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Background/Objectives: Orenburg goats are renowned for their soft down that acts as a substrate for warm clothing, particularly shawls that have an international reputation. As with many local livestock breeds, however, the Orenburg is presently at risk of extinction, an issue that can be addressed by assessing population genetic diversity and, thereafter, encouraging as much outbreeding as possible. Using single-nucleotide polymorphism (SNP)-based data, therefore, we analyzed the genetic diversity and population structure of modern Orenburg goats using samples collected from an expedition to Orenburg Oblast in 2024. Methods: We applied the Goat SNP50 BeadChip (Illumina, San Diego, CA, USA) for the genotyping of Orenburg goats from modern and archived populations. SNP genotypes of three Orenburg populations sampled in 2017 and 2019, Altai Mountain, Altai White, and Soviet Mohair breeds, were added to the dataset. Results: Principal component analysis and network and admixture analyses demonstrated that the genetic background inherent to the archived group of Orenburg goats was maintained in all modern populations. Values of genetic diversity indicators in modern populations were compatible with those obtained in comparison groups. Runs of homozygosity (ROH) were found in all the Orenburg goat populations (with a mean ROH length of 72.6–108.9 Mb and mean ROH number of 28–36). Genomic inbreeding based on ROH was low in all the Orenburg populations (FROH = 0.03–0.045). Conclusions: We showed that the ancestral background is retained in present-day Orenburg goats sampled in 2024. We provide the genetic basis through which certain breeder animals may be selected and bred traditionally or ex situ through a conservation program of gamete preservation. [ABSTRACT FROM AUTHOR]

Evolutionary processes and selective breeding have developed diverse arrays of local livestock populations adapted to specific natural and climatic conditions. Increased selection pressure and concentration on a few high-yielding breeds have led to the erosion of genetic resources worldwide. One of effective approaches to assessing genetic diversity is the study of mitochondrial DNA (mtDNA) polymorphism, which exhibits a high level of variability and is characterized by a lack of recombination, allowing the study of genetic relationships between breeds and the tracing of both ancient and relatively recent evolutionary events. The study of the evolution and demographic history of farm animal breeds is possible due to the involvement of historical and archaeological specimens in research. The aim of our work was to identify the most efficient way to investigate mitochondrial DNA extracted from archaeological samples, allowing the analysis of population genetic parameters. The study included samples dating from the late 13th–14th centuries, discovered during excavations of the central part of the medieval Kremlin within the boundaries of modern Yaroslavl. The methods of full-genome sequencing and Sanger sequencing of mtDNA fragments were used to study the maternal variability of cattle bred in the forest zone of the Russian Plain. A dendrogram based on genetic distances of the complete mitochondrial sequence using the neighbor-joining method revealed clustering of archaeological samples in groups of modern Yaroslavl and Kholmogory cattle, which may indicate common ancestors of all three populations. A detailed examination of some regions of the mitogenome revealed that the archaeological samples were successfully genotyped with sequences that slightly overlapped with each other. Therefore, a system for genotyping the hypervariable region of the D-loop using Sanger sequencing of the target fragment was developed. The analysis of nucleotide and haplotypic diversity revealed minimal values of these parameters in the group of archaeological samples. The constructed median haplotype network allowed to attribute the archaeological samples to haplogroup T3, the most widespread in European cattle breeds. The analysis of the obtained data allows us to assume that the studied archaeological specimens originated from individuals of the local group of cattle bred in the vicinity of medieval Yaroslavl in the 13th–14th centuries. [ABSTRACT FROM AUTHOR]

Cattle breeds used in industrial production tend to have a larger size compared to the local cattle, as the increased dairy and beef productivity is closely related to the stature. The aim of our work was to identify single nucleotide polymorphisms (SNPs), which are significantly associated with stature in diverse cattle breeds. Thirteen local and transboundary cattle breeds (n = 670) subjected to our study were divided in two groups according to the stature. The high-stature group included Angus, Ayrshire, Black-and-White, Holstein, Kholmogor, Yaroslavl, Tagil and Istoben breeds. The low-stature group comprised of Jersey, Kalmyk, Kyrgyz, Mongolian and Yakut cattle. The average height at withers was 136.3 ± 1.6 and 121.6 ± 2.8 cm in the high- and low-stature groups, respectively. The samples of 11 breeds were genotyped using high-density DNA arrays (Illumina Inc., USA). The genotypes of two remaining breeds were downloaded from the publicly available WIDDE database. Genome-wide association studies revealed four SNPs, which were strongly associated with the stature, including three SNPs at 77.3–77.8 cM on BTA4 (map53144-ss46525999, p < 7.747 × 10−101; BovineHD0400021479, p < 1.173 × 10−91; ARS-BFGL-NGS-116590, p < 7.665 × 10−105) and one SNPs at 25.2 cM on BTA14 (BovineHD1400007259, p < 1.324 × 10−109). Functional annotation showed the localization within identified regions of genes, which are responsible for growth, exterior characteristics, protein and lipid metabolism, and feed intake. Identified SNPs can be considered as useful DNA markers for marker-assistant cattle breeding aimed at increased stature. The study was funded by the Russian Ministry of Science and Higher Education No. 0445-2019-0024. [ABSTRACT FROM AUTHOR]

Summary: Copy number variants (CNVs) are genomic structural variations that contribute to many adaptive and economically important traits in livestock. In this study, we detected CNVs in 354 animals from 16 Russian indigenous sheep breeds and analysed their possible functional roles. Our analysis of the entire sample set resulted in 4527 CNVs forming 1450 CNV regions (CNVRs). When constructing CNVRs for individual breeds, a total of 2715 regions ranging from 88 in Groznensk to 337 in Osetin breeds were identified. To make interbreed CNVR frequency comparison possible, we also identified core CNVRs using CNVs with overlapping chromosomal locations found in different breeds. This resulted in 137 interbreed CNVRs with frequency >15% in at least one breed. Functional enrichment analysis of genes affected by CNVRs in individual breeds revealed 12 breeds with significant enrichments in olfactory perception, PRAME family proteins, and immune response. Function of genes affected by interbreed and breed‐specific CNVRs revealed candidates related to domestication, adaptation to high altitudes and cold climates, reproduction, parasite resistance, milk and meat qualities, wool traits, fat storage, and fat metabolism. Our work is the first attempt to uncover and characterise the CNV makeup of Russian indigenous sheep breeds. Further experimental and functional validation of CNVRs would help in developing new and improving existing sheep breeds. [ABSTRACT FROM AUTHOR]