Resilience of Small Ruminants to Climate Change and Increased Environmental Temperature: A Review

Unveiling the Pre-Weaning Growth Performance and Some Reproductive Characteristics of Akkaraman and Central Anatolian Merino Sheep

This study evaluated growth and reproductive traits in two sheep breeds in Türkiye, Akkaraman (AKK) and Central Anatolian Merino (CAM), with a focus on the impact of non-genetic factors. Data were analysed from 21,414 AKK and 20,099 CAM lambs for birth weight (BW) and 27,528 AKK and 24,639 CAM lambs for weaning weight (WW), average daily weight gain (ADWG) and Kleiber ratio (KR) using a linear mixed model. AKK lambs showed a significantly higher mean BW (4.19 ± 0.01 kg) than CAM lambs (4.02 ± 0.01 kg) (p < 0.001), whereas CAM lambs had significantly higher WW, ADWG and KR (p < 0.001 for each trait). Fixed effects of sex, birth type, dam age, birth year, herd size and season significantly influenced all growth traits (p < 0.05). Male lambs demonstrated higher BW, WW, ADWG and KR than females (p < 0.001), and single-born lambs had significantly higher BW and WW than twins (p < 0.001). Dam age also influenced all growth traits, with lambs from younger dams tending to be heavier (p < 0.001). In terms of survival, AKK lambs exhibited a significantly higher survival rate (93.85%) than CAM lambs (89.50%) (p < 0.001). Conception rates were similar for both breeds (92.9% for AKK and 92.3% for CAM), whereas CAM lambs showed higher fecundity and litter size. These findings underscore the breed differences in growth and reproductive traits and highlight the importance of considering non-genetic factors to inform breed-specific management practices aimed at optimizing productivity.

Meta-Analysis of Dietary Tannins in Small Ruminant Diets: Effects on Growth Performance, Serum Metabolites, Antioxidant Status, Ruminal Fermentation, Meat Quality, and Fatty Acid Profile

Tannins are secondary metabolites naturally present in various plants as a defense mechanism. In animal nutrition, they play a dual role, acting as both antinutritional factors and bioactive agents, with potential benefits in nutrient metabolism and product quality. This meta-analysis aimed to evaluate the effects of dietary tannin on nutrient intake and digestibility, blood serum metabolite levels, growth performance, carcass characteristics, and meat quality in small ruminants. Ninety-seven studies were included in this meta-analysis. The effects of tannins were analyzed using a random-effects model to determine the weighted mean difference between treatments with tannins and the control (without tannins). Publication bias and heterogeneity between studies were explored, and meta-regression and subgroup analyses were performed. The results indicated that tannin significantly increased the intake of dry matter, crude protein, nitrogen (N), fecal N, and meat fatty acids (FA), such as C18:2 ω6, C18:3 ω3, C20:4 ω6, C20:5 ω3, total ω3 and ω6 FA, and total polyunsaturated FA (PUFA). However, NH3-N, urinary N, blood urea nitrogen, cold carcass weight, subcutaneous fat thickness, drip loss, and nutrient digestibility decreased. In conclusion, tannin in small ruminants did not affect animal productivity and antioxidative status, but mainly modified nitrogen metabolism and improved the fatty acid profile of meat.

Ecosystem Services Linked to Extensive Sheep and Goat Farming in Mountain Areas: A Global Literature Analysis Using Text Mining and Topic Analysis

Mountain ecosystems are unique and complex environments characterised by their high altitudes, steep slopes, and significant climatic variations [...].

Role of micronutrients in production and reproduction of farm animals under climate change scenario

Climate change poses significant challenges to livestock production worldwide. Wherein, it affects communities in developing nations primarily dependent on agriculture and animal husbandry. Its direct and indirect deleterious effects on agriculture and animal husbandry includes aberrant changes in weather patterns resulting in disturbed homeorhetic mechanism of livestock vis a vis indirectly affecting nutrient composition of feed and fodder. The nutritional stress (i.e. non-availability of nutrients in the required quantity and quality for particular livestock) is the critical factor affecting livestock performance, productivity, and reproductive efficiency. Nutritional stress may arise from both macro- and micro- nutrient imbalances; however, micronutrients are of paramount importance in climate change context due to their role in various vital functions of body namely, body metabolism, production, reproduction, and health. The micronutrients, minerals and vitamins, when supplied in adequate quantity and proportion aid in mitigating the stress induced by climate change on animals. Here, we tried to discuss the impact of climate change induced stresses on milk production, reproduction, and metabolic acclimation of heat-stressed animals. Furthermore, emphasis is given on the importance of dietary micronutrients management strategies to support livestock health and resilience during changing climatic conditions. By addressing the nutritional needs of livestock, farmers can achieve sustainability and well-being in livestock production under changing climatic condition.

Feed efficiency and resilience in dairy ewes subjected to a nutritional challenge

It is currently uncertain how selection of more efficient animals might impact other traits such as resilience (which, in this context, is defined as the ability of an animal to sustain or revert quickly to its previous production level and health status after a disturbance), especially in small ruminants. However, improving, or at least maintaining, resilience is of utmost importance to ensure livestock production in the face of external perturbances, which are expected to become more prevalent in the near future due to climate change and global instability. This study was conducted to investigate whether a nutritional challenge consisting of animals receiving only 70% of their voluntary feed intake (DMI) for 26 d, might differentially affect the response of high- and low-feed efficiency (FE) sheep. To meet this aim, residual feed intake (RFI), as a proxy of FE, was calculated in 40 lactating ewes fed a total mixed ration ad libitum. Using the RFI values, the ewes with the highest (H-FE; n = 8) and the lowest (L-FE; n = 8) FE were selected and subjected to the nutritional challenge. After the feed restriction, all sheep were again fed ad libitum for a further 25 d. Temporal patterns of variation in animal performance, ruminal fermentation and blood and milk metabolites in response to, and recovery from, the underfeeding were examined in H-FE versus L-FE. More efficient ewes (H-FE) tended to eat less than less efficient ewes (L-FE) for the same level of production. Linear regressions for DMI and milk yield data showed that time-series response to the challenge was comparable in L-FE and H-FE. Despite temporal changes due to underfeeding, both FE divergent groups displayed a similar response to, and recovery from, the challenge with no significant differences in the temporal patterns of variation of the parameters analyzed, except for a tendency to higher plasma glucose in the L-FE ewes. These results challenge the general hypothesis that more efficient animals would be less resilient, but further research is still needed on the relationship and possible trade-offs between high efficiency and resilience.

Evaluating reproduction traits in a crossbreeding program between indigenous and exotic sheep in semi-arid lands

Reproduction traits are important factors determining the efficiency of any sheep production system. This study evaluates the age at first lambing (AFL), lambing interval (LI), litter weight at birth (LBWT), litter weight at weaning (LWWT), birth weight of ewe (EBWT) and weaning weight of ewes (EWWT) in a crossbreeding program between the Red Maasai (RRRR) and Dorper sheep and their crosses, 75% Dorper and 50% Dorper (DDRR) breeds. All the traits significantly (P < 0.05) differed across breeds and season of birth of the ewe. LBWT and LWWT were significantly affected by the sex of the lamb, type of birth of the lamb and parity in which the lambs were born in. AFL and LI had very high environmental variances. Overall heritability estimates of AFL (0.09 ± 0.04) and LI (0.00 ± 0.01) were not significant from zero while the heritability estimates for EBWT (0.38 ± 0.04), EWWT (0.23 ± 0.03), LBWT (0.19 ± 0.03) and LWWT (0.09 ± 0.02) were significant (P < 0.05). The RRRR had the highest genetic gain for all traits while the DDRR had a higher genetic gain among the crosses. LI had negative genetic correlations with LBWT (-0.53 ± 0.08) and LWWT (-0.28 ± 19.59) while AFL had positive genetic correlations with LBWT (0.27 ± 0.46) and LWWT (0.31 ± 0.34). The phenotypic trends for AFL and LWWT showed a negative and positive association, respectively, with the rainfall index over the years. With proper farm management, improved reproduction performance of ewes is possible by indirect selection using LBWT and LWWT for the Red Maasai, Dorper and their crosses within the semi-arid lands.

Heat stress: a major threat to ruminant reproduction and mitigating strategies

Stress is an external event or condition that puts pressure on a biological system. Heat stress is defined as the combination of internal and external factors acting on an animal to cause an increase in body temperature and elicit a physiological response. Heat stress is a set of conditions caused by overexposure to or overexertion at excess ambient temperature and leads to the inability of animals to dissipate enough heat to sustain homeostasis. Heat exhaustion, heat stroke, and cramps are among the symptoms. For the majority of mammalian species, including ruminants, heat stress has a negative impact on physiological, reproductive, and nutritional requirements. Reproductive functions, including the male and female reproductive systems, are negatively affected by heat stress. It decreases libido and spermatogenic activity in males and negatively affects follicle development, oogenesis, oocyte maturation, fertilization, implantation, and embryo-fetal development in females. These effects lead to a decrease in the rate of reproduction and financial losses for the livestock industry. Understanding the impact of heat stress on reproductive tissues will aid in the development of strategies for preventing heat stress and improving reproductive functions. Modification of the microenvironment, nutritional control, genetic development of heat-tolerant breeds, hormonal treatment, estrous synchronization, timed artificial insemination, and embryo transfer are among the strategies used to reduce the detrimental effects of heat stress on reproduction. These strategies may also increase the likelihood of establishing pregnancy in farm animals.

Applications of Next-Generation Sequencing Technologies and Statistical Tools in Identifying Pathways and Biomarkers for Heat Tolerance in Livestock

The climate change-associated abnormal weather patterns negatively influences the productivity and performance of farm animals. Heat stress is the major detrimental factor hampering production, causing substantial economic loss to the livestock industry. Therefore, it is important to identify heat-tolerant breeds that can survive and produce optimally in any given environment. To achieve this goal, a clearer understanding of the genetic differences and the underlying molecular mechanisms associated with climate change impacts and heat tolerance are a prerequisite. Adopting next-generation biotechnological and statistical tools like whole transcriptome analysis, whole metagenome sequencing, bisulphite sequencing, genome-wide association studies (GWAS), and selection signatures provides an opportunity to achieve this goal. Through these techniques, it is possible to identify permanent genetic markers for heat tolerance, and by incorporating those markers in marker-assisted breeding selection, it is possible to achieve the target of breeding for heat tolerance in livestock. This review gives an overview of the recent advancements in assessing heat tolerance in livestock using such 'omics' approaches and statistical models. The salient findings from this research highlighted several candidate biomarkers that have the potential to be incorporated into future heat-tolerance studies. Such approaches could revolutionise livestock production in the changing climate scenario and support the food demands of the growing human population.

Climate change impacts on livestock in Brazil

Brazilian livestock provides a significant fraction of the food consumed globally, making the country one of the largest producers and exporters of meat, milk and eggs. However, current advances in the production of protein from Brazilian animal origin may be directly impacted by climate change and the resulting biophysical effects. Therefore, it is strategically consistent to develop measures to deal with the resulting environmental heat stress on domesticated animal species, especially the need in developing countries. This work aims to (1) evaluate the impacts of climate change on livestock (cattle-dairy, cattle-beef, goats, sheep, pigs, poultry-general) in different regions of Brazil and (2) discuss possible response strategies, associated with animal comfort and welfare. From our results, we can draw better strategies to mitigate the impacts of climate change on livestock production. The results presented show an increase of high heat stress in South and Southeast and an increase of extreme heat stress in North and Central-West areas of Brazil. The rise in extreme heat stress tends to occur mostly during spring and summer and tends to vary considering the different evaluated species. Within the evaluated species, the ones that seem to be more affected by climate changes are Poultry, pigs, cattle-beef and general (temperature-humidity index value). The differences between the results for the five geographic regions in Brazil suggests that different mitigation measures need to be considered to cope with future heat stress in livestock. To ensure the long-term success of Brazil's influence on the global market for proteins of animal origin, it must achieve sustainable production systems more intensively.

The interrelationship between macrominerals and heat stress in ruminants: current perspectives and future directions - a review

Macromineral imbalances in ruminants, particularly in tropical and subtropical regions, pose a significant challenge to production sustainability and profitability. Heat stress exacerbates these imbalances, negatively impacting physiological functions and productivity. This review examines the effects of heat stress on macromineral levels in ruminants and the need for supplementation under such conditions. Heat stress lowers key macrominerals (Na+, K+, Cl-, Ca + 2, Mg + 2, inorganic P) and disrupts acid-base balance due to thermoregulatory responses and reduced feed intake. Supplementing macrominerals to the diet to achieve higher dietary cation-anion difference helps mitigate heat-related morbidity and maintains ruminant health and productivity. A more practical approach, such as sustained-release macromineral boluses in the rumen, is proposed to provide more consistent benefits. Further researches are warranted to optimize supplementation strategies and fully understand macromineral nutrition for heat-stressed ruminants.

Small ruminant farmers' feeding strategies to cope with climate change across five agroecological zones of Benin, West Africa

This study aimed to understand feeding strategies used by small ruminant farmers to cope with climatic change in the five contrasting agroecological zones (AEZ) of the Benin Republic and to identify the determinants of adopting these strategies. A semi-structured questionnaire was used to conduct interviews with 400 smallholder farmers in the rural areas of Benin. Data was collected on production system characteristics, farmers' perception of climatic changes' impacts on livestock production, and their coping strategies. Cross tabulations with Chi2 statistic and the non-parametric Kruskal Wallis test were used to compare farmers' perceptions and coping strategies between the five AEZ. Then, the binomial logistic regression was used to identify determinants of using a particular adaptive feeding strategy. The farmers perceived climatic changes as rainfall delays, increasing rainfall, less frequent drought periods during the rainy season, no change in sunshine duration, and no change in temperature. These changes negatively affected grassland biomass production (86.3 %, 86.3 % and 77.5 % of farmers in South Borgou, Plateau, Atacora chain AEZ, respectively) and water availability (100 %, 93.7 %, and 85 % of farmers in Oueme Valley, Plateau and Mekrou-penjari AEZ, respectively). Consequently, farmers mentioned decreased animal growth (58.8 % and 45 % of farmers in Plateau and South Borgou AEZ, respectively) and increased animal mortalities (43.8 % in Plateau AEZ). Farmers' current and future coping strategies varied significantly (p<0.05) among AEZ. These strategies included more diversification of feed resources used, more free wandering of animals, feeding intensification with supplements as current strategies, and new feed resource exploration and forage cultivation as future strategies. Logistic regression results showed that gender, education level, main activity, and the climatic and agroecological zones where the farm is located influenced the strategies used. The study showed that farmers understood climate change and its impact on production systems. In response, the common climate-smart feeding strategies adopted were mainly diversifying feed resources. Feed resources use strategies, and limitations to adopting these strategies, could be assessed in future studies.

Profiling the dynamic variations in body and scrotal surface temperatures of goats reared under stressful conditions using infrared thermography: Analytical perspectives

Infrared thermography (IRT) is an essential non-invasive method for analyzing surface temperature variations in animals, offering valuable insights into livestock stress responses. Despite their resilience, goats can face significant challenges under extreme conditions like heat-stress and water deprivation. This experiment aimed to delineate the dynamic variations in whole-body and scrotal surface temperatures in goats subjected to the combined impact of both conditions using IRT. Eight healthy Aardi bucks were exposed to three 72-h treatments: euhydration, dehydration, and rehydration. Continuous meteorological monitoring provided ambient-temperature, relative-humidity, and temperature-humidity index (THI) values. Surface temperatures were measured twice daily at 08:00 and 15:00, and thermal gradients between ambient and body or scrotal surface temperatures were computed. Based on the obtained mean THI values, the bucks experienced heat-stress throughout the experiment. Additionally, results revealed noticeable variations in both surface temperatures across treatments and time points, indicated by measures of central tendency, variability, shape descriptors, and frequency distribution of temperature. Morning measurements indicated lower temperatures and gradients under euhydration, while water deprivation led to higher temperatures and compromised thermal regulation. Conversely, afternoon data showed higher variability in temperature responses, highlighting the compounded effect of diurnal heat-stress and water deprivation. Although water-restoration mitigated some effects of deprivation, it did not fully restore thermal homeostasis to euhydrated levels. Thermal gradients further emphasized the goats' dynamic thermoregulatory mechanisms, which were compromised under water deprivation, particularly in the scrotal region, but were partially restored upon restoration. These findings demonstrate the effectiveness of IRT in assessing thermal responses in goats and underscore the importance of adequate hydration for maintaining thermal balance under heat-stress. The herein performed profiling provides valuable insights with implications for overall health, reproductive efficiency, productivity, and welfare in heat-stressed and water-deprived goats, which might offer a framework for future research on livestock adaptation to such challenging environmental conditions.

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.

Glucose Metabolism-Modifying Natural Materials for Potential Feed Additive Development

Glucose, a primary energy source derived from animals' feed ration, is crucial for their growth, production performance, and health. However, challenges such as metabolic stress, oxidative stress, inflammation, and gut microbiota disruption during animal production practices can potentially impair animal glucose metabolism pathways. Phytochemicals, probiotics, prebiotics, and trace minerals are known to change the molecular pathway of insulin-dependent glucose metabolism and improve glucose uptake in rodent and cell models. These compounds, commonly used as animal feed additives, have been well studied for their ability to promote various aspects of growth and health. However, their specific effects on glucose uptake modulation have not been thoroughly explored. This article focuses on glucose metabolism is on discovering alternative non-pharmacological treatments for diabetes in humans, which could have significant implications for developing feed additives that enhance animal performance by promoting insulin-dependent glucose metabolism. This article also aims to provide information about natural materials that impact glucose uptake and to explore their potential use as non-antibiotic feed additives to promote animal health and production. Further exploration of this topic and the materials involved could provide a basis for new product development and innovation in animal nutrition.

Nutritional Strategies to Alleviate Stress and Improve Welfare in Dairy Ruminants

Dairy ruminants provide a major part of the livestock and agriculture sectors. Due to the increase in world population and the subsequent increase in dairy product demands, the dairy sector has been intensified. Dairy farming intensification and the subsequent increase in animal nutritional demands and the increase in the average global temperature as well have subjected animals to various stress conditions that impact their health and welfare. Various management practices and nutritional strategies have been proposed and studied to alleviate these impacts, especially under heat stress, as well as during critical periods, like the transition period. Some of the nutritional interventions to cope with stress factors and ensure optimal health and production are the inclusion of functional fatty acids and amino acids and feed additives (minerals, prebiotics, probiotics, essential oils and herbs, phytobiotics, enzymes, etc.) that have been proven to regulate animals' metabolism and improve their antioxidant status and immune function. Thus, these nutritional strategies could be the key to ensuring optimum growth, milk production, and reproduction efficiency. This review summarizes and highlights key nutritional approaches to support the remarkable metabolic adaptations ruminants are facing during the transition period and to reduce heat stress effects and evaluate their beneficial effects on animal physiology, performance, health, as well as welfare.

Effect of birth type and sex on growth performance, wither height, humerus-radius bone dimensions, humerus-ulna growth plate width and selected hormone profile in growing Gurcu goat kids

OBJECTIVES

In this study, the effects of sex and birth type on growth performance, withers height (WH), radiographic measurements and selected hormone profiles in Gurcu goat kids were investigated.

METHODS

Twenty kids (single female = 5, single male = 5, twin female = 5, twin male = 5) were included in the study. Body weight (BW), WH, radiographic measurements (humerus length [HL], radius length [RL], proximal humerus epiphyseal plate width [HEP] and distal ulna epiphyseal plate width [UEP]) and biochemical analysis (for serum calcitonin, free triiodothyronine [FT3], free thyroxine [FT4], growth hormone [GH] and insulin-like growth factor-I [IGF-I]) were performed at 1, 3, 5, 7, 9 and 12 months of age.

RESULTS

BW was significantly higher in males starting from the seventh month compared to females (p < 0.05). HL was higher in males at seventh (p = 0.009) and ninth (p = 0.033) months, whereas RL was lower in twins at the third month (p = 0.021). UEP was wider in males at seventh (p = 0.008) and ninth (p = 0.036) months. Closure of HEP was observed in 65% of kids by the 12th month. Calcitonin was lower in twins at third (p = 0.045) and fifth (p = 0.006) months, with changes observed due to group and time effects (p < 0.05), whereas other hormones only changed with time (p < 0.05). Positive correlations were observed between BW, WH, HL, RL and IGF-I. There was a negative correlation between BW, WH, HL, RL, IGF-I and HEP, UEP, calcitonin, FT3, FT4, GH.

CONCLUSION

Sex and birth type in Gurcu goat kids may have an impact on growth performance, radiographic measurements and certain hormonal profiles.

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.

Association analysis of HSP90AA1 polymorphism with thermotolerance in tropically adapted Indian crossbred cattle

Raising cattle is a lucrative business that operates globally but is confronted by many obstacles, such as thermal stress, which results in substantial monetary losses. A vital role of heat shock proteins (HSPs) is to protect cells from cellular damage. HSP90 is a highly prevalent, extremely adaptable gene linked to physiological resilience in thermal stress. This study aimed to find genetic polymorphisms of the HSP90AA1 gene in Karan Fries cattle and explore their relationship to thermal tolerance and production traits. One SNP (g.3292 A > C) was found in the Intron 8 and three SNPs loci (g.4776 A > G, g.5218T > C and g.5224 A > C) were found in the exon 11 of 100 multiparous Karan Fries cattle. The association study demonstrated that the SNP1-g.3292 A > C was significantly (P < 0.01) linked to the variables respiratory rate (RR), heat tolerance coefficient (HTC) and total milk yield (TMY (kg)) attributes. There was no significant correlation identified between any of the other SNP sites (SNP2-g.4776 A > G; SNP3-g.5218T > C; SNP4-g.5224 A > C) with the heat tolerance and production attributes in Karan Fries cattle. Haploview 4.2 and SHEsis software programs were used to analyse pair linkage disequilibrium and construct haplotypes for HSP90AA1. Association studies indicated that the Hap3 (CATA) was beneficial for heat tolerance breeding in Karan Fries cattle. In conclusion, genetic polymorphisms and haplotypes in the HSP90AA1 were associated with thermal endurance attributes. This relationship can be utilized as a beneficial SNP or Hap marker for genetic heat resistance selection in cow breeding platforms.

Infectious disease responses to human climate change adaptations

Many recent studies have examined the impact of predicted changes in temperature and precipitation patterns on infectious diseases under different greenhouse gas emissions scenarios. But these emissions scenarios symbolize more than altered temperature and precipitation regimes; they also represent differing levels of change in energy, transportation, and food production at a global scale to reduce the effects of climate change. The ways humans respond to climate change, either through adaptation or mitigation, have underappreciated, yet hugely impactful effects on infectious disease transmission, often in complex and sometimes nonintuitive ways. Thus, in addition to investigating the direct effects of climate changes on infectious diseases, it is critical to consider how human preventative measures and adaptations to climate change will alter the environments and hosts that support pathogens. Here, we consider the ways that human responses to climate change will likely impact disease risk in both positive and negative ways. We evaluate the evidence for these impacts based on the available data, and identify research directions needed to address climate change while minimizing externalities associated with infectious disease, especially for vulnerable communities. We identify several different human adaptations to climate change that are likely to affect infectious disease risk independently of the effects of climate change itself. We categorize these changes into adaptation strategies to secure access to water, food, and shelter, and mitigation strategies to decrease greenhouse gas emissions. We recognize that adaptation strategies are more likely to have infectious disease consequences for under-resourced communities, and call attention to the need for socio-ecological studies to connect human behavioral responses to climate change and their impacts on infectious disease. Understanding these effects is crucial as climate change intensifies and the global community builds momentum to slow these changes and reduce their impacts on human health, economic productivity, and political stability.

Morphological and physiological features in small ruminants: an adaptation strategy for survival under changing climatic conditions

Climate change due to natural human activity is a significant global phenomenon affecting the sustainability of most countries' livestock industries. Climate change factors such as ambient temperature, relative humidity, direct and indirect sun radiation, and wind have significant consequences on feed, water, pasture availability, and the re-emergence of diseases in livestock. All these variables have a considerable impact on livestock production and welfare. However, animals' ability to respond and adapt to changes in climate differs within species and breeds. Comparatively, small ruminants are more adaptive to the adverse effects of climate change than large ruminants in terms of reproduction performance, survival, production yield, and resistance to re-emerging diseases. This is mainly due to their morphological features against harsh climate effects. Tropical breeds are more adaptive to the adverse effects of climate change than small temperate ruminants. However, the difference in morphological characteristics towards adaptation to the impact of climate change will guide the development of suitable policies on the selection of breeding stock suitable for different regions in the world. The choice of breeds based on morphological features and traits is an essential strategy in mitigating and minimizing the effects of climate change on small ruminants' production and welfare. This review highlights the adaptive morphological features within and among breeds of small ruminants toward adaptation to climate change.

Determinants of meat and milk production of Awassi sheep in Syria: A Cobb-Douglas production function estimation approach

Awassi is a fat-tailed sheep breed, and the best breed in Syria is famous. Awassi sheep are Syria's main source of red meat and milk production. In this study, we estimated the influence of various factors on sheep meat and milk production using time-series data from 1961 to 2020. This study employed the Cobb-Douglas production function to analyze the data. The results obtained indicate that Awassi meat production in Syria was positively and significantly influenced by carcass weight (p < 0.001) and quantity of slaughtered sheep (p < 0.001), with elasticity coefficients of 0.994 and 1.000, respectively. The model results show that raw milk yield and milk animals have a positive and significant influence on milk production at the 0.1 % significance level, with an elasticity coefficient of 0.998. However, climatic factors (precipitation and temperature) have a significant effect and negative influence on milk production at the 1 % and 5 % significance levels, respectively. This result sheds light on the policies and procedures the government should implement to develop sheep production in Syria. Therefore, it can be stated that policymakers should enhance the quality and productivity characterization of sheep through the implementation of breeding programs, improve grazing potential, and protect natural pastures. Furthermore, feed rations should be supported to help breeders overcome the effects of drought and high feed prices.

The comparative advantage of urban goat production

BACKGROUND

Urban agriculture significantly contributes to food security. The two primary components of urban agriculture are livestock production and horticulture. The goat, Capra hircus, is one of the commonly raised food animals. Goats can be used to generate income, produce milk, meat, skins, furs (hairs) and manure and provide various sociocultural and ecological services.

OBJECTIVES

This study evaluates the significance of urban goat production and recommends ways to lessen the adverse impacts of urban goat production.

METHODS

This report involved an in-depth interview with seven key informants in Adama and Addis Ababa cities.

RESULTS

Goats can thrive in limited urban open spaces, scavenge leftovers from homes and open markets and browse on open public land. Goats can be incorporated into urban agriculture, in so doing contributing to a circular economy. Goats can thrive on a limited supply of water and feed and require less care and space. Goat farming is used to mitigate the adverse impact of climate change. Goats are naturally active, which makes them better at avoiding traffic accidents. Goats can be used to control bush encroachment. Goat farming in cities improves land use efficiency and food security. Being friendly animals, goats can be utilized to play with kids, and they can be a basic piece of metropolitan ecotourism. However, goats can harm urban green spaces; therefore, to avoid issues of this kind, goat production must be zoned.

CONCLUSIONS

Urban goat farming could add a new dimension to urban food security. Extensive pieces of empirical evidence need to be generated to enhance the adoption of urban goat farming.

Behavioral thermoregulation in primates: A review of literature and future avenues

Primates face severe challenges from climate change, with warming expected to increase animals' thermoregulatory demands. Primates have limited long-term options to cope with climate change, but possess a remarkable capacity for behavioral plasticity. This creates an urgency to better understand the behavioral mechanisms primates use to thermoregulate. While considerable information exists on primate behavioral thermoregulation, it is often scattered in the literature in a manner that is difficult to integrate. This review evaluates the status of the available literature on primate behavioral thermoregulation to facilitate future research. We surveyed peer-reviewed publications on primate thermoregulation for N = 17 behaviors across four thermoregulatory categories: activity budgeting, microhabitat use, body positioning, and evaporative cooling. We recorded data on the primate taxa evaluated, support for a thermoregulatory function, thermal variable assessed, and naturalistic/manipulative study conditions. Behavioral thermoregulation was pervasive across primates, with N = 721 cases of thermoregulatory behaviors identified across N = 284 published studies. Most genera were known to utilize multiple behaviors (x ¯  = 4.5 ± 3.1 behaviors/genera). Activity budgeting behaviors were the most commonly encountered category in the literature (54.5% of cases), while evaporative cooling behaviors were the least represented (6.9% of cases). Behavioral thermoregulation studies were underrepresented for certain taxonomic groups, including lemurs, lorises, galagos, and Central/South American primates, and there were large within-taxa disparities in representation of genera. Support for a thermoregulatory function was consistently high across all behaviors, spanning both hot- and cold-avoidance strategies. This review reveals asymmetries in the current literature and avenues for future research. Increased knowledge of the impact thermoregulatory behaviors have on biologically relevant outcomes is needed to better assess primate responses to warming environments and develop early indicators of thermal stress.

Nutritional strategies, performance, digestibility, and carcass traits of Santa Ines and Rabo Largo breeds in a tropical climate

The aim of this study was to compare the performance, intake, digestibility, ruminal parameters, carcass traits, and the yield of commercial cuts of Santa Ines (SI) and Rabo Largo (RL) breeds fed diets with high or low roughage-to-concentrate ratio (R:C) under a tropical climate. Twenty lambs from each breed were individually housed in covered pens and fed the experimental diets for 58 days. The diets were formulated to meet the growth requirements of lambs with a roughage-to-concentrate ratio of 70:30 and 30:70. Significant interactions of breed × diet for nutrient intake were observed (P < 0.05), with SI lambs fed low R:C diet showing higher intake of dry matter, organic matter, crude protein, and total carbohydrates compared to RL lambs fed the same diet. SI lambs fed high R:C diet had higher intake of neutral detergent fiber than RL lambs (P < 0.05). SI lambs displayed better average daily gain and feed efficiency, regardless of diet (P < 0.05). Carcass traits and gastrointestinal components were influenced by breed and diet (P < 0.05). SI lambs fed low R:C diet showed higher subcutaneous fat thickness and better carcass finishing compared to RL lambs (P < 0.05). SI breed lambs exhibited better growth performance, carcass traits, and gastrointestinal characteristics, even when fed diets with a high roughage-to-concentrate ratio.

Seasonal variations in botanical and nutritive composition, forage availability and ingestive behavior of grazing goats in the semiarid region

The aim of this study was to assess how the different seasons of the year impact the botanical composition, availability, and quality of forage in the caatinga, as well as the frequency of ingestion and ingestive behavior of goats in a semi-arid region. The experiment used four crossbred castrated males, with an average weight of 30.2 ± 4.76 kg and an average age of 20 months. The experimental period lasted for 12 months, encompassing two rainy seasons and one dry season within this timeframe, with three replications (data collection) per season. All collected forage was categorized based on its stratum (herbaceous, woody, and litter), and a chemical composition analysis was conducted. The goats' behavior was assessed by observing variables such as feeding time, idleness, rumination, displacement, social interaction, and water intake. The findings revealed clear seasonality in both availability and quality of forage, consequently influencing the botanical composition of the goats' diet and their ingestive behavior. In addition, during the grazing period, the goats showed a shift grazing habit, in which idle and feeding peaks were alternated with increased displacement during the morning and rumination in the afternoon. The seasons of the year strongly impact the availability and nutritional quality of forage in the caatinga biome, consequently influencing the ingestive behavior and dietary composition of goats in this ecosystem.

Analysis of reproduction success, growth and milk trajectories and response to nutritional challenge in two Alpine goat lines selected on divergent longevity

This study aims to investigate whether the variation in reproduction success, growth, and milk trajectories is associated with different adaptive strategies in the short term (response to an acute nutritional challenge), using two Alpine goat lines. A total of 382 Alpine goats (179 low longevity (low_LGV) and 203 high longevity (high_LGV)), selected for divergent functional longevity from a commercial population, were monitored for 4 years and recorded for BW, reproduction and milking performance. Every year, an average of fifty primiparous goats were exposed to a 2-d nutritional challenge in early lactation. A polynomial model was used to analyse the lifetime trajectory of lactation and BW. A piecewise model was used to analyse the individual milk yield and responses of milk components to the nutritional challenges. The statistical analysis revealed that the two lines had a similar performance for total milk yield in the first lactation, BW at birth and at first kidding, litter size and weight, kidding interval and interval from the first insemination to conception. BW trajectories revealed that low_LGV goats had a greater BW in pregnancy but then lost more weight in early lactation compared to high_LGV goats, which showed a greater BW after kidding. Milk trajectories showed that the high_LGV goats had a higher initial milk yield, an earlier but less marked lactation peak and more persistency in milk production in late lactation than low_LGV goats. Except for milk protein content, quite similar response and recovery profiles of milk yield and milk fat content were observed during the challenge for both lines. The response to the challenge was positively correlated to the initial level of milk production in early lactation but negatively correlated with milk production decline after the peak. This finding suggests that the low_LGV goats were more adapted to allocate resources to meet an expected physiological change such as gestation and lactation. However, high_LGV goats allocate more than low_LGV goats for structural mass and may better cope with an unexpected environmental change such as nutritional deficit.

Hungarian indigenous Tsigai, a promising breed for excellent heat tolerance and immunity

The adverse effects of climate change on sheep farming have become more noticeable in recent decades. Extensive efforts have been made to untangle the complex relationship between heat tolerance, animal health, and productivity, also to identify a resilient and economically suitable breed for selection that can be resilient to future climate change conditions. Using quantitative real-time polymerase chain reaction (qRT-PCR), we observed the seasonal variations in the expression of several important genes related to heat stress and immunity (HSP70, IL10, TLR2, TLR4, and TLR8) in three of the most widely kept sheep breeds in Hungary: The indigenous Tsigai, Hungarian Merino, and White Dorper. We found that the seasonal stressor affected the relative gene expression of all genes in this study. Notably, The Hungarian indigenous Tsigai was the most robust breed adapted to the Hungarian continental (hot summer, cold winter) environment, with excellent thermotolerance and immunity. Furthermore, despite suffering from heat stress in the summer, Hungarian Merino maintained their robust immune system well throughout the year.

Relationship between feed efficiency and resilience in dairy ewes subjected to acute underfeeding

Selection of dairy sheep based on production levels has caused a loss of rusticity, which might compromise their future resilience to nutritional challenges. Although refocusing breeding programs toward improved feed efficiency (FE) is expected, more-efficient ewes also seem to be more productive. As a first step to examine the relationship between FE and resilience in dairy sheep, in this study we explored the variation in the response to and the recovery from an acute nutritional challenge in high-yielding Assaf ewes phenotypically divergent for FE. First, feed intake, milk yield and composition, and body weight changes were recorded individually over a 3-wk period in a total of 40 sheep fed a total mixed ration (TMR) ad libitum. Data were used to calculate their FE index (FEI, defined as the difference between the actual and predicted intake estimated through net energy requirements for maintenance, production, and weight change). The highest and lowest FE ewes (H-FE and L-FE groups, respectively; 10 animals/group) were selected and then subjected to the nutritional challenge (i.e., withdrawing the TMR and limiting their diet only to the consumption of straw for 3 d). Afterward, sheep were fed again the TMR ad libitum. Temporal patterns of variation in performance traits, and ruminal fermentation and blood parameters were examined. A good consistency between FEI, residual feed intake, and feed conversion ratio was observed. Results supported that H-FE were more productive than L-FE sheep at similar intake level. Average time trends of milk yield generated by a piecewise model suggest that temporal patterns of variation in this trait would be related to prechallenge production level (i.e., H-FE presented quicker response and recovery than L-FE). Considering all studied traits, the overall response to and recovery from underfeeding was apparently similar or even better in H-FE than in L-FE. This would refute the initial hypothesis of a poorer resilience of more-efficient sheep to an acute underfeeding. However, the question remains whether a longer term feed restriction might impair the ability of H-FE ewes to maintain or revert to a high-production status, which would require further research.

Impact of Heat Stress on Blood, Production, and Physiological Indicators in Heat-Tolerant and Heat-Sensitive Dairy Cows

Heat stress affects production and health in cows severely. Since it is difficult to define heat-tolerant animals, studies of response to heat stress are important for understanding dairy cows' health and production. However, information on the impact of heat stress on various indicators in heat-tolerant and heat-sensitive cows is sparse. This study aimed to investigate the effects of heat stress (HS) on blood, production, and physiological indicators in heat-tolerant and heat-sensitive cows. A total of 43 dairy cows were used from 9 May to 7 August 2021, under Temperature-Humidity Index (THI) measurements that ranged from 65.9 to 86.7. We identified cows that were tolerant or sensitive to HS based on the slope of the response of physiological and production traits against THI during the HS period by using a clustering method. After HS, serum glucose (Glu), cortisol (COR), 5-hydroxytryptamine (5-HT), and interleukin-6 (IL-6) levels of cows in the heat-tolerant group were lower than in the heat-sensitive group (p < 0.05). With THI as the predictor, the R2 for predicting respiration rate (RR) and body surface temperature (BT) in heat-tolerant cows was 0.15 and 0.16, respectively, whereas the R2 for predicting RR and BT in heat-sensitive cows was 0.19 and 0.18, respectively. There were low to moderate, positive correlations between RR, BT, and MY with THI, with Pearson correlation coefficients ranging from r = 0.11 to 0.4 in the heat-tolerant group, and from r = 0.24 to 0.43 in the heat-sensitive group. There was a low positive correlation between VT and THI, with a Spearman correlation coefficient of r = 0.07 in the heat-sensitive group. The heat-tolerant dairy cows had lower MY losses and had lower MY (p = 0.0007) in mixed models. Heat-tolerant cows with low-stress levels, through upregulating RR rapidly, increased their adaptability to thermal environments. They have better thermoregulation capability; the hypothalamic-pituitary-adrenal (HPA) axis regulated the thermoregulatory in animals by releasing a variety of neurotransmitters and hormones.

Blood Transcriptomic Analyses Reveal Functional Pathways Associated with Thermotolerance in Pregnant Ewes Exposed to Environmental Heat Stress

Environmental heat stress triggers a series of compensatory mechanisms in sheep that are dependent on their genetic regulation of thermotolerance. Our objective was to identify genes and regulatory pathways associated with thermotolerance in ewes exposed to heat stress. We performed next-generation RNA sequencing on blood collected from 16 pregnant ewes, which were grouped as tolerant and non-tolerant to heat stress according to a physiological indicator. Additional samples were collected to measure complete blood count. A total of 358 differentially expressed genes were identified after applying selection criteria. Gene expression analysis detected 46 GO terms and 52 KEGG functional pathways. The top-three signaling pathways were p53, RIG-I-like receptor and FoxO, which suggested gene participation in biological processes such as apoptosis, cell signaling and immune response to external stressors. Network analysis revealed ATM, ISG15, IRF7, MDM4, DHX58 and TGFβR1 as over-expressed genes with high regulatory potential. A co-expression network involving the immune-related genes ISG15, IRF7 and DXH58 was detected in lymphocytes and monocytes, which was consistent with hematological findings. In conclusion, transcriptomic analysis revealed a non-viral immune mechanism involving apoptosis, which is induced by external stressors and appears to play an important role in the molecular regulation of heat stress tolerance in ewes.

Coat color affects the resilience against heat stress impacts on testicular hemodynamics, reproductive hormones, and semen quality in Baladi goats

Drastic climatic changes threaten animal productivity and prolificacy, whose adaptability is governed by its pheno- and genotypic traits. This study was aimed at investigating the effect of coat color on the adaptability of goat bucks under heat stress conditions from the perspectives of testicular blood flow (TBF) and biometry, reproductive hormones, and semen quality. Twenty bucks (Capra hircus) bearing different coat colors were selected from a large flock and divided into four equal groups (n = 5 each) as follows: black coat (BC; 100% black), brown coat (BrC; 100% dark brown), white coat (WC; 100% white), white-black coat (WBC; 50-60% white). Bucks were examined for TBF [Doppler ultrasonography and serum nitric oxide (NO)], testosterone (T) and luteinizing hormone (LH), seminal plasma oxidative biomarkers [catalase (CAT), total antioxidant capacity (TAC), and malondialdehyde (MDA)], and sperm traits percentages [progressive motility (PM), viability (SV), normal morphology (NM), and sperm concentration (SC) once a week for seven consecutive weeks (W1-W7) in the summer season (temperature humidity index = 88.4-92.2). Specifically, at W3-W7, darker bucks (BC and BrC) testicular volume, testicular colored area, T, NO, CAT, TAC, PM, SV, NM, and SC (W7 only) differed significantly (P < 0.05) by decrease than the lighter ones (WC and WBC). Both Doppler indices and serum MDA concentrations were elevated (P < 0.05) at W3-W7 in the BC and BrC bucks compared to WC and WBC groups. In conclusion, bucks with lighter coats were more resistant to the negative effects of HS on TBF, seminal oxidative biomarkers, and semen quality.

Coat Color in Local Goats: Influence on Environmental Adaptation and Productivity, and Use as a Selection Criterion

This paper aims to review, systematically synthesize, and analyze fragmented information about the importance of coat color in local goats and its relationship with productivity and other important traits. Topics on current research on color expression are addressed, the relationship that has as a mechanism of environmental adaptation, its relationship with the production of meat, milk, and derivates, and the economic value of this characteristic. The use of this attribute as a tool to establish selection criteria in breeding programs based on results reported in the scientific literature is significant, particularly for low-income production systems, where the implementation of classic genetic improvement schemes is limited due to the lack of productive information, which is distinctive of extensive marginal or low scaled production systems around the world.

Dietary Betaine Impacts Metabolic Responses to Moderate Heat Exposure in Sheep

Dietary betaine supplementation can ameliorate physiological responses to heat exposure (HE) in sheep. This experiment measured metabolic responses to glucose (intravenous glucose tolerance, IVGTT), insulin (insulin tolerance test, ITT), and adrenocorticotropic hormone (ACTH) challenges in Merino ewes (n = 36, 39.7 kg) maintained at thermoneutral (TN, 21 °C) or HE (18-43 °C) and supplemented with either 0, 2, or 4 g/day dietary betaine (n = 6 per group). Sheep had ad libitum access to water and were pair-fed such that the intake of the TN sheep mimicked that of the HE sheep. After 21 days of treatment, sheep were fitted with jugular catheters and subjected to consecutive daily challenges (IVGTT, ITT, and ACTH, d 21-23, respectively), followed by skeletal muscle and subcutaneous adipose tissue biopsy collections for gene expression analysis (d 24). The HE-treated sheep had a greater insulin:glucose ratio (p = 0.033), a greater estimated homeostatic model assessment of insulin resistance (HOMAIR; p = 0.029), and a reduced revised quantitative insulin sensitivity check index (RQUICKI; p = 0.015). Sheep fed betaine (2 + 4 g/day) had a greater basal plasma insulin (p = 0.017) and a reduced basal non-esterified fatty acid (NEFA; p = 0.036) concentration, while the RQUICKI was reduced (p = 0.001) in sheep fed betaine. The results suggested that betaine supplementation alters lipid metabolism by potentially improving insulin signaling, although these responses differ between TN and HE conditions. There was no other impact of temperature or dietary treatments on the tissue gene expressions measured. Our results support the notion that betaine, in part, acts to modify lipid metabolism.

Space allowance impacts behavior, productivity, reproductivity and immunity of sheep-a review

Sheep is an important producing animal in subtropical and arid regions; however, sheep farming practices and welfare standards are still not well established. To move to either intensive or intensive sheep production, stocking density (animal/area, SD) is a significant factor that influencing the welfare and productivity of animals. However, there are discrepancies in space allowance standards for wool, meat, and dairy sheep at different stages. Thus, this review article sheds light on (1) the geographical distribution of wool, meat-type, and dairy sheep populations; (2) the effects of interaction among space allowances, housing systems, and group size on the social, feeding, and aggressive behaviors and human-sheep contact; (3) the effects of space allowance on wool, growth performance, and milk production of sheep; (4) the relationship between space allowance and reproductive performance; (5) the effects of stocking rate on immunity; and (6) suggestions to mitigate the stress and deleterious influences of SD on the productivity of sheep. In conclusion, the larger space allowance with access to an outdoor yard can improve social and feeding behaviors, meat and milk yield, and wool quality. Moreover, ewes are more sensitive to SD, so they should receive an adequate space allowance at each stage. The changes in behavioral responses of each sheep breed refer to their different requirements. Therefore, there is a need to determine the impact of housing aspects, especially space allowance and enrichment tools on the productive performance and welfare indices of sheep for implementing welfare-economic standards for sheep production.

Effects of Long-Term Cold Stress on Growth Performance, Behavior, Physiological Parameters, and Energy Metabolism in Growing Beef Cattle

This study aimed to evaluate the effects of a long-term cold environment on growth performance, physiological behavior, biochemical blood indexes, and hormone levels in Simmental cattle. Thirty Simmental crossbred bulls (weight = 350 ± 17 kg, 13-14 months old) were selected for two trials at autumn suitable temperatures (A-ST) and winter cold temperatures (W-CT) (15 cattle per season). The results showed that compared with the A-ST group, dry matter intake (p < 0.05) and feed:gain (p < 0.01) of the W-CT group increased, while body weight (p < 0.01) and average daily gain (p < 0.01) significantly decreased. Long-term cold stress also increased lying time (p < 0.01), feeding time (p < 0.05), and pulse rate (p < 0.01) in the W-CT group, while the rumen volatile fatty acids content (p < 0.01) and apparent digestibility of nutrients (p < 0.05) were significantly decreased. In terms of blood indicators, long-term cold stress increased the concentrations of glucose, glucose metabolic enzymes, glucocorticoids, triiodothyronine, and tetraiodothyronine in the plasma of the W-CT group (p < 0.05), but the levels of triglycerides, β-hydroxybutyrate, propionate, insulin, and growth hormone were decreased (p < 0.01). In summary, long-term cold stress may inhibit the digestive function of Simmental cattle and enhance the body's energy metabolism and stress hormone imbalance, ultimately damaging the normal growth and development of the body.

Genetic Markers Associated with Milk Production and Thermotolerance in Holstein Dairy Cows Managed in a Heat-Stressed Environment

Dairy production in Holstein cows in a semiarid environment is challenging due to heat stress. Under such conditions, genetic selection for heat tolerance appears to be a useful strategy. The objective was to validate molecular markers associated with milk production and thermotolerance traits in Holstein cows managed in a hot and humid environment. Lactating cows (n = 300) exposed to a heat stress environment were genotyped using a medium-density array including 53,218 SNPs. A genome-wide association study (GWAS) detected six SNPs associated with total milk yield (MY305) that surpassed multiple testing (p < 1.14 × 10^-6). These SNPs were further validated in 216 Holstein cows from two independent populations that were genotyped using the TaqMan bi-allelic discrimination method and qPCR. In these cows, only the SNPs rs8193046, rs43410971, and rs382039214, within the genes TLR4, GRM8, and SMAD3, respectively, were associated (p < 0.05) with MY305, rectal temperature (RT), and respiratory rate. Interestingly, these variables improved as the number of favorable genotypes of the SNPs increased from 0 to 3. In addition, a regression analysis detected RT as a significant predictor (R² = 0.362) for MY305 in cows with >1 favorable genotype, suggesting this close relationship was influenced by genetic markers. In conclusion, SNPs in the genes TLR4, GRM8, and SMAD3 appear to be involved in the molecular mechanism that regulates milk production in cows under heat-stressed conditions. These SNPs are proposed as thermotolerance genetic markers for a selection program to improve the milk performance of lactating Holstein cows managed in a semiarid environment.

Genome-Wide Scan of Wool Production Traits in Akkaraman Sheep

The objective of this study was to uncover the genetic background of wool quality, a production trait, by estimating genomic heritability and implementing GWAS in Akkaraman sheep. The wool characteristics measured included fibre diameter (FD) and staple length (SL) at the age of 8 months and yearling fibre diameter (YFD), yearling staple length (YSL) and yearling greasy fleece weight (YGFW) at 18 months of age. Animals were genotyped using the Axiom 50 K Ovine Genotyping Array. Maximum likelihood estimations of a linear mixed model (LMM) were used to estimate genomic heritability, where GWAS was conducted following a score test of each trait. Genomic heritability estimates for the traits ranged between 0.22 and 0.63, indicating that phenotypes have a moderate range of heritability. One genome- and six chromosome-wide significant SNPs were associated with the wool traits in Akkaraman lambs. Accordingly, TRIM2, MND1, TLR2, RNF175, CEP290, TMTC3, RERE, SLC45A1, SOX2, MORN1, SKI, FAAP20, PRKCZ, GABRD, CFAP74, CALML6 and TMEM52 genes as well as nine uncharacterized regions (LOC101118971, LOC105609137, LOC105603067, LOC101122892, LOC106991694, LOC106991467, LOC106991455, LOC105616534 and LOC105609719) were defined as plausible candidates. The findings of this study shed light on the genetics of wool quality and yield for the Akkaraman breed and suggests targets for breeders during systematic breeding programmes.

Heritability and environmental influence on pre-weaning traits in Kilis goats

Birth and weaning weights, average daily weight gain, and Kleiber ratio are important indicator traits in selection decision. The phenotypic expression of these traits is determined by the genetic background, environmental effects, and their interactions. The objective of this study was to estimate genetic parameters regarding birth (BW) and weaning weights (WW) and average daily weight gain (ADWG), Kleiber ratio (KR), and obtain the effects of sex, birth type, herd, and year. The data consisted of 2274 Kilis goats with pedigree information obtained from 53 bucks and 774 does in 4 generations. The restricted maximum likelihood (REML) procedure was conducted with an animal linear mixed model. Sex, birth type, herd, and year were found to be statistically significant (p value < 0.001) for all traits. Moderate direct heritabilities (h_a²) for BW, WW, ADW, and KR were found to be as 0.18 ± 0.03, 0.50 ± 0.04, 0.47 ± 0.04, and 0.37 ± 0.05, respectively. The proportion of maternal permanent environmental effect (c²) to the total phenotypic variance (σ²_p) was estimated as 0.00 ± 0.00, 0.12 ± 0.02, 0.11 ± 0.02, and 0.18 ± 0.03 for BW, WW, ADWG, and KR, respectively. The genetic, phenotypic, and environmental correlations between the pre-weaning growth traits were found to be ranging from - 0.02 to 0.99. Thus, our study suggests moderate heritabilities and positive and relatively high genetic correlations among the observed pre-weaning growth traits. These results have implications in terms of providing rapid genetic progress for these traits in breeding programs of Kilis goats.

Morphostructural Differences between the Historical Genetic Lines of the Spanish Merino Sheep

The Merino breed, which originates from Spain, is the most emblematic livestock breed in the world, since it is the first with a worldwide extension and has had an important impact on the genetic origin of several of the main current sheep populations. For this reason, it is of vital importance to typify the historical genetic lines of the original Spanish Merino breed and thereby ensure the conservation of its variability. In the present study, we used 337 purebred animals (males and females) registered in the Genealogical Book of the Native Merino Breed. All the animals were descendants of herds from six ancestral genetic lines (Maesso, Egea, Granda, López-Montenegro, Hidalgo, and Donoso). Significant differences were found in all the morphometric traits and indexes between the different genetic lines. Using discriminant analysis, 84% of the animals were classified correctly into their historical genetic lines. Furthermore, the distances between the lines, calculated by a cluster test, showed that Hidalgo, Maesso, and Donoso had the most clearly defined lines, while the Granda, López-Montenegro, and Egea lines were more similar to each other. All this demonstrates the rich genetic variability existing in the genuine gene pool of the Merino sheep breed.

Validation of SNP markers for thermotolerance adaptation in Ovis aries adapted to different climatic regions using KASP-PCR technique

A study on 51 SNPs belonging to 29 genes related to heat stress was carried out in 720 sheep from 17 different breeds adapted to different climates from Hungary, Bosnia and Herzegovina, Morocco and Romania, using Kompetitive Allele-Specific Polymerase Chain Reaction. Genotype frequency and the Hardy-Weinberg equilibrium were calculated, followed by a clustering using the Principal Component Analysis. We analyzed the polymorphisms in the following genes analyzed: HSPA12A, HSP90AA1, IL33, DIO2, BTNL2, CSN2, ABCG1, CSN1S1, GHR, HSPA8, STAT3, and HCRT. We emphasized on HSPA12A and HSPA8 genes as they were successfully genotyped in all studied flocks in which genotype frequency patterns were identified. Contrary to previous findings, the A allele for HSPA8 SNP was not observed in the heat tolerant breeds, being found exclusively in cold-tolerant breeds. The principal component analysis could not clearly differentiate the breeds, while plot concentration was slightly varied among the three groups, with HSP90AA1 and IL33 SNPs' loading values significantly contributing to PC1 and PC2. We confirmed previous works that the HSPA12A, HSPA8, HSP90AA1 and IL33 SNPs are potential candidate markers for thermotolerance adaptation in sheep. This research contributes to the genetic variability of SNPs for thermotolerance adaptability in sheep.

Genetic polymorphism in HSPB6 gene and their association with heat tolerance traits in Indian Karan Fries (Bos taurus x Bos indicus) cattle

Heat shock proteins (HSPs) act as a chaperone activity ensuring the folding, unfolding, and refolding of denatured proteins, which help in a protective role during thermal stress in dairy cattle. This study aimed to detect genetic variations of the HSPB6 gene and to determine their association with heat tolerance traits in Karan Fries cattle. Five single nucleotide polymorphisms (SNPs) (SNP 1-5) were reported in the Karan Fries cattle, which included three transitions viz. SNP1-g.161G > A, SNP2-g.436G > A, and SNP4-g.2152A > G and two transversions viz. SNP3-g.1743C > G, SNP5-g.2417A > T. The association analysis revealed that the three SNPs loci i.e., SNP1-g.161G > A, SNP2-g.436G > A, and SNP3-g.1743C > G were significantly (p < 0.01) associated with the respiration rate (RR) and rectal temperature (RT) (°C) traits. Furthermore, in the case of heat tolerance coefficient (HTC) trait was found significantly associated (p < 0.01) with SNPs loci i.e., SNP1-g.161G > A, SNP2-g.436G > A, and SNP3-g.1743C > G. The Hap 4 (GACAT) was found to more adaptable than cattle of other haplotypes as reflected by lower values of RR, RT and HTC. This study provides the first association analyses between the SNPs and haplotypes of HSPB6 gene and heat tolerance traits in Karan Fries cattle, which could be used as effective SNP markers in genetic selection for heat tolerance in cattle breeding program.

Are winter rangelands enough to satisfy the nutritional requirements of late-gestation transhumant goats in Patagonia?

Transhumant herds graze across two different rangeland types according to the season. Winter rangelands differ from summer rangelands in the amount and quality of available fodder, with the former being the less productive. In cold areas, winter rangeland has low forage quality where goats may suffer severe nutritional restrictions during gestation which lead to significant reproductive losses in the form of abortions and perinatal losses. In Argentinian northern Patagonia, the transhumant Criollo goat is a dual-purpose breed, producing both meat and cashmere and grazing on winter rangelands where they complete their reproductive cycle. Our objective was to evaluate to what extent the winter rangelands of northern Argentine Patagonia satisfy the nutritional requirements needed by Criollo transhumant goats during late gestating. We evaluated a study between 2010 and 2012 where we analysed the body weight and body condition score of the goats reaching the winter rangelands and before kidding. We also analysed the botanical composition of their diet, the quality forage (metabolizable energy, crude protein and digestibility) contribution offered by the species and the proportions of the nutritional requirements of the goats during the last third of gestation. Significantly, we found a decrease in body weight and body condition score in late gestation. In 2010, the goats’ diet showed a nutritional deficiency value of 0.6 Mcal/day metabolizable energy and 30.43 g/day crude protein; in 2011, a deficiency of 0.77 Mcal/day metabolizable energy and 65.48 g/day crude protein; and in 2012, a deficiency of 0.75 Mcal/day metabolizable energy and 55.41 g/day crude protein. Forage present 51, 52 and 48% digestibility in each year, respectively. We conclude that forage quality in winter rangelands in Argentinean Patagonia is not high enough to satisfy the nutritional requirements of Criollo transhumant goats during the last third of gestation. We recommend 550 g/day of an 80:20 mixture of corn:soy expeller supplementation during late gestation.

Relationship between thermal environment, thermoregulatory responses and energy metabolism in goats: A comprehensive review

Knowledge on heat stress of animals is key to developing management strategies to mitigate its effects on livestock production. Efficiency and profitability of production systems will certainly be challenged by the forecasted global temperature increase of 1.5 °C between 2030 and 2050. Goats are a resilient animal model, much less affected by climatic variations than average livestock. However, this statement is only true to a certain threshold, which, if exceeded, may affect energy metabolism of goats thus affecting respiratory frequency, heart pulse, evaporative thermolysis and rectal temperature, also altering on hormonal profile of animals, leading to behavioural changes such as altering feed and water intake and sheltering in the quest for homeothermic status. Dairy goat breeds, such as Saanen, are more sensitive to heat stress. Adaptations in nutritional and environmental management, as well as selecting better adapted breeds are strategic practices targeting the mitigation of effects of thermal stress of goats in farming systems. However, studies on effects of ambient temperature on energy and basal metabolisms of goats are scarce. This review aims to elucidate energetic and basal metabolism responses of goats under heat stress targeting the development of management strategies to mitigate heat stress in the farming systems and the conservation of genetic resources, adaptability, phenotypic plasticity, and basal heat production in different breeds.

Welfare of small ruminants during transport

In the framework of its Farm to Fork Strategy, the Commission is undertaking a comprehensive evaluation of animal welfare legislation. The present Opinion deals with the protection of small ruminants (sheep and goats) during transport. The main focus is on welfare of sheep during transport by road but other means of transport and concerns for welfare of goats during transport are also covered. Current practices related to transport of sheep during the different stages (preparation, loading and unloading, transit and journey breaks) are described. Overall, 11 welfare consequences were identified as being highly relevant for the welfare of sheep during transport based on severity, duration and frequency of occurrence: group stress, handling stress, heat stress, injuries, motion stress, predation stress, prolonged hunger, prolonged thirst, restriction of movement, resting problems and sensory overstimulation. These welfare consequences and their animal-based measures are described. A wide variety of hazards, mainly relating to inappropriate or aggressive handling of animals, structural deficiencies of vehicles and facilities, unfavourable microclimatic and environmental conditions and poor husbandry practices, leading to these welfare consequences were identified. The Opinion contains general and specific conclusions in relation to the different stages of transport. Recommendations to prevent hazards and to correct or mitigate welfare consequences have been developed. Recommendations were also developed to define quantitative thresholds for microclimatic conditions within the means of transport and spatial thresholds (minimum space allowance). The development of welfare consequences over time were assessed in relation to maximum journey time. The Opinion covers specific animal transport scenarios identified by the European Commission relating to the export of sheep by livestock vessels, export of sheep by road, roll-on-roll-off vessels and 'special health status animals', and lists welfare concerns associated with these.

How Geography and Climate Shaped the Genomic Diversity of Italian Local Cattle and Sheep Breeds

Simple Summary

In this paper, we study the inter-relationships among geography, climate, and genetics in Italian local cattle and sheep breeds. In terms of genetic diversity, geography (latitude and longitude) appears to play a larger role in sheep (26.4%) than that in cattle (13.8%). Once geography is accounted for, 10.1% of cattle genomic diversity and 13.3% of that of sheep are attributable to climatic effects. Stronger geographic effects in sheep can be related to a combination of higher predomestication genetic variability together with biological and productive specializations. The climate alone seems to have had less impact on the current genetic diversity in both species even if climate and geography are greatly confounded. Results confirm that both species are the result of complex evolutionary histories triggered by interactions between human needs and environmental conditions.

Abstract

Understanding the relationships among geography, climate, and genetics is increasingly important for animal farming and breeding. In this study, we examine these inter-relationships in the context of local cattle and sheep breeds distributed along the Italian territory. To this aim, we used redundancy analysis on genomic data from previous projects combined with geographical coordinates and corresponding climatic data. The effect of geographic factors (latitude and longitude) was more important in sheep (26.4%) than that in cattle (13.8%). Once geography had been partialled out of analysis, 10.1% of cattle genomic diversity and 13.3% of that of sheep could be ascribed to climatic effects. Stronger geographic effects in sheep can be related to a combination of higher pre-domestication genetic variability together with biological and productive specificities. Climate alone seems to have had less impact on current genetic diversity in both species, even if climate and geography are greatly confounded. Results confirm that both species are the result of complex evolutionary histories triggered by interactions between human needs and environmental conditions.