The Impact of Heat Load on Cattle

Animals, Journal Year: 2019, Volume and Issue: 9(6), P. 322 - 322

Published: June 6, 2019

Heat stress and cold have a negative influence on cattle welfare productivity. There been some studies investigating the of cattle, however emphasis within this review is heat cattle. The impact hot weather increasing importance due to changing global environment. worldwide phenomenon that associated with reduced animal productivity welfare, particularly during summer months. Animal responses their thermal environment are extremely varied, however, it clear influences health, productivity, Whilst knowledge continues be developed, managing livestock reduce climatic conditions remains somewhat challenging. This provides an overview production reproduction in bovines.

Language: Английский

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Heat Stress Impacts Immune Status in Cows Across the Life Cycle

Frontiers in Veterinary Science, Journal Year: 2020, Volume and Issue: 7

Published: March 6, 2020

Heat stress has a myriad of effects on dairy cattle across the life cycle. Whereas, most commonly recognized impacts are associated with production responses, emerging evidence indicates that heat profoundly alters immune response calves and cows, from prenatal stage through lactation. For example, in utero reduces passive transfer regardless colostrum source, relative to normothermic conditions late gestation. Dry cows exposed have lower immunoglobulin responses ovalbumin vaccination, but this effect dissipates cooling following parturition. Conversely, under when dry exhibit carryover innate arm system early In paper we review throughout cycle cow, particular emphasis impact during gestation cow developing fetus, both before after addition, altered status other physiological systems, especially those supporting milk production, considered. Finally, management interventions prevent reverse presented.

Language: Английский

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Late-gestation heat stress impairs daughter and granddaughter lifetime performance

Journal of Dairy Science, Journal Year: 2020, Volume and Issue: 103(8), P. 7555 - 7568

Published: June 10, 2020

Records of late-gestation heat stress studies conducted over 10 consecutive years in Florida were pooled and analyzed to test the hypothesis that maternal hyperthermia during late gestation impairs performance offspring across multiple generations lactations, ultimately impeding profitability US dairy sector. Dry-pregnant multiparous dams actively cooled (CL; shade a freestall barn, fans water soakers, n = 196) or not (HT; only, 198) last 46 d gestation, concurrent with entire dry period. After data mining, records 156 daughters (F1) born either CL (CLF1, 77) HT (HTF1, 79) 45 granddaughters (F2) CLF1 (CLF2, 24) HTF1 (HTF2, 21) used analysis. Life events daily milk yield for 3 lactations obtained. Milk yield, reproductive performance, productive life using MIXED GLIMMIX procedures, lifespan was PHREG LIFETEST procedures SAS (SAS Institute Inc., Cary, NC). production reduced their first (2.2 kg/d), second (2.3 third (6.5 kg/d) compared CLF1. More culled before calving, relative (4.9 11.7 mo, respectively). The (HTF2) produced less lactation (1.3 (CLF2) HTF2 breeding CLF2; however, different between CLF2 animals. An economic analysis then performed based on number days, cows per state, aforementioned impairments daughters' lifespans production. Collectively United States, losses additional heifer rearing cost, life, F1 estimated at $134, $90, $371 million year, respectively. In summary, exerts carryover effects least 2 generations. Providing abatement dry-pregnant is important rescue loss dam prevent progeny.

Language: Английский

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Reproductive physiology of the heat-stressed dairy cow: implications for fertility and assisted reproduction

Animal Reproduction, Journal Year: 2019, Volume and Issue: 16(3), P. 497 - 507

Published: Jan. 1, 2019

Heat stress causes a large decline in pregnancy success per insemination during warm times of the year. Improvements fertility are possible by exploiting knowledge about how heat affects reproductive process. The oocyte can be damaged at earliest stages folliculogenesis and remains sensitive to peri-ovulatory period. Changes quality due result altered patterns and, possibly, direct effects elevated body temperature on oocyte. While adverse have been observed vitro, local cooling ovary protective follicular fluid may limit these actions vivo. also compromise fertilization rate. first seven days embryonic development very susceptible disruption stress. During days, embryo undergoes rapid change sensitivity from being (2- 4-cell stage) largely resistant (by morulae stage). Direct likely an important mechanism for reduction survival caused An effective way avoid oocyte, fertilization, early is bypass through transfer because embryos typically transferred into females after acquisition thermal resistance. There some opportunity mitigate feeding antioxidants or regulating endocrine environment cow but neither approach has reduced practice. best long-term solution problem increase genetic resistance cows Thermotolerance genes exist within dairy breeds additional introgressed other traditional means gene editing.

Language: Английский

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Symposium review: One-carbon metabolism and methyl donor nutrition in the dairy cow

Journal of Dairy Science, Journal Year: 2020, Volume and Issue: 103(6), P. 5668 - 5683

Published: April 9, 2020

The present review focuses on methyl donor metabolism and nutrition in the periparturient lactating dairy cow. Methyl donors are involved one-carbon metabolism, which includes folate Met cycles. These cycles work unison to support lipid, nucleotide, protein synthesis, as well methylation reactions maintenance of redox status. A key feature is multi-step conversion tetrahydrofolate 5-methyltetrahyrofolate. Homocysteine 5-methyltetrahyrofolate utilized by vitamin B12-dependent synthase couple generate Met. Methionine may also be remethylated from choline-derived betaine under action hydroxymethyltransferase. Regardless, converted within cycle S-adenosylmethionine, universally methyl-group transfer including synthesis phosphatidylcholine. enter transsulfuration pathway glutathione or taurine for scavenging reactive oxygen metabolites. In transition cow, a high demand exists compounds with labile group. Limited group supply contribute inadequate hepatic phosphatidylcholine triglyceride export, systemic oxidative stress, compromised milk production. To minimize perils associated deficiency, peripartum cow relies de novo methylneogenesis tetrahydrofolate. addition, dietary supplementation rumen-protected folic acid, B12, Met, choline, potential nutritional approaches target pools improve balance cows. Such strategies have merit considering research demonstrating their ability production efficiency, health, immune response. This aims summarize current understanding utilization co-supplementation, fatty acid feeding that optimize efficacy, epigenetic mechanisms considered.

Language: Английский

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Impacts of Epigenetic Processes on the Health and Productivity of Livestock

Frontiers in Genetics, Journal Year: 2021, Volume and Issue: 11

Published: Feb. 23, 2021

The dynamic changes in the epigenome resulting from intricate interactions of genetic and environmental factors play crucial roles individual growth development. Numerous studies plants, rodents, humans have provided evidence regulatory epigenetic processes health disease. There is increasing pressure to increase livestock production light food needs an expanding human population environment challenges, but there limited related data on complement genomic information support advances improvement breeding management. This review examines recent discoveries due DNA methylation, histone modification, chromatin remodeling their impacts traits farm animals, including bovine, swine, sheep, goat, poultry species. Most reports focused profiling at genome-wide or specific genic regions response developmental processes, stressors, nutrition, disease pathogens. bulk available mainly characterized markers tissues/organs relation detection mechanisms underlying phenotype diversity. However, inadequate gainful exploitation for improved animal productivity Increased research effort, which vital elucidate how affect livestock, currently several lack adequate analytical tools. In this review, we (1) summarize traits, (2) discuss application epigenetics production, (3) present gaps research. Knowledge influencing management productivity.

Language: Английский

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Invited review: Management strategies capable of improving the reproductive performance of heat-stressed dairy cattle

Journal of Dairy Science, Journal Year: 2019, Volume and Issue: 102(12), P. 10695 - 10710

Published: Sept. 11, 2019

Language: Английский

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Late gestation heat stress in dairy cows: Effects on dam and daughter

Theriogenology, Journal Year: 2020, Volume and Issue: 150, P. 471 - 479

Published: March 19, 2020

Language: Английский

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Pre- and postnatal heat stress abatement affects dairy calf thermoregulation and performance

Journal of Dairy Science, Journal Year: 2020, Volume and Issue: 103(5), P. 4822 - 4837

Published: Feb. 26, 2020

Prenatal heat stress during late gestation exerts long-term effects on growth and productivity of the dairy calf. Further, direct exposure to preweaning period impairs calf thermoregulation performance. We examined abatement prenatal period, postnatal or both hypothesized that calves exposed pre- would perform most optimally in terms thermoregulation, growth, health responses when compared with are heat-stressed at any time periods. Holstein born (HT) cooled (CL) dams (44 ± 5 d; HT CL) were cooling postnatally for 56 d (postnatal CL), resulting 4 treatments: HT-HT, HT-CL, CL-HT, CL-CL; n = 12/treatment. Calves administered L pooled colostrum after 2 age allotted 10 L/d milk replacer up 3 kg/d concentrate automatic feeder group pens (n 6/pen). Postnatal was achieved by fans (average wind speed m/s). Thermoregulatory (respiration rate heart rate; rectal, body, skin temperature), feed intake, parameters including average daily gain medication events recorded, blood samples collected weekly. lower CL HT. In afternoon, HT-HT had highest respiration rectal temperature, HT-CL lowest rate, CL-HT other treatment groups. weighed more birth weaning a tendency greater calves, whereas increased intake reduced fever, infection, total relative esophageal tube fed often than CL. Blood hematocrit 24-h serum IgG concentration improves weight gain, hematocrit, immunoglobulin transfer, modulates thermoregulatory responses, health. This study is first characterize combined active

Language: Английский

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The Impact of Heat Stress on Immune Status of Dairy Cattle and Strategies to Ameliorate the Negative Effects

Animals, Journal Year: 2022, Volume and Issue: 13(1), P. 107 - 107

Published: Dec. 27, 2022

Heat stress (HS) is well known to influence animal health and livestock productivity negatively. a multi-billion-dollar global problem. It impairs performance during summer when animals are exposed high ambient temperatures, direct indirect solar radiations, humidity. While significant developments have been achieved over the last few decades mitigate negative impact of HS, such as physical modification environment protect from heat, HS remains challenge for dairy industry compromising cattle welfare. In scenario, it essential thorough understanding how immune system responds identify variable responses among animals. This could help heat-resilient breeding may lead development climate resilient breeds in future support sustainable production. There sufficient data demonstrating increased temperature humidity on endocrine cattle, especially changes concentration hormones like prolactin cortisol, which also provide an indication likely im-pact system. this paper, we review recent research immunity calves early life adult lactating dry cows. Additionally, different strategies amelioration effects presented.

Language: Английский

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