Heat Stress and Goat Welfare: Adaptation and Production Considerations

Climate resilience in goats: a comprehensive review of the genetic basis for adaptation to varied climatic conditions

The sustainability of livestock systems is widely acknowledged to be threatened by climate change on a worldwide scale. There are worries about the effects this phenomenon may have on the productivity and performance of native livestock species due to its influence on environmental stresses, such as the frequency and severity of unfavorable weather occurrences and the ongoing changes in the agro-ecological landscape. Among the most climatically tolerant livestock animals, goats can survive in a range of environments, from deserts to alpine areas. The domestic goat has undergone significant phenotypic changes in terms of shape, behavior, physiological adaptation, reproduction, and production over their evolutionary journey. It will be possible to better understand the genetic mechanisms underlying successful domestication and the practical breeding strategies leading to the improvement in productivity and resilience to environmental challenges by identifying the genes underlying these modifications. This review explores current knowledge on goat adaptation strategies, emphasizing gene expression patterns, epigenetic modifications, and whole-genome selection signatures. It examines how these molecular mechanisms enable goats to endure heat stress, hypoxia, and other environmental challenges. Furthermore, the review highlights the potential of epigenetic markers and selection signatures in developing climate-resilient goat breeds through marker-assisted selection and genome editing, offering actionable insights into sustainable goat production in the context of global climate change.

Proposing a strategy based on body-thermal status to improve the welfare of heat-stressed and water-deprived goats (Capra hircus)

OBJECTIVE

Despite the considerable body of research on the effects of heat stress coupled with water scarcity (either through restriction or deprivation) on goats, aimed at enhancing their welfare, there remains a notable gap in the literature regarding the subsequent period following water restoration, during which the cumulative impact is fully alleviated. In response to this gap, we propose a strategy grounded in the assessment of body-thermal status to improve the welfare of heat-stressed and water-deprived goats. Specifically, our strategy seeks to determine the minimally required recovery interval necessary to completely mitigate the residual effects of water deprivation endured for a duration of 72 hours.

METHODS

Eight healthy Aardi bucks, aged 10 months and weighing 30 kg, were subjected to three distinct stages: euhydration, dehydration, and rehydration. Each stage spanned for 72 hours except for the rehydration stage, which was left unrestricted. Various meteorological, biophysiological, and thermophysiological measurements were subsequently recorded.

RESULTS

Exposure of heat-stressed goats, as indicated by the temperature-humidity index values, to a 72 hours deprivation period resulted in noticeable (p<0.05) alterations in their biophysiological (daily feed intake, body weight, and feces water content) and thermophysiological responses (core, rectal, skin, and surface temperatures, respiratory and heart rates, internal, external, and total body-thermal gradients, heat tolerance and adaptability coefficients, heterothermial total body-heat storage, and total water conservation). Remarkably, our findings demonstrate that all assessed variables, whether measured or estimated, returned to their baseline euhydration levels within 10 days of commencing the rehydration phase.

CONCLUSION

In order to improve the welfare of heat-stressed and 72 hours water-deprived goats, it is imperative to allow a recovery period of no less than 10 days following the restoration of water access prior to initiating any subsequent experiments involving these animals. Such experiments, addressing these critical aspects, serve to advance our understanding of goat welfare and obviously hold promise for contributing to future food security and economic viability.

Behavioral, physiological, and hormonal responses during pre-slaughter handling in goats: a comparison between trained and untrained handlers

OBJECTIVE

The livestock handler attitude and their handling of animals is crucial for improving animal welfare standards, minimizing stress, improving productivity and meat quality. The present study was undertaken to assess the effect of training livestock handlers on behavioral, physiological, and hormonal responses during preslaughter handling in goats.

METHODS

A total of 6 handlers were divided into trained (trained in basic animal handling practices, animal behavior, and animal welfare), contact trained (not trained directly but interacted and saw the working of trained handlers), and untrained groups (no formal training). The handling experiment was conducted on 18 male goats by following a crossover design. The goats were moved from lairage to slaughter point by trained, contact-trained, and untrained handlers. Various behavioral, physiological, and hormonal parameters were recorded at the lairage before handling and at the slaughter point after handling the goats.

RESULTS

The training of livestock handlers had a significant effect on behavioral, physiological, and hormonal responses in goats. The goats handled by untrained and contacttrained handlers were recorded with intense vocalization, significant (p<0.05) increase in heart rate and blood glucose, and catecholamines (adrenaline and nor-adrenaline), thereby indicating stress and poor animal welfare. The trained handlers were observed to use visual interactions (waving of hands or objects, blocking, hand raising, etc), and lower stress responses were recorded in the goats handled by this group.

CONCLUSION

The present study highlights the importance of training to livestock handlers in improving animal welfare and minimizing stress in goats during pre-slaughter stress.

Bioactive compounds enrichment in rabbit doe's diet pre-and during pregnancy improves productive and reproductive performance and cost-effectiveness under hot climates

This study aimed to investigate the effect of diet supplementation with a symbiotic (SY), bee pollen (BP), honey bee (HB), date palm pollen (DPP) and their mixture (MIX) on female rabbit productive and reproductive performances under desert hot climates. Seventy-two Californian does of 5 months age and average body weight of 3250 ± 78.2 g were randomly allotted into six groups, each of 12 does. All does orally receive 3 ml distilled water for 10 days before mating and 28 days during pregnancy. Treatments were repeated for four consecutive parities. The first group served as control (C) given distilled water only, however the second, third, fourth and fifth groups were supplemented with 3 ml distilled water containing 0.2 ml SY, 200 mg DPP, 200 mg BP, 0.2 ml HB/doe per day, respectively. While, the sixth group does were given all previous ingredients (MIX). Sexual receptivity rate, fertility rate, kindling rate, and newborn traits were recorded. Also, maternal feed intake, feed conversion ratio, and digestibility coefficients of nutrients were recorded. Does in all groups were artificially inseminated with 0.5 ml of fresh heterospermic semen of 15 fertile bucks extended in Tris at 806-1006 sperm/ml. Treatment increased maternal body weight and daily gain with highest values (P < 0.05) in BP, SY, and MIX does. All treatments enhanced feed intake and feed conversion ratio (FCR) compared with control. Number services per conception decreased (P < 0.01), while litter size and weight and survival at birth and weaning increased (P < 0.01) in treated than control does. Treated does produced more milk than control. Digestibility coefficients of all nutrients were improved (P < 0.01) in treated does. In conclusion, supporting rabbit does pre- and during pregnancy with diets supplemented with a mixture of honey bee, date palm pollen, bee pollen, and synbiotic improves the productive and reproductive performances of rabbit does and their offspring.

Morphological adaptation to environmental stress in small ruminants from the sahelian zones of Niger and potential associations with carcass yield

This study analyses, in the Sahelian zone of Niger, the morphological traits of sheep and goats' responses to environmental stress and the contribution of adaptive traits to herd productivity. The study utilized 2490 adult small ruminants, including 653 red and Sahelian goats and 1837 Peulh (with three varieties: Balami, Oudah and Bali-Bali) and Tuareg (Ara-ara) sheep from 13 sites with a marked aridity gradient within the country's northern latitude. Carcass yield was assessed on a second sample of 1617 adult animals, comprising 876 sheep and 741 goats. Variations in thorax auricular index (ratio of ear length to thorax depth), gracility index (which reflects the subtraction of the animal's body from the ground) and hot carcass yield, according to climate zones and breed, were subjected to an analysis of variance at the 5% risk threshold. Principal Component Analysis was used to analyze correlations between biometric and heat indices. For most breeds, the auricular thorax index and the gracility index were higher for animals in arid zones than those in humid zones. The increase in the average values of the body indices had as a result an increase in the animals' carcass yield and live weight. In all sheep and goat breeds, gracility increases with heat index. Gracility differed (p < 0.05) between breeds, with Bali-Bali and Oudah subgenetics of the Peulh sheep breed being more gracile than the Ara-ara sheep. Also, the auricular thorax index was higher (p < 0.05) in Sahelian goat than in red goat. The importance of biometric indices in terms of animals' adaptability to their environment means that we need to define important heat stress indicators specific to sheep and goats in Sahelian farming systems.

Review: Update of nutritional requirements of goats for growth and pregnancy in hot environments

Goats play an important role in the agricultural business, providing valuable income sources through producing high-quality animal protein. They are widespread livestock for rural households due to their inherent resiliency, adaptability to many environments, and suitability in sustainable production systems. While goats are reared in highly diverse environments, a great portion of their population is reared in hot environments. Heat stress is known to affect goats' productive and reproductive performance negatively. However, goats can remarkably thrive in harsh conditions due to physiological, metabolic, and molecular adaptive mechanisms. In the face of it, in the last decades, the nutrition of goats, particularly their nutritional requirements, has received special attention. Research groups worldwide have dedicated their efforts to updating feeding systems for goats. Our objective was to present the recent findings on the energy and nutrient requirements of growing and pregnant goats in hot environments. Energy and protein requirements for the maintenance and growth of goats are influenced by sex and genotype only when mature weight is not considered in the models. Sex and genotype affect the efficiency of energy use for growth but do not affect the efficiency of protein use. Major mineral requirements for maintenance and growth are not affected by sex, except for magnesium. However, the phosphorus, sodium, and potassium requirements of goats raised in hot environments differ from those in the feeding systems. This difference may be related to the adaptation mechanisms goats employ to cope with the hot environmental conditions. Regarding requirements for pregnancy, there was no effect of days of pregnancy on the energy or protein requirements. The efficiency of metabolizable energy utilization for pregnancy increased with the progress of pregnancy. Mineral accretion for pregnancy differs between single and twin pregnancies and, irrespective of pregnancy type, the mineral requirements increase as pregnancy progresses. The differences between the estimated dietary requirements of goats raised in hot environments and the most widely adopted feeding systems suggest that these goats may be using energy and nutrients to cope with heat stress and other stressors associated with hot environments. The recent findings on energy, protein, and mineral requirements of growing and pregnant goats can be an important resource of information for enhancing feeding systems worldwide.

Feeding Behavior, Water Intake, and Physiological Parameters of Feedlot Lambs Fed with Diets Containing Babassu Oil Associated with Sunflower Oil Blend

This study aimed to investigate the impact of dietary inclusion of babassu oil (BO) associated with sunflower oil (SO) on feeding behavior, water intake, and physiological parameters of feedlot lambs. Thirty-five castrated male lambs (16.6 kg ± 3.9 kg) were distributed in a randomized block design with 5 treatments (diets) and 7 replications. The tested diets were oil-free diet (OF), 45 g/kg BO (BO), 30 g/kg BO with an additional 15 g/kg SO (1.5 SO), 22.5 g/kg BO with an additional 22.5 g/kg SO (2.25 SO), and 30 g/kg SO with an additional 15 g/kg BO (3.0 SO) on dry matter (DM) basis. The experimental period lasted 60 days. Animals that received BO diet and the combination of BO with SO had lower intakes of DM and neutral detergent fiber (NDF) compared to the control diet (P < 0.05). Differences on the respiratory rate (RR) was observed between animals in the control diet and those in the diets containing SO (P=0.001), with a linear increase in RR as the levels of SO in the diets increased (P=0.004). All physiological parameters showed a time effect (P < 0.05). Animals fed with the control diet had higher water intake via drinking fountain (P=0.030) and total water intake (P=0.029) compared to animals fed with diets containing SO. In relation to SO levels, water intake via drinking fountain (P=0.002), total water intake (P=0.002), and total water intake per kg of DM ingested (P=0.001) linearly increased with the levels increase in the composition of the diets. The tested diets did not alter the feeding behavior of the feedlot lambs. However, the combination of BO with different levels of SO reduced DM and water intake via drinking fountain and RR.

Seasonal assessment of mastitis in crossbred goats: A thermographic approach

Sub-clinical mastitis exhibits a higher prevalence in dairy goats than clinical mastitis, necessitating the adoption of non-invasive diagnostic techniques such as infrared thermography (IRT) to detect this economically significant production disease in the dairy sector. Accordingly, this study aims to employ IR imaging of the udder and teat quarters of lactating crossbred goats (Alpine × Beetal and Sanen × Beetal) across various seasons, utilising IRT, to discern cases of sub-clinical (SCM) and clinical mastitis (CM). Over a year, 100-110 lactating crossbred dairy goats underwent consistent IRT screenings, followed by a comprehensive evaluation of udder health status using the California mastitis test and somatic cell count (SCC). The receiver operating characteristic (ROC) analysis was conducted to establish the cut-off values for different thermographic parameters in this study. The results revealed that the SCC increased significantly (p < 0.01) in healthy, SCM, and CM milk samples across the seasons. The analysis of ROC revealed a comparatively higher sensitivity, specificity, and accuracy for udder thermograms during SCM than CM and vice versa for teat thermograms. IRT analysis reflected a difference (p < 0.01) in the udder and teat thermograms among quarters of healthy, SCM, and CM in summer, winter, autumn, and rainy seasons. A significant increase (p < 0.01) in udder thermograms was observed for quarters affected with SCM and CM relative to healthy, with an increase of 1.89 and 2.94 °C in winter, 0.85 and 1.63 °C in summer, 0.73 and 1.41 °C in rainy, and 1.33 and 2.38 °C in autumn, respectively. Similarly, for teat thermograms it was 1.79 and 2.81 °C in winter, 0.76 and 1.41 °C in summer, 0.70 and 1.37 °C in rainy, and 1.09 and 1.93 °C in autumn, respectively. Therefore, regardless of the seasons examined in this study, IRT proves to be an effective and supportive tool for early mastitis detection in lactating crossbred dairy goats.

The Effects of Dietary Pterostilbene on the Immune Response, Antioxidant Function, and Jejunal Structure of Broilers

This experiment was carried out to investigate the effect of pterostilbene (PTE) supplementation in feed on Arbor Acres broilers in terms of serum biochemical parameters, immune and inflammatory responses, antioxidant status, and intestinal morphological structure. For a duration of 42 days, a total of 480 1-day-old Arbor Acres broilers were randomly divided into four groups. Each group was assigned to receive either the basal diet or the basal diet supplemented with 200, 400, or 600 mg/kg of PTE. Each treatment consisted of eight replicates, with 15 chicks per replicate. In comparison with the control group, three PTE treatments significantly increased the lymphocyte transformation rate in the spleen of broilers. The automated biochemical analysis, enzyme-linked immunosorbent assay, and RT-qPCR analysis kits found that 400 mg/kg of PTE significantly increased the serum levels of complement C3, IL-4, and iNOS; reduced the serum levels of IL-6, TNF-α, and mRNA levels of the genes IL-6, IL-8, TNF-α, NLRP3, and IFN-γ; significantly improved the activities of antioxidant enzymes including CAT, GSH-Px, and T-SOD in the jejunum; and significantly reduced the MDA contents in the serum and jejunum of broilers. Nikon microscope observations and ImagePro Plus 6.0 measure results found that 400 mg/kg of PTE supplementation significantly reduced the relative length and weight of the jejunum and improved the jejunal villi structure, resulting in increased intestinal villi, deepened crypt, and an enhanced ratio of villi height to crypt depth (VH/CD). RT-qPCR and Western blot found that dietary PTE also resulted in increased mRNA levels of the genes Claudin-2, Occludin, ZO-1, and Sirt1, and decreased NF-κB protein levels in the jejunum. The results of this study demonstrated that dietary PTE improved the immune function and intestinal health of broilers by reducing inflammation and increasing the antioxidant capacity of the animals.

Investigating the impact of preslaughter handling intensity on goats: a study on behavior, physiology, blood enzymes, and hormonal responses

Introduction

The present study evaluated the effect of preslaughter stress intensities on the behavioral, physiological, blood biochemicals, and hormonal responses in goats.

Methods

Twenty-seven intact male goats (Ardi breed, 10 months of age, 27 kg liveweight) were divided into three treatment groups viz., the control (C) group, ear pulling (EP) group, and leg pulling (LP) group. Various behavioral, physiological, blood biochemical and hormonal responses were recorded before and after handling.

Results and Discussion

The EP and LP goats had a higher frequency and intensity of vocalization as compared to control goats. The preslaughter handling stress intensities had a significant effect on the before and after handling values of heart rate, respiration rate, rectal temperature, and ear temperature. Further, among groups, the glucose value increased significantly upon preslaughter handling as compared to the baseline value. The LP goats had significantly higher after-handling value for lactate dehydrogenase (LDH) as compared to the before-handling value. The catecholamines (adrenaline and noradrenaline) and β-endorphin concentrations increased significantly upon preslaughter handling. The higher physiological, behavioral, blood biochemical, and hormonal response indicated higher preslaughter stress in EP and LP goats. Both levels of intensity revealed unfavorable responses in goats that may adversely affect animal welfare and meat quality. Thus, to ensure minimal adverse effects on behavior, physiology, blood enzymes, and hormonal responses, it is recommended to follow animal welfare principles when implementing preslaughter handling practices.

Screening of InDel variants in PRDM6, myostatin and IGF2BP1 genes and association analysis with body measurement traits in Malabari and Attappadi black goats

An insertion/deletion (InDel) polymorphism study of PR/SET domain family 6 (PRDM6), myostatin (MSTN) and insulin-like growth factor 2 mRNA binding protein 1 (IGF2BP1) genes was conducted in Malabari and Attappady black goats. An association study of identified InDels and body measurement traits was also performed. Body measurements included body length, chest diameter, chest depth, canon circumference, hip width, and hip height at the hip cross. The body trunk index, the body length index, the canon circumference index, and the chest width index were calculated. The Hardy-Weinberg equilibrium (HWE) was tested using a Chi-square test. The observed heterozygosity (Ho), expected heterozygosity (He), and polymorphism information content (PIC) were calculated. A significant difference in body measurements was found across breeds, ages, and breed x age interactions. The PRDM6 InDel was also associated with body measurement traits, such as body height, canon circumference and canon circumference index. In both Malabari and Attappadi black MSTN and PRDM6 InDels were in a state of HWE, while IGF2BP1 InDels were not. Indel markers found in the present study may be used for marker-assisted selection of growth traits among goats.

Physiological, haematological and electroencephalographic responses to heat stress in Katjang and Boer goats

The present study aimed to determine the effect of repeated heat stress on serum levels of cortisol (CORT), acute phase proteins (APP) and heat shock protein (HSP) 70, haematological indicators, and electroencephalographic (EEG) response in the native Katjang and exotic Boer goats. Six female Katjang (15.7 kg ± 0.68) and six female Boer (16.8 kg ± 1.16) goats aged 5 to 6 months old were exposed to 38 ± 1℃ for 8 h, and the procedure was repeated at three different weeks (weeks 1, 2 and 3). Measurements of rectal temperatures and EEG activity and collection of blood samples were conducted before heat exposure (0 h), immediately after the heat exposure (8 h), and 8 h after completion of heat exposure (16 h) (recovery period). The current results revealed that the Boer animals had significantly higher rectal temperatures (RT), haemoglobin (Hb) and packed cell volume (PCV) counts than their Kajang counterparts. There were significant breed × stage of heat treatment (SHT) × week of heat treatment (WHT) interactions for neutrophil to lymphocyte ratios (NLR). In general, the Katjang animals had elevated NLR compared to those of Boer. The Boer goats had reduced capacity to express serum HSP70 compared to their Katjang counterparts following the heat challenge at week 3. Boer goats demonstrated higher delta waves than the Katjang group, which suggested the former were more stressed following the heat exposure. Breed had a negligible effect on CORT, APP, WBC counts and backfat thickness. Our findings suggested that the Katjang breed, as measured by RT, HB and PCV count, and EEG activity, could be more tolerant to heat stress than Boer. The Katjang goats showed higher HSP70 expression than their Boer counterparts, suggesting improved thermoregulation in the former.

Seasonal Changes in the Antioxidant Activity and Biochemical Parameters of Goat Milk

Goats are ubiquitous, including in hot and dry regions, while also being very sensitive to climate fluctuations, expressed in temperature differences. This affects their productivity and milk quality. Adaptation to heat requires high energy costs, affects "neurohumoral" regulation and is accompanied by oxidative stress with the increased production of free radicals. The aim was to study the main biochemical parameters of goat milk and its antioxidant activity depending on the season of the year. Sampling was carried out in April, June, August and October. Analysis of the biochemical components and antioxidant activity of goat milk was performed using modern analytical systems. From spring to autumn, the mass fraction of true or crude proteins in goat milk increased by 14.6-63.7% or by 12.3-52.1%, and the mass fraction of caseins also increased by 13.6-60.6%. For vitamin C level and the total amount of water-soluble antioxidants, a pronounced gradual decrease from spring to autumn was observed. In the summer period, a small increase in the carotene level in milk (by 3.0-6.1% compared to April) was established. Vitamin A content increased by 86.5% (June) or by 70.3% (October) compared to April. Thus, the numerous significant changes in the major parameters of goat's milk depending on the season were revealed.

Effects of management strategies on animal welfare and productivity under heat stress: A synthesis

Climate change includes different dramatic events, and among them, heat stress exposition is the strongest phenomenon affecting the livestock sector. The effects of heat stress events on animal welfare are complex and the economic impacts for the livestock sector are relevant. Management measures may contribute to improve the resilience to heat stress, but the extent to which they impact on livestock performances and management strategies depend on the magnitude of the stress conditions. Through a pioneering synthesis of existing knowledge from experiments conducted in controlled conditions, we show that management strategies, both adaptation and mitigation measures, halved the negative impacts on the ruminants' performances and welfare induced by heat stress, but the efficacy is low in extreme conditions, which in turn are more and more frequent. These novel findings emphasize the need to deepen research on more effective adaptation and mitigation measures.

Influence of goat management systems on hematological, oxidative stress profiles, and parasitic gastrointestinal infection

Background and Aim: Good management in goats is known for good quality health and increasing productivity. The physiological change studies in goats are limited despite some existing studies on the relationship of various patterns to growth rates. This study aimed to determine the hematological parameters, oxidative stress, and parasitic infection in three management systems in Thai native goats. Materials and Methods: A total of 18 male goats were randomly assigned to the three systems: The free-range model (FREE), the semi-intensive model (SEMI), and the kept-in-a-cage model (BARN) for 35 days. Blood, fecal sampling, and weight data were collected and monitored every 5 days for analysis. Results: No statistical differences were found in the FREE and SEMI groups, but significance was observed in the BARN group. The body weight of the goats gradually reduced from 13.0 ± 2.44 kg to 10.18 ± 2.61 kg (mean ± standard deviation). In contrast, the significantly increasing red blood cells, packed-cell volume, white blood cells, neutrophil-to-lymphocyte (N/L) ratio, cortisol hormone, and antioxidation profiles were observed to be higher in BARN than in FREE and SEMI groups. The intensity of the parasite eggs was remarkably significant. It was observed in the BARN group between the beginning and end of the experiment (supported by a high level of eosinophils). Conclusion: These data can be applied for the realistic evaluation and improvement of management practices, especially fully restrained management (BARN) for monitoring the health status of goats. Keywords: goat, hematology values, management systems, oxidative stress, parasites.

Characterization of sinoatrial automaticity in Microcebus murinus to study the effect of aging on cardiac activity and the correlation with longevity

Microcebus murinus, or gray mouse lemur (GML), is one of the smallest primates known, with a size in between mice and rats. The small size, genetic proximity to humans and prolonged senescence, make this lemur an emerging model for neurodegenerative diseases. For the same reasons, it could help understand how aging affects cardiac activity. Here, we provide the first characterization of sinoatrial (SAN) pacemaker activity and of the effect of aging on GML heart rate (HR). According to GML size, its heartbeat and intrinsic pacemaker frequencies lie in between those of mice and rats. To sustain this fast automaticity the GML SAN expresses funny and Ca²⁺ currents (I_f, I_Ca,L and I_Ca,T) at densities similar to that of small rodents. SAN automaticity was also responsive to β-adrenergic and cholinergic pharmacological stimulation, showing a consequent shift in the localization of the origin of pacemaker activity. We found that aging causes decrease of basal HR and atrial remodeling in GML. We also estimated that, over 12 years of a lifetime, GML generates about 3 billion heartbeats, thus, as many as humans and three times more than rodents of equivalent size. In addition, we estimated that the high number of heartbeats per lifetime is a characteristic that distinguishes primates from rodents or other eutherian mammals, independently from body size. Thus, cardiac endurance could contribute to the exceptional longevity of GML and other primates, suggesting that GML's heart sustains a workload comparable to that of humans in a lifetime. In conclusion, despite the fast HR, GML replicates some of the cardiac deficiencies reported in old people, providing a suitable model to study heart rhythm impairment in aging. Moreover, we estimated that, along with humans and other primates, GML presents a remarkable cardiac longevity, enabling longer life span than other mammals of equivalent size.

Pregnancy Toxemia in Ewes: A Review of Molecular Metabolic Mechanisms and Management Strategies

Pregnancy toxemia is a nutritional metabolic disease during late gestation in small ruminants. The condition is characterized by disorders in carbohydrate and fat metabolism. Obese and multiparous ewes are particularly susceptible to pregnancy toxemia, which may lead to maternal death, abortion, or premature birth. Highly productive multiparous meat ewes are major breeding animals, which has led to an increased incidence of the disease. However, the pathogenesis of pregnancy toxemia remains unclear and adequate disease prevention and treatment strategies are absent. Investigating the pathogenesis of pregnancy toxemia, especially the metabolic pathways of hepatic lipids, is key to an improved understanding of the condition. This review provides a snapshot of the genes that are associated with lipid metabolism in the ovine liver, including genes involved in fatty acid oxidation, acetyl coenzyme metabolism, and triglyceride synthesis; describes the interrelationships between these genes; and summarizes the diagnosis, prevention, and treatment of pregnancy toxemia.

Combination of nanoparticle green tea extract in tris-egg yolk extender and 39 °c thawing temperatures improve the sperm quality of post-thawed Kacang goat semen

Kacang goats are small ruminants produced by low-income households in smallholder and farm to reduce poverty and prevent undernutrition. Studies to find a cryopreservation protocol for Kacang goat semen are expected to multiplication of genetically superior animals selected by the paternal lineage. This study evaluated the effect of thawing temperature and supplementation of the green tea extract nanoparticle in skim milk-egg yolk (SM-EY) extender on post-thaw sperm quality of Kacang goat semen. Six ejaculates of Kacang goat were diluted in SM-EY supplemented or not (control group) with 0.001 mg/mL NPs GTE. The diluted semen was packaged with 0.25 mL straws (insemination dose: 60x10⁶ sptz/mL) and cryopreserved. Then, six samples of the control group and NPs GTE groups were thawed at 37°C or 39°C sterile water for 30 s and submitted to sperm quality evaluations. The sperm viability, motility, and intact of the plasma membrane (IPM) were higher (p<0.05) in NPs GTE group than control group. In contrast, the NPs GTE group presented lower (p<0.05) malondialdehyde levels and sperm DNA fragmentation (SDF) compared with the control group. The catalase levels were not significantly different (p > 0.05) between the control and NPs GTE groups. Thawing at 39°C resulted in higher (p<0.05) sperm viability, motility, and IPM than thawing at 37°C. However, thawing at 39°C group presented lower (p<0.05) malondialdehyde levels compared with thawing at 37°C. SDF and catalase levels were similar (p>0.05) between thawing at 37°C and thawing at 37°C. In conclusion, supplementation of 0.001 mg/mL of NPs GTE in SM-EY extender and thawing temperature of 39°C resulted in a better quality of frozen-thawed Kacang goat semen.

The profile of HSPA1A gene expression and its association with heat tolerance in crossbred cattle and the tropically adapted dwarf Vechur and Kasaragod

Certain livestock breeds are adapted to hot and humid environments, and these breeds have genetics that could be useful in a changing climate. The expression of several genes has been identified as a useful biomarker for heat stress. In this study, the responses to heat exposure of heat-tolerant Vechur and Kasaragod cattle found in Kerala state in India (also known as dwarf Bos taurus indicus) were compared to crossbred cattle (crosses of Bos t. taurus with Bos t. indicus). At various time points during heat exposure, rectal temperature and the expression of HSPA1A were determined, and the relationship between them was characterized. We characterized HSPA1A mRNA in Vechur cattle and performed molecular clock analysis. The expression of HSPA1A between the lineages and at different temperature humidity index (THI) was significant. There were significant differences between the expression profiles of HSPA1A in Kasaragod and crossbred (p < 0.01) and Vechur and crossbred (p < 0.01) cattle, but no significant difference in expression was observed between Vechur and Kasaragod cattle. The genetic distance between Vechur, B. grunniens, B. t. taurus, and B. t. indicus was 0.0233, 0.0059, and 0.007, respectively. The genetic distance between Vechur and the Indian dwarf breed Malnad Gidda was 0.0081. A molecular clock analysis revealed divergent adaptive evolution of Vechur cattle to B. t. taurus, with adaptations to the high temperatures and humidity that are prevalent in their breeding tract in Kerala, India. These results could also prove useful in selecting heat-tolerant animals using HSPA1A as a marker.

Influence of breed, production system and fecundity on serum antioxidant profiles of goats reared in the tropical Island conditions

The present study assessed the physiological antioxidant status of goats reared under the humid tropical island ecosystem of the Andaman and Nicobar Islands (ANI). From 2019 to 2020, 25 multiparous non-pregnant does with three to six kidding records maintained in the organized farm of Central Island Agricultural Institute (CIARI) and farmer’s field flocks from South Andaman district were selected for the study. Antioxidant markers such as total antioxidant capacity (TAC), superoxide dismutase (SOD), TG (Total glutathione) and catalase (CAT) were analyzed in blood serum with respect to rearing systems, breeds and level of fecundity. Correlation analyses of all dependent variables were performed using Pearson’s correlation. The endogenous antioxidant systems, viz. CAT, TG and SOD was non-significant with respect to rearing systems, breeds and fecundity. Similarly, TAC was non-significant among the breeds and with fecundity; however, semi-intensively managed goats showed significantly higher values than goats under the extensive condition. Correlation analysis showed that CAT was positively correlated with SOD and negatively correlated with TAC. TG showed no correlation with any of the studied antioxidants. Regression analysis of CAT as dependent variable and SOD and TAC as independent variables showed significance. It is concluded that values of antioxidant in the study can be considered as a baseline data for the ALG and other goat breeds of Andaman and Nicobar Islands and other islands or topographies with similar ecosystems for further studies.

HSP expression depends on its molecular construction and different organs of the chicken: a meta-analysis

Heat shock proteins (HSPs) expression protect the cell from stress, this expression varies on tissue and stress level. Here, we investigated the structure and functional expression of HSPs in different chicken organs using meta-analysis. A total of 1253 studies were collected from three different electronic databases from January 1, 2015 to February 1, 2022. Of these studies, 28 were selected based on the specific criteria for this meta-analysis. The results for the expression of HSPs and the comparative expression of HSPs (HSP90, HSP70, and HSP60) in different chicken organs (brain, heart, liver, muscle, and intestine) were analyzed using the odds ratio or the random-effects model (REM) at a confidence interval (CI) of 95%. Compared to the thermoneutral groups, heat stress groups exhibited a significant (P < 0.01) change in their HSP70 expression in the chicken liver (8 trials: REM = 1.41, 95% CI: 0.41, 4.82). The expression of different HSPs in various chicken organs varied and the different organs were categorized according to their expression levels. HSP expression differed among the heart, liver, and muscle of chickens. HSPs expression level depends on the structure and molecular weight of the HSPs, as well as the type of tissue.

Reducing the Fermentability of Wheat with a Starch Binding Agent Reduces Some of the Negative Effects of Heat Stress in Sheep

The objective of this study was to investigate the effects of reducing the fermentability of grains on thermoregulatory responses in heat stressed (HS) lambs. To achieve this, wheat grain treated with a commercial starch binding agent, Bioprotect, is compared to maize, which has already demonstrated effects in ameliorating heat stress-induced thermoregulation responses and untreated wheat grains. An initial in vitro experiment was conducted to examine cumulative gas production from the fermentation of wheat grain with different dosages of the commercial starch binding agent, Bioprotect. Based on the in vitro results, an in vivo lamb experiment was conducted using 24 Merino lambs (1 year old; 42.6 ± 3.6 kg BW). The lambs were offered one of three dietary treatments: a wheat-based diet (WD), a Bioprotect treated wheat-based diet (BD), and a maize-based diet (MD). Three successive 1-week experimental periods were conducted with lambs from all dietary groups (P1, P2, and P3). During P1, lambs were exposed to a TN environment and fed a 1.7× Maintenance feed intake (MF) level; in P2, lambs were kept in a HS environment and fed a 1.7× MF level; and in P3, animals were kept in a HS environment and fed a 2× MF level. The in vitro experiment revealed a reduction in cumulative gas production (p < 0.05) from the Bioprotect treated wheat compared to untreated wheat samples. In the in vivo component of the study, the replacement of wheat with maize or 2% Bioprotect-treated wheat reduced the respiration rate (p < 0.001) and heart rate (p ≤ 0.01) of lambs during HS. There was a reduction in the concentration of blood gas variables such as a base excess of blood (BE(b)) and extracellular fluid (BE(ecf)), bicarbonate (CHCO3−), the partial pressure of carbon dioxide (pCO2), the total concentration of carbon dioxide (ctCO2), and sodium (Na+) (p ≤ 0.001 for all) during the periods of HS compared to the thermoneutral conditions. Moreover, BD- and MD-fed lambs had a higher blood potassium concentration (K+) than the WD-fed lambs (p = 0.008). The results of the present study suggest that Bioprotect can be a viable feed treatment strategy for treating rapidly fermentable grains such as wheat to alleviate the effects of HS. Further, Bioprotect-treated wheat could be an option to replace maize in concentrate rations in jurisdictions where maize is cost-prohibitive or unavailable.

The Impact of Curcumin on Growth Performance, Growth-Related Gene Expression, Oxidative Stress, and Immunological Biomarkers in Broiler Chickens at Different Stocking Densities

Simple Summary

The primary goal of global poultry production is to optimize the amount of chicken produced per square meter of floor area. Consequently, stocking density (SD) and curcumin supplementation on broiler performance were investigated. Our results revealed that supplemental curcumin improved birds’ growth, behaviours, and immunity by lowering oxidative stress, enhancing humoral immune response, and modulating the suppression of growth-related gene expressions in broilers raised in high stocking density circumstances.

Abstract

Curcumin’s antioxidant properties reduce free radicals and may improve broiler growth. Therefore, the influence of stocking density (SD) and administration of curcumin in the diet on broiler performance was explored to clarify the impact of HSD and curcumin on the performance of growth, behavioural patterns, haematological, oxidant/antioxidant parameters, immunity markers, and the growth-related genes expression in broiler chickens. A total of 200 broiler chickens (Cobb 500, 2-weeks old) were allotted into 4 groups; SD (moderate and high) and curcumin (100 and 200 mg/kg diet)-supplemented HSD, respectively. Behavioural observations were performed. After a 28-day experimental period, tissue and blood samples were collected for analysis. Expressions of mRNA for insulin-like growth factor-1 (IGF-1), growth hormone receptor (GHR), myostatin (MSTN), and leptin in liver tissues were examined. HSD birds exhibited lower growth performance measurements, haematological parameters, circulating 3,5,3-triiodothyronine and thyroxine levels, antioxidant activities (GSH-Px, catalase, superoxide dismutase), immunoglobulins (A, G, M), and hepatic GHR and IGF-1 expression values. However, HSD birds even had an increment of serum corticosterone, malondialdehyde, pro-inflammatory cytokine (TNF-a, IL-2, IL-6) levels, hepatic leptin and MSTN expression. Moreover, HSD decreased drinking, feeding, crouching, body care, and increased standing and walking behaviour. The addition of curcumin, particularly at a 200 mg/kg diet, alleviated the effect of HSD through amending growth-related gene expression in the chickens. In conclusion, curcumin can enhance birds’ growth performance, behavioural patterns, and immunity by reducing oxidative stress and up-regulating the growth-related gene expressions of broilers under stressful conditions due to a high stocking density.

Extensive Sheep and Goat Production: The Role of Novel Technologies towards Sustainability and Animal Welfare

Simple Summary

New technologies have been recognized as valuable in controlling, monitoring, and managing farm animal activities. It makes it possible to deepen the knowledge of animal behavior and improve animal welfare and health, which has positive implications for the sustainability of animal production. In recent years, successful technological developments have been applied in intensive farming systems; however, due to challenging conditions that extensive pasture-based systems show, technology has been more limited. Nevertheless, awareness of the available technological solutions for extensive conditions can increase the implementation of their adoption among farmers and researchers. In this context, this review addresses the role of different technologies applied to sheep and goat production in extensive systems. Examples related to precision livestock farming, omics, thermal stress, colostrum intake, passive immunity, and newborn survival are presented; biomarkers of metabolic diseases and parasite resistance breeding are discussed.

Abstract

Sheep and goat extensive production systems are very important in the context of global food security and the use of rangelands that have no alternative agricultural use. In such systems, there are enormous challenges to address. These include, for instance, classical production issues, such as nutrition or reproduction, as well as carbon-efficient systems within the climate-change context. An adequate response to these issues is determinant to economic and environmental sustainability. The answers to such problems need to combine efficiently not only the classical production aspects, but also the increasingly important health, welfare, and environmental aspects in an integrated fashion. The purpose of the study was to review the application of technological developments, in addition to remote-sensing in tandem with other state-of-the-art techniques that could be used within the framework of extensive production systems of sheep and goats and their impact on nutrition, production, and ultimately, the welfare of these species. In addition to precision livestock farming (PLF), these include other relevant technologies, namely omics and other areas of relevance in small-ruminant extensive production: heat stress, colostrum intake, passive immunity, newborn survival, biomarkers of metabolic disease diagnosis, and parasite resistance breeding. This work shows the substantial, dynamic nature of the scientific community to contribute to solutions that make extensive production systems of sheep and goats more sustainable, efficient, and aligned with current concerns with the environment and welfare.

Effect of heat stress on vital and hematobiochemical parameters of healthy dogs

Background and Aim:

Heat stress is a major challenge for animals, impairing their welfare and performance. This study aimed to determine the effect of heat stress on the vital and hematobiochemical parameters of healthy dogs.

Materials and Methods:

The experimental subjects comprised 10 dogs, encompassing seven males and three non-pregnant females between 2 and 3 years of age. Ambient temperature (AT) and relative humidity (RH) were recorded 2 hourly during the day and the temperature humidity index was calculated. Vital parameters [i.e., rectal temperature (RT), respiratory rate, and heart rate (HR)] were assessed and blood was collected from each dog daily for hematobiochemical analysis.

Results:

The RT (38.5±0.2°C) of dogs exposed to high AT and high RH (HA/HR) conditions was significantly (p<0.05) higher than that of dogs exposed to HA and low RH (LR) conditions (37.2±0.11°C). Under HA/HR conditions, packed cell volume, hemoglobin concentrations, and white blood cell counts were significantly lower than those of the same dogs exposed to HA/LR conditions. Conversely, under HA/HR conditions, the lymphocyte, monocyte, eosinophil, alanine aminotransferase, aspartate aminotransferase, and cortisol values were significantly higher (p<0.05) than the values obtained in dogs exposed to HA/LR conditions. Meanwhile, the alkaline phosphatase, urea, and glucose levels were significantly lower (p<0.05) in dogs exposed to HA/HR conditions.

Conclusion:

The exposure of healthy dogs to HA/HR conditions induced heat stress, which may have an adverse effect on their immune status, thereby affecting their health and welfare.