This study was conducted to investigate individual metabolic and endocrine adaptation to lactation under conditions of identical housing and feeding conditions in high-yielding dairy cows. Forty-five cows were studied on a research farm under standardized but practical conditions. From wk 2 before calving until wk 14 postpartum, blood samples were collected at weekly intervals and assayed for blood chemistry and various metabolites and hormones. Body weight, BCS, and backfat thickness were also recorded weekly. Milk yield, milk composition, and feed intake and energy balance were accordingly measured during the postpartum phase. The animals were retrospectively classified according to their plasma concentration of beta-hydroxybutyrate (BHB): cows in which a BHB threshold of 1 mM was exceeded at least once during the experiment were classified as BHB positive (BHB+); cows with BHB values consistently below this threshold were classified as BHB negative (BHB -). Using this classification, differences for NEFA and glucose concentrations were observed, but the mean calculated energy balance did not differ between the groups during the experimental period (-22.2 MJ of NE(1)/d +/- 4.7 for BHB+ and -18.9 MJ of NE(1)/d +/- 4.9 for BHB-). In BHB+ cows, the peripartum decrease (P < 0.05) of BW, BCS, and backfat thickness was more pronounced than in BHB- cows. Mean milk yields did not differ between groups. However, BHB+ cows had greater milk fat and lesser milk protein contents (P < 0.05), resulting in a greater (P < 0.05) fat:protein ratio than in BHB- cows. Thus, to some extent, cows were able to compensate for the negative energy balance by adjustments in performance. Milk acetone concentrations followed BHB concentrations in blood. Insulin-like growth factor-I and leptin concentrations were greater (P < 0.05) in BHB- cows during the time of observation than in the BHB+ cows. Comparing the reproductive variables recorded (first increase of progesterone, first service conception rate, number of services per conception, interval from calving to first AI, interval from first AI to conception, and days open) between the 2 groups yielded no significant differences. Our findings imply that despite comparable energy balance, there is considerable individual variation of the adaptive ability of cows during early lactation based on a variety of metabolic and endocrine variables. PMID:18599666
Kessel, S; Stroehl, M; Meyer, H H D; Hiss, S; Sauerwein, H; Schwarz, F J; Bruckmaier, R M
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...
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 (;)
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
In the present study, 50 samples of mother milk and 20 samples of adapted cow's milk produced for bottle feeding supplied from the lactarium of the Pediatric Hospital were examined for presence of 6 indicator congeners of polychlorinated biphenyls (IUPAC No. 28, 52, 101, 138, 153, and 180). Congeners No. 138, 153, and 180 were predominant in all samples, the highest mean as well as the maximum level was found for No. 138 for both type of samples. The average daily intake based on the sum of indicator congeners was found to be 2.56 micrograms. (kgb.w..day)-1 for mother milk, and 0.85 microgram.(kgb.w..day)-1 for adapted cow's milk. PMID:8044629
Prachar, V; Veningerová, M; Uhnák, J; Kovacicová, J
The seasonal variations of the level of serum total proteins and their electrophoretic fractions in dairy cows, living in\\u000a the Mediterranean area, were investigated. During different physiological phases, ten dairy cows were housed in a sheltered\\u000a pen in Sicily (Italy). Throughout the experimental period, ambient temperature and relative humidity were continuously recorded\\u000a with a data logger and temperature humidity index
Giuseppe Piccione; Vanessa Messina; Daniela Alberghina; Claudia Giannetto; Stefania Casella; Anna Assenza
Twenty Holstein friesian and Brown swiss cows were used to investigate the effect of insufficient in barn ventilation on blood gas status and some physiological traits of the cows. Animals were kept in mechanically ventilated barn in stall barn (I); and the ventilation funnels of the barn were closed to simulate traditional habits of the region's breeders (II); then cows were transfered open-shed barn (III). For each experimental of 10 days period, respiration and pulse rates and blood gas of animals were measured. Temperature, relative humidity, CO2 and NH3 concentrations were recorded in each barns. In mechanically ventilated barn, climatic and atmospheric gas was in normal ranges for the cows but in unventilated barn they were at the upper levels. In experiment II, blood pH was decreased without pCO2 change. The highest blood pO2 and HCO3(-) levels were found when the animals were kept in open-shed barn (III). Measured parameters were not influenced by breed of the cows. Blood pH, pO2 HCO3(-), respiration and pulse rates of the cows were significantly affected by barn types (p < 0.05 and p < 0.01). Respiration and pulse rates were higher in inadequate (II) barn conditions than those of open-shed. Higher levels of gases, especially carbon dioxide, in the unventilated barn significantly influenced biological parameters of cows. It is concluded that poor ventilation caused considerable changes in physiologic parameters of the cows and can potentially affect animal health and production. PMID:18831341
Sabuncuoglu, N; Coban, O; Lacin, E; Yildiz, A; Akbulut, O; Yaganoglu, A V; Sagsoz, Y
This manuscript focuses on potential changes in reproductive physiology that occur due to high milk production in lactating dairy cows. Four reproductive measures are discussed: interval to first ovulation, conception rate, duration of estrus, and multiple ovulation rate. The last two responses have now been closely linked to level of milk production. In contrast, time to first ovulation does not
Milo Wiltbank; Hernando Lopez; Roberto Sartori; Siwat Sangsritavong; Ahmet Gümen
Three entosymbiotic graffillid rhabdocoels (Paravortex scrobiculariae, P. cardii and Graffilla buccinicola) from marine bivalve and gastropod molluscs show several physiological adaptations to their life-style which are intimately related to the nutritional physiology and ecology of their respective hosts.
J. B. Jennings; Baines Wing
|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.
This document is focused on describing how, technically, implementing adaptive technology and supplemental curriculum for Anatomy and Physiology is developed from a functional use aspect including Functionality Use Case Scenarios, Technical Architecture O...
B. Sahota S. Nagarathnam T. Mathur
Effects of a progressive change in 6 wk from a urea-free concentrate to one providing .34 (medium) or .66 g (high) urea\\/kg body weight on jugular blood composition and animal performance were studied with 27 cows. Consumption of dry matter was not affected even at the high rate of urea intake. Milk produc- tion was maximum when after 6 wk
P. R. Narasimhalu; R. J. Belzile; G. J. Brisson; W. B. Holtman
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
Background Weaning involves the permanent separation of the calf from the dam and has been shown to be stressful for both. The objectives of this study were to characterise the effect of i) abrupt weaning and ii) subsequent housing on the extended physiological and immunological responses of beef cows. At weaning (day (d) 0, mean age of calf (s.d.) 212 (24.5) d), cows were abruptly separated from their calves and returned to the grazing area. After 35 d at pasture, cows were housed in a slatted floor shed and offered grass silage ad libitum plus a mineral-vitamin supplement daily. Rectal body temperature was recorded and blood samples were obtained on i) d 0 (weaning), 2, 7, 14, 21, 28, 35 and subsequently on ii) d 0 (housing), 2, 7, 14 and 21 for physiological, haematological and immunological measurements. Results Post-weaning, concentration of cortisol and dehydroepiandrosterone were unchanged (P > 0.05). Rectal body temperature, neutrophil number and neutrophil: lymphocyte ratio increased (P < 0.01) on d 2 compared with pre-weaning baseline. Lymphocyte and neutrophil number decreased (P < 0.05) on d 2 to 7 and d 7 to 21, respectively, compared with pre-weaning baseline. Interferon-? production decreased (P < 0.05) on d 2 compared with pre-weaning baseline. An increase (P < 0.05) in acute phase proteins, fibrinogen and haptoglobin was evident on d 2 to 35 compared with pre-weaning baseline. Concentration of glucose increased on d 2 to 28, whereas non-esterified fatty acid decreased on d 2 to 35 compared with pre-weaning baseline. Post-housing, concentrations of cortisol, rectal body temperature, total leukocyte number, and glucose were unchanged (P > 0.05). On d 2 post-housing, neutrophil number and neutrophil: lymphocyte ratio increased (P < 0.05), whereas lymphocyte number and concentrations of dehydroepiandrosterone, fibrinogen and non-esterified fatty acid decreased (P < 0.05) compared with pre-housing baseline. Concentration of haptoglobin increased (P < 0.05) on d 14 to 21 post-housing. Conclusions A transitory increase in neutrophil number and decrease in lymphocyte number, increased neutrophil:lymphocyte ratio coupled with decreased interferon-? production, and increased concentration of acute phase proteins indicate a stress response in cows post-weaning, whereas post-housing, changes were less marked.
Temperature profoundly influences physiological responses in animals, primarily due to the effects 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 and evolutionary physiology. Animals may either defend a fairly constant temperature by recruiting biochemical mechanisms of heat production and utilizing physiological responses geared toward modifying heat loss and heat gain from the environment, or utilize biochemical modifications to allow for physiological adjustments to temperature. Biochemical adaptations to temperature involve alterations in protein structure that compromise the effects of increased temperatures on improving catalytic enzyme function with the detrimental influences of higher temperature on protein stability. Temperature has acted to shape the responses of animal proteins in manners that generally preserve turnover rates at animals' normal, or optimal, body temperatures. Physiological responses to cold and warmth differ depending on whether animals maintain elevated body temperatures (endothermic) or exhibit minimal internal heat production (ectothermic). In both cases, however, these mechanisms involve regulated neural and hormonal over heat flow to the body or heat flow within the body. Examples of biochemical responses to temperature in endotherms involve metabolic uncoupling mechanisms that decrease metabolic efficiency with the outcome of producing heat, whereas ectothermic adaptations to temperature are best exemplified by the numerous mechanisms that allow for the tolerance or avoidance of ice crystal formation at temperatures below 0°C. PMID:23723035
Tattersall, Glenn J; Sinclair, Brent J; Withers, Philip C; Fields, Peter A; Seebacher, Frank; Cooper, Christine E; Maloney, Shane K
When a woman learns that she is pregnant, her emotions are like a roller coaster. To her, she is pregnant. She begins to plan all the things that could be and is in constant motion to await the 9 months until the arrival of her bundle of joy. However, to those of us in the perinatal nursing field, it means so much more. The pregnant woman's body goes through some profound anatomical, physiologic, and biochemical changes to adapt to and support the entire pregnancy, which ultimately support the growing fetus. Although these physiologic changes are normal, often they can be misinterpreted as disease. These changes may also unmask or worsen a preexisting condition or disease, ultimately because the pregnant woman's body cannot adequately adapt to the changes of pregnancy. It is essential to know and understand the physiology-the inner workings-of both the mother and the fetus. This includes the basic adaptations related to pregnancy, placental physiology and action, uterine activity physiology, and fetal heart rate regulation, although this article will focus on maternal and uterine physiology only. PMID:16456359
Torgersen, Keiko L; Curran, Carol A
Stress factors are so numerous and so diverse in their strength and duration that the consequences on animal welfare can be quite varied. The first important distinction concerns the characterization of acute and chronic stress conditions. Acute stress is a short-lived negative situation that allows a quick and quite complete recovery of the physiological balance (adaptation), while chronic stress is
Erminio Trevisi; Giuseppe Bertoni
This review focuses on research on both the neural substrate of maternal responsiveness and on the physiological, behavioral, and motivational adaptations to the maternal state. The female's response to her young is presented as a model motivational system and the mechanisms and neural circuitry through which the medial preoptic area regulates this responsivity is described. This analysis is then used
Michael Numan; Barbara Woodside
This paper explores the use of human physiology in adaptive game mechanics. The study shows evidence that galvanic skin response (GSR) can react to stress changes caused by game difficulties and that GSR positively and significantly correlates with negative game events (frustration events) rather than positive events (success events); moreover, continuous failures during game playing can trigger distress (negative stress),
Shaomei Wu; Tao Lin
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
Evolutionary solutions to the physiological challenges of life in highly variable habitats can span the continuum from evolution of a cosmopolitan plastic phenotype to the evolution of locally adapted phenotypes. Killifish (Fundulus sp.) have evolved both highly plastic and locally adapted phenotypes within different selective contexts, providing a comparative system in which to explore the genomic underpinnings of physiological plasticity and adaptive variation. Importantly, extensive variation exists among populations and species for tolerance to a variety of stressors, and we exploit this variation in comparative studies to yield insights into the genomic basis of evolved phenotypic variation. Notably, species of Fundulus occupy the continuum of osmotic habitats from freshwater to marine and populations within Fundulus heteroclitus span far greater variation in pollution tolerance than across all species of fish. Here, we explore how transcriptome regulation underpins extreme physiological plasticity on osmotic shock and how genomic and transcriptomic variation is associated with locally evolved pollution tolerance. We show that F. heteroclitus quickly acclimate to extreme osmotic shock by mounting a dramatic rapid transcriptomic response including an early crisis control phase followed by a tissue remodeling phase involving many regulatory pathways. We also show that convergent evolution of locally adapted pollution tolerance involves complex patterns of gene expression and genome sequence variation, which is confounded with body-weight dependence for some genes. Similarly, exploiting the natural phenotypic variation associated with other established and emerging model organisms is likely to greatly accelerate the pace of discovery of the genomic basis of phenotypic variation.
Galvez, Fernando; Zhang, Shujun; Williams, Larissa M.; Oleksiak, Marjorie F.
The hypothesis was that sensors currently available on farm that monitor behavioral and physiological characteristics have potential for the detection of lameness in dairy cows. This was tested by applying additive logistic regression to variables derived from sensor data. Data were collected between November 2010 and June 2012 on 5 commercial pasture-based dairy farms. Sensor data from weigh scales (liveweight), pedometers (activity), and milk meters (milking order, unadjusted and adjusted milk yield in the first 2min of milking, total milk yield, and milking duration) were collected at every milking from 4,904 cows. Lameness events were recorded by farmers who were trained in detecting lameness before the study commenced. A total of 318 lameness events affecting 292 cows were available for statistical analyses. For each lameness event, the lame cow's sensor data for a time period of 14d before observation date were randomly matched by farm and date to 10 healthy cows (i.e., cows that were not lame and had no other health event recorded for the matched time period). Sensor data relating to the 14-d time periods were used for developing univariable (using one source of sensor data) and multivariable (using multiple sources of sensor data) models. Model development involved the use of additive logistic regression by applying the LogitBoost algorithm with a regression tree as base learner. The model's output was a probability estimate for lameness, given the sensor data collected during the 14-d time period. Models were validated using leave-one-farm-out cross-validation and, as a result of this validation, each cow in the data set (318 lame and 3,180 nonlame cows) received a probability estimate for lameness. Based on the area under the curve (AUC), results indicated that univariable models had low predictive potential, with the highest AUC values found for liveweight (AUC=0.66), activity (AUC=0.60), and milking order (AUC=0.65). Combining these 3 sensors improved AUC to 0.74. Detection performance of this combined model varied between farms but it consistently and significantly outperformed univariable models across farms at a fixed specificity of 80%. Still, detection performance was not high enough to be implemented in practice on large, pasture-based dairy farms. Future research may improve performance by developing variables based on sensor data of liveweight, activity, and milking order, but that better describe changes in sensor data patterns when cows go lame. PMID:24011945
Kamphuis, C; Frank, E; Burke, J K; Verkerk, G A; Jago, J G
Cardiac hypertrophy is a stereotypic response of the heart to increased workload. The nature of the workload increase may vary depending on the stimulus (repetitive, chronic, pressure, or volume overload). If the heart fully adapts to the new loading condition, the hypertrophic response is considered physiological. If the hypertrophic response is associated with the ultimate development of contractile dysfunction and heart failure, the response is considered pathological. Although divergent signalling mechanisms may lead to these distinct patterns of hypertrophy, there is some overlap. Given the close relationship between workload and energy demand, any form of cardiac hypertrophy will impact the energy generation by mitochondria, which are the key organelles for cellular ATP production. Significant changes in the expression of nuclear and mitochondrially encoded transcripts that impact mitochondrial function as well as altered mitochondrial proteome composition and mitochondrial energetics have been described in various forms of cardiac hypertrophy. Here, we review mitochondrial alterations in pathological and physiological hypertrophy. We suggest that mitochondrial adaptations to pathological and physiological hypertrophy are distinct, and we shall review potential mechanisms that might account for these differences.
Abel, E. Dale; Doenst, Torsten
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
Electrocardiographic changes in athletes are common and usually reflect benign structural and electrical remodelling of the heart as a physiological adaptation to regular and sustained physical training (athlete's heart). The ability to identify an abnormality on the 12-lead ECG, suggestive of underlying cardiac disease associated with sudden cardiac death (SCD), is based on a sound working knowledge of the normal ECG characteristics within the athletic population. This document will assist physicians in identifying normal ECG patterns commonly found in athletes. The ECG findings presented as normal in athletes were established by an international consensus panel of experts in sports cardiology and sports medicine. PMID:23303759
Drezner, Jonathan A; Fischbach, Peter; Froelicher, Victor; Marek, Joseph; Pelliccia, Antonio; Prutkin, Jordan M; Schmied, Christian M; Sharma, Sanjay; Wilson, Mathew G; Ackerman, Michael John; Anderson, Jeffrey; Ashley, Euan; Asplund, Chad A; Baggish, Aaron L; Börjesson, Mats; Cannon, Bryan C; Corrado, Domenico; DiFiori, John P; Harmon, Kimberly G; Heidbuchel, Hein; Owens, David S; Paul, Stephen; Salerno, Jack C; Stein, Ricardo; Vetter, Victoria L
During summer, 34 cows received daily injections of placebo or 25 mg of bST and were placed in a thermoregulated or a heat stress environment. Heat stress increased rectal temperatures, respiration rates, and plasma cortisol concentrations and decreased milk yield. Four of 9 bST-treated cows and none of 8 control cows became atactic on the 1st d of heat stress. When exposed to heat stress, cows treated with bST experienced higher rectal temperatures throughout the trials than cows treated with placebo. Nonetheless, bST increased milk yields in both environments. The major effect of heat stress on immune function was decreased migration of leukocytes to the mammary gland after chemotactic challenge. This effect of heat stress was not altered by bST. In summary, hyperthermia induced by heat stress and associated changes were greater for cows treated with bST. Detected effects of heat stress on the immune system were few and were not alleviated by bST. Use of bST during summer in subtropical climate zones requires careful management to avoid overexposure of bST-treated cows to heat stress. PMID:1560140
Elvinger, F; Natzke, R P; Hansen, P J
The physiological and genetical adaptation of fishes to environmental temperatures has been studied by analyzing data concerning: (i) the oxygen binding properties of haemoglobin recorded during growth experiments on Atlantic cod, and (ii) the primary structure of haemoglobin (Hb) and lactate dehydrogenase (LDH) of several fish species living in polar and temperate areas. The results on the oxygen binding properties of cod's haemoglobin indicate that for this species a temperature of around 12°C is the most favourable one, irrespective of the haemoglobin genotype, and are in line with recent evidence challenging the existence of significant evolutionary differences between cod stocks in North Atlantic. The primary structures of both Hb and LDH from species living under temperate environments show a higher variability as compared to that from polar species, although the difference in the recurrent patterns of hydrophobicity between the two areas is much larger for Hb. These results highlight the dominant role of physiological and genetical factors in shaping the adaptation to temperature at the individual and at the species level, respectively.
Colosimo, A.; Giuliani, A.; Maranghi, F.; Brix, O.; Thorkildsen, S.; Fischer, T.; Knust, R.; Poertner, H. O.
We report mechanically adaptive bionanocomposites based on poly(vinyl alcohol) (PVOH) and cellulose nanocrystals (CNCs), whose mechanical properties change significantly upon exposure to simulated physiological conditions. These nanocomposites were made using CNCs derived from tunicates (t-CNCs) and cotton (c-CNCs) to explore how aspect ratio, surface charge density, and filler content influence the mechanical properties. Dynamic mechanical analysis data reveal a significant enhancement of the tensile storage modulus (E') upon introduction of CNCs, which scaled with the CNC type and content. For example, in the dry, glassy state at 25 °C, E' increased up to 23% (for c-CNCs) and 88% (for t-CNCs) compared to the neat polymer. Exposing the materials to simulated physiological conditions caused a drastic softening of the materials, from 9.0 GPa to 1 MPa for c-CNCs and from 13.7 GPa to 160 MPa for t-CNCs. The data show that the swelling characteristics of the nanocomposites and the extent of mechanical switching could be influenced via the amount and type of CNCs and also the processing conditions. The high stiffness in the dry state and the ability to tailor the mechanical contrast via composition and processing makes the new materials particularly useful as basis for adaptive biomedical implants. PMID:23379302
Jorfi, Mehdi; Roberts, Matthew N; Foster, E Johan; Weder, Christoph
The pain and distress associated with transcutaneous electrical nerve stimulation (TENS) of the udder was evaluated by treating 20 healthy dairy cows with an electrical udder stimulator. This generated a sequence of pulses (frequency: 160±10% impulses per second, duration 250 ?s) and provided voltage ranges from 0 to 10 volts (±10%). Trials took place on three consecutive days, twice daily after morning and evening milking. Daily sessions were divided into two periods: (1) control (sham treatment) and (2) treatment (real treatment). Physiological (heart rate, respiratory rate, and plasma cortisol concentration) as well as ethological parameters (kicking, weight shifting, and looking backwards to udder) were defined as pain-indicating parameters and observed. Evaluation of data showed that only one parameter (kicking) was significantly increased during real treatment compared to sham treatment. It is concluded that the TENS therapy tested in this study can evoke changes in behaviour (increased kicking) consistent with an experience of pain in some cows. PMID:21733723
Kirscher, Franziska; Bruckmaier, Rupert M; Spadavecchia, Claudia; Friedli, Katharina; Doherr, Marcus G; Syring, Claudia; Steiner, Adrian
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
Most exercise scientists would agree that the physiological determinants of peak endurance performance include the capacity to transport oxygen to the working muscle, diffusion from the muscle to the mitochondria, energy production and force generation, all influenced by signals from the central nervous system. In general, the capacity of the pulmonary system far exceeds the demands required for ventilation and gas exchange during exercise. Endurance training induces large and significant adaptations within the cardiovascular, musculoskeletal and haematological systems. However, the structural and functional properties of the lung and airways do not change in response to repetitive physical activity and, in elite athletes, the pulmonary system may become a limiting factor to exercise at sea level and altitude. As a consequence to this respiratory paradox, highly trained athletes may develop intrathoracic and extrathoracic obstruction, expiratory flow limitation, respiratory muscle fatigue and exercise-induced hypoxaemia. All of these maladaptations may influence performance. PMID:22267571
McKenzie, Donald C
Comparisons among species have been a standard tool in animal physiology to understand how organisms function and adapt to their surrounding environment. During the last two decades, conceptual and methodological advances from different fields, including evolutionary biology and systematics, have revolutionized the way comparative analyses are performed, resulting in the advent of modern phylogenetic statistical methods. This development stems from the realization that conventional analytical methods assume that observations are statistically independent, which is not the case for comparative data because species often resemble each other due to shared ancestry. By taking evolutionary history explicitly into consideration, phylogenetic statistical methods can account for the confounding effects of shared ancestry in interspecific comparisons, improving the reliability of standard approaches such as regressions or correlations in comparative analyses. Importantly, these methods have also enabled researchers to address entirely new evolutionary questions, such as the historical sequence of events that resulted in current patterns of form and function, which can only be studied with a phylogenetic perspective. Here, we provide an overview of phylogenetic approaches and their importance for studying the evolution of physiological processes and mechanisms. We discuss the conceptual framework underlying these methods, and explain when and how phylogenetic information should be employed. We then outline the difficulties and limitations inherent to comparative approaches and discuss potential problems researchers may encounter when designing a comparative study. These issues are illustrated with examples from the literature in which the incorporation of phylogenetic information has been useful, or even crucial, for inferences on how species evolve and adapt to their surrounding environment. PMID:23728983
Rezende, Enrico L; Diniz-Filho, José Alexandre F
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.
The aim of the study was to compare physiological responses between runners adapted and not adapted to deep water running at maximal intensity and the intensity equivalent to the ventilatory threshold. Seventeen runners, either adapted (n = 10) or not adapted (n = 7) to deep water running, participated in the study. Participants in both groups undertook a maximal treadmill running and deep water
Liane B. Azevedo; Mike I. Lambert; Paulo S. Zogaib; Turibio L. Barros Neto
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
M. R. Gallardo; S. E. Valtorta; P. E. Leva; M. C. Gaggiotti; G. A. Conti; R. F. Gregoret
Many freshwater turtles in temperate climates may experience winter periods trapped under ice unable to breathe, in anoxic mud, or in water depleted of O(2). To survive, these animals must not only retain function while anoxic, but they must do so for extended periods of time. Two general physiological adaptive responses appear to underlie this capacity for long-term survival. The first is a coordinated depression of metabolic processes within the cells, both the glycolytic pathway that produces ATP and the cellular processes, such as ion pumping, that consume ATP. As a result, both the rate of substrate depletion and the rate of lactic acid production are slowed greatly. The second is an exploitation of the extensive buffering capacity of the turtle's shell and skeleton to neutralize the large amount of lactic acid that eventually accumulates. Two separate shell mechanisms are involved: release of carbonate buffers from the shell and uptake of lactic acid into the shell where it is buffered and sequestered. Together, the metabolic and buffering mechanisms permit animals to survive for 3-4 months at 3 degrees C with no O(2) and with circulating lactate levels of 150 mmol l(-1) or more. PMID:12231634
Jackson, Donald C
\\u000a A data base has been generated by using results reported in refereed papers that have assessed the effect of heat stress on\\u000a dairy cows. Studied parameters have been evaluated using variance- covariance analysis to separate between and within variations.\\u000a Simple and multiple polynomial or quadratic regressions were carried out to quantify the heat stress effects on nutritional\\u000a parameters. The main
T. Najar; M. Rejeb; M. Ben M Rad
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. Our objectives were to (1) determine the effect of stage of lactation and milk yield on metabolic and production responses of cows during a nutrient restriction period to experimentally increase PI; (2) identify major metabolites that relate to degree of PI; and (3) identify potential biomarkers in milk for on-farm detection of PI throughout lactation. Forty-seven Holstein cows in early [n=14; 49±22 d in milk (DIM); parity=1.6±0.5], mid (n=15; 159±39 DIM; parity=1.5±0.5), and late (n=18; 273±3 DIM; parity=1.3±0.5) lactation were used. Prior to restriction, all cows were fed the same total mixed ration ad libitum. All cows were then nutrient restricted for 4 d by supplementing the ration with 60% wheat straw to induce PI. After restriction, cows returned to full feed. Daily milk yield was recorded and composite milk samples were analyzed for fat, protein, lactose, citrate, somatic cells, uric acid, alkaline phosphatase, ?-hydroxybutyrate (BHBA), and milk urea nitrogen. Blood was collected daily and analyzed for metabolites: nonesterified fatty acids (NEFA), BHBA, glucose, plasma urea nitrogen, and insulin. The revised quantitative insulin sensitivity check index (RQUICKI) was calculated for each cow. Liver biopsies collected before and during restriction were analyzed for triglycerides, glycogen, phospholipids, glucose, and total lipid content. A generalized linear mixed model was used to determine the effect of stage of lactation on responses during restriction. Regression analyses were used to examine the effect of pre-restriction levels on changes during restriction. Similar decreases in milk yield among groups indicate that the capacity of individual responses is dependent on milk yield but the coping strategies used are dependent on stage of lactation. Milk yield was a better predictor of feed intake than DIM. Plasma glucose decreased for all cows, and cows in early lactation had increased plasma BHBA, whereas cows in later lactation had increased NEFA during restriction. Milk citrate had the greatest increase (58%) during restriction for all cows. Results reported here identified metabolites (i.e., glucose, NEFA, BHBA, cholesterol) as predictors of PI and identified milk citrate as a promising biomarker for PI on farm. PMID:22541465
Bjerre-Harpøth, V; Friggens, N C; Thorup, V M; Larsen, T; Damgaard, B M; Ingvartsen, K L; Moyes, K M
Progress in molecular plant breeding is limited by the ability to predict plant phenotype based on its genotype, especially for complex adaptive traits. Suitably constructed crop growth and development models have the potential to bridge this predictability gap. A generic cereal crop growth and development model is outlined here. It is designed to exhibit reliable predictive skill at the crop level while also introducing sufficient physiological rigour for complex phenotypic responses to become emergent properties of the model dynamics. The approach quantifies capture and use of radiation, water, and nitrogen within a framework that predicts the realized growth of major organs based on their potential and whether the supply of carbohydrate and nitrogen can satisfy that potential. The model builds on existing approaches within the APSIM software platform. Experiments on diverse genotypes of sorghum that underpin the development and testing of the adapted crop model are detailed. Genotypes differing in height were found to differ in biomass partitioning among organs and a tall hybrid had significantly increased radiation use efficiency: a novel finding in sorghum. Introducing these genetic effects associated with plant height into the model generated emergent simulated phenotypic differences in green leaf area retention during grain filling via effects associated with nitrogen dynamics. The relevance to plant breeding of this capability in complex trait dissection and simulation is discussed. PMID:20400531
Hammer, Graeme L; van Oosterom, Erik; McLean, Greg; Chapman, Scott C; Broad, Ian; Harland, Peter; Muchow, Russell C
A comparative study of physiological shifts in people when changing their residence showed that the adaptation to mountain as well as desert conditions proceeds in 'northerners' at a slower rate than in 'southerners'. Indices of the cardiovascular system,...
M. F. Avazbakieva
Cardiomyocytes (CMCs) adapt to physiological or pathological stimuli by undergoing molecular changes which differentiate according to the specificity of the stimulus and eventually generate a phenotype with peculiar molecular characteristics. Here, we review the literature on the molecular mechanisms activated in the CMC during physiologic adaptation to stress, as opposed to maladaptation. The critical role of the IGF-1 receptor/PI3K/Akt signaling pathway during this process is described, including effector targets regulating inotropism and cell size. PMID:15522267
Ceci, Marcello; Ross, John; Condorelli, Gianluigi
ABSTRACT Temperature is the most important abiotic factor affecting physiology, ecology and evolution inectotherms.,Do organisms ,broadly ,distributed along a latitudinal ,gradient adapt to local differences in temperature? In ectotherms this question has played a central role in evolutionary physiology. By means of an extensive field study and laboratory experiments, we tested the existence of local adaptations,in thermal traits along 10of
Luis E. Castañeda; A. Lardies; Francisco Bozinovic
Wyon, M., and E. Redding. Physiological monitoring of cardiorespiratory adaptations during rehearsal and perfor- mance of contemporary dance. J. Strength Cond. Res. 19(3):000- 000. 2005.Previous research has shown that dance class and rehearsal stress different cardiorespiratory energy systems than dance performance. The aim of the present study was to monitor the physiological parameters of a number of dancers during a
Matthew A. Wyon; Emma Redding
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. 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
Since any given trait of an organism is considered to represent either an adaptation to the environment or a phylogenetic constraint, most physiological gut characteristics should be adaptive in terms of optimizing digestion and utilization of the respective food source. Among the Crustacea, the taxon Oniscidea (Isopoda) is the only suborder that includes, and essentially consists of, species inhabiting terrestrial
Martin Zimmer; Andreas Brune
Browse foliages from Lysiloma acapulcencis, Quercus laeta and Pithecellobium dulce, native to the subtropical region of southern México, were harvested during the dry season (DS) and rainy season (RS) to determine in situ degradability using ruminal inoculum from fistulated cows as well as goats previously adapted (AG) or not adapted (UG) to browse species fed in their daily diet. Browse
L. M. Camacho; R. Rojo; A. Z. M. Salem; F. D. Provenza; G. D. Mendoza; F. Avilés; O. D. Montañez-Valdez
When subjected to a period of oxygen deprivation, endothelial cells exhibit a characteristic pattern of responses that can be considered either adaptive or pathologic, depending on the circumstances. In this review, the molecular basis for these responses is detailed. Hypoxia shifts the endothelial phenotype towards one in which anticoagulant properties are diminished, permeability and leukoadhesivity are increased, and proinflammatory features dominate the endovascular milieu. Of all the different points of intersection between the coagulation and inflammatory axes in the vasculature, perhaps most fundamentally, hypoxia alters several key transcriptional factors, including early growth response gene 1 (Egr1) and hypoxia-inducible factor (HIF) 1, which coordinate separate programs of gene activation. The preponderance of forces in the hypoxic endovascular environment, perhaps designed as an evolutionary adaptation to oxygen deprivation, can trigger severe, pathologic, clinical consequences in the setting of tissue ischemia. PMID:12386504
Ten, Vadim S; Pinsky, David J
Many vertebrate animals have superior tolerance to environmental hypoxia compared to humans. For example, turtles tolerate an environment of 100% N2 for several hours, without apparent ill effect. This hypoxia tolerance is not limited to heterotherms, as some species of marine mammals, such as the northern elephant seal, may voluntarily dive for periods of up to 2 hours. Torpid bats exhibit prolonged periods of apnea and passive diffusion of oxygen down their trachea through an open glottis supplies a significant amount of the oxygen uptake. The Ruppell's griffon holds the known avian record of flight at 11,278 m, and other birds regularly migrate at altitudes over 8000m. These animals exhibit diverse adaptations for tolerating their hypoxic environment, many of which are poorly understood. Some of theses strategies include 1) the ability to lower metabolic rate when exposed to hypoxia 2) the ability to recruit alternate biochemical pathways for energy production 3) a left shifted oxy-hemoglobin dissociation curve 4) more efficient pulmonary gas exchange 5) the ability to alter blood flow distribution under hypoxic stress. Although there are common themes of animal adaptation to hypoxic stress, many animal solutions are unique. PMID:11950136
Hopkins, S R; Powell, F L
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.
Monneveux, Philippe; Jing, Ruilian; Misra, Satish C.
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
There are well known mechanistic similarities 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 of the diving response in pinnipeds, we found conservative and adaptable physiological characters involved in human responses to hypoxia. Because the analysis concerns traits within a single species, conservative characters dominate the picture (they define basic human physiology and largely are independent of environmental parameters). Most notably, we also found evidence for adaptable characters forming the foundations for a fairly unique physiological phenotypea low capacity version favored under hypobaric hypoxia and a high capacity one favored for endurance performance. Because current evidence implies that the human species arose under conditions that were getting colder, drier, and higher (situations in which these traits would have been advantageous), we hypothesize that this physiology is our ancestral condition.
Hochachka, Peter W.; Gunga, Hanns Christian; Kirsch, Karl
|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.
The results of more than two decades of intensive research on the physiological and biochemical features of the lugworm are reviewed with the aim of drawing a general and comprehensive picture of the adaptation of this species to the special conditions of living in the tidal zone, which may also hold true for the majority of invertebrates found in this habitat.
Zebe, E.; Schiedek, D.
Changes in anthropometric and hematological values and parameters of cardiovascular function indicated sufficiently effective adaptation of first-year students to studies at higher educational institutions. On the other hand, a certain strain of the physiological optimum caused by examination stress was found in the students. PMID:22451865
Panikhina, A V
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
Adaptation and transformation biology of the mitochondrion to redox status is an emerging domain of physiology and pathophysiology. Mitochondrial adaptations occur in response to accidental changes in cellular energy demand or supply while mitochondrial transformations are a part of greater program of cell metamorphosis. The possible role of mitochondrial adaptations and transformations in pathogenesis remains unexplored, and it has become critical to decipher the stimuli and the underlying molecular pathways. Immediate activation of mitochondrial function was described during acute exercise, respiratory chain injury, Endoplasmic Reticulum stress, genotoxic stress, or environmental toxic insults. Delayed adaptations of mitochondrial form, composition, and functions were evidenced for persistent changes in redox status as observed in endurance training, in fibroblasts grown in presence of respiratory chain inhibitors or in absence of glucose, in the smooth muscle of patients with severe asthma, or in the skeletal muscle of patients with a mitochondrial disease. Besides, mitochondrial transformations were observed in the course of human cell differentiation, during immune response activation, or in cells undergoing carcinogenesis. Little is known on the signals and downstream pathways that govern mitochondrial adaptations and transformations. Few adaptative loops, including redox sensors, kinases, and transcription factors were deciphered, but their implication in physiology and pathology remains elusive. Mitoplasticity could play a protective role against aging, diabetes, cancer, or neurodegenerative diseases. Research on adaptation and transformation could allow the design of innovative therapies, notably in cancer. PMID:22989324
Jose, Caroline; Melser, Su; Benard, Giovanni; Rossignol, Rodrigue
The presence of physiological noise in functional MRI can greatly limit the sensitivity and accuracy of BOLD signal measurements, and produce significant false positives. There are two main types of physiological confounds: (1) high-variance signal in non-neuronal tissues of the brain including vascular tracts, sinuses and ventricles, and (2) physiological noise components which extend into gray matter tissue. These physiological effects may also be partially coupled with stimuli (and thus the BOLD response). To address these issues, we have developed PHYCAA+, a significantly improved version of the PHYCAA algorithm (Churchill et al., 2011) that (1) down-weights the variance of voxels in probable non-neuronal tissue, and (2) identifies the multivariate physiological noise subspace in gray matter that is linked to non-neuronal tissue. This model estimates physiological noise directly from EPI data, without requiring external measures of heartbeat and respiration, or manual selection of physiological components. The PHYCAA+ model significantly improves the prediction accuracy and reproducibility of single-subject analyses, compared to PHYCAA and a number of commonly-used physiological correction algorithms. Individual subject denoising with PHYCAA+ is independently validated by showing that it consistently increased between-subject activation overlap, and minimized false-positive signal in non gray-matter loci. The results are demonstrated for both block and fast single-event task designs, applied to standard univariate and adaptive multivariate analysis models. PMID:23727534
Churchill, Nathan W; Strother, Stephen C
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
Soil bacteria need to adapt quickly to changes in the environmental conditions. Physiological adaptation plays an important\\u000a role in microbial survival, especially under stressful conditions. Here the abilities of chemicals and pesticides to modulate\\u000a physiological adaptive and cross-protective responses, that make the bacteria more resistant to oxidative stress, are examined\\u000a in the soil bacterium and phytopathogen, Xanthomonas. The genetic basis
Skorn Mongkolsuk; James M. Dubbs; Paiboon Vattanaviboon
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
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. PMID:23423437
Gui, Dan Y; Lewis, Caroline A; Vander Heiden, Matthew G
Novel or changing environments expose animals to diverse stressors that likely require coordinated hormonal and behavioral adaptations. Predicted adaptations to urban environments include attenuated physiological responses to stressors and bolder exploratory behaviors, but few studies to date have evaluated the impact of urban life on codivergence of these hormonal and behavioral traits in natural systems. Here, we demonstrate rapid adaptive shifts in both stress physiology and correlated boldness behaviors in a songbird, the dark-eyed junco, following its colonization of a novel urban environment. We compared elevation in corticosterone (CORT) in response to handling and flight initiation distances in birds from a recently established urban population in San Diego, California to birds from a nearby wildland population in the species' ancestral montane breeding range. We also measured CORT and exploratory behavior in birds raised from early life in a captive common garden study. We found persistent population differences for both reduced CORT responses and bolder exploratory behavior in birds from the colonist population, as well as significant negative covariation between maximum CORT and exploratory behavior. Although early developmental effects cannot be ruled out, these results suggest contemporary adaptive evolution of correlated hormonal and behavioral traits associated with colonization of an urban habitat.
Cardoso, Goncalo C.; Whittaker, Danielle J.; Campbell-Nelson, Samuel; Robertson, Kyle W.; Ketterson, Ellen D.
Novel or changing environments expose animals to diverse stressors that likely require coordinated hormonal and behavioral adaptations. Predicted adaptations to urban environments include attenuated physiological responses to stressors and bolder exploratory behaviors, but few studies to date have evaluated the impact of urban life on codivergence of these hormonal and behavioral traits in natural systems. Here, we demonstrate rapid adaptive shifts in both stress physiology and correlated boldness behaviors in a songbird, the dark-eyed junco, following its colonization of a novel urban environment. We compared elevation in corticosterone (CORT) in response to handling and flight initiation distances in birds from a recently established urban population in San Diego, California to birds from a nearby wildland population in the species' ancestral montane breeding range. We also measured CORT and exploratory behavior in birds raised from early life in a captive common garden study. We found persistent population differences for both reduced CORT responses and bolder exploratory behavior in birds from the colonist population, as well as significant negative covariation between maximum CORT and exploratory behavior. Although early developmental effects cannot be ruled out, these results suggest contemporary adaptive evolution of correlated hormonal and behavioral traits associated with colonization of an urban habitat. PMID:22936840
Atwell, Jonathan W; Cardoso, Gonçalo C; Whittaker, Danielle J; Campbell-Nelson, Samuel; Robertson, Kyle W; Ketterson, Ellen D
The objective of this research was to characterize the productionresponsesoflactating dairycowsduringand after short-term, moderate heat exposure, and to deter- mine whether evening (p.m.) feeding would alleviate the associated production losses. In a two-period, cross- over design, eight mature lactating cows were fed a total mixed ration at either 0830 or 2030 h. Each 15-d period consisted of a 5-d thermoneutral
K. H. Ominski; A. D. Kennedy; K. M. Wittenberg; S. A. Moshtaghi Nia
DC. Pleiotropic effects of negative energy balance in the postpartum dairy cow on splenic gene expression: repercussions for innate and adaptive immunity. Physiol Genomics 39: 28-37, 2009. First published June 30, 2009; doi:10.1152\\/physiolgenomics.90394.2008.Increased energy demands to support lactation, coupled with lowered feed intake capacity results in negative energy balance (NEB) and is typically characterized by extensive mobilization of body energy
D. G. Morris; S. M. Waters; S. D. McCarthy; J. Patton; B. Earley; R. Fitzpatrick; J. J. Murphy; M. G. Diskin; D. A. Kenny; A. Brass; D. C. Wathes
|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
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); Amelia Buben (University of Washington Arts and Sciences); Caitlin C Burke (University of Washington Arts and Sciences); Nels D Carroll (University of Washington Arts and Sciences); Brett M Cook (University of Washington Arts and Sciences); Benjamin S Davis (University of Washington Arts and Sciences)
The response of Desulfovibrio vulgaris Hildenborough to salt adaptation (long-term NaCl exposure) was examined by performing physiological, global transcriptional, and metabolite analyses. Salt adaptation was reflected by increased expression of genes involved in amino acid biosynthesis and transport, electron transfer, hydrogen oxidation, and general stress responses (e.g., heat shock proteins, phage shock proteins, and oxidative stress response proteins). The expression of genes involved in carbon metabolism, cell growth, and phage structures was decreased. Transcriptome profiles of D. vulgaris responses to salt adaptation were compared with transcriptome profiles of D. vulgaris responses to salt shock (short-term NaCl exposure). Metabolite assays showed that glutamate and alanine accumulated under salt adaptation conditions, suggesting that these amino acids may be used as osmoprotectants in D. vulgaris. Addition of amino acids (glutamate, alanine, and tryptophan) or yeast extract to the growth medium relieved salt-related growth inhibition. A conceptual model that links the observed results to currently available knowledge is proposed to increase our understanding of the mechanisms of D. vulgaris adaptation to elevated NaCl levels.
He, Zhili; Zhou, Aifen; Baidoo, Edward; He, Qiang; Joachimiak, Marcin P.; Benke, Peter; Phan, Richard; Mukhopadhyay, Aindrila; Hemme, Christopher L.; Huang, Katherine; Alm, Eric J.; Fields, Matthew W.; Wall, Judy; Stahl, David; Hazen, Terry C.; Keasling, Jay D.; Arkin, Adam P.; Zhou, Jizhong
Bile salts are natural detergents that facilitate the digestion and absorption of the hydrophobic components of the diet. However, their amphiphilic nature makes them very inhibitory for bacteria and strongly influences bacterial survival in the gastrointestinal tract. Adaptation to and tolerance of bile stress is therefore crucial for the persistence of bacteria in the human colonic niche. Bifidobacterium animalis subsp. lactis, a probiotic bacterium with documented health benefits, is applied largely in fermented dairy products. In this study, the effect of bile salts on proteomes of B. animalis subsp. lactis IPLA 4549 and its bile-resistant derivative B. animalis subsp. lactis 4549dOx was analyzed, leading to the identification of proteins which may represent the targets of bile salt response and adaptation in B. animalis subsp. lactis. The comparison of the wild-type and the bile-resistant strain responses allowed us to hypothesize about the resistance mechanisms acquired by the derivative resistant strain and about the bile salt response in B. animalis subsp. lactis. In addition, significant differences in the levels of metabolic end products of the bifid shunt and in the redox status of the cells were also detected, which correlate with some differences observed between the proteomes. These results indicate that adaptation and response to bile in B. animalis subsp. lactis involve several physiological mechanisms that are jointly dedicated to reduce the deleterious impact of bile on the cell's physiology.
Sanchez, Borja; Champomier-Verges, Marie-Christine; Stuer-Lauridsen, Birgitte; Ruas-Madiedo, Patricia; Anglade, Patricia; Baraige, Fabienne; de los Reyes-Gavilan, Clara G.; Johansen, Eric; Zagorec, Monique; Margolles, Abelardo
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.
Alonso-Blanco, Carlos; Aarts, Mark G.M.; Bentsink, Leonie; Keurentjes, Joost J.B.; Reymond, Matthieu; Vreugdenhil, Dick; Koornneef, Maarten
Since any given trait of an organism is considered to represent either an adaptation to the environment or a phylogenetic constraint, most physiological gut characteristics should be adaptive in terms of optimizing digestion and utilization of the respective food source. Among the Crustacea, the taxon Oniscidea (Isopoda) is the only suborder that includes, and essentially consists of, species inhabiting terrestrial environments, feeding on food sources different from those of most other Crustacea (i.e., terrestrial leaf litter). Microelectrodes were used to assay physiological characteristics of the gut lumen from representatives of four families of terrestrial isopods: Trichoniscus pusillus (Trichoniscidae), Oniscus asellus (Oniscidae), Porcellio scaber (Porcellionidae), and Trachelipus rathkii (Trachelipodidae). Microsensor measurements of oxygen pressure (Clark-type oxygen microelectrodes) revealed that O2-consuming processes inside the gut lumen created steep radial oxygen gradients. Although all guts were oxic in the periphery, the radial center of the posterior hindgut was micro-oxic or even anoxic in the adults of the larger species. The entire gut lumen of all examined species was strongly oxidizing (Pt microelectrodes; apparent redox potential, Eh: +600-700 mV). Such conditions would allow for the coexistence of aerobic and anaerobic microorganisms, with both oxidative and fermentative activities contributing to digestion. Although bacterial O2 consumption was also observed in the midgut glands (hepatopancreas), they remained entirely oxic, probably owing to their large surface-to-volume ratio and high oxygen fluxes across the hepatopancreatic epithelium into the gland lumen. Measurements with pH microelectrodes (LIX-type) showed a slight pH gradient from acidic conditions in the anterior hindgut to neutral conditions in the posterior hindgut of O. asellus, P. scaber and T. rathkii. By contrast, the pH in the hindgut lumen of T. pusillus was almost constant. We discuss to what extent these physiological characteristics may be adaptive to the digestion of terrestrial food sources that are rich in lignocellulose. PMID:15900508
Zimmer, Martin; Brune, Andreas
Six endemic genera\\/sections of lobeliads (Campanulaceae) occupy nearly the full range of light regimes on moist sites in the Hawaiian Islands, from open alpine bogs and seacliffs to densely shaded rainforest interiors. To determine whether this clade has undergone a corresponding adaptive radiation in photosynthetic adaptations, we studied the natural light habitats and physiological characteristics of 11 species representing each
THOMAS J. GIVNISH; REBECCA A. MONTGOMERY; GUILLERMO GOLDSTEIN
The periparturient cow undergoes a transition from non-lactating to lactating at calving. The animal is tremendously challenged to maintain calcium homeostasis. Those that fail can develop milk fever, a clinical disorder that is life threatening to the cow and pre-disposes the cow to a variety of ...
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
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
The applicability of high-intensity training and the possibility of inducing physiologic adaptation to training are still uncertain in patients with severe chronic obstructive pulmonary disease (COPD). The purposes of this study were to evaluate the proportion of patients with moderate to severe COPD in whom high-intensity exercise training (30-min exercise session at 80% of baseline maximal power output [Wmax]) is feasible, and the response to training in these patients. We also sought to evaluate the possible influence of disease severity on the training intensity achieved and on the development of physiologic adaptation following endurance training. Forty-two patients with COPD (age = 66 +/- 7 yr, FEV1 = 38 +/- 13% predicted, [mean +/- SD]) were evaluated at baseline and after a 12-wk endurance training program. Each evaluation included a stepwise exercise test on an ergocycle up to the individual maximal capacity during which minute ventilation (VE), oxygen consumption (VO2), carbon dioxide production (VCO2), and arterial lactic acid concentrations were measured. The training consisted of 25 to 30-min exercise sessions on a calibrated ergocycle three times a week, with a target training intensity at 80% of Wmax. The training intensity was adjusted with the objective of reaching the target intensity, but also to ensure that the cycling exercise could be maintained for the specified duration. The training intensity sustained for the duration of each exercise session averaged 24.5 +/- 12.6, 51.7 +/- 17.4, 63.8 +/- 22.4, and 60.4 +/- 22.7% of Wmax at Weeks 2, 4, 10, and 12, respectively. High-intensity training was achieved in zero, three, five, and five patients at Weeks 2, 4, 10, and 12, respectively. A significant increase in VO2max and Wmax occurred with training (p < 0.0002). This improvement in exercise capacity was accompanied by a 6% and 17% reduction in VE and in arterial lactic acid concentration for a given work rate, respectively (p < 0.0001), suggesting that physiologic adaptation to training occurred. The intensity of training achieved, in % Wmax, was not influenced by the initial VO2max, age, or FEV1. The effects of training were compared in patients with an FEV1 > or = 40% or < 40% predicted. Percent changes in VO2max, Wmax, and VE, were significant and of similar magnitude for both groups, whereas the decrease in arterial lactic acid for a given work rate reached statistical significance only in those patients with an FEV1 > or = 40% predicted. We conclude that although most patients were unable to achieve high-intensity training as defined in this study, significant improvement in their exercise capacity was obtained and physiologic adaptation to endurance training occurred. The training intensity expressed as a percent of the individual maximum exercise capacity, and the relative effectiveness of training, were not influenced by the severity of airflow obstruction. PMID:9032194
Maltais, F; LeBlanc, P; Jobin, J; Bérubé, C; Bruneau, J; Carrier, L; Breton, M J; Falardeau, G; Belleau, R
Microbiologic cultures of fungi are routinely incubated at ambient temperatures in room air, and the rate of recovery of Aspergillus species from clinical specimens is poor. Failure of current culture methods to mimic the physiologic temperature and low-oxygen environment found in hypha-laden infected tissue may underlie this poor recovery. Experiments were performed to compare the recovery of Aspergillus spp. incubated at 35 degrees C in 6% O(2)-10% CO(2) with that at 25 degrees C in room air. The samples tested included Aspergillus-infected tissue specimens from a dog model and human autopsies, experimental anaerobically stressed Aspergillus inocula, and 10,062 consecutive clinical specimens. Culture at 35 degrees C in 6% O(2)-10% CO(2) significantly enhanced the recovery of Aspergillus spp. from the infected autopsy tissue samples. Incubation at 35 degrees C alone resulted in approximately 10-fold-improved culture recovery from the experimentally stressed hyphae, and the 6% O(2)-10% CO(2) atmosphere independently favored growth under temperature-matched conditions. Finally, incubation at 35 degrees C (in room air) improved the overall recovery of Aspergillus spp. from clinical specimens by 31%. Culture at 35 degrees C in a microaerobic atmosphere significantly enhances the recovery of Aspergillus spp. from various sources. Aspergillus hyphae growing in infected tissue appear to be adapted to the physiologic temperature and hypoxic milieu. PMID:15634998
Tarrand, Jeffrey J; Han, Xiang Y; Kontoyiannis, Dimitrios P; May, Gregory S
Changes in adipose tissue metabolism are central to adaptation of whole body energy homeostasis to pregnancy. To gain insight into the molecular mechanisms supporting tissue remodeling, we have characterized the longitudinal changes of the adipose transcriptome in human pregnancy. Healthy nonobese women recruited pregravid were followed in early (812 wk) and in late (3638 wk) pregnancy. Adipose tissue biopsies were obtained in the fasting state from the gluteal depot. The adipose transcriptome was examined via whole genome DNA microarray. Expression of immune-related genes and extracellular matrix components was measured using real-time RT-PCR. Adipose mass, adipocyte size, and cell number increased in late pregnancy compared with pregravid measurements (P < 0.001) but remained unchanged in early pregnancy. The adipose transcriptome evolved during pregnancy with 1015% of genes being differently expressed compared with pregravid. Functional gene cluster analysis revealed that the early molecular changes affected immune responses, angiogenesis, matrix remodeling, and lipid biosynthesis. Increased expression of macrophage markers (CD68, CD14, and the mannose-6 phosphate receptor) emphasized the recruitment of the immune network in both early and late pregnancy. The TLR4/NF-?B signaling pathway was enhanced specifically in relation to inflammatory adipokines and chemokines genes. We conclude that early recruitment of metabolic and immune molecular networks precedes the appearance of pregnancy-related physiological changes in adipose tissue. This biphasic pattern suggests that physiological inflammation is an early step preceding the development of insulin resistance, which peaks in late pregnancy.
Resi, Veronica; Basu, Subhabrata; Haghiac, Maricela; Presley, Larraine; Minium, Judi; Kaufman, Bram; Bernard, Steven; Catalano, Patrick
We examined the ability of a soil bacterium, Klebsiella planticola strain DSZ, to degrade the herbicide simazine (SZ). Strain DSZ is metabolically diverse and grows on a wide range of s-triazine and aromatic compounds. DSZ cells grown in liquid medium with SZ (in 10 mM ethanol) as carbon source mineralized 71.6+/-1.3% of 0.025 mM SZ with a yield of 4.6+/-0.3 microg cell dry weight mmol(-1) carbon. The metabolites produced by DSZ during SZ degradation included ammeline, cyanuric acid, N-formylurea and urea. We studied the physiological adaptations which allow strain DSZ to metabolize SZ. Using scanning electron microscopy, we detected DSZ cells covering the surfaces of SZ crystals when the herbicide was used at high concentrations (0.1 mM). The membrane order observed by FTIR spectroscopy showed membrane activity at low temperature (4 degrees C) to assimilate the herbicide. Membrane fatty acid analysis demonstrated that strain DSZ adapted to grow on SZ by increasing the degree of saturation of membrane lipid fatty acid; and the opposite effect was detected when both SZ and ethanol were used as carbon sources. This confirms the modulator effect of ethanol on membrane fluidity. PMID:15526196
Sánchez, Mariela; Garbi, Carlos; Martínez-Alvarez, Roberto; Ortiz, Luis T; Allende, José Luis; Martín, Margarita
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 1 of 4 treatments (n=8 per group, 2 groups per treatment) in a completely randomized design. Treatments were combinations of managing dairy heifers in confinement (CNF) or on pasture (PST): grazed yr 1 and 2 (PSTPST); grazed yr 1, but confined yr 2 (PSTCNF); confined yr 1 and grazed yr 2 (CNFPST); or confined yr 1 and 2 (CNFCNF). After calving, all heifers on all treatments were grazed as cows in yr 3. In yr 1, PSTPST and PSTCNF heifers were grazed for 41 d on Italian ryegrass pastures, whereas CNFPST and CNFCNF were housed in bedded-pack pens and fed a TMR. In yr 2, PSTPST and CNFPST heifers grazed Italian ryegrass pasture for 65 d, whereas PSTCNF and CNFCNF remained in confinement. In yr 2, a mid-trial assessment of heifer grazing behavior was made on PSTPST versus CNFPST heifers. Grazing activities were assessed by visual observation and heifer movement measured by portable global positioning system units. Heifers from all treatment groups subsequently calved between January and April in yr 3. All primiparous cows were then allocated to pastures by treatment group, grazed for 61 d, (May through July) in yr 3, with grazing behavior and milk production evaluated while grazing. In yr 2, heifers on the PSTPST treatment spent more time grazing than heifers on the CNFPST treatment (78 vs. 35% of the time) when first exposed to pasture (d 1). On d 1 to 3, PSTPST heifers walked a greater distance than CNFPST heifers; however, PSTPST and CNFPST heifers had similar daily grazing times and walking patterns after 3 d of pasture exposure in yr 2. As lactating cows (yr 3), cows with no (CNFCNF) grazing experience grazed less on d 1 compared with cows with (PSTPST, PSTCNF, or CNFPST) grazing experience. Day-1 grazing times in yr 3 were 62, 59, 76, and 13% of the times for cows with PSTPST, PSTCNF, CNFPST, and CNFCNF grazing experience, respectively. In yr 3, on d 1 to 3, cows with previous grazing experience as heifers (PSTPST, CNFPST, and PSTCNF) walked a greater distance than cows without previous grazing experience (CNFCNF). Milk production was lowest on d 1 to 3 for cows with no previous grazing experience (CNFCNF), but average daily milk production was not different overall over the 61 d of study in yr 3. Results indicate that grazing experiences as a heifer can affect behavior and milk production during a cow's first days on pasture. After a short acclimation period, dairy cows without grazing experience as heifers developed similar grazing behaviors and performance as cows with grazing experience as heifers. PMID:23522679
Lopes, F; Coblentz, W; Hoffman, P C; Combs, D K
Background: Improved oxygen uptake improves soccer performance as regards distance covered, involvements with the ball, and number of sprints. Large improvements in oxygen uptake have been shown using interval running. A similar physiological load arising from interval running could be obtained using the soccer ball in training. Objectives: The main aim was to study physiological adaptations to a 10 week high intensity aerobic interval training program performed by professional youth soccer players, using a soccer specific ball dribbling track. Methods: Eleven youth soccer players with a mean (SD) age of 16.9 (0.4) years performed high intensity aerobic interval training sessions twice per week for 10 weeks in addition to normal soccer training. The specific aerobic training consisted of four sets of 4 min work periods dribbling a soccer ball around a specially designed track at 9095% of maximal heart frequency, with a 3 min recovery jog at 70% of maximal heart frequency between intervals. Results: Mean Vo2max improved significantly from 63.4 (5.6) to 69.8 (6.6) ml kg1 min1, or 183.3 (13.2) to 201.5 (16.2) ml kg0.75 min1 (p<0.001). Squat jump and counter movement jump height increased significantly from 37.7 (6.2) to 40.3 (6.1) cm and 52.0 (4.0) to 53.4 (4.2) cm, respectively (p<0.05). No significant changes in body mass, running economy, rate of force development, or 10 m sprint times occurred. Conclusion: Performing high intensity 4 min intervals dribbling a soccer ball around a specially designed track together with regular soccer training is effective for improving the Vo2max of soccer players, with no negative interference effects on strength, jumping ability, and sprinting performance.
McMillan, K; Helgerud, J; Macdonald, R; Hoff, J
Part I. A series of experiments were performed to measure behavioral and blood cortisol concentration responses of cows exposed to current applied from front to rear hooves. Increased activity level was not a consistent indicator of response to current, whereas a startle response (flinch) was a consistent and repeatable indicator. Cows responded at lower current levels to the 1-front to
Douglas J. Reinemann; Morten Dam Rasmusssen; Milo C. Wiltbank; Lewis G. Sheffield; Steven D. LeMire
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...
Evolution allowed Antarctic microorganisms to grow successfully under extreme conditions (low temperature and high O2 content), through a variety of structural and physiological adjustments in their genomes and development of programmed responses to strong oxidative and nitrosative stress. The availability of genomic sequences from an increasing number of cold-adapted species is providing insights to understand the molecular mechanisms underlying crucial physiological processes in polar organisms. The genome of Pseudoalteromonas haloplanktis TAC125 contains multiple genes encoding three distinct truncated globins exhibiting the 2/2 ?-helical fold. One of these globins has been extensively characterised by spectroscopic analysis, kinetic measurements and computer simulation. The results indicate unique adaptive structural properties that enhance the overall flexibility of the protein, so that the structure appears to be resistant to pressure-induced stress. Recent results on a genomic mutant strain highlight the involvement of the cold-adapted globin in the protection against the stress induced by high O2 concentration. Moreover, the protein was shown to catalyse peroxynitrite isomerisation in vitro. In this review, we first summarise how cold temperatures affect the physiology of microorganisms and focus on the molecular mechanisms of cold adaptation revealed by recent biochemical and genetic studies. Next, since only in a very few cases the physiological role of truncated globins has been demonstrated, we also discuss the structural and functional features of the cold-adapted globin in an attempt to put into perspective what has been learnt about these proteins and their potential role in the biology of cold-adapted microorganisms. PMID:24054800
Giordano, Daniela; Coppola, Daniela; Russo, Roberta; Tinajero-Trejo, Mariana; di Prisco, Guido; Lauro, Federico; Ascenzi, Paolo; Verde, Cinzia
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.
Prat, Laure; Maillard, Julien; Grimaud, Regis; Holliger, Christof
Azospirillum brasilense is a plant growth promoting rhizobacterium (PGPR) that is being increasingly used in agriculture in a commercial scale. Recent research has elucidated key properties of A. brasilense that contribute to its ability to adapt to the rhizosphere habitat and to promote plant growth. They include synthesis of the auxin indole-3-acetic acid, nitric oxide, carotenoids, and a range of cell surface components as well as the ability to undergo phenotypic variation. Storage and utilization of polybetahydroxyalkanoate polymers are important for the shelf life of the bacteria in production of inoculants, products containing bacterial cells in a suitable carrier for agricultural use. Azospirillum brasilense is able to fix nitrogen, but despite some controversy, as judging from most systems evaluated so far, contribution of fixed nitrogen by this bacterium does not seem to play a major role in plant growth promotion. In this review, we focus on recent advances in the understanding of physiological properties of A. brasilense that are important for rhizosphere performance and successful interactions with plant roots. PMID:22092983
Fibach-Paldi, Sharon; Burdman, Saul; Okon, Yaacov
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
Visual images including intensive motions and the experience of virtual reality sometimes induce visually-indeuced motion sickness (VIMS). There are few studies that have objectively evaluated the effects of repetitive exposures to these stimuli on humans. In this study, an experiment was carried out in which the same video image was presented to human subjects three times. We evaluated changes of the intensity of VIMS they suffered from with a subjective score and a physiological index, rho(max) which is defined as the maximum cross-correlation coefficient between heart rate and pulse wave transmission time and is considered to reflect baroreflex function. The results showed that the adaptation to VIMS could be represented by a decrease in the objective index rho(max) as well as the subjective score. On the contrary, however, some subjects' rho(max) increased in a few similar time regions at every trial. This fact suggests that we can specify the part of the video image which is closely related to VIMS by analyzing the change in rho(max) with time. PMID:18001950
Sugita, Norihiro; Yoshizawa, Makoto; Abe, Makoto; Tanaka, Akira; Chiba, Shigeru; Yambe, Tomoyuki; Nitta, Shin-ichi
Ferulic acid (FRA), a phenolic compound with antioxidant and anticancer activities, naturally occurs in plants as a lignin precursor. Many veins of research have been devoted to releasing FRA from the lignin complex to improve digestibility of ruminant feeds. Thus, the objective of this research was to investigate the transfer of a given dosage of the free form of FRA into the milk of dairy cattle. Six mid- to late-lactation Holstein cows at the Cornell Research Farm (Harford, NY) were given 14-d adaptation to diet and stall position. Ad libitum access to a total mixed ration based on haylage and maize silage (31.1% neutral detergent fiber containing 5.52 mg of FRA/g) was provided during the study. A crossover design was implemented so that each cow alternated weekly between FRA-dosed and control. On d 1, jugular cannulas and urine catheters were placed in all cows. On d 2, FRA-dosed cows received a single dosage of 150 g of pure FRA powder at 0830 h via their fistula (n=4) or a balling gun for nonfistulated cows (n=2). Plasma, urine, feces, feed, orts, milk, and rumen fluid were sampled intensively for the next 36 h and analyzed for FRA concentration. On d 8, the cows crossed over and the experiment was repeated. When compared with the control, FRA administration did not have an effect on dry matter intake, milk yield, milk fat yield, milk protein yield, somatic cell count, or neutral detergent fiber content of orts and feces. The concentration of FRA in the feces did not change as a result of FRA dosage. As expected, FRA concentration increased dramatically upon FRA dosage and decreased over time until returning to basal levels in rumen fluid (4 h after dosage), plasma (5.5 h after dosage), urine (10 h after dosage), and milk (14 h after dosage). Baseline values for FRA in urine and rumen fluid were variable among cows and had an effect on FRA concentration in FRA-dosed cows. From this study, it is observed that orally ingested FRA can be transported into the milk and that the physiological transfer of FRA occurs from rumen to milk within 6.5 h or the first milking after dosage. Ferulic acid may affect the functionality of milk due to its antioxidant, anticancer, and antibacterial activities. Future research will be required to elucidate whether FRA in milk is bioavailable and bioactive, and to evaluate the complete sensory and microbiological effects of increased FRA and FRA degradation products in milk. PMID:22921626
Soberon, M A; Cherney, J H; Liu, R H; Ross, D A; Cherney, D J R
Aquaglyceroporins act as channel proteins and regulate water and glycerol exchange through cell membranes. The aquaglyceroporin aquaporin-7 (AQP7) is abundantly expressed in adipose tissue (AT) and regulates the release of glycerol produced by lipolysis. We aimed to investigate the expression of AQP7 mRNA during lactation in subcutaneous (s.c.) and visceral (v.c.) adipose depots of primiparous and pluriparous dairy cows. In 2 independent experiments, Holstein cows were supplemented with conjugated linoleic acids (CLA) or a control (CON) fat supplement at 100g/d. Pluriparous cows were supplemented starting with the first day in milk (DIM) up to 182 DIM and biopsies from s.c. AT were collected at d -21, 1, 21, 70, 105 182 196, 224, and 252 relative to calving (CLA=11; CON=10). Samples from 3s.c. and v.c. adipose depots were investigated in primiparous cows (n=25) receiving the supplements from 1 DIM until slaughter at 1, 42, or 105 DIM. The AQP7 mRNA abundance decreased from d -21 to 1 in s.c. AT of pluriparous cows without further increase to d 252 of lactation. In primiparous cows of the CON group, the AQP7 mRNA abundance increased from 1 to 105 DIM in s.c. AT from the tail head and in mesenteric AT. In retroperitoneal AT, the only depot for which a significant decrease in mass was observed with DIM, AQP7 mRNA abundance was greater at 42 and 105 than 1 DIM. Comparing the different fat depots, retroperitoneal AT had the highest and mesenterial AT had the lowest AQP7 mRNA abundance, but no general difference was observed between v.c. and s.c. fat depots. The values were not affected by CLA treatment with the exception of mesenteric AT, for which lower AQP7 mRNA abundance values were recorded in the CLA than in the CON group. The longitudinal characterization of the AQP7 mRNA expression profile throughout lactation revealed differences between primiparous and pluriparous cows, with an increase of AQP7 mRNA abundance up to 105 DIM only in the primiparous cows. Due to a lack of CLA effects in pluriparous cows and the limitation to just one fat depot in primiparous cows, a modulatory effect of CLA on AQP7 mRNA abundance in dairy cows is not supported by our study. PMID:23684044
Sauerwein, H; Saremi, B; Pappritz, J; von Soosten, D; Meyer, U; Dänicke, S; Mielenz, M
The present study was designed to evaluate the specificity of physiological adaptation to extra endurance training in five female competitive walkers and six female distance runners. The mean velocity (v) during training, corresponding to 4 mM blood lactate [onset of blood lactate accumulation (OBLA)] during treadmill incremental exercise (training v was 2.86 m.s-1, SD 0.21 in walkers and 4.02 m.s-1, SD 0.11 in runners) was added to their normal training programme and was performed for 20 min, 6 days a week for 8 weeks, and was called extra training. An additional six female distance runners performed only their normal training programme every day for about 120 min at an exercise intensity equivalent to their lactate threshold (LT) (i.e. a running v of about 3.33 m.s-1). After the extra training, there were statistically significant increases in blood lactate variables (i.e. oxygen uptake (VO2) at LT, v at LT, VO2 at OBLA, v at OBLA; P less than 0.05), and running v for 3,000 m (P less than 0.01) in the running training group. In the walking training group, there were significant increases in blood lactate variables (i.e., v at LT, v at OBLA; P less than 0.05), and walking economy. In contrast, there were no significant changes in lactate variables, running v and economy in the group of runners which carried out only the normal training programme. It is suggested that the changes in blood lactate variables such as LT and OBLA played a role in improving v of both the distance runners and the competitive walkers.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2282901
Yoshida, T; Udo, M; Chida, M; Ichioka, M; Makiguchi, K; Yamaguchi, T
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.
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
The appropriate literature has been reviewed for the purpose of defining the phenomenon of stress in lactating dairy cattle, establishing a baseline concept of lactation stress and emphasizing the most significant aspects of the natural mammary defence mechanisms. Data on the general adaptation syndrome (GAS) make it clear that stress is essentially the rate of wear and tear of the biological system affected by a stressor either eliciting stress of the organism as a whole or partly so. Owing to the variety of stressors which may affect the dairy cow at physiological and pathological levels, a definition of stress in the broad sense is indicated. This is essential from the point of view of the anti-homeostatic effects (metabolic and immunological) of lactation stress, aggravated by anti-homeostatic effects elicited by superimposed other types of stress (e.g. heat stress). The lactating cow, as a ruminant in a state of sustained stress, requires a special profile of hormonal mediators. In high yielding cows, for example, acute and sustained heat stress promotes increased activities of prolactin, progesterone and catecholamines. Compared with the mainly glycogenic/glycogenolytic metabolism of non-ruminant mammals, the lipogenic/lipolytic and glycogenic/glycogenolytic metabolism of the dairy cow depends on hormonal mediators which differ from those of the former not so much in their nature but in their magnitude and ratios. Stressors induce the development of GAS reactions in the dairy cow. These enable the cow to create and maintain homeostasis of its integrated 3 main physio-pathological systems and thus to endure the stressor(s). The cow's compensating adjustments to a stressor are therefore the effects of stress. This means that natural lactation is the effect of the lactation stress induced by the cow's progeny (i.e. the natural lactation stressor). Artificial lactation stressors (e.g. removal of milk by hand and machine) may affect the lactation stress in magnitude but not necessarily in nature. Likewise, a range of behavioural, physiological, lactational and lacteal changes related to other stressors are the effects of different types of stress. Lactation stress, like other types of stress, shows 3 stages of development, i.e., an overcompensating alarm phase (= lactogenesis), resistance phase (= galactopoiesis) and exhaustion phase (= regression). They facilitate adjustments of the cow's homeostasis from the level of involutional homeostasis (= no lactational activity) to that of lactational homeostasis. Like other tissues in a state of stress, the lactating mammary epithelium requires a greatly increased supply of glucose.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:3911132
Giesecke, W H
|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,
SIRT1 is a NAD(+)-dependent protein deacetylase that has a very large number of established protein substrates and an equally impressive list of biological functions thought to be regulated by its activity. Perhaps as notable is the remarkable number of points of conflict concerning the role of SIRT1 in biological processes. For example, evidence exists suggesting that SIRT1 is a tumor suppressor, is an oncogene, or has no effect on oncogenesis. Similarly, SIRT1 is variably reported to induce, inhibit, or have no effect on autophagy. We believe that the resolution of many conflicting results is possible by considering recent reports indicating that SIRT1 is an important hub interacting with a complex network of proteins that collectively regulate a wide variety of biological processes including cancer and autophagy. A number of the interacting proteins are themselves hubs that, like SIRT1, utilize intrinsically disordered regions for their promiscuous interactions. Many studies investigating SIRT1 function have been carried out on cell lines carrying undetermined numbers of alterations to the proteins comprising the SIRT1 network or on inbred mouse strains carrying fixed mutations affecting some of these proteins. Thus, the effects of modulating SIRT1 amount and/or activity are importantly determined by the genetic background of the cell (or the inbred strain of mice), and the effects attributed to SIRT1 are synthetic with the background of mutations and epigenetic differences between cells and organisms. Work on mice carrying alterations to the Sirt1 gene suggests that the network in which SIRT1 functions plays an important role in mediating physiological adaptation to various sources of chronic stress such as calorie restriction and calorie overload. Whether the catalytic activity of SIRT1 and the nuclear concentration of the co-factor, NAD(+), are responsible for modulating this activity remains to be determined. However, the effect of modulating SIRT1 activity must be interpreted in the context of the cell or tissue under investigation. Indeed, for SIRT1, we argue that context is everything. PMID:24020004
McBurney, Michael W; Clark-Knowles, Katherine V; Caron, Annabelle Z; Gray, Douglas A
Two studies were conducted to determine the physiological adaptations of 3 salmonid fishes to the alkaline, slightly saline waters of Pyramid Lake, NV, and their toxic effects. In the acclimation study, growth rates and blood parameters of fingerling Laho...
D. L. Koch J. Knoll J. Sommer L. Hoffman R. Knoll
To understand the mechanisms of adaptations to heterogeneous habitats along a sea coast, information is needed on the causal character of phenomena in the sequence: environmental factors » adaptive plant features » endogenous control mechanism. Abiotic conditions on the sea coast form a unique environment: sand burial, high temperature, soil salinity, soil fl ooding. Th e responses of coastal plants
For large-scale network simulations, it is often desirable to have computationally tractable, yet in a defined sense still physiologically valid neuron models. In particular, these models should be able to reproduce physiological measurements, ideally in a predictive sense, and under different input regimes in which neurons may operate in vivo. Here we present an approach to parameter estimation for a simple spiking neuron model mainly based on standard fI curves obtained from in vitro recordings. Such recordings are routinely obtained in standard protocols and assess a neurons response under a wide range of mean-input currents. Our fitting procedure makes use of closed-form expressions for the firing rate derived from an approximation to the adaptive exponential integrate-and-fire (AdEx) model. The resulting fitting process is simple and about two orders of magnitude faster compared to methods based on numerical integration of the differential equations. We probe this method on different cell types recorded from rodent prefrontal cortex. After fitting to the fI current-clamp data, the model cells are tested on completely different sets of recordings obtained by fluctuating (in vivo-like) input currents. For a wide range of different input regimes, cell types, and cortical layers, the model could predict spike times on these test traces quite accurately within the bounds of physiological reliability, although no information from these distinct test sets was used for model fitting. Further analyses delineated some of the empirical factors constraining model fitting and the models generalization performance. An even simpler adaptive LIF neuron was also examined in this context. Hence, we have developed a high-throughput model fitting procedure which is simple and fast, with good prediction performance, and which relies only on firing rate information and standard physiological data widely and easily available.
Hertag, Loreen; Hass, Joachim; Golovko, Tatiana; Durstewitz, Daniel
Prolonged exposure of Thalassiosira weissflogii (Grunow) to a sub-lethal concentration of cadmium in continuous culture resulted in the development of cellular characteristics allowing optimal growth in the presence of Cd. Examination of Cd-adapted and unadapted cells was made on steady-state populations growing at the same rate in order to eliminate any effects of differing growth rate on metabolism. Adaptation to
W. K. W. Li
BACKGROUND A diagnosis of breast cancer and treatment are psychologically stressful events, particularly over the first year after diagnosis. Women undergo many demanding and anxiety-arousing treatments such as surgery, radiation and chemotherapy. Psychosocial interventions that promote psychosocial adaptation to these challenges may modulate physiological processes (neuroendocrine and immune) that are relevant for health outcomes in breast cancer patients. METHODS Women with Stage 1 3 breast cancer recruited 4 8 weeks after surgery were randomized to either a 10-week group-based cognitive behavioral stress management (CBSM) intervention or a 1-day psychoeducational control group and completed questionnaires and late afternoon blood samples at study entry and 6 and 12 months after assignment to experimental condition. RESULTS Of 128 women initially providing psychosocial questionnaire and blood samples at study entry, 97 provided complete data for anxiety measures and cortisol analysis at all time points, and immune assays were run on a subset of 85 of these women. Those assigned to a 10-week group-based CBSM intervention evidenced better psychosocial adaptation (lower reported cancer-specific anxiety and interviewer-rated general anxiety symptoms) and physiological adaptation (lower cortisol, greater Th1 cytokine [interleukin-2 and interferon-? production and IL-2:IL-4 ratio) after their adjuvant treatment compared to those in the control group. Effects on psychosocial adaptation indicators and cortisol appeared to hold across the entire 12-month observation period. Th1 cytokine regulation changes held only over the initial 6-month period. CONCLUSIONS This intervention may have facilitated a recovery or maintenance of Th1 cytokine regulation during or after the adjuvant therapy period. Behavioral interventions that address dysregulated neuroendocrine function could play a clinically significant role in optimizing host immunologic resistance during a vulnerable period.
Antoni, Michael H.; Lechner, Suzanne; Diaz, Alain; Vargas, Sara; Holley, Heather; Phillips, Kristin; McGregor, Bonnie; Carver, Charles S.; Blomberg, Bonnie
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
Carlos Alonso-Blanco; Mark G. M. Aarts; Leonie Bentsink; Joost J. B. Keurentjes; Matthieu Reymond; Dick Vreugdenhil; M. Koornneef
Under natural drought, some physiological parameters were measured in some wild species inhabiting the western desert of Egypt. Seasonal changes of nitrogen metabolites and Na\\/K ratio were detected in the investigated species. Effect of seasons, species, and their interaction played an important role on total free amino acids, soluble proteins and Na\\/K ratio at two oases (Dakhla and Kharga). Species
A M Rayan; K A Farghali
THE group or phylobiological researches which I have carried out in the field of behaviour-disorders indicate that the neuroses and psychoses are aggravations of discrepant processes existing within society generally. In connexion with investigations of adaptive reactions, I have differentiated two internal attentional patterns1: (1) The pattern concomitant to ordinary attention in which the individual focuses upon external objects or
Summary To test the hypothesis that a smaller quantity of high intensity (HI) as opposed to a larger quantity of moderate intensity (MI) swim training would result in adaptations more specific to the short performance times of swimming competitions, two groups of elite university swimmers were tested before and after 6.5 weeks of specific HI or MI intermittent swim training. In
M. E. Houston; D. M. Wilson; H. J. Green; J. A. Thomson; D. A. Ranney
Cross-education of strength is the increase in strength of the untrained contralateral limb after unilateral training of the\\u000a opposite homologous limb. We investigated central and peripheral neural adaptations associated with cross-education of strength.\\u000a Twenty-three right-handed females were randomized into a unilateral training group or an imagery group. A sub-sample of eight\\u000a subjects (four training, four imagery) was assessed with functional
Jonathan P. Farthing; Ron Borowsky; Philip D. Chilibeck; Gord Binsted; Gordon E. Sarty
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
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.
Uzarski, Joseph S.; Scott, Edward W.; McFetridge, Peter S.
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
In response to short-term fluctuations in atmospheric CO2 concentration, ca, plants adjust leaf diffusive conductance to CO2, gc, via feedback regulation of stomatal aperture as part of a mechanism for optimizing CO2 uptake with respect to water loss. The operational range of this elaborate control mechanism is determined by the maximum diffusive conductance to CO2, gc(max), which is set by the size (S) and density (number per unit area, D) of stomata on the leaf surface. Here, we show that, in response to long-term exposure to elevated or subambient ca, plants alter gc(max) in the direction of the short-term feedback response of gc to ca via adjustment of S and D. This adaptive feedback response to ca, consistent with long-term optimization of leaf gas exchange, was observed in four species spanning a diverse taxonomic range (the lycophyte Selaginella uncinata, the fern Osmunda regalis and the angiosperms Commelina communis and Vicia faba). Furthermore, using direct observation as well as flow cytometry, we observed correlated increases in S, guard cell nucleus size and average apparent 1C DNA amount in epidermal cell nuclei with increasing ca, suggesting that stomatal and leaf adaptation to ca is linked to genome scaling.
Franks, Peter J.; Leitch, Ilia J.; Ruszala, Elizabeth M.; Hetherington, Alistair M.; Beerling, David J.
In response to short-term fluctuations in atmospheric CO(2) concentration, c(a), plants adjust leaf diffusive conductance to CO(2), g(c), via feedback regulation of stomatal aperture as part of a mechanism for optimizing CO(2) uptake with respect to water loss. The operational range of this elaborate control mechanism is determined by the maximum diffusive conductance to CO(2), g(c(max)), which is set by the size (S) and density (number per unit area, D) of stomata on the leaf surface. Here, we show that, in response to long-term exposure to elevated or subambient c(a), plants alter g(c(max)) in the direction of the short-term feedback response of g(c) to c(a) via adjustment of S and D. This adaptive feedback response to c(a), consistent with long-term optimization of leaf gas exchange, was observed in four species spanning a diverse taxonomic range (the lycophyte Selaginella uncinata, the fern Osmunda regalis and the angiosperms Commelina communis and Vicia faba). Furthermore, using direct observation as well as flow cytometry, we observed correlated increases in S, guard cell nucleus size and average apparent 1C DNA amount in epidermal cell nuclei with increasing c(a), suggesting that stomatal and leaf adaptation to c(a) is linked to genome scaling. PMID:22232765
Franks, Peter J; Leitch, Ilia J; Ruszala, Elizabeth M; Hetherington, Alistair M; Beerling, David J
The individual plant of Chinese ivy can produce three types of branches (creepy, climbing, and reproductive) during its development,\\u000a which adapt to different environmental factors. An eco-physiological model was constructed to simulate leaf net photosynthetic\\u000a rate (P\\u000a N) of Chinese ivy (Hedera nepalensis var. sinensis) in subtropical evergreen broad-leaved forest based on leaf physiological and mathematical analysis. The model integrated
J. Yang; Y.-L. Cai; S.-C. Sun; L. Wang
The purpose of this study was to evaluate fitness and health adaptations from a training program riding all-terrain vehicles (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, body composition, clinical health, and quality of life (QOL) were compared at baseline and following 6 weeks of training. In all riding groups, there were improvements in blood pressure (SBP = 9.4 ± 10.1, DBP = 5.8 ± 6.2 mmHg), fasting glucose (0.5 ± 0.7 mmol/l), subcutaneous adiposity (0.9 ± 1.1%), body mass (0.7 ± 2.7 kg), waist circumference (1.3 ± 2.5 cm), and isometric leg endurance (26 ± 44 s). All changes were of moderate to large magnitude (Cohen's d 0.52-0.94) with the exception of a small loss of body mass (Cohen's d = 0.27). Although changes occurred in the riding groups for aerobic power (2.9 ± 4.6 ml kg(-1) min(-1)), leg power (172 ± 486 w), and curl-ups (13.2 ± 22.7), these changes were not significantly different from the control group. No significant alterations occurred in resting heart rate, trunk flexibility, back endurance, hand grip strength, long jump, pull/push strength, or push-up ability as a result of training. Physical domain QOL increased in all 2 days/week riders but mental domain QOL increased in all ORM, but not ATV riders regardless of volume. Ambient carbon monoxide levels while riding (<30 ppm) were within safe exposure guidelines. Positive adaptations can be gained from a training program using off-road vehicle riding as the exercise stimulus. PMID:21225277
Burr, J F; Jamnik, V K; Gledhill, N
The degree of multiscale complexity in human behavioral regulation, such as that required for postural control, appears to decrease with advanced aging or disease. To help delineate causes and functional consequences of complexity loss, we examined the effects of visual and somatosensory impairment on the complexity of postural sway during quiet standing and its relationship to postural adaptation to cognitive dual tasking. Participants of the MOBILIZE Boston Study were classified into mutually exclusive groups: controls [intact vision and foot somatosensation, n = 299, 76 ± 5 (SD) yr old], visual impairment only (<20/40 vision, n = 81, 77 ± 4 yr old), somatosensory impairment only (inability to perceive 5.07 monofilament on plantar halluxes, n = 48, 80 ± 5 yr old), and combined impairments (n = 25, 80 ± 4 yr old). Postural sway (i.e., center-of-pressure) dynamics were assessed during quiet standing and cognitive dual tasking, and a complexity index was quantified using multiscale entropy analysis. Postural sway speed and area, which did not correlate with complexity, were also computed. During quiet standing, the complexity index (mean ± SD) was highest in controls (9.5 ± 1.2) and successively lower in the visual (9.1 ± 1.1), somatosensory (8.6 ± 1.6), and combined (7.8 ± 1.3) impairment groups (P = 0.001). Dual tasking resulted in increased sway speed and area but reduced complexity (P < 0.01). Lower complexity during quiet standing correlated with greater absolute (R = ?0.34, P = 0.002) and percent (R = ?0.45, P < 0.001) increases in postural sway speed from quiet standing to dual-tasking conditions. Sensory impairments contributed to decreased postural sway complexity, which reflected reduced adaptive capacity of the postural control system. Relatively low baseline complexity may, therefore, indicate control systems that are more vulnerable to cognitive and other stressors.
Costa, Madalena D.; Hu, Kun; Newton, Elizabeth; Starobinets, Olga; Kang, Hyun Gu; Peng, C. K.; Novak, Vera; Lipsitz, Lewis A.
The c-rings of ATP synthases consist of individual c-subunits, all of which harbor a conserved motif of repetitive glycine residues (GxGxGxG) important for tight transmembrane ?-helix packing. The c-ring stoichiometry determines the number of ions transferred during enzyme operation and has a direct impact on the ion-to-ATP ratio, a cornerstone parameter of cell bioenergetics. In the extreme alkaliphile Bacillus pseudofirmus OF4, the glycine motif is replaced by AxAxAxA. We performed a structural study on two mutants with alanine-to-glycine changes using atomic force microscopy and X-ray crystallography, and found that mutants form smaller c12 rings compared with the WT c13. The molar growth yields of B. pseudofirmus OF4 cells on malate further revealed that the c12 mutants have a considerably reduced capacity to grow on limiting malate at high pH. Our results demonstrate that the mutant ATP synthases with either c12 or c13 can support ATP synthesis, and also underscore the critical importance of an alanine motif with c13 ring stoichiometry for optimal growth at pH >10. The data indicate a direct connection between the precisely adapted ATP synthase c-ring stoichiometry and its ion-to-ATP ratio on cell physiology, and also demonstrate the bioenergetic challenges and evolutionary adaptation strategies of extremophiles.
Preiss, Laura; Klyszejko, Adriana L.; Hicks, David B.; Liu, Jun; Fackelmayer, Oliver J.; Yildiz, Ozkan; Krulwich, Terry A.; Meier, Thomas
The c-rings of ATP synthases consist of individual c-subunits, all of which harbor a conserved motif of repetitive glycine residues (GxGxGxG) important for tight transmembrane ?-helix packing. The c-ring stoichiometry determines the number of ions transferred during enzyme operation and has a direct impact on the ion-to-ATP ratio, a cornerstone parameter of cell bioenergetics. In the extreme alkaliphile Bacillus pseudofirmus OF4, the glycine motif is replaced by AxAxAxA. We performed a structural study on two mutants with alanine-to-glycine changes using atomic force microscopy and X-ray crystallography, and found that mutants form smaller c12 rings compared with the WT c13. The molar growth yields of B. pseudofirmus OF4 cells on malate further revealed that the c12 mutants have a considerably reduced capacity to grow on limiting malate at high pH. Our results demonstrate that the mutant ATP synthases with either c12 or c13 can support ATP synthesis, and also underscore the critical importance of an alanine motif with c13 ring stoichiometry for optimal growth at pH >10. The data indicate a direct connection between the precisely adapted ATP synthase c-ring stoichiometry and its ion-to-ATP ratio on cell physiology, and also demonstrate the bioenergetic challenges and evolutionary adaptation strategies of extremophiles. PMID:23613590
Preiss, Laura; Klyszejko, Adriana L; Hicks, David B; Liu, Jun; Fackelmayer, Oliver J; Yildiz, Özkan; Krulwich, Terry A; Meier, Thomas
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 105days 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 17:00-23:00h. 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±0.18h. 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
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.
Ghosh, Kaustabh; Pan, Zhi; Guan, E; Ge, Shouren; Liu, Yajie; Nakamura, Toshio; Ren, Xiang-Dong; Rafailovich, Miriam; Clark, Richard A.F.
Dissolved oxygen at four times normal saturation inhibited growth and metabolism of summer planktobacteria in surface waters of alpine oligotrophic Mountain Lake (Giles County, Virginia). Data included viable colony counts, D-(U-/sup 14/C)glucose incorporation into extractable lipid of colonies, and respiration-assimilation of D-(U-/sup 14/C)glucose by lake water samples. Significant differences were not detected in either colony counts or /sup 14/C-lipid when superoxide dismutase or catalase were added to the medium. The upper waters of Lake Hoare, Antarctica, contain dissolved oxygen at greater than or equal to42 mg liter/sup -1/ (=HDO). HDO did inhibit D-(U-/sup 14/C)glucoses assimilation-respiration compared with normal atmospheric dissolved oxygen (=ADO) in Lake Hoare water. D-(U-/sup 14/C)glucose was assimilated and respired optimally at 12/sup 0/C in Lake Hoare. Colony formation was inhibited in both lakes. Five microbial isolated were selected from Lake Hoare by growth under very high oxygen. Isolates were examined for physiological characteristics which might enhance their survival in the HDO environment. Bacterial isolates were motile Gram negative rods, catalase and oxidase positive, differing in their growth response to temperature and nutrient concentration. Four of five bacterial isolates demonstrated HDO inducible superoxide dismutase (SOD). Microorganisms in the high oxygen Lake Hoare waters may be protected from oxygen toxicity by the lake's oligotrophic nature as well as a combination of cellular defenses.
Mikell, A.T. Jr.
Anabaena spiroides has the ability to maintain intense biomass production for extensive periods in the epilimnion of a small eutrophic lake characterized by conditions shown to cause photooxidative death in a number of other phytoplankton. By the enhancement of carotenoid synthesis chlorophyll a was protected from photooxidation and prevented from catalyzing other photooxidative reactions within the cells. By temporally separating CO2 and N2 fixation, maximum utilization of photosynthetically active radiation was achieved. Because CO2 fixation was more sensitive than N2 fixation to a high oxygen concentration, the former was maximized during morning hours, before the afternoon buildup of dissolved oxygen. The diurnal partitioning of carbon and N2 fixation has two additional advantages; possible competition for reductant-generating compounds is minimized, and adequate endogenous pools of carbon skeletons are assured to accept newly fixed ammonia. Hence, Anabaena, far from undergoing photooxidative death, appears to utilize a physiological strategy which allows optimization of radiant energy use for reductive processes and dominance of surface waters and shading of deeper phytoplankton during summer blooms.
Kellar, Penelope E.; Paerl, Hans W.
Scleractinian corals hosting endosymbiotic algae (zooxanthellae) occur over a wide depth range within the photic zone of coral reefs. While some corals occur within a very narrow range others can be found over the whole reef slope. Within the genus Madracis we compared the skeletal 13C and 18O of three species that are very distinct in their distributional depth range. The species M. pharensis occurs over a wide range between 5 and > 60 m depth, while M. mirabilis and M. formosa are restricted to a narrow range growing shallow (<20 m) or deep (> 40 m), respectively. We hypothesize, that the distinct distributional depth range of the three species is due to physiological adaptation to the respective light regimes, and that this species specific adaptation must be reflected in the skeletal 18O and 13C signals. Skeletal isotope fractionation is controlled by kinetic (both 13C and 18O ) and metabolic (13C only) isotope effects. Apart from environmental factors (temperature and salinity), the calcification rate and P:R ratio control isotope fractionation. This means, that (1) the efficiency with which corals under various light regimes photosynthesize and calcify and (2) the linkage between photosynthesis and calcification become apparent when applying skeletal 13C versus 18O of the 3 Madracis species according to the model of McConnaughey (Geochim. Cosmochim. Acta, 53: 151-162, 1989). Comparing e.g. 13C vs. 18O ratios of M. pharensis (broad depth range) and M. formosa (narrow range, deep) sampled at 50 m depth, stable isotopes of M. pharensis plot on the kinetic line, while the isotopes of the deep adapted M. formosa are offset from the kinetic line. This indicates, that M. pharensis is hardly growing and is hence at its distributional depth limit, while M. formosa has even in 50 m depth a positive P:R ratio and skeletal growth. Therefore, the ratio of 13C and 18O might be useful as `proxy' in coral physiology and ecology. Vice versa an ecological approach in questions of isotope fractionation can contribute to the understanding of the coupled processes of coral metabolism and skeletogenesis.
Maier, C.; Bak, R. P. M.
Rhodococcus jostii RHA1 is a catabolically versatile soil actinomycete that can utilize a wide range of organic compounds as growth substrates including steroids. To globally assess the adaptation of the protein composition in the membrane fraction to steroids, the membrane proteomes of RHA1 grown on each of cholesterol and cholate were compared to pyruvate-grown cells using gel-free SIMPLE-MudPIT technology. Label-free quantification by spectral counting revealed 59 significantly regulated proteins, many of them present only during growth on steroids. Cholesterol and cholate induced distinct sets of steroid-degrading enzymes encoded by paralogous gene clusters, consistent with transcriptomic studies. CamM and CamABCD, two systems that take up cholate metabolites, were found exclusively in cholate-grown cells. Similarly, 9 of the 10 Mce4 proteins of the cholesterol uptake system were found uniquely in cholesterol-grown cells. Bioinformatic tools were used to construct a model of Mce4 transporter within the RHA1 cell envelope. Finally, comparison of the membrane and cytoplasm proteomes indicated that several steroid-degrading enzymes are membrane-associated. The implications for the degradation of steroids by actinomycetes, including cholesterol by the pathogen Mycobacterium tuberculosis , are discussed. PMID:23360181
Haußmann, Ute; Wolters, Dirk A; Fränzel, Benjamin; Eltis, Lindsay D; Poetsch, Ansgar
With Yangling, Yongshou, Fuxian, Ansai, Mizhi and Shenmu, the s ix counties from the south to the north in the Loess Plateau as study sites, this paper studied thoe photosynthetic charac teristics and leaf traits of Pinus tabulaeformis and Robinia pseudoacacia. The results showed that among the six sites, there were significant differences in the photosynthetic rate (Pn), photosynthetic nitrogen use efficiency (PNUE), water use efficiency (WUE), leaf mass per area (LMA), nitrogen content (Nmass), and chlorophyll content (Chl) of P. tabulaeformis and R. pseudoacacia, suggesting that the photosynthetic capacity and leaf traits of the two species differed with sites. From the south to the north, the Pn, PNUE and WUE of P. tabulaeformis increased slightly while those of R. pseudoacacia decreased significantly, indicating that in drought habitat, P. tabulaef6rmis could still maintain high photosynthetic capacity, hut the photosynthetic capacity of R. pseudoacacia was greatly restrained. Also from the south to the north, the LMA of P. tabulaeformis and R. pseudoacacia had a slight increasing trend, while Nmass and Chl decreased slightly. The variation ranges of the three parameters were greater for R. pseudoacacia than for P. tabulaeformis, indicating that P. tabulaeformis had stronger drought-tolerant capability than R. pseudoacacia, which was not only exhibited in physiological metabolism, but also in leaf morphological acclimation. The correlation analysis between photosynthetic parameters and leaf traits of P. tabulaeformis and R. pseudoacacia in the six sites showed that there was a significant negative correlation between LMA and Nmass. The Pn and PNUE of both test species had no correlations with LMA and Nmass, but had significant positive correlation with Chl. The WUE of the species was negatively correlated with LMA, but positively correlated with Nmass. PMID:17396493
Zheng, Shu-xia; Shangguan, Zhou-ping
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.
Macrobrachium rosenbergii (de Man) is an important commercial species whose larvae develop through several stages in brackish water, after which they metamorphose and the postlarvae migrate into fresh water. Modelling the multiple factor interactions which may affect the ontogeny of physiological adaptation during larval development provides an opportunity to evaluate Alderdice's concept (Alderdice, D.F., 1972. Factor combinations: responses of marine
John B. R Agard
Endocrines, the chief components of chemical centers which produce hormones in tune with intrinsic and extrinsic clues, create a chemical bridge between the organism and the environment. In fishes also hormones integrate and modulate many physiologic functions and its synthesis, release, biological actions and metabolic clearance are well regulated. Consequently, thyroid hormones (THs) and cortisol, the products of thyroid and interrenal axes, have been identified for their common integrative actions on metabolic and osmotic functions in fish. On the other hand, many anthropogenic chemical substances, popularly known as endocrine disrupting chemicals, have been shown to disrupt the hormone-receptor signaling pathways in a number fish species. These chemicals which are known for their ability to induce endocrine disruption particularly on thyroid and interrenals can cause malfunction or maladaptation of many vital processes which are involved in the development, growth and reproduction in fish. On the contrary, evidence is presented that the endocrine interrupting agents (EIAs) can cause interruption of thyroid and interrenals, resulting in physiologic compensatory mechanisms which can be adaptive, though such hormonal interactions are less recognized in fishes. The EIAs of physical, chemical and biological origins can specifically interrupt and modify the hormonal interactions between THs and cortisol, resulting in specific patterns of inter-hormonal interference. The physiologic analysis of these inter-hormonal interruptions during acclimation and post-acclimation to intrinsic or extrinsic EIAs reveals that combinations of anti-hormonal, pro-hormonal or stati-hormonal interference may help the fish to fine-tune their metabolic and osmotic performances as part of physiologic adaptation. This novel hypothesis on the phenomenon of inter-hormonal interference and its consequent physiologic interference during thyroid and interrenal interruption thus forms the basis of physiologic acclimation. This interfering action of TH and cortisol during hormonal interruption may subsequently promote ecological adaptation in fish as these physiologic processes ultimately favor them to survive in their hostile environment. PMID:22001502
Peter, Valsa S; Peter, M C Subhash
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
Detailed physiological studies were done to compare the influence of environmental pH and fermentation end product formation on metabolism, growth, and proton motive force in Sarcina ventriculi. The kinetics of end product formation during glucose fermentation in unbuffered batch cultures shifted from hydrogen-acetate production to ethanol production as the medium pH dropped from 7.0 to 3.3. At a constant pH of 3.0, the production of acetate ceased when the accumulation of acetate in the medium reached 40 mmol/liter. At a constant pH of 7.0, acetate production continued throughout the entire growth time course. The in vivo hydrogenase activity was much higher in cells grown at pH 7.0 than at pH 3.0. The magnitude of the proton motive force increased in relation to a decrease of the medium pH from 7.5 to 3.0. When the organism was grown at pH 3.0, the cytoplasmic pH was 4.25 and the organism was unable to exclude acetic acid or butyric acid from the cytoplasm. Addition of acetic acid, but not hydrogen or ethanol, inhibited growth and resulted in proton motive force dissipation and the accumulation of acetic acid in the cytoplasm. The results indicate that S. ventriculi is an acidophile that can continue to produce ethanol at low cytoplasmic pH values. Both the ability to shift to ethanol production and the ability to continue to ferment glucose while cytoplasmic pH values are low adapt S. ventriculi for growth at low pH.
Goodwin, S.; Zeikus, J.G.
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
Multiparous Angus × Gelbvieh (n = 155) beef cows (initial BW = 604.5 ± 4.2 kg) were used to determine the effect of prepartum fat supplementation on cow BW, BCS, reproduction, and calf birth weight, health, immunity, plasma fatty acid (FA) concentrations, and performance. Starting approximately 80 d prepartum, cows were adapted to a limit-fed (60% rolled corn:40% millet hay)
W. T. Small; S. I. Paisley; B. W. Hess; S. L. Lake; E. J. Scholljegerdes; T. A. Reed; E. L. Belden; S. Bartle
The life and operation of cells involve many physiological processes that take place over fast timescales of milliseconds to minutes. Genetically-encoded technologies for driving or suppressing specific fast physiological processes in intact cells, perhaps embedded within intact tissues in living organisms, are critical for the ability to understand how these physiological processes contribute to emergent cellular and organismal functions and behaviors. Such synthetic physiology tools are often incredibly complex molecular machines, in part because they must operate at high speeds, without causing side effects. We here explore how synthetic physiology molecules can be identified and deployed in cells, and how the physiology of these molecules in cellular contexts can be assessed and optimized. For concreteness, we discuss these methods in the context of the optogenetic light-gated ion channels and pumps that we have developed over the past few years as synthetic physiology tools, and widely disseminated for use in neuroscience for probing the role of specific brain cell types in neural computations, behaviors, and pathologies. We anticipate that some of the insights revealed here may be of general value for the field of synthetic physiology, as they raise issues that will be of importance for the development and use of high-performance, high-speed, side-effect free physiological control tools, in heterologous expression systems.
Chow, Brian Y.; Chuong, Amy S.; Klapoetke, Nathan C.; Boyden, Edward S.
The most economically relevant diseases in high yielding cows, especially during early lactation, are ketosis, hypocalcaemia and mastitis. Physiological variation of milk parameters can be identified precisely and economically by modern rapid analytical methods. The biochemical milk profile can be used as a mirror of the cow's metabolic status by investigating milk concentrations of chemicals including beta-hydroxybutyric acid, acetone, citrate,
J. Hamann; V. Krömker
The aim of this study was to investigate the supposed vertical diel migration and the accompanying physiology of Beggiatoa bacteria from hypersaline microbial mats. We combined microsensor, stable-isotope, and molecular techniques to clarify the phylogeny and physiology of the most dominant species inhabiting mats of the natural hypersaline Lake Chiprana, Spain. The most dominant morphotype had a filament diameter of
Susanne Hinck; Thomas R. Neu; Gaute Lavik; Marc Mussmann; Dirk de Beer; Henk M. Jonkers
Naturally adapted salt tolerant populations provide a valuable material for exploring the adaptive components of salt tolerance. Under this aspect, two populations of Cynodon dactylon (L.) Pers. were subjected to salt stress in hydroponics. One was collected from a heavily salt-affected soil in the vicinity of a natural salt lake, Uchhali Lake, in the Salt Range of the Punjab province
Mansoor Hameed; Muhammad Ashraf
Objectives: In order to measure the immune response evoked in breast-fed infants with cows milk allergy (CMA) by cows milk challenge through human milk, mothers were given increasing doses of cows milk after they had been on a cows milk elimination diet. Another objective was to study the secretion of ?-lactoglobulin (BLG) into human milk before and during milk challenge
Kirsi-Marjut Järvinen; Soili Mäkinen-Kiljunen; Hanna Suomalainen
In a child that is allergic to milk, the natural next step, following the elimination diet, is the reintroduction of cow's milk. Several questions may arise. When feasible, this reintroduction has many benefits for the child and his family. However, the disease needs to be well defined by physicians and explained to parents. They need to understand that there are different types of allergy to cow's milk, specifically IgE- and non-IgE-mediated, and each of these may exhibit both a variable duration and frequently an incomplete recovery. Deciding where to first reintroduce cow's milk to a child who has previously followed a milk-free diet, whether it be at home or in a hospital, also frequently presents an issue. Following this first reintroduction, the progressive increase of milk into the diet needs to be managed properly, as not all children will go back to a normal dairy products intake. Recent studies show that most children with milk allergy tolerate products containing baked milk and that their consumption might speed up recovery. Hence, the purpose of the milk challenge in a child on a milk-free diet is becoming, even in a child still reactive to milk, the first step of gradual and individually adapted reintroduction of milk or dairy products. When reintroduction of cow's milk does not work, immunotherapy becomes an option, and this is carried out in specialized centers. PMID:24112424
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
|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
Effect of rate-adaptive pacing on performance and physiological parameters during activities of daily living in the elderly: results from the CLEAR (Cylos Responds with Physiologic Rate Changes during Daily Activities) study
Aims For most elderly pacemaker patients, evaluation of rate-adaptive pacing using treadmill and bicycle tests is impractical and not representative of typical daily activities. This study was designed to compare the performance and physiological response of the closed-loop stimulation (CLS) rate-adaptive sensor to accelerometer (XL) and no rate sensor (DDD) during typical daily activity testing. Methods and results Subjects recently implanted with a Cylos pacemaker completed timed activities of daily life testing, which included walking, sweeping, and standing from a seated position. Activity performance and physiological response from each sensor mode was evaluated for subjects requiring ?80% pacing. Overall, 74 subjects needed ?80% pacing during at least one test. An increase in the area swept (CLS vs. XL, 1.67 m2 difference, P = 0.009; CLS vs. DDD, 1.59 m2 difference, P = 0.025) and a decrease in the prevalence of orthostatic hypotension (OH) after standing 1 min (CLS vs. XL, odds ratio = 0.16, P = 0.006; CLS vs. DDD, odds ratio = 0.18, P = 0.012) was observed in the CLS mode as compared with XL and DDD. No statistical difference in walk distance was observed between CLS and XL or CLS and DDD. Conclusion In acute testing, as compared with XL and DDD, CLS provides a more physiological response during the performance of activities of daily living for subjects with ?80% pacing. This is clinically reflected in better performance during the sweep test as well as a decrease in the prevalence of OH in our elderly population. Clinicaltrials.gov identifier: NCT00355797
Abi-Samra, Freddy M.; Singh, Narendra; Rosin, Benjamin L.; Dwyer, Jerome V.; Miller, Crystal D.
Discussion of a strategy for using a classic paper to enhance the studentsÃÂ 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)
An adaptive speed/flow controller was developed based on previous work using the intrinsic pump parameters. Those intrinsic parameters were measured by long-term reliable sensors. The adaptive controller was designed to track the varying total peripheral resistance and update the controller parameters correspondingly. The controller was studied in computer simulation on two different types of pumps, whose hydrodynamic characteristics are described by static and dynamic equation, respectively. The pump pressure rise of both pumps is accessible. With the designed adaptive controller, the abnormal hemodynamic values indicating congestive heart failure, including total blood flow, mean aortic pressure, left ventricular end-diastolic pressure, are all successfully restored to normal ranges. This good performance is consistent for both pumps in the variation of activities and left ventricular failure levels. The results show that the designed controller can be applicable for rotary blood pumps whose pump pressure rise can be measured or derived from pump intrinsic parameters. PMID:19506462
Current knowledge of the physiological, biomechanical, and sensory eVects of the cycle to run transition in the Olympic tria- thlon (1.5 km,10 km,40 km) is reviewed and implications for the training of junior and elite triathletes are discussed. Triathlon running elicits hyperventilation, increased heart rate, decreased pulmonary compli- ance, and exercise induced hypoxaemia. This may be due to exercise intensity,
Gregoire P Millet; Veronica E Vleck
Detailed physiological studies were done to compare the influence of environmental pH and fermentation end product formation on metabolism, growth, and proton motive force in Sarcina ventriculi. The kinetics of end product formation during glucose fermentation in unbuffered batch cultures shifted from hydrogen-acetate production to ethanol production as the medium pH dropped from 7.0 to 3.3. At a constant pH
S. Goodwin; J. G. Zeikus
Background We previously reported infectious HCV clones that contain the convenient reporters, green fluorescent protein (GFP) and Renilla luciferase (Rluc), in the NS5a-coding sequence. Although these viruses were useful in monitoring viral proliferation and screening of anti-HCV drugs, the infectivity and yield of the viruses were low. Methodology/Principal Findings In order to obtain a highly efficient HCV cultivation system, we transfected Huh7.5.1 cells  with JFH 5a-GFP RNA and then cultivated cells for 20 days. We found a highly infectious HCV clone containing two cell culture-adapted mutations. Two cell culture-adapted mutations which were responsible for the increased viral infectivity were located in E2 and p7 protein coding regions. The viral titer of the variant was ?100-fold higher than that of the parental virus. The mutation in the E2 protein increased the viability of virus at 37°C by acquiring prolonged interaction capability with a HCV receptor CD81. The wild-type and p7-mutated virus had a half-life of ?2.5 to 3 hours at 37°C. In contrast, the half-life of viruses, which contained E2 mutation singly and combination with the p7 mutation, was 5 to 6 hours at 37°C. The mutation in the p7 protein, either singly or in combination with the E2 mutation, enhanced infectious virus production about 1050-fold by facilitating an early step of virion production. Conclusion/Significance The mutation in the E2 protein generated by the culture system increases virion viability at 37°C. The adaptive mutation in the p7 protein facilitates an earlier stage of virus production, such as virus assembly and/or morphogenesis. These reporter-containing HCV viruses harboring adaptive mutations are useful in investigations of the viral life cycle and for developing anti-viral agents against HCV.
Jang, Sung Key
The American marten (Martes americana) is a boreal forest marten with low body adiposity throughout the year. The aim of this study was to investigate the adaptations\\u000a of this lean-bodied species to fasting for an ecologically relevant duration (48 h) by exposing eight farm-bred animals to\\u000a total food deprivation with seven control animals. Selected morphological and hematological parameters, plasma and serum
Petteri Nieminen; Kirsti Rouvinen-Watt; Seppo Saarela; Anne-Mari Mustonen
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
Shaffer, H Bradley; Minx, Patrick; Warren, Daniel E; Shedlock, Andrew M; Thomson, Robert C; Valenzuela, Nicole; Abramyan, John; Amemiya, Chris T; Badenhorst, Daleen; Biggar, Kyle K; Borchert, Glen M; Botka, Christopher W; Bowden, Rachel M; Braun, Edward L; Bronikowski, Anne M; Bruneau, Benoit G; Buck, Leslie T; Capel, Blanche; Castoe, Todd A; Czerwinski, Mike; Delehaunty, Kim D; Edwards, Scott V; Fronick, Catrina C; Fujita, Matthew K; Fulton, Lucinda; Graves, Tina A; Green, Richard E; Haerty, Wilfried; Hariharan, Ramkumar; Hernandez, Omar; Hillier, Ladeana W; Holloway, Alisha K; Janes, Daniel; Janzen, Fredric J; Kandoth, Cyriac; Kong, Lesheng; de Koning, Ap Jason; Li, Yang; Literman, Robert; McGaugh, Suzanne E; Mork, Lindsey; O'Laughlin, Michelle; Paitz, Ryan T; Pollock, David D; Ponting, Chris P; Radhakrishnan, Srihari; Raney, Brian J; Richman, Joy M; St John, John; Schwartz, Tonia; Sethuraman, Arun; Spinks, Phillip Q; Storey, Kenneth B; Thane, Nay; Vinar, Tomas; Zimmerman, Laura M; Warren, Wesley C; Mardis, Elaine R; Wilson, Richard K
PGC-1? is an inducible transcriptional coactivator that regulates cellular energy metabolism and adaptation to environmental and nutritional stimuli. In tissues expressing PGC-1?, alternative splicing produces a truncated protein (NT-PGC-1?) corresponding to the first 267 amino acids of PGC-1?. Brown adipose tissue also expresses two novel exon 1b-derived isoforms of PGC-1? and NT-PGC-1?, which are 4 and 13 amino acids shorter in the N termini than canonical PGC-1? and NT-PGC-1?, respectively. To evaluate the ability of NT-PGC-1? to substitute for PGC-1? and assess the isoform-specific role of NT-PGC-1?, adaptive thermogenic responses of adipose tissue were evaluated in mice lacking full-length PGC-1? (FL-PGC-1?/?) but expressing slightly shorter but functionally equivalent forms of NT-PGC-1? (NT-PGC-1?254). At room temperature, NT-PGC-1? and NT-PGC-1?254 were produced from conventional exon 1a-derived transcripts in brown adipose tissue of wild type and FL-PGC-1??/? mice, respectively. However, cold exposure shifted transcription to exon 1b, increasing exon 1b-derived mRNA levels. The resulting transcriptional responses produced comparable increases in energy expenditure and maintenance of core body temperature in WT and FL-PGC-1??/? mice. Moreover, treatment of the two genotypes with a selective ?3-adrenergic receptor agonist produced similar increases in energy expenditure, mitochondrial DNA, and reductions in adiposity. Collectively, these findings illustrate that the transcriptional and physiological responses to sympathetic input are unabridged in FL-PGC-1??/? mice, and that NT-PGC-1? is sufficient to link ?3-androgenic receptor activation to adaptive thermogenesis in adipose tissue. Furthermore, the transcriptional shift from exon 1a to 1b supports isoform-specific roles for NT-PGC-1? in basal and adaptive thermogenesis.
Chang, Ji Suk; Fernand, Vivian; Zhang, Yubin; Shin, Jeho; Jun, Hee-Jin; Joshi, Yagini; Gettys, Thomas W.
Three lipid-dependent Malassezia isolates (here named 114A, 114B and 114C) recovered from a dog with skin lesions were phenotypically and genotypically characterized. All presented ovoid cells and buds formed on a narrow base. Most of the results from physiological tests were consistent with those of Malassezia furfur. The phylogenetic analysis of ITS-1 and LSU nucleotide sequences was concordant in placing all three clinical Malassezia isolates close to M. furfur. However, the phylogenetic data on the chs-2 sequence revealed that clinical isolate 114A is distinct from M. furfur and was closely affiliated to the sequence of M. pachydermatis with high nodal support. In particular, lipid-dependent isolates 114A displayed chs-2 sequences similar (100%) to that of the non-lipid dependent species Malassezia pachydermatis. The presence of the genetic and physiological polymorphisms detected in these three isolates of M. furfur could have resulted from a process of adaptation of this anthropophilic species to a new host. PMID:21070187
Cafarchia, C; Latrofa, M S; Figueredo, L A; da Silva Machado, M L; Ferreiro, L; Guillot, J; Boekhout, T; Otranto, D
The COW, or Console On Wheels, is the primary operator interface to the SLC accelerator control system. A hardware and software description of the COW, a microcomputer based system with a color graphics display output and touchpanel and knob inputs, is given. The ease of development and expandability, due to both the modular nature of the hardware and the multitasking, interrupt driven software running in the COW, are described. Integration of the COW into the SLCNET communications network and SLC Control system is detailed.
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.
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; Leinwand, Leslie A
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.
Wall, Christopher E.; Cozza, Steven; Riquelme, Cecilia A.; McCombie, W. Richard; Heimiller, Joseph K.; Marr, Thomas G.
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 (T(3)), thyroxin (T(4)), and cortisol. However, walking stress did not influence the reproductive hormone levels. The significant changes in RR, RT, plasma cortisol, T(3) and T(4) 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. PMID:21455731
Sejian, Veerasamy; Maurya, Vijai P; Naqvi, Syed M K
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.
Increased hair cortisol concentrations have been associated with stress exposure in both human and nonhuman primates, and hair cortisol is now gaining attention as a biomarker for stress-related health problems. The present study examined the behavioral and physiological reactions of rhesus monkey (Macaca mulatta) infants reared in three different rearing environments to the major stressor of relocation. Infant monkeys (n=61) were studied from birth through 2 years of age. For the first 8 months of life, infants were either with their mothers and peers (MPR, n=21) or reared in a nursery using either peer-rearing (PR, n=20) or surrogate-peer-rearing (SPR, n=20). At approximately 8 months of age, infants were removed from their rearing group, simultaneously placed into a large social environment consisting of infants from all three rearing conditions, and observed for the next 16 months. Behavior was recorded twice per week from 1 to 24 months, and composite anxiety scores were calculated for each monkey. Monkeys were initially shaved at the nape of the neck on day 14 to remove any prenatal effects on hair cortisol deposition. Hair samples were then collected by re-shaving at 6, 12, 18 and 24 months and analyzed for cortisol content. MPR monkeys were the least affected by the stressor, showing smaller increases in anxious behavior than the other groups and more rapid physiological adaptation as assessed using hair cortisol. PR monkeys showed heightened and prolonged anxious behavior, had the highest cortisol levels prior to relocation, and their cortisol levels did not decline until more than a year later. SPR monkeys exhibited more rapid behavioral adaptation than PR monkeys, showing heightened but not prolonged anxious behavior. However, the SPR group showed a marked increase in cortisol in response to the relocation, and like the PR group, their physiological adaptation was slower than that of the MPR group as indicated by elevated cortisol levels at 18 months. By 24 months of age (16 months after relocation), all rearing groups were indistinguishable from one another physiologically and behaviorally. Spearman rank correlation revealed that hair cortisol taken at month 6 was not correlated with composite anxiety scores from months 6 to 8 (just before the relocation), but was positively correlated with composite anxiety scores between months 8 and 12 (immediately after relocation) for PR infants only (r(s)=0.75, p<0.001). Month 6-hair cortisol tended to positively correlate with composite anxiety scores for the following 6 months (months 12-18) for PR monkeys only (r(s)=0.47, p=0.037), which exhibited more anxious behavior than MPR and SPR infants during this period (ANOVA: F((2,60))=14.761, p<0.001) This is the first study to show that elevated hair cortisol early in life is a biomarker for the later development of anxious behavior in response to a major life stressor, particularly for infant monkeys exposed to early life adversity in the form of peer-rearing. PMID:21715101
Dettmer, Amanda M; Novak, Melinda A; Suomi, Stephen J; Meyer, Jerrold S
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 chronic terrestrial exercise (TEx) and microgravity (?G). We used a series of peer-reviewed publications to demonstrate that many of the physiological adaptations to TEx and ?G are opposite. For example, TEx typically improves cardiovascular function and orthostatic tolerance, whereas ?G can lead to declines in both. TEx leads to muscle hypertrophy, and ?G elicits muscle atrophy. TEx increases bone mineral density and red blood cell mass, whereas ?G decreases bone mineral density and red blood cell mass. Importantly, exercise during spaceflight remains a crucial countermeasure to limit some of these adverse physiological adaptations to ?G. This curriculum develops critical thinking skills by dissecting peer-reviewed articles and discussing the strengths and weaknesses associated with simulated and actual ?G studies. Moreover, the curriculum includes studies on both animals and humans, providing a strong translational component to the curriculum. In summary, we have developed a novel space physiology curriculum delivered during the final weeks of an exercise physiology course in which students gain critical new knowledge that reinforces key concepts presented throughout the semester. PMID:24022767
Carter, Jason R; West, John B
Bacteria on meat are subjected to specific living conditions that differ drastically from typical laboratory procedures in synthetic media. This study was undertaken to determine the behavior of bacteria when transferred from a rich-liquid medium to solid matrices, as is the case during microbial process validation. Escherichia coli cultured in Brain-Heart Infusion (BHI) broth to different growth phases were inoculated in ground beef (GB) and stored at 5°C for 12 days or spread onto BHI agar and cooked meat medium (CMM), and incubated at 37°C for several hours. We monitored cell densities and the expression of ? factors and genes under their control over time. The initial growth phase of the inoculum influenced growth resumption after transfer onto BHI agar and CMM. Whatever the solid matrix, bacteria adapted to their new environment and did not perceive stress immediately after inoculation. During this period, the ?(E) and ?(H) regulons were not activated and rpoD mRNA levels adjusted quickly. The rpoS and gadA mRNA levels did not increase after inoculation on solid surfaces and displayed normal growth-dependent modifications. After transfer onto GB, dnaK and groEL gene expression was affected more by the low temperature than by the composition of a meat environment. PMID:22850375
Guernec, Anthony; Robichaud-Rincon, Philippe; Saucier, Linda
With the evolution of exercise science a vast amount of information concerning the physiological effects of training has been generated. Understanding the basic training responses and adaptations of various modes of conditioning can give the clinician ins...
W. J. Kraemer W. L. Daniels
Sale of cull cows accounts for 15-25 % of yearly gross revenues of cow-calf operations in the United States. Yet many beef producers view market cows as culls rather than an important source of beef for the food industry and therefore may overlook opportunities to add value to market cows, and ther...
Objectives were to develop a system to administer exercise training to dairy cows, to measure potential physiological indicators of fitness, and to assess physi- cal fitness. Nonlactating, nonpregnant multiparous Holstein cows (n = 19) were in one of three exercise training treatments: no exercise; 1-h exercise; or 2-h exercise by walking 3 km\\/h every other day for 60 d in
J. A. Davidson; D. K. Beede
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.
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.
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.
Duran-Pasten, Maria Luisa; Fiordelisio, Tatiana
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 tissues adaptations to physiological state or nutrition.
Bionaz, Massimo; Loor, Juan J.
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.
Voss, Bjorn; Bolhuis, Henk; Fewer, David P.; Kopf, Matthias; Moke, 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.
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
Goat milk and cow milk are commonly used in infant formula preparations and, as such, understanding the nutritional characteristics of infant formulas made from these milks is important. In this study, a goat milk infant formula was compared with an adapted (whey-enhanced) cow milk infant formula with respect to mineral absorption and deposition using the 3-wk- old piglet as a
S. M. Rutherfurd; A. J. Darragh; W. H. Hendriks; C. G. Prosser; D. Lowry
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
Contents: Cold Acclimation in Arctic Lemmings; Tolerance of Arctic Lemmings to Hypothermia and Dehydration; Renal Function in Hypothermic Arctic Lemmings; Cold Acclimation in the Tundra Vole (Microtus oeconomus); Induction of Summer Hibernation in the 13-...
G. E. Folk M. A. Folk J. J. Berberich J. J. Minor K. Magoon
During this study we explored the gait attributes commonly used in subjective locomotion scoring systems and use new technology to evaluate these gait attributes objectively on 60 Holstein lactating dairy cattle. Kinematic gait analysis more commonly used in sports and equine science was adapted for use on dairy cattle to assess stride characteristics, joint flexion, and spine posture in dairy cows with different lameness status. Cows that were lame had shorter stride length and had negative tracking distance compared with nonlame cattle. Lame cattle did not show any difference in spine posture when walking. Gait alterations were more evident in cows with sole ulcers, which showed considerable shortening of stride and had more negative tracking compared with cows with no hoof lesions. Cows with sole ulcers also showed significant shortening of the spine when walking than cows with no hoof lesions. PMID:23548277
Blackie, N; Bleach, E C L; Amory, J R; Scaife, J R
The adaptation of bulls used for natural breeding purposes to the Gulf Coast region of the United States including all of Florida is an important topic. Nearly 40% of the U.S. cow/calf population resides in the Gulf Coast and Southeast. Thus, as A.I. is relatively rare, the number of bulls used for ...
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
Many physiological processes of domestic animals exhibit daily rhythmicity. The goal of the present study was to investigate, in cows, the influence of different schedules of feeding on daily rhythms of blood urea and ammonia concentrations. Fifteen Italian Brown cows, from the same farm, clinically healthy and placed at the same environmental temperature and photoperiod, were used for this study.
Giuseppe Piccione; Fortunata Grasso; Francesco Fazio; Anna Assenza; Giovanni Caola
The aim of this study was to investigate whether the prevention of suckling and the separation from a foster cow in two steps lower the behavioural and physiological stress reaction in calves compared with if the two events occur simultaneously. Twelve groups, each consisting of one cow and four calves, were formed when the calves were 1 week old, and
Jenny M. Loberg; Carlos E. Hernandez; Tomas Thierfelder; Margit B. Jensen; Charlotte Berg; Lena Lidfors
Twelve Brown Swiss (BS) and 12 Peruvian Criollo cows (CR, a local Peruvian cow type adapted to altitude and harsh environment), both Bos taurus and adapted to altitudes >3500 m a.s.l. (above sea level), were kept at 200 and 3600 m a.s.l. and assigned to three dietary treatments, respectively. The experimental design was a 2 (cow types)×3 (diets)×2 (sites) factorial arrangement (total
K. Bartl; C. A. Gómez; T. Aufdermauer; M. Garcia; M. Kreuzer; H. D. Hess; H.-R. Wettstein
Variation exists among cattle populations to improve the conversion of feed resources to a final product. A biologically efficient cow is one producing a calf each year she remains in the cowherd. The nutrition-reproduction axis may influence this success. Energy expenditure for maintenance may ef...
Consider a Spherical Cow describes relatively simple mathematical methods for developing quantitative answers to often complex environmental problems. Early chapters provide systematic insights into problem solving and identifying mathematical tools and models that lead to back of the envelope answers. Subsequent chapters treat increasingly complex problems. Solutions are sought at different levels, e.g., informed guesses, quantitative solutions based on detailed
The pregnant patient in the intensive care unit (ICU) poses many challenges. Physicians and nurses need to understand the basic concepts of maternal physiology and fetal physiology. The physicians must care for the mother and consider the potential adverse effects that diagnostic and therapeutic interventions might have on the fetus. This article focuses primarily on the normal pregnant state with appropriate references to how pregnancy may affect the patient in specific circumstances relating to the ICU. The physiologic adaptation of the major organs to the pregnant state should be familiar to ICU physicians. PMID:15388191
Chesnutt, Asha N
Dairy producers must overcome substantial challenges to achieve milk outputs > 14,000 kg of milk/yr per cow within the next decade. To obtain high productivity, a more complete comprehension of the dynamics of metabolism, nutrient utilization, and nutrient absorption will enable better prediction of the efficiency of utilization of these nutrients. A better understanding of the dynamics of rumen function and a more accurate prediction of nutrient flow from the rumen are necessary. Grouping strategy and group feeding behavior influence cow productivity and farm profitability. Understanding of the variance of individual cow responses to management practice is critical. Feeding system design and management and diet formulation techniques need to be developed that recognize the dynamic nature of cow physiology and the variability in feedstuffs and cow requirements. These concepts need to be integrated into total farm management and require the use of new computer modeling technologies. PMID:8227638
Sniffen, C J; Beverly, R W; Mooney, C S; Roe, M B; Skidmore, A L; Black, J R
Effects of chop length (shorter = 10 mm or longer = 19mm)ofalfalfasilageandcornsilageweredetermined in 16 midlactation Holstein cows using a 4 × 4 Latin square design with a 2 × 2 arrangement of treatments. Experimental periods were 21 d long and consisted of 14 d of adaptation and 7 d of sampling. Cows received total mixed ration containing (dry matter basis)
S. K. Bhandari; K. H. Ominski; K. M. Wittenberg; J. C. Plaizier
To determine the maternal and reproductive performance of adapted F1 cows in the subtropics, 42 Brahman x Angus, 34 Senepol x Angus, and 50 Tuli x Angus cows were bred to Angus bulls to calve first and subsequently to Charolais bulls to calve as three- to eight-yr-olds. Age at first calving did not...
Twice-daily milking is the most common milking regimen used globally. A reduction in milking frequency to once daily, combined with a reduced feed allowance (FA), could reduce the physiological stress associated with the transition to peak milk production, and hence improve immune function. This study investigated how milking frequency and FA affect dairy cow immune status. Cows (n = 48) were milked once a day (OAD) or twice a day (TAD) on 1 of 2 FA: high (HFA) or low (LFA), in a 2 × 2 factorial arrangement of treatments. After the mean calving date of March 11, HFA cows were offered ad libitum grass silage and 7 kg of concentrates/cow per day until March 22, then 4 kg of concentrates/cow per day until April 17, and thereafter allocated 31.3 kg of dry matter (DM) grass/cow per day. The LFA cows were offered 4 kg of concentrates/cow per day, 1 kg of concentrates/cow per day, and allocated 19 kg of DM grass/cow per day for the same respective periods. Milk yield was recorded daily and body condition score weekly, and somatic cell count was performed at approximately 2-wk intervals. Blood samples were collected prepartum (d -7 to -1) and at d 1 to 7, d 14 to 21, and d 42 to 49 postpartum. Total and differential leukocyte percentage, IFN-? production in response to concanavalin A and phytohemagglutinin, and cortisol, haptoglobin (Hp), and serum amyloid A (SAA) concentrations were evaluated. Cows milked OAD had reduced milk yield and body reserve mobilization, but higher somatic cell counts. Milking frequency and diet had no effect on total leukocyte counts. Cows milked OAD had a higher lymphocyte percentage and lower monocyte percentage, and tended to have a lower neutrophil percentage than cows milked TAD. In addition, the LFA cows had a higher eosinophil percentage than cows fed the HFA. Milking frequency and diet had no effect on IFN-?, Hp, SAA, or cortisol production. Utilization of strategies to reduce milk yield at the beginning of the lactation could not only reduce body reserve mobilization, but also help to maintain a functioning immune system, and thus improve cow welfare. PMID:22365202
O'Driscoll, K; Olmos, G; Llamas Moya, S; Mee, J F; Earley, B; Gleeson, D; O'Brien, B; Boyle, L
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
Background: The efficacy of emotional disclosure in alleviating psychological and physical stress has been well documented in controlled laboratory studies. A next step is to evaluate its clinical utility in real world settings. We adapted the emotional disclosure intervention for use in home-based settings by stimulating the suggested effective ingredients of cognitive-emotional processing, and evaluated its psychological and clinical effectiveness.
Henriët van Middendorp; Rinie Geenen; Marjolijn J. Sorbi; Lorenz J. P. van Doornen; Johannes W. J. Bijlsma
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
It appears that the physiological and biochemical adaptation of skeletal muscle to training in equine species shows a lot of similarities with human and rodent physiological adaptation. On the other hand it is becoming increasingly clear that intra-cellular mechanisms of adaptation (substrate transport, enzyme activity, etc) differ considerably between species. The major drawbacks in equine training physiological research are the
K. G. van Dam
Anthropogenic water pollution is producing a challenge to the survival of phytoplankton populations. From an ecological point\\u000a of view, the tolerance of these microorganisms to water pollution is of paramount importance since they are the principal\\u000a primary producers of aquatic ecosystems. The adaptation of a common chlorophyta species (Scenedesmus intermedius) exposed to selected dose-response chloramphenicol (CAP) concentrations has been analyzed.
S. Sánchez-Fortún; F. Marvá; M. Rouco; E. Costas; V. López-Rodas
The central pattern generators (CPGs) in the spinal cord strongly contribute to locomotor behavior. To achieve adaptive locomotion,\\u000a locomotor rhythm generated by the CPGs is suggested to be functionally modulated by phase resetting based on sensory afferent\\u000a or perturbations. Although phase resetting has been investigated during fictive locomotion in cats, its functional roles in\\u000a actual locomotion have not been clarified.
Shinya Aoi; Naomichi Ogihara; Tetsuro Funato; Yasuhiro Sugimoto; Kazuo Tsuchiya
Adapting to the lactating state requires metabolic adjustments in multiple tissues, especially in the dairy cow, which must meet glucose demands that can exceed 5 kg/day in the face of negligible gastrointestinal glucose absorption. These challenges are met through the process of homeorhesis, the alteration of metabolic setpoints to adapt to a shift in physiological state. To investigate the role of inflammation-associated pathways in these homeorhetic adaptations, we treated cows with the nonsteroidal anti-inflammatory drug sodium salicylate (SS) for the first 7 days of lactation. Administration of SS decreased liver TNF-? mRNA and marginally decreased plasma TNF-? concentration, but plasma eicosanoids and liver NF-?B activity were unaltered during treatment. Despite the mild impact on these inflammatory markers, SS clearly altered metabolic function. Plasma glucose concentration was decreased by SS, but this was not explained by a shift in hepatic gluconeogenic gene expression or by altered milk lactose secretion. Insulin concentrations decreased in SS-treated cows on day 7 compared with controls, which was consistent with the decline in plasma glucose concentration. The revised quantitative insulin sensitivity check index (RQUICKI) was then used to assess whether altered insulin sensitivity may have influenced glucose utilization rate with SS. The RQUICKI estimate of insulin sensitivity was significantly elevated by SS on day 7, coincident with the decline in plasma glucose concentration. Salicylate prevented postpartum insulin resistance, likely causing excessive glucose utilization in peripheral tissues and hypoglycemia. These results represent the first evidence that inflammation-associated pathways are involved in homeorhetic adaptations to lactation.
Farney, Jaymelynn K.; Mamedova, Laman K.; Coetzee, Johann F.; KuKanich, Butch; Sordillo, Lorraine M.; Stoakes, Sara K.; Minton, J. Ernest; Hollis, Larry C.
Adapting to the lactating state requires metabolic adjustments in multiple tissues, especially in the dairy cow, which must meet glucose demands that can exceed 5 kg/day in the face of negligible gastrointestinal glucose absorption. These challenges are met through the process of homeorhesis, the alteration of metabolic setpoints to adapt to a shift in physiological state. To investigate the role of inflammation-associated pathways in these homeorhetic adaptations, we treated cows with the nonsteroidal anti-inflammatory drug sodium salicylate (SS) for the first 7 days of lactation. Administration of SS decreased liver TNF-? mRNA and marginally decreased plasma TNF-? concentration, but plasma eicosanoids and liver NF-?B activity were unaltered during treatment. Despite the mild impact on these inflammatory markers, SS clearly altered metabolic function. Plasma glucose concentration was decreased by SS, but this was not explained by a shift in hepatic gluconeogenic gene expression or by altered milk lactose secretion. Insulin concentrations decreased in SS-treated cows on day 7 compared with controls, which was consistent with the decline in plasma glucose concentration. The revised quantitative insulin sensitivity check index (RQUICKI) was then used to assess whether altered insulin sensitivity may have influenced glucose utilization rate with SS. The RQUICKI estimate of insulin sensitivity was significantly elevated by SS on day 7, coincident with the decline in plasma glucose concentration. Salicylate prevented postpartum insulin resistance, likely causing excessive glucose utilization in peripheral tissues and hypoglycemia. These results represent the first evidence that inflammation-associated pathways are involved in homeorhetic adaptations to lactation. PMID:23678026
Farney, Jaymelynn K; Mamedova, Laman K; Coetzee, Johann F; KuKanich, Butch; Sordillo, Lorraine M; Stoakes, Sara K; Minton, J Ernest; Hollis, Larry C; Bradford, Barry J
|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.
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
BioEd Online is an Ã¢ÂÂeducational resource for educators, students, and parentsÃ¢ÂÂ from the Baylor College of Medicine. This is an excellent place to find educational materials and current information in the field of biology. The Ã¢ÂÂHot TopicsÃ¢ÂÂ section of this site focus on current events and issues in biology that are Ã¢ÂÂreceiving national attention.Ã¢ÂÂ Mad Cow Disease has remained a challenge to scientists and regulatory commissions since its discovery in 1986. This Ã¢ÂÂHot TopicÃ¢ÂÂ 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.
Moreno, Nancy; Clayton, Sonia; Denk, James
Cow's milk is increasingly suggested to play a role in the development of chronic degenerative, non-communicable disorders whereas goat's milk is advocated as having several health benefits. Cow's milk is a rich and cheap source of protein and calcium, and a valuable food for bone health. Despite their high content in saturated fats, consumption of full-fat dairy products does not seem to cause significant changes in cardiovascular disease risk variables. Early introduction of cow's milk is a strong negative determinant of iron status. Unmodified cow's milk does not meet nutritional requirements of infants although it is acceptable to add small volumes of cow's milk to complementary foods. Cow's milk protein allergy has a prevalence ranging from 2 to 7%, and the age of recovery is usually around 2-3 years. The evidence linking cow's milk intake to a later risk of type 1 diabetes or chronic degenerative, non-communicable disorders (obesity, metabolic syndrome, type 2 diabetes, hypertension) is not convincing. Milk probably protects against colorectal cancer, diets high in calcium are a probable cause of prostate cancer, and there is limited evidence suggesting that high consumption of milk and dairy products increases the risk for prostate cancer. There is no evidence to support the use of a cow's milk-free diet as a primary treatment for individuals with autistic spectrum disorders. Unmodified goat's milk is not suitable for infants because of the high protein and minerals content and of a low folate content. Goat's milk has no clear nutritional advantage over cow's milk and is not less allergenic. The European Food Safety Authority recently stated that proteins from goat's milk can be suitable as a protein source for infant and follow-on formula, provided the final product complies with the compositional criteria laid down in Directive 2006/141/EC. PMID:24029787
Effect of Water Deprivation on Eating Patterns of Lactating Cows Fed Grass and Corn Pellets Ad Lib 1 1 Portions of the data were reported at the 8th International Symposium on Ruminant Physiology, Willingen, Germany, September 1994 (Langhans, W.; Rossi, R.; Scharrer, E. In: von Engelhardt, W.; Leonhard-Marek, S.; Breves, G.; Giesecke, D., eds. Ruminant physiology: Digestion, metabolism, growth and reproduction. Stuttgart: Enke; 1995:199216)
The present study investigated the effect of 48 h of water deprivation on eating behavior of 12 lactating cows fed grass and corn pellets ad lib. Water deprivation reduced grass and corn pellet intake significantly, with corn pellet intake decreasing earlier than grass intake. The reduction of feed intake was entirely due to a reduction of meal size for both
MARKUS SENN; SINA GROSS-LÜEM; ADRIAN KAUFMANN; WOLFGANG LANGHANS
...Waters 2 2009-07-01 2009-07-01 false COW operations: Meeting manual requirements. 157...VESSELS CARRYING OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Cow Operations Â§ 157.156 COW operations:...
...Waters 2 2010-07-01 2010-07-01 false COW operations: Meeting manual requirements. 157...VESSELS CARRYING OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Cow Operations Â§ 157.156 COW operations:...
Life history theory suggests that investment in reproduction can trade off against growth, longevity and both reproduction and performance later in life. One possible reason for this trade-off is that reproduction directly causes somatic damage. Oxidative stress, an overproduction of reactive oxygen species in relation to cellular defences, can correlate with reproductive investment and has been implicated as a pathway leading to senescence. This has led to the suggestion that this aspect of physiology could be an important mechanism underlying the trade-off between reproduction and lifespan. We manipulated female reproductive investment to test whether oxidative stress increases with reproduction in mice. Each female's pups were cross-fostered to produce litters of either two or eight, representing low and high levels of reproductive investment for wild mice. No differences were observed between reproductive groups at peak lactation for several markers of oxidative stress in the heart and gastrocnemius muscle. Surprisingly, oxidative damage to proteins was lower in the livers of females with a litter size of eight than in females with two pups or non-reproductive control females. While protein oxidation decreased, activity levels of the antioxidant enzyme superoxide dismutase increased in the liver, suggesting this may be one pathway used to protect against oxidative stress. Our results highlight the need for caution when interpreting correlative relationships and suggest that oxidative stress does not increase with enhanced reproductive effort during lactation. PMID:23619417
Garratt, Michael; Pichaud, Nicolas; King, Edith D Aloise; Brooks, Robert C
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
Cows prefer to spend more time lying down in free stalls with more bedding, but no research to date has addressed the effects of bedding quality. Bedding in stalls often becomes wet either from exposure to the elements or from feces and urine. The aim of this study was to test the effect of wet bedding on stall preference and use. Four groups of 6 nonlactating Holstein cows were housed in free stalls bedded daily with approximately 0.1 m of fresh sawdust. Following a 5-d adaptation period, each group of cows was tested sequentially with access to stalls with either dry or wet sawdust bedding (86.4 +/- 2.1 vs. 26.5 +/- 2.1% dry matter), each for 2 d. These no-choice phases were followed by a 2-d free-choice phase during which cows had simultaneous access to stalls containing either wet or dry bedding. Stall usage was assessed by using 24-h video recordings scanned at 10-min intervals, and responses were analyzed by using a mixed model, with group (n = 4) as the observational unit. The minimum and maximum environmental temperatures during the experiment were 3.4 +/- 2.2 and 6.8 +/- 2.5 degrees C, respectively. When cows had access only to stalls with wet bedding, they spent 8.8 +/- 0.8 h/d lying down, which increased to 13.8 +/- 0.8 h/d when stalls with dry bedding were provided. Cows spent more time standing with their front 2 hooves in the stall when provided with wet vs. dry bedding (92 +/- 10 vs. 32 +/- 10 min/d). During the free-choice phase, all cows spent more time lying down in the dry stalls, spending 12.5 +/- 0.3 h/d in the dry stalls vs. 0.9 +/- 0.3 h/ d in stalls with wet bedding. In conclusion, dairy cows show a clear preference for a dry lying surface, and they spend much more time standing outside the stall when only wet bedding is available. PMID:18024737
Fregonesi, J A; Veira, D M; von Keyserlingk, M A G; Weary, D M
Background An elevated plasma glucose concentration has been considered to be a potential risk factor in the pathogenesis of left-displaced abomasums (DA). Therefore the present study was performed to investigate if spontaneous disease (parturient paresis, metritis, ketosis etc) in dairy cows results in elevated concentrations of glucose and cortisol in blood as cortisol is the major regulator of glucose in ruminants. Methods Cortisol, insulin, ?-hydroxybutyric acid (BHBA), non esterified fatty acids (NEFA), and serum calcium were analyzed in blood serum and glucose, in whole blood, from 57 spontaneously diseased cows collected at different farms. The cows were grouped according to the disease; parturient paresis, recumbent for other reasons, mastitis, metritis, ketosis, inappetance and others. Results No elevated concentrations of cortisol or glucose were found in cows with metritis and mastitis but both cortisol and glucose were elevated in cows stressed by recumbency. Cows with ketonemia (BHBA > 1.5 mmol/l) did not have low concentration of glucose in blood but significantly low levels of cortisol. Some of these cows even had cortisol concentrations below the detection limit of the analysing method (< 14 nmol/l). Conclusions The study gives patho-physiological support to the treatment strategies of ketosis, recommending glucocorticoids, insulin etc. However further studies of this problem are needed to understand why cows with ketosis have low levels of cortisol and normal levels of glucose. To what extent elevated cortisol and glucose levels in hypocalcemic and recumbent cows are involved in the ethiology and /or the pathogenesis of DA also will need further research.
The working hypothesis was that postpartum anovulatory intervals (PPAI) of grazing dairy cows are shortened by inclusion of concentrates that increase the nonstructural carbohydrate content of the transition diet. Dietary treatments were arranged as a 2x2 factorial, with 68 multiparous cows assigned to isoenergetic diets (114 MJ of metabolizable energy/cow per day) of pasture and pasture silage (PreP) or pasture and pasture silage supplemented with 3 kg of dry matter/cow per day a corn- and barley-based concentrate for 36 d prepartum (PreC). After calving, cows within each prepartum diet group were managed on isoenergetic diets (179 MJ of metabolizable energy/cow per day) of either pasture and pasture silage (PostP) or pasture and pasture silage supplemented with 5 kg of dry matter/cow per day a corn- and barley-based concentrate (PostC) for at least 35 d and until reestablishment of ovulatory cycles. Relative to day of calving (d 0), blood samples were collected at least weekly from d -28 to 35 and milk samples were collected twice weekly for progesterone determination to diagnose ovulatory status. The main variable of interest was PPAI, defined as the interval between calving and the first detected increase in milk progesterone (>3 ng/mL), followed by a pattern of progesterone concentrations consistent with onset of an ovulatory cycle. Subsequent mating records, pregnancy testing, and recalving data were also examined. Prepartum diet did not affect reproduction. The PPAI was 8 d shorter and the 6-wk pregnancy rate was 17% greater in PostC cows compared with PostP cows. Measured indicators of metabolic state and energy balance were poorly related to PPAI. The results support the existence of nutritional signals associated with nonstructural carbohydrates in the postpartum diet, independent of energy balance; these signals benefit the physiological mechanisms underlying the timing of first ovulation and possibly subsequent breeding performance. PMID:20723702
Burke, C R; Kay, J K; Phyn, C V C; Meier, S; Lee, J M; Roche, J R
The present work compared metabolic and immune responses in genetically high-producing cows that produced a low amount of milk before expected involution and in cows with the same genetic potential that produced copious amounts of milk before their scheduled drying-off. Ten multiparous lactating Israeli Holstein cows producing approximately 10,500L in the current lactation, without bacterial infection and scheduled for drying-off approximately 60d before their expected parturition, were studied. Five of the cows that exhibited a sharp, spontaneous reduction in milk yield at the end of their lactation and produced less than ~14L/d were defined as cows approaching natural involution (ANI), and 5 cows that produced between 25 and 35L/d were defined as cows approaching forced involution (AFI). Three days before scheduled drying-off, milking was stopped and milk samples were collected from each quarter. After milking cessation, only modest swelling was observed in the udders of the ANI cows. In the ANI cows, lactose and fat concentrations decreased and the fat:lactose concentration ratio indicated that on d 1 and 2 fat concentrations decreased faster than lactose concentration, whereas on d 3, the rate of reduction was about the same for lactose and fat. In contrast, in AFI cows, fat concentrations increased on d 1 and the fat:lactose ratio indicated that changes in fat secretion were minor compared with those of lactose secretion. Rennet clotting time of milk after drying-off in the ANI cows increased, whereas curd firmness decreased rapidly, such that mammary secretions did not coagulate on d 3. In the AFI cows, such significant changes were observed only on d 3. The inflammatory response increased in both groups, but at each stage the increase was greater in ANI cows than in AFI cows. On d 1, the increase in leukocyte numbers in the ANI cows was made up of mononuclear cells (i.e., T lymphocytes and macrophages). In contrast, in the AFI cows, we observed a marked increase in leukocyte numbers, mainly in the form of polymorphonuclear cells. Our data indicate that the abrupt mammary involution induced in AFI cows provoked signs of distress, which were associated with neutrophilia in milk. In contrast, in the ANI cows, cessation of milking occurred without evidence of engorgement of the udder. Physiological differences in ANI and AFI cows are distinct and are reflected in the differences in the leukocyte populations in milk. PMID:23932133
Silanikove, Nissim; Merin, Uzi; Shapiro, Fira; Leitner, Gabriel
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.
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 log(10) · 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
Rapp, Delphine; Ross, Colleen M; Pleydell, Eve J; Muirhead, Richard W
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.
Ross, Colleen M.; Pleydell, Eve J.; Muirhead, Richard W.
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
Four macrominerals have the distinction of being involved in the 'downer cow' syndrome, which is, unfortunately, often associated with parturition in cows. Inadequate blood calcium (Ca), phosphorus (P), magnesium (Mg), or potassium (K) concentrations can cause a cow to lose the ability to rise to h...
IN Kirke's ``Physiology'' (p. 128, 7th edition) mention is made of a conception, due to Mr. Savory, concerning a probable function of the Sinuses of Valsalva, which appears to me to be based on a neglect of an important hydrostatical law. And as this error is not only widely spread, but is considered a point of some importance among students
W. Percy Ashe
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.
This research program has been concerned with evaluating the influence of various stressors, physiological and psychological, on man and subsequently determining the capacity of the individual to successfully adapt to these environmental influences. In th...
S. M. Horvath
After having unfolded the principal potentials of photosynthesis in Clusia in Chap. 8 we will now look at its performance at the plant community level. The simple single morphotype of Clusia gains diversity by the various life forms it produces (Sect. 2.3) and by its high physiological and biochemical plasticity\\u000a (Chap. 8). Clusia is extraordinarily successful in various tropical habitats
\\u000a Improvement in both temporal and spatial resolution of MDCT has brought the ability to explore both the heart and lung within\\u000a a single examination and opened the field of functional evaluation. However, interactions between heart and lung have long\\u000a been identified as important physiological phenomena in pathology (Pinsky 2005). For the radiologist, they are involved in difficulties of interpretation in
Francois Laurent; Michel Montaudon
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.
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
The physiological principles of Spa Treatment are explained on an adaptation model with three stages of adaptive modification: 1. autonomic recovery, 2. functional adaptation, 3. trophic and plastic adaptation. The stressors are the stimuli of the physical therapy which form adaptates during the spa treatment. These adaptates are directly dependent on the quantity and specificity of the stressors. Clinical symptomatology is elucidated practically with reference to two therapeutic principles and substantiated by results from spa research. The effects and long-term success of the treatment are scientifically demonstrated from the point of view of physiological adaptation. PMID:306516
We describe a moving virtual fence algorithm for herding cows. Each animal in the herd is given a smart collar consisting of a GPS, PDA, wireless networking and a sound amplifier. Using the GPS, the animal's location can be verified relative to the fence boundary. When approaching the perimeter, the animal is presented with a sound stimulus whose effect is
Zack J. Butler; Peter I. Corke; Ronald A. Peterson; Daniela Rust
Sociability is the relative preference of individual animals to seek out close contact with conspecifics. The aim of this study was to develop suitable tests that could be used to measure the sociability of individual cows on commercial farms. A standardised runway test was used as a gold standard test of social motivation and was repeated three times on 46
Jenny M. Gibbons; Alistair B. Lawrence; Marie J. Haskell
An earlier paper (1) has described the procedure in connection with the feeding trials. These were conducted during the winter of 1953-54, with six cows allotted to two sub-groups of three each, representing the Ayrshire, Holstein, and Jersey breeds. Each breed pair was matched as closely as possible with respect to stage of lactation. The supplement fed was aluminum potassium
J. G. Archibald
Recent measurements of remarkable dive performances in oceanic seabirds and marine mammals suggest the use of a range of physiological and behavioural adaptations for the parsimonious use of oxygen. Access to food at different depths may be directly related to the duration of the breath-hold, and several physiological strategies may be used to extend dive duration. But is also a
I. L. Boyd
Aviation physiology should be known at least in parts by the physicians advising air travellers. Due to reducing atmospheric pressure at altitude gas volume in body cavities expands (Boyle's law). This might not be a problem during ascend since air can disappear easily through natural ways. However, air must return to body cavities during descend and a person with a cold may suffer from painful barotitis. Hypoxia is mostly due to a reduced pO2 in high altitude (Daltons's Law). This may be prevented by an aircraft cabin or supplemented oxygen. Decompression sickness is very rare in aviation but divers should comply to a dive free interval before flying. PMID:10568247
Frank, P W
Three studies were conducted to investigate age related changes in thermoregulation observed in previous heat stress studies. Sweating threshold and capacity under thermal stress were studied in ten postmenopausal women and ten younger women. Age effects ...
B. L. Drinkwater S. M. Horvath
Rumen fill may be a strong intake constraint for dairy cows fed on pasture, even though pasture is highly digestible in the grasslands of temperate climates. This constraint may also depend on the cows' maturity. Moreover, indoor feeding of fresh herbage may not always be a good model for the study of intake regulation at grazing. To test these hypotheses, four mature (6.3 ± 0.72 year old) and four young (3.8 ± 0.20 year old) dairy cows were offered fresh perennial ryegrass indoors or at grazing. The impact of rumen fill on intake was evaluated by addition of rumen inert bulk (RIB; coconut fiber, 15 l) compared to a control. The experimental design was a double 4 × 4 Latin square with four 14-day periods and a 2 × 2 factorial arrangement of two feeding methods (indoor feeding v. grazing), combined with the addition, or not, of RIB (RIB v. control), repeated for four mature and four young cows. Digestibility of offered herbage was 0.81. The average ytterbium measured dry matter intake (Yb DMI) was 19.0 and 15.5 kg/day for mature and young cows respectively (P = 0.019). The effect of RIB on predicted Yb DMI interacted with feeding method and cow age (P = 0.043). The presence of RIB decreased Yb DMI by 4.4 kg/day in mature cows at grazing and by 3.4 kg/day in young cows indoors, whereas it did not affect the Yb DMI of mature cows indoors or grazing young cows. Both grazing and young age constituted a clear constraint on the feeding behavior of the cows. Grazing cows had fewer ingestion and rumination sequences, which were longer and less evenly distributed throughout the day and night. Young cows had lower intake rates that were less adaptable to the feeding method and the presence of RIB. Mature cows clearly decreased their daily intake rate at grazing compared to indoor feeding, and with RIB compared to control, whereas the intake rate of young cows did not vary. These results indicate that rumen fill can represent a constraint on intake in grazing cows, even when highly digestible perennial ryegrass is offered. The study also shows that the impact of RIB on intake is highly dependent upon other constraints applied to the chewing behavior, which in this experiment were methods of offering herbage and cow age. PMID:22443555
Boudon, A; Peyraud, J-L; Faverdin, P; Delagarde, R; Delaby, L; Chaves, A V
...Physical examination of cows. 1210.12...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...FEDERAL IMPORT MILK ACT Inspection...examination of cows. (a) Physical...of any and all cows in herds producing milk or cream...
...Physical examination of cows. 1210.12...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...FEDERAL IMPORT MILK ACT Inspection...examination of cows. (a) Physical...of any and all cows in herds producing milk or cream...
Forty pluriparous (M) and 20 primiparous (P) suckled Brahman cows were used to evaluate the effect of aspirin and parity on plasma 13,14-dihydro-15-keto-prostaglandin F2alpha (PGFM) and progesterone (P4) concentrations and some reproductive parameters. On Day 7 after calving (PP), the cows were allocated within parity into 2 groups: the aspirin group received concentrate containing aspirin at a rate of 100 mg/kg of body weight every 12 h until Day 13 PP; and the control received concentrate every 12 h for the same interval. Blood samples were collected after first and last aspirin feeding and daily from Day 1 PP to Day 6 PP and from Day 14 PP to Day 21 PP, twice daily from Day 7 PP to Day 13 PP, and weekly until first non-return to estrus. Plasma salicylate concentrations in the aspirin group cows were affected by parity (P < 0.01) and time after feeding (P < 0.0001). P cows showed higher plasma salicylate concentrations with a later peak and slower decrease than M cows. Aspirin-treated P cows had longer PP intervals than either control P, control M, or aspirin-treated M cows. Cows receiving aspirin had a lower pregnancy rate, an increased incidence of abnormal estrous cycles, and a decline in the presence of corpora lutea after estrus. Cows that formed a corpora lutea and had received aspirin had higher P4 release between Day 6 and 14 after estrus. Aspirin-treated cows that did not form corpora lutea had lower P4 release between Days 9 and 14 after estrus. A treatment by parity interaction affected mean PGFM proportions (P < 0.01) during the treatment period. Aspirin-fed P cows increased PGFM release as measured by mean proportion of Day 6 PP values. Aspirin-fed M cows showed a decrease in mean PGFM proportions. Aspirin feeding during the early PP showed different effects on some reproductive parameters in P and M Brahman cows, indicating differences in PP physiology between parities. PMID:10560615
Stahringer, R C; Neuendorff, D A; Randel, R D
Objectives were to develop a system to administer exercise training to dairy cows, to measure potential physiological indicators of fitness, and to assess physical fitness. Nonlactating, nonpregnant multiparous Holstein cows (n = 19) were in one of three exercise training treatments: no exercise; 1-h exercise; or 2-h exercise by walking 3 km/h every other day for 60 d in a mechanical walker. Treadmill tests on d 15, 30, 45, and 60 consisted of walking (5 km/h) with 1.6% increases in slope at 3-min intervals until heart rates reached 180 beats per minute (experimentally specified maximum) or until cows refused to walk. Fitness indices analyzed in tests as single datum points at maximal heart rates were length of time of test, heart rate, and plasma L-lactate concentration at end of the test, and change in heart rate and lactate concentration during the test. Exercised (1 or 2 h) cows had longer times to end of tests than nonexercised cows. Maximal and change in heart rates or plasma lactate during tests did not indicate improved physical fitness. However, when all data were evaluated as repeated measures of day and minute of tests, reductions of heart rates and plasma lactate concentrations were greatest on d 60 between exercised and nonexercised cows indicating improved fitness. Acid-base measurements were not found useful in this study. Changes of heart rates and plasma lactate concentrations over time (repeated measures) of treadmill tests quantified the physical fitness of dairy cows and can be used to compare potential responses to different exercise training treatments in this system. PMID:14507020
Davidson, J A; Beede, D K
The aim of this study was to investigate the variations of some physiological parameters in dairy cows during subacute ruminal\\u000a acidosis (SARA), a common important disorder of dairy cows that occurs in early lactation. pH changes in ruminal fluid collected\\u000a by rumenocentesis were measured at ten farms stationed in different zones in the north of Italy. Additionally, the following\\u000a parameters
M. Morgante; M. Gianesella; S. Casella; L. Ravarotto; C. Stelletta; E. Giudice
The aim of this study was to obtain information on the frequency of cervical dystocia and involution disorders of the canalis cervicalis after difficult dystocia and to characterise factors possibly influencing these pathological conditions. Therefore 317 difficult births in the cow (extraction: 123; foetotomy: 82; caesarean section: 112) and the involution of the cervical canal were documented during the first ten days post partum. In total a cervical dystocia could be diagnosed 53 times (16.7% related to the total number of births). This kind of birth disorder is regularly followed by a caesarean section (p < 0.001). Animals who show a narrowness in the cervix were older than the cows without cervical dystocia (p < 0.05). The same correlation could be detected for the number of births. Animals with delivery problems associated with the cervix had already given birth to more calves than cows who were not affected by cervical disorders (p < 0.01). 58 cows developed a disorder of the cervical involution (18.3% related to the total number of deliveries). This puerperal disorder can be frequently observed after foetotomy (p < 0.001). A correlation between the incidence of disorders of cervical involution and the age or the parity of the animals could not be detected. In the same way, cows with a diagnosis of a cervical dystocia did not develop more frequently disorders of cervical involution than animals who showed a physiological dilation of the cervical canal intra partum. PMID:14746054
Wehrend, A; Bostedt, H
To aid in unraveling diverse genetic and biological unknowns, a proteomic approach was used to analyze the whey proteome in cow, yak, buffalo, goat, and camel milk based on the isobaric tag for relative and absolute quantification (iTRAQ) techniques. This analysis is the first to produce proteomic data for the milk from the above-mentioned animal species: 211 proteins have been identified and 113 proteins have been categorized according to molecular function, cellular components, and biological processes based on gene ontology annotation. The results of principal component analysis showed significant differences in proteomic patterns among goat, camel, cow, buffalo, and yak milk. Furthermore, 177 differentially expressed proteins were submitted to advanced hierarchical clustering. The resulting clustering pattern included three major sample clusters: (1) cow, buffalo, and yak milk; (2) goat, cow, buffalo, and yak milk; and (3) camel milk. Certain proteins were chosen as characterization traits for a given species: whey acidic protein and quinone oxidoreductase for camel milk, biglycan for goat milk, uncharacterized protein (Accession Number: F1MK50 ) for yak milk, clusterin for buffalo milk, and primary amine oxidase for cow milk. These results help reveal the quantitative milk whey proteome pattern for analyzed species. This provides information for evaluating adulteration of specific specie milk and may provide potential directions for application of specific milk protein production based on physiological differences among animal species. PMID:23464874
Yang, Yongxin; Bu, Dengpan; Zhao, Xiaowei; Sun, Peng; Wang, Jiaqi; Zhou, Lingyun
On an experimental farm, five camels and five cows were fed with a similar basal diet over a 6-month period. They received an oral trace element supplement for 3 months (days 22-112). This supplement contained zinc and copper sulphate, and corresponded to twice the daily requirement generally recommended for cows. Plasma zinc and copper concentrations were significantly lower in camels (44 micrograms/100 mL for copper and 38 micrograms/100 mL for zinc) than in cows (106 and 83 micrograms/100 mL, respectively). The supplementation had no effect on the plasma zinc concentration in the camels in spite of the low observed values. The mean erythrocyte SOD activity was also significantly higher in the cows (2,404 +/- 211 IU/100 gHb) than in the camels (1,720 +/- 312 IU/100 gHb). In both species, no correlation was found between copper plasma concentration and erythrocyte SOD activity. In cows, a positive relationship was observed between plasma zinc concentration and SOD activity (r = 0.396). In contrast, a negative relationship was found in camels (r = -0.369). These results are discussed in relation to the physiological peculiarities of the camel. PMID:9851012
Bengoumi, M; Essamadi, K; Charcornac, J P; Tressol, J C; Faye, B
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
Background: Cows milk allergy is the most common cause of clinically relevant adverse reactions to food in infants and children. Partially and extensively hydrolyzed formulae are used for the therapy and prevention of cows milk allergy. However, the immunogenic potency of hydrolyzed cows milk formulae to induce and\\/or enhance the allergic phenotype in vivo is still under debate. The aim
Bodo Niggemann; Hartmut Nies; Harald Renz; Udo Herz; Ulrich Wahn
Background: Cows milk is one of the most common causes of food allergy in the first years of life. We recently defined IgE and IgG binding epitopes for ?s1-casein, a major cows milk allergen, and found an association between recognition of certain epitopes and clinical symptoms of cows milk allergy (CMA). Since ?-lactalbumin (ALA) and ?-lactoglobulin (BLG) are suspected to
Kirsi-Marjut Järvinen; Pantipa Chatchatee; Ludmilla Bardina; Kirsten Beyer; Hugh A. Sampson
The purpose of this study was to examine the stability and host specificity of a cow's ruminal bacterial community following massive challenge with ruminal microflora from another cow. In each of 2 experiments, 1 pair of cows was selected on the basis of differences in ruminal bacterial community composition (BCC), determined by automated ribosomal intergenic spacer analysis (ARISA), a culture-independent "community fingerprinting" technique. Each pair of cows was then subjected to a 1-time exchange of >95% of ruminal contents without changing the composition of a corn silage/alfalfa haylage-based TMR. In experiment 1, the 2 cows differed (P<0.01) in prefeed ruminal pH (mean = 6.88 vs. 6.14) and prefeed total VFA concentration (mean = 57 vs. 77 mM), averaged over 3 d. Following exchange of ruminal contents, ruminal pH and total VFA concentration in both cows returned to their preexchange values within 24h. Ruminal BCC also returned to near its original profile, but this change required 14 d for 1 cow and 61 d for the other cow. In experiment 2, the 2 other cows differed in prefeed ruminal pH (mean = 6.69 vs. 6.20) and total VFA concentration (mean = 101 vs. 136 mM). Following exchange of ruminal contents, the first cow returned to its preexchange pH and VFA values within 24h; the second cow's rumen rapidly stabilized to a higher prefeed pH (mean = 6.47) and lower prefeed VFA concentration (mean = 120 mM) that was retained over the 62-d test period. Both cows reached somewhat different BCC than before the exchange. However, the BCC of both cows remained distinct and were ultimately more similar to that of the preexchange BCC than of the donor animal BCC. The data indicate that the host animal can quickly reestablish its characteristic ruminal pH and VFA concentration despite dramatic perturbation of its ruminal microbial community. The data also suggest that ruminal BCC displays substantial host specificity that can reestablish itself with varying success when challenged with a microbial community optimally adapted to ruminal conditions of a different host animal. PMID:21094763
Weimer, P J; Stevenson, D M; Mantovani, H C; Man, S L C
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.
Physiological adaptation to low temperatures of strains of Rhizobium leguminosarum bv. viciae associated with Lathyrus spp. 1 1 Contribution No. 658 of Agriculture and Agri-Food Canada Research Centre at Sainte-Foy
Strains of Rhizobium leguminosarum bv. viciae, isolated from the legume species Lathyrus japonicus and Lathyrus pratensis in northern Quebec (Canada), showed different capacities for growing at low temperature. In the present study, we investigated some mechanisms related to cold adaptation. Two cold-adapted strains (psychrotrophs) were compared to a poorly adapted strain and to a cold-sensitive strain (reference strain) for freezing
Pascal Drouin; Danielle Prévost; Hani Antoun
Mycobacterium tuberculosis is a prototrophic, metabolically flexible bacterium that has achieved a spread in the human population that is unmatched by any other bacterial pathogen. The success of M. tuberculosis as a pathogen can be attributed to its extraordinary stealth and capacity to adapt to environmental changes throughout the course of infection. These changes include: nutrient deprivation, hypoxia, various exogenous stress conditions and, in the case of the pathogenic species, the intraphagosomal environment. Knowledge of the physiology of M. tuberculosis during this process has been limited by the slow growth of the bacterium in the laboratory and other technical problems such as cell aggregation. Advances in genomics and molecular methods to analyse the M. tuberculosis genome have revealed that adaptive changes are mediated by complex regulatory networks and signals, resulting in temporal gene expression coupled to metabolic and energetic changes. An important goal for bacterial physiologists will be to elucidate the physiology of M. tuberculosis during the transition between the diverse conditions encountered by M. tuberculosis. This review covers the growth of the mycobacterial cell and how environmental stimuli are sensed by this bacterium. Adaptation to different environments is described from the viewpoint of nutrient acquisition, energy generation and regulation. To gain quantitative understanding of mycobacterial physiology will require a systems biology approach and recent efforts in this area are discussed. It is now 100 years since the first mycobacterium was isolated by Hansen (1874). Somewhat ironically, this was the leprosy bacillus, Mycobacterium leprae, which even today is still resisting all attempts to cultivate it in the laboratory. The tubercle bacillus, M. tuberculosis was not discovered until eight years later (Koch, 1882) and this has remained an object of intensive investigation ever since. The widespread interest in the mycobacteria of course stems from the diseases they cause and, lest it be imagined that tuberculosis is a disease which has now been largely conquered and that leprosy is of relatively rare occurrence, current estimates for the number of case of tuberculosis and leprosy in the world today are 20,000,000 and 11,000,000, respectively (Bechelli and Dominguez, 1972). The annual estimated mortality rate is equally dramatic, namely 3,000,000 (World Health Organization, 1974). Also causing unease is the continuing isolation from tubercular patients of strains already resistant to one or more chemotherapeutic agent. C. Ratledge (1976).
Cook, Gregory M.; Berney, Michael; Gebhard, Susanne; Heinemann, Matthias; Cox, Robert A.; Danilchanka, Olga; Niederweis, Michael
Dietary constituents can affect cow acid-base physiology and uterine pH. Dietary cation-anion difference (DCAD) has been shown to affect cow acid-base physiology, but the effect on uterine pH has not been demonstrated. The objective of this work was to determine if DCAD [(Na + K + 0.15Ca + 0.15Mg) - (Cl + 0.60S + 0.50P)] could affect cow DMI, acid-base physiology, and uterine pH, and second, to determine if dietary supplements could alleviate any negative effects of DCAD on these variables. In Exp. 1, 21 cows were utilized to determine the effect of a negative DCAD (-0.9 mEq/100 g of DM; low-DCAD) or positive DCAD (+25.0 mEq/100 g of DM; high-DCAD) diet on cow BW, DMI, and pH of blood, urine, and uterine flush fluid. In Exp. 2, 21 cows were randomly allotted to 1 of 3 treatments: control (-3.1 mEq/100 g of DM), molasses (+2.9 mEq/100 g of DM), or molasses+buffer (+25.8 mEq/100 g of DM) to determine if supplemental liquid molasses or liquid molasses with a buffer could alleviate the effects of a negative DCAD, forage-based diet. Cows were individually fed their respective diets for 42 d in both experiments. Cow BW, blood, urine, and uterine flush were collected on d 0, 21, and 42 during both experiments. Cow ADG was not different (P = 0.71) in Exp. 1 or Exp. 2 (P = 0.47). Hay DMI did not differ (P < 0.70) between high-DCAD and low-DCAD cows before d 28, but was greater (P < 0.001) for high-DCAD cows after d 28 in Exp. 1. In Exp. 2, mean hay DMI did not differ (P = 0.39) among treatments. In Exp. 1, a treatment x day interaction (P < 0.05) was apparent for blood, pH, base excess, bicarbonate, pCO(2), and urine pH. Blood gas and pH measures peaked on d 21 for high-DCAD and declined from d 0 to 42 in low-DCAD cows. High-DCAD cows had greater (P = 0.08) uterine flush pH compared with low-DCAD cows. In contrast, during Exp. 2 there were no differences (P > 0.14) among treatments for blood, pH, base excess, pCO(2), or uterine flush pH. Urine pH exhibited a treatment x day interaction (P < 0.0001). On d 21 molasses supplemented cow urine pH was greater (P < 0.0001) than control cows, whereas on d 42 molasses+buffer had greater (P = 0.01) urine pH compared with control and molasses cows. Dietary cation-anion difference and the use of molasses-based supplements had minimal effect on forage-fed beef cow DMI. However, DCAD has the capacity to alter forage-fed beef cow acid-base physiology and potentially affect uterine physiology. PMID:19783689
Hersom, M J; Hansen, G R; Arthington, J D
Appraisal theorists propose physiological activity in emotion to be systematically organized around appraisal of the adaptational significance of the environment in ways that promote two functions commonly ascribed to emotion: communication and preparation for coping. However, relations between appraisal and physiological activity remain largely untested. This article reviews existing evidence to generate specific hypotheses linking appraisal to physiological activity and
Craig A. Smith
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
SUMMARY 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 Chulalongkorn 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
Jarungchit Ngamphaiboon; Pantipa Chatchatee; Thaneya Thongkaew
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 g...
Two postparturient beef cows in a herd of 30 developed acute enteritis, with pyrexia and bloody diarrhea containing intestinal casts. Salmonella typhimurium phage type 66 was isolated from feces of both animals; both recovered after treatment with tetracycline. A third cow had died without treatment after showing similar signs.
Pender, Andrew B.
A longitudinal study was conducted to examine the relationship between lameness and delayed ovarian cy- clicity during the first 60 d postpartum and days to first luteal activity during the first 300 d postpartum in Holstein cows. Two hundred thirty-eight cows from a 600-cow dairy that calved during a 12-mo period were used. Cows were classified into 1 of 6
E. J. Garbarino; J. A. Hernandez; J. K. Shearer; C. A. Risco; W. W. Thatcher
...examination of cows. 1210.12...OF HEALTH AND HUMAN SERVICES (CONTINUED...FEDERAL IMPORT MILK ACT Inspection...examination of cows. (a) Physical...in which such milk or cream is produced...whether such cow or cows are in a healthy...
...2009-07-01 2009-07-01 false COW tank washing machines. 157.124 Section...CARRYING OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Design, Equipment, and Installation Â§ 157.124 COW tank washing machines. (a) COW...
...2010-07-01 2010-07-01 false COW tank washing machines. 157.124 Section...CARRYING OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Design, Equipment, and Installation Â§ 157.124 COW tank washing machines. (a) COW...
The most common problem that cow calf producers face in the U.S. is low rebreeding performance among two- and three-year old cows. In Brazil, however, most cows are not bred until at least 2 years of age. However, the underlying reason that young cows in both countries have difficulty re-breeding ...
The content of human physiology as an independent part of current physiology is discussed. Substantiated is the point that subjects of human physiology are not only special sections of physiology where functions are inherent only in human (physiology of intellectual activity, speech, labor, sport), but also in peculiarities of functions, specificity of regulation of each of physiological systems. By the example of physiology of kidney and water-salt balance there are shown borders of norm, peculiarities of regulation in human, new chapters of renal physiology which have appeared in connection with achievements of molecular physiology. PMID:21061667
Natochin, Iu V
This report documents the significant upgrades and improvements made to the correlator optical wavefront sensor (COWS) optical bench during this phase of the program. Software for the experiment was reviewed and documented. Flowcharts showing the program flow are included as well as documentation for programs which were written to calculate and display Zernike polynomials. The system was calibrated and aligned and a series of experiments to determine the optimum settings for the input and output MOSLM polarizers were conducted. In addition, design of a simple aberration generation is included.
Heat stress has an enormous economic impact on the global dairy industry, but the mechanisms by which hyperthermia negatively affect systemic physiology and milk synthesis are not clear. Study objectives were to evaluate production parameters and metabolic variables in lactating dairy cows during short-term heat stress or pair-fed conditions coupled with bST administration. Twenty-two multiparous Holstein cows were subjected to 3 experimental periods: 1) thermoneutral conditions with ad libitum intake for 7 d (P1); 2) heat stress (HS) with ad libitum intake (n=10) or pair-fed (PF) in thermoneutral conditions (n=12) for 7 d (P2), and 3) 7 d of HS or PF in conditions as described in P2 with recombinant bovine somatotropin administered on d 1 (P3). All cows received an intravenous glucose tolerance test (GTT) on d 5 of each period. Heat stress conditions were cyclical and temperatures ranged from 29.4 to 38.9 degrees C. Rectal temperatures and respiration rates increased during heat stress (38.6-40.4 degrees C and 44-89 breaths/min, respectively). Heat stress reduced dry matter intake by 30% and by design PF cows had similar intake reductions (28%). During heat stress and pair-feeding, milk yield decreased by 27.6% (9.6kg) and 13.9% (4.8kg), respectively, indicating that reduced feed intake accounted for only 50% of the decreased milk production. Milk yield increased with recombinant bovine somatotropin in both HS (9.7%) and PF (16.1%) cows. Cows in both groups were in positive energy balance (3.95 Mcal/d) during P1 but entered negative energy balance during P2 and P3 (-5.65 Mcal/d). Heat stress and pair-feeding treatments decreased (9.3%) basal glucose concentrations. Heat stress conditions had no effect on basal NEFA levels during P2; however, PF cows (despite a similar calculated energy balance) had a 2-fold increase in basal NEFA concentrations. Both groups had increased plasma urea nitrogen levels during P2 and P3 compared with P1. Basal insulin levels increased (37%) during P2 and P3 in HS cows but did not differ between periods in PF cows. During P2 and compared with P1, PF cows had a decreased rate of glucose disposal, whereas HS cows had a similar disposal rate following the GTT. During P2 and compared with P1, PF cows had a reduced insulin response whereas HS cows had a similar insulin response to the GTT. In summary, reduced nutrient intake accounted for only 50% of heat stress-induced decreases in milk yield, and feed intake-independent shifts in postabsorptive glucose and lipid homeostasis may contribute to the additional reduction in milk yield. PMID:20105536
Wheelock, J B; Rhoads, R P; Vanbaale, M J; Sanders, S R; Baumgard, L H
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.
Shaw, Darcy; Gohil, Kartik; Basson, Marc D
Quantitative immunoelectrophoretic methods were used for the analysis of the allergens in cow hair and dander and for comparison with related preparations. The immunoelectrophoretic precipitation pattern of an extract from cow hair and dander showed 17 precipitates. Crossed radioimmunoelectrophoresis showed four of these to be major allergens of the extract, and these allergens are common major allergens in four investigated cow breeds. The allergens are associated predominantly with hair and dander, but they were also demonstrated in cow saliva, urine, whey, amniotic fluid and beef, as well as in cow-hide products. Allergens displaying partial immunological identity with the major allergens of cow hair and dander were found in extracts from goat and sheep pelts, in products made of these materials such as carpet and knitting wool, and in carpets made of animal hair. PMID:7337202
The objective of this study was to evaluate the effects of dietary forage sources on milk performance, rumen microbial protein synthesis, and N utilization in early lactation dairy cows. Twelve primiparous Chinese Holstein dairy cows (45 ± 6.0 DIM) were used in a 3 × 3 Latin square design. Diets were isonitrogenous and isocaloric, with a forage-to-concentrate ratio of 45:55 [dry matter (DM) basis] and contained similar concentrate mixtures. Different forage sources were then added (on a DM basis): 21% corn silage, 19% corn stover, and 5% alfalfa hay (CS); 19% corn silage, 21% Chinese wild rye hay and 5% alfalfa hay (CWR); or 19% corn silage, 9% Chinese wild rye hay, and 17% alfalfa hay (AH). Each period lasted for 21 d, with the first 14 d for an adaptation period. Dry matter intake was not affected by the source of dietary forage. Milk yield was higher for cows fed AH than those fed CS, with an intermediate value for CWR. Milk protein content was higher in the cows fed AH compared with CWR (3.02 vs. 2.92%), with CS (2.95%) at an intermediate position. The contents of milk fat and lactose were not different among the treatments. However, milk efficiency (milk yield/DM intake) was higher for cows fed AH than those fed CS, with those fed CWR intermediate. Cows fed AH had higher microbial protein yield and metabolizable protein than those fed CS or CWR. The concentrations of urea N in the urine, blood, and milk were decreased for cows fed AH, indicating an increased N conversion. The results indicated that corn stover could replace Chinese wild rye grass in the diets for lactating cows and that a high proportion of alfalfa hay in the diet is beneficial for milk protein production by increasing microbial protein yield. This can be attributed to the improving the supply of rumen-available energy. PMID:23295118
Zhu, W; Fu, Y; Wang, B; Wang, C; Ye, J A; Wu, Y M; Liu, J-X
This study investigated the effects of the administration of long chain omega-3 fatty acids (?-3 FA) and acetylsalicylic acid (ASA) on inflammation, performance, and fertility in periparturient dairy cows. Five weeks before calving, 26 multiparous dairy cows were randomly assigned to 1 of 3 treatments: ?-3 FA (n = 9; OME), ?-3 FA and ASA (n = 9; OMAS), or palm oil (n = 8; CTR). During the last 3 wk of pregnancy, OME and OMAS groups received daily 12.0 g of fish-derived ?-3 FA, whereas CTR cows received only SFA. In addition, OMAS cows received daily 6.0 mg ASA/kg BW starting at 7 d before calving. Only a few cows had health problems after calving, but those in OMAS were most affected (n = 3 vs. 1 in CTR). Inflammatory status around calving did not improve in OME cows, as confirmed by the patterns of concentration of acute-phase proteins (APP), which were similar to CTR. Compared with CTR and OME, the increase of the positive APP and the decrease of the negative APP (e.g., albumin; P < 0.01) observed in OMAS cows suggested a severe inflammatory status after calving. Compared with OMAS, postcalving energy metabolism was better in OME cows as shown by a lower degree of lipomobilization (smaller BCS drop, greater glucose) and milder ketogenesis (less ?-hydroxybutyrate; P < 0.01). Cows in CTR had optimal fertility indices, whereas OMAS was the worst group. The severe inflammation and the more negative energy balance likely contributed to the poor fertility parameters in those cows. It is known that ASA exerts an inhibitory effect on cyclooxygenases, causing a possible decrease in the synthesis of PGF2?. A decreased concentration of PGF2? is connected with alterations in the physiologic processes related to labor and to uterine motility. Cows in OMAS had a longer pregnancy (P < 0.10 vs.OME) and a greater frequency of retained placenta, which may be attributed to decreased synthesis of PGF2?. The administration of ?-3 FA alone did not delay calving or the expulsion of fetal membranes. In conclusion, long-chain ?-3 FA improved the physiological status of cows, partly through better energy balance. The administration of ASA before calving (even at a low dose) in combination with ?-3 FA did not exert any synergistic positive effect on inflammation and performance. PMID:23519730
Grossi, P; Bertoni, G; Cappelli, F Piccioli; Trevisi, E
There is a large amount of excitement and uncertainty about the management and nutrition of the transition cow. A good rule of thumb is that the more ways that are proposed to do something, the less certain it is which are correct. The wide range of opinions currently held on this subject probably means that our current knowledge about why fresh cows fail and how they should be treated and managed is inadequate. There is only one treatment for milk fever, and there are only two proper positions for a calf at calving. Yet fresh cow programs are proposed that range from intensive screening and treatment, including daily temperatures and drenching every fresh cow with a large amount of fluids, to nothing. PMID:15471627
Guterbock, Walter M
Bone-eating worms of the genus Osedax colonized and grew on cow bones deployed at depths ranging from 385 to 2893m in Monterey Bay, California. Colonization occurred as rapidly as two months following deployment of the cow bones, similar to the time it takes to colonize exposed whalebones. Some Osedax females found on the cow bones were producing eggs and some hosted dwarf males in their tubes. Morphological and molecular examinations of these worms confirmed the presence of six Osedax species, out of the eight species presently known from Monterey Bay. The ability of Osedax species to colonize, grow and reproduce on cow bones challenges previous notions that these worms are 'whale-fall specialists.' PMID:18077256
Jones, William J; Johnson, Shannon B; Rouse, Greg W; Vrijenhoek, Robert C
Two experiments in vivo and one experiment in vitro were conduced to examine the mechanisms involved, which lead to mammary secretion of oestrogens and its importance for milk production and udder health in cows. In experiment 1 in six cows of the White-Black breed on day 268 of pregnancy catheters were inserted into uterine vein of pregnant horn, the abdominal aorta and the caudal superficial epigastric (milk) vein. Blood samples for estimation of oestrone, oestrone sulphate, oestradiol-17alpha and -17beta by RIA were obtained daily from day 7 pre-partum until day 1 post-partum. Only the concentration of oestradiol-17beta was statistically higher (P< or =0.01) in mammary venous plasma than in aortal and uterine plasma. In experiment 2 forty late-pregnant cows were divided into two groups according to their milk production in the previous lactation: group 1 (n=20) high-yielding cows (>6500kg milk per lactation), and group 2 (n=20) low-yielding cows (<3700kg milk per lactation). Blood samples for measurement of oestradiol-17beta by RIA were collected from milk and tail veins every fourth day during a period from day 20 prior to parturition to day 4 post-partum. The concentration of oestradiol-17beta was significantly higher (P< or =0.01) in the milk vein than in the peripheral plasma from day 12 pre-partum to parturition. In high-yielding cows the level of oestradiol-17beta in mammary venous blood was significantly higher (P< or =0.01) than in low-yielding cows. In six cows with pathological udder oedema ante-partum the concentration of oestradiol-17beta in milk vein was significantly higher (P< or =0.05) than in control cows. There were no statistically significant differences in the levels of oestradiol-17beta in cows with clinical mastitis (n=10) during 2 weeks after parturition and without it (P> or =0.05). In an in vitro experiment, homogenates of mammary tissue collected on day 7 pre-partum from two cows were incubated with 3H-androstendione. After incubation the samples were extracted and 3H-oestradiol-17beta was separated by HPLC. 3H-oestradiol-17beta was formed in a total yield of 37%. These results indicate that oestrone, oestrone sulphate and oestradiol-17alpha are not secreted by bovine mammary gland. Furthermore, the secretion of oestradiol-17beta starts about day 12 pre-partum and is associated with milk yield and udder oedema. Preliminary in vitro study suggests the synthesis of oestradiol-17beta by mammary tissue. PMID:12142232
Janowski, T; Zdu?czyk, S; Malecki-Tepicht, J; Bara?ski, W; Ra?, A
Hypoallergenic cows milk (HA) formulas play an important role in the prevention of cows milk allergy in high risk children as well as in treatment strategies. This thesis describes the development of a murine model for cows milk allergy to analyze the residual allergenicity and sensitizing capacities of cows milk protein hydrolysates, as present in HA infant formulas. Safety testing
E. C. A. M. Lobato-van Esch
Adaptive human computer interaction is necessary for successfully closing the affective loop within intelligent interactive systems. This paper investigates the impact of adaptivity on the physiological state and the expressed emotional preferences of users. A physical interactive game is used as a test-bed system and its real-time adaptation mechanism is evaluated using a survey experiment. Results reveal that entertainment preferences
Georgios N. Yannakakis
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.
Some dairy producers resist using bovine somatotropin (bST) beginning at 9 wk postpartum because of the concern that fertility is compromised. We conducted a trial with a total of 205 Holstein cows, 100 multiparous and 105 primiparous, to evaluate reproductive performance in two high producing herds in Arizona and southern California. Rolling herd averages for both herds for milk production exceeded 10,700 kg/yr. Data were collected for cows calving December 1996 through August 1997. The voluntary waiting period was 60 d postcalving, with cows randomly assigned to receive bST or no treatment (controls). In the 180-d interval after calving, 65.4% (68/104) of the control cows were diagnosed pregnant. With bST-treated cows, 48.5% (49/101) were pregnant in that same interval. A chi-square value from a linear model indicated that pregnancy outcome differed significantly between treatment groups. With a similar method of analysis, first-service conception rate was not significantly different between treatment groups. An extended voluntary wait and breeding interval is recommended for cows receiving bST, similar to suggestions from other published reports. PMID:10908052
Luna-Dominguez, J E; Enns, R M; Armstrong, D V; Ax, R L
Transition from the dry period to lactation is a high risk period for the modern dairy cow. The biggest challenge at that time is mastitis. Environmental bacteria are the most problematic pathogens around parturition. Coliforms are able to cause severe infections in multiparous cows, and heifers are likely to be infected with coagulase-negative staphylococci. During the periparturient period, hormonal and other factors make the dairy cows more or less immunocompromised. A successful mastitis control programme is focused on the management of dry and calving cows and heifers. Clean and comfortable environment, proper feeding and adequate supplementation of the diet with vitamins and trace elements are essential for maintaining good udder health. Strategies which would enhance closure of the teat canal in the beginning of the dry period and would protect teat end from bacteria until the keratin plug has formed decrease the risk for mastitis after calving. Dry cow therapy has been used with considerable success. Yet, a selective approach could be recommended rather than blanket therapy. Non-antibiotic approaches can be useful tools to prevent new infections during the dry period, in herds where the risk for environmental mastitis is high. Vaccination has been suggested as a means to support the immune defence of the dairy cow around parturition. In some countries, implementation of Escherichia coli core antigen vaccine has reduced the incidence of severe coliform mastitis after calving. PMID:18638132
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
The aim of the present study was to evaluate the effects of a single treatment with FSH on diameter of the largest follicle and on conception rates of suckled Bos indicus beef cows submitted to timed artificial insemination (TAI). Four hundred fifty-six suckled anestrous Nelore beef cows at 30-60 days postpartum were assigned to treatments. At the first day of the estrous synchronization protocol (Day 0), all cows received a progesterone-releasing intravaginal device plus 2mg of estradiol benzoate. On Day 8, cows were assigned to blocks according to the diameter of the largest follicle and then allocated to one of three treatment groups (Control, FSH, or eCG) within each block. Simultaneously to progesterone device withdrawal on Day 8, cows in the eCG treatment group (n=150) received 300 IU of eCG and cows in FSH treatment group (n=153) received 10mg of FSH, and Control cows (n=153) did not receive any additional treatment. Additional treatments with 150 ?g of cloprostenol and 1mg of estradiol cypionate (EC) were also administered concurrently to progesterone device removal in all cows on Day 8. Two days later (D10), TAI and ovarian ultrasonic examinations to evaluate follicle size were performed in all cows. On Day 12, a subset of cows (n=389) were submitted a second ultrasonic exam to confirm ovulation. Final follicular growth (mm/day) was less (P=0.006) in both Control (0.95±0.11) and in FSH-treated cows (0.90±0.10) than in eCG-treated cows (1.40±0.13). Interestingly, there was a treatment-by-BCS interaction in ovulation results (P=0.03), in which, eCG treatment increased percentage of cows having ovulations with a lesser BCS. Similarly, there was a treatment-by-BCS interaction for conception (P=0.04), where the eCG treatment increased fertility in cows with a lesser BCS. In conclusion, FSH failed to stimulate final follicular growth, ovulation, and conception rate in sucked-anestrous beef cows submitted to TAI as effectively as eCG. However, physiological effects of eCG seem to be more evident in cows with a lesser BCS. PMID:21376482
Sales, J N S; Crepaldi, G A; Girotto, R W; Souza, A H; Baruselli, P S
The prophylactic use of intramammary antimicrobial drugs at the end of lactation in dairy cows, known as dry cow therapy (DCT), is widely practiced in US dairy herds. This extremely common use of high-dose, slow-release antimicrobials may influence the ecology of bacterial flora on dairy farms. We investigated the association between the antimicrobial used for intramammary DCT and the relative
Dixie F. Mollenkopf; Candace Glendening; Thomas E. Wittum; Julie A. Funk; Lesley A. Tragesser; Paul S. Morley
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
Studies were carried out in 2 groups of calves from cows fed a hay-free keto- and acidosis-producing diet (group I) and a diet containing an excess of protein and starch (group II). The laboratory studies were conducted: in cows ante partum, and in calves prior to and 3 hours after drinking colostrum, and on the 1st, 3rd, 14th and 30th day of life. The determined parameters were: hematologic, acid alkaline balance and metabolism of protein, saccharide and fat. The calves from the cows of both groups were born underweight with metabolic acidosis in group I and compensated acid-alkaline balance in group II. Changes in proteins, lipids, i.e. compounds produced by the liver were found to be the most dynamic and the most pronounced in calves from group I. The calves from this group were also much slower to reach the physiological norms of adult cows. The conclusions drawn are as follows: 1. Systemic acidosis distinctly inhibits the concentration of the compounds produced by the liver; 2. The diet containing an excess of and starch, though it does not affect the acid-alkaline balance, does lead to liver dysfunction; 3. Within one month the calves failed to reach the normal functional performance of the liver of adult cows. PMID:3448604
Janiak, T; Koziorowska, S; Grzegorzak, B; Nicpo?, J; Miernik, A; Zglejszewski, J
Poor dairy cow hygiene has been consistently associated with elevated somatic cell count (SCC) and the risk of subclinical mastitis. The objective of this study was to determine the associations between dairy cow standing and lying behavior, barn hygiene, cow hygiene, and the risk of experiencing elevated SCC. Lactating Holstein dairy cows (n=69; 86 ± 51 DIM; parity: 2.0 ± 1.2; means ± SD), kept in 1 of 2 groups, were monitored over a 4-mo period. Each group contained 61 ± 1 (mean ± SD) cows over the study period; complete data were obtained from 37 and 32 animals within each respective group. Cows were housed in a sand-bedded, freestall barn with 2 symmetrical pens, each with a free cow traffic automatic milking system. To vary barn hygiene, in 4 consecutive 28-d periods, alley manure scrapers in each of the 2 pens were randomly assigned to frequencies of operation of 3, 6, 12, and 24 times per day. During the last 7 d of each period, cow hygiene (upper leg/flank, lower legs, and udder; scale of 1 = very clean to 4 = very dirty) and stall hygiene (number of 0.15×0.15-m squares contaminated with manure in a 1.20×1.65-m grid) were recorded. Standing and lying behavior of the cows were collected during those days using data loggers. Individual-cow SCC was recorded at the beginning and end of each 28-d period. Elevated SCC was used as an indicator of subclinical mastitis; incidence of elevated SCC was defined as having a SCC >200,000 cells/mL at the end of each 28-d period, when SCC was <100,000 cells/mL at the beginning of the period. Less frequent scraping of the barn alleys was associated with cows having poorer hygiene. Poor udder hygiene was associated with poor stall hygiene. Longer lying duration was associated with poor hygiene of the upper legs/flank and udder. Greater premilking standing duration was associated with poor udder hygiene and decreased frequency of lying bouts was associated with poor hygiene of the lower legs. Higher milk yield was associated with poor hygiene of the udder and lower legs; multiparous cows had poorer hygiene of the upper legs/flank and udder. Over the study period, 24 new cases of elevated SCC were detected. No associations existed for the risk of experiencing an elevated SCC with alley scraping frequency or cow behavior patterns. However, increased odds of occurrence of elevated SCC were noted for cows of lower milk yield as well as for multiparous cows. In summary, these results show that cow hygiene is affected by the standing and lying behavior of cows and by the cleanliness of the cow's environment. These findings emphasize the need for cows to be provided clean standing and lying environments. The results also show that frequent cleaning of barn alley floors will help improve cow hygiene. PMID:22884345
Devries, T J; Aarnoudse, M G; Barkema, H W; Leslie, K E; von Keyserlingk, M A G
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.
The review is based on a compiled data set from studies quantifying liver release of glucose concomitant with uptake of amino acids (AA) and other glucogenic precursors in periparturient dairy cows. It has become dogma that AAs are significant contributors to liver gluconeogenesis in early lactation, presumably accounting for the observed lack of glucogenic precursors to balance estimated glucose need. Until recently, there has been paucity in quantitative data on liver nutrient metabolism in the periparturient period. Propionate is the quantitatively most important glucogenic precursor throughout the periparturient period. However, the immediate post partum increment in liver release of glucose is not followed by an equivalent increment in propionate uptake, because of the lower rate of increment in feed intake compared with the rate of increment in requirements for milk synthesis. The quantitative data on liver metabolism of AA do not support the hypothesis that the rapid post partum increase in net liver release of glucose is supported by increased utilisation of AA for gluconeogenesis. Only alanine is likely to contribute to liver release of glucose through its role in the inter-organ transfer of nitrogen from catabolised AA. AAs seem to be prioritised for anabolic purposes, indicating the relevance of investigating effects of supplying additional protein to post partum dairy cows. Combining data from quantitative and qualitative experimental techniques on L-lactate metabolism point to the conclusion that the quantitatively most important adaptation of metabolism to support the increased glucose demand in the immediate post partum period is endogenous recycling of glucogenic carbon through lactate. This is mediated by a dual site of adaptation of metabolism in the liver and in the peripheral tissues, where the liver affinity for L-lactate is increased and glucose metabolism in peripheral tissues is shifted towards L-lactate formation over complete oxidation. PMID:23823867
Larsen, M; Kristensen, N B
Milk production in dairy cows has dramatically increased over the past few decades. The selection for higher milk yield affects the partitioning of available nutrients, with more energy being allocated to milk synthesis and less to physiological processes essential to fertility and fitness. In this study, the abundance of numerous milk metabolites in early and late lactation was systematically investigated, with an emphasis on metabolites related to energy metabolism. The aim of the study was the identification and correlation of milk constituents to the metabolic status of the cows. To investigate the influence of lactation stage on physiological and metabolic variables, 2 breeds of different productivity were selected for investigation by high-resolution nuclear magnetic resonance spectroscopy and gas chromatography-mass spectrometry. We could reliably quantify 44 different milk metabolites. The results show that biomarkers such as acetone and beta-hydroxybutyrate are clearly correlated to the metabolic status of the individual cows during early lactation. Based on these data, the selection of cows that cope well with the metabolic stress of early lactation should become an option. PMID:20338431
Klein, M S; Almstetter, M F; Schlamberger, G; Nürnberger, N; Dettmer, K; Oefner, P J; Meyer, H H D; Wiedemann, S; Gronwald, W
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...
The purpose of this study was to evaluate the diagnostic performance of a hand-held electronic glucometer (Precision Xtra; Abbott Diabetes Care Inc., Mississauga, ON, Canada) for cow-side use in dairy cattle. This device has been validated for measuring blood concentrations of ?-hydroxybutyrate in dairy cows. This study was designed to assess the accuracy of whole-blood glucose measurements from the glucose meter relative to a reference chemical analyzer in a diagnostic laboratory. Duplicate samples were taken from the same cows at the same time, into blood tubes with either the glycolysis-inhibiting preservative sodium fluoride (NaF) or without preservative. Glucometer readings were taken on whole blood with no preservative, and laboratory measurements were conducted on serum preserved with NaF. Blood samples were collected from cows between 3 wk before and 5 wk after calving, including during a glucose tolerance test conducted 1 wk before expected calving. Passing-Bablok and Bland-Altman data analyses were used to evaluate the performance of the glucometer relative to the laboratory results. A strong correlation was observed in 709 samples from 81 cows between the hand-held meter and serum from samples preserved with NaF (R(2)=0.95). Overall, 96% of measurements with the glucometer fell within the 95% confidence limits of analysis in the laboratory, although at higher-than-physiologic glucose concentrations (>5.2mmol/L) the glucometer tended to overestimate. The hand-held glucometer appears suitable for rapid measurement of glucose under field conditions in dairy cattle. PMID:23684029
Wittrock, J A M; Duffield, T F; LeBlanc, S J
Wheat grain (WG) is a unique cereal rich in easily fermentable starch and low in cation-anion difference (e.g. 5.3 mEq/100 g). The controlled prepartal dietary inclusion of WG, thus, has the potential to ease adapting the rumen microbes and papillae to the high-starch lactation diets, stimulate feed intake, reduce hypocalcaemia by reducing extracellular alkalinity and a moderate induction of bone resorption, and improve milk yield in periparturient cows. The primary objective was to determine the effects of prepartal feeding of WG compared to barley grain plus wheat bran on metabolic and productive criteria in periparturient Holstein cows. Twenty-four dry cows and 16 pregnant heifers were blocked based on parity and projected calving date and fed a prepartal diet containing either (i) ground WG (18% on a dry matter basis) or (ii) a conventional diet with ground barley grain and wheat bran or control diet, from 28-day prepartum until parturition. All cows were fed the control diet during 21-day postpartum. Prepartal dietary inclusion of WG increased prepartum feed intake, elevated blood glucose and attenuated hypocalcaemia at 7-day prepartum and 1-day postpartum, reduced urine pH, and increased milk fat percent and yield. Blood proteins at 7-day prepartum were higher and placenta tended to be expelled sooner in WG-fed cows than in other cows. Treatments did not affect milk protein, changes in body condition score; total time spent eating, ruminating and chewing; blood levels of urea nitrogen, cholesterol, and phosphorous, fecal pH, and calving difficulty. Therefore, the prepartal dietary use of WG proved effective in the simultaneous improvement of calcium and energy states, and thereby, in easing the metabolic transition from gestation into lactation in Holstein cows. PMID:19012605
Amanlou, H; Zahmatkesh, D; Nikkhah, A
The purpose of this study was to investigate variations in hepatic regulation of metabolism during the dry period, after parturition, and in early lactation in dairy cows. For this evaluation, cows were divided into 2 groups based on the plasma concentration of beta-hydroxybutyric acid (BHBA) in wk 4 postpartum (PP; group HB, BHBA >0.75 mmol/L; group LB, BHBA <0.75 mmol/L, respectively). Liver biopsies were obtained from 28 cows at drying off (mean 59 +/- 8 d antepartum), on d 1, and in wk 4 and 14 PP. Blood samples were collected every 2 wk during this entire period. Liver samples were analyzed for mRNA abundance of genes related to carbohydrate metabolism (pyruvate carboxylase, PC; phosphoenolpyruvate carboxykinase, PEPCK; citrate synthase, CS), fatty acid biosynthesis (ATP citrate lyase, ACLY) and oxidation (acyl-CoA synthetase long-chain, ACSL; carnitine palmitoyltransferase 1A, CPT 1A; carnitine palmitoyltransferase 2, CPT 2; acyl-coenzyme A dehydrogenase very long chain, ACADVL), cholesterol biosynthesis (3-hydroxy-3-methylglutaryl-coenzyme A synthase 1, HMGCS1), ketogenesis (3-hydroxy-3-methylglutaryl-coenzyme A synthase 2, HMGCS2), and of genes encoding the transcription factors peroxisome proliferator-activated receptor alpha (PPARalpha), peroxisome proliferator-activated receptor gamma (PPARgamma), and sterol regulatory element binding factor 1 (SREBF1). Blood plasma was assayed for concentrations of glucose, BHBA, nonesterified fatty acids, cholesterol, triglycerides, insulin, insulin-like growth factor-I, and thyroid hormones. In both groups, plasma parameters followed a pattern usually observed in dairy cows. However, changes were moderate and the energy balance in cows turned positive in wk 7 PP for both groups. Additionally, the energy balance and milk yield were similar for both groups after parturition onwards. Significant group effects were found at drying off, when plasma concentrations of triglycerides were higher in LB than in HB, and in wk 4 PP, when plasma concentrations of glucose and IGF-I were lower in HB than in LB. Similarly, moderate changes in mRNA expression of hepatic genes between the different time points were observed, although HB cows showed more adaptive performance than LB cows based on changes in mRNA expression of PEPCKc, PEPCKm, CS, CPT 1A, CPT 2, and PPARalpha. Part of the variation measured in this study was explained by parity. Significant Spearman rank correlation coefficients between the variables were not similar at each time point and were not similar between the groups at each time point, suggesting that metabolic regulation differs between cows. In conclusion, metabolic regulation in dairy cows is a dynamic system, and differs obviously between cows at different metabolic stages related to parturition. PMID:19389950
van Dorland, H A; Richter, S; Morel, I; Doherr, M G; Castro, N; Bruckmaier, R M
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;); Gerald B. Straley (University of British Columbia;)
Diseases of dairy cattle have adverse implications for both the dairy industry and animal welfare. Understanding adaptive immune response profiles of cattle on a national scale will provide insight into the potential for improving health and decreasing disease. The objectives of the present study were to evaluate immune response phenotypes of Holstein cows outside the peripartum period and to determine if antibody isotype bias to putative type 1 and type 2 test antigens is maintained. The cows, housed on commercial farms in 4 key dairy regions across Canada, were immunized with test antigens to measure their ability to mount cell-mediated immune responses (CMIR) and antibody-mediated immune responses (AMIR). Delayed-type hypersensitivity (DTH) was used as an indicator of CMIR and primary and secondary serum antibodies of the immunoglobulin (Ig) G1 and IgG2 isotypes were used to determine AMIR to the test antigens. Immune response phenotypes varied significantly among regions, herds, and cows. Cows in Alberta had significantly higher DTH responses and secondary responses to the type 2 test antigen than those in other regions. However, cows in Alberta had significantly lower primary antibody responses. It was found that Alberta had the lowest incidence of mastitis caused by Escherichia coli and Staphylococcus aureus compared with other regions. The IgG1/IgG2 antibody isotype ratio confirmed the nature of the test antigens. This was the first study to evaluate adaptive immune response profiles and disease incidence of dairy cows on a national scale and it therefore provides a glimpse of the current situation in Canada. PMID:23024454
Thompson-Crispi, Kathleen A; Mallard, Bonnie A
Scots pine as a model plant for studying the mechanisms of conifers adaptation to heavy metal action: 1. Effects of continuous zinc presence on morphometric and physiological characteristics of developing pine seedlings
Effects of zinc (50150 ?M ZnSO4) on seed germinability, morphometric and physiological characteristics of Scots pine (Pinus sylvestris L.) seedlings during first 6 weeks of their development were studied. Scots pine turned out to be rather sensitive to elevated\\u000a zinc concentrations. This was manifested in reduced seed germinability, root system growth retardation and suppression of\\u000a its development (primarily, reduction in
Yu. V. Ivanov; Yu. V. Savochkin; Vl. V. Kuznetsov
...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 Â§ 157.148 COW system: Evidence for inspections....
|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
The use of constraints to build quantitative physiological models and the application of these models to assist anaesthetists in decision making are discussed. A simple physiological model of human blood circulation and gas is given. It is represented in ...
F. Degeus E. Rotterdam S. Vandenneheuvel P. Vanemdeboas
Steller's sea cow, a giant sirenian discovered in 1741 and extinct by 1768, is one of the few megafaunal mammal species to have died out during the historical period. The species is traditionally considered to have been exterminated by 'blitzkrieg'-style direct overharvesting for food, but it has also been proposed that its extinction resulted from a sea urchin population explosion triggered by extirpation of local sea otter populations that eliminated the shallow-water kelps on which sea cows fed. Hunting records from eighteenth century Russian expeditions to the Commander Islands, in conjunction with life-history data extrapolated from dugongs, permit modelling of sea cow extinction dynamics. Sea cows were massively and wastefully overexploited, being hunted at over seven times the sustainable limit, and suggesting that the initial Bering Island sea cow population must have been higher than suggested by previous researchers to allow the species to survive even until 1768. Environmental changes caused by sea otter declines are unlikely to have contributed to this extinction event. This indicates that megafaunal extinctions can be effected by small bands of hunters using pre-industrial technologies, and highlights the catastrophic impact of wastefulness when overexploiting resources mistakenly perceived as 'infinite'. PMID:17148336
Turvey, S T; Risley, C L
The objectives were to characterize postpartum endometrial cytology and to determine the prevalence of subclinical endometrial inflammation and its impact on reproduction in beef cows. Samples for endometrial cytology (low-volume uterine lavage) were obtained from 135 of 137 Angus cows (2-87d postpartum) in northern Minnesota, 26d before breeding started. Agreement between examiners for subjective inflammation scores was very high (kappa=0.971); the correlation between these scores and PMN counts was high (r=0.83; P<0.001), validating subjective categorization. The proportion of PMN and large mononuclear cells (principally macrophages) declined with postpartum interval (P<0.001), whereas small mononuclear cells were consistently present (and not significantly affected by postpartum interval). Pregnancy rate to fixed-time AI was 29% and overall pregnancy rate was 89%. There was no association between cell type and ultimate pregnancy status or day of conception (P>0.10). Although inflammation later in the postpartum period apparently impaired subsequent reproduction in dairy cows, in cows >50 d postpartum at sample collection in the present study, no cytological parameter significantly predicted final pregnancy status or day of conception. Previous twinning increased the risk of subclinical endometritis (P=0.02), but not the probability of becoming pregnant (P=0.14). In conclusion, we inferred that beef cows had the ability to clear uterine inflammation after resumption of ovarian cyclicity. PMID:18992934
Santos, N R; Lamb, G C; Brown, D R; Gilbert, R O
The objective of this experiment was to evaluate the effects of glucose infusion on serum concentrations of glucose, insulin, and progesterone (P4), as well as mRNA expression of hepatic CYP2C19 and CYP3A4 in nonlactating, ovariectomized cows in adequate nutritional status. Eight Gir × Holstein cows were maintained on a low-quality Brachiaria brizantha pasture with reduced forage availability, but they individually received, on average, 3 kg/cow daily (as fed) of a corn-based concentrate from d -28 to 0 of the experiment. All cows had an intravaginal P4-releasing device inserted on d -14, which remained in cows until the end of the experiment (d 1). On d 0, cows were randomly assigned to receive, in a crossover design containing 2 periods of 24h each (d 0 and 1), (1) an intravenous glucose infusion (GLUC; 0.5 g of glucose/kg of BW, over a 3-h period) or (2) an intravenous saline infusion (SAL; 0.9%, over a 3-h period). Cows were fasted for 12h before infusions, and they remained fasted during infusion and sample collections. Blood samples were collected at 0, 3, and 6h relative to the beginning of infusions. Liver biopsies were performed concurrently with blood collections at 0 and 3h. After the last blood collection of period 1, cows received concentrate and returned to pasture. Cows gained BW (16.5 ± 3.6 kg) and BCS (0.08 ± 0.06) from d -28 to 0. Cows receiving GLUC had greater serum glucose and insulin concentrations at 3h compared with SAL cohorts. No treatment effects were detected for serum P4 concentrations, although mRNA expression of CYP2C19 and CYP3A4 after the infusion period was reduced for cows in the GLUC treatment compared with their cohorts in the SAL treatment. In conclusion, hepatic CYP3A4 and CYP2C19 mRNA expression can be promptly modulated by glucose infusion followed by acute increases in circulating insulin, which provides novel insight into the physiological mechanisms associating nutrition and reproductive function in dairy cows. PMID:23245955
Vieira, F V R; Cooke, R F; Aboin, A C; Lima, P; Vasconcelos, J L M
A retrospective longitudinal study was conducted aiming at determining specific risk factors associated with lameness in lactating dairy cattle. A total of 9762 cows from 165 Danish dairy herds was included in the analysis. The evaluated factors were: breed and parity of the cow, season in which calving took place, whether the cow had reproductive diseases, udder-related diseases, or metabolic\\/digestive
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...
SUMMARY - Metabolism trials were carried out with two groups of male, weaned Wistar rats to determine the nutritional value of the goat and cow milk protein. Diets contained 15% protein and 10% fat. The protein source was skimmed milk powder goat or cow milk, and the fat source was goat or cow milk fat. The food intake, growth rates
E. Ramos Morales; F. D. Carmona López; F. Gil Extremera; M. R. Sanz Sampelayo; J. Boza
Twenty-two cases of indigestion occurred in a 650-cow herd. Five cows had severe sand abomasal impaction, diagnosed by laparotomy. The pH of prepartum cows urine was < 6.0 and of sand 8.0. Feed showed a dietary cation-anion difference ? ?110 mEq/kg. After feeding management corrections, no more cases were diagnosed.
Melendez, Pedro; Krueger, Traci; Benzaquen, Mauricio; Risco, Carlos
Effects of dietary fat on milk compo- sition, particularly milk N, were evaluated in lactating dairy cows at two stages of lactation. Complete mixed diets contain- ing 0, 3.5, or 7% of the diet DM as animal fat were fed to 12 cows in a 3 × 3 Latin square. Cows were divided into two status categories based on stage
E. J. DePeters; S. J. Taylor; C. M. Finley; T. R. Famula
...2013-07-01 2013-07-01 false COW tank washing machines. 157.124 Section 157.124 Navigation...and Installation Â§ 157.124 COW tank washing machines. (a) COW machines must be permanently mounted in each cargo...
Summer heat stress lowers dairy cow feed intake and productive performance. Unless measures are taken to improve cow comfort this stress can also lead to animal health problems. Various cooling methods have been used successfully to alleviate this problem (Shultz 1986 and Armstrong 1993). These methods focus on increasing feed intake, while cooling the cow and the immediate environment around
Thomas A. Shultz; Paul Williams
The objective of this study was to determine the prevalence and intensity of gastrointestinal nematode, lungworm and liver fluke infection in culled cows in Ireland. Abomasa, colorectal contents and livers were collected from 30 to 68 culled beef and dairy cows during autumn 2002 and summer 2003, respectively. Ostertagia ostertagi were found in the abomasa of only three (10%) cows
T. M. Murphy; K. N. Fahy; A. McAuliffe; A. B. Forbes; T. A. Clegg; D. J. OBrien
Transmissible spongioform enchephalopathies (TSE's), include bovine spongiform encephalopathy (also called BSE or mad cow disease), CreutzfeldtJakob disease (CJD) in humans, and scrapie in sheep. They remain a mystery, their cause hotly debated. But between 1994 and 1996, 12 people in England came down with CJD, the human form of mad cow, and all had eaten beef from suspect cows. Current
2. COW HOUSE AT RIGHT FOREGROUND. There is an identical cow house opposite from the one pictured. In the background are: Robinson-Aiken Slave Building and Kitchens (SC-276) on left, and Robinson-Aiken Service Building and Stable (SC-275) on right. - Robinson-Aiken Cow House, 48 Elizabeth Street, Charleston, Charleston County, SC
|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
A new pacemaker that can adapt the heart rate in response to the patient's metabolic requirements has been developed. This pacemaker uses the QT interval as the indicator of physiological demand. Experience in five patients showed the rate response to exercise to be smooth and progressive and to return gradually to the basic paced rate after activity stopped. Physiological rate
R M Donaldson; K Fox; A F Rickards
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
The arthritogenic effect of dietary cows milk, egg albumin and soya milk were compared in Old English rabbits. The 12-week cows milk feeding regimen produced the highest incidence of significant joint lesions. Lesions were evident but mild at 5 weeks and the synovitis had resolved by 32 weeks. It is suggested that the transient nature of the synovitis may be
C. J. R. Welsh; A. C. Hanglow; P. Conn; R. R. A. Coombs
The present work describes the clinical and laboratory examination as well as the treatment of a 7-year-old local dairy breed cow presented with reduced appetite, decreasing milk yield and striking yellowish discoloured skin and mucosa. The laboratory examination revealed a high degree regenerative anaemia and hyperbilirubinaemia. The bovine haemotrophic mycoplasma species Mycoplasma wenyonii and 'Candidatus Mycoplasma haemobos' were detected in the blood by PCR. Treatment with oxytetracycline rapidly improved the general condition, and milk production was increased. In a follow-up study, blood samples of all 23 animals from the same herd were examined. Fifteen cows were found to be infected with both haemoplasma species, three animals were only infected with 'Candidatus Mycoplasma haemobos' and one animal only with Mycoplasma wenyonii. Two out of three tested calves were positive for 'Candidatus Mycoplasma haemobos'. Except for the above described anaemic cow, all other animals were clinically healthy. PMID:23242150
Baggenstos, R; Wenzinger, B; Meli, M L; Hofmann-Lehmann, R; Knubben-Schweizer, G
The scaling of respiratory metabolism with body size in animals is considered by many to be a fundamental law of nature. One apparent consequence of this law is the scaling of physiologic time with body size, implying that physiologic time is separate and distinct from clock time. Physiologic time is manifest in allometry relations for lifespans, cardiac cycles, blood volume circulation, respiratory cycle, along with a number of other physiologic phenomena. Herein we present a theory of physiologic time that explains the allometry relation between time and total body mass averages as entailed by the hypothesis that the fluctuations in the total body mass are described by a scaling probability density. PMID:23659904
West, Damien; West, Bruce J
Hebbian associative learning is a common form of neuronal adaptation in the brain and is important for many physiological functions such as motor learning, classical conditioning and operant conditioning. Here we show that a Hebbian associative learning synapse is an ideal neuronal substrate for the simultaneous implementation of high-gain adaptive control (HGAC) and model-reference adaptive control (MRAC), two classical adaptive
Jun-e Feng; Chung Tin; Chi-Sang Poon
SUMMARY Heterosis for maternal productivity in cross- bred Angus (A) by Milking Shorthorn (MS) cows was studied using 240 cows of A A, A X MS, MS A and MS X MS breed groups. Cows were born in the fall over a 5-year period. Calves were sired by llereford, Charolais and Red Poll bulls. Data from the first
M. C. Spelbring; T. G. Martin; K. J. Drewry
New data on food allergy has recently changed the management of children with cow's milk protein allergy (CMPA). The diagnosis of CMPA first requires the elimination of cow's milk proteins and then an oral provocation test following a standard diagnostic procedure for food allergy, without which the elimination diet is unjustified and sometimes harmful. Once the diagnosis is made, the elimination diet is strict, at least until the age of 9-12 months. If the child is not breastfed or the mother cannot or no longer wishes to breastfeed, the first choice is a formula based on extensive hydrolyzate of cow's milk (eHF), provided that its effectiveness has been demonstrated. When eHF fails, a formula based on amino acids is warranted. eHF based on rice protein hydrolysates is an alternative to cow's milk eHF. Infant formulas based on soy protein can be used after the age of 6 months, after verification of good clinical tolerance to soy. Most commonly, CMPA disappears within 2 or 3 years of life. However, the age of recovery varies depending on the child and the type of CMPA, and whether or not it is IgE-mediated, the first being more sustainable. When the child grows, a hospital oral provocation test evaluates the development of tolerance and, if possible, authorizes continuing the reintroduction of milk proteins at home. Some children with CMPA will tolerate only a limited daily amount of cow's milk proteins. The current therapeutic options are designed to accelerate the acquisition of tolerance, which seems facilitated by regular exposure to cow's milk proteins. PMID:21115329
Dupont, C; Chouraqui, J-P; de Boissieu, D; Bocquet, A; Bresson, J-L; Briend, A; Darmaun, D; Frelut, M-L; Ghisolfi, J; Girardet, J-P; Goulet, O; Hankard, R; Rieu, D; Rigo, J; Vidailhet, M; Turck, D
This paper reviews the concept of adaptation of human communities to global changes, especially climate change, in the context of adaptive capacity and vulnerability. It focuses on scholarship that contributes to practical implementation of adaptations at the community scale. In numerous social science fields, adaptations are considered as responses to risks associated with the interaction of environmental hazards and human
Barry Smit; Johanna Wandel
Background Intestinal malrotation is an incomplete rotation of the intestine. Failure to rotate leads to abnormalities in intestinal positioning and attachment that leave obstructing bands across the duodenum and a narrow pedicle for the midgut loop, thus making it susceptible to volvulus. One of the important differential diagnoses for malrotation is an allergy to cows milk. Several studies have described infants with surgical gastrointestinal diseases and cows milk allergy. However, to our knowledge, no study has reported infants with intestinal malrotation who have been symptomatic before surgery was performed and have been examined by allergen-specific lymphocyte stimulation test and food challenge tests with long-term follow-up. Case presentation The patient was a Japanese male born at 39 weeks of gestation. He was breast-fed and received commercial cows milk supplementation starting the day of birth and was admitted to our hospital at 6 days of age due to bilious vomiting. Plain abdominal radiography showed a paucity of gas in the distal bowel. Because we demonstrated malpositioning of the intestine by barium enema, we repositioned the bowel in a normal position by laparotomy. The patient was re-started on only breast milk 2 days post surgery because we suspected the presence of a cows milk allergy, and the results of an allergen-specific lymphocyte stimulation test showed a marked increase in lymphocyte response to kappa-casein. At 5 months of age, the patient was subjected to a cows milk challenge test. After the patient began feeding on cows milk, he had no symptoms and his laboratory investigations showed no abnormality. In addition, because the patient showed good weight gain and no symptoms with increased cows milk intake after discharge, we concluded that the present case was not the result of a cows milk allergy. At 1 year, the patient showed favorable growth and development, and serum allergy investigations revealed no reaction to cows milk. Conclusion When physicians encounter infants with surgical gastrointestinal disease, including intestinal malrotation, they should consider cows milk allergy as a differential diagnosis or complication and should utilize food challenge tests for a definitive diagnosis.
As the etiopathology of retained placenta is still not resolved in cattle, we compared the effects of protracted induction of parturition (PIP) and conventional induction of parturition (SIP) on placental maturation and the occurrence of retained placenta. PIP was induced in 13 cows by administration of 1.3 mg dexamethasone im twice daily between Days 268 and 273 of gestation and 40 mg dexamethasone im on Day 274 of gestation. For SIP, 10 cows received a single injection of 40 mg dexamethasone on Day 274 of gestation. A third group (SPON, n = 11) served as a nontreated control group. Within 2 hours after birth, two placentomes were extracted from the uterus and used for assessment of placental maturation by histology and immunohistochemistry. Incidence of retained placenta was lower (P < 0.05) in group SPON (9%) compared with groups PIP (54%) and SIP (70%). Staining with Masson's trichrome and pan-cytokeratin indicated a higher degree of atrophy and flatness of the maternal crypt epithelium in cows with physiological release of fetal membranes (REL) compared with cows with retained placentae (RET). Staining with anti-caspase-3 ratified the observations as more apoptotic cells were detected in groups SPON and PIP compared with group SIP; however, data were not statistically significant. Additionally, the expressions of the potent vasodilators endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS) were evaluated. Both eNOS and iNOS were only expressed in chorionic tissue. Endothelin-1 (ET-1), a major vasoconstrictor, showed positive staining in maternal crypt epithelium and in chorionic epithelium. No differences were found for iNOS and eNOS and ET-1, neither among the experimental groups nor between RET and REL cows. These findings indicate that a PIP results in increased placental maturation, but does not influence the incidence of placental retention in cows. The expression of vasoactive substances does not seem to be related to the placental separation process. PMID:23683692
Hartmann, D; Bollwein, H; Honnens, A; Niemann, H; Rath, D; Pfarrer, C
Gonadotrophin releasing hormones have become widely used hormonal compounds in veterinary medicine, particularly with respect to bovine reproduction. The character and physiological actions of gonadotrophin releasing hormone are briefly reviewed and its clinical applications are summarized. The endocrinological research concerned with the use of gonadotrophin releasing hormone in the early postpartum period is discussed. Field trials which have been conducted to assess the effects of postpartum gonadotrophin releasing hormone administration on reproductive performance have varied widely in both design and interpretation of results. These experiments are reviewed, including the clinical trials using normal cows as well as those on cows with retained placenta.
Leslie, K. E.
The authors present a neonatal case of allergic colitis, which manifested the difficulty of spontaneous defecation and irregular\\u000a narrowing of distal rectum in contrast enema. Rectal suction biopsy showed positive acetylcholinesterase activity. These clinical,\\u000a radiological and histological findings were indistinguishable from Hirschsprungs disease. Gastrointestinal symptoms were\\u000a improved by the cessation of cows milk formula. The present findings may impact on
Masanobu Kawai; Akio Kubota; Shinobu Ida; Yukiyo Yamamura; Norikazu Yoshimura; Makoto Takeuchi; Masahiro Nakayama; Hiroomi Okuyama; Takaharu Oue; Hisayoshi Kawahara; Akira Okada
The full fracture histories of 50 children (30 girls and 20 boys, age range 3 to 13 years) who had avoided drinking cows milk for prolonged periods were compared with those in a birth cohort of more than 1,000 children from the same city. Children who avoided milk did not use calcium-rich food substitutes appropriately and had low dietary calcium
Ailsa Goulding; Jennifer E. P. Rockell; Ruth E. Black; Andrea M. Grant; Ianthe E. Jones; Sheila M. Williams
The selenium content of human milk, cow's milk and cow's milk infant formula were estimated by instrumental neutron activation analysis. The highest values were found in 3 samples of human colostrum (524865×10-9 g\\/g dry weight). There was a significant decrease with increasing time post partum. Mature human milk exhibited a selenium content of 230±79×10-9 g\\/g dry weight.
Ingrid Lombeck; K. Kasperek; B. Bonnermann; L. E. Feinendegen; H. J. Bremer
The concentrations of lactoferrin (Lf) in quarter milk from normal lactating cows and subclinical mastitic cows were measured to determine whether the Lf concentration in milk is influenced by the age of the cow, the stage of lactation, number of milk somatic cells and the presence of pathogens. Lf concentrations in 111 quarter milk samples from 28 normal lactating cows and 270 quarter milk samples from 198 subclinical mastitic cows were measured by means of a single radial immunodiffusion test. Lf concentrations (means +/- standard deviations; logarithmic form) in normal cows and subclinical mastitic cows were 2.23 +/- 0.39 and 2.70 +/- 0.39, respectively. The mean milk Lf concentration (log) in subclinical mastitic cows was significantly (p<0.01) higher than that in normal cows. The mean milk Lf concentration (log) in normal lactating cows aged 5 years was lower than those in normal lactating cows aged 2 years (p<0.01) and 3 years (p<0.05). The results showed that the milk Lf concentration (log) is associated with age of the dairy cow (one-way analysis of variance test, p<0.01). The mean milk Lf concentration (log) in the latter lactational period tended to be higher than those in the peak and middle periods. Milk Lf concentrations (log) tended to be proportional to the level of the somatic cell count (SCC) score. Mean milk Lf concentrations (log) in subclinical mastitic cows infected with Staphylococcus aureus and with other streptococci species were significantly (p<0.01) higher than those in cows infected with coagulase-negative staphylococci and with Corynebacterium bovis. PMID:12679560
Hagiwara, Sei-ichi; Kawai, Kazuhiro; Anri, Akira; Nagahata, Hajime
Bovine growth hormone (bGH) was administered to high-yielding Holstein cows fed a complete mixed ration ad libitum. Commencing on day 74 of lactation, 10 cows averaging 34.4 kg milk per day were divided into two groups and received a daily subcutaneous injection of bGH (51.5 IU/day) or a placebo. Injections were continued for an 11-day period and differences in lactational performance, nitrogen balance and estimated energy balance between the two groups were compared for the last 5 days of the preinjection and injection periods. Growth hormone resulted in increases of 9.5% in milk yield, 22.7% in milk fat yield, 14.5% in milk lactose yield and a 17.1% increase in milk energy secretion. Feed intake was slightly reduced (-4.3%, nonsignificant) while milk protein secretion and nitrogen balance were unchanged. Serum growth hormone levels in the bGH group were maintained at the higher concentrations of the normal physiological range during the injection period. By 48 hours following the last injection, declining bGH concentrations approached control values, and milk production decreased to preinjection values. Serum prolactin levels and plasma concentrations of free-fatty acids were slightly increased during the injection period in the bGH group. Growth hormone clearly enhances milk synthesis in the high-yielding dairy cow. PMID:7277044
Peel, C J; Bauman, D E; Gorewit, R C; Sniffen, C J
Adult female beef cattle found positive for stanozolol in the urine were investigated for liver pathology. In all the animals toxic hepatitis was found, including cholestasis, periportal fibrosis and inflammation, focal necrosis and blood filled lacunae. As no clinical data of the cows were available, apart from the history of illegal stanozolol abuse, it is not possible to attribute all
M. J. Groot
Examines the design process, fabrication of settings and production of Boucicault's 19th century melodrama using a large (10' by 16') fiberglass cow on a turntable. The setting called for multiple locations ranging from a cottage to cliff tops and a ship's dock. Computer CAD Photoshop modeling used for previsualization and special construction techniques were used to create acting areas inside
Patrick Michael Finelli; Jason Winfield
|Proposes the science demonstration of dissecting a cow's eye to integrate biology and physics in the study of optics and lenses. Reviews the anatomy of the eye, describes the visual process and covers topics as index of refraction of the cornea, microscopic receptors, the lens, and the retina. (MDH)|
Lapp, David R.; Keenan, James E.
Three pregnant cows were each orally challenged at 10 weeks of gestation with 600 sporulated oocysts of Neospora caninum. The number of oocysts was limited by those available. In concurrent bioassays, one oocyst per os infected each of two gerbils. Challenged cattle developed Neospora-specific antibody, cell proliferation and ?-interferon responses. N. caninum specific PCR demonstrated persisting infection in the brains
A. J Trees; M. M McAllister; C. S Guy; J. W McGarry; R. F Smith; D. J. L Williams
Much of the focus on ration evaluaton has been on herd production and health records and on feed analyses. However, these pieces of information must be evaluated in the context of the variety of factors that may affect the cows. An important part of evaluating a ration is actually assessing the fe...
WE wish to record the finding of considerable amounts of isopropyl alcohol in the blood, milk and rumen contents of cows suffering from acetonæmia, whereas there appears to be none present in normal animals. This means that the figures given hitherto for (beta-hydroxybutyric acid in the literature on that condition are probably misleading, as by most of the usual methods
Alex. Robertson; Christian Thin; Ann M. Stirling
Production diseases of the dairy cow are caused by a level of production inconsistent with nutrient intake, provision of an inadequate diet, an unsuitable environment, an inappropriate breeding policy or various combinations of these factors. Although the transition period of 3 weeks pre-calving until 3 weeks post-calving is associated with a peak incidence of production disease, the effects of these
F. J. Mulligan; M. L. Doherty
Influence of short-term road transport stress on blood parameters in cows Summary Blood parameter changes have been investigated after short-term road transport stress in 18 crossbred dairy cows in northwest of Iran. Cows were transported in 4 groups of four cows and one group of two cows in five different days. Each group was transported by truck up to a
RAMIN ALI-GHOLI; ASRI-REZAIE SIAMAK; MOHAMMADI DARYOUSH
SYNOPSIS. Temperature's pervasive effects on physiological systems are reflected in the suite of tempera- ture-adaptive differences observed among species from different thermal niches, such as species with dif- ferent vertical distributions (zonations) along the subtidal to intertidal gradient. Among the physiological traits that exhibit adaptive variation related to vertical zonation are whole organism thermal tolerance, heart function, mitochondrial respiration, membrane
GEORGE N. SOMERO
A field experiment was undertaken in northern Ontario in order to assess the magnesium status of beef cattle raised in the area. Magnesium status was assessed using several criteria including blood and urine magnesium levels, and bone biopsy samples. Eighteen groups each containing four pregnant Shorthorn beef cows were used. Each of the following three mineral feeds were offered to six groups throughout the experiment: a mineral feed without magnesium, a mineral feed containing 8% magnesium in the form of magnesium oxide and the third containing sequestered magnesium with a magnesium level of about a tenth of that in the mineral feed containing magnesium oxide. During the winter, when the cows were housed indoors, they were fed grass silage. Six groups, two of each mineral feed, remained indoors throughout the summer. The other 12 groups were turned out to pasture on May 25 and continued receiving the appropriate mineral feed. There were no differences in serum magnesium owing to magnesium-supplementation treatments observed at any time during any experiment. Serum magnesium levels fell drastically in all groups before the cows were released to pasture, implying that the hypomagnesaemic condition was attributable to the stress of yarding. The rate of recovery from hypomagnesaemia was slower in the cows released to pasture than in those kept indoors. Urine samples from cows returned to the pasture were indicative of low magnesium status. At the end of the experiment, the magnesium levels in the bones of the housed animals were higher than for those on pasture. In spite of severe cases of hypomagnesaemia, no clinical signs of this metabolic condition were observed.
Hidiroglou, M; Thompson, B K; Ho, S K; Proulx, J G
Callitrichids, South American primates including marmosets and tamarins, have evolved a unique physiology. Twins share a placenta during gestation and exchange stem cells, resulting in naturally occurring chimeric adults. Our study used a quantitative PCR-based assay to address whether this chimerism was restricted to blood and other cells of the hematopoietic lineage or whether it extended to other somatic tissues. These studies help to characterize species that have adapted evolutionarily to pervasive chimerism, with every individual healthy and unperturbed. This experiment of evolution offers insight into transplantation and histocompatibility, reproductive biology and behavior, and innate and adaptive immunity.
Sweeney, Carolyn; Ward, Joshua; Vallender, Eric J.
An experiment was conducted to test the hypothesis that the supplementation of crude protein (CP) results in rumen acidosis and increased histamine concentrations in dairy cows. Six ruminally fistulated, non-pregnant dry cows were fed three experimental rations in a replicated 3 × 3 Latin square design. The CP contents in the low-CP, the high rumen undegradable protein (high-RUP) and the high rumen degradable protein (high-RDP) rations were 112, 259 and 266 g/kg dry matter (DM) respectively. The cows were fed 7.7 kg DM of the concentrates and 2.7 kg DM of rice straw. High levels of RDP in the ration significantly increased the ammonia, total volatile fatty acid (VFA) and histamine concentrations in the rumen fluid. However, supplemental CP, whether degradable or undegradable, did not significantly affect the pH of rumen fluid. Plasma urea nitrogen concentration was higher in both high-RDP and high-RUP in relation to cows fed the low-CP ration. The rise in ruminal histamine concentrations was physiologically non-relevant, most likely because rumen pH was not affected by supplemental CP at the installed level of DM intake. Therefore, it can be concluded that the issue of supplemental CP, rumen pH and ruminal histamine concentrations has not yet been settled. Further research is warranted to understand these relationships. PMID:21366715
Pilachai, R; Schonewille, J Th; Thamrongyoswittayakul, C; Aiumlamai, S; Wachirapakorn, C; Everts, H; Hendriks, W H
The periparturient period presents major physiological challenges for the dairy cow. It is a period that is affected by metabolic stressors, major changes in endocrine status, and altered immune function, which together result in an increased risk of disease. Immunological, hematological, and metabolic profiles from the periparturient period of heifers (primipara) were compared with those of cows (pluripara) to test the hypothesis that at the time of calving they have qualitatively different peripheral blood profiles. Blood samples were collected from 22 Holstein-Friesian animals on 3 occasions: approximately 2 wk before calving, within 24h after calving, and approximately 2 wk after calving. Quantitative PCR was used to measure the expression of a selected set of cytokines and receptors by peripheral blood leukocytes. Additional analyses included hemoglobin concentration, red cell, platelet and white cell counts (total and differentiated), and clinical diagnostic biochemical profiles. Total leukocyte counts, neutrophils, and lymphocytes were higher in heifers than cows before calving and within 24h after calving. Alkaline phosphatase was consistently higher in heifers than cows and several significant differences were observed between the 2 groups with regards to cytokine and cytokine-receptor mRNA expression. The results warrant further investigation from the perspective of identifying risk factors for metabolic and parturient disease in dairy cattle. PMID:23462170
Jonsson, N N; Fortes, M R S; Piper, E K; Vankan, D M; de Cisneros, J Prada J; Wittek, T
. 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
Four ruminally lactating Holstein cows averaging 602+/-25 kg of body weight and 64+/-6 d in milk at the beginning of the experiment were randomly assigned to a 4 x 4 Latin square design to determine the effects of feeding whole flaxseed and calcium salts of flaxseed oil on dry matter intake, digestibility, ruminal fermentation, milk production and composition, and milk fatty acid profile. The treatments were a control with no flaxseed products (CON) or a diet (on a dry matter basis) of 4.2% whole flaxseed (FLA), 1.9% calcium salts of flaxseed oil (SAL), or 2.3% whole flaxseed and 0.8% calcium salts of flaxseed oil (MIX). The 4 isonitrogenous and isoenergetic diets were fed for ad libitum intake. Experimental periods consisted of 21 d of diet adaptation and 7 d of data collection and sampling. Dry matter intake, digestibility, milk production, and milk concentrations of protein, lactose, urea N, and total solids did not differ among treatments. Ruminal pH was reduced for cows fed the CON diet compared with those fed the SAL diet. Propionate proportion was higher in ruminal fluid of cows fed CON than in that of those fed SAL, and cows fed the SAL and CON diets had ruminal propionate concentrations similar to those of cows fed the FLA and MIX diets. Butyrate concentration was numerically higher for cows fed the SAL diet compared with those fed the FLA diet. Milk fat concentration was lower for cows fed SAL than for those fed CON, and there was no difference between cows fed CON and those fed FLA and MIX. Milk yields of protein, fat, lactose, and total solids were similar among treatments. Concentrations of cis-9 18:1 and of intermediates of ruminal biohydrogenation of fatty acids such as trans-9 18:1 were higher in milk fat of cows fed SAL and MIX than for those fed the CON diet. Concentration of rumenic acid (cis-9, trans-11 18:2) in milk fat was increased by 63% when feeding SAL compared with FLA. Concentration of alpha-linolenic acid was higher in milk fat of cows fed SAL and MIX than in milk of cows fed CON (75 and 61%, respectively), whereas there was no difference between FLA and CON. Flaxseed products (FLA, SAL, and MIX diets) decreased the n-6 to n-3 fatty acid ratio in milk fat. Results confirm that flax products supplying 0.7 to 1.4% supplemental fat in the diet can slightly improve the nutritive value of milk fat for better human health. PMID:20630232
Côrtes, C; da Silva-Kazama, D C; Kazama, R; Gagnon, N; Benchaar, C; Santos, G T D; Zeoula, L M; Petit, H V
The effect of heat stress on changes in milk production, rectal temperature, respiratory rate and blood chemistry was evaluated in three groups of six mature Holstein, Jersey and Australian Milking Zebu (AMZ) dairy cows. These animals were subjected to a cool environment when the mean temperature-humidity index (THI) was 72+/-1.4 (dry bulb temperature of 22.2-24.4 degrees C and relative humidity of 100-60%) during the month of December. This experiment was repeated during the hotter month of July of the following year, when the mean THI was 93+/-3.1 (dry bulb temperature of 35.6-43.9 degrees C and relative humidity 95-35%). Holstein cows produced more (p <0.01) milk than AMZ and Jersey cows during the cooler months of the year and all the cows were dry during the hotter months from June until September. Heat stress increased (p<0.01) rectal temperature and respiratory rate in all three breeds. Heat stress had no effect on blood pH in Holstein and AMZ cows but lowered (p <0.01) blood pH from 7.42 to 7.34 in Jersey cows. In addition, heat stress lowered (p <0.01) blood pCO2 (kPa), bicarbonate (HCO3, mmol/L), base excess (BE, mmol/L) and plasma chloride (Cl-, mmol/L) in all three breeds. The total haemoglobin (THb, g/dl) was elevated (p <0.01) in all three breeds when they were subjected to heat stress. Heat stress increased (p<0.01) oxygen saturation (O2SAT, %) in Jersey and AMZ cows but lowered it (p <0.01) in Holstein cows. On the other hand, heat stress increased (p <0.01)pO2 (kPa) in Holstein and Jersey cows but lowered it (p <0.01) in AMZ cows. Heat stress increased (p <0.01) plasma potassium (K, mmol/L) and calcium (Ca, mmol/L) only in Holstein and Jersey cows but lowered them (p<0.01) in AMZ cows. The plasma glucose (GLU, mmol/L) increased (p<0.01) with heat stress in Holstein and AMZ cows but decreased (p <0.01) in Jersey cows. Heat stress increased (p<0.01) plasma creatinine (CR, (mol/L) but lowered (p<0.01) plasma creatinine phosphokinase (CPK, IU/L), aspartate aminotransferase (AST, IU/L) and blood urea nitrogen (BUN, mmol/L) in all three breeds. These results indicate that heat-stressed Holstein and AMZ cows were able to maintain their acid-base balance with a marginal change in their pH of 0.02 when their rectal temperatures increased by 0.47 and 0.38 degrees C, respectively. When heat stress increased the rectal temperature in Jersey cows by 0.70 degrees C, the pH decreased (p<0.01) from 7.42 to 7.34. However, even with this decrease 0.08 the pH is still within the lower physiological limit of 7.31. PMID:15563029
Srikandakumar, A; Johnson, E H
Haemoglobins from mammals of sub-Arctic and Arctic species, as well as fetal human Hb, are all characterized by a significantly lower Delta H of oxygenation compared with the majority of mammalian haemoglobins from temperate species (exceptions are represented by some cold-resistant species, such as cow, horse and pig). This has been interpreted as an adaptive mechanism of great importance from a physiological point of view. To date, the molecular basis of this thermodynamic characteristic is still not known. In the present study, we show that binding of extra chloride (with respect to adult human Hb) ions to Hb would significantly contribute to lowering the overall heat of oxygenation, thus providing a molecular basis for the low effect of temperature on the oxygenation-deoxygenation cycle. To this aim, the oxygen binding properties of bovine Hb, bear (Ursus arctos) Hb and horse Hb, which are representative of this series of haemoglobins, have been studied with special regard to the effect of heterotropic ligands, such as organic phosphates (namely 2,3-diphosphoglycerate) and chloride. Functional results are consistent with a mechanism for ligand binding that involves an additional binding site for chloride ion. Analysis of computational chemistry results, obtained by the GRID program, further confirm the hypothesis that the reason for the lower Delta H of oxygenation is mainly due to an increase in the number of the oxygen-linked chloride-binding sites.
De Rosa, M Cristina; Castagnola, Massimo; Bertonati, Claudia; Galtieri, Antonio; Giardina, Bruno
The APS is pleased to announce the launch of the Living History of Physiology Project. The Society encourages the membership to consider interviewing senior physiologists at their institutions to provide a living history of physiology. The videos provided to date focus on the physiologistÃÂs training and career and their professional interactions.
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...
|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
...intramammary infusion (dry cows). 526.1696b Section...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...intramammary infusion (dry cows). (a) Specifications...calving. For use in dry cows only. Milk taken from cows...
Background. A neurosurgical laboratory training model is designed for trainees in microneurosurgery to learn to handle surgical microscopes and microneurosurgical instruments. The silicone injection of a fresh cadaveric cow cranium is an alternative to using a cadaveric human brain for becoming familiar with the cerebellopontine angle (CPA) via the retrosigmoid approach. To report an improved method for training in the CPA via the retrosigmoid approach, using a fresh cadaveric cow cranium injected with silicone. Methods. The material consists of a cadaveric cow brain injected with silicone. Preparation consists of irrigation of the major vessels followed by injection of silicone, coloured either red or blue. Results. A three-step approach was designed to simulate microneurosurgical dissection along with the cerebellopontine angle and to dissect cranial nerves emerging from the brain stem. Conclusion. This laboratory training model is useful in allowing trainees to gain experience with the use of an operating microscope and familiarity with the CPA via the retrosigmoid approach. The aim of this study was to develop a novel model and to adapt it to create a life-like neurosurgical training system. PMID:23458576
Turan Suslu, H; Ceylan, D; Tatarl?, N; H?cdonmez, T; Seker, A; Bahr?, Y; K?l?c, T
Honeylocust is being widely planted in urban en- vironments. The species is reputed to be well adapted for sur- vival in these locations, but nevertheless exhibits premature senescence, tissue damage and early mortality on urban sites. Despite ample rainfall or irrigation, the problem seems to be drought induced. Morphologic and physiologic drought stress resistance adaptations of honeylocust were evaluated. Small
Donald F. Potts; Lee P. Herrington
A successful pregnancy requires multiple adaptations of the mother's physiology to optimize fetal growth and development, to protect the fetus from adverse programming, to provide impetus for timely parturition and to ensure that adequate maternal care is provided after parturition. Many of these adaptations are organized by the mother's brain, predominantly through changes in neuroendocrine systems, and these changes are
Paula J. Brunton; John A. Russell
The beginning of lactation requires huge metabolic adaptations to meet increased energy demands for milk production of dairy cows. One of the adaptations is the mobilization of body reserves mainly from adipose tissue as reflected by increased plasma nonesterified fatty acid (NEFA) concentrations. The capacity of the liver for complete oxidation of NEFA is limited, leading to an increased formation of ketone bodies, reesterification, and accumulation of triglycerides in the liver. As the skeletal muscle also may oxidize fatty acids, it may help to decrease the fatty acid load on the liver. To test this hypothesis, 19 German Holstein cows were weekly blood sampled from 7wk before until 5wk after parturition to analyze plasma NEFA concentrations. Liver biopsies were obtained at d 3, 18, and 30 after parturition and, based on the mean liver fat content, cows were grouped to the 10 highest (HI) and 9 lowest (LO). In addition, muscle biopsies were obtained at d -17, 3, and 30 relative to parturition and used to quantify mRNA abundance of genes involved in fatty acid degradation. Plasma NEFA concentrations peaked after parturition and were 1.5-fold higher in HI than LO cows. Muscle carnitine palmitoyltransferase 1? and ? mRNA was upregulated in early lactation. The mRNA abundance of muscle peroxisome proliferator-activated receptor ? (PPARG) increased in early lactation and was higher in HI than in LO cows, whereas the abundance of PPARA continuously decreased after parturition. The mRNA abundance of muscle PPARD, uncoupling protein 3, and the ?-oxidative enzymes 3-hydroxyacyl-coenzyme A (CoA) dehydrogenase, very long-chain acyl-CoA dehydrogenase, and 3-ketoacyl-CoA was greatest at d 3 after parturition, whereas the abundance of PPAR? coactivator 1? decreased after parturition. Our results indicate that around parturition, oxidation of fatty acids in skeletal muscle is highly activated, which may contribute to diminish the fatty acid load on the liver. The decline in muscle fatty acid oxidation within the first 4wk of lactation accompanied with increased feed intake refer to greater supply of ruminally derived acetate, which as the preferred fuel of the muscle, saves long-chain fatty acids for milk fat production. PMID:23910553
Schäff, C; Börner, S; Hacke, S; Kautzsch, U; Sauerwein, H; Spachmann, S K; Schweigel-Röntgen, M; Hammon, H M; Kuhla, B
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)
This study gives a comprehensive survey on 20 cows with vagus indigestion due to cranial functional stenosis (failure of omasal transport). The most important clinical findings were distension of the entire lateral abdominal wall on the left side and partially of the right ventral area as well, severely distended rumen, reduced or missing appetite and reduced defaecation. Nine animals had bradycardia. The dominant laboratory findings were increased concentrations of total protein and fibrinogen. Sixteen cows were slaughtered at the clinic. Six of these had signs of peritonitis in the cranial part of the abdomen, which had started from foreign body peritonitis. Six cows had abscesses between reticulum and liver, also starting from a foreign body, one cow had one isolated abscess in the liver and one cow severe fatty degeneration of the liver. In 2 cows no pathological changes could be found on the occasion of slaughter. PMID:2383226
Braun, U; Hausammann, K; Oertle, C
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.
Lettat, Abderzak; Benchaar, Chaouki
Subacute ruminal acidosis (SARA) is a condition where the pH of the rumen becomes abnormally acidic because of increased and altered production of volatile fatty acids. The objective of this experiment was to determine how a SARA challenge affects total mixed ration selection in dairy cows. In this study, 8 multiparous, lactating, ruminally cannulated Holstein cows were given a choice between a long-forage-particle-size diet with slow-fermenting starch (LC) and a short-forage-particle-size diet with fast-fermenting starch in a crossover design. Cows were allowed to adapt to this feeding scheme and were then subjected to a rumen challenge to induce a bout of SARA. The rumen challenge successfully decreased rumen pH and altered rumen volatile fatty acid profiles. Daily average rumen pH decreased from 6.02 to 5.77, and average minimum rumen pH decreased from 5.59 to 5.28. In addition, following the rumen challenge, concentrations of acetate, butyrate, and valerate, and acetate-to-propionate ratio increased. In response to the rumen challenge, intake of LC increased from the baseline level of 18.1% of total daily dry matter intake to 38.3% for that day. During the first recovery day after the rumen challenge, LC intake moderated to 28.0% of total daily dry matter intake. On the second recovery day, LC intake returned to baseline levels at 18.6%. These results indicate that cows are able to alter their diet preference for higher physically effective fiber and slower starch fermentability during a bout of SARA and that they can effectively fully recover from this type of SARA within 72h when appropriate diets are available. PMID:23932130
Maulfair, D D; McIntyre, K K; Heinrichs, A J
A competitive environment forces the farmer constantly to adopt new and more-intensive production methods aiming at lowering costs and increasing yields. At debate is whether this intensification of production has an adverse impact on animal health and welfare. We investigated this issue by using cointegration analysis (a new tool used in time series analysis). We introduce cointegration analysis by applying the method in an epidemiological study of dairy-cow mortality. Two long-run epidemiological relations are identified:(i) a physiological relation (where increasing consumption of concentrates corresponded to increasing milk yield and mortality) and (ii) a physical relation (which illustrated that higher mortality was closely related to a higher growth rate of the average herd size, current investments in dairy farming, and higher milk yield). We concluded that a higher level of physiological stress due to higher yield and concentrate consumption has led to increased mortality. Furthermore, changes in the physical environment due to increased mechanisation and larger herd sizes have contributed to less attention per cow and increased mortality. PMID:10551429
Nørgaard, N H; Lind, K M; Agger, J F
Twenty-two cases of indigestion occurred in a 650-cow herd. Five cows had severe sand abomasal impaction, diagnosed by laparotomy. The pH of prepartum cows' urine was < 6.0 and of sand 8.0. Feed showed a dietary cation-anion difference < or = -110 mEq/kg. After feeding management corrections, no more cases were diagnosed. PMID:17987969
Melendez, Pedro; Krueger, Traci; Benzaquen, Mauricio; Risco, Carlos
ABSTRACT Effects of herd, sire, season, body height, BW, age at calving, and metritis on future performance,of first lactation cows were evaluated in eight commercial Israeli Holstein herds. Short, heavy first lactation cows,had an odds ratio of 3.1 of incidence of metritis at calving com- pared with all othefirst lactation cows were measured,at wk 1 postpartum. Sire, herd, age, height,
Oded Markusfeld; Ephraim Ezra
In order to describe the normal bacterial flora in vaginas of Criollo Limonero cows, 51 healthy multiparous cows, at least\\u000a 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\\u000a tests. Out of 102 swabs, bacterial growth was obtained in 55 (53.9%) while the
Sunny Zambrano-Nava; Julio Boscán-Ocando; Jexenia Nava
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
Biological fluids (milk and serum/plasma) and cheese whey milk-derived fluid contain numerous molecules, especially amino acids and proteins. Therefore, the purpose of this study was to find out whether cheese whey (n:6), cow milk (n:6) and its blood (n=6) have adropin, nesfatin-1, apelin-12, ghrelins and salusin peptides. Adropin, nesfatin-1, apelin-12 concentrations were measured by ELISA, whereas ghrelin and salusin concentrations were measured by EIA methods. It was found that adropin, nesfatin-1, apelin-12, des-acylated ghrelin and salusins in cheese whey were higher than in the corresponding milk peptides and plasma of dairy cows, with the exception of salusin alpha and acylated ghrelin in milk being the same than that of the corresponding cheese whey concentration and plasma of dairy cows. A correlation was also found between milk peptides and cheese whey, as also with plasma of dairy cows. The data suggest that peptides in cow milk might be an important and nutritious food for (neonatal) calves and human diet due to their biological and physiological properties. PMID:23454173
The percentage of dairy cows that were mated and became pregnant during a 42 day breeding period was not significantly different when animals were routinely observed for estrus and mated when detected (71%, n = 56), inseminated at estrus following a single injection of cloprostenol (72%, n = 29), or inseminated at a fixed time after two cloprostenol treatments 11 days apart (69%, n = 28). However, 11 cows in the control group were not detected and mated during the breeding period and inclusion of these animals reduced the actual pregnancy rate to 60%. Results indicated that a controlled breeding program could have practical application in dairy herds but should be used with caution. Practitioners must evaluate management programs and decide, in consultation with the herdsman, if the introduction of controlled breeding technology might be advantageous.
King, G. J.; Burnside, E. B.; Curtis, R. A.
|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
Background: Exposure to some environmental agent such as different nutrition and contact with allergens may have a role in developing multiple sclerosis (MS). The present study was aimed to evaluate the cow's milk allergy (CMA) in MS patients compared to healthy controls. Materials and Methods: Between March 2012 and July 2012, 48 MS patients were selected and compared with 48 healthy subjectsto assess the frequency of CMA in MS patients compared to healthy control. Cow's milk specific immunoglobin E (IgE) was determined by Immuno CAP. Sex and the frequency of CMA were compared between study groups by Chi-square test. Results: Total of 96 subjects were assessed (22% male and 78% female). The mean age of the study subjects was 30.8 ± 6.6 years. Mean age of case and control groups was 30.7 (±6.9) versus 30.9 ± 6.3, respectively (P value = 0.83). There were no detection of cow's milk specific IgE in serum of MS patients and healthy subjects. Conclusion: There was no difference between MS and healthy subjects regarding CMA.
Ashtari, Fereshteh; Jamshidi, Fatemeh; Shoormasti, Raheleh Shokouhi; Pourpak, Zahra; Akbari, Mojtaba
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
Fitzpatrick, Kathleen A.
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.
A programmable physiological infusion device and method are provided wherein a program source, such as a paper tape, is used to actuate an infusion pump in accordance with a desired program. The system is particularly applicable for dispensing calcium in ...
W. H. Howard D. R. Young R. R. Adachi
A programmable physiological infusion device which is particularly applicable for dispensing calcium in a variety of waveforms. The device utilizes a program source such as a paper tape together with an automatically actuated infusion pump. The device pro...
W. H. Howard D. R. Young R. R. Adachi
Among trans fatty acids, trans-10,cis-12 CLA has negative effects on cow milk fat production and can affect human health. In high-yielding dairy cows, a shift from the trans-11 to the trans-10 pathway of biohydrogenation (BH) can occur in the rumen of cows receiving high-concentrate diets, especially when the diet is supplemented with unsaturated fat sources. In some but not all experiments, vitamin E has been shown to control this shift. To ascertain the effects of vitamin E on this shift of BH pathway, 2 studies were conducted. The first study explored in vitro the effects of addition of natural (RRR-?-tocopherol acetate) and synthetic (dl-?-tocopherol acetate) vitamin E. Compared with control and synthetic vitamin E, the natural form resulted in a greater trans-10/trans-11 ratio; however, the effect was very low, suggesting that vitamin E was neither a limiting factor for rumen BH nor a modulator of the BH pathway. An in vivo study investigated the effect of natural vitamin E (RRR-?-tocopherol) on this shift and subsequent milk fat depression. Six rumen-fistulated lactating Holstein cows were assigned to a 2×2 crossover design. Cows received 20-kg DM of a control diet based on corn silage with 22% of wheat, and after 2 wk of adaptation, the diet was supplemented with 600 g of sunflower oil for 2 more weeks. During the last week of this 4-wk experimental period, cows were divided into 2 groups: an unsupplemented control group and a group receiving 11 g of RRR-?-tocopherol acetate per day. A trans-10 shift of ruminal BH associated with milk fat depression due to oil supplementation of a high-wheat diet was observed, but vitamin E supplementation of dairy cows did not result in a reversal toward a trans-11 BH pathway, and did not restore milk fat content. PMID:22901477
Zened, A; Troegeler-Meynadier, A; Najar, T; Enjalbert, F
Editorial, April 2011. The author advocates for increased utilization of physiology in the biomedical field with examples of medical research in which physiology and doctors with physiological training played a crucial role.
Michael J Joyner (Mayo Clinic Anesthesiology)
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.
Torday, J. S.; Rehan, V. K.
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
Processor virtualization is a powerful technique that enables the run- time system to carry out intelligent adaptive optimizations like dynamic resource management. Charm++ is an early language\\/system that supports processor virtu- alization. This paper describes Adaptive MPI or AMPI, an MPI implementation and extension, that supports processor virtualization. AMPI implements virtual MPI processes (VPs), several of which may be mapped
Chao Huang; Orion Sky Lawlor; Laxmikant V. Kalé
We propose Homicide Adaptation Theory as a new explanation for why people kill. Multiple homicide mechanisms have evolved as effective context-sensitive solutions to distinct adaptive problems. Killing historically conferred large fitness benefits: preventing premature death, removing cost-inflicting rivals, gaining resources, aborting rivals' prenatal offspring, eliminating stepchildren, and winnowing future competitors of one's children. Homicidal ideation is part of evolved psychological
Joshua D. Duntley; David M. Buss
Background In the study of associations between genomic data and complex phenotypes there may be relationships that are not amenable to parametric statistical modeling. Such associations have been investigated mainly using single-marker and Bayesian linear regression models that differ in their distributions, but that assume additive inheritance while ignoring interactions and non-linearity. When interactions have been included in the model, their effects have entered linearly. There is a growing interest in non-parametric methods for predicting quantitative traits based on reproducing kernel Hilbert spaces regressions on markers and radial basis functions. Artificial neural networks (ANN) provide an alternative, because these act as universal approximators of complex functions and can capture non-linear relationships between predictors and responses, with the interplay among variables learned adaptively. ANNs are interesting candidates for analysis of traits affected by cryptic forms of gene action. Results We investigated various Bayesian ANN architectures using for predicting phenotypes in two data sets consisting of milk production in Jersey cows and yield of inbred lines of wheat. For the Jerseys, predictor variables were derived from pedigree and molecular marker (35,798 single nucleotide polymorphisms, SNPS) information on 297 individually cows. The wheat data represented 599 lines, each genotyped with 1,279 markers. The ability of predicting fat, milk and protein yield was low when using pedigrees, but it was better when SNPs were employed, irrespective of the ANN trained. Predictive ability was even better in wheat because the trait was a mean, as opposed to an individual phenotype in cows. Non-linear neural networks outperformed a linear model in predictive ability in both data sets, but more clearly in wheat. Conclusion Results suggest that neural networks may be useful for predicting complex traits using high-dimensional genomic information, a situation where the number of unknowns exceeds sample size. ANNs can capture nonlinearities, adaptively. This may be useful when prediction of phenotypes is crucial.
HANSEN,~ENELOPE A., AND K.B. ROBERTS. Human situ- ations: a course introducing physiology to medical students. Am. J. Physiol. 261 (Adv. Physiol. Educ. 6): S7-Sll, 1991.-A block course of 12 days is described. It is considered to be appropriate for both physiologically naive and sophisticated students en- tering either a traditional or a problem-based curriculum. It is adaptable for medical schools
PENELOPE A. HANSEN; K. B. ROBERTS
Background Cows milk allergy is the most common food allergy in young children. In areas outside the United States, milk from other mammals has been studied as a possible and desirable alternative for children with cows milk allergy. Objectives We chose to further investigate water buffalos milk as an alternative for cows milk allergic children in the United States. Methods Children with cows milk allergy were skin prick tested with water buffalos milk. Additionally, subjects were followed clinically for 1 year after the test to determine how many of the subjects had persistent cows milk allergy. Results In total, 30 children, age 8 months to 8 years, were skin prick tested to water buffalos milk with 73% (22/30) having a positive test. All children with a negative water buffalos milk skin test also had a negative cows milk skin test. In follow-up, most (7 of 8) of the children with a negative skin prick test (SPT) to water buffalos milk were found to have outgrown their cows milk allergy. In comparison, all of the subjects with a positive skin test to water buffalos milk had persistent cows milk allergy. After adjusting for this, we determined that 96% (22/23) of the children with persistent cows milk allergy were positive on skin testing to water buffalos milk. Conclusions In this population, the vast majority of children with persistent cows milk allergy were positive on skin prick testing to water buffalos milk. These results indicate that water buffalos milk is unlikely to be a successful alternative for children with cows milk allergy.
Sheehan, William J.; Gardynski, Andrea; Phipatanakul, Wanda
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
Use of rubber flooring in dairies has become popular because of perceived cow comfort. The objective of this longitudinal study was to evaluate locomotion, health, production, and immunity over the first 180d of each of the 1st and 2nd lactations of cows assigned to free-stall housing with either r...
...MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Cow Operations...to pass the inspections under Â§ 157.140 are recorded in the Crude Oil Washing Operations and Equipment Manual approved...
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...
Abstract Two beef cows were presented with a history of anorexia and abdominal pain. Both cows were euthanized. Necropsy revealed the presence of a segmental area of ulceration, necrosis, and intraluminal blood clots in the jejunum. Jejunal hemorrhage syndrome is an emerging disease and has not been reported previously in beef cattle.
Prolonged postpartum acyclicity in suckled beef cows reduces the calf crop, and causes economic loss to beef cattle producers. Once anterior pituitary LH stores have been replenished between Days 15 and 30 post partum in suckled beef cows, methods to initiate cyclicity include non-hormonal methods such as weaning of calves (either complete, temporary or partial), or exposure to bulls, and
Y. Yavas; J. S. Wallon
The objective of this study was to determine effects of monensin on ovarian follicular development and re- productive performance in postpartum dairy cows. Forty-eight multiparous Holstein cows were randomly assigned to receive either a control total mixed ration (n = 24) or the same diet plus 22 mg of monensin\\/kg (n = 24) from 21 d before anticipated calving until
S. K. Tallam; T. F. Duffield; K. E. Leslie; R. Bagg; P. Dick; G. Vessie; J. S. Walton
Background: Cow's milk is one of the most common food allergens in children. Limited information is available on the prevalence of reactivity to a related food source, beef. The purposes of this study were to examine the prevalence of symptomatic sensitivity to beef in a selected pediatric population and to determine the frequency of concomitant reactivity to cow's milk and
Sabine J. Werfel; Sara K. Cooke; Hugh A. Sampson
Mean plasma fibrinogen levels were determined in 133 normal calves, bulls, non-pregnant and pregnant cows. These were 508, 505, 660, and 581 mg per 100 ml of plasma respectively. The levels in 233 sick cows were often greatly increased. This appeared to be related to inflammation and tissue destruction. Lower than normal levels were sometimes seen in liver disease and terminal states.
McSherry, B. J.; Horney, F. D.; deGroot, J. J.
Twelve Holstein cows were matched into pairs after 7 days lactation. Each was fed 1 kg of grain concentrate per 3 kg milk and corn silage free choice. At 2 wk, one cow from each pair was maintained on this diet and the other was fed a protected tallow product mixed with the grain concentrate, 1 to 2, providing 25%
D. S. Kronfeld; S. Donoghue; J. M. Naylor; K. Johnson; C. A. Bradley
Our objectives were to determine if grazing dairy cows would respond to fishmeal supplementation and to determine if responses could be explained by stimula- tion of adipose tissue lipolysis. Thirty-four multiparous Holstein cows (25 ± 11 DIM) were supplemented with isonitrogenous concentrates containing either fishmeal or pelleted sunflower meal. On a dry matter (DM) basis, concentrates contained fishmeal (14.5%) or
G. F. Schroeder; G. A. Gagliostro
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
The purpose of this study was to ascertain 1) fatty infiltration of the liver in spontaneously ketotic cows and 2) the most appropriate blood components to aid diagnosis of ketotic fatty liver. Liver biopsies and blood samples were obtained under field conditions. Cows were divided into three groups (healthy, mildly ketotic, and severely ketotic) by their blood ketone body concentrations.
Y. Gröhn; L.-A. Lindberg; M. L. Bruss; T. B. Farver
Twenty multiparous Holstein cows in mid-lactation grazed pastures of four forage mixtures in a 13-week study repeated during two grazing seasons to determine if forage mixtures affected intake and productivity of lactating dairy cows. The forage mixtures were: 1) orchardgrass plus white clover (2...
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...
We report on a female patient affected by galactosemia in whom the diagnosis was obscured by the concomitant presence of manifestations suggesting a cows milk intolerance. This case exemplifies the problems in reaching a correct diagnosis in patients with metabolic diseases.
The sea, or Steller's, cow (Hydromalis gigas Zimm.) belongs among the most amazing mammals. It was discovered by a participant in the famous Bering expedition of 1741-42, the naturalist G. Steller. It is one of the five species of the order of sea cows or...
V. G. Heptner
Identifying lame cows and quantifying the prevalence of lameness are important elements of cattle welfare assessment that are generally achieved by methods involving observations of each animal walking. There is no published method for assessing lameness in cows confined in tie-stalls. The objective of this study (car- ried out within the European Commission's Welfare Quality® project) was to develop a
K. A. Leach; S. Dippel; J. Huber; S. March; C. Winckler; H. R. Whay
Computers on wheels, or COWs, combine the wireless technology of today with the audio/visual carts of yesteryear for an entirely new spin on mobility. Increasingly used by districts with laptop computing initiatives, COWs are among the hottest high-tech sellers in schools today, according to market research firm Quality Education Data. In this
The kinetics of dry matter intake, raw milk yield, milk fat yield, and body weight of 140 treatment groups of cows reported in 37 articles published between 1959 and 1999 were collected in a database. The majority of these experiments were performed with Holstein- Friesian cows (primiparous: n = 51, multiparous: n = 89). Animals were fed with forages and
O. Martin; D. Sauvant
Groups of lactating cows and goats were used to examine americium-241 metabolism in dairy animals. Following either single oral or intravenous nuclide doses, samples of milk, urine, blood, and feces were taken over a 168-hr collection period and the americium concentrations were determined by gamma counting. Gastrointestinal uptake of americium by both cows and goats was estimated to be 0.014%
W. W. Sutton; R. G. Patzer; A. A. Mullen; P. B. Hahn; G. D. Potter
Holstein rumen-cannulated cows [n=7; initial body weight (BW) 640.56±71.43 kg] were fed a corn silage basal diet with 1 of 3 concentrates (C=control; P10=10% pigeon peas; P20=20% pigeon peas). Cows were randomly assigned to treatments in a replicated 3×3 Latin square and individually fed using Calan gates. Each experimental period was 21 d with 7 d for adaption and 14 d for sample collection. Ruminal fluid samples were taken the last day of each experimental period and analyzed for pH, ammonia, long-chain fatty acids, and volatile fatty acids (VFA). Consecutive a.m. and p.m. milk samples were taken during the last 2 wk of the 21-d period and analyzed for fat, protein, long-chain fatty acids, and somatic cell count. Dry matter intake (kg/d) was reduced during the second period and was greater for P10 diets. Milk protein was greater for cows fed P20 compared with P10. Energy-corrected milk was greater for cows fed the control diet compared with P10. Treatment had no effect on milk yield. Ruminal fluid pH decreased over sampling times; however, pH remained at or above 5.5. Diets did not affect ruminal fluid pH; however, pH was different for sampling periods. Ruminal ammonia decreased until 8h postfeeding at which time it peaked consistent with changes in ammonia concentrations that usually peak 3 to 5h postfeeding on diets high in plant proteins. Dietary treatments altered ruminal fluid VFA with reduced concentrations of acetate and greater concentrations of propionate for control diet, resulting in reduced acetate:propionate ratio. Isobutyrate exhibited an hour by treatment interaction, in which isobutyrate decreased until 8h postfeeding and then tended to be greater for P10 than for other treatments. Animals fed the P10 diet had greater concentrations of ruminal isovalerate. Ruminal cis-9,trans-11 and trans-10,cis-12 conjugated linoleic acid (CLA) isomers were not affected by dietary treatments. The P10 diet had greatest ruminal synthesis of cis-9,trans-11, but control cows had greatest ruminal synthesis of trans-10,cis-12. Milk CLA isomers were similar among treatments. Trends were observed for greater cis-9,trans-11 and trans-10,cis-12 for the P10 diet. Pigeon peas may be used as a protein supplement in dairy diets without affecting milk production, dry matter intake, or ruminal environment when they replace corn and soybean meal. PMID:20965347
Corriher, V A; Hill, G M; Bernard, J K; Jenkins, T C; West, J W; Mullinix, B G
This extensive Plant Physiology Information Website was created by Ross E. Koning, professor of biology at Eastern Connecticut State University. Dr. Koning provides links to lecture notes, lab exercises, and other resources for a variety of his courses including Biology of Plants, Plant Physiology, Principles of Biology, and more. In addition, the site offers a diverse assortment of other resources such as an Elementary Education Energy Workshop handout, a science fair project on lettuce seed germination, and related website links. The site also provides guidelines for CBE, APA, and MLA citation styles.
This journal has recently been made available online. The Japanese Society of Plant Physiologists, in combination with Oxford Journals Online, has posted recent issues of the journal Plant and Cell Physiology, an international journal covering original research in the fields of "physiology, biochemistry, biophysics, chemistry, molecular biology, cell biology and gene engineering of plants and micro-organisms." Online coverage includes full-text and abstracts from July 2000 to the present. Note that the electronic version of this journal is free through the end of 2000.
Inhibition of conidial germination of Bipolaris sorokiniana was tested using eight ethanolic plant extracts, ten aqueous plant extracts in combination with cow dung and five aqueous plant extracts in combination with cow urine. Hundred percent of conidial germination was inhibited with the application of ethanolic extracts of Adhatoda vasica (leaf) and Zingiber officinale (rhizome) at 2.5% concentration. After the treatment
Nargis Akhter; Ferdousi Begum; Shahidul Alam
GPS collars were used to describe the daily distribution patterns of cows and their calves from 18 to 60 days postpartum on pinyon juniper-shortgrass rangeland in central New Mexico. Eighteen, 3 year old cows and their calves were fitted weekly with GPS collars for seven consecutive weeks. Twenty da...
The development of infant formula with optimized protein quality and quantity has been, and still is, the subject of intense investigation. A better understanding of the protein composition of breast milk and infant needs in association with technological breakthroughs in cows milk fractionation, has led to the development of infant formulas with a protein content that is closer to that
P. Steenhout; P. Klassen; A. Donnet
Background: The present study was designed to compare the faecal microbiota and concentrations of faecal short-chain fatty acid and ammonia between healthy and cows milk protein allergic (CMPA) infants. Methods: The population comprised 92 infants aged 212 months who were nonallergic (n = 46) or diagnosed as having CMPA (n = 46). Faecal samples were analyzed by fluorescent in situ
Oscar C. Thompson-Chagoyan; Matteo Fallani; José Maldonado; José M. Vieites; Sheila Khanna; Christine Edwards; Joël Doré; Angel Gil
Fifteen normal dairy cows and 12 dairy cows with Johne's disease were monitored for expression of adhesion molecules on lymphocytes in blood and milk at parturition and at intervals up to 21 days postpartum. Using flow cytometric analysis, we examined expression of CD62L, CD11a and alpha4/beta7 on ...
SUMMARY Heterosis for maternal productivity was studied in crossbred Angus (A) Milking Shorthorn (MS) cows beginning with 240 fe- males of A A,A MS, MS X AandMS MS breed groups. Cows were born in the fall over 5 years. Calves were sired by Hereford, Charolais and Red Poll bulls. Traits were percent pregnant, percent calves born and
M. C. Spelbring; T. G. Martin; K. J. Drewry
The research conducted under this grant has addressed the area of Adaptive Steganography, covering the domains of data hiding, data embedding, and forensics. Key accomplishments include the development of an entirely new and novel framework for data hidin...
|Suggestions are presented for helping disabled individuals learn to use or adapt toothbrushes for proper dental care. A directory lists dental health instructional materials available from various organizations. (CB)|
Exceptional Parent, 1987
This is an informational resource for teachers and students. It contains descriptions and pictures of different biomes, examples of some of the plants that live there, and some of the adaptations those plants have.
Garden, Missouri B.
We studied dairy cows (n = 30) walking on concrete and on a soft, high-friction composite rubber surface to examine how flooring influenced gait and how this differed for cows with hoof lesions. Cows had hooves trimmed 9 wk after the trial and were classified as either with or without sole ulcers. Video recordings of the cows while walking were
F. C. Flower; A. M. de Passillé; D. M. Weary; D. J. Sanderson; J. Rushen
Summary. The progress of Staphylococcus aureus infection from inoculation to the early chronic stage was examined in 12 Israeli-Holstein cows (four primiparous and eight multiparous) for up to 48 d after inoculation. Before inoculation, the primiparous cows were free from any infection and the multiparous cows were infected by coagulase-negative staphylococci. Two quarters in each cow were inoculated intracisternally following
EZRA SHOSHANI; GABRIEL LEITNER; BOAZ HANOCHI; ARTHUR SARAN; NAHUM Y. SHPIGEL; AMIEL BERMAN
A total of 799 Holstein cows from 3 herds were ran- domly assigned at 37 ± 3 d in milk (DIM) to timed artificial insemination (AI) or insemination at detected estrus. Cows were presynchronized with injections of PGF2? at 37 and 51 DIM. At 65 DIM, cows received an injection of GnRH, followed 7 d later by PGF2?. Cows in
R. L. A. Cerri; J. E. P. Santos; S. O. Juchem; K. N. Galvão; R. C. Chebel
The efficacy of intramuscularly and intramammar- ily administered cefquinome was evaluated in ex- perimental Escherichia coli mastitis in dairy cows. Forty-seven multiparous, Israeli Holstein cows in early lactation that produced at least 25 L\\/d of milk were used, and 400 to 750 cfu of E. coli were infused into two healthy quarters of each cow. Cows were randomly assigned to
N. Y. Shpigel; D. Levin; M. Winkler; A. Saran; G. Ziv; A. Böttner
Twelve hundred ninety-six cows on 88 farms were alternately injected at calving with Levamisol or saline. Each farm was visited every 2nd wk from May to Octo- ber to administer treatments to cows that would calve prior to our next visit and to collect fecal grab samples from cows for worm egg counts. Production records were collected for each cow
Elliot Block; W. A. McDonald; B. A. Jackson
Two experiments were conducted with the objective of investigating the effects of rumen-protected methionine (RPMet) supplementation of metabolizable protein (MP)-deficient or MP-adequate but Met-deficient diets on dairy cow performance. Experiment (Exp.) 1 utilized 36 Holstein dairy cows blocked in 12 blocks of 3 cows each. Cows within block were assigned to one of the following dietary treatments: (1) MP-adequate diet [AMP; positive MP balance according to the National Research Council (2001) dairy model]; (2) an MP-deficient diet supplemented with 100g of rumen-protected Lys (RPLys)/cow per day (DMPL); and (3) DMPL supplemented with 24 g of RPMet/cow per day (DMPLM). Experiment 2 utilized 120 Holstein cows assigned to 6 pens of 20 cows each. Pens (3 per treatment) were assigned to one of the following dietary treatments: (1) AMP diet supplemented with 76 g of RPLys/cow per day (AMPL); and (2) AMPL (74 g of RPLys/cow per day) supplemented with 24 g of RPMet/cow per day (AMPLM). Each experiment lasted for 10 wk (2-wk adaptation and 8-wk experimental periods) following a 2-wk covariate period (i.e., a total of 12 wk). In Exp. 1, the MP-deficient diets decreased apparent total-tract nutrient digestibility but had no statistical effect on dry matter intake (DMI), milk yield, or milk fat percentage and yield. Compared with AMP, DMPL decreased milk protein content; both DMPL and DMPLM diets decreased milk protein yield. Urinary N losses and milk urea-N concentration were decreased by the MP-deficient diets compared with AMP. The ammonia emitting potential of manure from the MP-deficient diets was decreased by about 37% compared with that of AMP manure. Plasma Lys and Met concentrations were not affected by treatment, but concentrations of His, Thr, and Val were lower for the MP-deficient diets compared with AMP. In Exp. 2, the AMPLM diet had lower milk yield than AMPL due to numerically lower DMI; no other effects were observed in Exp. 2. In conclusion, feeding MP-deficient diets supplemented with RPLys and RPMet did not statistically decrease milk yield in dairy cows in Exp. 1. However, without RPMet supplementation, milk protein content was decreased compared with the MP-adequate diet. Other amino acids, possibly His, may limit milk production in MP-deficient, corn or corn silage-based diets. A summary of 97 individual cow data from trials in which MP-deficient diets were fed suggested the National Research Council (2001) model under-predicts milk yield in cows fed MP-deficient diets (MP balance of -20 to -666 g/d) in a linear manner: milk yield under-prediction [National Research Council (2001) MP-allowable milk yield, kg/d - actual milk yield, kg/d] = 0.0991 (±0.0905) + 0.0230 (±0.0003) × MP balance, g/d (R(2)=0.99). PMID:22916930
Lee, C; Hristov, A N; Heyler, K S; Cassidy, T W; Lapierre, H; Varga, G A; Parys, C
A case report of perforated duodenal ulcer in a ten year old Holstein cow is presented. On three occasions, sudden anorexia and rapidly progressing abdominal fluid distension were associated with metabolic alkalosis, hypochloremia and hypokalemia. Rumen fluid at the time of the second episode was acidic and contained an excessive amount of chloride ion. An abdominal mass dorsal to the abomasum involving the pylorus and several loops of small bowel was identified but not corrected at surgery. Necropsy confirmed a 1.5 cm diameter duodenal ulcer 6 cm distal to the pylorus.
Fatimah, I.; Butler, D. G.; Physick-Sheard, P. W.
Serum zinc concentrations have been determined in 28 healthy full-term Italian infants of both sexes at birth, as well as at 3 and at 5 months of age. Fourteen exclusively breast-fed infants who served as a control group were compared with 14 infants fed a cow's milk based adapted infant formula. No significant differences in serum zinc concentration between the
V. Vigi; R. Chierici; L. Osti; F. Fagioli; R. Reseazzi
Physiological changes related to lipid metabolism, behavior, and chemicals released in body exudates were studied during musth in the Asian elephant, Elephas maximus, as a case study. During musth, changes in serum testosterone and triglyceride concentrations followed similar patterns, with the former increasing sooner than the latter. Deviant behavior increased during changing androgen levels. The observed high concentrations of testosterone
L. E. L Rasmussen; Thomas E Perrin
Numerous plant microbial and physiological processes occur during forage harvest and storage and are almost always deleterious. These processes are influenced by preharvest factors such as mowing time of day, plant species, and maturity stage, as well as by harvest and storage variables. Avoidance o...
Recreational diving is a popular sport, although human ability to stay in and under water is severely limited physiologically. An understanding of these limitations enhances safety and enjoyment of sports diving. Breath-hold diving involves head-out water immersion, apnoea and submersion, exercise, cold stress, and pressure exposure. Each of these components, by itself, elicits prominent and specific physiological effects. Combination of these factors produces a unique and interesting physiological response generally known as diving reflex. Humans display weak diving responses, but exhibit no oxygen conservation function. Nevertheless, application of diving-induced physiological changes is now finding its way into clinical practice. Apnoea, face immersion, and head-out water immersion all show promise of clinical application. There are several spin-offs from diving research worth noting. Diuresis, enhancement of cardiac performance, and redistribution of blood flow, all produced by head-out water immersion, have been shown to be clinically useful, besides providing physiological data useful to space travel. Results from investigations on apnoea have been shown to be relevant to the following: treating some forms of cardiac arrhythmias; understanding drowning, sudden infant death syndrome and sleep apnoea; and confirming hyperventilation as the major cause of drowning. In comparison to marine mammals, humans are poor divers because of severe physiological constraints which limit their breath-hold time, diving depth, and ability to conserve body heat. Although under special circumstances humans can achieve unusually long breath-hold time and reach exceptional depth with a single breath, the sustainable working time and depth are only about 1 minute and 5 metres, respectively. Hypothermia inevitably results in divers working in the ocean. Without thermal protection, the intolerable limit of 35 degrees C is reached within 30 minutes in winter (10 degrees C) water and within 60 to 90 minutes in summer. Nevertheless, effective harvest work can be performed by humans in the ocean, and recreational benefits enhanced when these physiological limitations are respected. An unusual circulatory state exists during head-out water immersion in that there is a sustained increase of stroke volume. This results in 30% increase in cardiac output when the subject is resting in thermal neutral water, indicating a substantial overperfusion for the oxygen requirement. Furthermore, animal experiments showed that the elevated blood flow is preferentially channeled to the liver, fat, and the organs in the splanchnic region.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:3278355
Lin, Y C
Establishment and maintenance of pregnancy is difficult in lactating dairy cows exposed to heat stress because of reductions in estrous detection rate and the proportion of inseminated cows that maintain pregnancy. The most common approach to ameliorate heat stress in developed countries has been to alter the cow's environment through provision of shade, fans, sprinklers, and so on. Nonetheless, seasonal variation in reproductive function persists. Increased understanding of bovine reproductive function and its alteration by heat stress has led to additional strategies for reducing deleterious consequences of heat stress on reproduction. These include hormonally induced timed artificial insemination, which can reduce losses in reproductive efficiency caused by poor detection of estrus, and embryo transfer, which can increase pregnancy rate by allowing embryos to bypass the period when they are most sensitive to elevated temperature (i.e., in the first 1 to 2 d after breeding). Other efforts are directed toward developing methods to protect the embryo from harmful actions of elevated temperature. Approaches being studied include manipulation of embryonic synthesis of heat shock proteins and use of antioxidants to reduce free radical damage associated with heat stress. It may also be possible to reduce the magnitude of hyperthermia caused by heat stress. This might be possible physiologically, for example by feeding of agents that affect thermoregulatory systems, or genetically by selecting for specific traits conferring thermal resistance. Finally, the development of bovine somatotropin as a lactational promotant means that it may be possible to extend lactations beyond 305 d and voluntarily discontinue inseminations during periods of heat stress. PMID:15526779
Hansen, P J; Aréchiga, C F
Charles Darwin dedicated more than 20 years of his life to a variety of investigations on higher plants (angiosperms). It has been implicitly assumed that these studies in the fields of descriptive botany and experimental plant physiology were carried out to corroborate his principle of descent with modification. However, Darwins son Francis, who was a professional plant biologist, pointed out that the interests of his father were both of a physiological and an evolutionary nature. In this article, we describe Darwins work on the physiology of higher plants from a modern perspective, with reference to the following topics: circumnutations, tropisms and the endogenous oscillator model; the evolutionary patterns of auxin action; the root-brain hypothesis; phloem structure and photosynthesis research; endosymbioses and growth-promoting bacteria; photomorphogenesis and phenotypic plasticity; basal metabolic rate, the Pfeffer-Kleiber relationship and metabolic optimality theory with respect to adaptive evolution; and developmental constraints versus functional equivalence in relationship to directional natural selection. Based on a review of these various fields of inquiry, we deduce the existence of a Darwinian (evolutionary) approach to plant physiology and define this emerging scientific discipline as the experimental study and theoretical analysis of the functions of green, sessile organisms from a phylogenetic perspective.
Kutschera, Ulrich; Niklas, Karl J.
The protective effect of bovine somatotropin (bST) during experimental Streptococcus uberis mastitis in cows was studied. The left quarters of 10 cows were infected with 500 cfu of S. uberis O140J. Five cows were subcutaneously treated with 500 mg of recom- binant bST 7 d before and after infection, and 5 control cows received the excipient. In the treated cows,
D. Hoeben; C. Burvenich; P. J. Eppard; D. L. Hard
The use of prepubertal females (calves) to obtain oocytes for in vitro fertilization (IVF) programs, is being analyzed currently. This will increase the availability of female oocytes and will allow a reduction of the interval between generations. Differentials in the development capability of calf and cow oocytes have been assessed by different authors, establishing several ultrastructural and metabolic differences between them. This paper analyzes the morphometric and cytochemical differences between calf and cow oocytes through microscopic techniques. The oocytes morphologically classified as good are processed for electron microscopy a) in Epon 812 epoxy resin for morphometric analysis or b) in low temperature Lowycril K4M resin for cytochemical evaluation using Con A, GS, LPA, UEA, and WGA lectins marked with colloidal gold as probes. Calf oocytes show a greater density of microvilli on their surface and a greater number of endocytosic vesicles than those of the cow. On the other hand, cow oocytes show a larger superior mitochondrial population. In the cumulus cells it can be seen that calf oocytes have a greater volume of lipid droplets. Cytochemical analysis shows that calf oocytes have lectin marking restricted to the plasmic membrane, highlighting the presence of LPA. In cow oocytes, lectin marking can be seen both on the plasmic membrane and in the vacuoles, in both cases, with the LPA highlighted. In the zona pellucida of calf and cow oocytes, the same sugars appear (GS, LPA, WGA), and marking with LPA is more extensive in cow oocytes. PMID:11322238
de Paz, P; Sánchez, A J; De la Fuente, J; Chamorro, C A; Alvarez, M; Anel, E; Anel, L
To assess the effects of continuous exercise training at intensities corresponding to 80 and 90 % of the lactate minimum test (LM), we evaluated antioxidant activity, hormone concentration, biochemical analyses and aerobic and anaerobic performance, as well as glycogen stores, during 12 weeks of swimming training in rats. One-hundred rats were separated into three groups: control (CG, n = 40), exercise at 80 (EG80, n = 30) and 90% (EG90, n = 30) of LM. The training lasted 12 weeks, with sessions of 60 min/day, 6 days/week. The intensity was based at 80 and 90% of the LM. The volume did not differ between training groups (X of EG80 = 52 ± 4 min; X of EG90 = 56 ± 2 min). The glycogen concentration (mg/100 mg) in the gastrocnemius increased after the training in EG80 (0.788 ± 0.118) and EG90 (0.795 ± 0.157) in comparison to the control (0.390 ± 0.132). The glycogen stores in the soleus enhanced after the training in EG90 (0.677 ± 0.230) in comparison to the control (0.343 ± 0.142). The aerobic performance increased by 43 and 34% for EG80 and EG90, respectively, in relation to baseline. The antioxidant enzymes remain unchanged during the training. Creatine kinase (U/L) increased after 8 weeks in both groups (EG80 = 427.2 ± 97.4; EG90 = 641.1 ± 90.2) in relation to the control (246.9 ± 66.8), and corticosterone (ng/mL) increased after 12 weeks in EG90 (539 ± 54) in comparison to the control (362 ± 44). The continuous exercise at 80 and 90% of the LM has a marked aerobic impact on endurance performance without significantly biomarkers changes compared to control. PMID:23456272
de Araujo, Gustavo Gomes; Papoti, Marcelo; Delbin, Maria Andréia; Zanesco, Angelina; Gobatto, Claudio Alexandre
This summer workshop successfully exposed beginning graduate students, research technicians from industry, and other scientists to modern concepts and experimental protocols in an area that both DOE and NSF perceived to be lacking in U.S. science. 70 students participated in this workshop over 5 summers. Each summer, 12-16 students spent 2-4 weeks at The Ohio State University covering four distinct modules through lectures, laboratory sessions, and interaction with internationally recognized eminent scientists.
Tabita, F. R.
Abstract Metabolic responses to physical activities in subjects on normal diets are well known, but only a few,studies have assessed the effects of dietary conditions on endurance,performance,during a ritual fasting such as Ramadan. We undertook the present study to gain more,information into alterations in physiologicalparameters,induced by a short-term fasting. Young and healthy athletes performed high intensity exercise, lasting for one
L Guéye; D Seck; A Samb; F Cissé; K Camara; Martineaud J. p
The drought stress tolerance of two Solanum tuberosum subsp. andigena landraces, one hybrid (adg×tbr) and Atlantic (S. tuberosum subsp. tuberosum) has been evaluated. Photosynthesis in the Andigena landraces during prolonged drought was maintained significantly longer than in the Tuberosum (Atlantic) line. Among the Andigena landraces, Sullu (SUL) was more drought resistant than Negra Ojosa (NOJ). Microarray analysis and metabolite data from leaf samples taken at the point of maximum stress suggested higher mitochondrial metabolic activity in SUL than in NOJ. A greater induction of chloroplast-localized antioxidant and chaperone genes in SUL compared with NOJ was evident. ABA-responsive TFs were more induced in NOJ compared with SUL, including WRKY1, mediating a response in SA signalling that may give rise to increased ROS. NOJ may be experiencing higher ROS levels than SUL. Metabolite profiles of NOJ were characterized by compounds indicative of stress, for example, proline, trehalose, and GABA, which accumulated to a higher degree than in SUL. The differences between the Andigena lines were not explained by protective roles of compatible solutes; hexoses and complex sugars were similar in both landraces. Instead, lower levels of ROS accumulation, greater mitochondrial activity and active chloroplast defences contributed to a lower stress load in SUL than in NOJ during drought.
Vasquez-Robinet, Cecilia; Mane, Shrinivasrao P.; Ulanov, Alexander V.; Watkinson, Jonathan I.; Stromberg, Verlyn K.; De Koeyer, David; Schafleitner, Roland; Willmot, David B.; Bonierbale, Merideth; Bohnert, Hans J.; Grene, Ruth
\\u000a Nostoc species establish nitrogen-fixing symbiotic associations\\u000a with representatives of the four main lineages of terrestrial plants: bryophyte hornworts and liverworts,\\u000a the pteridophyte fern Azolla, gymnosperm cycads, and the angiosperm genus\\u000a Gunnera. However, the plant partners represent only narrowly selected\\u000a groups within these lineages. The plant partner benefits by the acquisition of fixed nitrogen, but the\\u000a benefits to the Nostoc partner
John C. Meeks
The ozone layer acts like a giant sunshade, protecting forests and other life forms on the Earth's surface from much of the Sun's harmful ultraviolet radiation. The depletion in stratospheric ozone layer due to anthropogenically released pollutants such as CFCs during the last few decades has resulted in increased UV radiation at ground level. UV radiation (100-400 nm) consists of
S. S. SINGH; PANKAJ KUMAR; ASHWANI K. RAI
In biology, noise implies error and disorder and is therefore something which organisms may seek to minimize and mitigate against. We argue that such noise can be adaptive. Recent studies have shown that gene expression can be noisy, noise can be genetically controlled, genes and gene networks vary in how noisy they are and noise generates phenotypic differences among genetically identical cells. Such phenotypic differences can have fitness benefits, suggesting that evolution can shape noise and that noise may be adaptive. For example, gene networks can generate bistable states resulting in phenotypic diversity and switching among individual cells of a genotype, which may be a bet hedging strategy. Here, we review the sources of noise in gene expression, the extent to which noise in biological systems may be adaptive and suggest that applying evolutionary rigour to the study of noise is necessary to fully understand organismal phenotypes.
Viney, Mark; Reece, Sarah E.
Milk fever in dairy cows can be prevented by activating Ca homeostasis before calving. Homeostatic adaptation can be achieved by reducing dietary Ca availability. Formaldehyde-treated rice bran was studied to supply rumen protected phytic acid to reduce Ca availability. Twelve multiparous dry cows were used in a 3×3 Latin square change-over design with 5-day periods to test three dietary treatments. Diets consisted of a forage mix (maize silage, grass silage and hay), being 77% of ration dry matter, supplemented with three concentrates: Control (no formaldehyde-treated rice bran), T1 (100% formaldehyde-treated rice bran) and T2 (99.5% formaldehyde-treated rice bran with 0.6% Ca carbonate, to equal Ca content of Control). Dietary treatments did not affect urine pH (8.14, 8.13 and 8.11 for Control, T1 and T2 respectively) or dry matter intake (13.9, 13.7 and 13.8 kg for Control, T1 and T2 respectively). Including formaldehyde-treated rice bran in the diet resulted in lower urinary Ca/creatinine ratio (0.970, 0.457 and 0.618 for Control, T1 and T2 respectively). A sudden increase of urinary Ca excretion took place after withdrawal of T1 and T2 at introduction of Cont