Sheep Breeds Research Articles

BbGSD: Black-boned Sheep Genome SNP Database.

Lanping black-boned (LPBB) sheep are a unique and rare ruminant species, characterized by black pigmentation in the skin and internal organs. Thus far, LPBB are the only known animal with heritable melanin characteristics besides the black-boned chicken, and the only mammal known to contain a large amount of melanin in the body. LPBB have therefore attracted substantial research attention, due to their potential contribution to medicine. However, long periods of grazing freely and crossbreeding with Lanping normal sheep (LPN) have diluted LPBB breeding resources, posing a challenge to the protection of species. To ensure the effective conservation and management of LPBB genetic resources, the construction of a large-scale database of genotypic information is therefore very important. To achieve this, we established the first LPBB-specific SNP database, named Black-boned Sheep Genome SNP Database (BbGSD, http://202.203.179.115:3838/oarsnpdb) using sheep genotype data (100 LPBB and 50 LPN) across 46 894 242 SNP sites. In this database, we implemented four main function modules: (i) the "LD heatmap" module, which uses a heatmap to enable the interactive visualization of pairwise linkage disequilibrium (LD) measurements between SNPs; (ii) the "SNP distribution" module, which allows users to interactively visualize tabular genotype data as heat maps; (iii) the "Phylogenetics" module which enables phylogenetic analysis to explore the evolutionary history or genetic relationships of the LPBB sheep; and the "Diversity" module, which can be used to calculate and display the nucleotide diversity among sheep populations in user-specified genomic regions. BbGSD is essential for accelerating studies on the functional genomics and screening of molecular markers of molecular-assisted breeding in black-boned sheep. Database URL: http://202.203.179.115:3838/oarsnpdb.

Mixing groups of sheep changes vocalizations when an individual animal is isolated

In recent years, welfare, which includes pleasurable and unpleasant emotions, is of utmost importance in animals reared under intensive farming systems. Various indices have been reported to evaluate welfare. Among them, vocalizations form non-invasive indices of animals’ inner state. The aim of the study was to determine whether changes in ewes’ raising group composition may alter differences in their vocal characteristics. Forty animals of two dairy sheep breeds (Chios and Karagouniki) were used. The experiment lasted for six months divided into three equal periods (A, B, and C). During period A, the animals were divided in two groups based on their breed. In period B the animals were equally mixed in two groups, while in period C the animals returned to their initial state, as in period A. The behaviour of the ewes was recorded during the entire experimental period. At the end of each period, each ewe was isolated, and its vocalizations and behaviour recorded. The composition of the group influenced (p < 0.05) the basic parameters related to frequency and amplitude, which indicates a negative emotional valence. This negative effect was also supported by the behavioural observations. Breed influenced parameters related to the bleat duration, fundamental frequency disturbance (i.e., shivering, shimmering) and behavioural indices including success index during an agonistic intersection and proportion of related affiliative behaviours. The study showed that changes in group composition can affect the emotional state of animals providing information for better handling practices with regard to improving welfare.

ЗОНАЛЬНАЯ СПЕЦИАЛИЗАЦИЯ ЖИВОТНОВОДСТВА РЕСПУБЛИКИ ТЫВА

For agriculture of the Republic of Tuva, animal husbandry has always been the leading industry, which is facilitated by the natural and climatic conditions of the region. The territory of the republic is divided into 4 agricultural zones according to the geographical location, taking into account climatic features, terrain, soil cover, vegetation. The purpose of research was to analyze the current state and prospects for the development of the animal husbandry industry of the Republic of Tuva in the context of natural and climatic agricultural zones. It was determined that the largest number of cattle and horses is currently concentrated in the central zone (42.1 and 42.0 %), followed by the western (35.0 and 31.3 %) and southern (19.5 and 24.4 %) zone. About half of the total number of small cattle (45.3 %) is kept in the southern zone, in the central and western zones – 27.6 and 26.6 %, respectively. For the central zone, which has the largest arable land and large areas of steppe, forest-steppe, foothill, mountain pastures, it is effective to develop dairy and beef cattle breeding, early maturing meat and wool, semi-coarse and fine-wool sheep breeding, wool goat breeding, and horse breeding. In the western zone, characterized by a more severe climate, about half of the pastures of the republic are located, which creates conditions for breeding dairy and beef cattle, semi-coarse and coarse-wooled sheep, woolly goats, horses, yaks in some areas of the zone. The southern zone of dry steppes is optimal for breeding beef cattle, coarse-wooled and semi-coarse-wooled sheep, goats, both woolly and coarse-haired horses. The main branch of animal husbandry in the eastern mountain-taiga zone is reindeer breeding.

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 [...]

Carbohydrate and mineral metabolism in romanov sheep in Western Siberia

The article presents information regarding the metabolism of carbohydrates and minerals in Romanov sheep in the Kemerovo region. The correlations among macro elements and carbohydrate metabolism indices and heavy metal levels in organs and tissues were ascertained. We determined the average content, variability and reference intervals of glucose, amylase, lactate dehydrogenase and macro elements in blood serum. We investigated the relationship between these indices and heavy metal levels in sheep organs and tissues. In the Romanov sheep breeding zone, heavy metal content was analyzed in soil, water, and feed and did not exceed the MAC. The determination of the content of macroand microelements was carried out in the laboratory of isotopegeochemical methods of analysis at the V.S. Sobolev Institute of Geology and Mineralogy of the Siberian Branch of the Russian Academy of Sciences by atomic emission spectrometry employing the NSAM analysis technique No. 450-S. The level of blood serum glucose is 6.0 mmol/l, the amylase is 104.0 U/l, and the lactate dehydrogenase is 1086 U/l. The order of macro elements in serum is as follows: Na &gt; K &gt; Ca &gt; P &gt; Mg in accordance with 90 : 7 : 4 : 3.4 : 1. The concentration of K in the blood exhibits a significant correlation with Zn in the spleen (r = 0.507) and Cu in the testes (r = 0.535). Simultaneously, Na exhibited a negative correlation with the concentration of Zn in the heart (r = -0.416) and Pb in the blood (r = −0.598). There was a high negative relationship between Ca in the blood and the frequency of chromosomal breaks (r = −0.752). The glucose level was negatively correlated with the concentration of Cu in the muscles (r = −0.414), Zn in the kidneys (r = −0.465), and Zn in the heart (r = −0.572), but its level was positively associated with Pb in the muscles (r = 0.568). The significance of the indicators of carbohydrate and mineral metabolism, as well as the correlations between the studied parameters, is evident in the comprehensive evaluation of the breeds phenopool.

Key Performance Indicators as Predictors of Enterprise Gross Margin in English and Welsh Suckler Beef and Sheep Farms

A large proportion of the lowest annual farm profits in the United Kingdom in recent years comes from lowland and Less Favoured Area (LFA) beef and sheep farms. Benchmarking the performance of a business through routine data collection can provide the information needed to make changes to enterprise management and performance. Key performance indicators (KPIs) are globally recognised measures that can provide farmers with this capability. However, it is largely unknown if there are specific KPIs relating to livestock production that have a significant effect on financial performance. The aim of this study was to determine whether KPIs could be used as predictors of financial performance (gross margin, GM), on suckler beef and sheep farms in England and Wales. This was completed using data from the Farm Business Survey (FBS), which is the largest stratified financial survey of its kind in the UK. Following data extraction, multiple linear regression models were developed for four enterprise types: LFA suckler beef, lowland suckler beef, LFA ewe and lowland ewe. Several KPIs were significantly associated with gross margin per head in all enterprise types. KPIs that were positively associated with GM were measures of livestock productivity, which were lambs per breeding stock and calves per cow. The increased expenditure on concentrate feed had a significantly negative association within all enterprise types, except for LFA suckler beef enterprises, where cow mortality had the greatest significantly negative association. This is the first study to demonstrate the influence livestock production KPIs have on the financial performance of suckler beef and sheep enterprises in both England and Wales, highlighting the importance of routine data collection and benchmarking.

No rumen fermentation profiles and associated microbial diversities difference were found between Hu sheep and Karakul sheep fed a cottonseed hull diet

BackgroundThis research aimed to investigate differences in rumen fermentation characteristics between Karakul sheep and Hu sheep reared under identical conditions. The test subjects included newborn Hu and Karakul sheep, which were monitored across three stages: stage I (Weaning period: 15 ~ 30 days), stage II (Supplementary feeding period: 31 ~ 90 days), and stage III (Complete feeding period: 91 ~ 150 days). During the supplementary feeding period, cottonseed hulls were the main roughage source. To analyze the dynamics of rumen fermentation, 16S rRNA sequencing and metabolomics methods were employed, alongside measurements of rumen fermentation parameters and cellulase activity. This comprehensive approach aimed to investigate the potential impact of breed on rumen fermentation indicators, microbial community structure, and metabolites in Hu and Karakul sheep.ResultsThe 16S rRNA sequencing analysis revealed no significant differences in the relative abundance or dominant bacterial communities in the rumen across all stages. In stage II, rumen bacteria in both Hu and Karakul sheep were relatively stable. However, the Simpson index of Hu sheep in stage II was substantially greater than that of Karakul sheep, demonstrating similarities in the rumen microbial structure between stages II and III. Dynamic variations in fermentation parameters and cellulase activity in the rumen revealed that the indicators in both sheep breeds stabilized at 150 days. Metabolomic results revealed that the metabolic pathways in stage I were mainly concentrated in purine metabolism and lipid metabolism, while stage II was dominated by amino acid metabolism. Stage III involved mainly in pyrimidine and purine metabolism. An exploration of the relationships among rumen microbial biomarkers, key differentially abundant metabolites and rumen characteristics indicated that Karakul sheep exhibited superior lipid metabolism compared to Hu sheep.ConclusionThese findings reveal that there were no interbreed differences in the rumen characteristics of Hu and Karakul sheep when fed the same cottonseed hull diet, despite differences in their metabolic pathways. The findings also indicate that the first 20 days represent the initial stage of rumen bacteria in Hu sheep, followed by a transition phase between 20 and 90 days, and a relatively stable stage from 90 to 150 days. These results provide a scientific basis for further understanding the rumen function of sheep and for optimizing their feeding strategies.D2CHRS7zryw_AWg9hJmKX2Video

The accumulation of harmful genes within the ROH hotspot regions of the Tibetan sheep genome does not lead to genetic load

BackgroundProlonged natural selection and artificial breeding have contributed to increased uniformity within the Tibetan sheep population, resulting in a reduction in genetic diversity and the establishment of selective signatures in the genome. This process has led to a loss of heterozygosity in specific genomic regions and the formation of Runs of Homozygosity (ROH). Current research on ROH predominantly focuses on inbreeding and the signals of selection; however, there is a paucity of investigation into the genetic load and selective pressures associated with ROH, both within these regions and beyond. On one hand, genes located situated ROH hotspot regions exhibit a degree of conservation in their genomic segments; on the other hand, these regions may also serve as critical loci for identifying signals of selection.ResultsHigh-throughput re-sequencing technology was utilized to investigate the ROH hotspot regions across 11 Tibetan sheep populations, resulting in the identification of ten conserved genes (ARHGEF16, Tom1l2, PRDM16, PEMT, SREBF1, Rasd1, Nt5m, MED9, FLCN, RAI1) that are associated with lipid metabolism, lactation, and development. These genes exhibited highly conserved within the ROH hotspot regions across all Tibetan sheep populations. Employing the integrated haplotype score (iHS) method, we screened for selective sites within frequently observed ROH hotspot regions to elucidate genomic differences among Tibetan sheep populations. A comprehensive analysis was conducted, involving Rnhom, dN/dS ratios, missense/synonymous ratios, and loss-of-function (LOF)/synonymous ratios, to investigate the accumulation of deleterious genes and the associated genetic load both within and outside ROH hotspot regions. The results revealed a higher accumulation of deleterious genes and a reduced genetic load within the ROH regions.ConclusionsThis study provides a comprehensive and precise genomic analysis and interpretation of Tibetan sheep, offering theoretical basis for genetic breeding and evolution in Tibetan sheep.

Microbiological Quality and Safety of Raw Sheep Milks from Native Epirus Breeds: Selective Effects of Thermization on the Microbiota Surviving in Resultant Thermized Milks Intended for Traditional Greek Hard Cheese Production

Thermization is a sub-pasteurization heat treatment widely applied in traditional Greek hard cheese technologies. In this study, five bulk milk batches from two native Epirus sheep breeds were analyzed microbiologically before (raw milk; RM) and after thermization at 65 °C for 30 s (TM) followed by characterization of 125 presumptive LAB isolates from each of the counterpart RM and TM samples. PsychrotrophicPseudomonas-like spoilage bacteria and mesophilic LAB, primarily of the genera Leuconostoc (48.4%) and Lactococcus/Streptococcus (32.8%), co-dominated in RM at mean levels 5.7–6.3 log CFU/mL, whereas thermophilic LAB, Enterococcus, Staphylococcus, coliforms, and yeasts were subdominant at mean levels 4.1 to 5.2 log CFU/mL. Coagulase-positive staphylococci were abundant (3–4 log CFU/mL) in all RM batches. Listeria monocytogenes was found in one batch. Both pathogens were diminished by thermization, which reduced all non-LAB contaminants below 100 CFU/mL. Enterococci (68.6%) were highly selected in all TM batches, followed by thermophilic streptococci (8.6%). Only 7.4% of the total RM microbiota survived in the resultant five TM batches. Leuconostoc showed the lowest (1.3%) survival. Thus, thermization improved the quality and safety of raw sheep milk, but reduced mesophilic LAB by ca. 2 log units in favor of enterococci in TM.

Generation and propagation of high fecundity gene edited fine wool sheep by CRISPR/Cas9

CRISPR/Cas9 technology has been widely utilized to enhance productive performance, increase disease resistance and generate medical models in livestock. The FecB allele in sheep is a mutation in the BMPRIB gene, recognized as the first major gene responsible for the high fecundity trait in sheep, leading to an increased ovulation rate in ewe. In this study, we employed CRISPR/Cas9-mediated homologous-directed repair (HDR) to introduce a defined point mutation (c.746 A > G) using single-stranded oligonucleotides (ssODN) and the ligase IV inhibitor (SCR7) into the BMPRIB gene of fine wool sheep. A total of nine gene-edited sheep were produced, six of which carried the targeted point mutation, with a precise base substitution efficiency (A > G) of 31.6%. Based on the six targeted founders (F0), we expanded the BMPRIB-targeted population, which included F1 heterozygous (B+) and F2 homozygous(BB) or heterozygous offspring. The average litter size of F1 ewes carrying the B + allele reached 170%, comparable to that of heterozygous native Australian Booroola sheep. Gene-edited ewes with B + and BB genotype produced 0.62 and 0.42 more lambs, respectively, compared to wide-type ewes (p < 0.01). Our results also indicated that the parity signification, our data demonstrate that highly efficient introduction of the intended base mutation into the sheep genome can be achieved by combining the CRISPR/Cas9 system with ssODN and SCR7. The offspring of BMPR/B edited sheep with the defined mutation exhibited high fecundity performance. Compared to conventional sheep breeding strategies, genetic improvement through gene editing offered significant advantages without compromising the fine wool traits of Merino sheep, which are often affected by routine cross-breeding methods.

Impact of Mating Methods and Semen Preservation on Reproductive and Growth Performances in Palestinian Assaf Sheep.

As global demand for sheep products increases, improving reproductive efficiency and lamb growth performance has become a priority for sheep farmers. Artificial insemination (AI) offers several advantages over natural mating, including improved genetic selection and disease control. This study contributes to understanding the impact of different mating methods and semen preservation techniques on reproductive performance and growth traits in Palestinian Assaf sheep under local breeding conditions. The research included 123 adult Assaf ewes from two farms, which were hormonally synchronized and divided into three groups for different reproductive biotechnologies. Group 1 (G1) comprised 50 ewes inseminated with frozen semen straws, while Group 2 (G2) had 37 ewes inseminated with fresh semen from genetically superior rams. Both G1 and G2 used 0.5 mL straws containing 250 million sperm, with insemination occurring 48 h post sponge removal and eCG hormone injection. Group 3 (G3) consisted of 36 ewes that underwent natural mating at a ratio of 1 ram to 6 ewes. The study revealed that insemination methods significantly affected fertility rates (45.4, 61.1, and 71.9% for G1, G2, and G3, respectively; p < 0.05). Artificial insemination notably enhanced lamb performance indicators (p < 0.05), although it did not significantly influence prolific lambing (p > 0.05). Prolific lambing significantly impacted birth weight, weaning weight, and average daily gain at 60 days across all groups (p < 0.05), but not the average daily gain or final weight at 180 days (p > 0.05). The management system significantly affected birth and weaning weights at 60 days (p < 0.05), but not the final weight at 180 days or prolific lambing (p > 0.05). Lamb sex significantly influenced average daily gains at 60 and 180 days, as well as final weight at 180 days (p < 0.05). The findings suggest that, while artificial insemination with semen from elite rams may reduce fertility rates, it significantly improves lamb performance rates. In conclusion, our study demonstrates that, while natural mating offers higher fertility rates, AI with fresh semen can be a valuable tool for improving lamb growth performance in Palestinian Assaf sheep. These findings provide valuable insights for sheep farmers in the region to optimize reproductive strategies and enhance lamb production.

Haematobiochemical alterations and lesion characterization induced by haemonchosis in slaughtered sheep at Gondar ELFORA abattoir, Ethiopia

Haemonchosis is a major gastrointestinal parasitic infection in sheep caused by H. contortus. An abattoir-based cross-sectional study was conducted from January to September 2024 to assess the haematobiochemical alterations and lesion characterization induced by haemonchosis in slaughtered sheep at Gondar ELFORA abattoir. The study involved 60 male local breed sheep, divided into 30 infected and 30 non-infected controls. The selection process involved postmortem examination of the abomasum tissues, incision, palpation, and visual inspection. Blood samples were taken for haematology and serum biochemical profiles, and a three cm tissue sample with typical H. contortus lesions was also taken. The study found significant reductions in hemoglobin, hematocrit, corpuscular volume, hemoglobin, and red blood cell counts in the infected group compared to the non-infected group. However, white blood cells, monocytes, neutrophils, and eosinophils were significantly higher in the infected group. Biochemical parameters showed significant reductions in total protein, albumin, globulin, and albumin-to-globulin ratio in the infected group. Erythrocyte indices indicated microcytic normochromic anemia. Gross examination revealed hemorrhages, dark brown abomasal contents, blood streaks, and a nodular lesion. Microscopic analysis revealed tissue-dwelling worms, submucosal hemorrhage, mucosal gland hyperplasia, thickened muscularis, and hyperplastic abomasal glands. The alterations in haematobiochemical parameters support the findings from gross and microscopic lesions. Thus, integrating haematobiochemical analysis with gross and microscopic lesion characterization improves the diagnosis of haemonchosis. Due to hypoproteinemia observed, it is advisable to supplement helminth-infected animals with protein-rich feeds, such as legumes.

Effect of FABP4 Gene Polymorphisms on Fatty Acid Composition, Chemical Composition, and Carcass Traits in Sonid Sheep.

Fatty acids (FAs) are a group of organic compounds that are regulated by polygenic and environmental factors and affect the taste, nutritional value, and quality of meat. Lamb meat is rich in FAs required by the human body, which has directed more attention to sheep research and meat production. The fatty acid-binding protein 4 (FABP4) gene is considered a candidate gene that can affect FA composition in livestock. Therefore, the aim of this study was to screen for genetic polymorphisms of FABP4 and confirm the association between these polymorphisms and FAs, chemical composition, and carcass traits in Sonid lambs. The results of the association study showed that g.57764667T>C, g.57764436T>G, g.57764242G>A, and g.57757988A>G were associated with the composition of certain long-chain FAs, and g.57764242G>A, g.57764436T>G, and g.57758026G>A were associated with free amino acid levels. In addition, g.57764667T>C and g.57757988A>G were associated with carcass weight and live weight in Sonid lambs. Therefore, the polymorphisms of the FABP4 gene are expected to be a genetic selection marker for superior traits in Sonid sheep breeding, which also provides new insights into how the ovine FABP4 gene affects traits of lamb quality.

Morphological and Molecular Identification of Obligatory Myiasis-Causing Species in Wild Cervids in Croatia.

The infestation of ruminants by fly larvae of the Oestridae family can lead to nasopharyngeal or subcutaneous myiasis, which can harm animal welfare and productivity on sheep and cattle farms. The infestation of wild ruminants allows them to serve as reservoirs for subsequent transfer to domestic animals. The fly species most commonly responsible for myiasis have been well studied in many parts of the world, but less so in southeastern Europe. Here, we identified three botfly species among 197 subcutaneous larvae and 138 nasopharyngeal larvae from 36 wild roe deer (Capreolus capreolus) and 9 wild red deer (Cervus elaphus) at 30 locations across Croatia. Instars were stored in 75% ethanol and their species and developmental stage were identified based on morphological and morphometric keys. Subcutaneous larvae in both cervid species were identified as Hypoderma diana, while nasopharyngeal larvae were identified as Cephenemyia simulator in roe deer and Pharyngomyia picta in red deer. Partial sequencing of the gene-encoding mitochondrial cytochrome oxidase subunit I confirmed the taxonomic classification of C. stimulator and P. picta but was unable to confirm that of H. diana for lack of previously published sequences. This study appears to be the first to combine the morphological and molecular characterization of myiasis-causing botflies in wild cervids in southeastern Europe.

Sustainability Indicators of Different Production Systems of a Greek Local Sheep Breed

This study develops a toolkit of sustainability indicators to analyze the economic, environmental, and social performance of various pasture-based production systems rearing Karagkouniko sheep (both specialized and mixed), and compares it with the intensive Lacaune production system in the same region. The analysis showed that despite the lower milk productivity, the group of specialized livestock Karagkouniko farms was more profitable compared to the Lacaune (35% higher net profit) production system, mainly due to savings in purchased feedstuff (64% lower expenses). This implies that grazing—if properly managed—can indeed enhance the profitability of farms. The group of mixed Karagkouniko farms—cultivating crops for both feedstuff and markets—was the least profitable group (−144.76 per ewe) as well as the least efficient in terms of use of energy (EUR 4.66 of output per EUR 1 of energy cost) and agrochemical inputs (537.2 kg of fertilizers and 3.3 liters of pesticides per ha). This suggests that strong organizational skills are required to effectively manage both crop and livestock production. Trade-offs were also observed between the sustainability dimensions. To address these trade-offs and ensure a transition to more sustainable agriculture, a comprehensive framework should be developed, integrating a mix of socioeconomic and agro-environmental schemes.

Assessment of the relationship between body weight and body measurements among Morkaraman, Tushin and Awassi sheeps with different ages

This study aimed to identify morphological predictors of body weight in Morkaraman, Tushin, and Awassi sheep across different age groups, providing valuable insights for effective livestock management and breeding programs. Data were collected from 260 Morkaraman, 109 Tushin, and 96 Awassi sheep, with body measurements including body length (BL), wither height (WH), chest girth (CG), chest width (CW), chest depth (CD), rump width (RW), rump height (RH), ear length (EL), head length (HL), forehead width (FW), cannon forelimb circumference (CFC), and cannon hindlimb circumference (CHC). Pearson correlation analysis was conducted to assess relationships between body weight and these morphological traits. A multiple linear regression model was developed using the backward stepwise elimination method to estimate body weight based on the collected measurements. The results revealed that the Morkaraman breed and the 3-year-old age group had the highest average body weights. Among the morphological traits, CG (r = 0.702), RH (r = 0.694), BL (r = 0.678), and WH (r = 0.677) exhibited the strongest correlations with body weight. The final regression model identified CG, RW, RH, and HL as the most significant predictors, collectively explaining approximately 78.3% of the variation in body weight. These findings underscore the importance of selecting specific morphological traits for accurate body weight estimation in sheep. The results of this study have significant implications for sheep farming, particularly in enhancing breeding, management, and selection strategies. By focusing on key morphological predictors, livestock producers can improve decision-making processes, optimize resource allocation, and promote the overall productivity and sustainability of sheep farming operations.

Heat Tolerance Differences Between Hu Sheep and Hu Crossbred Sheep in Microbial Community Structure and Metabolism.

The frequent occurrence of extreme temperature events causes significant economic losses to the livestock industry. Therefore, delving into the differences in the physiological and molecular mechanisms of heat stress across different sheep breeds is crucial for developing effective management and breeding strategies. This study explores the differences in heat tolerance mechanisms between Hu sheep and Xinggao sheep by comparing their growth performance under normal and heat stress conditions, as well as examining the differences in physiological, biochemical, and antioxidant indicators related to heat tolerance, serum metabolomics, and gut microbiomics in a heat stress environment. The results indicate that with changes in the temperature-humidity index (THI), Hu sheep exhibit superior stability in respiratory rate (RR) and rectal temperature (RT) fluctuations compared to Xinggao sheep. In terms of biochemical indicators and antioxidant capacity, the levels of creatinine (Cr) and superoxide dismutase (SOD) in Hu sheep serum are significantly higher than those in Xinggao sheep. In comparison, alkaline phosphatase (ALP) and malondialdehyde (MDA) levels are significantly lower. Metabolomic results showed that, compared to Hu sheep, Xinggao sheep exhibited higher cortisol (COR) and dopamine (DA) levels under heat stress conditions, a stronger lipid mobilization capacity, and elevated levels of tricarboxylic acid (TCA) cycle-related metabolites. Furthermore, gut microbiome analysis results indicate that Hu sheep demonstrate stronger cellulose degradation capabilities, as evidenced by significantly higher abundances of microorganisms such as Ruminococcus, Fibrobacter, and Bacteroidales_RF16_group, compared to Xinggao sheep. In summary, Hu sheep exhibit stronger heat tolerance compared to Xinggao sheep. These findings provide an important theoretical basis for the breeding and selection of heat-tolerant meat sheep varieties and offer strong support for the region's livestock industry in addressing the challenges posed by global warming.

Detection of Insertion/Deletions (InDel) Within Five Clock Genes and Their Associations with Growth Traits in Four Chinese Sheep Breeds.

Organisms have the capacity to detect day-night fluctuations through oscillators regulated by circadian clock genes, which are crucial for regulating various biological processes. Numerous studies have demonstrated a marked association between these genes and various growth traits of sheep. This study identified polymorphisms at 23 potential loci within five clock genes in four Chinese sheep breeds. Only two polymorphic insertion/deletions (InDels) were detected in CLOCK and PER3 genes, respectively. The distribution of these two loci in four Chinese sheep breeds and their association with growth traits were further explored. A 12 bp deletion was found in the intron of the CLOCK gene (rs604230640), which was significantly associated with body height (p < 0.05), body oblique length (p < 0.05) and cannon girth (p < 0.05) in Hu sheep (HS). A 22 bp insertion in the intron of the PER3 gene (rs600537720) with a dominant genotype of insertion/insertion (II) was found to have a significant association with chest depth (p < 0.05) in Small-Tail Han sheep (STHS), tail width (p < 0.05) in Tong Sheep (TS), and in Lanzhou fat-tailed sheep (LFTS). In conclusion, this study has elucidated the polymorphisms of CLOCK and PER3 genes and has examined the influence of these two genes on the growth traits of sheep. Concurrently, the two molecular markers identified in CLOCK and PER3 could potentially serve in the marker-assisted selection of growing-related traits in local Chinese sheep breeds.

Genome-wide discovery of underlying genetic factors associated with fresh and frozen-thawed semen traits in composite ram breeds exhibiting different cryotolerance.

Fewer studies investigate the effects of underlying genetic factors related to semen characteristics, significantly affecting sheep farm profitability. This study aimed to identify single nucleotide polymorphisms (SNP) and genomic regions associated with fresh and frozen-thawed semen traits in rams with low (Hasak) and high (Hasmer) cryotolerance. Semen collected from 11 (5 Hasak with low and 6 Hasmer with high cryotolerance) rams cryopreserved in 0.25 ml straws in the breeding season. Quality characteristics were determined in fresh, equilibrated, and frozen-thawed semen. A Genome-Wide Association Study (GWAS) was conducted to unveil the genetic structure that might be attributed to cryotolerance in low and high cryotoleranced rams. Fresh (regarding total and progressive motility) and equilibrated semen quality were similar in Hasak and Hasmer rams (p > 0.6). However, the freeze-thawing process had a more pronounced negative effect on ram semen traits in Hasak than in Hasmer (p < 0.05). GWAS revealed 27 SNPs correlated with post-thaw semen parameters. Moreover, network analyses revealed pathways related to sperm ion channels and their activities, providing insights into the intricate molecular mechanisms underlying sperm physiology and emphasizing their role in potentially impacting sperm cryotolerance. The functional significance of detected SNPs and the associated pathways require further exploration.

Using Microalgae as a Good Motivator of Ossimi Lamb's Health and Growth

ABSTRACTIn tropical and subtropical countries like Egypt, sheep breeding faces environmental thermal stress, especially during the summer when air temperature and humidity are very high. Using Microalgae as an alternative feedstuff can significantly improve sheep growth, health and oxidative status. Therefore, this study aimed to evaluate the effect of consuming two different species of microalgae: Spirulina platensis (SP) and Chlorella vulgaris (C. vulgaris) on the following: growth performance, oxidative status, kidney and liver function, serum Glu, proteins and lipids profile and haematological parameters under hot dry environmental conditions. A total of 32 Ossimi male lambs were divided randomly into four equal groups (n = 8), (G1) was fed the control diet, (G2) was supplemented with S. platensis, (G3) was supplemented with a combination between (S. platensis and C. vulgaris) and (G4) was supplemented C. vulgaris. The results of our study revealed that microalgae supplementation significantly (p ≤ 0.05) enhanced lamb's growth, liver and kidney function, levels of serum immunoglobulin IgG, glutathione peroxidase (GPX) and haematological parameters. Moreover, the levels of thyroid hormones and serum proteins profile were significantly increased in all treated lambs compared to the control group. Our research revealed that including microalgae in sheep's feed can enhance their immune system, promote growth and enhance their general health by mitigating the harmful effects of heat and oxidative stress.