Heat Stress: A Serious Disruptor of the Reproductive Physiology of Dairy Cows

Animals, Journal Year: 2023, Volume and Issue: 13(11), P. 1846 - 1846

Published: June 1, 2023

Global warming is a significant threat to the sustainability and profitability of dairy sector, not only in tropical or subtropical regions but also temperate zones where extreme summer temperatures have become new challenging reality. Prolonged exposure cows high compromises animal welfare, increases morbidity, suppresses fertility, resulting devastating economic losses for farmers. To counteract deleterious effects heat stress, cattl e employ various adaptive thermoregulatory mechanisms including molecular, endocrine, physiological, behavioral responses. These adaptations involve immediate secretion shock proteins cortisol, followed by complex network disrupted metabolic reproductive hormones such as prolactin, ghrelin, ovarian steroid, pituitary gonadotrophins. While strategic stress mitigation measures can restore milk production through modifications microclimate nutritional interventions, fertility records remain at low levels compared those thermoneutral periods year. This because sustainment multifaceted process that requires appropriate energy balance, undisrupted mode sustain maturation fertilizing competence oocyte, normal development early embryo unhampered maternal—embryo crosstalk. In this review, we summarize major molecular endocrine responses elevated cows, well impacts on maturing oocytes embryos, discuss consequences brings about cattle fertility.

Language: Английский

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Invited review: From heat stress to disease—Immune response and candidate genes involved in cattle thermotolerance

Journal of Dairy Science, Journal Year: 2023, Volume and Issue: 106(7), P. 4471 - 4488

Published: May 8, 2023

Heat stress implies unfavorable effects on primary and functional traits in dairy cattle and, consequence, the profitability of whole production system. The increasing number days with extreme hot temperatures suggests that it is imperative to detect heat status animals based adequate measures. However, confirming an individual still challenging, identification novel biomarkers, including molecular remains a very relevant issue. Currently, known seems have immune system mechanisms, but this information limited use context phenotyping. In addition, there lack knowledge addressing mechanisms linking genes observed phenotype. review, we explored potential explaining how affects therefore, increases occurrence immune-related diseases cattle. regard, 2 relatively opposite hypotheses are under focus: immunosuppressive action cortisol, proinflammatory effect stress. both hypotheses, modulation response during highlighted. Moreover, possible link candidate these mechanisms. context, markers valuable indicators for detection cattle, broadening portfolio biomarkers

Language: Английский

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Climate change and pregnancy complications: From hormones to the immune response

Frontiers in Endocrinology, Journal Year: 2023, Volume and Issue: 14

Published: April 5, 2023

Pregnant women are highly vulnerable to adverse environments. Accumulating evidence highlights that increasing temperatures associated with the ongoing climate change pose a threat successful reproduction. Heat stress caused by an increased ambient temperature can result in pregnancy outcomes, e.g. , preterm birth, stillbirth and low fetal weight. The pathomechanisms through which heat interferes maintenance still remain vague, but emerging underscores endocrine system is severely affected. It well known pivotally contributes physiological progression of pregnancy. We review – sometimes speculate - how offset hormonal dysregulations subsequently derail other systems interact hormones, such as immune response. This may account for heat-stress related progression, development long-term children’s health.

Language: Английский

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Investigating the Potential of Geothermal Heat Pump and Precision Air Supply System for Heat Stress Abatement in Dairy Cattle Barns

Journal of Thermal Biology, Journal Year: 2025, Volume and Issue: 127, P. 104039 - 104039

Published: Jan. 1, 2025

Language: Английский

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Acute and chronic impacts of heat stress on planetary health

Allergy, Journal Year: 2023, Volume and Issue: 78(8), P. 2109 - 2120

Published: March 8, 2023

Abstract Heat waves are increasing in intensity, frequency, and duration causing significant heat stress all living organisms. has multiple negative effects on plants affecting photosynthesis, respiration, growth, development, reproduction. It also impacts animals leading to physiological behavioral alterations, such as reduced caloric intake, increased water decreased reproduction growth. In humans, epidemiological studies have shown that associated with morbidity mortality. There many biological of (structural changes, enzyme function disruption, damage through reactive oxygen or nitrogen species). While can mitigate some these adaptive mechanisms the generation shock proteins, antioxidants, granules, others, may likely be inadequate further global warming. This review summarizes adaptative evolved counteract this stress.

Language: Английский

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Effects of Heat Stress in Dairy Cows Raised in the Confined System: A Scientometric Review

Animals, Journal Year: 2023, Volume and Issue: 13(3), P. 350 - 350

Published: Jan. 19, 2023

Due to climate change, heat stress is a growing problem for the dairy industry. Based on this, annual economic losses in sector are verified mainly large scale. Despite several publications thermal lactating cows confinement systems, there need be published reviews addressing this issue systematically. Our objective was scientometrically analyze effects of managed system. PRISMA guidelines, research articles were identified, screened, and summarized based inclusion criteria Data obtained from Web Science. A total 604 scientific between 2000 April 2022 considered. then analyzed using Microsoft Excel CiteSpace. The results pointed significant increase studies housed systems. main areas Agriculture, Dairy Animal Science Veterinary Sciences. USA showed highest concentration (31.12%), followed by China (14.90%). Emerging themes included behavior. most influential journals Journal top authors L. H. Baumgard R. J. Collier. leading institutions Chinese Academy Agricultural Sciences, State University System Florida Florida. study maps domains discusses implications explanations highlights emerging trends.

Language: Английский

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Chronic exposure to warm temperature causes low sperm abundance and quality in Drosophila melanogaster

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: July 30, 2023

Abstract Temperature influences male fertility across organisms; however, how suboptimal temperatures affect adult spermatogenesis remains understudied. In a recent study on Drosophila melanogaster oogenesis, we observed drastic reduction in the of males exposed to warm temperature (29 °C). Here, show that become infertile at 29 °C because low sperm abundance and quality. The does not stem from reduced germline cell or spermatid numbers, as those numbers remain comparable between control 25 °C. Notably, cold 18 had similarly increased frequencies elongation individualization defects which, considering high measured °C, indicate has tolerance for defects. Interestingly, decreases abruptly with no evidence apoptosis they transition into seminal vesicle near end spermatogenesis, pointing elimination through an unknown mechanism. Finally, fertilize eggs less efficiently do support embryos past first stage embryogenesis, indicating poor quality is additional cause infertility

Language: Английский

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Subchronic elevation in ambient temperature drives alterations to the sperm epigenome and accelerates early embryonic development in mice

Proceedings of the National Academy of Sciences, Journal Year: 2024, Volume and Issue: 121(47)

Published: Nov. 11, 2024

Forecasted increases in the prevalence and severity of extreme weather events accompanying changes climatic behavior pose potential risk to reproductive capacity humans animals ecological agricultural significance. While several studies have revealed that heat stress induced by challenges such as testicular insulation can elicit a marked negative effect on male system, particularly production spermatozoa, less is known about immediate impact function following subchronic whole-body exposure elevated ambient temperature. To address this knowledge gap, we exposed unrestrained mice conditions emulate wave (daily cycle 8 h at 35 °C followed 16 25 °C) for period 7 d. Neither testes or epididymides heat-exposed exhibited evidence gross histological change, similarly, spermatozoa males retained their functionality ability support embryonic development. However, embryos generated from experienced pronounced gene expression linked acceleration early embryo development, aberrant blastocyst hatching, increased fetal:placental weight ratio. Such were causally associated with an altered sperm small noncoding RNA (sncRNA) profile, these developmental phenotypes recapitulated microinjection wild-type sired control RNAs extracted spermatozoa. data highlight even relatively modest excursions temperature affect identify sncRNA profile particular point vulnerability imposed environmental stress.

Language: Английский

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Warm and cold temperatures have distinct germline stem cell lineage effects during Drosophila oogenesis

Development, Journal Year: 2022, Volume and Issue: 149(5)

Published: Feb. 14, 2022

Despite their medical and economic relevance, it remains largely unknown how suboptimal temperatures affect adult insect reproduction. Here, we report an in-depth analysis of chronic exposure to affects oogenesis using the model Drosophila melanogaster. In females maintained at 18°C (cold) or 29°C (warm), relative 25°C control temperature, egg production was reduced through distinct cellular mechanisms. Chronic improved germline stem cell maintenance, survival early cysts oocyte quality, but follicle growth with no obvious effect on vitellogenesis. By contrast, in 29°C, numbers were similar those 25°C, while cyst death degeneration vitellogenic follicles markedly increased quality plummeted over time. Finally, also show that these effects are independent diet, male factors canonical temperature sensors. These findings relevant not only cold-blooded organisms, which have limited thermoregulation, potentially warm-blooded susceptible hypothermia, heatstroke fever.

Language: Английский

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Characterization of Thermal Patterns Using Infrared Thermography and Thermolytic Responses of Cattle Reared in Three Different Systems during the Transition Period in the Eastern Amazon, Brazil

Animals, Journal Year: 2023, Volume and Issue: 13(17), P. 2735 - 2735

Published: Aug. 28, 2023

In the Lower Amazon mesoregion, there are basically three types of production systems: traditional (without shade and no bathing area), silvopastoral (with integrated area). It is considered that type system influences thermal comfort productivity cattle, so this research aims to evaluate influence these systems on thermoregulation Nellore cattle. The experiment was carried out a rural property for raising located in Mojuí dos Campos, Pará, Brazil, during transition period (June/July). Thirty bovine males (not castrated, aged between 18 20 months, average weight 250 ± 36 kg, body condition score 3.5, clinically healthy) were randomly divided into groups: Silvopastoral System-SS (n = 10), Traditional System-TS Integrated System-IS 10). Climate variables collected (air temperature (AT °C), relative humidity (RH %), wind speed (WS, m/s), solar radiation (SR), black globe (BGT physiological parameters, such as respiratory rate (RR) rectal (RT)) at 6 a.m., 12 p.m., a.m. determine situation animals. Thermographic images environment animals captured order obtain surface (BST) through infrared thermography. Benezra Thermal Comfort Index (BTCI), Environmental Stress (ESI), Equivalent Temperature (ETI), Iberian Heat Tolerance (Iberian HTI) used. results showed system, with shading by chestnut trees an ample vegetative area, presented better conditions, 28.98 °C, comparison (35.93 °C) one (34.11 °C). observed cattle did not differ significantly anatomical regions studied (p > 0.05). As rate, registered higher values, 41 movements per minute, indicating possible stress < indices revealed all moderate conditions times intensity. concluded proved be more favorable providing reducing stress, which may have positive impact animal welfare region.

Language: Английский

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