Semi-fine Wool Research Articles

Investigation of Toxoplasma gondii Infection in Yunnan Semi-fine Wool Sheep (Ovis aries) and wild Rodents in Yunnan, China.

Toxoplasma gondii, a globally distributed zoonotic obligate intracellular parasite, infects a wide array of mammals, including humans, sheep, and birds. As a unique sheep breed in southwestern China, Yunnan semi-fine wool sheep occupies an important position in animal husbandry in Zhaotong due to its strong adaptability, high reproductive rate, and excellent wool quality. Lambs infected with T. gondii are prone to neurological symptoms and growth retardation, while T. gondii infection in ewes can cause abortions, stillbirths, and deformities, thus affecting sheep reproduction and sheep product quality. Meanwhile, mutton and dairy products contaminated with T. gondii can become potential sources of human infection, potentially threatening public health and safety. To understand the T. gondii infection in semi-fine wool sheep in Zhaotong, Yunnan Province, 586 blood samples were collected and subjected to indirect hemagglutination assay (IHA) for T. gondii antibodies, and the infection-related factors were analyzed through cross-sectional analysis. In the meantime, nested PCR was conducted on a total of 217 samples collected from 31 rodents caught in and around the sheep breeding ground to test the T. gondii B1 gene in rodent tissues. A total of 94 sera tested positive for T. gondii antibodies, with a total positive rate of 16.04% (94/586) (95% CI: 14.77-20.89). Cross-sectional statistical analysis on factors related to semi-fine wool sheep infection rate, including sampling season, sex, age, and weight, suggested that age (< 6 months: 23.81%; 6-12 months: 11.74%; > 12 months: 15.83%) was a significant factor explaining the infection rate differences (P = 0.003 < 0.05, χ2 = 11.62, df = 2). Thus, age was considered a key risk factor for T. gondii infection in this study (odds ratio, OR = 2.35, 95% CI: 1.42-3.87). Nested PCR analysis on 217 (heart, liver, spleen, lung, kidney, brain, and muscle) tissues from the 31 rodents indicated that 11 tested positive. The total infection rate of rodents in and around the breeding ground was 35.48% (11/31), and 14 samples tested positive, with a positive infection rate of 6.45% (14/217). The T. gondii infection rates of semi-fine wool sheep and rodents from their breeding environment in Zhaotong, Yunnan Province, were high, necessitating enhanced prevention, control, and treatment measures to ensure the healthy breeding of semi-fine wool sheep and veterinary public health and safety.

Effects of Dietary Energy Levels on Growth Performance, Nutrient Digestibility, Rumen Barrier and Microflora in Sheep.

Dietary energy is crucial for ruminants' performance and health. To determine optimal dietary energy levels for growing sheep, we evaluated their growth performance, nutrient digestibility, rumen fermentation, barrier function, and microbiota under varying metabolic energy (ME) diets. Forty-five growing Yunnan semi-fine wool sheep, aged 10 months and weighing 30.8 ± 1.9 kg, were randomly allocated to five treatments, each receiving diets with ME levels of 8.0, 8.6, 9.2, 9.8 or 10.4 MJ/kg. The results showed that with increasing dietary energy, the average daily gain (ADG) as well as the digestibility of dry matter (DM) and organic matter (OM) increased (p < 0.05), while the feed conversion ratio (FCR) decreased linearly (p = 0.01). The concentration of total VFA (p = 0.03) and propionate (p = 0.01) in the rumen increased linearly, while rumen pH (p < 0.01) and the acetate-propionate ratio (p = 0.01) decreased linearly. Meanwhile, the protein contents of Claudin-4, Claudin-7, Occludin and ZO-1 as well as the relative mRNA expression of Claudin-4 and Occludin also increased (p < 0.05). In addition, rumen bacterial diversity decreased with the increase of dietary energy, and the relative abundance of some bacteria (like Saccharofermentans, Prevotella and Succiniclasticum) changed. In conclusion, increasing dietary energy levels enhanced growth performance, nutrient digestibility, rumen fermentation, and barrier function, and altered the rumen bacterial community distribution. The optimal dietary ME for these parameters in sheep at this growth stage was between 9.8 and 10.4 MJ/kg.

Impact of Varying Dietary Calcium Contents on the Gut Metabolomics of Yunnan Semi-Fine Wool Sheep (Ovis aries).

Yunnan semi-fine wool (YSFW) is a recently developed dual-purpose (meat and wool) sheep breed mainly found in Yunnan Province, China. Moreover, dietary calcium is essential for animal health and productivity. The current experiment aimed to investigate the impact of dietary calcium on sheep gut metabolite profile. For this, thirty YSFW rams (male, age = 10 months, and body weight = 40.37 ± 0.49 kg) were randomized into three groups (n = 10 rams/group), followed by a completely randomized design, and the groups were allotted to one of three dietary calcium levels (Q_1 = 0.50%, Q_3 = 0.73%, and Q_5 = 0.98% on a dry basis). The rams were fed ad libitum by feeding twice a day (at 08:00 and 17:00 h/day) throughout the experimental period (44 day). On the 21st day of the experiment, fecal samples were collected from 27 rams (9/group) and untargeted metabolite profiling was performed by using ultra-performance liquid chromatography. The PCA plot showed that the Q_5 group metabolites were clustered more tightly than for Q_1 and Q_3, respectively. The tightly clustering molecules were mainly alkaloids and their derivatives, benzenoids, lignans and related compounds, lipids, nucleotides, organic acids, and nitrogenous-based derivatives. According to the Kyoto Encyclopedia of Genes and Genomes pathway analysis, these molecules potentially contribute to metabolic pathways, biosynthesis of secondary metabolites, proteinaceous compounds, and the metabolism of the protein derivatives, particularly amino acids. The PLS-DA plots revealed a significant difference between the Q_1, Q_3, and Q_5 groups, suggesting that Q_5 had a clear separation across the groups. Based on the metabolomic analysis, feeding different levels of dietary calcium significantly changed the metabolomic profile of YSFW rams, which primarily entails metabolic pathways such as energy, protein, and lipid metabolism.

Are two beneficial mutations (p.Q249R and 90-bp Indel) within the ovine BMPRIB gene associated with growth traits?

The problem of achieving economic efficiency in sheep breeding can be largely solved by increasing sheep productivity. Recently, the BMPRIB gene has been revealed by GWAS as a potential candidate gene for sheep body morphometric traits. Therefore, the present study aimed to investigate whether genetic polymorphisms (p.Q249R SNP and 90-bp deletion) in the BMPRIB gene are associated with sheep growth traits. PCR-based genotyping was performed on 1,875 sheep, including 1,191 Guiqian semi-fine wool (GQSFW), 560 Luxi Blackhead (LXBH), 55 Lanzhou fat-tailed (LZFT), and 69 Weining (WN) sheep. Genotype-phenotype association was assessed using the independent samples t-test and ANOVA. The significance level was set at αoriginal < 0.05. The threshold p-value for significance was adjusted after correction for multiple comparisons using the Bonferroni correction. After the Bonferroni correction, it was found that individuals with FecB+/FecB+ genotypes of the p.Q249R had significantly better growth traits in LXBH ewe lambs, including the body length, chest width, paunch girth, cannon circumference, and hip width (P<0.0005). Meanwhile, associations were observed between 90-bp deletion polymorphism and several growth traits (body length, body height, chest depth, and canon circumference) in GQSFW ewe adults after the Bonferroni correction (P < 0.0002), and individuals with the "DD" genotypes had greater growth traits. Our findings align with the experimental observations from GWAS, which identified the BMPRIB gene as a potential candidate gene for body measurement traits. These findings not only confirm the previous study's results but also expand on them. Therefore, further investigations regarding the impact of BMPRIB polymorphisms on growth traits are necessary in other sheep breeds.

Співвідношення структурних протеїнів у вовні овець різних порід та з різною категорією волокон залежно від зон їх розведення

Wool fiber consists of a complex of protein-keratins, which differ in both their physical and chemical properties and functional characteristics. Despite the progress achieved in the study of the structural organization of fibers, the issue of the influence of environmental factors, the nature and level of nutrition, as well as breed characteristics, remains poorly understood. With this in mind, we investigated the ratio of structural proteins in the wool of sheep of different breeds, which are bred in separate zones of Ukraine, in particular, fine-wool, semi-fine-wool, and coarse-wool. Therefore, during the study of the structural proteins of the wool of sheep of different breeds, which differ among themselves in the thinness of the fibers, it was established that by the method of electrophoretic separation, these proteins are clearly divided into three different groups, in particular, these are proteins of intermediate filaments (IF) of I and II types with a molecular weight of 55–65 and 45–55 kDa, respectively, as well as keratin-associated proteins (KAP) with a molecular weight of 25–35 kDa. However, in some breeds, in particular, the Askanian meat-wool of the black-headed type and the Ukrainian Mountain Carpathian type, two more fractions of proteins were found among IF type I, which almost do not differ from each other in terms of percentage. It was established that within the studied groups of sheep, certain interbreed features are observed, so in the group of thin-wooled breeds, the largest percentage falls on IF II (35.9%). The other two factions account for almost the same percentage — 32.1% (IF I) and 31.8% (KAP). An almost similar picture of the ratio of protein fractions was recorded in the group of animals with coarse wool. At the same time, in the group of sheep with semi-fine wool, in particular, the fibers of sheep of the Ascanian meat-wool breed have the highest percentage of KAP and, accordingly, less IF II, and in the fibers of the Ascanian meat-wool black-headed type, respectively, less proteins of IF II and KAP. Therefore, the obtained data clearly indicate breed characteristics of the content and ratios of certain groups of proteins, which can be genetically determined, and therefore serve as appropriate markers both within individual breeds and within breeds with different fiber categories.

Evaluation of the Wool Production on Romanian Sheep Breeds

Abstract Sheep breeding is a traditional activity in Romania and wool production has been for a long period the main resource for the farmers’ prosperity. The opportunity of this study was generated by two main aspects: the change of the exploitation directions of sheep towards milk and meat production, which contributed to the lack of interest in selection and breeding for wool and to the reduction of the productive level and quality parameters of the wool; the absence of a national standard for classifying raw wool adapted to the current breeds structure, the conditions of sheep farming and the market requirements for this animal product An extensive study was carried out over 5 years on flocks of sheep belonging to the main local breeds Merinos de Palas, Tsigaie, Tsurcana, the newly created breeds at ICDCOC Palas Constanta respective Palas Meat Breed, Palas Milk Breed, Palas Prolific Breed as well as on some hybrids obtained through crossbreeding of new breeds with imported sheep breeds specialised for meat production (Texel and Rouge de l’ Ouest). The main goals of this study were: to establish the average level of wool production, the limits of variation and the potential for selection for wool quantity, by individual weighing of the wool fleeces harvested during the shearing season; to evaluate the wool quality level in the flocks analysed on the basis of the objective determination, by laboratory analysis on randomly collected samples, of the average fibre diameter, relative length of the staples, individual fibre length, degree of crimp, degree of impurity and the limits of variation of these quality parameters. This paper presents a summary of the values obtained for the quantity of raw wool and the fineness of wool as an essential quality parameter for the classification and valorisation of this natural resource. The results obtained in the study revealed in general a large variability in the productivity level of local sheep breeds and their hybrids with specialised imported breeds. The existence in the analysed herds of a percentage of 40-50 % of sheep performing above the flocks average (plusvariants) shows a potential for selection for the quantitative level of wool production. Thus, for these selected flocks (lines) an additional 10.23 ≈ 24.09 % wool production can be obtained compared to the averages levels. In terms of average fineness the analysis of the data shows that : the Palas Merino sheep, fall into the category of fine wool breeds; the three new sheep breeds created at ICDCOC Palas and the Tsigaie breed belonging to the Reghin - Mures Experimental Base have semi-fine wool (fiber diameter over 25 microns); the flock of White Tsurcana breed from the Bilciuresti - Dambovita Experimental Base falls into the category of sheep with semi coarse - coarse wool. The range of variation in diameter was very wide for all the breeds analysed. Thus in the Palas Merino breed differences of 5-7.5 μm between the maximum and minimum diameter measured represent according to the Bradford classification (English system) a difference of 7 fineness classes . The Tsigai breed has also a large uneveness of this parameter, CV over 20 % in rams and sheep yearlings. The analysis of the data on wool diameter revealed that more than 40% of the studied sheeps had above-average fineness, they could constitute selected flocks (lines) with higher values of the main wool quality parameter that determines the market value. Thus an increase in wool fineness of 3.63 ≈ 11.52 % can be achieved within a selected flock . The results presented showed that, under the current conditions of breeding and exploitation of sheep in the analized flocks, there is a potential of selection for wool production and for fibre diameter as the main quality parameter . Also, on the basis of the analysis carried out on the grading/classing/sorting of wool worldwide and the results obtained within this study, proposals were made to improve the quantity and increase the commercial value of wool production obtained from the sheep breeds reared in Romania.

Analysis of the Allele Fund of Semi-Fine Wool Sheep of the Pechora Population Using STR Markers

Analysis of the Allele Fund of Semi-Fine Wool Sheep of the Pechora Population Using STR Markers

Insertion/Deletion (InDel) Variants within the Sheep Fat-Deposition-Related PDGFD Gene Strongly Affect Morphological Traits.

Platelet-derived growth factor D (PDGFD) is a member of the PDGF gene family, and it plays an important role in the regulation of adipocyte development in mammals. Furthermore, genome-wide association studies (GWAS) have previously identified it as a candidate gene associated with fleece fiber variation, body size, and the fat-tail phenotype in domestic Chinese sheep. In this study, a total of 1919 indigenous Chinese sheep were genotyped to examine the association between nucleotide sequence variations in PDGFD and body morphology. Our results detected both a 14 bp insertion in intron 2 and a 13 bp deletion in intron 4 of PDGFD. Moreover, these two InDel loci had low to moderate polymorphism. Notably, the 13 bp deletion mutation of PDGFD was found to significantly affect sheep body size. Yearling rams in the Luxi black-headed sheep (LXBH) containing a heterozygous genotype (insertion/deletion, ID) were found to have larger body length, chest depth, and body weight than those with wild genotypes. Furthermore, adult ewes in the Guiqian semi-fine wool sheep (GSFW) containing a homozygous mutation (deletion/deletion, DD) were found to have smaller chest width than their peers. Moreover, yearling ewes in this group with the same homozygous mutation were found to have lower body weight, chest width, and cannon circumference compared to those of other individuals. This study demonstrates that PDGFD InDel polymorphisms have the potential to be effective molecular markers to improve morphological traits in domestic Chinese sheep.

ZOOTECHNICAL EVALUATION OF PERFORMANCE IN SEMI-FINE-FLEECED SHEEP BREEDS OF THE BELARUSIAN SELECTION

To ensure the development of sheep breeding in order to obtain high-quality competitive products it is necessary that the pedigree sheep of semi-fine fleeced breeds meet current requirements, be resistant to the specific conditions of breeding and maintenance at sheep enterprises of various forms of ownership and departmental subordination. The paper contains the materials of research aimed at refining zootechnical rules for evaluation of semi-fine wool sheep breeds of the Belarusian selection. Within the framework of studies, a comparative evaluation of the exterior and constitution development of producing sheep was carried out, data on linear and height measurements and live weight were obtained. As a result of the research, the minimum requirements for the performance of semi-fine fleeced sheep breeds of the Belarusian selection were determined and the zootechnical rules for their evaluation were refined.

ZOOTECHNICAL EVALUATION OF THE PERFORMANCE OF SEMI-FINE WOOL SHEEP BREEDS OF THE BELARUSIAN SELECTION

To ensure the development of sheep breeding in order to obtain high-quality competitive products it is neces-sary that the pedigree sheep of semi-fine wool breeds meet current requirements, be resistant to the specific condi-tions of breeding and maintenance at sheep enterprises of various forms of ownership and departmental subordina-tion. The paper contains the materials of research aimed at refining zootechnical rules for evaluation of semi-fine wool sheep breeds of the Belarusian selection. Within the framework of studies, a comparative evaluation of exterior and constitution development of producing sheep was carried out, data on linear and height measurements and live weight were obtained. As a result of the research, the minimum requirements for productivity of semi-fine wool sheep breeds of the Belarusian selection were established and the zootechnical rules for their evaluation were refined.

The ovine HIAT1 gene: mRNA expression, InDel mutations, and growth trait associations.

The hippocampal abundant transcript 1 (HIAT1) gene, also known as major facilitator superfamily domain-containing 14A (MFSD14A), encodes for a transmembrane transporter protein and has been previously shown to be associated with milk production in buffalo and sheep breeds, as well as growth traits in chicken and goats. However, tissue level distribution of the ovine HIAT1 gene, as well as its effect on body morphometric traits in sheep, has yet to be studied. The HIAT1 mRNA expression profile of Lanzhou fat-tailed (LFT) sheep was determined by quantitative real-time PCR (qPCR). A total of 1498 sheep of three indigenous Chinese sheep breeds were PCR-genotyped for polymorphisms of HIAT1 gene. Student's t-test was used to observe the association between the genotype and sheep morphometric traits. HIAT1 was widely expressed in all examined tissues, and was particularly abundant in the testis of male LFT sheep. Additionally, a 9-bp insertion mutation (rs1089950828) located within the 5'-upstream region of HIAT1 was investigated in Luxi black-headed (LXBH) sheep and Guiqian semi-fine wool (GSFW) sheep. The wildtype allele frequency 'D' was found to be more prevalent than that of the mutant allele 'I'. Furthermore, low genetic diversity was confirmed in all sampled sheep populations. Subsequent association analyses indicated an association between the 9-bp InDel mutation of interest and the morphometric traits of LXBH and GSFW sheep. Furthermore, yearling ewes with a heterozygous genotype (ID) demonstrated smaller body sizes, while yearling rams and adult ewes with the heterozygous genotype were found to have overall better growth performance. These findings imply that functional InDel polymorphism (rs1089950828) has the potential to be utilized for marker-assisted selection (MAS) of growth traits in domestic Chinese sheep populations.

Comparison of coated and uncoated trace elements on growth performance, apparent digestibility, intestinal development and microbial diversity in growing sheep.

The suitable supplement pattern affects the digestion and absorption of trace minerals by ruminants. This study aimed to compare the effects of coated and uncoated trace elements on growth performance, apparent digestibility, intestinal development and microbial diversity in growing sheep. Thirty 4-month-old male Yunnan semi-fine wool sheep were randomly assigned to three treatments (n = 10) and fed with following diets: basal diet without adding exogenous trace elements (CON), basal diet plus 400 mg/kg coated trace elements (CTE, the rumen passage rate was 65.87%) and basal diet plus an equal amount of trace elements in uncoated form (UTE). Compared with the CON group, the average daily weight gain and apparent digestibility of crude protein were higher (P < 0.05) in the CTE and UTE groups, while there was no difference between the CTE and UTE groups. The serum levels of selenium, iodine and cobalt were higher (P < 0.05) in the CTE and UTE groups than those in the CON group, the serum levels of selenium and cobalt were higher (P < 0.05) in the CTE group than those in the UTE group. Compared with the CON and UTE groups, the villus height and the ratio of villus height to crypt depth in duodenum and ileum were higher (P < 0.05) in the CTE groups. The addition of trace minerals in diet upregulated most of the relative gene expression of Ocludin, Claudin-1, Claudin-2, ZO-1, and ZO-2 in the duodenum and jejunum and metal ion transporters (FPN1 and ZNT4) in small intestine. The relative abundance of the genera Christensenellaceae R-7 group, Ruminococcus 1, Lachnospiraceae NK3A20 group, and Ruminococcaceae in ileum, and Ruminococcaceae UCG-014 and Lactobacillus in colon was higher in the CTE group that in the CON group. These results indicated that dietary trace mineral addition improved the growth performance and intestinal development, and altered the structure of intestinal bacteria in growing sheep. Compared to uncoated form, offering trace mineral elements to sheep in coated form had a higher absorption efficiency, however, had little effect on improving growth performance of growing sheep.

Short variation of the sheep PDGFD gene is correlated with litter size

Platelet-derived growth factor (PDGF) family, exert plays a key role in embryonic development, cell proliferation, cell migration, angiogenesis and reproduction. Related studies about GWAS analyses have found that PDGFD significantly affected deposition of tail fat in sheep, but there are no studies on reproduction in animals. In this study, three breed of sheep were used to find insertion/deletion (indel) fragment polymorphism of PDGFD which including Australian white (AUW) sheep (Meat type, n = 932), Guiqian semi-fine wool (GSFW) sheep (wool type, n = 60) and East Friensian milk (EFM) sheep (dairy type, n = 60). Only a 18-bp variation was polymorphic in the study AUW sheep population and the genotypes of different sheep breed are also specific. Moreover, the association analysis indicated that this variant was associated with litter size of AUW sheep in the first parity (p < 0.05). The litter size of II genotype was significantly lower than other genotypes in the first parity (p < 0.05). We also revealed that the PDGFD gene was relatively conservative in eight species, PDGFD mRNA expression in 832 sheep samples implying this gene was related to reproduction traits. Hence, these finding demonstrated the one-cause multipotency of PDGFD gene. Collectively, these results suggest that this indel can be used as an effective marker for sheep breeding.

Newly reported 90-bp deletion within the ovine BMPRIB gene: Does it widely distribute, link to the famous FecB (p.Q249R) mutation, and affect litter size?

The study of the BMPRIB gene polymorphisms has become of great importance in sheep, because it provides critical genetic tools to improve reproductive efficiency in ewes. The purposes of this study were: to assess the genetic diversity of the 90-bp deletion polymorphism within the BMPRIB gene in 52 various sheep breeds; to examine its linkage to the p.Q249R variant in the same gene, as well as to analyze its association with litter size. Herein, a total of 2313 various sheep individuals were used to detect the presence of the 90-bp deletion, among them the six breeds (Australian White (AUW), Small-Tail Han (STH), Guiqian semi-fine wool (GQSFW) sheep, etc.) were genotyped using PCR-based genotyping technology (n = 1636), and 47 breeds worldwide (including STH sheep) were genotyped via whole genome sequencing (WGS) method (n = 677). Genotyping outcomes revealed that the polymorphism was segregated in 45 of 52 breeds with varying frequencies (0.05–0.93). It is pertinent to note that the 90-bp deletion is not linked to the famous p.Q249R SNP in population of interest, except in high prolific Hu sheep. The association analysis indicated that the Del-90-bp variant showed no significant association (P > 0.05) with litter size in AUW (n = 625), GQSFW (n = 75) and STH (n = 38) ewes. Nevertheless, further investigation is needed on the importance of the Del-90-bp variant as a DNA marker that could possibly serve as an additional selection criterion in breeding ewes with high productivity.

Identification and validation of ram sperm proteins associated with cryoinjuries caused by the cryopreservation process

The change of sperm protein profile after the cryopreservation process may influence fertilization and early embryonic development. The purpose of the present study was to identify ram sperm proteomic modifications induced by the cryopreservation process using the isobaric tags for relative and absolute quantification labeling technology (iTRAQ) coupled with the parallel reaction monitoring (PRM) technology. Semen samples were collected from five Yunnan semi-fine wool rams using an electroejaculator. Sperm motility (CASA), plasma membrane (HOST test), and acrosome integrity (FITC-PSA) were evaluated after freeze-thawing. The total proteins of fresh and frozen-thawed sperm were extracted and purified, followed by identifying ram sperm proteomic modifications using the isobaric tags for relative and absolute quantification labeling technique (iTRAQ) coupled with the parallel reaction monitoring (PRM) technology. The results showed a significant reduction (P < 0.05) in all sperm parameters after thawing. 126 differentially abundant proteins (DAPs) were identified through comparison of the proteomes between fresh and frozen-thawed sperm. Among them, 90 proteins were down-regulated after the cryopreservation process. The remaining 36 proteins were up-regulated in frozen-thawed sperm. The results of functional annotation demonstrated the potential relationship of 10 DAPs with oxidoreductase activity. 18 and 15 DAPs may be involved in the stress and carbohydrate metabolic process, respectively. Furthermore, 8 DAPs may be functionally associated with reproduction. The Kyoto Encyclopedia of Genes and Genomes (KEGG) results demonstrated the primary enrichment of these identified DAPs in metabolic activities, disease, and oxidative phosphorylation. In order to confirm the reliability of the iTRAQ results, the changing trends of 10 proteins analyzed by PRM were similar to those of the corresponding proteins identified by iTRAQ. In conclusion, the cryopreservation process modifies the proteome of ram sperm, possibly leading to compromised fertility of post-thaw sperm. Additionally, the identified DAPs in this study may function as potential biomarkers for assessing the post-thaw quality of ram semen.

Sequencing Reveals Population Structure and Selection Signatures for Reproductive Traits in Yunnan Semi-Fine Wool Sheep (Ovis aries).

Yunnan semi-fine wool sheep are among the most important cultivated sheep breeds in China. However, their population structure, genetic characteristics and traits of interest are poorly studied. In this study, we systematically studied the population characteristics and selection signatures of 40 Yunnan semi-fine wool sheep using SNPs obtained from whole-genome resequencing data. A total of 1393 Gb of clean data were acquired. The mapping rate against the reference genome was 91.23% on average (86.01%–92.26%), and the average sequence depth was 9.51X. After filtering, 28,593,198 SNPs and 4,725,259 indels with high quality were obtained. The heterozygosity rate, inbreeding coefficient and effective population size of the sheep were calculated to preliminarily explore their genetic characteristics. The average heterozygosity rate was 0.264, the average inbreeding coefficient was 0.0099, and the effective population size estimated from the heterozygote excess (HE) was 242.9. Based on the Tajima’s D and integrated haplotype score (iHS) approaches, 562 windows and 11,356 core SNPs showed selection signatures in the Yunnan semi-fine wool sheep population. After genome annotation and gene enrichment analysis, we found traces of early domestication in sensory organs, behavioural activity and the nervous system as well as adaptive changes in reproductive and wool traits under selection in this population. Some selected genes related to litter size, including FSHR, BMPR1B and OXT, were identified as being under selection. Specific missense mutations of the FSHR gene that differed from the reference genome were also identified in the population, and we found some SNP variations that may affect litter size. Our findings provide a theoretical basis for the conservation and utilization of Yunnan semi-fine wool sheep. Furthermore, our results reveal some changes common to sheep after domestication and provide a new opportunity to investigate the genetic variation influencing fecundity within a population evolving under artificial selection.

Using sheep selection to improve the nutritional value of lambmeat

Relevance. The article provides a justification for the use of sheep selection taking into account the intra-breed type of Prekos ewes in purebred breeding and crossing with producers of semi-fine wool breeds Romney-Marsh and Kuibyshevskaya to improve the biological usefulness of meat in offspring.Methods: scientific and economic experiment in the use of different selection options, taking into account the productive type of sheep of the Precos breed.Results. The article presents the results of a study on the influence of the selection of sheep on the composition of lambmeat, increasing the usefulness and quality of meat and, thus, the efficiency of its production. It was found that the content of water in the meat of crossbred animalswas lower compared to purebred Precos. There is a lower water content in the meat of rams obtained from sheep of the Precos meat-wool type, both in purebred and crossbred animals. In terms of the protein content in meat, there is an advantage in rams with purebred breeding and crossing compared to meat obtained from the wool-meat type of queens. In the hip bran of purebred animals and crossbreeds with the Kuibyshev breed, this superiority was 1.1% (Р &gt; 0.95), and in the lumbar bran of Romney-Marsh crossbreeds, this difference was 1.6% (Р &gt; 0.95). Mutton from the offspring of the sheep of meat-wool type is characterized by a significantly high content of the essential amino acids threanine, lysine, leucine, phenylanin and isoleucine in comparison with meat from the offspring of the wool-meat type of sheep. A significant superiority was also established in the content of interchangeable amino acids — oxyproline, serine, tyrosine, proline, glycine, aspartic and glutamic acid, cystine and analin.

Analysis of external features and live weight of woolly-meaty sheep (ovis aries)

This article addressed the development and the growth of offspring, the external characteristics and the productivity at different breeding periods of woolly-meaty sheep of Uzbekistan. It was observed that wool productivity was higher in sheep rich in wool-meat than ordinary sheep; sheared wool was 1.26 kg (49.6%), after washing it was 0.97 kg (67.8%), wool length was 2.13 (19.2%) higher. Live weights of lambs from ewes in the experimental groups were determined at birth, at 30 days of age, and 3 months of age. From September 1 to September 20 of the year, the live weight, body size and wool productivity of early inseminated ewes were higher than those of inseminated ewes from late October to November 10. The live weight of lambs obtained from artificially inseminated sheep with frozen semen of typical rams in world gene pool considered semi-fine wool in the meat-wool direction was higher than sheep naturally inseminated with pedigree rams. Accordingly, it was heavier by 00.4 kg (9.3%) at the first day of birth, followed by 0.5 kg (6.8%) at 10 days, and 0.4 kg (1.3%) at 3 months of age.

СОВЕРШЕНСТВОВАНИЕ ПРОДУКТИВНЫХ КАЧЕСТВ КАЗАХСКИХ МЯСОШЕРСТНЫХ ПОЛУТОНКОРУННЫХ ОВЕЦ ПУТЕМ ИСПОЛЬЗОВАНИЯ ПОРОДЫ РОМНИ-МАРШ

The article presents the wool productivity of different sex and age groups of Kazakh meat-wool semi-fine wool sheep in the south and south-east of Kazakhstan. The growth and development, meat and woolen productivity, meat and breeding qualities of purebred and kneaded lambs and yaks of the first generation of kneaded Kazakh meat-wool semi-fine sheep with the blood of Romney marsh breed have been studied.

Hepatic Injury Induced by Dietary Energy Level via Lipid Accumulation and Changed Metabolites in Growing Semi-Fine Wool Sheep.

Liver injury threatens the overall health of an organism, as it is the core organ of the animal body. Liver metabolism is affected by numerous factors, with dietary energy level being a crucial one. Therefore, the present study aimed to evaluate hepatic injury and to describe its metabolic mechanism in ruminants fed diets with different dietary energy levels. A total of 25 Yunnan semi-fine wool sheep were fed diets with five dietary metabolic energy levels and were randomly assigned to five groups as follows: low energy (LE), medium–low energy (MLE), medium energy (ME), medium–high energy (MHE), and high energy (HE). The results revealed that the average optical density (AOD) of lipid droplets in the LE, MLE, and HE groups was higher than that in the ME and MHE groups. The enzyme activity of alanine aminotransferase (ALT) was the lowest in the ME group. An increase in dietary energy level promoted the superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity and altered the malondialdehyde (MDA) and protein carbonyl (PCO) concentration quadratically. In addition, both high and low dietary energy levels upregulated the mRNA abundance of proinflammatory cytokine interleukin (IL)-1β, nuclear factor-kappa B (NF-κB), and tumor necrosis factor (TNF)-α. Metabonomic analysis revealed that 142, 77, 65, and 108 differential metabolites were detected in the LE, MLE, MHE, and HE groups, compared with ME group respectively. These metabolites were involved in various biochemical pathways, such as glycolipid, bile acid, and lipid metabolism. In conclusion, both high and low dietary energy levels caused hepatic injury. Section staining and metabonomic results revealed that hepatic injury might be caused by altered metabolism and lipid accumulation induced by lipid mobilization.