark, J M; Frandsen, A M; Thilsing-Hansen, T; Jørgensen, R J

2003-01-01

32

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

PubMed

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

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

2015-02-01

33

Physiological adaptations of small mammals to desert ecosystems.  

PubMed

Adaptations of animals to the xeric environment have been studied in various taxonomic groups and across several deserts. Despite the impressive data that have been accumulated, the focus in most of these studies is mainly on the significance of one variable at a time. Here, we attempt to integrate between responses of several physiological systems, challenged by increasing diet and water salinity and extreme temperatures, acquired in different studies of thermo and osmo-regulatory adaptations, of small rodents, to the xeric environment. Studies have shown differential thermoregulatory responses to increased dietary salinity, which were attributed to habitat and habits of the relevant species. In the thermoregulatory studies, a potential adaptive significance of low metabolic rate was demonstrated. From an evolutionary point of view, the most important adaptation is in the timing of reproduction, as it enables the transfer of genetic properties to the next generation in an unpredictable ecosystem, where reproduction might not occur every year. Results in this aspect show that increased dietary salinity, through an increase in vasopressin plasma levels, plays an important role as a regulator of the reproductive system. We assume that the amount of food existing in the habitat and the amount of reserves in the animal in the form of white adipose tissue are important for reproduction. Photoperiod affects all studied physiological responses, emphasizing the importance of pre-acclimation to seasonal characteristics. We summarize the existing data and suggest neuro-endocrine pathways, which have a central role in these adaptations by affecting thermoregulation, osmoregulation and reproduction to create the optimal response to xeric conditions. These hypotheses can be used as the basis for future studies. PMID:21392308

Schwimmer, Hagit; Haim, Abraham

2009-12-01

34

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

PubMed

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

Calfapietra, Carlo; Peñuelas, Josep; Niinemets, Ülo

2015-02-01

35

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)

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.

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

36

Effects of Drinking Water Temperature on Physiological Responses of Lactating Holstein Cows in Summer1  

Microsoft Academic Search

Nine Iactating Holstein cows were offered drinking water of 7.2, 15.6, and 23.9°C in a 3 x 3 Latin square design in Experiment 1. Water was offered for 10 min at 1300 h to simulate time in a milking parlor. Water consumption de- clined as drinking water temperature decreased. Respiration rates decreased as the drinking water temperature decreased. In Experiment

J. Ko LANHAM; C. E. Coppock; K. Z. Milam; J. M. Labore; D. H. Nave; R. A. Stermer; C. F. Brasington

1986-01-01

37

Membrane lipid unsaturation as physiological adaptation to animal longevity  

PubMed Central

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

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

2013-01-01

38

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

NASA Astrophysics Data System (ADS)

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.

Kohn, Matthew J.

1996-12-01

39

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

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

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

40

The adaptation of digestive enzymes to the diet : Its physiological significance  

E-print Network

The adaptation of digestive enzymes to the diet : Its physiological significance T. CORRING adapt to the diet when substrate intake is altered. An analysis of experimental works shows breakdown of dietary components. In the first part of this paper,I have pooled the data on the adaptive

Paris-Sud XI, Université de

41

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

ERIC Educational Resources Information Center

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)

Fleck, Stephen J.; Kraerner, William J.

1988-01-01

42

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

PubMed Central

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.

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

2015-01-01

43

Physiology of environmental adaptations and resource acquisition in cockroaches.  

PubMed

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

Mullins, Donald E

2015-01-01

44

Human Adaptation to Space: Space Physiology and Countermeasures  

NASA Technical Reports Server (NTRS)

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;

Fogarty, Jennifer

2009-01-01

45

Physiological adaptations to thermal stress in tropical asians  

Microsoft Academic Search

Summary  Young sedentary adult males of Malay, Indian, and Chinese origin who had established continuous residence in tropical Malaysia and presumed to be naturally acclimatized to heat, were studied to evaluate their physiological responses to a standard heat stress test. The Malay and Indian races have evolved in hot and humid geographical zones, whereas the Chinese originated from a temperate area.

Margaret Tong Duncan; Steven M. Horvath

1988-01-01

46

Molecular aspects of oxygen sensing in physiological adaptation to hypoxia.  

PubMed

Oxygen is an essential substrate in aerobic metabolism for most eukaryotic organisms. Thus organisms and cells have developed numerous immediate and long-term compensatory mechanisms for dealing with oxygen deprivation. Adaptation to hypoxia at the organismal level includes reflex hyperventilation, polycythemia and angiogenesis, which lead to increased O2 delivery to the tissues. Adaptation at the cellular level involves a shift from oxidative phosphorylation to anaerobic glycolysis, increased glucose metabolism, and expression of hypoxic stress-related proteins. Regulation of many proteins participating in adaptation to hypoxia occurs at the level of gene expression. The most widespread molecular mechanism of hypoxia-dependent regulation is transcriptional induction via the binding of a transcription factor, hypoxia-inducible factor-1 (Hif-1), to the specific sequences on the regulated genes. Long-term induction of many proteins also requires an increase in mRNA stability, which is mediated by the binding of regulatory proteins to specific sequences within the mRNAs. The current theories of coupling between the O2 sensor and mechanisms controlling gene expression are discussed. PMID:9407604

Czyzyk-Krzeska, M F

1997-11-01

47

Effects of Dietary Sodium Bicarbonate and Calcium Chloride on Physiological Responses of Lactating Dairy Cows in Hot Weather  

Microsoft Academic Search

Twenty-four lactating cows were as- signed randomly to three treatments to evaluate responses to large differences of dietary sodium and chloride. Treatments were corn-cottonseed meal-corn silage based complete rations with either: 1) .23% sodium chloride (control), 2) control plus 2.28% calcium chloride, or 3) control plus 1.70% sodium bicarbonate.

A. Escobosa; C. E. Coppock; L. D. Rowe Jr; W. L. Jenkins; C. E. Gates

1984-01-01

48

Phenotyping for drought adaptation in wheat using physiological traits  

PubMed Central

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

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

2012-01-01

49

Turkeys and Cows  

NSDL National Science Digital Library

In honor of Thanksgiving, this blog posts an adaptation of the familiar chicken and cows problems that promote informal algebraic reasoning. Learners must find the correct number of turkeys and cows given the number of heads and the number of legs. A solution is modeled and a downloadable PDF of four more problems is included.

Terry Kawas

2011-11-17

50

Physiology  

ERIC Educational Resources Information Center

Discusses the scope of physiology and activities undertaken by physiologists. Indicates that a better understanding of the basic actions of cells and organs is the objective of physiological research. (CC)

Widdas, W. F.

1973-01-01

51

Allosteric Regulation of PKM2 Allows Cellular Adaptation to Different Physiological States  

NSDL National Science Digital Library

Pyruvate kinase isoform M2 (PKM2) activity is subject to complex allosteric regulation. Recently, serine and SAICAR (succinylaminoimidazolecarboxamide ribose-5?-phosphate) were identified as previously unrecognized activators of PKM2. These findings add additional complexity to how PKM2 is regulated in cells and support the notion that modulating PKM2 activity enables cells to adapt their metabolic state to specific physiological contexts.

Dan Y. Gui (Koch Institute for Integrative Cancer Research at Massachusetts Institute of Technology; REV)

2013-02-19

52

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

ERIC Educational Resources Information Center

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.…

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

53

Our ancestral physiological phenotype: An adaptation for hypoxia tolerance and for endurance performance?  

Microsoft Academic Search

There are well known mechanistic similari- ties in human physiology between adaptations for endurance performance and hypoxia tolerance. By using background principles arising from recent studies of the evolution of the diving response in marine mammals, here we analyze human responses to hypobaric hypoxia based on studies with several different low and high altitude human lineages. As in the evolution

PETER W. HOCHACHKA; HANNS CHRISTIAN GUNGA; KARL KIRSCH

1998-01-01

54

Physiological adaptations of Saccharomyces cerevisiae evolved for improved butanol tolerance  

PubMed Central

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

2013-01-01

55

Physiological and performance adaptations to high-intensity interval training.  

PubMed

High-intensity interval training (HIIT) refers to exercise that is characterized by relatively short bursts of vigorous activity, interspersed by periods of rest or low-intensity exercise for recovery. In untrained and recreationally active individuals, short-term HIIT is a potent stimulus to induce physiological remodeling similar to traditional endurance training despite a markedly lower total exercise volume and training time commitment. As little as six sessions of 'all-out' HIIT over 14 days, totaling ?15 min of intense cycle exercise within total training time commitment of ?2.5 h, is sufficient to enhance exercise capacity and improve skeletal muscle oxidative capacity. From an athletic standpoint, HIIT is also an effective strategy to improve performance when supplemented into the already high training volumes of well-trained endurance athletes, although the underlying mechanisms are likely different compared to less trained subjects. Most studies in this regard have examined the effect of replacing a portion (typically ?15-25%) of base/normal training with HIIT (usually 2-3 sessions per week for 4-8 weeks). It has been proposed that a polarized approach to training, in which ?75% of total training volume be performed at low intensities, with 10-15% performed at very high intensities may be the optimal training intensity distribution for elite athletes who compete in intense endurance events. PMID:23899754

Gibala, Martin J; Jones, Andrew M

2013-01-01

56

Physiological adaptation in noncompetitive rock climbers: good for aerobic fitness?  

PubMed

The present investigation aimed to establish whether noncompetitive rock climbing fulfills sports medicine recommendations for maintaining a good level of aerobic fitness. The physiological profile of 13 rock climbers, 8 men (age, 43 +/- 8 years) and 5 women (age, 31 +/- 8 years) was assessed by means of laboratory tests. Maximal aerobic power (VO2peak) and ventilatory threshold (VT) were assessed using a cycloergometer incremental test. During outdoor rock face climbing, VO2 and heart rate (HR) were measured with a portable metabolimeter and the relative steady-state values (VO2 and HR during rock climbing) were computed. Blood lactate was measured during recovery. All data are presented as mean +/- SD. VO2 was 39.1 +/- 4.3 mL.kg.min in men and 39.7 +/- 5 mL.kg.min in women, while VT was 29.4 +/- 3.0 mL.kg.min in men and 28.8 +/- 4.6 mL.kg.min in women. The VO2 during rock climbing was 28.3 +/- 1.5 mL.kg.min in men and 27.5 +/- 3.7 mL.kg.min in women. The HR during rock climbing was 144 +/- 16 b.min in men and 164 +/- 13 b.min in women. The aerobic profile was classified from excellent to superior in accordance with the standards of the American College of Sports Medicine (ACSM). The exercise intensity (VO2 during rock climbing expressed as a percentage of VO2peak) was 70 +/- 6% in men and 72 +/- 8% in women. Moreover, the energy expenditure was 1000-1500 kcal per week. In conclusion, noncompetitive rock climbing has proved to be a typical aerobic activity. The intensity of exercise is comparable to that recommended by the American College of Sports Medicine to maintain good cardiorespiratory fitness. PMID:18550948

Rodio, Angelo; Fattorini, Luigi; Rosponi, Alessandro; Quattrini, Filippo M; Marchetti, Marco

2008-03-01

57

Principles of exercise physiology: responses to acute exercise and long-term adaptations to training.  

PubMed

Physical activity and fitness are associated with a lower prevalence of chronic diseases, such as heart disease, cancer, high blood pressure, and diabetes. This review discusses the body's response to an acute bout of exercise and long-term physiological adaptations to exercise training with an emphasis on endurance exercise. An overview is provided of skeletal muscle actions, muscle fiber types, and the major metabolic pathways involved in energy production. The importance of adequate fluid intake during exercise sessions to prevent impairments induced by dehydration on endurance exercise, muscular power, and strength is discussed. Physiological adaptations that result from regular exercise training such as increases in cardiorespiratory capacity and strength are mentioned. The review emphasizes the cardiovascular and metabolic adaptations that lead to improvements in maximal oxygen capacity. PMID:23174541

Rivera-Brown, Anita M; Frontera, Walter R

2012-11-01

58

Physiology  

ERIC Educational Resources Information Center

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…

Kay, Ian

2008-01-01

59

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

PubMed Central

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

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

2012-01-01

60

Physiological and proteomic analysis of Lactobacillus casei in response to acid adaptation.  

PubMed

The aim of this study was to investigate the acid tolerance response (ATR) in Lactobacillus casei by a combined physiological and proteomic analysis. To optimize the ATR induction, cells were acid adapted for 1 h at different pHs, and then acid challenged at pH 3.5. The result showed that acid adaptation improved acid tolerance, and the highest survival was observed in cells adapted at pH 4.5 for 1 h. Analysis of the physiological data showed that the acid-adapted cells exhibited higher intracellular pH (pHi), intracellular NH4 (+) content, and lower inner permeability compared with the cells without adaptation. Proteomic analysis was performed upon acid adaptation to different pHs (pH 6.5 vs. pH 4.5) using two-dimensional electrophoresis. A total of 24 proteins that exhibited at least 1.5-fold differential expression were identified. Four proteins (Pgk, LacD, Hpr, and Galm) involved in carbohydrate catabolism and five classic stress response proteins (GroEL, GrpE, Dnak, Hspl, and LCAZH_2811) were up-regulated after acid adaptation at pH 4.5 for 1 h. Validation of the proteomic data was performed by quantitative RT-PCR, and transcriptional regulation of all selected genes showed a positive correlation with the proteomic patterns of the identified proteins. Results presented in this study may be useful for further elucidating the acid tolerance mechanisms and may help in formulating new strategies to improve the industrial performance of this species during acid stress. PMID:25062817

Wu, Chongde; He, Guiqiang; Zhang, Juan

2014-10-01

61

Sexually dimorphic adaptations in basal maternal stress physiology during pregnancy and implications for fetal development.  

PubMed

There is clear evidence of reciprocal exchange of information between the mother and fetus during pregnancy but the majority of research in this area has focussed on the fetus as a recipient of signals from the mother. Specifically, physiological signals produced by the maternal stress systems in response to the environment may carry valuable information about the state of the external world. Prenatal stress produces sex-specific adaptations within fetal physiology that have pervasive and long-lasting effects on development. Little is known, however, about the effects of sex-specific fetal signals on maternal adaptations to pregnancy. The current prospective study examined sexually dimorphic adaptations within maternal stress physiology, including the hypothalamic-adrenal-pituitary (HPA) axis and the autonomic nervous system (ANS) and associations with fetal growth. Using diurnal suites of saliva collected in early and late pregnancy, we demonstrate that basal cortisol and salivary alpha-amylase (sAA) differ by fetal sex. Women carrying female fetuses displayed greater autonomic arousal and flatter (but more elevated) diurnal cortisol patterns compared to women carrying males. Women with flatter daytime cortisol trajectories and more blunted sAA awakening responses also had infants with lower birth weight. These maternal adaptations are consistent with sexually dimorphic fetal developmental/evolutionary adaptation strategies that favor growth for males and conservation of resources for females. The findings provide new evidence to suggest that the fetus contributes to maternal HPA axis and ANS regulation during pregnancy and that these systems also contribute to the regulation of fetal growth. PMID:25827961

Giesbrecht, Gerald F; Campbell, Tavis; Letourneau, Nicole

2015-06-01

62

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

PubMed Central

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

Givnish, Thomas J.; Montgomery, Rebecca A.

2014-01-01

63

Generation of an index for physiological imbalance and its use as a predictor of primary disease in dairy cows during early lactation.  

PubMed

Physiological imbalance (PI) is a situation in which physiological parameters deviate from the normal and cows consequently have an increased risk of developing production diseases and reduced production or reproduction. The objectives of this work were (1) to generate an index for PI based on several plasma metabolites and (2) to compare the use of this index with calculated energy balance (EBAL) and individual plasma metabolites in relation to risk of disease during early lactation. We used a total of 634 lactations from 317 cows consisting of 3 breeds ranging from a parity of 1 to 4. Weekly blood samples were analyzed for selected metabolites; that is, urea nitrogen, albumin, cholesterol, nonesterified fatty acids (NEFA), glucose, and ?-hydroxybutyrate (BHBA). Energy intake and EBAL were calculated; veterinary treatment records and daily composite milk somatic cell counts were used to determine incidence of disease. Data were adjusted for numerous fixed effects (e.g., parity, breed, and week around calving) before further statistical analysis. The time of disease (TOD) was recorded as the day in which the signs of disease were observed (TOD=0). The week before and after TOD was ± n wk relative to TOD=0. Each week, all plasma metabolites were individually adjusted to an overall mean (=0) and variance (=1). The normalized variables were included in regression analyses by week of lactation to identify metabolites that explain the variation in calculated EBAL, as a reflection of degree of PI. Nonesterified fatty acids, BHBA, and glucose were weighted within each week based on regression coefficients (i.e., x1-x3 below) generated from a model to predict EBAL. Data from wk -1 relative to TOD were analyzed using a mixed linear model to relate degree of PI and metabolites in blood to risk of disease. The weekly PI index was defined as PI=(x1 × [NEFA])+x2 × [BHBA] - x3 × [glucose])/3. For diseases that developed ? 2 wk after calving, no variables were associated with risk of disease. Prepartal PI and plasma NEFA were better predictors of disease (i.e., metritis, retained placenta, and milk fever) at wk 1 than EBAL and plasma BHBA and glucose. Examining the relationship between PI and milk constituents is needed for the development of an automated in-line and real-time surveillance system for early detection of risk animals on-farm. PMID:23403197

Moyes, K M; Larsen, T; Ingvartsen, K L

2013-04-01

64

Adaptation to altitude as a vehicle for experiential learning of physiology by university undergraduates  

NSDL National Science Digital Library

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. Here, teams of three to four students measured the maximal rate of oxygen uptake, cognitive function, hand and foot volume changes, reticulocyte count and hematocrit, urinary pH and 24-h urine volume, athletic performance, and nocturnal blood oxygen saturation. Their data allowed the students to quantify the effect of altitude on the oxygen cascade and to demonstrate the following altitude-related changes: 1) impaired performance on selected cognitive function tests, 2) mild peripheral edema, 3) rapid reticulocytosis, 4) urinary alkalinization and diuresis, 5) impaired aerobic but not anaerobic exercise performance, 6) inverse relationship between blood oxygen saturation and resting heart rate, and 7) regular periodic nocturnal oxygen desaturation events accompanied by heart rate accelerations. The students learned and applied basic statistical techniques to analyze their data, and each team summarized its results in the format of a scientific paper. The students were uniformly enthusiastic about the use of self-directed experimentation to explore the physiology of altitude adaptation and felt that they learned more from this course format than a control group of students felt that they learned from a physiology course taught by the same instructor in the standard classroom/laboratory format.

David S Weigle (University of Washington Medicine)

2007-05-16

65

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

SciTech Connect

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.

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

66

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

PubMed Central

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

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

2009-01-01

67

Use of physiological constraints to identify quantitative design principles for gene expression in yeast adaptation to heat shock  

Microsoft Academic Search

Background: Understanding the relationship between gene expression changes, enzyme activity shifts, and the corresponding physiological adaptive response of organisms to environmental cues is crucial in explaining how cells cope with stress. For example, adaptation of yeast to heat shock involves a characteristic profile of changes to the expression levels of genes coding for enzymes of the glycolytic pathway and some

Ester Vilaprinyó; Rui Alves; Albert Sorribas

2006-01-01

68

Behavioural and physiological adaptations to low-temperature environments in the common frog, Rana temporaria  

PubMed Central

Background Extreme environments can impose strong ecological and evolutionary pressures at a local level. Ectotherms are particularly sensitive to low-temperature environments, which can result in a reduced activity period, slowed physiological processes and increased exposure to sub-zero temperatures. The aim of this study was to assess the behavioural and physiological responses that facilitate survival in low-temperature environments. In particular, we asked: 1) do high-altitude common frog (Rana temporaria) adults extend the time available for larval growth by breeding at lower temperatures than low-altitude individuals?; and 2) do tadpoles sampled from high-altitude sites differ physiologically from those from low-altitude sites, in terms of routine metabolic rate (RMR) and freeze tolerance? Breeding date was assessed as the first day of spawn observation and local temperature recorded for five, paired high- and low-altitude R. temporaria breeding sites in Scotland. Spawn was collected and tadpoles raised in a common laboratory environment, where RMR was measured as oxygen consumed using a closed respiratory tube system. Freeze tolerance was measured as survival following slow cooling to the point when all container water had frozen. Results We found that breeding did not occur below 5°C at any site and there was no significant relationship between breeding temperature and altitude, leading to a delay in spawning of five days for every 100 m increase in altitude. The relationship between altitude and RMR varied by mountain but was lower for individuals sampled from high- than low-altitude sites within the three mountains with the highest high-altitude sites (?900 m). In contrast, individuals sampled from low-altitudes survived freezing significantly better than those from high-altitudes, across all mountains. Conclusions Our results suggest that adults at high-altitude do not show behavioural adaptations in terms of breeding at lower temperatures. However, tadpoles appear to have the potential to adapt physiologically to surviving at high-altitude via reduced RMR but without an increase in freeze tolerance. Therefore, survival at high-altitude may be facilitated by physiological mechanisms that permit faster growth rates, allowing completion of larval development within a shorter time period, alleviating the need for adaptations that extend the time available for larval growth. PMID:24885261

2014-01-01

69

SIRT1: Linking Adaptive Cellular Responses to aging-associated Changes in Organismal Physiology  

NSDL National Science Digital Library

Sirtuins comprise a family of enzymes implicated in the determination of organismal life span in yeast and the nematode. The mammalian sirtuin SIRT1 has been shown to deacetylate several proteins in an NAD+-dependent manner. SIRT1 substrates are involved in the regulation of apoptosis/cell survival, endocrine signaling, differentiation, chromatin remodeling, and transcription. Thus SIRT1 provides a molecular link between nutrient availability and adaptive transcriptional responses. This review presents current evidence as to how SIRT1 functions are relevant to changes in tissue physiology that occur with ageing and its implications for future pharmacological intervention to alleviate such degenerative processes.

2006-12-01

70

A study of physiological responses of lactating dairy cows to summer climatic factors under shaded and non-shaded conditions  

E-print Network

'-=sec dies. Bee i 88 "l B. , : Bep-'. 8 lol; vs, e espe ses 17. Analysi. s o" variance of day totals o. respiration rate responses within the Holstsins 18. A, . alrsls of' variance of' day -otals of respiration rate rsspo"ses wl. , ii. n tbe Jerseys... milk wsi. ght, to expected milk weight within. the Jerseys 48 22. Simple coe "f'lclents of co:relation between e. vlronmental variables and physiological responses under different concit lens 23. Simple coefficients oi' cox. elation among...

Harris, Dewey Lynn

1958-01-01

71

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

PubMed Central

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

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

2013-01-01

72

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

PubMed Central

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

2011-01-01

73

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

PubMed

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

Oxenham, Marc F; Matsumura, Hirofumi

2008-01-01

74

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

PubMed

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

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

2005-04-01

75

Adaptation to Shift Work: Physiologically Based Modeling of the Effects of Lighting and Shifts’ Start Time  

PubMed Central

Shift work has become an integral part of our life with almost 20% of the population being involved in different shift schedules in developed countries. However, the atypical work times, especially the night shifts, are associated with reduced quality and quantity of sleep that leads to increase of sleepiness often culminating in accidents. It has been demonstrated that shift workers’ sleepiness can be improved by a proper scheduling of light exposure and optimizing shifts timing. Here, an integrated physiologically-based model of sleep-wake cycles is used to predict adaptation to shift work in different light conditions and for different shift start times for a schedule of four consecutive days of work. The integrated model combines a model of the ascending arousal system in the brain that controls the sleep-wake switch and a human circadian pacemaker model. To validate the application of the integrated model and demonstrate its utility, its dynamics are adjusted to achieve a fit to published experimental results showing adaptation of night shift workers (n?=?8) in conditions of either bright or regular lighting. Further, the model is used to predict the shift workers’ adaptation to the same shift schedule, but for conditions not considered in the experiment. The model demonstrates that the intensity of shift light can be reduced fourfold from that used in the experiment and still produce good adaptation to night work. The model predicts that sleepiness of the workers during night shifts on a protocol with either bright or regular lighting can be significantly improved by starting the shift earlier in the night, e.g.; at 21?00 instead of 00?00. Finally, the study predicts that people of the same chronotype, i.e. with identical sleep times in normal conditions, can have drastically different responses to shift work depending on their intrinsic circadian and homeostatic parameters. PMID:23308206

Postnova, Svetlana; Robinson, Peter A.; Postnov, Dmitry D.

2013-01-01

76

Behavioural and physiological effect of dental environment sensory adaptation on children's dental anxiety.  

PubMed

Dental anxiety is a serious obstacle in conventional oral healthcare delivery. A sensory adapted dental environment (SDE) might be effective in reducing anxiety and inducing relaxation. This study aimed to assess the efficacy of a Snoezelen SDE in reducing anxiety among children undergoing scaling and polishing by a dental hygienist. The Snoezelen environment consists of a partially dimmed room with lighting effects, vibroacoustic stimuli, and deep pressure. Nineteen children, aged 6-11 yr, participated in a cross-over intervention trial. Behavioral parameters included the mean number, duration, and magnitude of anxious behaviors, as monitored by videotaped recordings. Physiological parameters reflecting arousal were monitored by changes in dermal resistance. Results, by all measures, consistently indicated that both behavioral and psychophysiological measures of relaxation improved significantly in the SDE compared with a conventional dental environment. The findings support recommending the SDE as an effective and practical alternative in oral healthcare delivery to anxious children. PMID:18028056

Shapiro, Michele; Melmed, Raphael N; Sgan-Cohen, Harold D; Eli, Ilana; Parush, Shula

2007-12-01

77

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

PubMed

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

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

2004-09-01

78

Invited review: heat stress effects during late gestation on dry cows and their calves.  

PubMed

In dairy cattle, late gestation is a critical period for fetal growth and physiological transition into the next lactation. Environmental factors, such as temperature and light, exert dramatic effects on the production, health, and well-being of animals during this period and after parturition. The aim of this review was to introduce effects of heat stress during late gestation on dairy cattle, and discuss the biological mechanisms that underlie the observed production and health responses in the dam and her fetus. Relative to cooled cows, cows that are heat stressed during late gestation have impaired mammary growth before parturition and decreased milk production in the subsequent lactation. In response to higher milk yield, cows cooled prepartum undergo a series of homeorhetic adaptations in early lactation to meet higher demand for milk synthesis compared with heat-stressed cows, but no direct effect of environmental heat stress on metabolism exists during the dry period. Prepartum cooling improves immune status of transition cows and evidence suggests that altered prolactin signaling in immune cells mediates the effects of heat stress on immune function. Late-gestation heat stress compromises placental development, which results in fetal hypoxia, malnutrition, and eventually fetal growth retardation. Maternal heat stress may also have carryover effects on the postnatal growth of offspring, but direct evidence is still lacking. Emerging evidence suggests that offspring from prepartum heat-stressed cows have compromised passive immunity and impaired cell-mediated immune function compared with those from cooled cows. PMID:23664343

Tao, S; Dahl, G E

2013-07-01

79

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.  

PubMed

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?cows recorded the highest tick loads under the tails of all the cows used in the study from the three farms (P?cows with long hairs. Hair lengths were longest during the winter season in the coastal areas of Zazulwana and Honeydale (P?cows had significantly longer (P?cows. PMID:25172085

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

2014-08-30

80

The Effects of Restraint Using Self-Locking Stanchions on Dairy Cows in Relation to Behavior, Feed Intake, Physiological Parameters, Health, and Milk Yield1,2  

Microsoft Academic Search

Holstein cows (n = 64) ranging from peak to end lactation were restrained in self-locking stanchions (i.e., head locks) for approximately 4 h\\/d for four periods in a modified switchback design. Milk yield, milk fat percentage, somatic cell count, and dry mat- ter intake and dry matter intake were unaffected by restraint. Milk protein percentage was significantly lower for cows

D. J. BOLINGER; J. L. ALBRIGHT; J. MORROW-TESCH; S. J. KENYON; M. D. CUNNINGHAM

81

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)

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.

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

1990-09-01

82

Assessment of heifer grazing experience on short-term adaptation to pasture and performance as lactating cows  

Technology Transfer Automated Retrieval System (TEKTRAN)

A 3-yr study evaluated the carryover effects of dairy heifer grazing experience on behavior and first lactation performance as dairy cows. Forty-one Holstein and 23 Holstein-Jersey crossbred calves born between January and April 2008 were randomly assigned to one of four treatments (PP, PC, CP and C...

83

Membrane Composition Changes and Physiological Adaptation by Streptococcus mutans Signal Recognition Particle Pathway Mutants?  

PubMed Central

Previously, we presented evidence that the oral cariogenic species Streptococcus mutans remains viable but physiologically impaired and sensitive to environmental stress when genes encoding the minimal conserved bacterial signal recognition particle (SRP) elements are inactivated. Two-dimensional gel electrophoresis of isolated membrane fractions from strain UA159 and three mutants (?ffh, ?scRNA, and ?ftsY) grown at pH 7.0 or pH 5.0 allowed us to obtain insight into the adaptation process and the identities of potential SRP substrates. Mutant membrane preparations contained increased amounts of the chaperones DnaK and GroES and ClpP protease but decreased amounts of transcription- and translation-related proteins, the ? subunit of ATPase, HPr, and several metabolic and glycolytic enzymes. Therefore, the acid sensitivity of SRP mutants might be caused in part by diminished ATPase activity, as well as the absence of an efficient mechanism for supplying ATP quickly at the site of proton elimination. Decreased amounts of LuxS were also observed in all mutant membranes. To further define physiological changes that occur upon disruption of the SRP pathway, we studied global gene expression in S. mutans UA159 (parent strain) and AH333 (?ffh mutant) using microarray analysis. Transcriptome analysis revealed up-regulation of 81 genes, including genes encoding chaperones, proteases, cell envelope biosynthetic enzymes, and DNA repair and replication enzymes, and down-regulation of 35 genes, including genes concerned with competence, ribosomal proteins, and enzymes involved in amino acid and protein biosynthesis. Quantitative real-time reverse transcription-PCR analysis of eight selected genes confirmed the microarray data. Consistent with a demonstrated defect in competence and the suggested impairment of LuxS-dependent quorum sensing, biofilm formation was significantly decreased in each SRP mutant. PMID:17085548

Hasona, Adnan; Zuobi-Hasona, Kheir; Crowley, Paula J.; Abranches, Jacqueline; Ruelf, Michael A.; Bleiweis, Arnold S.; Brady, L. Jeannine

2007-01-01

84

Physiological cellular responses and adaptations of Rhodococcus erythropolis IBBPo1 to toxic organic solvents.  

PubMed

A new Gram-positive bacterium, Rhodococcus erythropolis IBBPo1 (KF059972.1) was isolated from a crude oil-contaminated soil sample by enrichment culture method. R. erythropolis IBBPo1 was able to tolerate a wide range of toxic compounds, such as antibiotics (800-1000?g/mL), synthetic surfactants (50-200?g/mL), and organic solvents (40%-100%). R. erythropolis IBBPo1 showed good tolerance to both alkanes (cyclohexane, n-hexane, n-decane) and aromatics (toluene, styrene, ethylbenzene) with logPOW (logarithm of the partition coefficient of the solvent in octanol-water mixture) values between 2.64 and 5.98. However, alkanes were less toxic for R. erythropolis IBBPo1 cells, compared with aromatics. The high organic solvent tolerance of R. erythropolis IBBPo1 could be due to the presence in their large genome of some catabolic (alkB, alkB1, todC1, todM, xylM), transporter (HAE1) and trehalose-6-phosphate synthase (otsA1, KF059973.1) genes. Numerous and complex physiological cellular responses and adaptations involved in organic solvent tolerance were revealed in R. erythropolis IBBPo1 cells exposed 1 and 24hr to 1% organic solvents. R. erythropolis IBBPo1 cells adapt to 1% organic solvents by changing surface hydrophobicity, morphology and their metabolic fingerprinting. Considerable modifications in otsA1 gene sequence were also observed in cells exposed to organic solvents (except ethylbenzene). PMID:25288551

Stancu, Mihaela Marilena

2014-10-01

85

Phytoplankton production and physiological adaptation on the southeastern shelf of the Agulhas ecosystem  

NASA Astrophysics Data System (ADS)

An investigation of phytoplankton production and physiology was undertaken during two research cruises on the southeastern shelf of southern Africa. The data set included photosynthesis-irradiance and active fluorescence parameters, phytoplankton absorption coefficients and HPLC pigment concentrations. Primary production was estimated to vary over a similar range for both cruises within 0.27-3.69 g C m -2 d -1. Pigment indices indicated that diatoms were dominant on the first cruise and the communities were subject to conditions where the mixed layer was deeper than the euphotic zone and they optimized their photosynthesis to very low light intensities at the bottom and below the euphotic zone. Mixed diatom-flagellate populations were observed during the second cruise where the euphotic zone was deeper than the mixed layer and the populations adapted to irradiances higher in the euphotic zone. In response to a mean lower water column PAR, it was found that these mixed communities increased the proportion of chlorophyll a in the pigment pool and had a higher quantum yield of photochemistry and higher light-limited photosynthetic efficiency.

Barlow, R.; Lamont, T.; Kyewalyanga, M.; Sessions, H.; Morris, T.

2010-07-01

86

Physiological adaptations to fasting in an actively wintering canid, the Arctic blue fox (Alopex lagopus).  

PubMed

This study investigated the physiological adaptations to fasting using the farmed blue fox (Alopex lagopus) as a model for the endangered wild arctic fox. Sixteen blue foxes were fed throughout the winter and 32 blue foxes were fasted for 22 d in Nov-Dec 2002. Half of the fasted blue foxes were food-deprived again for 22 d in Jan-Feb 2003. The farmed blue fox lost weight at a slower rate (0.97-1.02% body mass d(-1)) than observed previously in the arctic fox, possibly due to its higher initial body fat content. The animals experienced occasional fasting-induced hypoglycaemia, but their locomotor activity was not affected. The plasma triacylglycerol and glycerol concentrations were elevated during phase II of fasting indicating stimulated lipolysis, probably induced by the high growth hormone concentrations. The total cholesterol, HDL- and LDL-cholesterol, urea, uric acid and total protein levels and the urea:creatinine ratio decreased during fasting. Although the plasma levels of some essential amino acids increased, the blue foxes did not enter phase III of starvation characterized by stimulated proteolysis during either of the 22-d fasting procedures. Instead of excessive protein catabolism, it is liver dysfunction, indicated by the increased plasma bilirubin levels and alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase activities, that may limit the duration of fasting in the species. PMID:16358268

Mustonen, Anne-Mari; Pyykönen, Teija; Puukka, Matti; Asikainen, Juha; Hänninen, Sari; Mononen, Jaakko; Nieminen, Petteri

2006-01-01

87

Compensation of the Metabolic Costs of Antibiotic Resistance by Physiological Adaptation in Escherichia coli  

PubMed Central

Antibiotic resistance is often associated with metabolic costs. To investigate the metabolic consequences of antibiotic resistance, the genomic and transcriptomic profiles of an amoxicillin-resistant Escherichia coli strain and the wild type it was derived from were compared. A total of 125 amino acid substitutions and 7 mutations that were located <1,000 bp upstream of differentially expressed genes were found in resistant cells. However, broad induction and suppression of genes were observed when comparing the expression profiles of resistant and wild-type cells. Expression of genes involved in cell wall maintenance, DNA metabolic processes, cellular stress response, and respiration was most affected in resistant cells regardless of the absence or presence of amoxicillin. The SOS response was downregulated in resistant cells. The physiological effect of the acquisition of amoxicillin resistance in cells grown in chemostat cultures consisted of an initial increase in glucose consumption that was followed by an adaptation process. Furthermore, no difference in maintenance energy was observed between resistant and sensitive cells. In accordance with the transcriptomic profile, exposure of resistant cells to amoxicillin resulted in reduced salt and pH tolerance. Taken together, the results demonstrate that the acquisition of antibiotic resistance in E. coli is accompanied by specifically reorganized metabolic networks in order to circumvent metabolic costs. The overall effect of the acquisition of resistance consists not so much of an extra energy requirement, but more a reduced ecological range. PMID:23716056

Händel, Nadine; Schuurmans, J. Merijn; Brul, Stanley

2013-01-01

88

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

PubMed Central

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

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

2015-01-01

89

Physiological Adaptation of Desulfitobacterium hafniense Strain TCE1 to Tetrachloroethene Respiration?†  

PubMed Central

Desulfitobacterium spp. are ubiquitous organisms with a broad metabolic versatility, and some isolates have the ability to use tetrachloroethene (PCE) as terminal electron acceptor. In order to identify proteins involved in this organohalide respiration process, a comparative proteomic analysis was performed. Soluble and membrane-associated proteins obtained from cells of Desulfitobacterium hafniense strain TCE1 that were growing on different combinations of the electron donors lactate and hydrogen and the electron acceptors PCE and fumarate were analyzed. Among proteins increasingly expressed in the presence of PCE compared to fumarate as electron acceptor, a total of 57 proteins were identified by mass spectrometry analysis, revealing proteins involved in stress response and associated regulation pathways, such as PspA, GroEL, and CodY, and also proteins potentially participating in carbon and energy metabolism, such as proteins of the Wood-Ljungdahl pathway and electron transfer flavoproteins. These proteomic results suggest that D. hafniense strain TCE1 adapts its physiology to face the relative unfavorable growth conditions during an apparent opportunistic organohalide respiration. PMID:21478312

Prat, Laure; Maillard, Julien; Grimaud, Régis; Holliger, Christof

2011-01-01

90

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

PubMed

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

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

2015-01-01

91

Questioning the Resistance/Aerobic Training Dichotomy: A commentary on physiological adaptations determined by effort rather than exercise modality  

PubMed Central

This paper discusses and challenges the current opinion that exercise adaptation is generally defined by modality; resistance exercise (RE), or aerobic exercise (AE). In presenting a strong body of recent research which demonstrably challenges these perceptions we suggest alternate hypotheses towards physiological adaptation which is hinged more upon the effort than the exercise modality. Practical implications of this interpretation of exercise adaptation might effect change in exercise adherence since existing barriers to exercise of time, costs, specialized equipment, etc. become nullified. In presenting the evidence herein we suggest that lay persons wishing to attain the health and fitness (including strength and muscle hypertrophy) benefits of exercise can choose from a wide range of potential exercise modalities so long as the effort is high. Future research should consider this hypothesis by directly comparing RE and AE for acute responses and chronic adaptations. PMID:25713674

Fisher, James; Steele, James

2014-01-01

92

The effects of level of dietary protein on the milk production and rumen physiology of dairy cows fed a diet based on a tropical grass hay  

Microsoft Academic Search

Four rumen-fistulated, multiparous Holstein- Friesian cows in early lactation were offered mixed diets based on rhodes grass hay ( Chloris gayana ) cv. Callide containing 13, 14, 15 or 16% crude protein (CP) on a dry matter basis, in a 4 × 4 latin square design. The estimated undegradable protein concentration in these diets was similar with rumen degradable protein

B. C. GRANZIN; G. M C L. DRYDEN

93

Hibernation physiology, freezing adaptation and extreme freeze tolerance in a northern population of the wood frog.  

PubMed

We investigated hibernation physiology and freeze tolerance in a population of the wood frog, Rana sylvatica, indigenous to Interior Alaska, USA, near the northernmost limit of the species' range. Winter acclimatization responses included a 233% increase in the hepatic glycogen depot that was subsidized by fat body and skeletal muscle catabolism, and a rise in plasma osmolality that reflected accrual of urea (to 106±10 ?mol ml(-1)) and an unidentified solute (to ~73 ?mol ml(-1)). In contrast, frogs from a cool-temperate population (southern Ohio, USA) amassed much less glycogen, had a lower uremia (28±5 ?mol ml(-1)) and apparently lacked the unidentified solute. Alaskan frogs survived freezing at temperatures as low as -16°C, some 10-13°C below those tolerated by southern conspecifics, and endured a 2-month bout of freezing at -4°C. The profound freeze tolerance is presumably due to their high levels of organic osmolytes and bound water, which limits ice formation. Adaptive responses to freezing (-2.5°C for 48 h) and subsequent thawing (4°C) included synthesis of the cryoprotectants urea and glucose, and dehydration of certain tissues. Alaskan frogs differed from Ohioan frogs in retaining a substantial reserve capacity for glucose synthesis, accumulating high levels of cryoprotectants in brain tissue, and remaining hyperglycemic long after thawing. The northern phenotype also incurred less stress during freezing/thawing, as indicated by limited cryohemolysis and lactate accumulation. Post-glacial colonization of high latitudes by R. sylvatica required a substantial increase in freeze tolerance that was at least partly achieved by enhancing their cryoprotectant system. PMID:23966588

Costanzo, Jon P; do Amaral, M Clara F; Rosendale, Andrew J; Lee, Richard E

2013-09-15

94

Conflicts of thermal adaptation and fever--a cybernetic approach based on physiological experiments.  

PubMed

Cold adaptation aims primarily at a better economy, i.e., preservation of energy often at the cost of a lower mean body temperature during cold stress, whereas heat adaptation whether achieved by exposure to a hot environment or by endogenous heat produced by muscle exercise, often brings about a higher efficiency of control, i.e., a lower mean body temperature during heat stress, at the cost of a higher water loss. While cold adaptation is beneficial in a cold environment, it may constitute a detrimental factor for exposure to a hot environment, mainly because of morphological adaptation. Heat adaptation may be maladaptive for cold exposure, mainly because of functional adaptation. Heat adaptation clearly is best suited to avoid higher body temperatures in fever, no matter which environmental conditions prevail. On the other hand, cold adaptation is detrimental for coping with fever in hot environment. Yet, in the cold, preceding cold adaptation may, because of reduced metabolic heat production, result in lower febrile increase of body temperature. Apparently controversial effects and results may be analyzed in the framework of a cybernetic approach to the main mechanisms of thermal adaptation and fever. Morphological adaptations alter the properties of the heat transfer characteristics of the body ("passive system"), whereas functional adaptation and fever concern the subsystems of control, namely sensors, integrative centers and effectors. In a closed control-loop the two types of adaptation have totally different consequences. It is shown that the experimental results are consistent with the predictions of such an approach. PMID:9778894

Werner, J; Beckmann, U

1998-01-01

95

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

ERIC Educational Resources Information Center

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…

Karatoreos, Ilia N.; McEwen, Bruce S.

2013-01-01

96

Relation between QT interval and heart rate. New design of physiologically adaptive cardiac pacemaker  

Microsoft Academic Search

The relation between QT interval and heart rate has been studied in a group of patients undergoing physiological exercise, in a group undergoing atrial pacing without exercise, and in a group with complete heart block undergoing exercise at a fixed ventricular rate controlled by cardiac pacing. The expected shortening in QT interval during physiological exercise is only in part the

A F Rickards; J Norman

1981-01-01

97

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

ERIC Educational Resources Information Center

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,…

Lindblom, Tim

2006-01-01

98

Responses of energy balance, physiology, and production for transition dairy cows fed with a low-energy prepartum diet during hot season.  

PubMed

Twenty multiparous Chinese Holstein dairy cows calving in hot summer (S group), were compared with 20 similar control cows calving in cool autumn (C group). Diets were the same for both groups; prepartum diets had relatively low energy density. Average temperature-humidity index was 76.5 and 53.0 in summer and autumn, respectively. S group cows had significantly higher rectal temperatures (39.6 vs. 39.0 °C) and respiration rates (79.0 vs. 31.3 breaths/min) than C group, and consumed less feed (prepartum 8.0 vs. 12.3 kg/day, postpartum 16.3 vs. 21.2 kg/day). Calculated energy balance (EB) was -7.98 vs. -5.15 Mcal/day for S group prepartum and postpartum, respectively. In contrast, EB was 1.36 vs. -2.03 Mcal/day for C group prepartum and postpartum, respectively. S group produced significantly less milk than C group by 15.4 % (5.2 kg/day) and 26.8 % (10.2 kg/d) for milk yield and energy-corrected milk, respectively. Percentages of milk fat (3.28 vs. 4.29 %), protein (3.08 vs. 3.33 %), and solids-not-fat (8.46 vs. 8.78 %) were significantly lower for S group. Milk urea nitrogen (19.54 vs. 13.31 mg/dL) was significantly higher in S group. Significantly lower feed efficiency was observed in S group (1.56 vs. 1.66). During the entire transition period, S group had significantly lower circulating glucose levels. S group had significantly higher levels of nonesterified fatty acids (NEFA) prepartum, but after 14 days in milk, NEFA was significantly lower. We conclude that increasing dietary energy density during transition period (especially prepartum) is necessary to minimize adverse effects of hot season. PMID:23584629

Su, Huawei; Wang, Yachun; Zhang, Qian; Wang, Fuwei; Cao, Zhijun; Rahman, Muhammad Aziz Ur; Cao, Binghai; Li, Shengli

2013-10-01

99

Cow Madness  

NSDL National Science Digital Library

Mad Cows: The Why Files, provided by the University of Wisconsin, provides brief information on Mad Cow disease in layperson's language with hypertext links. Although prion research has been going on for over 25 years, the scientific and medical communities have only recently acknowledged the existence of prions and there remains serious debate over their role in a variety of neurological diseases. The name "prion" is derived from "proteinaceous infectious particles," and was coined by Dr. Stanley Prusiner, who discovered the agents and who recently received the Nobel Prize for Medicine for his work. Prions are thought to be the first transmissible and heritable disease-causing agents that lack DNA and RNA. They are composed solely of protein and appear to be the cause of such diseases as kuru and Creutzfeldt-Jakob disease in humans, and bovine spongiform encephalopathies, mad cow disease, and scrapie in sheep and goats.

100

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

PubMed Central

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

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

2012-01-01

101

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

NASA Astrophysics Data System (ADS)

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.

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

2015-02-01

102

Cardiovascular and respiratory physiology of tuna: adaptations for support of exceptionally high metabolic rates  

Microsoft Academic Search

Both physical and physiological modifications to the oxygen transport system promote high metabolic performance of tuna. The large surface area of the gills and thin blood-water barrier means that O2 utilization is high (30–50%) even when ram ventilation approaches 101 min-1kg-1. The heart is extremely large and generates peak blood pressures in the range of 70–100 mmHg at frequencies of

Peter G. Bushnell; David R. Jones

1994-01-01

103

Physiological interactions in Azolla-Anabaena system adapting to the salt stress  

Microsoft Academic Search

The effect of the different levels of salinity on some important physiological parameters among six species of Azolla has been investigated. Salinity reduced the growth (dry weight) and nitrogenase activity in Azolla-Anabaena association while heterocyst frequency was sharply increased. Minimum sodium accumulation and electrolyte leakage (EL) was observed up to 20mMNaCl whereas nitrate was accumulated significantly. Beyond 20mMNaCl, fronds having

Satya Shila Singh; Ram Sanmukh Upadhyay; Arun Kumar Mishra

2008-01-01

104

Individual Differences in Behavioral, Physiological, and Genetic Sensitivities to Contexts: Implications for Development and Adaptation  

Microsoft Academic Search

Although exposure to adversity places children at high risk for developmental problems, there is considerable variation in the adaptation of children exposed to both low and high levels of adversity. In recent years, researchers have made significant progress in understanding how social environments shape children’s development. Studies indicate that not all children are equally susceptible to environmental effects. In this

W. Thomas Boyce

2009-01-01

105

Space Physiology within an Exercise Physiology Curriculum  

ERIC Educational Resources Information Center

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…

Carter, Jason R.; West, John B.

2013-01-01

106

Transcriptional and Functional Adaptations of Human Endothelial Cells to Physiological Chronic Low Oxygen1  

PubMed Central

ABSTRACT Endothelial cells chronically reside in low-O2 environments in vivo (2%–13% O2), which are believed to be critical for cell homeostasis. To elucidate the roles of this physiological chronic normoxia in human endothelial cells, we examined transcriptomes of human umbilical vein endothelial cells (HUVECs), proliferation and migration of HUVECs in response to fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor A (VEGFA), and underlying signaling mechanisms under physiological chronic normoxia. Immediately after isolation, HUVECs were cultured steadily under standard cell culture normoxia (SCN; 21% O2) or physiological chronic normoxia (PCN; 3% O2) up to 25 days. We found that PCN up-regulated 41 genes and down-regulated 21 genes, 90% of which differed from those previously reported from HUVECs cultured under SCN and exposed to acute low O2. Gene ontology analysis indicated that PCN-regulated genes were highly related to cell proliferation and migration, consistent with the results from benchtop assays that showed that PCN significantly enhanced FGF2- and VEGFA-stimulated cell proliferation and migration. Interestingly, preexposing the PCN cells to 21% O2 up to 5 days did not completely diminish PCN-enhanced cell proliferation and migration. These PCN-enhanced cell proliferations and migrations were mediated via augmented activation of MEK1/MEK2/ERK1/ERK2 and/or PI3K/AKT1. Importantly, these PCN-enhanced cellular responses were associated with an increase in activation of VEGFR2 but not FGFR1, without altering their expression. Thus, PCN programs endothelial cells to undergo dramatic changes in transcriptomes and sensitizes cellular proliferative and migratory responses to FGF2 and VEGFA. These PCN cells may offer a unique endothelial model, more closely mimicking the in vivo states. PMID:23536375

Jiang, Yi-Zhou; Wang, Kai; Li, Yan; Dai, Cai-Feng; Wang, Ping; Kendziorski, Christina; Chen, Dong-Bao; Zheng, Jing

2013-01-01

107

Adaptation of Endothelial Cells to Physiologically-Modeled, Variable Shear Stress  

PubMed Central

Endothelial cell (EC) function is mediated by variable hemodynamic shear stress patterns at the vascular wall, where complex shear stress profiles directly correlate with blood flow conditions that vary temporally based on metabolic demand. The interactions of these more complex and variable shear fields with EC have not been represented in hemodynamic flow models. We hypothesized that EC exposed to pulsatile shear stress that changes in magnitude and duration, modeled directly from real-time physiological variations in heart rate, would elicit phenotypic changes as relevant to their critical roles in thrombosis, hemostasis, and inflammation. Here we designed a physiological flow (PF) model based on short-term temporal changes in blood flow observed in vivo and compared it to static culture and steady flow (SF) at a fixed pulse frequency of 1.3 Hz. Results show significant changes in gene regulation as a function of temporally variable flow, indicating a reduced wound phenotype more representative of quiescence. EC cultured under PF exhibited significantly higher endothelial nitric oxide synthase (eNOS) activity (PF: 176.0±11.9 nmol/105 EC; SF: 115.0±12.5 nmol/105 EC, p?=?0.002) and lower TNF-a-induced HL-60 leukocyte adhesion (PF: 37±6 HL-60 cells/mm2; SF: 111±18 HL-60/mm2, p?=?0.003) than cells cultured under SF which is consistent with a more quiescent anti-inflammatory and anti-thrombotic phenotype. In vitro models have become increasingly adept at mimicking natural physiology and in doing so have clarified the importance of both chemical and physical cues that drive cell function. These data illustrate that the variability in metabolic demand and subsequent changes in perfusion resulting in constantly variable shear stress plays a key role in EC function that has not previously been described. PMID:23457646

Uzarski, Joseph S.; Scott, Edward W.; McFetridge, Peter S.

2013-01-01

108

Physiological elevation of endogenous hormones results in superior strength training adaptation  

Microsoft Academic Search

The purpose of this study was to determine the influence of transiently elevated endogenous hormone concentrations during\\u000a exercise on strength training adaptations. Nine subjects performed four unilateral strength training session per week on the\\u000a elbow flexors for 11 weeks. During two of the weekly sessions, leg exercises were performed to acutely increase the systemic\\u000a anabolic hormone concentration immediately before the exercises

Bent R. RønnestadHa; Håvard Nygaard; Truls Raastad

109

Influence of gender and endogenous sex steroids on catecholaminergic structures involved in physiological adaptation to hypoxia  

Microsoft Academic Search

Mechanisms underlying sex-related differences in adaptation to high altitude were investigated by assessing the turnover\\u000a of dopamine and noradrenaline in structures of the chemoafferent pathway, i.e. carotid body and brainstem noradrenergic cell\\u000a groups (A1, A5, A6, A2 to which chemosensory fibres project). The influence of gender was assessed in male and female rats reared at an altitude\\u000a of 3600 m,

J. M. Pequignot; H. Spielvogel; E. Caceres; A. Rodriguez; B. Semporé; R. Favier

1997-01-01

110

On the salty side of life: molecular, physiological and anatomical adaptation and acclimation of trees to extreme habitats.  

PubMed

Saline and sodic soils that cannot be used for agriculture occur worldwide. Cultivating stress-tolerant trees to obtain biomass from salinized areas has been suggested. Various tree species of economic importance for fruit, fibre and timber production exhibit high salinity tolerance. Little is known about the mechanisms enabling tree crops to cope with high salinity for extended periods. Here, the molecular, physiological and anatomical adjustments underlying salt tolerance in glycophytic and halophytic model tree species, such as Populus euphratica in terrestrial habitats, and mangrove species along coastlines are reviewed. Key mechanisms that have been identified as mediating salt tolerance are discussed at scales from the genetic to the morphological level, including leaf succulence and structural adjustments of wood anatomy. The genetic and transcriptomic bases for physiological salt acclimation are salt sensing and signalling networks that activate target genes; the target genes keep reactive oxygen species under control, maintain the ion balance and restore water status. Evolutionary adaptation includes gene duplication in these pathways. Strategies for and limitations to tree improvement, particularly transgenic approaches for increasing salt tolerance by transforming trees with single and multiple candidate genes, are discussed. PMID:25159181

Polle, Andrea; Chen, Shaoliang

2014-08-27

111

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

PubMed Central

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

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

2005-01-01

112

Physiological fitness and health adaptations from purposeful training using off-road vehicles  

Microsoft Academic Search

The purpose of this study was to evaluate fitness and health adaptations from a training program riding all-terrain vehicles\\u000a (ATV) and off-road motorcycles (ORM) as the exercise stimulus. Participants (n = 58) were randomized to a control group (n = 12) or one of four experimental groups; 2 days\\/week ATV (n = 11), 2 days\\/week ORM (n = 12), 4 days\\/week ATV (n = 11), or 4 days\\/week ORM (n = 12). Aerobic fitness, musculoskeletal fitness,

J. F. Burr; V. K. Jamnik; N. Gledhill

113

Induction of Osmoadaptive Mechanisms and Modulation of Cellular Physiology Help Bacillus licheniformis Strain SSA 61 Adapt to Salt Stress.  

PubMed

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

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

114

Physiological adaptation of the Asian corn borer Ostrinia furnacalis to chemical defenses of its host plant, maize.  

PubMed

A number of gramineous plants such as maize contain cyclic hydroxamic acids (cHx) that are toxic to many herbivores. Among the Ostrinia species found in Japan, the Asian corn borer Ostrinia furnacalis is the only one that utilizes maize, a gramineous plant. We used O. furnacalis and two congeners, Ostrinia scapulalis and Ostrinia latipennis, to obtain insights into the physiological adaptation of O. furnacalis to cHx. When an artificial diet containing a low concentration (0.3mg/g diet) of cHx was fed to the larvae of O. furnacalis and O. scapulalis, larval growth and survival were significantly less affected in O. furnacalis than O. scapulalis. An artificial diet containing a high level (0.7mg/g diet) of cHx was found to severely retard the growth of both species, albeit to different degrees. In an assay in vitro, homogenate of the digestive tract of O. furnacalis larvae degraded cHx more rapidly than that of O. scapulalis or O. latipennis. The degradation was found to be enzymatic and dependent on a cofactor, UDP-glucose, suggesting that UDP-glucosyltransferase or other UDP-glucose-dependent enzymes were involved. This enzymatic adaptation probably has enabled O. furnacalis to utilize plants containing cHx. PMID:20435041

Kojima, Wataru; Fujii, Takeshi; Suwa, Momoko; Miyazawa, Mitsuo; Ishikawa, Yukio

2010-09-01

115

RNA sequencing of Populus x canadensis roots identifies key molecular mechanisms underlying physiological adaption to excess zinc.  

PubMed

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

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

2015-01-01

116

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

PubMed Central

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

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

2015-01-01

117

Behaviorally mediated, warm adaptation: a physiological strategy when mice behaviorally thermoregulate.  

PubMed

Laboratory mice housed under standard vivarium conditions with an ambient temperature (Ta) of ~22°C are likely to be cold stressed because this Ta is below their thermoneutral zone (TNZ). Mice raised at Tas within the TNZ adapt to the warmer temperatures, developing smaller internal organs and longer tails compared to mice raised at 22°C. Since mice prefer Tas equal to their TNZ when housed in a thermocline, we hypothesized that mice reared for long periods (e.g., months) in a thermocline would undergo significant changes in organ development and tail length as a result of their thermoregulatory behavior. Groups of three female BALB/c mice at an age of 37 days were housed together in a thermocline consisting of a 90cm long aluminum runway with a floor temperature ranging from 23 to 39°C. Two side-by-side thermoclines allowed for a total of 6 mice to be tested simultaneously. Control mice were tested in isothermal runways maintained at a Ta of 22°C. All groups were given cotton pads for bedding/nest building. Mass of heart, lung, liver, kidney, brain, and tail length were assessed after 73 days of treatment. Mice in the thermocline and control (isothermal) runways were compared to cage control mice housed 3/cage with bedding under standard vivarium conditions. Mice in the thermocline generally remained in the warm end throughout the daytime with little evidence of nest building, suggesting a state of thermal comfort. Mice in the isothermal runway built elaborate nests and huddled together in the daytime. Mice housed in the thermocline had significantly smaller livers and kidneys and an increase in tail length compared to mice in the isothermal runway as well as when compared to the cage controls. These patterns of organ growth and tail length of mice in the thermocline are akin to warm adaptation. Thus, thermoregulatory behavior altered organ development, a process we term behaviorally mediated, warm adaptation. Moreover, the data suggest that the standard vivarium conditions are likely a cold stress that alters normal organ development relative to mice allowed to select their thermal preferendum. PMID:25086972

Gordon, Christopher J; Aydin, Cenk; Repasky, Elizabeth A; Kokolus, Kathleen M; Dheyongera, Geoffrey; Johnstone, Andrew F M

2014-08-01

118

[Metabolic stability and physiological adaptation of muscle under conditions of exercise].  

PubMed

The first role played by group III (thin myelinated) and group IV (unmyelinated) afferent fibres from skeletal muscle is to transmit nociceptive information from muscle to the central nervous system. The second role of these free endings located in the interstitium of the muscle is to induce cardiovascular and respiratory adjustments during muscular exercise. These respiratory and circulatory responses during muscular exercise may be reflexly induced via muscular afferents. Indeed, static contraction of hindlimb muscles in anaesthetised mammals has been shown to reflexly increase the ventilatory function, the myocardial contractility and heart rate. The mechanical muscle deformation and the accumulation of metabolites in its intersitium are the cause of raised activity in small nerve fibres which in turn induces the physiological responses. It is also admitted that the central locomotor areas on the medullary and spinal neuronal pools control ventilatory and cardiovascular function during exercise. This mechanism is called "central command". Furthermore, adjustments of the locomotor activity during exercise is mediated by the thinly myelinated and unmyelinated fibres with endings in the working muscle. These fibres, also called "metaboreceptor" may be responsible of the coupling between the ventilation and the locomotion. Thickly myelinated muscle afferents (i.e. group I and II) appear to play little role in causing the reflex autonomic responses to contraction. PMID:15037842

Decherchi, P; Dousset, E; Grélot, L

2004-03-01

119

Cell adaptation to a physiologically relevant ECM mimic with different viscoelastic properties.  

PubMed

To successfully induce tissue repair or regeneration in vivo, bioengineered constructs must possess both optimal bioactivity and mechanical strength. This is because cell interaction with the extracellular matrix (ECM) produces two different but concurrent signaling mechanisms: ligation-induced signaling, which depends on ECM biological stimuli, and traction-induced signaling, which depends on ECM mechanical stimuli. In this report, we provide a fundamental understanding of how alterations in mechanical stimuli alone, produced by varying the viscoelastic properties of our bioengineered construct, modulate phenotypic behavior at the whole-cell level. Using a physiologically relevant ECM mimic composed of hyaluronan and fibronectin, we found that adult human dermal fibroblasts modify their mechanical response in order to match substrate stiffness. More specifically, the cells on stiffer substrates had higher modulus and a more stretched and organized actin cytoskeleton (and vice versa), which translated into larger traction forces exerted on the substrate. This modulation of cellular mechanics had contrasting effects on migration and proliferation, where cells migrated faster on softer substrates while proliferating preferentially on the stiffer ones. These findings implicate substrate rigidity as a critical design parameter in the development of bioengineered constructs aimed at eliciting maximal cell and tissue function. PMID:17049594

Ghosh, Kaustabh; Pan, Zhi; Guan, E; Ge, Shouren; Liu, Yajie; Nakamura, Toshio; Ren, Xiang-Dong; Rafailovich, Miriam; Clark, Richard A F

2007-02-01

120

Cell adaptation to a physiologically relevant ECM mimic with different viscoelastic properties  

PubMed Central

To successfully induce tissue repair or regeneration in vivo, bioengineered constructs must possess both optimal bioactivity and mechanical strength. This is because cell interaction with the extracellular matrix (ECM) produces two different but concurrent signaling mechanisms: ligation-induced signaling, which depends on ECM biological stimuli, and traction-induced signaling, which depends on ECM mechanical stimuli. In this report, we provide a fundamental understanding of how alterations in mechanical stimuli alone, produced by varying the viscoelastic properties of our bioengineered construct, modulate phenotypic behavior at the whole-cell level. Using a physiologically-relevant ECM mimic composed of hyaluronan and fibronectin, we found that adult human dermal fibroblasts modify their mechanical response in order to match substrate stiffness. More specifically, the cells on stiffer substrates had higher modulus and a more stretched and organized actin cytoskeleton (and vice versa), which translated into larger traction forces exerted on the substrate. This modulation of cellular mechanics had contrasting effects on migration and proliferation, where cells migrated faster on softer substrates while proliferating preferentially on the stiffer ones. These findings implicate substrate rigidity as a critical design parameter in the development of bioengineered constructs aimed at eliciting maximal cell and tissue function. PMID:17049594

Ghosh, Kaustabh; Pan, Zhi; Guan, E; Ge, Shouren; Liu, Yajie; Nakamura, Toshio; Ren, Xiang-Dong; Rafailovich, Miriam; Clark, Richard A.F.

2009-01-01

121

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

PubMed

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

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

122

Cellular, physiological, and molecular adaptive responses of Erwinia amylovora to starvation.  

PubMed

Erwinia amylovora causes fire blight, a destructive disease of rosaceous plants distributed worldwide. This bacterium is a nonobligate pathogen able to survive outside the host under starvation conditions, allowing its spread by various means such as rainwater. We studied E. amylovora responses to starvation using water microcosms to mimic natural oligotrophy. Initially, survivability under optimal (28 °C) and suboptimal (20 °C) growth temperatures was compared. Starvation induced a loss of culturability much more pronounced at 28 °C than at 20 °C. Natural water microcosms at 20 °C were then used to characterize cellular, physiological, and molecular starvation responses of E. amylovora. Challenged cells developed starvation-survival and viable but nonculturable responses, reduced their size, acquired rounded shapes and developed surface vesicles. Starved cells lost motility in a few days, but a fraction retained flagella. The expression of genes related to starvation, oxidative stress, motility, pathogenicity, and virulence was detected during the entire experimental period with different regulation patterns observed during the first 24 h. Further, starved cells remained as virulent as nonstressed cells. Overall, these results provide new knowledge on the biology of E. amylovora under conditions prevailing in nature, which could contribute to a better understanding of the life cycle of this pathogen. PMID:24476337

Santander, Ricardo D; Oliver, James D; Biosca, Elena G

2014-05-01

123

Physiological Adaptations and Countermeasures Associated with Long-Duration Space Flights  

NASA Technical Reports Server (NTRS)

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.

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

1994-01-01

124

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

PubMed

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

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

2015-02-01

125

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

PubMed

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

Brown, Alastair; Thatje, Sven

2014-05-01

126

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

PubMed Central

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

Brown, Alastair; Thatje, Sven

2014-01-01

127

Reproductive impacts and physiological adaptations of zebrafish to elevated dietary nickel.  

PubMed

Nickel (Ni) concentrations in the environment can rise due to human industrial activities. The toxicity of waterborne Ni to aquatic animals has been examined in a number of previous studies; however, little is known about the impacts of elevated dietary Ni. In the present study, zebrafish were chronically fed diets containing two concentrations of Ni [3.7 (control) and 116 ?g Ni/g diet]. Ni-exposed males, but not females, were significantly smaller (26%) compared to controls at 80 days. In addition, total egg production was decreased by 65% in the Ni treatment at 75-78 days of the experiment. Ni was ubiquitously distributed in control animals (similar to previous studies), and concentrations varied between tissues by 15-fold. Ni exposure resulted in modest but significant Ni accumulation in some tissues (increases were highest in brain, vertebrae and gut; 44%, 34% and 25%, respectively), an effect observed only at 80 days. The limited Ni accumulation may be due to (1) the lack of an acidified stomach in zebrafish and/or (2) the efficient upregulation of Ni transport and excretion mechanisms, as indicated by the 4.5-fold increase in waterborne (63)Ni uptake by Ni-exposed fish. Eggs from Ni-exposed adults had Ni concentrations that were 5.2-fold higher than controls. However, by 4 days post fertilization, larvae had similar Ni concentrations as controls, demonstrating a capacity for rapid Ni depuration. Larvae from Ni-exposed adults were also more resistant to waterborne Ni (35% increase in the 96-h LC50 over controls). In conclusion, elevated dietary Ni significantly affected zebrafish reproduction despite only modest tissue Ni accumulation. There were also indications of adaptation, including increased Ni uptake rates and increased Ni tolerance of offspring from Ni-exposed adults. Ni concentrations were particularly elevated in the brain with exposure; possible relations to growth and reproductive impacts require further study. PMID:24858402

Alsop, Derek; Lall, Santosh P; Wood, Chris M

2014-09-01

128

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

PubMed

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

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

2011-05-01

129

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)

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.

Holland, Albert W. (editor)

1987-01-01

130

Teaching the physiology of adaptation to hypoxic stress with the aid of a classic paper on high altitude by Houston and Riley  

NSDL National Science Digital Library

Many pathological conditions exist where tissues exhibit hypoxia or low oxygen tension. Hypoxic hypoxia arises when there is a reduction in the amount of oxygen entering the blood and occurs in healthy people at high altitude. In 1946, research sponsored by the United States Navy led to the collection and subsequent publication of masses of data demonstrating the physiological consequences and adaptations of ascent to high altitude. This article describes how a figure from a 1947 paper from the American Physiological Society Legacy collection (Houston CS, Riley RL. Respiratory and circulatory changes during acclimatization to high altitude. Am J Physiol 149: 565Â?588) may be used to allow students to review their understanding of some of the generalized effects of hypoxia on the body. In particular, this figure summarizes some of the adaptive responses that take place in the oxygen transport system as a consequence of prolonged hypoxia.

E M Tansey (Wellcome Institute for the History of Medicine)

2007-12-19

131

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 ...

132

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

NASA Astrophysics Data System (ADS)

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.

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

2009-10-01

133

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

PubMed

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

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

2014-10-01

134

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

PubMed

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

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

2013-07-01

135

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

PubMed Central

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

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

2013-01-01

136

Physiological screening for target site insensitivity and localization of Na(+)/K(+)-ATPase in cardenolide-adapted Lepidoptera.  

PubMed

Cardenolides are toxic plant compounds which specifically inhibit Na(+)/K(+)-ATPase, an animal enzyme which is essential for many physiological processes, such as the generation of action potentials. Several adapted insects feeding on cardenolide-containing plants sequester these toxins for their own defence. Some of these insects were shown to possess Na(+)/K(+)-ATPases with a reduced sensitivity towards cardenolides (target site insensitivity). In the present study we screened five species of arctiid moths feeding on cardenolide-containing plants for target site insensitivity towards cardenolides using an in vitro enzyme assay. The derived dose response curves of the respective Na(+)/K(+)-ATPases were compared to the insensitive Na(+)/K(+)-ATPase of the monarch butterfly (Danaus plexippus). Na(+)/K(+)-ATPases of all arctiid species tested were highly sensitive to ouabain, a water-soluble cardenolide which is most widely used in laboratory studies. Nevertheless, we detected substantial amounts of cardenolides in the haemolymph of two of the arctiid species. In caterpillars of the sequestering arctiid Empyreuma pugione and of D. plexippus we localized Na(+)/K(+)-ATPase by immunohistochemistry and western blot (in D. plexippus). Both techniques revealed strong expression of the enzyme in the nervous tissue and indicated weak expression or even absence in other tissues tested. We conclude that instead of target site insensitivity the investigated arctiid species use a different strategy to tolerate cardenolides. Most plausibly, the perineurium surrounding the nervous tissue functions as a barrier which prevents cardenolides from reaching Na(+)/K(+)-ATPase in the ventral nerve cord. PMID:22343317

Petschenka, Georg; Offe, Julia K; Dobler, Susanne

2012-05-01

137

Physiological evidence for the presence of a cis-trans isomerase of unsaturated fatty acids in Methylococcus capsulatus Bath to adapt to the presence of toxic organic compounds.  

PubMed

The physiology of the response in the methanotrophic bacterium Methylococcus capsulatus Bath towards thermal and solvent stress was studied. A systematic investigation of the toxic effects of organic compounds (chlorinated phenols and alkanols) on the growth of this bacterium was carried out. The sensitivity to the tested alkanols correlated with their chain length and hydrophobicity; methanol was shown to be an exception to which the cells showed a very high tolerance. This can be explained by the adaptation of these bacteria to growth on C1 compounds. On the other hand, M. capsulatus Bath was very sensitive towards the tested chlorinated phenols. The high toxic effect of phenolic compounds on methanotrophic bacteria might be explained by the occurrence of toxic reactive oxygen species. In addition, a physiological proof of the presence of cis-trans isomerization as a membrane-adaptive response mechanism in M. capsulatus was provided. This is the first report on physiological evidence for the presence of the unique postsynthetic membrane-adaptive response mechanism of the cis-trans isomerization of unsaturated fatty acids in a bacterium that does not belong to the genera Pseudomonas and Vibrio where this mechanism was already reported and described extensively. PMID:20487020

Löffler, Claudia; Eberlein, Christian; Mäusezahl, Ines; Kappelmeyer, Uwe; Heipieper, Hermann J

2010-07-01

138

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 ... Do? You might have heard news reports about mad cow disease and wondered: What the heck is ...

139

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

E-print Network

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 ...

Gibbons, Jennifer M.

140

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

NASA Astrophysics Data System (ADS)

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.

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

2009-05-01

141

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

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.…

Bugental, Daphne Blunt

2012-01-01

142

Factors affecting embryo donor performance in Brahman cows  

E-print Network

FACTORS AFFECTING EMBRYO DONOR PERFORMANCE IN BRAHMAN COWS A Thesis by PEDRO SEGUNDO BASTIDAS Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1986... Major Subject: Physiology of Reproduction FACTORS AFFECTING EMBRYO DONOR PERFORMANCE IN BRAHMAN COWS A Thesis by PEDRO SEGUNDO BASTIDAS Approved as to style and content by: R. D. Randel (Chairman of Committee) P. G. Harms (Committee Member) D...

Bastidas, Pedro Segundo

1986-01-01

143

Performance and Nutrient Intake of High Producing Holstein Cows Consuming Pasture or a Total Mixed Ration1  

Microsoft Academic Search

We compared the intakes of nutrients by high producing Holstein cows consuming pasture or a full nutrient positive control ration (total mixed ration; TMR) and identified nutrients that limited the milk production of cows consuming the high quality pasture. Cows (n = 8 ) were adapted to an all pasture diet by incrementally reducing the amount of TMR fed over

E. S. Kolver; L. D. Muller

1998-01-01

144

Dissecting the COW  

SciTech Connect

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.

Linstadt, E.

1985-04-01

145

Alkanols and chlorophenols cause different physiological adaptive responses on the level of cell surface properties and membrane vesicle formation in Pseudomonas putida DOT-T1E.  

PubMed

In order to cope with the toxicity imposed by the exposure to environmental hydrocarbons, many bacteria have developed specific adaptive responses such as modifications in the cell envelope. Here we compared the influence of n-alkanols and chlorophenols on the surface properties of the solvent-tolerant bacterium Pseudomonas putida DOT-T1E. In the presence of toxic concentrations of n-alkanols, this strain significantly increased its cell surface charge and hydrophobicity with changes depending on the chain length of the added n-alkanols. The adaptive response occurred within 10 min after the addition of the solvent and was demonstrated to be of physiological nature. Contrary to that, chlorophenols of similar hydrophobicity and potential toxicity as the corresponding alkanols caused only minor effects in the surface properties. To our knowledge, this is the first observation of differences in the cellular adaptive response of bacteria to compound classes of quasi equal hydrophobicity and toxicity. The observed adaptation of the physico-chemical surface properties of strain DOT-T1E to the presence of alkanols was reversible and correlated with changes in the composition of the lipopolysaccharide content of the cells. The reaction is explained by previously described reactions allowing the release of membrane vesicles that was demonstrated for cells affected by 1-octanol and heat shock, whereas no membrane vesicles were released after the addition of chlorophenols. PMID:21732242

Baumgarten, Thomas; Vazquez, José; Bastisch, Christian; Veron, Wilfried; Feuilloley, Marc G J; Nietzsche, Sandor; Wick, Lukas Y; Heipieper, Hermann J

2012-01-01

146

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

NASA Technical Reports Server (NTRS)

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.

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

147

Teaching Skeletal Muscle Adaptations to Aerobic Exercise Using an American Physiological Society Classic Paper by Dr. Philip Gollnick and Colleagues  

NSDL National Science Digital Library

Discussion of a strategy for using a classic paper to enhance the studentsÂ? ability to understand research, increase their knowledge of the adaptations to exercise, and learn computer skills in data analysis and presentation

PhD Gregory A. Brown (University of Nebraska, Kearney Department of Health, Physical Education, Recreation, and Leisure Studies)

2006-09-01

148

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

ERIC Educational Resources Information Center

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…

Nelson, Regina K.

2013-01-01

149

Cows and Sheep  

NSDL National Science Digital Library

Solvers of this problem apply number sense and logical reasoning to determine the numbers of cows and sheep in each of five fields by using clues about how many cows and sheep can be seen by each animal. The problem includes questions for getting started, suggestions for implementation and differentiation, a printable student page, and sample solutions.

2014-01-01

150

Fitting Cows to Your Operation  

Technology Transfer Automated Retrieval System (TEKTRAN)

Genetic diversity in cattle can be used to improve efficiency of the cow herd. A cow that is optimum in one production system may not be the best cow for another production system. To improve cow efficiency, we need to optimize the ratio of output to inputs. The optimum ratio on biological bases ...

151

Negative energy balance and hepatic gene expression patterns in high-yielding dairy cows during the early postpartum period: a global approach  

PubMed Central

In high-yielding dairy cows the liver undergoes extensive physiological and biochemical changes during the early postpartum period in an effort to re-establish metabolic homeostasis and to counteract the adverse effects of negative energy balance (NEB). These adaptations are likely to be mediated by significant alterations in hepatic gene expression. To gain new insights into these events an energy balance model was created using differential feeding and milking regimes to produce two groups of cows with either a mild (MNEB) or severe NEB (SNEB) status. Cows were slaughtered and liver tissues collected on days 6–7 of the first follicular wave postpartum. Using an Affymetrix 23k oligonucleotide bovine array to determine global gene expression in hepatic tissue of these cows, we found a total of 416 genes (189 up- and 227 downregulated) to be altered by SNEB. Network analysis using Ingenuity Pathway Analysis revealed that SNEB was associated with widespread changes in gene expression classified into 36 gene networks including those associated with lipid metabolism, connective tissue development and function, cell signaling, cell cycle, and metabolic diseases, the three most significant of which are discussed in detail. SNEB cows displayed reduced expression of transcription activators and signal transducers that regulate the expression of genes and gene networks associated with cell signaling and tissue repair. These alterations are linked with increased expression of abnormal cell cycle and cellular proliferation associated pathways. This study provides new information and insights on the effect of SNEB on gene expression in high-yielding Holstein Friesian dairy cows in the early postpartum period. PMID:20716645

McCarthy, S. D.; Waters, S. M.; Kenny, D. A.; Diskin, M. G.; Fitzpatrick, R.; Patton, J.; Wathes, D. C.

2010-01-01

152

Heat stress abatement for dry cows: Does cooling improve transition into lactation?  

Technology Transfer Automated Retrieval System (TEKTRAN)

Environmental factors, especially temperature and photoperiod, influence health and productivity of dairy cows during lactation, possibly via similar physiological effects. For example, heat stress is a critical component of lowered milk yield during summer. Long days improve yield during lactation...

153

Photosynthetic adaptation to temperature in four species from the Colorado shortgrass steppe: a physiological model for coexistence  

Microsoft Academic Search

Several aspects of photosynthetic adaptation to temperature were examined in four graminoid species from the Colorado shortgrass steppe. The experimental species were chosen to provide examples of a variety of in situ seasonal phenology patterns. The cool season grass, Agropyron smithii (C3), exhibited higher photosynthesis rates when grown in a cool temperature regime (20\\/15°C), and compared to warm grown plants

Russell K. Monson; Robert O. Littlejohn; George J. Williams

1983-01-01

154

Physiological, affective, and behavioral responses to interpersonal conflict among males from families with different levels of cohesion and adaptability  

Microsoft Academic Search

To examine the relation between characteristics of a person's family of origin and cardiovascular, behavioral, cognitive, and affective response to interpersonal conflict, responses of 15 young males from families rated as extreme (EXT) on scales of cohesion (enmeshed or disengaged) or adaptability (chaotic or rigid) were compared to those of 25 young males from families rated as balanced (BAL) on

Kevin T. Larkin; Nicole L. Frazer; Elizabeth M. Semenchuk

1996-01-01

155

Ruminant Metabolic Systems Biology: Reconstruction and Integration of Transcriptome Dynamics Underlying Functional Responses of Tissues to Nutrition and Physiological Statea  

PubMed Central

High-throughput ‘omics’ data analysis via bioinformatics is one key component of the systems biology approach. The systems approach is particularly well-suited for the study of the interactions between nutrition and physiological state with tissue metabolism and functions during key life stages of organisms such as the transition from pregnancy to lactation in mammals, ie, the peripartal period. In modern dairy cows with an unprecedented genetic potential for milk synthesis, the nature of the physiologic and metabolic adaptations during the peripartal period is multifaceted and involves key tissues such as liver, adipose, and mammary. In order to understand such adaptation, we have reviewed several works performed in our and other labs. In addition, we have used a novel bioinformatics approach, Dynamic Impact Approach (DIA), in combination with partly previously published data to help interpret longitudinal biological adaptations of bovine liver, adipose, and mammary tissue to lactation using transcriptomics datasets. Use of DIA with transcriptomic data from those tissues during normal physiological adaptations and in animals fed different levels of energy prepartum allowed visualization and integration of most-impacted metabolic pathways around the time of parturition. The DIA is a suitable tool for applying the integrative systems biology approach. The ultimate goal is to visualize the complexity of the systems at study and uncover key molecular players involved in the tissue’s adaptations to physiological state or nutrition. PMID:22807626

Bionaz, Massimo; Loor, Juan J.

2012-01-01

156

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

PubMed Central

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

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

2014-01-01

157

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

NASA Technical Reports Server (NTRS)

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.

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

2001-01-01

158

The western painted turtle genome, a model for the evolution of extreme physiological adaptations in a slowly evolving lineage  

PubMed Central

Background We describe the genome of the western painted turtle, Chrysemys picta bellii, one of the most widespread, abundant, and well-studied turtles. We place the genome into a comparative evolutionary context, and focus on genomic features associated with tooth loss, immune function, longevity, sex differentiation and determination, and the species' physiological capacities to withstand extreme anoxia and tissue freezing. Results Our phylogenetic analyses confirm that turtles are the sister group to living archosaurs, and demonstrate an extraordinarily slow rate of sequence evolution in the painted turtle. The ability of the painted turtle to withstand complete anoxia and partial freezing appears to be associated with common vertebrate gene networks, and we identify candidate genes for future functional analyses. Tooth loss shares a common pattern of pseudogenization and degradation of tooth-specific genes with birds, although the rate of accumulation of mutations is much slower in the painted turtle. Genes associated with sex differentiation generally reflect phylogeny rather than convergence in sex determination functionality. Among gene families that demonstrate exceptional expansions or show signatures of strong natural selection, immune function and musculoskeletal patterning genes are consistently over-represented. Conclusions Our comparative genomic analyses indicate that common vertebrate regulatory networks, some of which have analogs in human diseases, are often involved in the western painted turtle's extraordinary physiological capacities. As these regulatory pathways are analyzed at the functional level, the painted turtle may offer important insights into the management of a number of human health disorders. PMID:23537068

2013-01-01

159

Physiological adaptations in the lichens Peltigera rufescens and Cladina arbuscula var. mitis, and the moss Racomitrium lanuginosum to copper-rich substrate.  

PubMed

Two lichen species (Peltigera rufescens and Cladina arbuscula subsp. mitis) and one moss species (Racomitrium lanuginosum) growing on a copper mine heaps (probably 200-300yr old) in the village of Spania dolina (Slovak Republic) were assessed for selected physiological parameters, including composition of assimilation pigments, chlorophyll a fluorescence, soluble proteins and free amino acid content. The lichen C. arbuscula subsp. mitis was collected also at a control locality where total copper concentration in the soil was approximately 3% that of the waste heaps. Concentrations of Al, Co, Cu, Ni, Sb and Zn were highest in thalli of Peltigera, while the moss Racomitrium contained the highest content of Fe and Pb. Thalli of Cladina contained less metals than the cyanolichen Peltigera, and except for Zn metal concentrations in Cladina from the control locality were lower than in thalli of the same species from copper mine heaps. Regardless of the species or locality, the composition of assimilation pigments and chlorophyll a fluorescence showed that the tested lichens and moss were in good physiological condition and adapted to increased copper levels in the soil. There were significantly different amounts of total free amino acids in Peltigera, Cladina and Racomitrium from the Cu-polluted field. However, differences in amount of free amino acids in control, as well as Cu-polluted thalli of Cladina were less pronounced. PMID:19595434

Backor, Martin; Klejdus, Borivoj; Vantová, Ivana; Kovácik, Jozef

2009-09-01

160

Effects of recombinant bovine somatotropin (rbST) and season on plasma and milk insulin-like growth factors I (IGF-I) and II (IGF-II) in lactating dairy cows  

Microsoft Academic Search

During two studies, effects of recombinant bovine somatotropin (rbST) on plasma and milk IGF's in cows adapted to summer (S; 12 cows) or winter (W; 12 cows) conditions were evaluated. Each study consisted of on-farm periods (30 days) followed by climatology chamber periods (CC; 30 days). Cows were given daily injections of rbST, Sometribove, USAN (25mg\\/day; 6 cows each study)

Robert J. Collier; M. A. Miller; C. L. McLaughlin; H. D. Johnson; C. A. Baile

2008-01-01

161

Cooling Dry Cows  

E-print Network

T he drop in milk production in the summer causes sig- nificant economic losses in the dairy industry. That decrease in production is brought on by heat stress, and studies have documented that cooling lactat- ing cows increases their milk pro... studies have investigat- ed whether cooling dry cows affects postpartum milk produc- tion and reproductive measures, but the results so far have been inconclusive. In deciding whether to install cooling systems for dry cattle, producers should consider...

Stokes, Sandra R.

2000-07-17

162

Addition of Sodium Bicarbonate to Rations of Pre and Postpartum Dairy Cows1  

Microsoft Academic Search

Sodium bicarbonate was added to complete mixed rations to evaluate the effect of buffer addition on adaptation to high-energy rations by dairy cows in early lactation. Forty-five Holstein cows were assigned to one of three treatment groups: control pre- and postpartum; control prepartum, buffer postpartum; and buffer pre- and postpartum. Rations consisted of 85% chopped grass hay: 15% concentrate prepartum

L. H. Kilmer; L. D. Muller; P. J. Wangsness

1980-01-01

163

Ovarian follicular cysts in dairy cows: An abnormality in folliculogenesis  

Microsoft Academic Search

Ovarian follicular cysts are a major reproductive problem in lactating dairy cows. The primary physiological defect leading to the formation of ovarian follicular cysts is a failure of the hypothalamus to trigger the preovulatory surge of luteinizing hormone (LH) in response to estradiol. The factor responsible for this hypothalamic defect may be progesterone. Intermediate levels of progesterone have been shown

W. J Silvia; T. B Hatler; A. M Nugent; L. F Laranja da Fonseca

2002-01-01

164

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)

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.

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

2012-03-01

165

A Model System for Studying the Transcriptomic and Physiological Changes Associated with Mammalian Host-Adaptation by Leptospira interrogans Serovar Copenhageni  

PubMed Central

Leptospirosis, an emerging zoonotic disease with worldwide distribution, is caused by spirochetes belonging to the genus Leptospira. More than 500,000 cases of severe leptospirosis are reported annually, with >10% of these being fatal. Leptospires can survive for weeks in suitably moist conditions before encountering a new host. Reservoir hosts, typically rodents, exhibit little to no signs of disease but shed large numbers of organisms in their urine. Transmission occurs when mucosal surfaces or abraded skin come into contact with infected urine or urine-contaminated water or soil. In humans, leptospires can cause a variety of clinical manifestations, ranging from asymptomatic or mild fever to severe icteric (Weil's) disease and pulmonary haemorrhage. Currently, little is known about how Leptospira persist within a reservoir host. Prior in vitro studies have suggested that leptospires alter their transcriptomic and proteomic profiles in response to environmental signals encountered during mammalian infection. However, no study has examined gene expression by leptospires within a mammalian host-adapted state. To obtain a more faithful representation of how leptospires respond to host-derived signals, we used RNA-Seq to compare the transcriptome of L. interrogans cultivated within dialysis membrane chambers (DMCs) implanted into the peritoneal cavities of rats with that of organisms grown in vitro. In addition to determining the relative expression levels of “core” housekeeping genes under both growth conditions, we identified 166 genes that are differentially-expressed by L. interrogans in vivo. Our analyses highlight physiological aspects of host adaptation by leptospires relating to heme uptake and utilization. We also identified 11 novel non-coding transcripts that are candidate small regulatory RNAs. The DMC model provides a facile system for studying the transcriptional and antigenic changes associated with mammalian host-adaption, selection of targets for mutagenesis, and the identification of previously unrecognized virulence determinants. PMID:24626166

Caimano, Melissa J.; Sivasankaran, Sathesh K.; Allard, Anna; Hurley, Daniel; Hokamp, Karsten; Grassmann, André A.; Hinton, Jay C. D.; Nally, Jarlath E.

2014-01-01

166

Photosynthetic Adaptation of Solanum dulcamara L. to Sun and Shade Environments: II. Physiological Characterization of Phenotypic Response to Environment.  

PubMed

Photosynthetic and growth properties of Solanum dulcamara L. were studied under controlled environments. The 200 experimentally tested plants were clonal replicates of five field-collected individuals, three from fully exposed habitats and two from deeply shaded habitats. After 4 weeks of growth in one of eight environmental treatments, each plant was measured for leaf adaxial and abaxial conductance to water vapor, specific leaf weight, chlorophyll per square decimeter of leaf, photosynthetic unit size, light-saturated photosynthetic rate, total leaf area, and total leaf, stem, and root dry weights. Changes in light level influenced photosynthesis and growth of each plant more than changes in water availability or temperature. It is strongly suggested that the primary adaptive response of the tested individuals to changes in levels of light involves the regulation of leaf thickness. PMID:16660909

Clough, J M; Alberte, R S; Teeri, J A

1979-07-01

167

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

PubMed Central

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

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

2011-01-01

168

Do Telomeres Adapt to Physiological Stress? Exploring the Effect of Exercise on Telomere Length and Telomere-Related Proteins  

PubMed Central

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

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

2013-01-01

169

Functional evidence for physiological mechanisms to circumvent neurotoxicity of cardenolides in an adapted and a non-adapted hawk-moth species.  

PubMed

Because cardenolides specifically inhibit the Na(+)K(+)-ATPase, insects feeding on cardenolide-containing plants need to circumvent this toxic effect. Some insects such as the monarch butterfly rely on target site insensitivity, yet other cardenolide-adapted lepidopterans such as the oleander hawk-moth, Daphnis nerii, possess highly sensitive Na(+)K(+)-ATPases. Nevertheless, larvae of this species and the related Manduca sexta are insensitive to injected cardenolides. By radioactive-binding assays with nerve cords of both species, we demonstrate that the perineurium surrounding the nervous tissue functions as a diffusion barrier for a polar cardenolide (ouabain). By contrast, for non-polar cardenolides such as digoxin an active efflux carrier limits the access to the nerve cord. This barrier can be abolished by metabolic inhibitors and by verapamil, a specific inhibitor of P-glycoproteins (PGPs). This supports that a PGP-like transporter is involved in the active cardenolide-barrier of the perineurium. Tissue specific RT-PCR demonstrated expression of three PGP-like genes in hornworm nerve cords, and immunohistochemistry further corroborated PGP expression in the perineurium. Our results thus suggest that the lepidopteran perineurium serves as a diffusion barrier for polar cardenolides and provides an active barrier for non-polar cardenolides. This may explain the high in vivo resistance to cardenolides observed in some lepidopteran larvae, despite their highly sensitive Na(+)K(+)-ATPases. PMID:23516239

Petschenka, Georg; Pick, Christian; Wagschal, Vera; Dobler, Susanne

2013-05-22

170

Functional evidence for physiological mechanisms to circumvent neurotoxicity of cardenolides in an adapted and a non-adapted hawk-moth species  

PubMed Central

Because cardenolides specifically inhibit the Na+K+-ATPase, insects feeding on cardenolide-containing plants need to circumvent this toxic effect. Some insects such as the monarch butterfly rely on target site insensitivity, yet other cardenolide-adapted lepidopterans such as the oleander hawk-moth, Daphnis nerii, possess highly sensitive Na+K+-ATPases. Nevertheless, larvae of this species and the related Manduca sexta are insensitive to injected cardenolides. By radioactive-binding assays with nerve cords of both species, we demonstrate that the perineurium surrounding the nervous tissue functions as a diffusion barrier for a polar cardenolide (ouabain). By contrast, for non-polar cardenolides such as digoxin an active efflux carrier limits the access to the nerve cord. This barrier can be abolished by metabolic inhibitors and by verapamil, a specific inhibitor of P-glycoproteins (PGPs). This supports that a PGP-like transporter is involved in the active cardenolide-barrier of the perineurium. Tissue specific RT-PCR demonstrated expression of three PGP-like genes in hornworm nerve cords, and immunohistochemistry further corroborated PGP expression in the perineurium. Our results thus suggest that the lepidopteran perineurium serves as a diffusion barrier for polar cardenolides and provides an active barrier for non-polar cardenolides. This may explain the high in vivo resistance to cardenolides observed in some lepidopteran larvae, despite their highly sensitive Na+K+-ATPases. PMID:23516239

Petschenka, Georg; Pick, Christian; Wagschal, Vera; Dobler, Susanne

2013-01-01

171

Mad Cow Disease (For Parents)  

MedlinePLUS

... Lessons? Visit KidsHealth in the Classroom What Other Parents Are Reading Measles: What to Know Vaccines: FAQs ... Checkups: What to Expect Mad Cow Disease KidsHealth > Parents > Infections > Bacterial & Viral Infections > Mad Cow Disease Print ...

172

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

USGS Publications Warehouse

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. ?? 2007 American Chemical Society.

Lerner, D.T.; Bjornsson, B.T.; McCormick, S.D.

2007-01-01

173

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...

174

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

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.

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

2005-04-01

175

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

PubMed Central

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

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

2015-01-01

176

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

PubMed

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

Müller, Bettina; Manzoor, Shahid; Niazi, Adnan; Bongcam-Rudloff, Erik; Schnürer, Anna

2015-01-01

177

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

PubMed

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

Nalcakan, Gulbin Rudarli

2014-12-01

178

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

PubMed Central

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

Nalcakan, Gulbin Rudarli

2014-01-01

179

Physiology Online  

NSDL National Science Digital Library

Physiology Online, the electronic information service of the Physiological Society, provides information about its three journals: Journal of Physiology, Proceedings of the Physiological Society, and Experimental Physiology. Also included are selected abstracts, as well as information about recent monographs, job listings (mostly in the U.K.), information about Society grants, a physiology file and software archive for both PC and Mac platforms, pointers to other physiology resources on the Internet, and a listing of upcoming meetings and conferences within the field.

180

Influence of resistance training volume and periodization on physiological and performance adaptations in collegiate women tennis players.  

PubMed

Few data exist on the long-term adaptations to heavy resistance training in women. The purpose of this investigation was to examine the effect of volume of resistance exercise on the development of physical performance abilities in competitive, collegiate women tennis players. Twenty-four tennis players were matched for tennis ability and randomly placed into one of three groups: a no resistance exercise control group, a periodized multiple-set resistance training group, or a single-set circuit resistance training group. No significant changes in body mass were observed in any of the groups throughout the entire training period. However, significant increases in fat-free mass and decreases in percent body fat were observed in the periodized training group after 4, 6, and 9 months of training. A significant increase in power output was observed after 9 months of training in the periodized training group only. One-repetition maximum strength for the bench press, free-weight shoulder press, and leg press increased significantly after 4, 6, and 9 months of training in the periodized training group, whereas the single-set circuit group increased only after 4 months of training. Significant increases in serve velocity were observed after 4 and 9 months of training in the periodized training group, whereas no significant changes were observed in the single-set circuit group. These data demonstrate that sport-specific resistance training using a periodized multiple-set training method is superior to low-volume single-set resistance exercise protocols in the development of physical abilities in competitive, collegiate women tennis players. PMID:11032216

Kraemer, W J; Ratamess, N; Fry, A C; Triplett-McBride, T; Koziris, L P; Bauer, J A; Lynch, J M; Fleck, S J

2000-01-01

181

GnRH-Induced Ca2+ Signaling Patterns and Gonadotropin Secretion in Pituitary Gonadotrophs. Functional Adaptations to Both Ordinary and Extraordinary Physiological Demands  

PubMed Central

Pituitary gonadotrophs are a small fraction of the anterior pituitary population, yet they synthesize gonadotropins: luteinizing (LH) and follicle-stimulating (FSH), essential for gametogenesis and steroidogenesis. LH is secreted via a regulated pathway while FSH release is mostly constitutive and controlled by synthesis. Although gonadotrophs fire action potentials spontaneously, the intracellular Ca2+ rises produced do not influence secretion, which is mainly driven by Gonadotropin-Releasing Hormone (GnRH), a decapeptide synthesized in the hypothalamus and released in a pulsatile manner into the hypophyseal portal circulation. GnRH binding to G-protein-coupled receptors triggers Ca2+ mobilization from InsP3-sensitive intracellular pools, generating the global Ca2+ elevations necessary for secretion. Ca2+ signaling responses to increasing (GnRH) vary in stereotyped fashion from subthreshold to baseline spiking (oscillatory), to biphasic (spike-oscillatory or spike-plateau). This progression varies somewhat in gonadotrophs from different species and biological preparations. Both baseline spiking and biphasic GnRH-induced Ca2+ signals control LH/FSH synthesis and exocytosis. Estradiol and testosterone regulate gonadotropin secretion through feedback mechanisms, while FSH synthesis and release are influenced by activin, inhibin, and follistatin. Adaptation to physiological events like the estrous cycle, involves changes in GnRH sensitivity and LH/FSH synthesis: in proestrus, estradiol feedback regulation abruptly changes from negative to positive, causing the pre-ovulatory LH surge. Similarly, when testosterone levels drop after orquiectomy the lack of negative feedback on pituitary and hypothalamus boosts both GnRH and LH secretion, gonadotrophs GnRH sensitivity increases, and Ca2+ signaling patterns change. In addition, gonadotrophs proliferate and grow. These plastic changes denote a more vigorous functional adaptation in response to an extraordinary functional demand. PMID:24137156

Durán-Pastén, Maria Luisa; Fiordelisio, Tatiana

2013-01-01

182

Insights into the physiology and ecology of the brackish-water-adapted Cyanobacterium Nodularia spumigena CCY9414 based on a genome-transcriptome analysis.  

PubMed

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

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

183

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

PubMed Central

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

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

184

Adipose tissue depots of Holstein cows are immune responsive: Inflammatory gene expression in vitro  

Microsoft Academic Search

The transcriptional response of adipose tissue depots with respect to their immune responsiveness in dairy cows remains largely unknown. Thus, we examined mRNA expression and responsiveness of subcutaneous (SUB) and mesenteric (MES) adipose tissue from nonpregnant dairy cows to a short-term (2h), in vitro lipopolysaccharide (LPS) challenge (20?g\\/mL in physiological saline). Abundance of mRNA for tumor necrosis factor-? (TNFA), interleukin-6

M. Mukesh; M. Bionaz; D. E. Graugnard; J. K. Drackley; J. J. Loor

2010-01-01

185

Kinematics - Roller-Skating Cow  

NSDL National Science Digital Library

The representation depicts the position and velocity of a roller-skating cow as it travels in a horizontal direction. The student can select the initial position, velocity, and acceleration of the cow. As the cow moves forward according to the parameters set by the student, a position-time graph is created. A velocity-time graph positioned next to the position-time graph is simultaneously created.

186

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

PubMed

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

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

2015-03-01

187

Physiological characteristics of cassava tolerance to prolonged drought in the tropics: implications for breeding cultivars adapted to seasonally dry and semiarid environments  

Microsoft Academic Search

The paper summarizes research conducted at International Center for Tropical Agriculture (CIAT) on responses of cassava to extended water shortages in the field aided by modern gas-exchange and water-relation techniques as well as biochemical assays. The aim of the research was to coordinate basic and applied aspects of crop physiology into a breeding strategy with a multidisciplinary approach. Several physiological

Mabrouk A. El-Sharkawy

2007-01-01

188

Prebreeding Immunization of Beef Cows  

Microsoft Academic Search

A number of infectious agents are potential threats to the fetus of a pregnant cow and may result in abortion. These agents include Leptospira sp., Campylobacter fetus and viruses such as infectious bovine rhinotracheitis (IBR) and bovine virus diarrhea (BVD). Maintenance in the cow of a high level of immunity to these agents during pregnancy can insure protection of the

Merlin Kaeberle; Dennis Maxwell; Ronald Sealock

1999-01-01

189

Procedures of Exercise Physiology Laboratories  

NASA Technical Reports Server (NTRS)

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.

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

1998-01-01

190

Variation in and relationships among feeding, chewing, and drinking variables for lactating dairy cows.  

PubMed

Twelve Holstein cows (63 DIM; 6 primiparous) were offered a common diet and monitored for 21 d (11 d of adaptation, 10 d of collection) with a data acquisition system to measure continuously feed and water intakes and chewing behavior. Objectives were to examine relationships among feeding behavior variables for noncompeting cows producing various quantities of milk and to determine experimental designs with adequate power to detect reasonable treatment differences in future experiments. Coefficients of variation across cows ranged from 5 to 41% for the variables studied. Milk production was correlated positively with DMI and water intake within and across parities. For multiparous cows, production was related positively to meal size (r = .78) and length of eating bouts (r = .75) and unrelated to meal number and eating rate. For primiparous cows, production tended to be related positively to meal number (r = .55) and eating rate (r = .87) and unrelated to meal size. Rumination and total time spent chewing per unit of DMI were correlated negatively (r = -.58) with milk production within and across parities. These correlations suggest that differences exist among cows for chewing efficiency. Reasons why high producing cows consume and chew more effectively deserve further study. Contrast differences of 10% of means for variables examined had an 80% probability of detection with a Latin square design utilizing 12 cows monitored for 5 d. PMID:8120182

Dado, R G; Allen, M S

1994-01-01

191

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

NASA Technical Reports Server (NTRS)

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.

2005-01-01

192

Sleep in Dairy Cows Emma Ternman  

E-print Network

Sleep in Dairy Cows Emma Ternman Faculty of Veterinary Medicine and Animal Science Department/Repro, Uppsala 2014 Cover: Ceres ­ my supermodel cow (photo: J. Lipka) #12;Sleep in Dairy Cows Abstract Little is known about rest and sleep in dairy cows, but it has been shown in other species that the total amount

193

Normal bacterial flora from vaginas of Criollo Limonero cows.  

PubMed

In order to describe the normal bacterial flora in vaginas of Criollo Limonero cows, 51 healthy multiparous cows, at least 90-day postpartum, were selected. Duplicated swabs (N = 102) were taken from the vaginal fornix of cows to perform aerobic and anaerobic cultures as well as conventional biochemical tests. Out of 102 swabs, bacterial growth was obtained in 55 (53.9%) while the remaining 47 (46.1%) did not exhibited any bacterial growth. Of the 55 bacterial growths, 23 (41.8%) were aerobic whereas 32 (58.1%) were anaerobic. Likewise, 29 (52.72%) of bacterial growths were pure and 26 (47.27%) were mixed. Under both aerobic and anaerobic conditions, Gram positive bacteria were predominant (81.82% and 73.08%, respectively) over Gram negative bacteria (18.18% and 26.92%, respectively). Isolated bacteria were Arcanobacterium pyogenes (22.92%), Staphylococcus aureus (15.63%), Staphylococcus coagulase negative (17.71%), Erysipelothrix rhusiopathiae (6.25%), Bacteroides spp. (13.54%), and Peptostreptococcus spp. (7.29%). In conclusion, normal vaginal bacterial flora of Criollo Limonero cows was predominantly Gram positive and included A. pyogenes, S. aureus, coagulase negative Staphylococcus, E. rhusiopathiae, Bacteroides spp., and Peptostreptococcus spp. In Criollo Limonero cattle, adaptive aspects such as development of humoral and physical mechanisms for defense, and bacterial adaptation to host deserve research attention. PMID:21082249

Zambrano-Nava, Sunny; Boscán-Ocando, Julio; Nava, Jexenia

2011-02-01

194

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

PubMed

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

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

195

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

PubMed

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

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

2013-12-01

196

Mad Cow Disease  

NSDL National Science Digital Library

BioEd Online is an â??educational resource for educators, students, and parentsâ? from the Baylor College of Medicine. This is an excellent place to find educational materials and current information in the field of biology. The â??Hot Topicsâ? section of this site focus on current events and issues in biology that are â??receiving national attention.â? Mad Cow Disease has remained a challenge to scientists and regulatory commissions since its discovery in 1986. This â??Hot Topicâ? on Mad Cow Disease was compiled by Sonia Clayton, PhD, James Denk, MA, and Nancy Moreno, PhD, and contains a brief discussion of the how the disease effects cattle and humans, as well as prevention information. Also included are references and links for further reading at the bottom of the page. On the right hand side of the page a related slide set is available for viewing as well as several links to related news stories.

Clayton, Sonia

2004-01-22

197

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

PubMed Central

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

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

2014-01-01

198

Evolution of Human Hypoxia Tolerance Physiology  

Microsoft Academic Search

Analysis of human responses to hypobaric hypoxia in different lineages (lowlanders, Andean natives, Himalayan natives, and East Africans) indicates ‘conservative’ and ‘adaptable’ physiological characters involved in human responses to hypoxia. Conservative characters, arising by common descent, dominant and indeed define human physiology, but in five hypoxia response systems analyzed, we also found evidence for ‘adaptable’ characters at all levels of

Peter W. Hochachka; C. Carlos Monge

199

The effect of floor surface on dairy cow immune function and locomotion score.  

PubMed

This study evaluated the effect of 2 dairy cow housing systems on cow locomotion, immune status, and expression of genes associated with lameness during the dry and periparturient periods. Cows were assigned to freestall housing with either rubber (RUB; n = 13) or concrete (CON; n = 14) at the feed-bunk and alley immediately after their first calving, and managed on this system during all subsequent lactations. At dry off, cows were moved to a straw bedded-pack dry cow pen, and remained there until about 2 d before subsequent calving. To investigate whether greater exposure to RUB or CON increased the differences between cows on each treatment, cows at the end of either their first (n = 16) or second (n = 11) lactations were included in the experiment. Locomotion scores and blood samples were obtained at -60 (beginning of the dry period), -30, 0 (after calving), +10 and +18 d relative to calving. Leukocyte counts were obtained by using an automated cell counter. Phagocytic activity, and cells positive for CD14 and CD18 expression were measured by flow cytometry using labeled microbeads and antibodies. Expression of tachikinin 1(TAC1), histamine receptor 1 (H1), and metalloproteinase (MMP)13 in blood leukocytes was estimated using quantitative real-time PCR. Treatment effects were determined using a repeated measures model. Provision of rubber flooring did not improve dairy cow locomotion during the subsequent study period. However, time relative to calving had an effect on locomotion score and speed, which were worst on d 0, probably because of the discomfort associated with calving. An interaction occurred between treatment and time for neutrophil and lymphocyte counts. The RUB cows had greater neutrophil and lesser lymphocyte numbers postpartum than CON. These cows also had more cells positive for CD14 postpartum compared with prepartum. Moreover, RUB cows showed upregulation of MMP13 and TAC1 compared with CON. These genes are associated with lameness and pain detection respectively. Greater neutrophil to lymphocyte ratios and CD14 expression are associated with physiological stress or with activated immunity. Rubber flooring is associated with an increase in activity and standing. This may have resulted in indications of physiological stress and upregulation of genes associated with lameness and pain for RUB cows. However, this study did not take into account the long-term effects of concrete or rubber flooring; for instance, occurrence of lameness or survivability within the herd. PMID:19700686

O'Driscoll, K K M; Schutz, M M; Lossie, A C; Eicher, S D

2009-09-01

200

Performance and nutrient intake of high producing Holstein cows consuming pasture or a total mixed ration.  

PubMed

We compared the intakes of nutrients by high producing Holstein cows consuming pasture or a full nutrient positive control ration (total mixed ration; TMR) and identified nutrients that limited the milk production of cows consuming the high quality pasture. Cows (n = 8) were adapted to an all pasture diet by incrementally reducing the amount of TMR fed over a 4-wk period. A control group of cows (n = 8) remained in confinement and was fed a TMR. The performance of grazing cows differed significantly from that of cows fed the TMR in dry matter (DM) intake (19.0 vs. 23.4 kg/d of DM), milk production (29.6 vs. 44.1 kg/d), milk protein content (2.61% vs. 2.80%), live weight (562 vs. 597 kg), and body condition score (2.0 vs. 2.5). The high quality of the pasture permitted cows to consume the same daily intakes of neutral detergent fiber and crude protein (kilograms per day) as cows fed the TMR, but the pasture provided 19% less DM, organic matter, and net energy for lactation. Predictions using National Research Council estimates and the Cornell Net Carbohydrate and Protein System model indicated that the supply of metabolizable energy was first-limiting for the milk production of cows consuming high quality pasture rather than the supply of metabolizable protein or amino acids. Although a daily intake of 19 kg of DM was achieved on spring pasture, the significant mobilization of energy reserves indicated that supplemental energy is required to achieve milk production greater than 30 kg/d from high producing Holstein cows on intensive grazing systems. PMID:9621244

Kolver, E S; Muller, L D

1998-05-01

201

Physiological Waterfalls  

ERIC Educational Resources Information Center

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)

Leith, David E.

1976-01-01

202

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

PubMed

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

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

2014-05-01

203

Feeding the Transition Dairy Cow  

E-print Network

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...

Stokes, Sandra R.

1999-09-20

204

Effect of temporary weaning duration on tonic LH secretion, estrus, and ovulation in anestrous postpartum beef cows  

E-print Network

EFFECT OF TEMPORARY WEANING DURATION ON TONIC LH SECRETION, ESTRUS AND OVULATION IN ANESTROUS POSTPARTUM BEEF COWS A Thesis TANDY EUZABETH SHIVELY Submitted to the Graduate College of Texas ASM University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE December t 987 Major Subject: Physiology of Reproduction EFFECT OF TEMPORARY WEANING DURATION ON TONIC LH SECRETION, ESTRUS AND OVULATION IN ANESTROUS POSTPARTUM BEEF COWS A Thesis by TANDY ELIZABETH...

Shively, Tandy Elizabeth

1987-01-01

205

Physiological Genomics  

NSDL National Science Digital Library

Five journals with free (or recently extended) online trial periods were recently announced; online content includes full text, figures, and tables. The American Physiological Society has announced free, online access to Physiological Genomics through December 31, 2001; full text and abstracts are available from 1999. The journal is published in conjunction with Stanford University's HighWire Press.

1969-12-31

206

Conservation physiology  

Microsoft Academic Search

Conservation biologists increasingly face the need to provide legislators, courts and conservation managers with data on causal mechanisms underlying conservation problems such as species decline. To develop and monitor solutions, conservation biologists are progressively using more techniques that are physiological. Here, we review the emerging discipline of conservation physiology and suggest that, for conservation strategies to be successful, it is

Martin Wikelski; Steven J. Cooke

2006-01-01

207

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

PubMed Central

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

Garssen, Johan

2014-01-01

208

Physiological adaptations in the lichens Peltigera rufescens and Cladina arbuscula var. mitis, and the moss Racomitrium lanuginosum to copper-rich substrate  

Microsoft Academic Search

Two lichen species (Peltigera rufescens and Cladina arbuscula subsp. mitis) and one moss species (Racomitrium lanuginosum) growing on a copper mine heaps (probably 200–300yr old) in the village of Špania dolina (Slovak Republic) were assessed for selected physiological parameters, including composition of assimilation pigments, chlorophyll a fluorescence, soluble proteins and free amino acid content. The lichen C. arbuscula subsp. mitis

Martin Ba?kor; Bo?ivoj Klejdus; Ivana Vantová; Jozef Ková?ik

2009-01-01

209

a Sensor Based Automatic Ovulation Prediction System for Dairy Cows  

NASA Astrophysics Data System (ADS)

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.

Mottram, Toby; Hart, John; Pemberton, Roy

2000-12-01

210

Blood plasma magnesium, potassium, glucose, and immunoreactive insulin changes in cows moved abruptly from barn feeding to early spring pasture  

SciTech Connect

Cations and immunoreactive insulin in plasma were measured in 35 lactating cows moved abruptly to early spring pasture. After change of cows from grass-clover hay to fescue-bluegrass pasture containing 22 to 31 g potassium/kg dry matter, immunoreactive insulin of 5 Holstein cows increased 30% in 5 days and averaged 45% above prepasture concentrations for 40 days. Magnesium averaged 44% below prepasture content of plasma during this period and was correlated negatively with potassium -.17 and immunoreactive insulin -.37. Thirty Hereford cows were changed from corn silage and grass-clover hay to wheat-rye pasture containing 3.06% potassium in the dry matter. Each day on pasture, 10 cows each were fed 2.3 kg cornmeal, 10 were given 30 g magnesium oxide by capsule, and 10 were given no supplement. After unsupplemented cows were moved to pasture, immunoreactive insulin rose 51% in 8 days and plasma magnesium fell 24%. Both supplements reduced immunoreactive insulin, but magnesium was maintained higher by magnesium oxide than by cornmeal. Injection of two Holstein cows with insulin (2 IU/kg body weight) reduced plasma concentrations of both potassium and mgnesium 20% below that of two cows injected with only physiological saline. Whether elevated plasma insulin may accelerate development of hypomagnesemia in cattle on spring pasture with relatively high potassium content has not been established.

Miller, J.K. (Comparative Animal Research Lab., Oak Ridge, TN); Madsen, F.C.; Lentz, D.E.; Wong, W.O.; Ramsey, N.; Tysinger, C.E.; Hansard, S.L.

1980-07-01

211

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

PubMed

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 (>10,000kg milk/305d) 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, 1wk 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 8wk 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

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

2015-03-01

212

Immune response of postpartum dairy cows fed flaxseed.  

PubMed

Thirty Holstein cows were allotted at calving to 10 groups of three cows blocked for similar calving dates to determine the effects of dietary fatty acids on functional properties of immunocompetent cells in early lactation and at breeding. Cows were assigned at calving to one of three isonitrogenous, isoenergetic, and isolipidic supplements based on either calcium salts of palm oil, Megalac, micronized soybeans, or whole flaxseed. On the day of AI and 20 d later, cows were injected with ovalbumin to measure the antibody response. Blood samples were taken at different times after calving (d 5, 21, 42, and 105) and after AI (d 0, 10, 20, and 40) for quantification of serum progesterone, fatty acids, and prostaglandin E2 concentrations. Isolated peripheral blood mononuclear cells were cultured to evaluate the proliferative response to concanavalin A and in vitro productions of interferon-gamma and prostaglandin E2. In general, feeding flaxseed increased serum omega-3 fatty acids concentration compared with feeding Megalac or soybeans, which decreased the omega-6 to omega-3 fatty acids ratio. There was a significant diet x day interaction for the proliferative response of mononuclear cells after calving and AI, indicating that cell responses from cows fed flaxseed were transiently reduced compared with those fed Megalac and soybeans. Moreover, during the breeding period, serum progesterone concentration was significantly greater in cows fed flaxseed compared with those fed Megalac, whereas serum concentration of prostaglandin E2 was significantly lower in cows fed flaxseed than in those fed Megalac or soybeans. Dietary treatments had no effect on the antibody response to ovalbumin and on in vitro productions of interferon-gamma and prostaglandin E2. However, interferon-gamma and prostaglandin E2 were impaired in the first 3 wk after parturition regardless of dietary treatment. These results suggest that changes in fatty acids, progesterone, and prostaglandins E2 concentrations in serum due to dietary treatment and physiological status influenced systemic immunity as shown by reduced proliferative response. However, other mechanisms must be considered and are discussed to explain dietary effect on lymphocyte proliferative response to mitogenic stimulation and other immune functions. PMID:12939089

Lessard, M; Gagnon, N; Petit, H V

2003-08-01

213

Nasal Physiology  

MedlinePLUS

... Introduction The physiologic function of the nose includes respiration, conditioning inspired air, vocal resonance, olfaction, nasal resistance, protection of the lower airway, and ventilation and drainage of the sinuses. RESPIRATION The nose ...

214

Synthetic Physiology  

E-print Network

Optogenetic tools are DNA-encoded molecules that, when genetically targeted to cells, enable the control of specific physiological processes within those cells through exposure to light. These tools can pinpoint how these ...

Boyden, Edward Stuart

215

Cold adaptations.  

PubMed

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

Launay, Jean-Claude; Savourey, Gustave

2009-07-01

216

Gene-Based Mapping and Pathway Analysis of Metabolic Traits in Dairy Cows  

PubMed Central

The metabolic adaptation of dairy cows during the transition period has been studied intensively in the last decades. However, until now, only few studies have paid attention to the genetic aspects of this process. Here, we present the results of a gene-based mapping and pathway analysis with the measurements of three key metabolites, (1) non-esterified fatty acids (NEFA), (2) beta-hydroxybutyrate (BHBA) and (3) glucose, characterizing the metabolic adaptability of dairy cows before and after calving. In contrast to the conventional single-marker approach, we identify 99 significant and biologically sensible genes associated with at least one of the considered phenotypes and thus giving evidence for a genetic basis of the metabolic adaptability. Moreover, our results strongly suggest three pathways involved in the metabolism of steroids and lipids are potential candidates for the adaptive regulation of dairy cows in their early lactation. From our perspective, a closer investigation of our findings will lead to a step forward in understanding the variability in the metabolic adaptability of dairy cows in their early lactation. PMID:25789767

Ha, Ngoc-Thuy; Gross, Josef Johann; van Dorland, Annette; Tetens, Jens; Thaller, Georg; Schlather, Martin; Bruckmaier, Rupert; Simianer, Henner

2015-01-01

217

PRINCIPAL COMPONENTS FOR COW SIZE AND SHAPE  

Microsoft Academic Search

SUMMARY Thirty-eight Hereford and 23 Charolais cows, 5 years or older, were maintained in drylot during the lactation (7 months) and postlactation (5 months) phases of a produc- tion cycle. Daily feed consumption was regu- lated to maintain all cows in similar fleshing conditions throughout the production cycle. Cows were weighed biweekly; average weights over the production cycle (12 months)

J. A. Carpenter; H. A. Fitzhugh; T. C. Cartwright; R. C. Thomas; A. A. Melton

2010-01-01

218

Differences in the Fecal Concentrations and Genetic Diversities of Campylobacter jejuni Populations among Individual Cows in Two Dairy Herds  

PubMed Central

Dairy cows have been identified as common carriers of Campylobacter jejuni, which causes many of the human gastroenteritis cases reported worldwide. To design on-farm management practices that control the human infection sourced from dairy cows, the first step is to acquire an understanding of the excretion patterns of the cow reservoir. We monitored the same 35 cows from two dairy farms for C. jejuni excretion fortnightly for up to 12 months. The objective was to examine the concentration of C. jejuni and assess the genetic relationship of the C. jejuni populations excreted by individual cows. Significant differences (P < 0.01) in C. jejuni fecal concentration were observed among the 35 cows, with median concentrations that varied by up to 3.6 log10 · g?1 feces. A total of 36 different genotypes were identified from the 514 positive samples by using enterobacterial repetitive intergenic consensus (ERIC)-PCR. Although 22 of these genotypes were excreted by more than one cow, the analysis of frequencies and distribution of the genotypes by model-based statistics revealed a high degree of individuality in the C. jejuni population in each cow. The observed variation in the frequency of excretion of a genotype among cows and the analysis by multilocus sequence typing (MLST) of these genotypes suggest that excretion of C. jejuni in high numbers is due to a successful adaptation of a particular genotype to a particular cow's gut environment, but that animal-related factors render some individual cows resistant to colonization by particular genotypes. The reasons for differences in C. jejuni colonization of animals warrant further investigation. PMID:22904055

Ross, Colleen M.; Pleydell, Eve J.; Muirhead, Richard W.

2012-01-01

219

Characteristics of temporal patterns of cortisol and luteinizing hormone in primiparous, postpartum, anovular, suckled, beef cows exposed acutely to bulls  

PubMed Central

Background The physiological mechanism by which bulls stimulate resumption of ovarian cycling activity in postpartum, anovular, suckled cows after calving may involve the concurrent activation of the hypothalamic-hypophyseal-ovarian (HPO) axis and hypothalamic-hypophyseal-adrenal (HPA) axis. Thus, the objectives of this experiment were to determine if characteristics of temporal patterns of cortisol and luteinizing hormone (LH) in postpartum, anovular, beef cows are influenced by acute exposure to bulls. The null hypotheses were that daily, temporal characteristics of cortisol and LH concentration patterns do not differ between cows exposed acutely to bulls or steers. Methods Sixteen cows were assigned randomly 67 +/- 4 (+/- SE) after calving to be exposed to bulls (EB, n = 8) or steers (ES, n = 8) 5 h daily for 9 d (D 0 to 8). Blood samples were collected daily from each cow via jugular catheters at 15-min intervals for 6 h from 1000 to 1600 h each day. The 5-h exposure period began 1 h after the start of the intensive bleeding period. Characteristics of cortisol and LH concentration patterns (mean, baseline, pulse frequency, pulse amplitude, and pulse duration) were identified by PULSAR analyses. Results Mean cortisol concentrations decreased (P < 0.05) in cows in both treatments from D 0 to D 2. Thereafter, mean cortisol concentrations stabilized and did not differ (P > 0.10) between EB and ES cows. The decrease in mean cortisol concentrations in EB and ES cows from D 0 to D 2 was attributed to cows acclimatizing to intensive blood sampling and handling procedures. Consequently, analyses for characteristics of cortisol and LH concentration patterns included D 2 through 8 only. Cortisol mean and baseline concentrations, and pulse amplitude did not differ (P > 0.10) between EB and ES cows. However, cortisol pulse duration tended to be longer (P = 0.09) and pulse frequency was lower (P = 0.05) in EB than ES cows. LH pulse frequency was greater (P = 0.06) in EB than ES cows. All other characteristics of LH concentration patterns did not differ (P > 0.10) between EB and ES cows. Characteristics of cortisol concentration patterns were not related to characteristics of LH concentration patterns for ES cows (P > 0.10). However, as cortisol pulse amplitude increased, LH pulse amplitude decreased (b1 = -0.04; P < 0.05) for EB cows. Conclusions In conclusion, exposing primiparous, postpartum, anovular, suckled cows to bulls for 5-h daily over a 9-d period did not alter mean concentrations of cortisol or LH compared to mean concentrations of cortisol and LH in cows exposed to steers. However, exposing cows to bull in this manner altered characteristics of temporal patterns of both LH and cortisol by increasing LH pulse frequency and decreasing cortisol pulse frequency. Interestingly, in cows exposed to bulls, as amplitude and frequency of cortisol pulses decreased, amplitudes of LH pulses increased and frequency of LH pulses tended to increase. Thus, the physiological mechanism of the biostimulatory effect of bulls may initially involve modification of the HPA axis and these changes may facilitate activation of the HPO axis and resumption of ovulatory cycles in postpartum, anovular, suckled cows. PMID:20642864

2010-01-01

220

Your Cow and Calf Business.  

E-print Network

; for example, per man-hour, per machine or per acre. The business of producing calves should be measured in terms of pounds of calf produced per cow. (Weaning weight is the average weight of all calves at an average age of 7 months. Percentage of calf... crop is based on the. number of calves born alive per 100 cows that were with bulls during the preceding breeding season.) 95 475 452 425 404 380 366 333 90 450 428 405 383 360 338 315 85 425 404 383 361 340 319 298 80 400 380 360 340 320 300 280...

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

1960-01-01

221

The physiological effects of IGF-1 (class 1:Ea transgene) over-expression on exercise-induced damage and adaptation in dystrophic muscles of mdx mice  

Microsoft Academic Search

Duchenne muscular dystrophy (DMD) is a genetic disorder in which muscle weakness and fragility contribute to ongoing muscle\\u000a degeneration. Although exercise-induced muscle damage is associated with adaptation that protects normal muscle from further\\u000a damage, exploiting this process to protect dystrophic muscle has been avoided for fear of inducing excessive muscle degeneration.\\u000a However, muscle-specific over-expression of the class 1:Ea isoform of

James A. Ridgley; Gavin J. Pinniger; Peter W. Hamer; Miranda D. Grounds

2009-01-01

222

Utilization of kura clover-reed canarygrass silage versus alfalfa silage by lactating dairy cows.  

PubMed

The mixture of kura clover (Trifolium ambiguum M. Bieb.) and reed canarygrass (Phalaris arundinacea L.) has proven to be extremely persistent in the northern United States, but information about dairy cow performance on this mixture is lacking. Twenty lactating Holstein cows were used in a crossover design to compare dry matter (DM) intake and milk production from diets containing kura clover-reed canarygrass silage (KRS) or alfalfa (Medicago sativa L.) silage (AS). Forages were cut, wilted, ensiled in horizontal plastic bags, and allowed to ferment for at least 50 d before beginning the feeding experiment. The KRS was approximately 40% kura clover and 60% reed canarygrass. Treatments were total mixed rations formulated with either 57% of total DM from 1) AS or 2) KRS. Experimental periods were 28 d, with the first 14 d for diet adaptation and the last 14 d for measurement of intake and milk production. The neutral detergent fiber (NDF) concentrations of AS and KRS were 37.3 and 47.3%, respectively. The fermentation analyses indicated that both silages underwent a restricted fermentation, producing primarily lactic acid and some acetic acid. Dry matter intake (24.2 vs. 22.8 kg) and 4% fat-corrected milk (32.8 vs. 30.9 kg) were significantly higher for cows fed AS than for cows fed KRS. Cows consumed less NDF (6.7 vs. 8.0 kg) and less digestible NDF (3.0 vs. 4.4 kg) when fed AS diets compared with KRS diets, but the pool of ruminally undegraded NDF was similar (3.7 kg) between diets. Cows produced 1.5 kg of milk/kg of DM consumed regardless of the diet, indicating that digestible NDF of KRS was utilized with similar efficiency as the cell wall constituents of AS, but the intake of cows fed KRS may have been limited by rumen fill. Milk fat concentration tended to be higher for cows fed AS, but the milk true protein concentration and yields of fat and protein did not differ by treatment. Milk urea nitrogen content was higher when cows consumed AS (16.4 mg/ dL) compared with KRS (13.4 mg/dL). The cows fed KRS consumed more NDF but less total DMI, based on the results from this trial with diets formulated to contain approximately 60% of DM as forage, resulting in slightly lower milk yields than cows fed excellent-quality AS. This grass-legume mixture has the potential to be a source of quality forage for dairy cows in regions where alfalfa persistence is a problem. PMID:18650290

Kammes, K L; Heemink, G B H; Albrecht, K A; Combs, D K

2008-08-01

223

Milk yield and composition from Angus and Angus-cross beef cows raised in southern Brazil.  

PubMed

This study assessed milk yield and composition of Angus and Angus-cross beef cows raised in southern Brazil. A total of 128 records were collected in 2 consecutive calving seasons from cows between 3 and 5 yr of age of 4 breed compositions: Angus (ANAN), Caracu × Angus (CRAN), Hereford × Angus (HHAN), and Nelore × Angus (NEAN). These cows were mated to Brangus (BN) or Braford (BO) bulls and managed under extensive grazing conditions in southern Brazil. Milk production of these cows was assessed by 2 procedures: indirectly by the calf weigh-suckle-weigh procedure (WD) and directly by machine milking (MM). Lactation curves were estimated using nonlinear regression and the following related traits were derived: peak yield (PY), peak week (PW), total yield at 210 d (TY210), and lactation persistence (PERS). Milk composition and calf weaning weight adjusted to 210 d (WW210) were also determined. The MM technique was considered more accurate because of lower standard errors of estimated means, greater statistical power, and greater correlation between TY210 and WW210 (0.50) compared to WD (0.36). Considering the more precise evaluation by MM, the CRAN and NEAN cows had greater TY210 (1070 and 1116 kg, respectively) and PY (8.1 and 7.8 kg, respectively) compared to ANAN and HHAN cows, which had 858 and 842 kg for TY210 and 6.6 and 6.3 kg for PY, respectively. The NEAN cows had the latest PW at 10.8 wk. Late-calving cows had 21% lower TY210 compared to cows that calved earlier. Milk composition was influenced by cow genotype, with CRAN and NEAN cows producing milk with greater fat (3.8 and 3.9%, respectively) and protein (3.2 and 3.1%, respectively) content compared to ANAN and HHAN cows. Regardless of the genotype, fat, protein, and total solids increased in concentration from beginning to end of lactation, while lactose content decreased. Crossbreeding of Angus with adapted breeds of taurine or indicine origin can be effective in increasing milk yield and nutrient content and, consequently, producing heavier calves at weaning under extensive grazing in southern Brazil and other similar subtropical climate regions. PMID:24753378

Rodrigues, P F; Menezes, L M; Azambuja, R C C; Suñé, R W; Barbosa Silveira, I D; Cardoso, F F

2014-06-01

224

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

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.

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

2012-01-01

225

Regulatory Physiology  

NASA Technical Reports Server (NTRS)

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.

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

226

Evolutionary physiology of bone: bone metabolism in changing environments.  

PubMed

Bone evolved to serve many mechanical and physiological functions. Osteocytes and bone remodeling first appeared in the dermal skeleton of fish, and subsequently adapted to various challenges in terrestrial animals occupying diverse environments. This review discusses the physiology of bone and its role in mechanical and calcium homeostases from an evolutionary perspective. We review how bone physiology responds to changing environments and the adaptations to unique and extreme physiological conditions. PMID:25559152

Doherty, Alison H; Ghalambor, Cameron K; Donahue, Seth W

2015-01-01

227

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)

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.

Lange, K. A.

1980-01-01

228

GENETIC ADAPTATION OF LIVESTOCK: THE POWER OF CHANGE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Observation of commercial cattle producers within defined production environments suggests phenotypic variation exists among cows in the ability to perform within that environment with minimal resource "supplementation". Commonly, those individuals that exhibit this ability are said to be adapted. ...

229

Fractal physiology  

Microsoft Academic Search

The nature of fractals and the use of fractals instead of classical scaling concepts to describe the irregular surfaces, structures, and processes exhibited by physiological systems are described. The mathematical development of fractals is reviewed, and examples of natural fractals are cited. Relationships among power laws, noise, and fractal time signals are examined

William Deering; Bruce J. West

1992-01-01

230

Quantification of training load, energy intake, and physiological adaptations during a rugby preseason: a case study from an elite European rugby union squad.  

PubMed

Rugby Union (RU) is a high-speed collision sport consisting of an intermittent activity profile. Given the extreme physical demands of the sport, significant emphasis is placed on players possessing high lean body mass while minimizing body fat. Anecdotally, the most significant changes in body composition are observed during the preseason; however, there are no objective data on the physiological demands and energy intake during this time. We therefore monitored 45 elite European RU players over the 10-week preseason period by assessing training load using Global Positioning System and session rate of perceived exertion (sRPE) while also assessing changes in anthropometry and physical performance. For forwards and backs, respectively, mean weekly distance covered was 9,774 m (1,404) and 11,585 m (1,810) with a total mean weekly sRPE of 3,398 (335) arbitrary units and 2,944 (410) arbitrary units. Mean daily energy intake was 14.8 MJ (1.9) and 13.3 MJ (1.9), carbohydrate (CHO) intake was 3.3 (0.7) and 4.14 (0.4) g·kg body mass, protein intake was 2.52 (0.3) and 2.59 (0.6) g·kg body mass, and fat intake was 1.0 (0.3) and 0.95 (0.3) g·kg body mass for forwards and backs, respectively. Markers of physical performance (1 repetition maximum strength, speed, and repeated sprint tests) and anthropometry (body fat and estimated lean mass) improved in all players. Interestingly, all players self-selected a "low" CHO "high" protein diet. Based on physiological improvements the training load and energy intake seems appropriate, although further research is required to evaluate if such energy intakes would also be suitable for match day performance. PMID:25029003

Bradley, Warren J; Cavanagh, Bryce P; Douglas, William; Donovan, Timothy F; Morton, James P; Close, Graeme L

2015-02-01

231

Circulatory physiology in the developing embryo.  

PubMed

Knowledge of early developmental circulatory physiology has lagged behind advances in molecular cardiology. Cardiovascular physiology changes during embryonic development in a highly complex and carefully orchestrated manner, tightly correlated with structural development. Circulatory changes in early development include increasing heart rate, preload, and cardiac output; decreasing peripheral resistance; and increasing ventricular compliance, paralleling the increasing metabolic needs of the growing embryo. Newer techniques and the recent ability to study mammalian models of development have led to further insight into changes in myocardial and peripheral vascular physiology. The next major challenges include understanding the mechanisms regulating cardiovascular hemodynamics, normal physiologic adaptation of the growing embryo, and the physiology of abnormal cardiovascular development. PMID:11801893

Phoon, C K

2001-10-01

232

Cardiac responses to palpation per rectum in lactating and nonlactating dairy cows.  

PubMed

Interest in the monitoring of heart rate variability (HRV) has increased recently, as it gives more detailed and immediate information about the level of stress than traditional behavioral or hypothalamus-pituitary-adrenal measures. In this study, we evaluated heart rate (HR) and parasympathetic HRV parameters to monitor cardiac stress responses to palpation per rectum (PPR) in lactating (LACT; n = 11) and nonlactating (NLACT; n = 12) dairy cows. Heart rate and HRV were recorded from 40 min before PPR until 120 min after it was completed. Heart rate, the root mean square of successive differences (RMSSD), and the high-frequency component (HF) of HRV were analyzed by examining 5-min time windows. To compare cardiac responses to PPR between groups, changes in HR and HRV parameters were calculated as area under the curve (AUC) for LACT and NLACT cows. An immediate increase in HR was detected during PPR in both LACT (+21.4 ± 2.4 beats/min) and NLACT cows (+20.6 ± 2.3 beats/min); however, no differences were found between groups on the basis of parameters of AUC. The increase in HR in both groups along with a parallel decrease in RMSSD (LACT cows: -5.2 ± 0.4 ms; NLACT cows: -5.1 ± 0.4 ms) and HF [LACT cows: -10.1 ± 0.8 nu (where nu = normalized units); NLACT cows: -16.9 ± 1.2 nu] during PPR indicate an increase in the sympathetic, and a decrease in the parasympathetic tone of the autonomic nervous system. The increase in RMSSD (LACT cows: +7.3 ± 0.7 ms; NL cows: +17.8 ± 2.2 ms) and in HF (LACT cows: +24.3 ± 2.6 nu; NLACT cows: +32.7 ± 3.5 nu) immediately after PPR indicated a rapid increase in parasympathetic activity, which decreased under the baseline values 10 min following PPR. The amplitude and the maximum RMSSD and HF values were greater in NLACT cows than in LACT animals, suggesting a higher short-term cardiac responsiveness of NLACT cows. However, the magnitude and the duration of the stress response were greater in LACT cows, as indicated by the analysis of AUC parameters (area under the HRV response curve and time to return to baseline). Cow response to the PPR was more prominent in parasympathetic HRV measures than in HR. Based on our results, the effect of PPR on the cows' cardiac stress responses may have an impact on animal welfare on dairy farms, and investigating the effect of lactation on the cardiac stress reactions could prove useful in modeling bovine stress sensitivity. Further research is needed to find out whether the differences due to lactation are physiological or management related. PMID:25200771

Kovács, L; T?zsér, J; Szenci, O; Póti, P; Kézér, F L; Ruff, F; Gábriel-T?zsér, Gy; Hoffmann, D; Bakony, M; Jurkovich, V

2014-11-01

233

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

SciTech Connect

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.

Wang, Hesheng, E-mail: hesheng@umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Feng, Mary [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Frey, Kirk A. [Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Ten Haken, Randall K.; Lawrence, Theodore S. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Cao, Yue [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan (United States)

2013-08-01

234

Partitioning of energy in pregnant beef cows during nutritionally induced body weight fluctuation.  

PubMed

The purpose of this study was to determine if the efficiency of energy retention in pregnant cows was dependent on the time during the pregnancy that feed was offered. Our hypothesis was that restricting feed intake during the second trimester of gestation and providing the saved feed during the third trimester was less energetically efficient than providing the feed during the second trimester. Twenty cows (4 breed composite: 1/4 Hereford, 1/4 Angus, 1/4 Red Poll, and 1/4 Pinzgauer) that had produced 1 calf before the study were fed a diet that consisted of (DM basis) 67.3% chopped corn silage, 27.0% alfalfa hay, 5.5% corn, and 0.2% NaCl. When the cows were 87 +/- 0.6 d pregnant, the first nutrient balance measurement was conducted. Six subsequent nutrient balance measurements were taken on d 122 +/- 0.6, 143 +/- 0.6, 171 +/- 0.6, 206 +/- 0.6, 241 +/- 0.6, and 262 +/- 0.6 of gestation. Each nutrient balance measurement consisted of a 96-h total collection of feces and urine and a 24-h indirect calorimetry measurement. Ten cows were fed for moderate BW gain during the entire pregnancy, and 10 cows were feed-restricted in the second trimester and realimented during the third trimester (low-high, L-H). The BW of the cows at parturition (559 +/- 14 kg) did not differ between treatments (P = 0.20). There was a general trend for the proportion of ME intake retained to decrease in moderate cows as pregnancy progressed. The proportion of ME intake retained in L-H cows decreased during the first 49 d of feed restriction, but the proportion of ME retained after 77 d of restriction was greater than that retained at 49 d of restriction. During realimentation, there were no time effects for efficiency of ME conversion to retained energy, but efficiency was greater for L-H cows than moderate cows (P < 0.001). The ability of the cow to adapt its energy metabolism during periods of moderate feed restriction and realimentation allows development of management strategies that alter the time interval of the production cycle during which supplemental feed is offered. Total savings in feed offered during the production year are minimal, but management strategies can be developed that shift which feed resources are being used. PMID:17998430

Freetly, H C; Nienaber, J A; Brown-Brandl, T

2008-02-01

235

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

PubMed Central

“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

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

2012-01-01

236

Muscle Physiology  

NSDL National Science Digital Library

The Muscle Physiology Lab at the University of California-San Diego provides this comprehensive source of information on the neuromuscular system. The Web site appears as a extensive menu of subtopics, each leading to pages of detailed text and diagrams. Students studying muscle structure and function should find this well-organized and authoritative resource extremely useful. The Web site also includes a search tool for quickly finding pages of interest, and a list of related links for additional information.

2000-01-01

237

Effect of a short dry period on milk yield and content, colostrum quality, fertility, and metabolic status of Holstein cows.  

PubMed

We evaluated the effect of shortening the dry period (DP) on milk and energy-corrected milk (ECM) yields, milk components, colostrum quality, metabolic status, and reproductive parameters. Primiparous (n=372) and multiparous (n=400) Israeli Holstein cows from 5 commercial dairy herds were subjected to a 60-d or 40-d DP. Cows within each herd were paired according to milk production, age, days in milk, and expected calving. Analysis of the data from all cows, irrespective of age, revealed significant differences in milk and ECM yields that favored the 60-d DP, with a prominent effect in 2 of 5 examined herds. In primiparous cows, milk and ECM yields were similar between groups in 4 of 5 farms. In multiparous cows undergoing a 60-d (vs. 40-d) DP, milk and ECM yields were higher in 3 herds. These differences could not be explained by milk and ECM yields in cows diagnosed with metritis, ketosis, and mastitis (defined by a somatic cell count threshold of 250,000 cell/mL), distribution of infected and noninfected cows, or new infections during DP and after calving. Including the milk and ECM yields from an average of 19.55 d from the previous lactation revealed higher milk and ECM yields for 40-d (vs. 60-d) DP cows in all herds. Analyzing 2 consecutive lactations revealed similar milk and ECM yields between groups in 4 out of 5 herds. In 1 herd, yields were higher in the 40-d compared with the 60-d DP group. One week after calving, the nonesterified fatty acid concentrations of 40-d DP cows were significantly lower than those of 60-d DP cows, indicating better postpartum energy balance. Colostrum quality, measured as IgG concentration, did not differ between the 2 DP groups. Cows assigned to 40-d DP had better reproductive performance, as reflected by fewer days to first insemination, a lower proportion with >90 d to first insemination, and fewer days to pregnancy. With respect to primiparous cows, a short DP increased conception rate after first artificial insemination and decreased the proportion of nonpregnant cows after 150 d in milk. In light of these findings, we suggest that a short DP be applied for its economic and physiological benefits. This is highly relevant to dairy herds located in regions such as Israel, Spain, and Florida that suffer from reduced milk production during the hot season. PMID:24630671

Shoshani, E; Rozen, S; Doekes, J J

2014-05-01

238

Adaptation to temperature stress and aerial exposure in congeneric species of intertidal porcelain crabs (genus Petrolisthes): correlation of physiology, biochemistry and morphology with vertical distribution  

PubMed

We examined physiological and biochemical responses to temperature and aerial exposure in two species of intertidal porcelain crabs (genus Petrolisthes) that inhabit discrete vertical zones. On the shores of the Northeastern Pacific, P. cinctipes (Randall) occurs under rocks and in mussel beds in the mid to high intertidal zone and P. eriomerus (Stimpson) occurs under rocks in the low intertidal zone and subtidally to 80 m. Because of their different vertical distributions, these two species experience very different levels of abiotic stress. Individuals of P. cinctipes can be emersed during every low tide, but P. eriomerus is only emersed during the lowest spring tides and on most days is not emersed at all. Temperatures measured underneath rocks in the mid intertidal zone were as high as 31 °C, 15 °C higher than maximal temperatures measured under rocks in the low intertidal zone. In air, at 25 °C, large specimens of P. cinctipes were able to maintain a higher respiration rate than similarly sized P. eriomerus. No interspecific differences in the respiratory response to emersion were seen in small specimens. Examination of the response of heart rate to temperature revealed that P. cinctipes has a 5 °C higher Arrhenius break temperature (ABT, the temperature at which there is a discontinuity in the slope of an Arrhenius plot) than its congener (31.5 °C versus 26.6 °C). The heart rate of P. cinctipes recovered fully after exposure to cold (1.5 °C), but the heart rate of P. eriomerus did not recover after exposure to 2 °C or cooler. The ABT of heart rate in P. cinctipes was very close to maximal microhabitat temperatures; thus, individuals of this species may be living at or near their thermal tolerance limits. P. cinctipes were able to maintain aerobic metabolism during emersion, whereas P. eriomerus shifted to anaerobic metabolism. A pronounced accumulation of whole-body lactate was found in specimens of P. eriomerus incubated in air at 25 °C over a 5 h period, but not in P. cinctipes similarly treated. P. cinctipes possesses a membranous structure on the ventral merus of each walking leg, but this structure is not found in P. eriomerus. To test the function of the leg membrane, we measured the aerial respiration rates and the lactate accumulation of P. cinctipes with their leg membranes obscured. These individuals had significantly lower aerial respiration rates at 30 °C than control crabs. Crabs with leg membranes obscured also accumulated a considerable amount of lactate during a 5 h period of emersion at 28 °C, but control crabs showed no accumulation under the same conditions. These data suggest that the leg membrane functions as a respiratory structure. The results of this study illustrate that a suite of morphological, physiological and biochemical features allows P. cinctipes to live higher in the intertidal region than P. eriomerus. PMID:9319758

Stillman; Somero

1996-01-01

239

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

PubMed Central

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

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

240

First report about the mode of action of combined butafosfan and cyanocobalamin on hepatic metabolism in nonketotic early lactating cows.  

PubMed

The primary aim was to investigate the effect of combined butafosfan and cyanocobalamin on liver metabolism in early lactating cows through mRNA expression measurements of genes encoding 31 enzymes and transport proteins of major metabolic processes in the liver using 16 multiparous early lactating dairy cows. The treatments included i.v. injection of 10 mL/100 kg of body weight combined butafosfan and cyanocobalamin (TG, n = 8) on 3 d consecutively at 25 ± 3 d in milk or injection with physiological saline solution similarly applied (CG, n = 8). Results include a higher daily milk production for TG cows (41.1 ± 0.9 kg, mean ± SEM) compared with CG cows (39.5 ± 0.7 kg). In plasma, the concentration of inorganic phosphorus was lower in the TG cows (1.25 ± 0.08 mmol/L) after the treatment than in the CG cows (1.33 ± 0.07 mmol/L). The plasma ?-hydroxybutyrate concentration was 0.65 ± 0.13 mmol/L for all cows before the treatment, and remained unaffected post treatment. The unique result was that in the liver, the mRNA abundance of acyl-coenzyme A synthetase long-chain family member 1, involved in fatty acid oxidation and biosynthesis, was lower across time points after the treatment for TG compared with CG cows (17.5 ± 0.15 versus 18.1 ± 0.24 cycle threshold, log(2), respectively). In conclusion, certain effects of combined butafosfan and cyanocobalamin were observed on mRNA abundance of a gene in the liver of nonketotic early lactating cows. PMID:21943742

Kreipe, L; Deniz, A; Bruckmaier, R M; van Dorland, H A

2011-10-01

241

Uterine prolapse and hypocalcemia in dairy cows.  

PubMed

Blood samples were collected from 53 dairy cows with uterine prolapse and from 53 cows with normal parturition (no uterine prolapse) matched by dairy as controls for various management programs among dairies. Cows with uterine prolapse had significantly lower total serum calcium content than did controls (P less than 0.01). Mean (+/- SEM) serum calcium content (mg/dl) for affected cows and controls were 6.08 (+/- 0.25) and 6.96 (+/- 0.20), respectively. Severe hypocalcemia (less than 4 mg/dl) was found in 10 (19%) of the affected cows, compared with 1 (1.8%) of the controls. Fifteen (28%) of the affected cows had moderate hypocalcemia (4.1 to 6.0 mg/dl), compared with 14 (26%) of the controls; 19 (36%) of the affected cows were mildly hypocalcemic (6.1 to 7.9 mg/dl), compared with 25 (47%) of the controls. Nine (17%) of the affected cows and 13 (25%) of the controls were within the normal range of calcium content (greater than 8 mg/dl). Nine of the affected cows were first-calf cows. The serum of these animals did not have significantly lower calcium concentrations, compared with controls matched by parity. Serum calcium values (mg/dl) for 9 first-calf cows and the 9 matched controls were 7.24 (+/- 0.42) and 7.00 (+/- 0.39), respectively. It was concluded that hypocalcemia was associated with uterine prolapse in multiparous dairy cows and, along with other factors, is involved as an etiologic factor for this puerperal condition. PMID:6511623

Risco, C A; Reynolds, J P; Hird, D

1984-12-15

242

A note on post partum utero vaginal prolapse in Gir cows: estimation of serum calcium, phosphorus, proteins, and cholesterol.  

PubMed

Reported are results obtained from determination of calcium, phosphorus, protein, and cholesterol in blood serum of 10 Gir cows with uterine prolapse. Particular reference is made to possible adverse effects of hypocalcaemia in conjunction with physiological stress resulting from pregnancy and parturition. PMID:2774812

Dhanotiya, R S; Srivastava, R K; Pandit, R K

1989-01-01

243

Necrotizing meningoencephalitis in a cow.  

PubMed

An 18-month-old Charolais cow developed depression and drooling and was submitted for necropsy after euthanasia. The cow was 1 of 50 moved between 2 farms approximately 5 days before the onset of clinical disease. Gross findings included swollen and hemorrhagic areas of malacia in the frontal, temporal, and parietal lobes of the cerebral cortex. Microscopically there was a necrotizing meningoencephalitis with intranuclear astrocytic and neuronal eosinophilic viral inclusions in the frontal, temporal, and parietal cerebral cortex as well as in the basal nuclei and thalamus. The gross and microscopic findings were consistent with necrotizing meningoencephalitis caused by bovine herpesvirus (BHV-1 or BHV-5), and the diagnosis was confirmed by detection of bovine herpesviral antigen on fresh samples of brain via fluorescent antibody test using a monoclonal antibody against BHV-1 glycoprotein C. PMID:23446433

Rissi, D R; Barros, C S L

2013-09-01

244

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

PubMed Central

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

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

2015-01-01

245

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

PubMed Central

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

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

2013-01-01

246

Prepartum and postpartum nutritional management to optimize fertility in high-yielding dairy cows in confined TMR systems.  

PubMed

The 6 to 8-week period centered on parturition, known as the transition or periparturient period, is critical to welfare and profitability of individual cows. Fertility of high-producing cows is compromised by difficult transitions. Deficiencies in either nutritional or non-nutritional management increase risk for periparturient metabolic disorders and infectious diseases, which decrease subsequent fertility. A primary factor impeding fertility is the extent of negative energy balance (NEB) early postpartum, which may inhibit timing of first ovulation, return to cyclicity, and oocyte quality. In particular, pronounced NEB during the first 10 days to 2 weeks (the time of greatest occurrence of health problems) is critical for later reproductive efficiency. Avoiding over-conditioning and preventing cows from over-consuming energy relative to their requirements in late gestation result in higher dry matter intake (DMI) and less NEB after calving. A pooled statistical analysis of previous studies in our group showed that days to pregnancy are decreased (by 10 days) by controlling energy intake to near requirements of cows before calving compared with allowing cows to over-consume energy. To control energy intake, total mixed rations (TMR) must be well balanced for metabolizable protein, minerals and vitamins yet limit total DM consumed, and cows must uniformly consume the TMR without sorting. Dietary management to maintain blood calcium and rumen health around and after calving also are important. Opportunities may exist to further improve energy status in fresh cows. Recent research to manipulate the glucogenic to lipogenic balance and the essential fatty acid content of tissues are intriguing. High-producing cows that adapt successfully to lactation can have high reproductive efficiency, and nutritional management of the transition period both pre- and post-calving must facilitate that adaptation. PMID:24844126

Drackley, J K; Cardoso, F C

2014-05-01

247

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

248

Effects of Corn and Soybean Meal Types on Rumen Fermentation, Nitrogen Metabolism and Productivity in Dairy Cows  

PubMed Central

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

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

2015-01-01

249

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

PubMed

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

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

2015-03-01

250

Characterization of ruminal dynamics in Holstein dairy cows during the periparturient period.  

PubMed

We used four pregnant Holstein cows to delineate ruminal adaptations as cows transitioned from one lactation to the next. Cows were fed typical diets through far-off and close-up dry periods and lactation. We measured ruminal characteristics on day 72 (late lactation), 51 (far-off dry), 23 and 9 (close-up dry) prepartum and on days 6, 20, 34, 48, 62, 76 and 90 postpartum (early lactation). Measurements included: ruminal fill (weight of actual contents), ruminal capacity (volume of rumen when fully filled), digestibilities and ruminal passage rates. Ruminal capacity tended to increase linearly during early lactation but was stable during dry and transition periods. Both total and liquid fill decreased linearly during the dry period, increased across parturition, and increased linearly through early lactation. Dry matter fill decreased as cows were fed the close-up diet at day 23 prepartum then increased near parturition and continued to increase across early lactation. Solid passage rate was greatest when cows were fed the close-up diet, and decreased throughout the transition period. In lactation, solid passage rate responded quadratically with peak at day 48 followed by decreases through day 90 postpartum. Liquid passage increased linearly across the transition period. Total tract organic matter digestibilities increased linearly over the dry period with significant increases prior to or immediately after parturition, then they remained relatively stable over early lactation until they increased at day 90. Fibre digestibilities demonstrated quadratic responses over early lactation, being higher on day 6 and day 90 than at other times. Starch digestibilities decreased linearly across both the dry and transition periods with decreases in lactation until day 62 followed by increases until day 90. High producing lactating dairy cows go through a multitude of ruminal adaptations, in terms of digestion, passage, capacity and fill, as they transition from one lactation to the next. PMID:21091551

Park, A F; Shirley, J E; Titgemeyer, E C; DeFrain, J M; Cochran, R C; Wickersham, E E; Nagaraja, T G; Johnson, D E

2011-10-01

251

Physiology for High School - The Physiology of Endurance Exercise: Research on the Last Frontier  

NSDL National Science Digital Library

The keynote presentation from EB 2009's Physiology for Life Science High School Teachers and Students Workshop. This presentation discusses how sled dogs use energy and adapt while running the 1,000 mile Iditarod Race in Alaska.

2009-04-18

252

Ovarian Follicular Cysts in Dairy Cows1  

Microsoft Academic Search

Ovarian follicular cysts are anovulatory follicular structures that occur in 10 to 13% of dairy cows. This review focuses upon the dynamics of cyst growth, development, and persistence as well as on associated endocrine and cellular mechanisms. During the es- trous cycle of cows, two to four waves of follicular growth occur. From a cohort of recruited follicles, one is

H. Allen Garverick

1997-01-01

253

Predicting the forage intake by lactating cows  

Technology Transfer Automated Retrieval System (TEKTRAN)

The current National Research Council (NRC) model to estimate the dry matter intake by cows is based on a single equation related to metabolic size and net energy density of the diet. However, research has indicated that the observed dry matter production by grazing cows can be influenced by animal...

254

Bleeding abomasal ulcers in dairy cows  

Microsoft Academic Search

The clinical signs and changes in blood and rumen fluid, and the results of therapy are described in 35 cows suffering from bleeding abomasal ulcer. The most important pathological findings were moderate to severe anaemia with pale mucous membranes and tachycardia, dark coloured to black faeces, a disturbed general condition and anorexia. Two of the cows were slaughtered immediately. The

U Braun; R Bretscher; D Gerber

1991-01-01

255

Green algal peritonitis in 2 cows.  

PubMed

Peritonitis due to infections with green algae was diagnosed at slaughter (in Texas and South Dakota) in 2 cows. One cow also had a generalized lymphadenitis. The intralesional green algae were histologically similar to those previously associated with bovine lymphadenitis. Amplified and sequenced algal ITS2 genes had higher homology with the genus Scenedesmus than with Chlorella. PMID:22688588

Hafner, S; Brown, C C; Zhang, J

2013-03-01

256

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 ...

257

CAMPYLOBACTER PREVALENCE IN LACATATING DAIRY COWS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The objective of the present study was to determine the prevalence of intestinal Campylobacter in lactating dairy cows from various regions of the United States. Fecal samples were collected from 720 cows on farms in the Northeast (4 farms), in the desert Southwest (3 farms), and in the Pacific Wes...

258

The feeding value of extruded corn grain in a corn silage-based ration for high-producing Holstein cows and heifers during mid lactation.  

PubMed

The objective of this study was to investigate the feeding value of extruded corn in a corn silage-based ration for high-producing Holstein cows during mid lactation. Sixteen multiparous and 8 primiparous Holstein cows (106 +/- 49.7 d in milk; 43.7 +/- 5.27 kg of milk/d) were paired based on parity, days in milk, milk production, and body condition score and assigned to 1 of 2 dietary treatments in a randomized block design for 10 wk including a 2-wk adaptation period. Cows were fed a total mixed ration and milked 3 times per day. Diets contained 44% forage (3:1; corn silage:grass silage), 44.7% grain, and either extruded corn (EXC) or finely ground corn (FGC) at 11.3% of ration dry matter. No significant differences were detected in dry matter intake, milk protein yields, fat-corrected milk yields, or body condition score between cows fed FGC and cows fed EXC. Multiparous cows fed EXC produced more milk during wk 3 through 8 with a reduced milk fat content compared with multiparous cows fed FGC. Milk protein content was greater for primiparous cows fed EXC during wk 5 through 8 compared with primiparous cows fed the FGC ration. The major effect of feeding 2.7 kg/d of EXC compared with FGC was an increase in milk production and a reduction in milk fat content for multiparous cows, and an increase in milk protein content for primiparous cows. PMID:17582131

Rezamand, P; Andrew, S M; Hoagland, T A

2007-07-01

259

Regulatory physiology discipline science plan  

NASA Technical Reports Server (NTRS)

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.

1991-01-01

260

Innate and adaptive immune responses to in utero infection with BVDV  

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 ...

261

Massive vulvar edema in 2 prepartum dairy cows  

PubMed Central

Two late gestation Holstein cows about to begin the third lactation developed massive vulvar edema. These were the only affected animals in the herd of 500 milking cows. The vulvar edema spontaneously regressed postpartum for both cows. Massive vulvar swelling is seldom observed in dairy cows in advanced pregnancy and is not described in the literature. PMID:24790232

Cheong, Soon Hon; Gilbert, Robert O.

2014-01-01

262

Massive vulvar edema in 2 prepartum dairy cows.  

PubMed

Two late gestation Holstein cows about to begin the third lactation developed massive vulvar edema. These were the only affected animals in the herd of 500 milking cows. The vulvar edema spontaneously regressed postpartum for both cows. Massive vulvar swelling is seldom observed in dairy cows in advanced pregnancy and is not described in the literature. PMID:24790232

Cheong, Soon Hon; Gilbert, Robert O

2014-05-01

263

Odontoblast physiology.  

PubMed

Odontoblasts are post-mitotic cells organized as a layer of palisade cells along the interface between the dental pulp and dentin. They are responsible for the formation of the physiological primary and secondary dentins. They synthesize the organic matrix of type I collagen and actively participate to its mineralization by secreting proteoglycans and non-collagenous proteins that are implicated in the nucleation and the control of the growth of the mineral phase. They also participate to the maintenance of this hard tissue throughout the life of the tooth by synthesizing reactionary dentin in response to pathological conditions (caries, attrition, erosion…). Besides these fundamental dentinogenic activities, odontoblasts were recently suspected to play a role as sensor cells. They are able to sense the bacteria invasion during caries and then to initiate the pulp immune and inflammatory response. They are also well equipped in ion channels implicated in mechanotransduction or nociception which make odontoblasts suitable candidates to sense external stimuli and to mediate tooth pain sensation. PMID:24361392

Bleicher, Françoise

2014-07-15

264

Changes in heat production by mature cows after changes in feeding level.  

PubMed

We hypothesized that adaptation of heat production in the realimented cow would occur over an extended period, and the length of time would be influenced by the level of feed. Our objectives were to quantify the changes in heat production of cows after feed restriction and to quantify the effect of level of realimentation on the dynamics of heat production in lightweight cows. Forty 4-yr-old nonpregnant, nonlacting cows (4-breed composite: 1/4 Hereford, 1/4 Angus, 1/4 Red Poll, and 1/4 Pinzgauer) were randomly assigned to receive 1 of 4 levels of a common alfalfa hay source. All cows were feed-restricted [50.0 g of DM/metabolic body size (MBS, kg of BW(0.75)); period 1], and individual fed heat production measurements were taken 0, 7, 13, 28, 56, and 91 d after feed restriction (period 1). In period 2, cows were fed their assigned feed level for their treatment after d 91 of restriction: 50.0 (T50.0), 58.5 (T58.5), 67.0 (T67.0), and 75.5 (T75.5) g of DM/MBS. Measures were taken at 7, 13, 28, 42, 56, 91, 119, and 175 d. In period 3, all cows were fed 75.5 g of DM/MBS after their 175-d measurement, and measures were taken at 7, 14, 28, 56, and 112 d later. In period 1, heat production decreased rapidly during the first 7 d of feed restriction, and heat production continued to decrease during the 91-d restriction. Heat production increased rapidly within the first 7 d, but chronic adaptation continued for T75.5 and T67.0 cows. In period 3, heat production increased rapidly during the first 7 d. Heat production scaled for metabolic body size tended to differ among treatments (P = 0.11). Daily heat production increased by 2.5 kcal/d. These data suggest that there is not a lag in heat production during realimentation and that increased recovered energy is associated with a rapid increase in heat production. PMID:16699100

Freetly, H C; Nienaber, J A; Brown-Brandl, T

2006-06-01

265

Comparison of long-term controlled internal drug release-based protocols to synchronize estrus and ovulation in postpartum beef cows.  

PubMed

Two experiments were conducted to examine the necessity of adding a GnRH injection to a 14-d controlled internal drug release (CIDR)-based protocol for synchronization of estrus and ovulation in postpartum beef cows. The experiments were designed to characterize long-term CIDR-based protocols in cyclic and noncyclic postpartum beef cows on the basis of estrous response, follicular dynamics, and serum steroid hormone concentrations. In Exp. 1 and 2, crossbred lactating beef cows (n = 40 and 38, respectively) were randomly assigned to 1 of 2 treatments by age, days postpartum (DPP), BCS, and estrous cyclicity status: 1) cows received a CIDR from d 0 to 14 followed by GnRH 9 d after CIDR removal (d 23) and PGF2? on d 30 (CIDR Select) or 2) CIDR administration from d 0 to 14 followed by PGF2? 16 d later (d 30; Show-Me-Synch). Estrus detection was performed using HeatWatch transmitters applied from CIDR removal to AI. Cows in Exp. 1 were artificially inseminated based on detected estrus whereas cows in Exp. 2 were inseminated at a fixed time. In both experiments, follicle turnover on d 25 of treatment was greater among CIDR Select-treated cows (P < 0.001) compared with Show-Me-Synch-treated cows. In Exp. 1, CIDR Select-treated cows tended to have a reduced (P = 0.06) variance for the interval to estrus after PGF2? than Show-Me-Synch-treated cows. Also, cows assigned to the CIDR Select protocol had greater concentrations of progesterone (P < 0.05) on the day before PGF2? administration as well as greater concentrations of estradiol-17? (P < 0.01) 48 h after PGF2? administration. In Exp. 2, mean dominant follicle diameter on d 23 and at fixed-time AI (FTAI) did not differ between treatments (P > 0.10), but Show-Me-Synch-treated cows had larger follicles at d 28 (P < 0.001) and tended to have larger follicles at PGF2? (d 30; P = 0.06) compared with cows assigned to CIDR Select. In summary, the administration of GnRH on d 23 of a long-term CIDR-based estrus synchronization protocol increased follicle turnover; however, both long-term CIDR-based protocols yielded similar physiological outcomes among estrous-cycling and anestrous postpartum beef cows. PMID:23572255

Nash, J M; Mallory, D A; Ellersieck, M R; Poock, S E; Smith, M F; Patterson, D J

2013-07-01

266

A model to optimise the requirements of lactating dairy cows for physically effective neutral detergent fibre.  

PubMed

This study modelled multiple physiological responses of dairy cows to physical and chemical characteristics of a diet aiming to optimise their requirements for physically effective neutral detergent fibre, expressed inclusive of particles-dry matter > 8 mm (peNDF > 8). Extensive research data, comprising a wide range of feeding conditions (n = 64 studies and 257 different dietary treatments), were used to parameterise the model, while statistical modelling was used to account for the inter- and intra-experiment variation as well as to derive the model estimates. Physiological thresholds and 'safety limits' of peNDF > 8 for maintaining different physiological variables were derived using non-linear statistical modelling. Results showed that peNDF > 8 content in the diet is a key factor stimulating rumination activity, maintaining optimal ruminal pH and promoting fibre digestion. Modelling data with regard to the association of fibre digestion and time duration of ruminal pH < 5.8 and dietary peNDF > 8 suggests that feeding of less than 13.7% peNDF > 8 (the lower 'safety limit') is critical to prevent depression of fibre digestion in dairy cows. The study also indicated that the beneficial effects of peNDF > 8 on ruminal pH and fibre digestion can be at the expense of the dry matter intake (DMI) level of high-producing cows when the peNDF > 8 threshold of 14.9% in the diet is exceeded. In terms of the optimisation of peNDF > 8 requirements, the modelling data suggest that feeding of 17-18.5% peNDF > 8 can be beneficial in maintaining ruminal pH, while allowing a relatively high DMI (22.3-22.7 kg x d(-1)) for average high-producing dairy cows. PMID:20722298

Zebeli, Qendrim; Mansmann, Dominik; Ametaj, Burim N; Steingass, Herbert; Drochner, Winfried

2010-08-01

267

Metabolic parameters and their relationship to energy balance in multiparous Simmental, Brown Swiss and Holstein cows in the periparturient period as influenced by energy supply pre- and post-calving.  

PubMed

A study was conducted to evaluate the effects of three energy supply (E) levels [low (L), medium (M), high (H)], both pre-partum (PRE) and post-partum (POST), and their interactions on metabolic parameters and energy balance (EB) in dairy cows of three breeds. In both phases, E levels applied to a total of 81 multiparous cows of breeds Simmental (SI), Brown Swiss (BS) and Holstein-Friesian (HF; n = 27 for each breed) were 75%, 100% and 125% of recommendations of the German Society of Nutrition Physiology, using a 3 × 3 factorial arrangement of treatments. During the pre-calving period, serum concentrations of non-esterified fatty acids (NEFA) were higher for L(PRE) cows, and glucose concentrations were elevated for H(PRE) cows. During the lactation period, NEFA concentrations were greatest for treatment L(POST). Mean concentrations of ?-hydroxybutyrate (BHB) were highest for cows of the L(POST) treatment, intermediate for M(POST) and lowest for H(POST). Glucose concentrations were lower for L(POST) cows. SI cows had lower BHB concentrations both pre- and post-calving and higher glucose concentrations during early lactation than the other breeds. BHB concentration POST was highest for BS cows. Restricted feeding PRE resulted in a better energy status of cows fed above energy requirements POST (E(PRE) × E(POST) interaction). HF cows had a higher EB pre-calving, whereas SI cows had a less negative EB during early lactation, compared with the other breeds respectively. Correlations of serum NEFA, BHB and glucose concentrations with EB were strongest during the transition period. Results suggest that controlling energy intake during the dry period might be advantageous for the energy status of dairy cows after calving, whereas energy restriction in early lactation leads to metabolic stress. Evidence is provided of a clear relationship between EB and the blood metabolites NEFA and BHB, especially in the transition period. PMID:24605925

Urdl, M; Gruber, L; Obritzhauser, W; Schauer, A

2015-02-01

268

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

PubMed

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

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

2014-09-01

269

Markers of gut mucosal inflammation and cow’s milk specific immunoglobulins in non-IgE cow’s milk allergy  

PubMed Central

Background Allergy to cow’s milk protein (CMP) may cause gastrointestinal (GI) symptoms in the absence of CMP specific IgE. The immunological mechanisms involved in such disease are not fully understood. Therefore we examined markers of gut mucosal inflammation and the immunoglobulin profiles in children with Gl symptoms suspected of cow’s milk protein allergy (CMPA). Patients and methods We prospectively recruited infants and young children (n?=?57; median age 8.7 months) with gastrointestinal complaints suspected of CMPA. The diagnosis of CMPA was made using the double-blind, placebo-controlled food challenge. Serum and stool samples were collected during CMP-free diet and after both placebo and active challenges. We analyzed the stool samples for calprotectin, human ?-defensin 2 and IgA. In serum, we analyzed the levels of ?-lactoglobulin and ?-casein specific IgA, and IgG antibodies (total IgG and subclasses IgG1 and IgG4). Control group included children with e.g. dermatological or pulmonary problems, consuming normal diets. Results Fecal calprotectin levels were higher in the challenge positive group (n?=?18) than in the negative (n?=?37), with respective geometric means 55 ?g/g [95% confidence interval 38–81] and 29 [24–36] ?g/g (p?=?0.0039), during cow’s milk free diet. There were no significant inter-group differences in the fecal ?-defensin and IgA levels. The CMP specific IgG and IgA were not elevated in patients with CMPA, but the levels of ?-lactoglobulin-IgG4 (p?=?0.0118) and ?-casein-IgG4 (p?=?0.0044), and total ?-casein-IgG (p?=?0.0054) and -IgA (p?=?0.0050) in all patient samples (regardless of CMPA diagnosis) were significantly lower compared to the control group using dairy products. Conclusions Despite cow’s milk elimination in children intolerant to cow’s milk there might be ongoing low-grade inflammation in the gut mucosa. CMP specific IgG or IgA should not be used to diagnose non-IgE CMPA. The observed frequency of impaired CMP specific total IgA, IgG and IgG4 production in patients following cow’s milk free diet warrants further studies. PMID:24598281

2014-01-01

270

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...

271

Cow-Calf Enterprise Standardized Performance Analysis  

E-print Network

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...

McCorkle, Dean; Bevers, Stan

2009-03-02

272

33 CFR 117.965 - Cow Bayou.  

Code of Federal Regulations, 2012 CFR

...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Texas § 117.965 Cow Bayou. The draws of the Orange County highway bridge, mile 2.9 at West Orange, and the S87...

2012-07-01

273

The Official Mad Cow Disease Home Page  

NSDL National Science Digital Library

A project of the Sperling Biomedical Foundation, the Mad Cow Disease homepage contains more than 7,600 articles on "mad cow and new variant Creutzfeldt-Jakob disease, prions, bovine spongiform encephalopathy, scrapie, BSE, CJD, CWD, TME, and TSE." Articles range from highlighting scientific results to heated debates surrounding the politically complex infectious disease challenge. For those wanting to keep a finger on the pulse of regional to global epidemics (such as mad cow disease) or others wanting to learn more about the many aspects of mad cow disease challenges, this is a fine place to get immersed (albeit in a freeform, rather than structured, way). A series of links points users to additional information.

274

Factors and Feeds for Supplementing Beef Cows  

E-print Network

decreases, and so does diet quality. Then, supple- mentation may become necessary even if animal numbers are reduced. Factors and Feeds for Supplementing Beef Cows Stephen P. Hammack and Ronald J. Gill* *Extension Beef Cattle Specialist and Extension Live...

Hammack, Stephen P.; Gill, Ronald J.

2000-05-03

275

Liver functional genomics in beef cows on grazing systems: novel genes and pathways revealed.  

PubMed

The adaptation of the liver to periods of negative energy balance is largely unknown in beef cattle on grazing systems. We evaluated liver transcriptome throughout gestation and early lactation of purebred and crossbred beef cows [Angus, Hereford, and their F1 crossbreeds (CR)], grazing high or low herbage allowances (HA) of native grasslands (4 and 2.5 kg dry matter/kg body wt annual mean; n = 16) using an Agilent 4 × 44k bovine array. A total of 4,661 transcripts were affected by days [272 ? 2.5-fold difference, false discovery rate (FDR) ? 0.10] and 47 pathways were altered during winter gestation (-165 to -15 days relative to calving), when cows experienced decreased body condition score, decreased insulin, and increased nonesterified fatty acid concentrations. Gluconeogenesis and fatty acid oxidation pathways were upregulated, while cell growth, DNA replication, and transcription pathways were downregulated (FDR ? 0.25). We observed only small changes in the liver transcriptome during early lactation (+15 to +60 days). A total of 225 genes were differentially expressed (47 ? 2-fold difference, FDR ? 0.10) between HA. The majority of those were related to glucose and pyruvate metabolism and were upregulated in high HA, reflecting their better metabolic status. Two genes were upregulated in CR cows, but 148 transcripts (74 ? 2-fold change difference, FDR ? 0.10) were affected by the HA and cow genotype interaction. The transcriptional changes observed indicated a complex and previously unrecognized, hepatic adaptive program of grazing beef cows in different nutritional environments. Novel target candidate genes, metabolic pathways, and regulatory mechanisms were reported. PMID:24326346

Laporta, Jimena; Rosa, Guilherme J M; Naya, Hugo; Carriquiry, Mariana

2014-02-15

276

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

NASA Astrophysics Data System (ADS)

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.

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

2013-09-01

277

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

PubMed

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

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

2013-09-01

278

The influence of cow factors on the incidence of clinical mastitis in dairy cows.  

PubMed

Many cow-specific risk factors for clinical mastitis (CM) are known. Other studies have analyzed these risk factors separately or only analyzed a limited number of risk factors simultaneously. The goal of this study was to determine the influence of cow factors on the incidence rate of CM (IRCM) with all cow factors in one multivariate model. Also, using a similar approach, the probability of whether a CM case is caused by gram-positive or gram-negative pathogens was calculated. Data were used from 274 Dutch dairy herds that recorded CM over an 18-mo period. The final dataset contained information on 28,137 lactations of 22,860 cows of different parities. In total 5,363 CM cases were recorded, but only 2,525 CM cases could be classified as gram-positive or gram-negative. The cow factors parity, lactation stage, season of the year, information on SCC from monthly test-day records, and CM history were included in the logistic regression analysis. Separate analyses were performed for heifers and multiparous cows in both the first month of lactation and from the second month of lactation onward. For investigating whether CM was caused by gram-positive or gram-negative pathogens, quarter position was included in the logistic regression analysis as well. The IRCM differed considerably among cows, ranging between 0.0002 and 0.0074 per cow-day at risk for specific cows depending on cow factors. In particular, previous CM cases, SCC in the previous month, and mean SCC in the previous lactation increased the IRCM in the current month of lactation. Results indicate that it is difficult to distinguish between gram-positive and gram-negative CM cases based on cow factors alone. PMID:18349231

Steeneveld, W; Hogeveen, H; Barkema, H W; van den Broek, J; Huirne, R B M

2008-04-01

279

Cardiovascular physiology and diseases of amphibians.  

PubMed

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

Heinz-Taheny, Kathleen M

2009-01-01

280

Effect of changes in diet energy density on feed intake, milk yield and metabolic parameters in dairy cows in early lactation.  

PubMed

The purpose of this experiment was to investigate how early lactating cows adjust their metabolism and production to acute, but moderate changes in the energy density of the diet. Sixty dairy cows were randomly assigned to one of four treatments: two change-over groups (HNH and NHN) and two control groups (HHH and NNN), where H and N refer to a high and normal energy density in the total mixed ration (TMR), respectively. The experimental period covered the first 9 weeks post calving, which was split up in three 3-week periods. Thus, cows assigned to HNH or NHN shifted TMR in weeks 4 and 7 after calving while cows assigned to HHH or NNN were fed the same TMR for all 9 weeks. Results from cows on treatment HNH were compared with group HHH while cows on treatment NHN were compared with group NNN. When the diet changed from N to H and H to N, cows increased and decreased their dry-matter intake (DMI), respectively compared with control groups. Cows adjusted milk yield accordingly to changes in DMI, although not always significantly. Energy-corrected milk yield was not significantly affected by any of the changes in the energy density of the diet but generally showed same tendencies as milk yield. Non-esterified fatty acids (NEFA), beta-hydroxybutyrate in blood and milk and triacylglycerol and glycogen content in the liver were not significantly affected by changes in the energy density of the diet, except from NEFA at one change. Glucose increased more when the diet changed from N to H and increased less when the diet changed from H to N, compared with control groups, although not always significantly. Collectively, these results suggest that cows adjust their DMI and partly milk yield according to the energy density of the diet and therefore only limited effects were observed in physiological parameters. PMID:22444331

Nielsen, N I; Friggens, N C; Larsen, T; Andersen, J B; Nielsen, M O; Ingvartsen, K L

2007-03-01

281

Breed and heterotic effects on productive longevity of beef cows  

E-print Network

managed in a dairy. Dairy cows are fed at a high plane of nutrition and Maree (1979) noted that cows fed ad libitum are more susceptible to diseases than cows that are limit fed. Etienne and Martin (1979) observed Angus cows for 14 to 19 yr... and required the females to wean a calf every year. Etienne and Martin (1979) were observing the effect that creep feeding replacement heifers had on lifetime performance of cows and they found that 60. 4% of the cows were culled because they were...

Rohrer, Gary Alan

1987-01-01

282

Effects of evaporative cooling on reproductive performance and milk production of dairy cows in hot wet conditions  

NASA Astrophysics Data System (ADS)

Fourteen animals of second and third lactation of Thai Friesian crossbred cows (87.5% Friesian × 12.5% Bos indicus) located at Sakol Nakhon Research and Breeding Centre, Department of Livestock Development, Ministry of Agriculture and Cooperatives, were divided randomly into two groups of seven each to evaluate the effects of evaporative cooling on reproductive and physiological traits under hot, humid conditions. Results indicated that installation of evaporating cooling in the open shed gave a further improvement in ameliorating heat stress in dairy cows in hot-wet environments by utilising the low humidity conditions that naturally occur during the day. The cows housed in an evaporatively cooled environment had both a rectal temperature and respiration rate (39.09°C, 61.39 breaths/min, respectively) significantly lower than that of the non-cooled cows (41.21°C; 86.87 breaths/min). The former group also had higher milk yield and more efficient reproductive performance (pregnancy rate and reduced days open) than the latter group. It is suggested that the non-evaporatively cooled cows did not gain benefit from the naturally lower heat stress during night time.

Khongdee, S.; Chaiyabutr, N.; Hinch, G.; Markvichitr, K.; Vajrabukka, C.

2006-05-01

283

Plasma thiobarbituric acid reactive substances, vitamin A and vitamin E levels and resumption of postpartum ovarian activity in dairy cows.  

PubMed

Vitamins with antioxidative functions are commonly used as supplements to improve fertility in dairy cows. However, according to field test results uncertainty exists about the effect of these vitamins, especially in vitamin A and vitamin E, on ovarian functional activity. This study was performed to reveal the physiological characteristics of cows receiving enough feed and the ovaries of which were activated in the early postpartum period. Six of 12 primiparous cows showing the corpus luteum on 25 to 27 days after parturition were classified as early responders (PER); the remaining six were classified as late responders (PLR). Among 11 multiparous cows, nine were early responders (MER), and the remaining two were late responders (MLR). Plasma concentration of thiobarbituric acid reactive substances (TBARS) in the PER were lower than those in the PLR (P<0.01). The ratio of plasma all-trans-retinol to intake ?-tocopherol or ?-carotene were increased in the following order: MERcows which were able to utilize antioxidants and energy from the feed efficiently may have earlier resumption of ovaries postpartum. PMID:24506096

Aoki, Mari; Ohshita, Tomoko; Aoki, Yasuhiro; Sakaguchi, Minoru

2014-05-01

284

Changes in milk proteome and metabolome associated with dry period length, energy balance, and lactation stage in postparturient dairy cows.  

PubMed

The early lactation period of dairy cows, which produce high quantities of milk, is normally characterized by an insufficient energy intake to cover milk production and maintenance requirements. Mobilization of body reserves occurs to compensate this negative energy balance (NEB), and probably as a consequence there is a higher susceptibility to diseases and metabolic disorders. There are several diagnostic methods to detect NEB, usually involving ketosis related parameters. Due to the easy availability of milk this is a preferred matrix, but simple and robust predictors of NEB level are missing. To better understand the physiological mechanism of NEB, milk of cows subjected to different dry period lengths, in different energy balance status and lactation stage, were analyzed by untargeted metabolomics and proteomics techniques. Milk of cows in severe NEB showed higher concentrations of acute phase response proteins, unsaturated fatty acids, and galactose-1-phosphate. Improved energy balance (EB) resulted in higher concentration of cholesterol, cholesterol synthesis related proteins, and stomatin. The presence of stomatin and galactose-1-phosphate in milk was strongly dependent on the EB of the cows. These novel and interesting findings warrant more in-depth research to assess their applicability as robust indicators of NEB in milk and to clarify the role of stomatin and galactose-1-phophate in milk of dairy cows in NEB. PMID:23738862

Lu, Jing; Antunes Fernandes, Elsa; Páez Cano, Ana Elizabeth; Vinitwatanakhun, Jantipa; Boeren, Sjef; van Hooijdonk, Toon; van Knegsel, Ariette; Vervoort, Jacques; Hettinga, Kasper Arthur

2013-07-01

285

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...

286

Structure of Cow-Calf Industry Profitability in the cow-calf business has been  

E-print Network

Structure of Cow-Calf Industry Profitability in the cow-calf business has been relatively low due performance analysis completed in 2008 revealed that beef herds in the southwestern United States had low profitability and a mean annual return on assets of 0.61 percent. Partly due to the complex nature

287

Effect of Dietary Phosphorus on Performance of Lactating Dairy Cows: Milk Production and Cow Health  

Microsoft Academic Search

The objective of this study was to measure cow re- sponse to feeding of two dietary concentrations of P, one of which was close to recent National Research Council requirements, and the other of which was well in excess of the requirement. Diets containing 0.37 or 0.57% P (dry basis) were fed to Holstein cows for the first 165 d

H. Lopez; F. D. Kanitz; V. R. Moreira; M. C. Wiltbank; L. D. Satter

2004-01-01

288

Cow’s Milk in Treatment of Moderate and Severe Undernutrition in Low-Income Countries  

Microsoft Academic Search

Cow’s milk products have a central role in treatment of under nutrition, and the introduction of products with a high milk content (F-100 and ready to use therapeutic foods) has resulted in marked improvements in weight gain and reduction in mortality. Milk also has a specific effect on linear growth. Milk protein has a high quality score (PDCAAS) and contains

Kim F. Michaelsen; Anne-Louise H. Nielsen; Nanna Roos; Henrik Friis; Christian Mølgaard

2011-01-01

289

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

PubMed

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

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

2011-08-01

290

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

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 (E?) and progesterone (P?) characterize endocrine changes in high producing cows. Similar changes have been reported in the repeat breeder cows. The abnormal changes in E? and P? 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

Katagiri, Seiji; Moriyoshi, Masaharu

2013-10-01

291

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

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

KATAGIRI, Seiji; MORIYOSHI, Masaharu

2013-01-01

292

Cow's milk allergy in Thai children.  

PubMed

Cow's milk allergy (CMA) is nowadays a common problem in Thai children. We reviewed medical records of patients with CMA from the Department of Pediatrics at King Chulalongkom Memorial Hospital of the past 10 years, from 1998 to 2007. The criteria for the diagnosis of CMA included: elimination of cow's milk formula resulting in improvement of symptoms, and: recurrence of symptoms after reintroduction of cow's milk by oral challenge or by accidental ingestion. Of the 382 children with a diagnosis of CMA, 168 were girls and 214 were boys. The average age at the time of diagnosis was 14.8 months (7 days-13 years). The average duration of symptoms before diagnosis was 9.2 months. A family history of atopic diseases was found in 64.2% of the patients. All of the mothers reported an increased consumption of cow's milk during their pregnancy. The most common symptoms were respiratory (43.2%) followed by gastrointestinal (GI) (22.5%) and skin manifestations (20.1%). Less common symptoms included failure to thrive (10.9%), anemia (2.8%), delayed speech due to chronic serous otitis media (0.2%) and anaphylactic shock (0.2%). A prick skin test with cow milk extract was positive in 61.4%. Exclusively breast-fed was found in 13.2% of the patients. Successful treatment included elimination of cow's milk and milk products and substitution with soy formula in 42.5%, partial hydrolysate formula (pHF) in 35.7%, extensive hydrolysate formula (eHF) in 14.2%, and amino acid formula in 1.7%. Continued breast feeding was successful in 5.9% (with maternal restriction of cow's milk and milk products). Our study demonstrates the variety of clinical manifestations of CMA in Thai children especially respiratory symptoms which are usually overlooked. PMID:19317338

Ngamphaiboon, Jarungchit; Chatchatee, Pantipa; Thongkaew, Thaneya

2008-12-01

293

Cow Dung Ingestion and Inhalation Dependence: A Case Report  

ERIC Educational Resources Information Center

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.

Khairkar, Praveen; Tiple, Prashant; Bang, Govind

2009-01-01

294

33 CFR 157.158 - COW operations: Changed characteristics.  

Code of Federal Regulations, 2010 CFR

...ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Cow Operations...the inspections under § 157.140 are recorded in the Crude Oil Washing Operations and Equipment Manual approved...

2010-07-01

295

33 CFR 157.148 - COW system: Evidence for inspections.  

Code of Federal Regulations, 2010 CFR

...CONTINUED) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Inspections § 157.148 COW system: Evidence for inspections....

2010-07-01

296

Physiology & Development of Chronic Fear  

E-print Network

Physiology & Development of Chronic Fear (Behavioral Neuroendocrinology Lab) Sonia Cavigelli (PI A Individual B interest fear physiology physiology Individual A Temperament, Physiology, and Health health health Overarching Question: How do individual difference in behavior and physiology influence health

Dennis, Nancy

297

Characterization of Dutch dairy farms using sensor systems for cow management.  

PubMed

To improve cow management in large dairy herds, sensors have been developed that can measure physiological, behavioral, and production indicators on individual cows. Recently, the number of dairy farms using sensor systems has increased. It is not known, however, to what extent sensor systems are used on dairy farms, and the reasons why farmers invest or not in sensor systems are unclear. The first objective of this study was to give an overview of the sensor systems currently used in the Netherlands. The second objective was to investigate the reasons for investing or not investing in sensor systems. The third objective was to characterize farms with and without sensor systems. A survey was developed to investigate first, the reasons for investing or not in sensor systems and, then, how the sensor systems are used in daily cow management. The survey was sent to 1,672 Dutch dairy farmers. The final data set consisted of 512 dairy farms (response rate of 30.6%); 202 farms indicated that they had sensor systems and 310 farms indicated that they did not have sensor systems. A wide variety of sensor systems was used on Dutch dairy farms; those for mastitis detection and estrus detection were the most-used sensor systems. The use of sensor systems was different for farms using an automatic milking system (AMS) and a conventional milking system (CMS). Reasons for investing were different for different sensor systems. For sensor systems attached to the AMS, the farmers made no conscious decision to invest: they answered that the sensors were standard in the AMS or were bought for reduced cost with the AMS. The main reasons for investing in estrus detection sensor systems were improving detection rates, gaining insights into the fertility level of the herd, improving profitability of the farm, and reducing labor. Main reasons for not investing in sensor systems were economically related. It was very difficult to characterize farms with and without sensor systems. Farms with CMS and sensor systems had more cows than CMS farms without sensor systems. Furthermore, farms with sensor systems had fewer labor hours per cow compared with farms without sensor systems. Other farm characteristics (age of the farmer, availability of a successor, growth in herd size, milk production per cow, number of cows per hectare, and milk production per hectare) did not differ for farms with and without sensor systems. PMID:25465556

Steeneveld, W; Hogeveen, H

2015-01-01

298

Embryo production and quality of Holstein heifers and cows supplemented with beta-carotene and tocopherol.  

PubMed

The hypothesis was that the intramuscular injection (i.m.) of beta-carotene associated to tocopherol improves cow (n=86) and heifer (n=91) embryo production and quality. Time of estrus was synchronized in animals with an ear implant with 3 mg of norgestomet associated with an i.m. injection of 6 mg of norgestomet and 10mg of estradiol valerate (CRESTAR, Intervert International B.V., Boxmeer, Holland) and superovulated by 8 i.m. FSH/LHp injections (400 IU-heifers and 500 IU-cows) in decreasing concentrations at 12h intervals. Animals were inseminated 12 and 24h after observed onset of estrus and embryos recovered 7 days later. Animals were randomly allocated to one of three treatments: (1) vegetable oil vehicle (control), (2) 800 mg of beta-carotene and 500 mg of tocopherol (T800) and (3) 1200 mg of beta-carotene and 750 mg of tocopherol (T1200). Supplemental injections were given at the day norgestomet implants were inserted and at first superovulatory injection. An index (Embryo Quality Index or EQI) was proposed to more precisely evaluate embryo quality (excellent*1 + good*2 + regular*3 + poor*4 + degenerate*5 + unfertilized ova*5)/total. There was an interaction between physiological stage (heifer or cow) and treatment on EQI (P=0.01) and on the proportion of viable embryos (P=0.03), where both variables were improved in T1200 cows, but not in heifers. The average EQI for heifers and cows in control, T800 and T1200 were 2.6+/-0.3 and 3.6+/-0.3; 2.5+/-0.3 and 3.6+/-0.3; 2.9+/-0.3 and 2.7+/-0.3, respectively. The average total number of viable embryos was greater (P=0.01) in supplemented cows (3.5+/-1.1; 5.4+/-1.4 and 7.5+/-1.2 in control, T800 and T1200, respectively), but less (P=0.01) in heifers (7.5+/-1.2; 5.6+/-1.2 and 4.0+/-1.1 in control, T800 and T1200, respectively). Supplementation injections of beta-carotene associated to tocopherol improved embryo quality in superovulated Holstein cows, in the present experimental conditions and may be advantageous in similar embryo production systems. However, at dosages applied in the present experiment, this treatment should not be recommended for nulliparous heifers. PMID:17485181

Sales, J N S; Dias, L M K; Viveiros, A T M; Pereira, M N; Souza, J C

2008-06-01

299

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

PubMed

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

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

2014-02-01

300

physiologyINFO.org  

NSDL National Science Digital Library

What is physiology exactly? It's a good question, and one that is answered quite thoroughly on this website provided by The American Physiology Society (APS). The homepage starts things off with a basic introduction to physiology, complete with a pronunciation guide for the actual word. Moving on, the site contains four primary sections: "What is Physiology?", "Current Research", "Milestones in Physiology" and "Research Issues". The first section expands on the site's introduction by offering information on the questions physiologist ask, along with links to some online experiments culled from physiologists around the world. The "Current Research" section offers white papers from the APS, links to relevant journals, and abstracts from recently published physiology papers. Visitors will also want to look over the "Milestones in Physiology" area, as they can browse the timeline of physiology and also read 46 classic research articles taken from the American Journal of Physiology archives.

301

Influence of Dietary Sodium and Potassium Bicarbonate and Total Potassium on Heat-Stressed Lactating Dairy Cows1  

Microsoft Academic Search

Objectives were to study effects of heat stress, 0 or .85% sodium bicarbonate, 0 or 1.0% potassium bicarbonate, and 1.0 or 1.5% total dietary potassium on production and physiological responses of dairy cows. Eighteen lactating Holsteins were assigned to shade (control) or no shade (heat stress) lots continuously for three consecutive 35-day periods and to different dietary treatments each period.

P. L. Schneider; D. K. Beede; C. J. Wilcox; R. J. Collier

1984-01-01

302

Lafora disease in the cow?  

PubMed

Lafora disease in man is an autosomal recessive defect which affects carbohydrate metabolism and results in a progressive, ultimately fatal neurological condition. It is characterized histologically by intraneuronal cytoplasmic polyglucosan inclusions (Lafora bodies). Similar inclusions have been seen in association with neurological signs in other species, including the dog, the cockatiel and the cow. Polyglucosan bodies, however, are not always considered to be disease specific, and have also been reported as an age-related change in cats, dogs and man. The only recorded case in cattle to date has been a single animal in the USA. The present report records a case study of two animals with Lafora inclusion bodies, together with a survey of the occurrence of non-specific polyglucosan bodies in aged cattle. It is concluded that the inclusions in the two putative cases of Lafora disease were not non-specific age-related changes, and that these cases represent the first report of the disease in cattle in the UK. PMID:8056873

Simmons, M M

1994-05-01

303

The amount of shade influences the behavior and physiology of dairy cattle.  

PubMed

The objective was to understand how the amount of shade (shade cloth blocking 99% of solar radiation) influenced the behavior and physiology of Holstein-Friesian dairy cattle managed on pasture. We compared behavior, body temperature, and respiration rate of cattle provided with 1 of 3 treatments for 5 d: access to 2.4m(2) or 9.6m(2) shade/cow, or no shade (n=4 groups/treatment, 10 animals/group). Behavioral observations were carried out between 1000 and 1550h. Cows spent more than twice as much time in the larger shade (24 vs. 50% of observations for 2.4m(2) and 9.6m(2) shade/cow, respectively, SED: 1.7%) and engaged in fewer aggressive interactions when more shade was provided (10.7 vs. 3.2 aggressive interactions/m(2) during 5.8h of observation for 2.4m(2) and 9.6m(2) shade/cow, respectively, SED: 3.16 interactions/m(2)). Time around the water trough increased when little or no shade was provided (11, 5, and 2% of observations within 4.5m of water trough for no shade, 2.4m(2), and 9.6m(2) shade/cow, SED: 2.4%). Respiration rate was higher when cows had less shade available (62, 57, and 51 breaths/min for no shade, 2.4m(2), and 9.6m(2) shade/cow, respectively, SED: 2.1 breaths/min). All cows used the shade more when 9.6m(2) shade/cow was provided; simultaneous use was observed in 15 versus 0% of observations in the 9.6m(2) and 2.4m(2) treatments on the warmest day, respectively. Weather conditions influenced both the behavioral and physiological responses, and these changes were more pronounced when less or no shade was available. Cows spent more time in shade and less time lying with increasing heat load. In addition, aggressive interactions in the shade, time around the water trough, mean body temperature, and respiration rate increased with environmental heat load. Our findings highlight the importance of determining and providing an effective amount of shade to cattle. PMID:20059911

Schütz, K E; Rogers, A R; Poulouin, Y A; Cox, N R; Tucker, C B

2010-01-01

304

The Botanical Garden - A Tool to Teach Systematics, Physiology and a Lot More  

NSDL National Science Digital Library

As the UBC botanical gardens are arranged, there exists multiple teaching opportunities in areas such as: systematics, domesticated plants, environmental and physiological adaptations, micropropagation, biotechnology and others.

Iain E.P. Taylor (University of British Columbia; )

1988-06-06

305

Treatment of Cow's Milk Protein Allergy  

PubMed Central

The diagnosis and treatment of cow's milk protein allergy (CMPA) is still a challenge. A systematic literature search was performed using Embase, Medline, The Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Clinical Trials for the diagnosis and treatment of cow's milk allergy (CMA). Since none of the symptoms of CMPA is specific and since there is no sensitive diagnostic test (except a challenge test), the diagnosis of CMPA remains difficult. A "symptom-based score" is useful in children with symptoms involving different organ systems. The recommended dietary treatment is an extensive cow milk based hydrolysate. Amino acid based formula is recommended in the most severe cases. However, soy infant formula and hydrolysates from other protein sources (rice) are gaining popularity, as they taste better and are cheaper than the extensive cow's milk based hydrolysates. Recent meta-analyses confirmed the safety of soy and estimate that not more than 10-15% of CMPA-infants become allergic to soy. An accurate diagnosis of CMA is still difficult. The revival of soy and the development of rice hydrolysates challenge the extensive cow's milk based extensive hydrolysates as first option and amino acid formula. PMID:24749081

De Greef, Elisabeth; Devreker, Thierry

2014-01-01

306

Regulation of Adult Physiology and Behavior in Drosophila melanogaster  

E-print Network

The physiological responses involved in mediating adaptive change due to varying environmental conditions or social interactions are complex and involve integration of numerous signaling pathways. With Drosophila melanogaster, I can investigate...

Schwedes, Christoph 1980-

2012-10-26

307

PARTITIONING OF ENERGY DURING LACTATION OF PRIMIPAROUS BEEF COWS  

Technology Transfer Automated Retrieval System (TEKTRAN)

In order for a beef cow to continue in an annual production cycle, she must rebreed within three months after calving. Malnutrition during this period frequently results in failure of the cow to become pregnant. The energetic needs of the cow are increased by lactation and additional energy is req...

308

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 ...

309

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

ERIC Educational Resources Information Center

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…

Osterer, Irv

2011-01-01

310

33 CFR 157.124 - COW tank washing machines.  

Code of Federal Regulations, 2010 CFR

...machines in each tank must have sufficient nozzles with the proper diameter, working pressure...swash bulkheads. (g) Each single nozzle COW machine that is mounted to the deck...COW operations. (h) Each multi-nozzle COW machine that is mounted to the...

2010-07-01

311

Production Efficiency of Beef Cows through Mathematical Modeling and Genomics  

E-print Network

Production Efficiency of Beef Cows through Mathematical Modeling and Genomics For decades cows reside. With recent advances in genomics, the identification of intrinsic genetic factors Develop and evaluate the individual-based model· for production efficiency of beef cows using genomic

312

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...

313

Ability of buffalo and cow milks to form cream layer  

Microsoft Academic Search

Summary Cow milk is of higher ability for creaming and cream layer formation than buffalo milk. Pasteurization and boiling decrease the cow milk ability, while considerably increase the buffalo milk ability. Therefore, cow milk is more suitable for liquid milk processing, while buffalo milk faces the problem of forming a top thick cream layer. Buffalo milk is superior to produce

A. A. Ismail; M. S. El-Ganam; I. Sirry

1972-01-01

314

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...

315

Testing White Line Strength in the Dairy Cow  

Microsoft Academic Search

The tensile strength of 576 pieces of white line horn collected over 6 mo from 14 dairy cows restricted to parity 1 or 2 was tested. None of the cows had ever been lame. Seven cows were randomly assigned to receive 20 mg\\/d biotin supplementation, and 7 were not supple- mented. Hoof horn samples were taken from zones 2 and

L. E. Green; R. W. Blowey; A. J. Packington; R. H. C. Bonser

2004-01-01

316

Space colonization - Some physiological perspectives  

NASA Technical Reports Server (NTRS)

Physiological criteria determining the design of the habitat for a space colony with 10,000 people are discussed. Centrifugally generated earth-normal gravity, maximum ionizing radiation dose standards less than or equal to 0.5 rem/year (obtained with passive shielding), and an atmosphere with reduced nitrogen partial pressures were established as design requirements for the habitat. However, further research is needed to determine whether humans experience complete adaptation to weightlessness and whether there are long-term effects of breathing various atmospheric mixtures and pressures.

Winkler, L. H.

1978-01-01

317

Polyamines in plant physiology  

NASA Technical Reports Server (NTRS)

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.

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

1990-01-01

318

Productivity of F b1 sAngus-Jersey cows compared with Hereford cows under intensive and extensive management conditions  

E-print Network

PRODUCTIVITY OF Fl ANGUS-JERSEY COWS COMPARED WITH HEREFORD COWS UNDER INTENSIVE AND EXTENSIVE MANAGEMENT CONDITIONS A Thesis by Daniel Richard Ellison Submitted to the Graduate College of Texas A&M University in partial fulfillment... of the requirement for the degree of MASTER OE SCIENCE May 1974 Ma)or Sub)ect: Animal Breeding PRODUCTIVITY OF F ANGUS-JERSEY COWS COMPARED WITH HEREFORD l COWS UNDER INTENSIVE AND EXTENSIVE MANAGEMENT CONDITIONS A Thesis By DANIEL RICHARD ELLISON Approved...

Ellison, Daniel Richard

1974-01-01

319

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

PubMed

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

Armengol, Ramon; Fraile, Lorenzo

2015-05-01

320

Rectal mucosa in cows' milk allergy.  

PubMed Central

Eleven infants who were suspected clinically of having cows' milk protein sensitive enteropathy were fed with a protein hydrolysate formula for six to eight weeks, after which they had jejunal and rectal biopsies taken before and 24 hours after challenge with cows' milk protein. When challenged six infants (group 1) developed clinical symptoms and five did not (group 2). In group 1 the lesions developed in both the jejunal mucosa (four infants at 24 hours and one at three days), and the rectal mucosa, and the injury was associated with depletion of alkaline phosphatase activity. Infants in group 2 were normal. It seems that rectal injury that develops as a direct consequence of oral challenge with the protein in reactive infants may be used as one of the measurements to confirm the diagnosis of cows' milk protein sensitive enteropathy. Moreover, ingestion of such food proteins may injure the distal colonic mucosa without affecting the proximal small gut in some infants. PMID:2817945

Iyngkaran, N; Yadav, M; Boey, C G

1989-01-01

321

Experiences with adaptive statistical models for biosignals in daily life  

Microsoft Academic Search

We discuss the merits of adaptive statistical models for biosignals in a daily life context. Processing of this type of signals poses a number of challenges. First, it is clear that an adaptive model is needed to tailor for the differences in physiology between individuals, as well as adapt to someone's current physiological state. Second, in a daily life setting

Stijn de Waele; Gert-Jan de Vries; Mark JÃger

2009-01-01

322

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

E-print Network

(BCS) (n = 1473) were evaluated from 1994 to 2006 in 143 F1 cows sired by Brahman (B), Boran (Bo) and Tuli (T) bulls and born to Angus and Hereford cows. Mouth scores (MS) (n = 139) were assigned to the remaining cows in 2004 and 2005. Fixed effects...

Maiga, Assalia Hassimi

2007-04-25

323

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...

324

The effect of dose and type of cloprostenol on the luteolytic response of dairy cattle during the Ovsynch protocol under different oestrous cycle and physiological characteristics.  

PubMed

The objective of this study was to characterize the effect of dose and type of cloprostenol (CLO) on the luteolytic response of dairy cattle during the Ovsynch protocol under different oestrus cycle and physiological characteristics. Twelve non-lactating dairy cows and 111 lactating dairy cows were used in three experiments. In Experiment I, cows were synchronized so that they had only a 5.5- to 6-day-old corpus luteum (CL) at the time of the prostaglandin F2? (PGF2? ) treatment of Ovsynch. In Experiment II, cows were synchronized so that they had at least a CL of approximately 14 days old at the time of PGF2? treatment and an accessory CL if they had responded to the first GnRH of Ovsynch. Furthermore, in each experiment, cows received either a standard or a double dose of d-CLO as the luteolytic treatment. In Experiment III, lactating cows were blocked by parity and assigned to one of three luteolytic treatments during Ovsynch: 500 ?g d,l-CLO, 150 or 300 ?g of d-CLO. In Experiment I, the dose of d-CLO had an effect (p = 0.08) on the percentage of cows with full luteolysis, but not in Experiment II (p > 0.1). More cows in Experiment II had full luteolysis than did cows of Experiment I (87% vs 58%, respectively; p = 0.007). In Experiment III, 87.1%, 84.4% and 86.2% lactating dairy cows had full luteolysis and 37.8%, 36.8% and 36.1% of cows became pregnant after treatment with 500 ?g d,l-CLO, 150 or 300 ?g of d-CLO, respectively (p > 0.05). PMID:23691976

Valldecabres-Torres, X; Larrosa-Morales, P; Cuervo-Arango, J

2013-10-01

325

[Cow's milk protein allergy through human milk].  

PubMed

Cow's milk protein allergy (CMPA) is the first allergy that affects infants. In this population, the incidence rate reaches 7.5%. The multiplicity and aspecificity of the symptoms makes its diagnosis sometimes complicated, especially in the delayed type (gastrointestinal, dermatological, and cutaneous). CMPA symptoms can develop in exclusively breastfed infants with an incidence rate of 0.5%. It, therefore, raises questions about sensitization to cow's milk proteins through breast milk. Transfer of native bovine proteins such as ?-lactoglobulin into the breast milk is controversial: some authors have found bovine proteins in human milk but others point to cross-reactivity between human milk proteins and cow's milk proteins. However, it seems that a small percentage of dietary proteins can resist digestion and become potentially allergenic. Moreover, some authors suspect the transfer of some of these dietary proteins from the maternal bloodstream to breast milk, but the mechanisms governing sensitization are still being studied. Theoretically, CMPA diagnosis is based on clinical observations, prick-test or patch-test results, and cow's milk-specific IgE antibody concentration. A positive food challenge test usually confirms the diagnosis. No laboratory test is available to make a certain diagnosis, but the detection of eosinophil cationic protein (ECP) in the mother's milk, for example, seems to be advantageous since it is linked to CMA. Excluding cow's milk from the mother's diet is the only cure when she still wants to breastfeed. Usually, cow's milk proteins are reintroduced after 6 months of exclusion. Indeed, the prognosis for infants is very good: 80% acquire a tolerance before the age of 3 or 4 years. Mothers should not avoid dairy products during pregnancy and breastfeeding as preventive measures against allergy. PMID:22226014

Denis, M; Loras-Duclaux, I; Lachaux, A

2012-03-01

326

Physiological requirements of cricket  

Microsoft Academic Search

Despite its long history and global appeal, relatively little is known about the physiological and other requirements of cricket. It has been suggested that the physiological demands of cricket are relatively mild, except in fast bowlers during prolonged bowling spells in warm conditions. However, the physiological demands of cricket may be underestimated because of the intermittent nature of the activity

T. D. Noakes; J. J. Durandt

2000-01-01

327

Intestinal mucosal atrophy and adaptation  

PubMed Central

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

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

2012-01-01

328

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...

329

Priming the cow for mobilization in the periparturient period: effects of supplementing the dry cow with saturated fat or linseed.  

PubMed

High-producing dairy cows experience negative energy balance in early lactation. Dry-cow feeding management will affect the performance and metabolic status of dairy cows in the following early lactation. The present study evaluates dry-cow feeding strategies for priming lipid metabolism in the dairy cow to overcome the metabolic challenges in the following early lactation. Five weeks before expected calving, 27 cows were assigned to 1 of 3 isonitrogenous and isoenergetic dietary treatments: a low-fat control diet (dry-control); a high saturated fat diet (dry-HSF); and a high linseed diet (dry-HUF). The cows were fed the same TMR lactation diet after calving. The treatments were evaluated by performance and metabolic parameters in blood and liver. The cows fed dry-HSF and dry-HUF had significantly greater plasma nonesterified fatty acid concentrations compared with dry-control, and the dry-HUF cows had the greatest C18:3 concentrations in plasma in the prepartum period. Further, the cows fed dry-HSF and dry-HUF diets had a tendency for the greatest capacity for incomplete beta-oxidation of fatty acids in the liver in wk 3 prepartum. The plasma cholesterol concentration was greatest for cows fed dry-HSF in the prepartum period compared with those fed dry-control and dry-HUF. The cows fed dry-HSF had the lowest plasma nonesterified fatty acid and liver fat concentrations in early lactation compared with the cows fed dry-control and dry-HUF. Data in the literature and the present experiment indicate that supplementing dry cows with a saturated fatty acid source is a positive strategy for priming dairy cows for body fat mobilization in the following early lactation. PMID:18292259

Andersen, J B; Ridder, C; Larsen, T

2008-03-01

330

Neuronal Responses to Physiological Stress  

PubMed Central

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

Kagias, Konstantinos; Nehammer, Camilla; Pocock, Roger

2012-01-01

331

Comparative analyses of foregut and hindgut bacterial communities in hoatzins and cows  

PubMed Central

Foregut fermentation occurs in mammalian ruminants and in one bird, the South American folivorous hoatzin. This bird has an enlarged crop with a function analogous to the rumen, where foregut microbes degrade the otherwise indigestible plant matter, providing energy to the host from foregut fermentation, in addition to the fermentation that occurs in their hindguts (cecum/colon). As foregut fermentation represents an evolutionary convergence between hoatzins and ruminants, our aim was to compare the community structure of foregut and hindgut bacterial communities in the cow and hoatzin to evaluate the influences of host phylogeny and organ function in shaping the gut microbiome. The approach used was to hybridize amplified bacterial ribosomal RNA genes onto a high-density microarray (PhyloChip). The results show that the microbial communities cluster primarily by functional environment (foreguts cluster separately from hindguts) and then by host. Bacterial community diversity was higher in the cow than in the hoatzin. Overall, compared with hindguts, foreguts have higher proportions of Bacteroidetes and Spirochaetes, and lower proportions of Firmicutes and Proteobacteria. The main host differences in gut bacterial composition include a higher representation of Spirochaetes, Synergistetes and Verrucomicrobia in the cow. Despite the significant differences in host phylogeny, body size, physiology and diet, the function seems to shape the microbial communities involved in fermentation. Regardless of the independent origin of foregut fermentation in birds and mammals, organ function has led to convergence of the microbial community structure in phylogenetically distant hosts. PMID:21938024

Godoy-Vitorino, Filipa; Goldfarb, Katherine C; Karaoz, Ulas; Leal, Sara; Garcia-Amado, Maria A; Hugenholtz, Philip; Tringe, Susannah G; Brodie, Eoin L; Dominguez-Bello, Maria Gloria

2012-01-01

332

Determination of presence of Tritrichomonas foetus in uterine lavages from cows with reproductive problems.  

PubMed

The aim of this study was to determine the presence of Tritrichomonas foetus in two dairy herds on the Altiplano Cundiboyacense. Twenty-one low-volume uterine lavages from cows with a history of reproductive problems in two dairy herds located in the municipality of Sibaté (Cundinamarca) and Ventaquemada (Boyacá) were evaluated. In the first herd, 10 cows were sampled and in the second, 11 cows, based on three inclusion criteria. The uterine lavages were obtained through infusion of physiological saline solution into the uterine body. The samples were centrifuged and seeded in Tritrichomonas basal medium for 10-15 days at 37 ºC. The protozoa were evaluated on the day of sampling and 10 and 15 days after incubation by means of direct viewing under a dark-field microscope. Positive samples were stained with Wright and Lugol to identify the morphological characteristics. This study showed that T. foetus was present in 61.8% of the animals sampled. The determination that T. foetus was present in 61.8% of the samples analyzed is a significant finding given that in the herds evaluated, this agent had not previously been diagnosed. PMID:23070427

González-Carmona, Lady Carolina; Sánchez-Ladino, Milena Jineth; Castañeda-Salazar, Rubiela; Pulido-Villamarín, Adriana Del Pilar; Guáqueta-Munar, Humberto; Aranda-Silva, Moisés; Rueda-Varón, Milton Januario

2012-01-01

333

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...

334

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...

335

Cow attributes, herd management, and reproductive history events associated with abortion in cow-calf herds from Western Canada.  

PubMed

The primary objective of this study was to identify herd management and cow characteristics that are associated with abortion in cow-calf herds in Western Canada. Reproductive events were closely monitored in 29,713 cows in 203 herds from the beginning of the breeding season in 2001 through the calving season in 2002. Herd management and cow-level risk factors such as age, body condition score, and previous reproductive history were measured through a series of herd visits by project personnel and detailed individual animal records maintained by the herd owner. Pregnancy status was assessed in fall of 2001 by the herd veterinarian. Cows most likely to abort were replacement heifers, cows that were more than 10 years of age, cows with a body condition score of less than or equal to or 5 of 9 at pregnancy testing, or with twin pregnancies. Cows vaccinated for bovine viral diarrhea virus and infectious bovine rhinotracheitis and bred on community pastures were less likely to abort than cows from community pastures that were not vaccinated. Cows bred on community pastures that were not vaccinated were also more likely to abort than cows that were not on community pastures regardless of vaccination status. Adverse calving-associated events such as severe dystocia, problems such as uterine prolapse or retained placentas, abortion or calf death within 1 hour of birth were also associated with an increased risk of abortion the subsequent calving season after accounting for all other factors. PMID:24472651

Waldner, C L

2014-04-01

336

Identifying and managing cow's milk protein allergy  

Microsoft Academic Search

Cow's milk protein (CMP) is usually one of the first complementary foods to be introduced into the infant's diet and is commonly consumed throughout childhood as part of a balanced diet. CMP is capable of inducing a multitude of adverse reactions in children, which may involve organs like the skin, gastrointestinal (GI) tract or respiratory system. The diagnosis of CMP-induced

George du Toit; Rosan Meyer; Neil Shah; Ralf G Heine; Michael A Thomson; Gideon Lack; Adam T Fox

2010-01-01

337

FEEDING DAIRY COWS TO MINIMIZE NITROGEN EXCRETION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Dairy cows utilize feed crude protein (CP; N x 6.25) much greater efficiently than other ruminant livestock but still excrete about 2-3 times more N in manure than in milk. This contributes to increased costs of milk production costs and to environmental N pollution. The function of dietary CP is ...

338

Outbreaks of bacterial pneumonia in dairy cows.  

PubMed

• Mannheimia haemolytica causes respiratory disease and deaths in housed adult dairy cows • Congenital sarcoma in a neonatal Hereford calf • Unusual presentation of pregnancy toxaemia in housed ewes • Gastrointestinal parasitism in goats associated with suspected treatment failure These are among matters discussed in the disease surveillance report for February from SAC Consulting: Veterinary Services (SAC C VS). PMID:24832886

2014-05-17

339

Thermoregulatory responses of Holstein and Brown Swiss heat-stressed dairy cows to two different cooling systems.  

PubMed

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. PMID:14624352

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

2004-02-01

340

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

NASA Astrophysics Data System (ADS)

. 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.

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

341

The influence of different factors on selenium levels in dairy cow herds in the central-eastern region of Poland.  

PubMed

Selenium has been recognised as a basic bioelement that determines normal development and health of animals and humans alike. Studies of many authors revealed the influence of selenium deficiency on immunity, health, reproduction and production of dairy cows. Selenium deficiency have been reported in a number of countries, for example in different regions of Poland. The aim of the study was to determine the Se levels in blood serum of dairy cows in the Lublin region. In the periods: autumn 2003, winter 2003 and autumn 2004 selenium concentrations were investigated in serum samples from 180 dairy cows. The samples were obtained from 11 farms. The selenium concentrations were estimated with the ASA method. The monitoring studies have found that Se serum levels are dependent on season of the year, physiological period, maintenance systems and methods of feeding. Mean selenium serum levels observed in the study were between 0.21-0.92 micromol/l, especially (micromol/l): lactation 0.74 +/- 0.13, drying-off period 0.67 +/- 0.15, autumn 2003 0.38 +/- 0.17, winter 2003 0.48 +/- 0.16, autumn 2004 0.69 +/- 0.18. These results suggest that selenium should be supplemented, especially in high-producing dairy cow herds. PMID:16180584

Stec, A; Mochol, J; Kurek, L; Wa?kuska, G; Cha?abis-Mazurek, A

2005-01-01

342

Influence of Trueperella pyogenes in uterus on corpus luteum lifespan in cycling cows.  

PubMed

To study ovarian responses to long-term intrauterine infusions of Trueperella pyogenes (T. pyogenes), 12 nonlacting Holstein cows were transcervically infused with 10 mL of a bacterial solution (8-19 × 10(8) colony-forming units/mL), and the uteri of another four cows (control) were similarly infused with sterile physiological saline. Infusions were done six times, every 3 days from Days 3 to 18 (Day 0 = day of spontaneous ovulation). Development of ovarian follicles and the CL were monitored with transrectal, real-time ultrasonography. In five of the experimentally infected cows (group A), the CL, which developed after Day 0, regressed without maturing, and the first dominant follicle (DF) ovulated (mean ± SEM interovulatory interval, 8.6 ± 0.5 days). In group A, plasma 13,14-dihydro-15-keto-PGF(2?) (PGFM) concentrations rose sharply on Day 6, but plasma progesterone concentrations did not increase substantially (as in the control) and were maintained at approximately 2.5 ng/mL after the first DF ovulated. In seven of the 12 infected cows (group B), the developing CL which formed after Day 0 matured and the second DF ovulated. However, the CL lifespan was shorter (P < 0.01) and the second DF ovulated earlier than in control (interovulatory interval, 16.0 ± 0.4 days and 22.3 ± 1.9 days; P < 0.01). Although there was no sharp increase in PGFM in group B, it tended to be high between Days 11 and 18. In conclusion, long-term, intrauterine infusions of T. pyogenes caused the CL to regress prematurely or to have a somewhat shorter lifespan because of release of endogenous PGF(2?). PMID:23312720

Kaneko, Kazuyuki; Nakamura, Makoto; Sato, Reiichiro

2013-03-15

343

Why are dairy cows not able to cope with the subacute ruminal acidosis?  

PubMed

One of the largest challenges for the dairy industry is to provide cows with a diet which is highly energetic but does not negatively affect their rumens' functions. In highly productive dairy cows, feeding diets rich in readily fermentable carbohydrates provides energy precursors needed for maximum milk production, but simultaneously decreases ruminal pH, leading to a widespread prevalence of subacute ruminal acidosis. Maximizing milk production without triggering rumen acidosis still challenges dairy farmers, who try to prevent prolonged bouts of low ruminal pH mainly by proper nutrition and management practices. The animals try to avoid overeating fermentable feeds, as it causes negative consequences by disturbing digestive processes. The results of several experiments show that ruminants, including sheep and beef cattle, are able to modify some aspects of feeding behaviour in order to adjust nutrient intake to their needs and simultaneously prevent physiological disturbances. Particularly, such changes (e.g., increased preference for fibrous feeds, reduced intake of concentrates) were observed in animals, which were trying to prevent the excessive drop of rumen fluid pH. Thanks to a specific mechanism called "the postingestive feedback", animals should be able to work out such a balance in intake, so they do not suffer either from hunger or from negative effects of over-ingesting the fermentable carbohydrates. This way, an acidosis should not be a frequent problem in ruminants. However, prolonged periods of excessively decreased rumen pH are still a concern in dairy cows. It raises a question, why the regulation of feed intake by postingestive feedback does not help to maintain stable rumen environment in dairy cows? PMID:24597322

Brzozowska, A M; Sloniewski, K; Oprzadek, J; Sobiech, P; Kowalski, Z M

2013-01-01

344

The effects of feeding 3-nitrooxypropanol on methane emissions and productivity of Holstein cows in mid lactation.  

PubMed

The objective of the current study was to determine the effects of adding 3-nitrooxypropanol to the diet of lactating Holstein cows on methane emissions, rumen fermentation, ruminal microbial profile, and milk production. Twelve ruminally cannulated Holstein cows in midlactation were used in a crossover design study with 28-d periods. Cows were fed a diet containing 38% forage on a dry matter basis with either 2,500 mg/d of 3-nitrooxypropanol (fed as 25 g of 10% 3-nitrooxypropanol on silicon dioxide) or 25 g/d of silicon dioxide (control). After a 21-d diet adaptation period, dry matter intake (DMI) and milk yield were recorded daily. Rumen fluid and digesta were collected on d 22 and 28 for volatile fatty acid analysis and microbial profiling. Enteric methane emissions were measured on d 23 to 27 using the sulfur hexafluoride tracer gas technique. Feeding 3-nitrooxypropanol did not affect DMI; however, methane production was reduced from 17.8 to 7.18 g/kg of DMI. No change in milk or milk component yields was observed, but cows fed 3-nitrooxypropanol gained more body weight than control cows (1.06 vs. 0.39 kg/d). Concentrations of total volatile fatty acids in ruminal fluid were not affected by treatment, but a reduction in acetate proportion and a tendency for an increase in propionate proportion was noted. As such, a reduction in the acetate-to-propionate ratio was observed (2.02 vs. 2.36). Protozoa counts were not affected by treatment; however, a reduction in methanogen copy count number was observed when 3-nitrooxypropanol was fed (0.95 vs. 2.69 × 10(8)/g of rumen digesta). The data showed that feeding 3-nitrooxypropanol to lactating dairy cows at 2,500 mg/d can reduce methane emissions without compromising DMI or milk production. PMID:24630651

Haisan, J; Sun, Y; Guan, L L; Beauchemin, K A; Iwaasa, A; Duval, S; Barreda, D R; Oba, M

2014-05-01

345

Chewing over physiology integration.  

PubMed

An important challenge for both students and teachers of physiology is to integrate the different areas in which physiological knowledge is didactically divided. In developing countries, such an issue is even more demanding, because budget restrictions often affect the physiology program with laboratory classes being the first on the list when it comes to cuts in expenses. With the aim of addressing this kind of problem, the graduate students of our department organized a physiology summer course offered to undergraduate students. The objective was to present the different physiological systems in an integrated fashion. The strategy pursued was to plan laboratory classes whose experimental results were the basis for the relevant theoretical discussions. The subject we developed to illustrate physiology integration was the study of factors influencing salivary secretion. PMID:15718383

Abdulkader, Fernando; Azevedo-Martins, Anna Karenina; Miranda, Manoel de Arcisio; Brunaldi, Kellen

2005-03-01

346

Variation in fat mobilization during early lactation differently affects feed intake, body condition, and lipid and glucose metabolism in high-yielding dairy cows.  

PubMed

Fat mobilization to meet energy requirements during early lactation is inevitable because of insufficient feed intake, but differs greatly among high-yielding dairy cows. Therefore, we studied milk production, feed intake, and body condition as well as metabolic and endocrine changes in high-yielding dairy cows to identify variable strategies in metabolic and endocrine adaptation to overcome postpartum metabolic load attributable to milk production. Cows used in this study varied in fat mobilization around calving, as classified by mean total liver fat concentrations (LFC) postpartum. German Holstein cows (n=27) were studied from dry off until d 63 postpartum in their third lactation. All cows were fed the same total mixed rations ad libitum during the dry period and lactation. Plasma concentrations of metabolites and hormones were measured in blood samples taken at d 56, 28, 15, and 5 before expected calving and at d 1 and once weekly up to d 63 postpartum. Liver biopsies were taken on d 56 and 15 before calving, and on d 1, 14, 28, and 49 postpartum to measure LFC and glycogen concentrations. Cows were grouped accordingly to mean total LFC on d 1, 14, and 28 in high, medium, and low fat-mobilizing cows. Mean LFC (±SEM) differed among groups and were 351±14, 250±10, and 159±9 mg/g of dry matter for high, medium, and low fat-mobilizing cows, respectively, whereas hepatic glycogen concentrations postpartum were the highest in low fat-mobilizing cows. Cows in the low group showed the highest dry matter intake and the least negative energy balance postpartum, but energy-corrected milk yield was similar among groups. The decrease in body weight postpartum was greatest in high fat-mobilizing cows, but the decrease in backfat thickness was greatest in medium fat-mobilizing cows. Plasma concentrations of nonesterified fatty acids and ?-hydroxybutyrate were highest around calving in high fat-mobilizing cows. Plasma triglycerides were highest in the medium group and plasma cholesterol concentrations were lowest in the high group at calving. During early lactation, the decrease in plasma glucose concentrations was greatest in the high group, and plasma insulin concentrations postpartum were highest in the low group. The revised quantitative insulin sensitivity check index values decreased during the transition period and postpartum, and were highest in the medium group. Plasma cortisol concentrations during the transition period and postpartum period and plasma leptin concentrations were highest in the medium group. In conclusion, cows adapted differently to the metabolic load and used variable strategies for homeorhetic regulation of milk production. Differences in fat mobilization were part of these strategies and contributed to the individual adaptation of energy metabolism to milk production. PMID:23127904

Weber, C; Hametner, C; Tuchscherer, A; Losand, B; Kanitz, E; Otten, W; Singh, S P; Bruckmaier, R M; Becker, F; Kanitz, W; Hammon, H M

2013-01-01

347

Starch levels on performance, milk composition and energy balance of lactating dairy cows.  

PubMed

The objective of this experiment was to evaluate the effects of starch levels in diets with the replacement of citrus pulp for corn on milk yield, milk composition, and energy balance of lactating dairy cows. Twenty-eight multiparous Holstein cows were used in seven 4?×?4 Latin squares conducted concurrently, and each experimental period consisted of 20 days (16 days for adaptation and 4 days for sampling). The experimental treatments comprised four starch levels: 15, 20, 25, and 30% in the diet. The dry matter intake increased linearly with increasing starch levels. The milk yield and 3.5% fat-corrected milk yield showed quadratic response to increasing starch levels. The milk protein content and milk total solids content responded linearly to increasing starch levels. The feed efficiency, milk lactose content, milk urea nitrogen, plasma urea nitrogen, and plasma glucose concentration were not affected by starch levels. The estimated net energy for lactation (NEL) intake increased linearly as the starch level was raised. Although the milk NEL output per kilogram of milk was not affected by starch, the milk NEL output daily responded quadratically to starch levels. In addition, the NEL in body weight gain also responded quadratically to increasing starch levels. The efficiency of energy use for milk yield and the NEL efficiency for production also responded quadratically to increasing starch levels. Diets for mid-lactating dairy cows producing around 30 kg/day of milk should be formulated to provide around 25% starch to optimize performance. PMID:25315370

Carmo, Carolina Almeida; Batistel, Fernanda; de Souza, Jonas; Martinez, Junio Cesar; Correa, Paulo; Pedroso, Alexandre Mendonça; Santos, Flávio Augusto Portela

2015-01-01

348

Lying behavior and postpartum health status in grazing dairy cows.  

PubMed

Many cows have difficulty making the transition from pregnancy to lactation, as evidenced by the high incidence of disease that occurs in the weeks after calving. Changes in lying behavior can be used as an indicator of illness, yet no work to date has evaluated this relationship in dairy cows on pasture. The objectives of this study were to describe the lying behavior of grazing dairy cows during the first 3 wk after calving and determine the relationships between transition diseases and lying behavior. Our convenience sample included 227 multiparous and 47 primiparous Holstein cows from 6 commercial farms. Cows were recruited as they calved during the spring calving period. Electronic data loggers (Hobo Pendant G Acceleration, Onset Computer Corp., Pocasset, MA) recorded lying behavior at 1-min intervals. Diseases were recorded up to 21 d in milk, and cows were subsequently categorized into 3 health categories: (1) healthy, not lame and had no other signs of clinical (retained placenta, milk fever, metritis, mastitis) or subclinical (ketosis, hypocalcemia) postpartum diseases; (2) lame, identified as being clinically or severely lame with no other signs of clinical or subclinical postpartum disease; and (3) sick, diagnosed as having one or more clinical postpartum diseases (with or without a subclinical disease) but not lame. This last group was further divided into 2 groups: those that were diagnosed with a single clinical health event and those diagnosed with more than one clinical event. Lying behavior differed between primiparous and multiparous cows; primiparous cows divided their lying time into more bouts than did multiparous cows (9.7 ± 0.54 vs. 8.4 ± 0.26 bouts/d) and spent less time lying down than multiparous cows (7.5 ± 0.38 h/d vs. 8.5 ± 0.19 h/d). Lying behavior was also affected by illness; primiparous cows that developed more than one clinical disease, excluding lameness, spent more time lying, and tended to have longer lying bouts in the days following calving compared with healthy cows; multiparous severely lame cows spent more time lying down (1.7 h longer per day) compared with multiparous cows that were nonlame. Clinically lame cows had fewer lying bouts per day and these bouts were of longer duration than healthy nonlame cows. In summary, changes in lying behavior after calving were associated with postpartum health status in grazing dairy cows. PMID:25151885

Sepúlveda-Varas, P; Weary, D M; von Keyserlingk, M A G

2014-10-01

349

Effects of cow diet on the microbial community and organic matter and nitrogen content of feces.  

PubMed

Knowledge of the effects of cow diet on manure composition is required to improve nutrient use efficiency and to decrease emissions of N to the environment. Therefore, we performed an experiment with nonlactating cows to determine the consequences of changes in cow rations for the chemical characteristics and the traits of the microbial community in the feces. In this experiment, 16 cows were fed 8 diets, differing in crude protein, neutral detergent fiber, starch, and net energy content. These differences were achieved by changing dietary ingredients or roughage to concentrate ratio. After an adaptation period of 3 wk, fecal material was collected and analyzed. Observed results were compared with simulated values using a mechanistic model that provides insight into the mechanisms involved in the effect of dietary variation on fecal composition. Feces produced on a high-fiber, low-protein diet had a high C:N ratio (>16) and had lower concentrations of both organic and inorganic N than feces on a low-fiber, high-protein diet. Fecal bacterial biomass concentration was highest in high-protein, high-energy diets. The fraction of inorganic N in the feces was not significantly different between the different feces. Microbial biomass in the feces ranged from 1,200 to 8,000 microg of C/g of dry matter (average: 3,700 microg of C/g of dry matter). Bacterial diversity was similar for all fecal materials, but the different protein levels in the feeding regimens induced changes in the community structure present in the different feces. The simulated total N content (N(total)) in the feces ranged from 1.0 to 1.5 times the observed concentrations, whereas the simulated C:N(total) of the feces ranged from 0.7 to 0.9 times the observed C:N(total). However, bacterial biomass C was not predicted satisfactorily (simulated values being on average 3 times higher than observed), giving rise to further discussion on the definition of microbial C in feces. Based on these observations, it was concluded that diet composition affected fecal chemical composition and microbial biomass. These changes may affect the nutrient use and efficiency of the manure. Because the present experiment used a limited number of dry cows and extreme diet regimens, extrapolation of results to other dairy cow situations should be done with care. PMID:17954755

van Vliet, P C J; Reijs, J W; Bloem, J; Dijkstra, J; de Goede, R G M

2007-11-01

350

Adaptable and Adaptive Hypermedia  

E-print Network

yields countless benefits for both users and businesses. Adaptable and Adaptive Hypermedia Systems examines both types of new hypermedia systems; discussing the benefits, im- pacts and implications of both ___________________________________ E-Mail ________________________________ ORDER FORM IDEA GROUP INC. 701 E. Chocolate Avenue, Suite

Magoulas, George D.

351

Clinicopathological evaluation of downer dairy cows with fatty liver  

PubMed Central

This study evaluated the relationship between severity of fatty liver and macromineral status in downer dairy cows and determined the usefulness of selected biochemical analytes for assessing prognosis. Blood and liver biopsy specimens were obtained from 36 Holstein downer cows shortly after the cows became recumbent and before they were treated. Liver tissue was examined histologically and serum activity of liver-derived enzymes and concentration of total lipids, triglycerides, bile acids, glucose, ?-hydroxybutyrate, acetoacetic acid, total bilirubin, non-esterified fatty acids (NEFA), cholesterol and macrominerals (Ca, Mg, K, Na, P) were determined. Fatty liver infiltration was severe in 44% of the cows and moderate in 44%. Serum activities of ornithine carbamoyltransferase and glutamate dehydrogenase, and NEFA/cholesterol ratio were good indicators of fatty liver. Cows with severe fatty liver had the lowest mean K values. The prognosis is guarded for downer cows with moderate and severe fatty liver and when total bilirubin concentration is high. PMID:20808573

Kalaitzakis, Emmanouil; Panousis, Nikolaos; Roubies, Nikolaos; Giadinis, Nektarios; Kaldrymidou, Eleni; Georgiadis, Marios; Karatzias, Harilaos

2010-01-01

352

Periparturient concentrations of insulin glucagon and ketone bodies in dairy cows fed two different levels of nutrition and varying concentrate/roughage ratios.  

PubMed

High producing multiparous dairy cows were fed either diets differing in energy content or diets with identical energy and protein content but differing in roughage content at the end of the dry period and beginning of lactation. Basal insulin and ketone bodies were analysed every week from 3 weeks before to 7 weeks after calving. Pancreatic glucagon was estimated 3 weeks before, 1-3 days after, and 3 weeks after calving. Before calving the feeding regimen had a very strong influence on the basal insulin level. High amounts of concentrate increased basal insulin levels until one week before calving and caused an interruption in the physiological decreasing course. After calving the insulin levels were low in all groups of cows. Before calving there were small variations in the glucagon levels, and no influence of feeding was observed. After calving there was a strong increase, especially in the cows fed the highest amounts of concentrate. Feeding high amounts of concentrate resulted in varying and in many cases increased levels of ketone bodies in plasma. Hyperketonemic cows had lower insulin and higher glucagon levels than normal cows. The influence of non-structural carbohydrates in the feed on pancreatic hormones is a cause of ketogenesis is discussed. PMID:8480460

Holtenius, P; Olsson, G; Björkman, C

1993-03-01

353

Late gestation supplementation of beef cows differing in body condition score: effects on cow and calf performance.  

PubMed

A 2-yr study utilizing 120 mature, crossbred (Angus × Herford) cows/year, evaluated the influence of cow BCS and dried distillers grains with solubles (DDGS) supplementation during late gestation on cow performance and productivity of subsequent offspring. Treatments were arranged as a 2×2 factorial in a randomized complete block design with 2 BCS and with or without DDGS supplementation. Cows were nutritionally managed to enter the last trimester of gestation with a BCS of approximately 4 (LBCS) or 6 (HBCS) and were thereafter managed in a single herd (initial BCS were 4.4 and 5.7 for LBCS and HBCS treatments, respectively). During the last trimester, 12.7 kg/cow of low quality meadow hay (6.4% CP; DM basis) was provided each day. Supplemented cows were gathered and sorted into pens (12 pens; 5 cows/pen; 6 pens/BCS) every Monday, Wednesday, and Friday, and received the equivalent of 0.9 kg/cow daily of DDGS (31% CP; DM basis; supplement was consumed within 30 min on each supplementation day). Calf birth weight was greater for HBCS compared to LBCS (P=0.001) and for supplemented compared to nonsupplemented cows (P=0.04). Cow weight at weaning was greater for HBCS compared with LBCS (P<0.001); however, no differences were noted because of supplementation (P=0.16). Weaning weight was greater for the offspring of supplemented compared to nonsupplemented cows (P=0.02). There were no differences in postweaning calf performance (growing lot and feedlot) or carcass characteristics (P>0.05) due to treatments. Nevertheless, HBCS cows had approximately 10% more live calves at birth and at weaning (P?0.01) compared to LBCS cows. Consequently, the total weaned calf weight per cow was 26 kg greater for HBCS compared with LBCS (P=0.004). Pregnancy rate was greater (P=0.05) for HBCS than LBCS cows (92% vs. 79%, respectively) but not affected by supplementation (P=0.94). This research demonstrates the potential consequences of not maintaining cows in adequate BCS at calving. Also, though it appears that supplementation of beef cows with DDGS during late gestation has a positive effect on weaning weight, there was no apparent developmental programming effect on feedlot performance and carcass characteristics of calves. PMID:23989877

Bohnert, D W; Stalker, L A; Mills, R R; Nyman, A; Falck, S J; Cooke, R F

2013-11-01

354

Production response of lactating cows fed dried versus wet brewers' grain in diets with similar dry matter content.  

PubMed

Twenty-four Holstein-Friesian dairy cows (20 intact and 4 fitted with rumen cannula) during early lactation (56 +/- 25.3 d in milk) were assigned to two treatments to determine intake and production responses to feeding dried and wet brewers' grain. There were two cows fitted with a rumen cannula in each treatment. Cows were fed a total mixed ration twice daily containing either dried or wet brewers' grain at 15% of the dietary dry matter (DM). The diet contained 47% forage and 53% concentrate. The experimental design was a replicated 2 x 2 Latin square with two periods of 5 wk each. First 2 wk in each period were considered as adaptation to diets and data from the last 3 wk were used for treatment comparisons. Dried and wet brewers' diets contained 68.0 and 66.5% DM, respectively. Feeding brewers' grain dry or wet to dairy cows had no influence on feed intake (25.6 vs. 25.1 kg/d), fat corrected milk yield (40.1 vs. 40.7 kg/d), milk composition and feed consumption. The pH, ammonia, total volatile fatty acids and molar ratios of volatile fatty acids in the rumen fluid were not different between treatments. Fatty acid composition of milk fat from cows fed diets containing dry or wet brewers' grain was identical, except C18:2 and C18:3 fatty acids were lower in milk fat from cows fed wet brewers' grain compared with dried brewers' grain. The results from the present study suggest that the performance of cows fed either dried or wet brewers' grain at 15% of dietary DM was similar when diets had the same DM. The average price for dried and wet brewers' grain in the United States from July 2001 to June 2002 was dollars 145.3 and dollars 96.9/metric tonne DM, respectively. Using wet instead of dried brewers' grain will save dollars 49/metric tonne minus the difference in storage costs. Wet brewers' grain can be fed to dairy cows in areas that are close to the brewery and provides nutritive value similar to the dried brewers' grain. PMID:14507027

Dhiman, T R; Bingham, H R; Radloff, H D

2003-09-01

355

Negative energy balance increases periprandial ghrelin and growth hormone concentrations in lactating dairy cows.  

PubMed

The reported effects of feeding on growth hormone (GH) secretion in ruminants have been inconsistent, and are likely influenced by energy status of animals. High-producing dairy cows in early lactation and late lactation were used to assess the effects of energy balance on temporal variation of plasma metabolites and hormones. Cows were fed a single diet once daily, and feed was withdrawn for 90 min prior to feeding. Beginning at the time of feed withdrawal, plasma samples were collected via jugular catheters hourly for 24h. Concentrations of non-esterified fatty acids and GH were measured for all samples, while insulin, glucose, and acylated (active) ghrelin were quantified for four sample times around feeding. As expected, calculated energy balance was significantly lower in early lactation than late lactation cows (-43.5 MJ retained/day versus 7.2 MJ retained/day). Following the primary meal of the day, a GH surge was observed in early lactation but not in late lactation cows. This difference was not explained by temporal patterns in non-esterified fatty acid, insulin, or glucose concentrations. However, a preprandial ghrelin surge was observed in early lactation only, suggesting that ghrelin was responsible for the prandial GH surge in this group. Results of a stepwise regression statistical analysis showed that both preprandial ghrelin concentration and energy balance were significant predictors of prandial GH increase over baseline. Adaptations to negative energy balance in lactating dairy cattle likely include enhanced ghrelin secretion and greater GH response to ghrelin. PMID:17467225

Bradford, Barry J; Allen, Michael S

2008-02-01

356

Diet-Induced Alterations in Total and Metabolically Active Microbes within the Rumen of Dairy Cows  

PubMed Central

DNA-based techniques are widely used to study microbial populations; however, this approach is not specific to active microbes, because DNA may originate from inactive and/or dead cells. Using cDNA and DNA, respectively, we aimed to discriminate the active microbes from the total microbial community within the rumen of dairy cows fed diets with increasing proportions of corn silage (CS). Nine multiparous lactating Holstein cows fitted with ruminal cannulas were used in a replicated 3×3 Latin square (32-d period; 21-d adaptation) design to investigate diet-induced shifts in microbial populations by targeting the rDNA gene. Cows were fed a total mixed ration with the forage portion being either barley silage (0% CS), a 50?50 mixture of barley silage and corn silage (50% CS), or corn silage (100% CS). No differences were found for total microbes analyzed by quantitative PCR, but changes were observed within the active ones. Feeding more CS to dairy cows was accompanied by an increase in Prevotella rRNA transcripts (P?=?0.10) and a decrease in the protozoal rRNA transcripts (P<0.05). Although they were distributed differently among diets, 78% of the amplicons detected in DNA- and cDNA-based fingerprints were common to total and active bacterial communities. These may represent a bacterial core of abundant and active cells that drive the fermentation processes. In contrast, 10% of amplicons were specific to total bacteria and may represent inactive or dead cells, whereas 12% were only found within the active bacterial community and may constitute slow-growing bacteria with high metabolic activity. It appears that cDNA-based analysis is more discriminative to identify diet-induced shifts within the microbial community. This approach allows the detection of diet-induced changes in the microbial populations as well as particular bacterial amplicons that remained undetected using DNA-based methods. PMID:23593365

Lettat, Abderzak; Benchaar, Chaouki

2013-01-01

357

Interacting with human physiology  

Microsoft Academic Search

We propose a novel system that incorporates physiological monitoring as part of the human–computer interface. The sensing element is a thermal camera that is employed as a computer peripheral. Through bioheat modeling of facial imagery almost the full range of vital signs can be extracted, including localize blood flow, cardiac pulse, and breath rate. This physiological information can then be

Ioannis Pavlidis; Jonathan Dowdall; Nanfei Sun; Colin Puri; Jin Fei; Marc Garbey

2007-01-01

358

Microbial physiology vol. 29  

SciTech Connect

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.

Rose, A.H. (School of Biological Sciences, Bath Univ. (GB)); Tempest, D.W. (Dept. of Microbiology Univ. of Sheffield (GB))

1988-01-01

359

Phun Week: Understanding Physiology  

ERIC Educational Resources Information Center

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…

Limson, Mel; Matyas, Marsha Lakes

2009-01-01

360

Insect Physiology Online  

NSDL National Science Digital Library

A large database dedicated to research articles about various topics of insect physiology. Topics range from excretion to diapause to temperature and water regulation. There are also extensive listings of resources (academic units, funding, journals) and course data on insect physiology.

0000-00-00

361

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...

362

SREBPs: Metabolic Integrators in Physiology and Metabolism  

PubMed Central

Recent advances have significantly increased our understanding of how sterol regulatory element binding proteins (SREBPs) are regulated at the transcriptional and post-transcriptional levels in response to cellular signaling. The phosphatidyl inositol-3-kinase (PI3K) and SREBP pathways intersect at multiple points and recent insights demonstrate the importance of tight regulation of the PI3K pathway for regulating SREBPs in the adaptation to fluctuating dietary calorie load in the mammalian liver. Additionally, genetic and genome-wide approaches highlight new functions for SREBPs in connecting lipid metabolism with other cellular processes where lipid pathway flux affects physiologic or pathophysiologic adaptation, such as cancer, steatosis and innate immunity. This review focuses on recent advances and new roles for mammalian SREBPs in physiology and metabolism. PMID:22154484

Jeon, Tae-Il; Osborne, Timothy F.

2011-01-01

363

Maxillary osteosarcoma in a beef suckler cow  

PubMed Central

A ten-year-old beef suckler cow was referred to the Scottish Centre for Production Animal Health & Food Safety of the University of Glasgow, because of facial swelling in the region of the right maxilla. The facial swelling was first noticed three months earlier and was caused by a slow growing oral mass which contained displaced, loosely embedded teeth. The radiographic, laboratory and clinicopathological findings are described. Necropsy, gross pathology and histological findings confirmed the mass as a maxillary osteosarcoma. PMID:22788782

2012-01-01

364

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

ERIC Educational Resources Information Center

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)

Eiswirth, Marcus; And Others

1982-01-01

365

Intraperitoneal insemination in repeat-breeder cows: a preliminary report.  

PubMed

Intraperitoneal insemination of 62 repeat-breeder dairy cows resulted in 9 pregnancies. The pregnancy rate was not different for intraperitoneal or uterine inseminations. In nonpregnant cows, reproductive variables such as the percentage of cows returning to estrus, the average interval from insemination to the next estrus, and the pregnancy rate following subsequent uterine insemination were not influenced by intraperitoneal insemination. Our results suggest that intraperitoneal insemination could be an alternative procedure to the usual deposition of semen into the uterus in repeat breeder cows. PMID:16727714

López-Gatius, F

1995-07-15

366

Mature Runt Cow Lumbar Intradiscal Pressures And Motion Segment Biomechanics  

PubMed Central

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

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

2009-01-01

367

Environmental stressors influencing hormones and systems physiology in cattle  

PubMed Central

Environmental stressors undoubtedly influence organismal biology, specifically the endocrine system that, in turn, impact cattle at the systems physiology level. Despite the significant advances in understanding the genetic determinants of the ideal dairy or beef cow, there is a grave lack of understanding of the systems physiology and effects of the environmental stressors that interfere with the endocrine system. This is a major problem because the lack of such knowledge is preventing advances in understanding gene-environment interactions and developing science-based solutions to these challenges. In this review, we synthesize the current knowledge on the nature of the major environmental stressors, such as climate (heat, cold, wind, and humidity), nutrition (feeds, feeding systems, and endocrine disruptors) and management (housing density and conditions, transportation, weaning practices). We summarize the impact of each one of these factors on cattle at the systems level, and provide solutions for the challenges. PMID:24996419

2014-01-01

368

Current Topics for Teaching Skeletal Muscle Physiology  

NSDL National Science Digital Library

Contractions of skeletal muscles provide the stability and power for all body movements. Consequently, any impairment in skeletal muscle function results in some degree of instability or immobility. Factors that influence skeletal muscle structure and function are therefore of great interest both scientifically and clinically. Injury, disease, and old age are among the factors that commonly contribute to impairment in skeletal muscle function. The goal of this article is to update current concepts of skeletal muscle physiology. Particular emphasis is placed on mechanisms of injury, repair, and adaptation in skeletal muscle as well as mechanisms underlying the declining skeletal muscle structure and function associated with aging. For additional materials please refer to the "Skeletal Muscle Physiology" presentation located on the American Physiological Society Archive of Teaching Resources Web site (http://www.apsarchive.org).

Susan V. Brooks (University of Michigan)

2003-12-01

369

Physiologic complexity and aging: implications for physical function and rehabilitation.  

PubMed

The dynamics of most healthy physiological processes are complex, in that they are comprised of fluctuations with information-rich structure correlated over multiple temporospatial scales. Lipsitz and Goldberger (1992) first proposed that the aging process may be characterized by a progressive loss of physiologic complexity. We contend that this loss of complexity results in functional decline of the organism by diminishing the range of available, adaptive responses to the innumerable stressors of everyday life. From this relationship, it follows that rehabilitative interventions may be optimized by targeting the complex dynamics of human physiology, and by quantifying their effects using tools derived from complex systems theory. Here, we first discuss several caveats that one must consider when examining the functional and rehabilitative implications of physiologic complexity. We then review available evidence regarding the relationship between physiologic complexity and system functionality, as well as the potential for interventions to restore the complex dynamics that characterize healthy physiological function. PMID:22985940

Manor, Brad; Lipsitz, Lewis A

2013-08-01

370

Space physiology and medicine (2nd edition)  

NASA Technical Reports Server (NTRS)

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.

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

1989-01-01

371

Physiologic and pharmacokinetic changes in pregnancy.  

PubMed

Physiologic changes in pregnancy induce profound alterations to the pharmacokinetic properties of many medications. These changes affect distribution, absorption, metabolism, and excretion of drugs, and thus may impact their pharmacodynamic properties during pregnancy. Pregnant women undergo several adaptations in many organ systems. Some adaptations are secondary to hormonal changes in pregnancy, while others occur to support the gravid woman and her developing fetus. Some of the changes in maternal physiology during pregnancy include, for example, increased maternal fat and total body water, decreased plasma protein concentrations, especially albumin, increased maternal blood volume, cardiac output, and blood flow to the kidneys and uteroplacental unit, and decreased blood pressure. The maternal blood volume expansion occurs at a larger proportion than the increase in red blood cell mass, which results in physiologic anemia and hemodilution. Other physiologic changes include increased tidal volume, partially compensated respiratory alkalosis, delayed gastric emptying and gastrointestinal motility, and altered activity of hepatic drug metabolizing enzymes. Understating these changes and their profound impact on the pharmacokinetic properties of drugs in pregnancy is essential to optimize maternal and fetal health. PMID:24772083

Costantine, Maged M

2014-01-01

372

Physiologic and pharmacokinetic changes in pregnancy  

PubMed Central

Physiologic changes in pregnancy induce profound alterations to the pharmacokinetic properties of many medications. These changes affect distribution, absorption, metabolism, and excretion of drugs, and thus may impact their pharmacodynamic properties during pregnancy. Pregnant women undergo several adaptations in many organ systems. Some adaptations are secondary to hormonal changes in pregnancy, while others occur to support the gravid woman and her developing fetus. Some of the changes in maternal physiology during pregnancy include, for example, increased maternal fat and total body water, decreased plasma protein concentrations, especially albumin, increased maternal blood volume, cardiac output, and blood flow to the kidneys and uteroplacental unit, and decreased blood pressure. The maternal blood volume expansion occurs at a larger proportion than the increase in red blood cell mass, which results in physiologic anemia and hemodilution. Other physiologic changes include increased tidal volume, partially compensated respiratory alkalosis, delayed gastric emptying and gastrointestinal motility, and altered activity of hepatic drug metabolizing enzymes. Understating these changes and their profound impact on the pharmacokinetic properties of drugs in pregnancy is essential to optimize maternal and fetal health. PMID:24772083

Costantine, Maged M.

2014-01-01

373

Genetics and the physiological ecology of conifers  

SciTech Connect

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.

Mitton, J.B.

1995-07-01

374

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

PubMed

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

Kmicikewycz, A D; Heinrichs, A J

2015-01-01

375

Partitioning of energy during lactation of primiparous beef cows.  

PubMed

For a beef cow to continue in an annual production cycle, she must rebreed within 3 mo after calving. Malnutrition during this period frequently results in failure of the cow to become pregnant. The energetic needs of the cow are increased by lactation, and additional energy is required for growth of the primiparous cow. Determining energy expenditures during the first 40 to 60 d postpartum is critical to developing feed programs that will allow cows to become pregnant with a second calf. Sixty-seven balance trials were conducted on 25 MARC III cows (4-breed composite: (1/4) Hereford, (1/4) Angus, (1/4) Red Poll, and (1/4) Pinzgauer) that were between 3 and 53 d in milk. Cows' BW were 481 +/- 4 kg. Metabolizable energy intake ranged from 14.8 to 28.9 Mcal/d. Milk yields ranged from 4.7 to 13.3 kg/d. Recovered energy (RE) increased linearly with increased ME intake. Forty-seven observations were obtained with cows in negative tissue energy (TE) balance, and 20 observations were obtained with cows in positive TE balance. Estimated zero RE from regression analysis of RE on ME intake was 146 kcal of ME/kg of BW(0.75). Efficiency of conversion of ME to lactation energy (LE) was 72%. The efficiency for conversion of ME to TE and the conversion of TE to LE was 78%. Our findings suggest that, even though their milk production is lower, the overall efficiency of energy retention in young beef cows is similar to that of dairy cows. PMID:16864877

Freetly, H C; Nienaber, J A; Brown-Brandl, T

2006-08-01

376

Short communication: Born to be a loser cow?  

PubMed

Over the last few years, an increasing awareness has arisen in Denmark of the existence of cows with a generally lowered health and production status, referred to as "loser cows." A previous study has estimated that the overall prevalence of loser cows in Danish Holstein herds is 3.2%. The aim of this study was to estimate genetic and phenotypic parameters for the loser cow state and the underlying traits: lameness, hock lesions, other cutaneous lesions, and condition of hair coat. Records on 6,098 cows were analyzed with an animal model including fixed effects of herd, season of scoring and location of scoring, age at first calving, lactation stage, and parity in addition to additive genetic effects and permanent environmental effects. The heritability of the loser cow score was 0.08 and for the underlying traits the heritability ranged from 0.05 to 0.12. The genetic correlations between various pairs of traits included in the loser cow score ranged from 0.04 to 0.68 and the phenotypic correlations ranged from 0.09 to 0.21. The genetic and phenotypic correlations between the loser cow score and the underlying traits ranged from 0.25 to 0.89 and 0.20 to 0.85, respectively, supporting the concept of the loser cow score. The traits included in the loser cow score are easy to assess and all showed genetic variation. They are therefore suitable for inclusion in a total merit index aimed at breeding for more robust cows. PMID:20723712

Jørgensen, H B H; Pedersen, L D; Sørensen, M K; Thomsen, P T; Norberg, E

2010-09-01

377

Relationship of severity of subacute ruminal acidosis to rumen fermentation, chewing activities, sorting behavior, and milk production in lactating dairy cows fed a high-grain diet.  

PubMed

The objectives of the current study were to evaluate the variation in severity of subacute ruminal acidosis (SARA) among lactating dairy cows fed a high-grain diet and to determine factors characterizing animals that are tolerant to high-grain diets. Sixteen ruminally cannulated late-lactating dairy cows (days in milk=282 ± 33.8; body weight=601 ± 75.9 kg) were fed a high-grain diet consisting of 35% forage and 65% concentrate mix. After 17 d of diet adaptation, chewing activities were monitored for a 24-h period and ruminal pH was measured every 30s for 72 h. Acidosis index, defined as the severity of SARA (area of pH <5.8) divided by dry matter intake (DMI), was determined for individual animals to assess the severity of SARA normalized for a feed intake level. Although all cows were fed the same diet, minimum pH values ranged from 5.16 to 6.04, and the acidosis index ranged from 0.0 to 10.9 pH · min/kg of DMI. Six cows with the lowest acidosis index (0.04 ± 0.61 pH · min/kg) and 4 with the highest acidosis index (7.67 ± 0.75 pH · min/kg) were classified as animals that were tolerant and susceptible to the high-grain diet, respectively. Total volatile fatty acid concentration and volatile fatty acid profile were not different between the groups. Susceptible animals sorted against long particles, whereas tolerant animals did not (sorting index=87.6 vs. 97.9, respectively). However, the tolerant cows had shorter total chewing time (35.8 vs. 45.1 min/kg of DMI). In addition, although DMI, milk yield, and milk component yields did not differ between the groups, milk urea nitrogen concentration was higher for tolerant cows compared with susceptible cows (12.8 vs. 8.6 mg/dL), which is possibly attributed to less organic matter fermentation in the rumen of tolerant cows. These results suggest that a substantial variation exists in the severity of SARA among lactating dairy cows fed the same high-grain diet, and that cows tolerant to the high-grain diet might be characterized by less sorting behavior but less chewing time, and higher milk urea nitrogen concentration. PMID:24612805

Gao, X; Oba, M

2014-05-01

378

Influence of novel intravenous complex solution of Ca, Mg and phosphates on blood biochemical parameters of healthy and paretic cows.  

PubMed

The article describes the dynamics of changes in blood concentrations of the active substances present in the solution after its infusion to healthy cows in comparison to NaCI solution as well as the response of paretic cows to treatment with the new complex solution. Cows received a dose of 400 ml of A1 solution (containing 8.4 g of Ca2+) intravenously. In healthy cows the average calcium concentration in blood serum prior to the test was 2.52 +/- 0.08 mmol/l while 15 min. after the infusion the concentration rose to 3.10 +/- 0.08 mmol/l (p < 0.05) and magnesium concentration rose from 0.61 +/- 0.05 to 1.39 +/- 0.08 mmol/l (p < 0.05). This experiment showed that elevated concentration of non-organic phosphates persisted 1 hour after infusion (p < 0.05). In the second phase of efficacy evaluation of the novel preparation A1 on paretic cows the intravenous injection of 1 ml/kg of body weight of A1 solution increased calcium concentration up to almost normal level (p < 0.05). The level of magnesium in serum 1 h after injection was statistically significantly higher by 63% (p < 0.05) and reached the physiologically normal concentration. 1 h after the infusion of test solution the level of phosphate was higher by 13% (p > 0.05). The rise was statistically not significant. Even though A1 solution undoubtedly produced an increase in glucose concentration in the blood serum, due to wide dispersion of individual measurements and high standard deviation the increase (p > 0.05) in glucose concentration was found insignificant. Most of the treated paretic cows rose within 1-6 h after infusion of 400 ml of solution A1. No relapses were observed. A combination of different salts of calcium and magnesium, non-organic phosphates and glucose with analeptic substance mixed in one solution (A1 solution) administered at a dose of 1 ml/kg of body weight raises concentrations of essential macroelements in blood serum of cattle and promotes improvement of paretic cows condition. PMID:18540203

Daunoras, G; Dabuzinskas, S; Matusevicius, A; Cernauskas, A

2008-01-01

379

Effects of "own" versus "alien" suckling on incidence of ovarian luteal activity, estrus and secretion of luteinizing hormone, oxytocin and prolactin in early postpartum beef cows  

E-print Network

EFFECTS OF "OWN" VERSUS "ALIEN" SUCKLING ON INCIDENCE OF OVARIAN LUTEAL ACTIVITY, ESTRUS AND SECRETION OF LUTEINIZING HORMONE, OXYTOCIN AND PROLACTIN IN EARLY POSTPARTUM BEEF COWS A Thesis by PATRICE AUVERN SILVEIRA Submitted to the Office... of Graduate Studies of Texas A8 M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1992 Major Subject: Physiology of Reproduction EFFECTS OF "OWN" VERSUS "ALIEN" SUCKLING ON INCIDENCE OF OVARIAN LUTEAL...

Silveira, Patrice Auvern

1992-01-01

380

Gluconeogenesis in dairy cows: the secret of making sweet milk from sour dough.  

PubMed

Gluconeogenesis is a crucial process to support glucose homeostasis when nutritional supply with glucose is insufficient. Because ingested carbohydrates are efficiently fermented to short-chain fatty acids in the rumen, ruminants are required to meet the largest part of their glucose demand by de novo genesis after weaning. The qualitative difference to nonruminant species is that propionate originating from ruminal metabolism is the major substrate for gluconeogenesis. Disposal of propionate into gluconeogenesis via propionyl-CoA carboxylase, methylmalonyl-CoA mutase, and the cytosolic form of phosphoenolpyruvate carboxykinase (PEPCK) has a high metabolic priority and continues even if glucose is exogenously supplied. Gluconeogenesis is regulated at the transcriptional and several posttranscriptional levels and is under hormonal control (primarily insulin, glucagon, and growth hormone). Transcriptional regulation is relevant for regulating precursor entry into gluconeogenesis (propionate, alanine and other amino acids, lactate, and glycerol). Promoters of the bovine pyruvate carboxylase (PC) and PEPCK genes are directly controlled by metabolic products. The final steps decisive for glucose release (fructose 1,6-bisphosphatase and glucose 6-phosphatase) appear to be highly dependent on posttranscriptional regulation according to actual glucose status. Glucogenic precursor entry, together with hepatic glycogen dynamics, is mostly sufficient to meet the needs for hepatic glucose output except in high-producing dairy cows during the transition from the dry period to peak lactation. Lactating cows adapt to the increased glucose requirement for lactose production by mobilization of endogenous glucogenic substrates and increased hepatic PC expression. If these adaptations fail, lipid metabolism may be altered leading to fatty liver and ketosis. Increasing feed intake and provision of glucogenic precursors from the diet are important to ameliorate these disturbances. An improved understanding of the complex mechanisms underlying gluconeogenesis may further improve our options to enhance the postpartum health status of dairy cows. PMID:21171012

Aschenbach, Jörg R; Kristensen, Niels B; Donkin, Shawn S; Hammon, Harald M; Penner, Gregory B

2010-12-01

381

Dynamical Adaptation in Photoreceptors  

PubMed Central

Adaptation is at the heart of sensation and nowhere is it more salient than in early visual processing. Light adaptation in photoreceptors is doubly dynamical: it depends upon the temporal structure of the input and it affects the temporal structure of the response. We introduce a non-linear dynamical adaptation model of photoreceptors. It is simple enough that it can be solved exactly and simulated with ease; analytical and numerical approaches combined provide both intuition on the behavior of dynamical adaptation and quantitative results to be compared with data. Yet the model is rich enough to capture intricate phenomenology. First, we show that it reproduces the known phenomenology of light response and short-term adaptation. Second, we present new recordings and demonstrate that the model reproduces cone response with great precision. Third, we derive a number of predictions on the response of photoreceptors to sophisticated stimuli such as periodic inputs, various forms of flickering inputs, and natural inputs. In particular, we demonstrate that photoreceptors undergo rapid adaptation of response gain and time scale, over ? 300 ms—i. e., over the time scale of the response itself—and we confirm this prediction with data. For natural inputs, this fast adaptation can modulate the response gain more than tenfold and is hence physiologically relevant. PMID:24244119

Clark, Damon A.; Benichou, Raphael; Meister, Markus; Azeredo da Silveira, Rava

2013-01-01

382

UNDERGRADUATE STUDENT MANUAL HUMAN PHYSIOLOGY  

E-print Network

UNDERGRADUATE STUDENT MANUAL FOR HUMAN PHYSIOLOGY 2011-2012 Revised: September, 2011 (JLS) #12;- 2 ................................................................................................................. - 3 - II. INTRODUCTION TO THE DEPARTMENT OF HEALTH SCIENCES PROGRAM IN HUMAN PHYSIOLOGY........................................................................................................................................ - 4 - III. FULL-TIME FACULTY IN HUMAN PHYSIOLOGY

Guenther, Frank

383

UNDERGRADUATE STUDENT MANUAL HUMAN PHYSIOLOGY  

E-print Network

UNDERGRADUATE STUDENT MANUAL FOR HUMAN PHYSIOLOGY 2012-2013 Revised: September, 2012 (JLS) #12;- 2 ................................................................................................................. - 3 - II. INTRODUCTION TO THE DEPARTMENT OF HEALTH SCIENCES PROGRAM IN HUMAN PHYSIOLOGY........................................................................................................................................ - 4 - III. FULL-TIME FACULTY IN HUMAN PHYSIOLOGY

Guenther, Frank

384

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

PubMed

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 0.44kgvsm(-3)d(-1) and the hydraulic retention time was 80days. 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

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

2015-04-01

385

Lung evolution as a cipher for physiology  

PubMed Central

In the postgenomic era, we need an algorithm to readily translate genes into physiologic principles. The failure to advance biomedicine is due to the false hope raised in the wake of the Human Genome Project (HGP) by the promise of systems biology as a ready means of reconstructing physiology from genes. like the atom in physics, the cell, not the gene, is the smallest completely functional unit of biology. Trying to reassemble gene regulatory networks without accounting for this fundamental feature of evolution will result in a genomic atlas, but not an algorithm for functional genomics. For example, the evolution of the lung can be “deconvoluted” by applying cell-cell communication mechanisms to all aspects of lung biology development, homeostasis, and regeneration/repair. Gene regulatory networks common to these processes predict ontogeny, phylogeny, and the disease-related consequences of failed signaling. This algorithm elucidates characteristics of vertebrate physiology as a cascade of emergent and contingent cellular adaptational responses. By reducing complex physiological traits to gene regulatory networks and arranging them hierarchically in a self-organizing map, like the periodic table of elements in physics, the first principles of physiology will emerge. PMID:19366785

Torday, J. S.; Rehan, V. K.

2009-01-01

386

Photosynthesis: Physiological and  

E-print Network

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

Ehleringer, Jim

387

Anatomy and Physiology Everyday  

NSDL National Science Digital Library

Students use information from newspaper articles to write a paper or presentation on the correlation of information from the article and their understanding of it using knowledge gained in anatomy and physiology class.

Teresa Alvarez (St. Louis Community College Forest Park AHNS)

2008-08-22

388

Physiological Steps Doctrine  

E-print Network

In vivo conversion is a process, often metabolic in nature, wherein one substance, usually a chemical compound, is altered significantly by physiological pathways in the body into one or more different substances. For example, when a patient ingests...

Torrance, Andrew W.

2008-01-01

389

Adventures in Exercise Physiology  

NSDL National Science Digital Library

The author altered the format of an exercise physiology course from traditional lecture to emphasizing daily reading quizzes and group problem-solving activities. The SALGains evaluation was used to compare the two approaches and significant improvements

Kathleen A. FitzPatrick

2004-09-01

390

Endogenous Pyrogen Physiology.  

ERIC Educational Resources Information Center

Discusses the physiology of endogenous pyrogen (EP), the fever-producing factor of cellular origin. Included are: its hormone-like role, its molecular nature, bioassay procedures, cellular production and mechanisms of EP action. (SA)

Beisel, William R.

1980-01-01

391

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...

392

The Effect of Lameness on Milk Production in Dairy Cows  

Microsoft Academic Search

Data were collected prospectively for 1.5 yr on two New York dairy farms to investigate the effect of lame- ness on milk production. The numbers of study cows (percentages treated at least once for lameness) in each herd were 1796 (52%) and 724 (40%), respectively. Lame cows were identified and treated by farm employ- ees or a professional hoof trimmer.

L. D. Warnick; D. Janssen; C. L. Guard; Y. T. Gröhn

2001-01-01

393

Mortality (including euthanasia) among Danish dairy cows (1990–2001)  

Microsoft Academic Search

Mortality among Danish dairy cows was examined using data from the Danish Cattle Database (DCD) and a questionnaire survey. Mortality risk has increased from approximately 2% in 1990 to approximately 3.5% in 1999. The increased mortality was seen for all dairy breeds and all age groups. Mortality among older dairy cows (parity 3 and older) was approximately twice the mortality

Peter T Thomsen; Anne Mette Kjeldsen; Jan Tind Sørensen; Hans Houe

2004-01-01

394

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...

395

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...

396

Milk drop due to leptospirosis in dairy cows.  

PubMed

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

2015-03-01

397

GALACTOKINETIC RESPONSES TO OXYTOCIN AND OTHER SOLUTIONS IN THE COW  

E-print Network

GALACTOKINETIC RESPONSES TO OXYTOCIN AND OTHER SOLUTIONS IN THE COW M. MORAG T.-K. GRIFFIN (1 response to oxytocin in domestic animals, MORAG and Fox (1966) concluded that the quan- titative dose for complete udder evacuation in the cow is important in view of the galactopoeitic role of oxytocin

Paris-Sud XI, Université de

398

Laryngeal obstruction caused by lymphoma in an adult dairy cow  

PubMed Central

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

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

2014-01-01

399

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...

400

Fertilizer-nitrogen: Effects on dairy cow health and performance  

Microsoft Academic Search

The effects on dairy cow health and performance of applying very high rates of inorganic fertilizer nitrogen to grassland have been studied. Two comparable areas of grassland provided the grazing and silage requirements for two separate herds of Friesian dairy cows. These two areas received 250 and 750kg fertilizer nitrogen ha-1 yr-1. The higher rate was chosen to represent a

N. B. Coombe; A. E. M. Hood

1980-01-01

401

The Economics of Organic Versus Conventional Cow-calf Production  

Microsoft Academic Search

Costs, returns, and profitability of cow-calf farms that are organic or transitioning to organic are compared with those of cow-calf farms that are non-organic. A method of matching samples is used for the comparison. Results suggest higher cost of organic production due to higher unpaid labor, taxes and insurance, and overhead costs.

Jeffrey M. Gillespie; Richard F. Nehring

2012-01-01

402

Risk factors for infertility in nursing cows linked to calving  

E-print Network

Risk factors for infertility in nursing cows linked to calving C Ducrot I Cimarosti F Bugnard with 3 590 cows in order to study the risk factors for infertility linked to calving. Based upon an analy infertility, breed factors, parity, fattening, comfort, calf characteristics (number, sex, weight

Paris-Sud XI, Université de

403

Physiology, behavior, and conservation.  

PubMed

Many animal populations are in decline as a result of human activity. Conservation practitioners are attempting to prevent further declines and loss of biodiversity as well as to facilitate recovery of endangered species, and they often rely on interdisciplinary approaches to generate conservation solutions. Two recent interfaces in conservation science involve animal behavior (i.e., conservation behavior) and physiology (i.e., conservation physiology). To date, these interfaces have been considered separate entities, but from both pragmatic and biological perspectives, there is merit in better integrating behavior and physiology to address applied conservation problems and to inform resource management. Although there are some institutional, conceptual, methodological, and communication-oriented challenges to integrating behavior and physiology to inform conservation actions, most of these barriers can be overcome. Through outlining several successful examples that integrate these disciplines, we conclude that physiology and behavior can together generate meaningful data to support animal conservation and management actions. Tangentially, applied conservation and management problems can, in turn, also help advance and reinvigorate the fundamental disciplines of animal physiology and behavior by providing advanced natural experiments that challenge traditional frameworks. PMID:24457917

Cooke, Steven J; Blumstein, Daniel T; Buchholz, Richard; Caro, Tim; Fernández-Juricic, Esteban; Franklin, Craig E; Metcalfe, Julian; O'Connor, Constance M; St Clair, Colleen Cassady; Sutherland, William J; Wikelski, Martin

2014-01-01

404

Comparison of two intravaginal progesterone releasing devices (PRID-Delta vs CIDR) in dairy cows: blood progesterone profile and field fertility.  

PubMed

Objectives were to compare circulating progesterone (P4) profile and pregnancies per AI (P/AI) of two commercial intravaginal P4 devices (PRID-Delta(®) vs CIDR(®)). In Experiment 1, ovariectomized dairy cows (PRID-Delta, n=6 vs CIDR, n=6) were sampled throughout 7 days to measure circulating P4. In Experiment 2 (PRID-Delta, n=399 vs CIDR, n=375), cows were assigned to treatments, as follows: D0, an intravaginal P4 device containing 1.38g of P4 (CIDR) or 1.55g of P4 (PRID-Delta); D6: 25mg PGF2? (Dinoprost) and P4 devices were removed 24h later. Insemination was performed at 56h after P4 removal. Cows visually detected in estrus between days 18 and 24 after 1st synchronized AI were re-inseminated. PRID-Delta produced greater circulating P4 compared to CIDR, particularly within 4 days after insertion (P<0.01). The logistic regression analysis indicated a tendency for improved P/AI at 1st AI in PRID-Delta cows compared to CIDR (36% vs 31%, P=0.10). More cows were detected in estrus in the following cycle nearly 21d after 1st AI when treated with PRID-Delta (28% vs 16%), but P/AI in the returning-natural estrus breedings did not differ (PRID-Delta=56% vs CIDR=55%; P=0.91). As a result, final cumulative P/AI was greater in cows receiving PRID-Delta (46% vs 37%, P=0.02). These results indicate that PRID-Delta seem to maintain greater circulating P4 levels as compared to CIDR in non-lactating dairy cows. This might explain potential benefits in fertility of dairy cows found in Experiment 2. Underlying physiological consequence of greater circulating P4 during synchronization programs in lactating cows in terms of oocyte quality and other reproductive structures warrants further investigation. PMID:23523234

van Werven, T; Waldeck, F; Souza, A H; Floch, S; Englebienne, M

2013-05-01

405

A graphical simulation software for instruction in cardiovascular mechanics physiology  

Microsoft Academic Search

BACKGROUND: Computer supported, interactive e-learning systems are widely used in the teaching of physiology