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A study for genomic variation that may reflect putative selective signaling and be associated with economically important traits is instrumental for obtaining information about demographic and selection history in domestic animal species and populations. A rich variety of the Russian chicken gene pool breeds warrants a further detailed study. Specifically, their genomic features can derive implications from their genome architecture and selective footprints for their subsequent breeding and practical efficient exploitation. In the present work, whole genome genotyping of 19 chicken breeds (20 populations with up to 71 samples each) was performed using the Chicken 50 K BeadChip DNA chip. The studied breed sample included six native Russian breeds of chickens developed in the 17th–19th centuries, as well as eight Russian chicken breeds, including the Russian White (RW), created in the 20th century on the basis of improving local chickens using breeds of foreign selection. Five specialized foreign breeds of chickens, including the White Leghorn (WL), were used along with other breeds representing the Russian gene pool. The characteristics of the genetic diversity and phylogenetic relationships of the native breeds of chickens were represented in comparison with foreign breeds. It was established that the studied native breeds demonstrate their own genetic structure that distinguishes them from foreign breeds, and from each other. For example, we previously made an assumption on what could cause the differences between two RW populations, RW1 and RW2. From the data obtained here, it was verified that WL was additionally crossed to RW2, unlike RW1. Thus, inherently, RW1 is a purer population of this improved Russian breed. A significant contribution of the gene pool of native breeds to the global genetic diversity of chickens was shown. In general, based on the results of a multilateral survey of this sample of breeds, it can be concluded that phylogenetic relationships based on their genetic structure and variability robustly reflect the known, previously postulated and newly discovered patterns of evolution of native chickens. The results herein presented will aid selection and breeding work using this gene pool.

Cattle breeds used in industrial production tend to be larger than local cattle, as increased dairy and beef productivity is closely related to stature. This study aimed to identify single nucleotide polymorphisms (SNPs) significantly associated with stature in diverse cattle breeds. Thirteen local and transboundary cattle breeds (n = 670) were divided into two groups according to their stature. The high-stature group included the Angus, Ayrshire, Black-and-White, Holstein, Kholmogor, Yaroslavl, Tagil, and Istoben breeds. The low-stature group included Jersey, Kalmyk, Kyrgyz, Mongolian, and Yakut. 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 the 11 breeds were genotyped using high-density DNA arrays. Genotypes of the two remaining breeds were downloaded from the publicly available WIDDE database. Genome-wide association studies revealed seven SNPs strongly associated with stature, including three at 77.3–77.8 cM on BTA4 and four at 24.5–25.2 cM on BTA14. Functional annotation showed the localization within identified regions of genes responsible for growth, exterior characteristics, protein and lipid metabolism, and feed intake. The identified SNPs can be considered useful DNA markers for marker-assisted cattle breeding aimed at increasing stature.

The Dagestan Mountain (DM) cattle breed was established to provide cheese and milk products to mountain dwellers in the specific conditions of the Republic of Dagestan in Southern Russia. Only 650 head of DM cattle were registered in 2020, and their “breed purity” is questionable. We aimed to assess the genetic diversity and population structure of modern DM cattle using short tandem repeat (STR) markers. The sample included 150 animals collected from private owners in Dagestan during a scientific expedition (n = 32) and provided by a gene pool farm (n = 118). An additional 166 samples from other cattle breeds distributed in the breeding zone of DM cattle were used as the comparison groups. The genotypes for the 11 STR loci recommended by ISAG were obtained using a genetic analyzer. We identified a high level of genetic diversity as revealed by allelic richness calculations (Ar = 6.82 vs. 4.38–5.82 in other cattle breeds) and observed heterozygosity indices (uHe = 0.76 vs. 0.65–0.72). Based on the STRUCTURE results, animals with low levels of admixture with other breeds were found within the DM cattle, which can be considered as candidates for use in germplasm conservation programs.

Comparison of genomic footprints in chicken breeds with different selection history is a powerful tool in elucidating genomic regions that have been targeted by recent and more ancient selection. In the present work, we aimed at examining and comparing the trajectories of artificial selection in the genomes of the native egg-type Russian White (RW) and meat-type White Cornish (WC) breeds. Combining three different statistics (top 0.1% SNP by FST value at pairwise breed comparison, hapFLK analysis, and identification of ROH island shared by more than 50% of individuals), we detected 45 genomic regions under putative selection including 11 selective sweep regions, which were detected by at least two different methods. Four of such regions were breed-specific for each of RW breed (on GGA1, GGA5, GGA8, and GGA9) and WC breed (on GGA1, GGA5, GGA8, and GGA28), while three remaining regions on GGA2 (two sweeps) and GGA3 were common for both breeds. Most of identified genomic regions overlapped with known QTLs and/or candidate genes including those for body temperatures, egg productivity, and feed intake in RW chickens and those for growth, meat and carcass traits, and feed efficiency in WC chickens. These findings were concordant with the breed origin and history of their artificial selection. We determined a set of 188 prioritized candidate genes retrieved from the 11 overlapped regions of putative selection and reviewed their functions relative to phenotypic traits of interest in the two breeds. One of the RW-specific sweep regions harbored the known domestication gene, TSHR. Gene ontology and functional annotation analysis provided additional insight into a functional coherence of genes in the sweep regions. We also showed a greater candidate gene richness on microchromosomes relative to macrochromosomes in these genomic areas. Our results on the selection history of RW and WC chickens and their key candidate genes under selection serve as a profound information for further conservation of their genomic diversity and efficient breeding.

The comparative molecular genetic study of museum and modern representatives of cattle breeds can help to elucidate the origin and maintenance of historical genetic components in modern populations. We generated the consensus genotypes for 11 microsatellite loci for 24 museum samples of Kalmyk, Kyrgyz, and Kazakh cattle, dated from the first quarter of the 20th century, and compared them with those of modern Kalmyk, Kyrgyz, and Kazakh white-headed breeds. The level of genetic diversity of the modern Kalmyk and Kyrgyz cattle (uHe = 0.771–0.778) was similar to those observed in the museum samples (uHe = 0.772–0.776), while a visible decrease in genetic variability in the modern Kazakh white-headed breed compared to museum Kazakh cattle was detected (uHe = 0.726 and 0.767, respectively). The PCA plot, FST- and Jost’s D-based networks, and STRUCTURE clustering provided strong evidence of the maintenance of the historical genetic background in modern populations of Kalmyk and Kyrgyz cattle. In spite of the allele pool of Kazakh white-headed cattle having undergone great changes compared to the museum Kazakh cattle, several animals still carry the visible aspect of the historical genetic components. Our results can be used for the selection of individuals for the creation of gene banks and may significantly improve the efficiency of conservation programs aimed at preserving genetic diversity in the national genetic resources of cattle.