Yakutian Cattle Research Articles

Runs of Homozygosity Decipher Genetic Diversity in Cattle Breed Dwelling in the Colder Regions of the World

Background: Our study focuses on Yakutian cattle, a Siberian native breed, examining its inbreeding and diversity through genome-wide analysis of runs of homozygosity (ROHs). Yakutian cattle are adapted to Siberia’s harsh sub-arctic conditions, enduring temperatures below −70°C. However, the population genetics studies on this breed are scanty, to document the genetic uniqueness in these cattle. Results: We analyzed 40 Yakutian cattle with strict quality control for ROH detection yielding 683 homozygous segments, averaging 17 per individual with an average length of 9 Mb. ROH regions were found to be involved in important pathways pertaining to cold adaptation. Autozygosity ranged from 1% to 12% of the genome, with a relatively low average inbreeding coefficient (FROH) of 0.057, as compared to other breeds. Also, the different diversity indicators, namely, principal component analysis, heterozygosity, and effective population size analysis, revealed the prevalence of genetic diversity within the breed. Conclusion: Our findings on ROH are the first of its kind in Yakutian cattle that support their adaptability to colder environments, as evidenced by low inbreeding and high genetic diversity.

Состояние породных ресурсов крупного рогатого скота в генофондных хозяйствах России

Abstract. The purpose of the research was to assess the effectiveness of the production use of small breeds of cattle bred in the country's gene pool farms. Methods. The purpose set in the study was achieved through the use of methods of analysis and generalization using special scientific literature on the problem being analyzed, a yearbook on breeding work in dairy cattle breeding on farms of the Russian Federation, and periodicals. Object of study: cattle breeds of gene pool farms in Russia (Bestuzhev, Mountain cattle of Dagestan, Istoben, Caucasian brown, red steppe, Tagil, Yakut cattle, Pechora type of Kholmogory breed). Results. Among all the breeds bred in gene pool farms, the latest ripening ones, which took the longest to reach the age of first calving, were Yakut cattle, as well as individuals of the Istoben and Red Steppe breeds, in which it varied within 33.4–35.3 months. It should be noted as a positive pattern that the animals of the Tagil breed achieved the analyzed indicator early, which was 26 months. The optimal duration of the period from calving to fertile insemination was distinguished by cows from the gene pool farms of the Republic of Dagestan – Mountain cattle of Dagestan and Caucasian brown – 71 and 74 days, respectively, as well as the breeding stock of the Bestuzhev breed – 86 days. The longest duration of the service period was recorded in the herds of gene pool farms of the Istoben breed and the Pechora type of the Kholmogory breed. The early age of retirement of Yakut cattle raises concerns, which, along with the small number of cows in this breed, will reduce not only the reproduction of the herd, but will also lead to the complete disappearance of this population. The lowest yield of calves per 100 cows is characterized by animals of the Pechora type of the Kholmogory breed – 63,1; for all other breeds it varies between 80–91 calves. Scientific novelty. For the first time, monitoring of the numbers and current state of industrial use of small breeds of dairy cattle in gene pool farms in Russia was carried out.

Adipose gene expression profiles in Northern Finncattle, Mirandesa cattle, Yakutian cattle and commercial Holstein cattle.

The drastic change in global climate has led to in-depth studies of the geneticresources of native cattle adapted to challenging environments. Native cattle breeds may harbor unique genetic mechanisms that have enabled them adapt to their given environmental conditions. Adipose tissues are key factors in the regulation of metabolism and energy balance and are crucial for the molecular switches needed to adapt to rapid environmental and nutritional changes. The transcriptome landscape of four adipose tissues was used in this study to investigate the differential gene expression profiles in three local breeds, Yakutian cattle (Sakha Republic), Northern Finncattle (Finland), Mirandesa cattle (Portugal) and commercial Holstein cattle. A total of 26 animals (12 cows, 14 bulls) yielded 81 samples of perirenal adipose tissue (n = 26), metacarpal adipose tissue (n = 26), tailhead adipose tissue (n = 26) and prescapular adipose tissue (n = 3). More than 17,000 genes were expressed in our dataset. Principal component analysis of the normalized expression profiles revealed a differential expression profile of the metacarpal adipose tissue. We found that the genes upregulated in the metacarpal adipose tissue of Yakutian cattle, such as NR4A3, TEKT3, and FGGY, were associated with energy metabolism and response to cold temperatures. In Mirandesa cattle, the upregulated genes in perirenal adipose tissue were related to immune response and inflammation (AVPR2, CCN1, and IL6), while in Northern Finncattle, the upregulated genes appeared to be involved in various physiological processes, including energy metabolism (IGFBP2). According to the sex-based comparisons, the most interesting result was the upregulation of the TPRG1 gene in three tissues of Yakutian cattle females, suggesting that adaptation is related to feed efficiency. The highest number of differentially expressed genes was found between Yakutian cattle and Holstein, several of which were associated with immunity in Yakutian cattle, indicating potential differences in disease resistance and immunity between the two breeds. This study highlights the vast difference in gene expression profiles in adipose tissues among breeds from different climatic environments, most likely highlighting selective pressure and the potential significance of the uniquely important regulatory functions of metacarpal adipose tissue.

Diversity of the infusoria symbiofauna of cattle

Infusoria from the digestive tract of herbivorous mammals have been known to science for almost a century and a half. However, protozoans remain an understudied group of rumen dwellers in ruminants. In cattle, in a multi-chambered stomach, in addition to microorganisms (fungi and bacteria), there are a large number of protozoa (infusoria), which also participate in the digestive processes that support the vital activity of the body. Endobiontic infusoria take an active part in the digestion of complex carbohydrates, fiber, in the breakdown of indigestible polysaccharides, which are essential sources of energy for animals. In this regard, the study of the species and quantitative composition of the infusoria fauna of cattle bred in the Far North, as one of the factors of sustainable adaptation to extreme conditions, is of great scientific and practical interest.This article presents the results of a study of endobiontic infusoria of cattle breeds bred in Yakutia. A total of 36 species have been identified and described in 12 genera and 3 families. It was found that the genus Entodinium and the genus Isotricha were the most represented in the Yakut cattle, while the genus Entodinium and Euplodiniumin are in the crossbred and cultivated cattle. The smallest genus in all groups are Polyplastron and Metadinium.

Preliminary Estimation of Nutritional Quality of the Meat, Liver, and Fat of the Indigenous Yakutian Cattle Based on Their Fatty Acid Profiles.

The Yakutian cattle is an indigenous Siberian cattle breed living in an extremely cold climate in some parts of Yakutia. There are only a few thousand animals of this breed, and the conservation of the Yakutian cattle is embedded in the international agenda. We studied the fatty acid profiles in the meat, liver, and fat of the Yakutian cattle (five individuals) of different ages and their main food resource-pasture plants. The fatty acid profile of the tissues of the Yakutian cattle differed from that of pasture plants: 16:0, 18:2n-6, and 18:3n-3 dominated in the pasture plants; 16:0, 18:0, 18:1n-9, 18:2n-6, 20:4n-6, 20:5n-3, and 22:5n-3 dominated in the meat and liver; and 16:0, 18:0, and 18:1n-9 dominated in the fat. The fatty acid composition of food products is related to the risk of developing cardiovascular disease (CVD). The meat and liver of the Yakutian cattle are health food products that contribute to decreasing the risk of developing CVD because of their rather high content of eicosapentaenoic and docosahexaenoic fatty acids, optimal n-6/n-3 and polyunsaturated fatty acids/saturated fatty acids ratios, low values of indexes of atherogenicity and thrombogenicity, and high values of hypocholesterolemic/hypercholesterolemic and health-promoting indexes. The results of the present study support the importance of preserving this valuable cattle breed. Actions should be taken to increase their population while retaining their contemporary housing and feeding conditions.

The content of zinc and selenium in local food products of Yakutia

Deficiency of the necessary complex of micronutrients under abnormal nutrition structure creates a problem for the preservation of health and performance of the population. In this regard, it is very relevant to develop a science-based strategy for the consumption of traditional Yakut national food that have a high nutritional value and are able to satisfy the requirements of the human body in micronutrients. The purpose of the research was to investigate the content of selenium and zinc in the local foods which are most commonly consumed by the population of Yakutia. Material and methods. The objects of study were meat (7-9 cuts each) and offal (9-11 species each) of the Yakut cattle breed (2 bulls at the age of 2.5 years), of the Yakut horse foals (3 heads at the age of 6 months), northern domestic deer (3 heads), and whitefish (Coregonus muksun), Yakut crucian carp (Carassius carassius jacuticus), lake minnow [Phoxinus percnurus (Pallas)] (3 kg each). The trace elements, zinc and selenium, were determined by infrared spectroscopy. Results. The greatest amount of zinc in the meat of farm animals was noted in the meat of Yakut cattle (6.8±0.3 mg/100 g) and Yakut horse foals (6.7±0.2 mg/100 g), and the lowest - in the meat of domestic reindeer (1.5±0.1 mg/100 g). In terms of selenium content, the meat of domestic reindeer had the highest indicators (37.0±1.0 μg/100 g), and the meat of Yakut cattle had the lowest (19.0±0.8 μg/100g). The highest concentration of zinc and selenium was found in by-products of reindeer: zinc level in the heart and liver was 12.8 mg/100 g, in the small intestine and rennet - 19.0-20.4 mg/100 g, selenium level in the colon and rennet was 41.0-46.7 μg/100 g. The content of zinc and selenium in the fresh-water muksun belly (2.14±0.08 mg and 45.0±1.8 μg in 100 g) was 32.3-37.2% higher than in the fillet of muksun, and selenium level was 3 fold higher than in the Yakut carp and in the lake minnow. The consumption of 100-200 g of meat or by-products of Yakut cattle, Yakut horse foals, by-products of reindeer or Yakut crucian carp can fully cover the daily requirement of an adult in zinc. The consumption of 200 g of venison or muksun completely covers the daily need for selenium, while the portion of the other studied products contains about half or more of recommended daily intake of this trace element. Conclusion. The data presented in the article show that the population of Yakutia, with a rational diet with local products, can meet the requirements in selenium and zinc in accordance with physiological needs.

Copy Number Variants in Two Northernmost Cattle Breeds Are Related to Their Adaptive Phenotypes.

Copy number variations (CNVs) are genomic structural variants with potential functional and evolutionary effects on phenotypes. In this study, we report the identification and characterization of CNVs from the whole-genome resequencing data of two northernmost cattle breeds from Russia: the Yakut and Kholmogory cattle and their phylogenetically most related breeds, Hanwoo and Holstein, respectively. Comparisons of the CNV regions (CNVRs) among the breeds led to the identification of breed-specific CNVRs shared by cold-adapted Kholmogory and Yakut cattle. An investigation of their overlap with genes, regulatory domains, conserved non-coding elements (CNEs), enhancers, and quantitative trait loci (QTLs) was performed to further explore breed-specific biology and adaptations. We found CNVRs enriched for gene ontology terms related to adaptation to environments in both the Kholmogory and Yakut breeds and related to thermoregulation specifically in Yakut cattle. Interestingly, the latter has also been supported when exploring the enrichment of breed-specific CNVRs in the regulatory domains and enhancers, CNEs, and QTLs implying the potential contribution of CNVR to the Yakut and Kholmogory cattle breeds’ adaptation to a harsh environment.

On the problem of population conser-vation: the study of the reproductive characteristics of the Yakut cattle

The spontaneous nature and unpredictability of the cycling of the reproductive system of cows and heifers of the Yakut breed against the background of a low level of feeding, the structure of the herd of different ages does not allow planning work on insemination of animals. In addition, one of the negative aspects that complicate the work of reproduction in the gene pool farm is the location of these farms in the immediate vicinity of settlements, where a considerable number of livestock of other breeds are kept in organized and private farms. This greatly complicates the planned mating in order to keep the gene pool clean. In this regard, it is necessary to develop methods for induced estrus and ovulation of cows and heifers in order to control the reproductive function of cows and heifers of the Yakut breed in certain periods. This will make it possible to plan early mating in a shorter time, so that by the beginning of the pasture season, the breeding stock of Yakut cattle will be pregnant. An analysis of the breeding period in the gene pool farm for Yakut cattle, carried out after hormonal stimulation of Yakut cows, showed that the duration of the service period was reduced and averaged 68 days. As a result of the application of the scheme developed by us, young cows 4-6 years old were covered with bulls, pregnancy occurred on average in 2.22 hunts, 9-11 years old - in 3.33 hunts, in cows 12 and older - in 2.2 hunts.

Adaptation features of the yakut cattle breed

Adaptation features of the yakut cattle breed

Resequencing the Yaroslavl cattle genomes reveals signatures of selection and a rare haplotype on BTA28 likely to be related to breed phenotypes.

The genomes of local livestock could shed light on their genetic history, mechanisms of adaptations to environments and unique genetics. Herein we look into the genetics and adaptations of the Russian native dairy Yaroslavl cattle breed using 22 resequenced individuals and comparing them with two related breeds (Russian Kholmogory and Holstein), and to the taurine set of the 1000 Bull Genomes Project (Run 9). HapFLK analysis with Kholmogory and Holstein breeds (using Yakut cattle as outgroup) resulted in 22 regions under selection (q‐value < 0.01) on 11 chromosomes assigned to Yaroslavl cattle, including a strong signature of selection in the region of the KIT gene on BTA6. The F ST (fixation index) with the 1000 Bull Genomes Dataset showed 48 non‐overlapping top (0.1%) F ST regions of which three overlapped HapFLK regions. We identified 1982 highly differentiated (F ST > 0.40) missense mutations in the Yaroslavl genomes. These genes were enriched in the epidermal growth factor and calcium‐binding functional categories. The top F ST intervals contained eight genes with allele frequencies quite different between the Yaroslavl and Kholmogory breeds and the rest of the 1000 Bull Genomes Dataset, including KAT6B, which had a nearly Yaroslavl breed‐specific deleterious missense mutation with the highest F ST in our dataset (0.99). This gene is a part of a long haplotype containing other genes from F ST and hapFLK analyses and with a negative association with weight and carcass traits according to the genotyping of 30 phenotyped Yaroslavl cattle individuals. Our work provides the industry with candidate genetic variants to be focused on in breed improvement efforts.

IN SEARCH OF MYTH AND REAL HISTORICAL EVENTS

Elley and Omogoy are considered the legendary ancestors of the Sakha (Yakuts), the indigenous people of North-Eastern Siberia. We have put forward a hypothesis that the legendary Elley is a historical person and the first pastoralists in the territory of the middle Lena. The aim of the study search for Elley historical prototype and determine the probable time of his arrival in the middle Lena and the origins of cattle breeding in this territory. Subjects and methods. The analysis of all the existing versions of the legends about Elley, data from humanitarian, historical, archaeological, genetic studies, which have a connection with the historical prototype of the hero. Results. Analyzing the Sakha legends about the ancestors, we concluded that the personalities and events described in these legends are based on real historical facts. Probably, cattle began to breed on the territory of Yakutia during the rise of the Xiongnu at the beginning of our century. Conclusion. A number of scientific facts indicate an earlier period of the appearance of the Yakut cattle breed in Yakutia. At the present time, we can state with a certain degree of probability that the personality of Elley is connected with the events that took place in the XII century in East Asia during the period of Song China.

Comparative analysis of allele frequencies for DNA polymorphisms associated with disease and economically important traits in the genomes of Russian and foreign cattle breeds.

The genetic makeup of a breed including its genetic differences from other breeds determines its appearance and characteristics, including economically important traits and resistance to pathologies. To date, many loci controlling significant phenotypes have been identified, which is successfully used in the world practice of marker-assisted selection to improve breed properties. The aim of this study was a comparative analysis of frequencies for known causative nucleotide substitutions, insertions and deletions associated with disease and economically important traits in Russian and foreign cattle breeds. As a result, we identified frequencies of these DNA polymorphisms in the populations of Russian cattle breeds, compared them with those of foreign populations of the same breed, as well as other foreign breeds. Our results indicate similarities in frequencies for most of such alleles within breeds (populations of Russian and foreign breeding), as well as the relationship between the causative allele prevalence and the presence of phenotypic traits under the effect. We also found an excess of some undesirable alleles in the Russian cattle populations, which should be paid attention to when designing breeding programs. We found that the alleles increasing fertility in the Hereford breed have a higher frequency in the Russian Hereford population compared to the foreign counterpart. Interestingly, unlike for the European breeds, for Asian Turano-Mongolian Wagyu and Yakut cattle, there was a less clear link between phenotypic traits and frequencies of known causative alleles. Our work points to specific genetic variants that could be used to improve and/or maintain the performance of certain cattle breeds bred in the Russian Federation

Environmental Compliance and Nutritional Value of Yakutian Cattle Products

Due to the increasing anthropogenic pollution of the environment, the environmental compliance of agricultural and livestock products becomes increasingly important. This study discusses the materials on pollutant content in the Yakutian cattle products and includes the assessment of the nutritional value of meat and milk. The research objective is to determine the content of toxic metals, microelements, and the nutritional value of meat and milk of Yakutian cattle bred in Yakutia. Research methods. Sample material was analyzed for the content of toxic metals and microelements using atomic absorption spectroscopy. Milk productivity indicators and organoleptic properties of meat were determined by conventional methods. Results. The average value of lead content in meat was determined amounting to 0.1736±0.0076 mg/kg, mercury — 0.0156±0.0012 mg/kg, arsenic — 0.006±0.0007 mg/kg. No cadmium was not found in meat. Relatively high content of toxic metals was detected in liver. The content of microelements (Zn, Cu, Fe) satisfies regulatory requirements. Relatively high content of copper (83.3076±0.2342 mg/kg) and iron (97.4148±0.4412 mg/kg) was detected in liver. Conclusions. Analysis of research results showed that the average values of toxic metals content (mg/kg) (Pb, Cd, Hg, As) in meat and liver satisfy the regulatory requirements. Yakutian cattle meat contains a balanced full range of amino acids and is suitable for the production of high-quality meat products. Yakutian cattle milk has high fat content varying on average from 5.04% to 5.46%.

Adaptive Selection Tasks in Cattle Breeding in Yakutia

The article summarizes the results of the authors’ scientific works and their own research on the adaptation of Yakut cattle and their crossbreeds with the Simmental breed to specific climatic and economic conditions of keeping. The paper highlights outstanding fat content (5.5…5.58%), excellent compensatory growth energy with free summer feeding (700…900 g per day), high coefficient of digestion of coarse feed fiber (74%), Yakut cattle’s unique resistance and adaptation to adverse weather, economic conditions of breeding, the degree of their inheritance in crossbreed livestock. The article presents materials for studying the morphobiological composition of blood, thermoregulation, skin and hair cover, development of internal organs, gas-energy metabolism, digestibility and use of feed nutrients. It is indicated that when crossing Yakut cattle with Simmental breed with an increase in genetic generation of crossbreeds, its valuable economic and adaptive qualities disappear. The task of protecting the gene pool of local native Yakut cattle and increasing its livestock and geographic range, improving nutrition concerns not so much its higher productivity, but the preservation of the valuable nutritional qualities of its dairy and meat products as well as of its adaptive potential to local conditions in the offspring. When local Simmental (87% of the population) and Kholmogorsky (12% of the population) cattle breeds are kept with generally accepted methods of artificial selection aimed at increasing productivity and improving hereditary qualities, it is necessary to simultaneously conduct adaptive selection by preserving the valuable qualities of the Yakut cattle gene pool in the offspring.

Genetic characteristics of the Pechora type of Kholmogorsky cattle based on microsatellites and DNA markers

The Pechora zonal type (PH-1) was obtained by absorbing crossbreeding of local Northern komolog cattle with the Kholmogorsky breed. Currently, Kholmogorsky cattle are on the verge of extinction, which is due to the widespread metisation of domestic Holstein breeds. The paper presents the characteristics of the allelofond of the Kholmogorsky herd of the Pechora type (n=66) by 11 polymorphic loci of microsatellites. It was found that the polymorphism of tandem repeats in the Pechora type of Kholmogorsky cattle is observed in all 11 loci, the most polymorphic is the tgla53 locus (10 alleles). The most common allele SPS115 248 occurs with a frequency of 0.606. The average number of alleles for 11 loci was 6.2, and the number of effective alleles was 3.4. the obtained indicators were compared with the values published for Yakut [1], Holstein [2, 3] and Ayrshire cattle [4]. It was found that the Pechora type of Kholmogorsky breed has a higher number of effective alleles than Yakut cattle (by 1.0), and lower than other breeds (by 0.3...1.6). Analysis of F-statistics showed that on average, the deviation of the actual heterozygosity from the expected one is insignificant Fis=-0.004, while other breeds, excluding the sample of Holstein bulls, had a more significant excess of heterozygotes. The smallest genetic distance of the studied population was established with the Holstein breed (d=0.221 to cows and d=0.200 to bulls). A more detailed genetic analysis of individual loci showed that the frequency of occurrence of alleles BM2113 Pechora type is closer to the Yakut (r=0.935) and Ayrshire (r=0.875) than to the Holstein breed (r=316...357).

Problems of adaptation of imported specialized breeds of cattle

The experience of importing Simmental breed from Austria of beef cattle Hereford breed from Novosibirsk region, red steppe breed from the Altay Territory to the Republic of Sakha (Yakutia) is analyzed. Acclimatization of imported livestock to the conditions of the Far North is hard. Of 471 heads of cattle of Austrian Simmental breed imported in 2007, 171 are currently left. The average milk production of cows per head is 2485 litres, the average figure for the Republic is 2364 litres. Of 200 heads of Herefords brought in 20112012, only 32 have remained. A brief description of the milk productivity of the red steppe breed in Yakutia is presented. Milk yield per cow amounted to 2630 litres in six lactations, which is 166 litres higher than the national average. Due to non-compliance with the requirements of the technology of keeping and feeding imported animals, 116 out of 200 imported cows have remained. The hematological parameters of cattle reflecting the state of the body's immune system during acclimatization are given. Adaptation of red steppe cows was difficult, but the hematological parameters corresponded to the physiological norm. Possible ways of developing livestock breeding programme in Yakutia to create a simmentalized Yakut zonal type of cattle, which is distinguished by exceptional adaptive abilities for keeping and feeding conditions, are proposed. Thanks to crossbreeding with Yakut cattle, the acclimatization and further breeding of imported specialized breeds and their crosses is successful. The ways of improving the technology of keeping and feeding cattle on the farms of the Republic are shown.

Whole genome studies of origin, selection and adaptation of the Russian cattle breeds

Our review presents several recent studies on the genetic history and signatures of selection in genomes of the native Russian cattle breeds. Most of these works are not easily accessible for the Russian-speaking audience. We describe the origins of appearance of the Russian cattle breeds from the genetics perspective. We point to the links between most of the Russian breeds with the taurine breeds of the European origin and for some Russian breeds with the breeds of the Asian origin. We describe major phylogenetic clusters of the Russian breeds and point to those that still maintain their unique genetics, meaning that their preservation is a priority. In addition, we review the results of the search for signatures of selection in genomes of the Russian cattle breeds. Some unique signatures of selection present in the genomes of so-called “turano-mongolian” cattle (i. e. the Yakut cattle) are described which allowed the Yakut cattle to adapt to harsh environments found above the Polar Circle. Signatures of selection which could help other cattle breeds of the Russian origin to adapt to various climatic condition of the Russian Federation are reviewed. The Russian cattle genomes also contain known signatures of selection related to cattle domestication about 8–10 thousand years ago. The most profound ones include genes related to changes of the coat colour. This phenotype in many cases could be related to the distinction of the first domesticated populations and lead to the formation of so-called land races (primitive breeds). Whole-genome association studies of Russian cattle breeds pointed to a novel gene which could be related to the “white-faced” phenotype and to a gene which is related to body temperature support under the acute cold stress. The data presented in our review could be used for identification of genetic markers to focus on in future efforts on designing new highly productive cattle breeds adapted to climates of the Russian Federation and other countries with similar climates.

Whole blood transcriptome analysis reveals footprints of cattle adaptation to sub-arctic conditions.

SummaryIndigenous cattle breeds in northern Eurasia have adapted to harsh climate conditions. The local breeds are important genetic resources with cultural and historical heritages, and therefore, their preservation and genetic characterization are important. In this study, we profiled the whole‐blood transcriptome of two native breeds (Northern Finncattle and Yakutian cattle) and one commercial breed (Holstein) using high‐throughput RNA sequencing. More than 15 000 genes were identified, of which two, 89 and 162 genes were significantly upregulated exclusively in Northern Finncattle, Yakutian cattle and Holstein cattle respectively. The functional classification of these significantly differentially expressed genes identified several biological processes and pathways related to signalling mechanisms, cell differentiation and host–pathogen interactions that, in general, point towards immunity and disease resistance mechanisms. The gene expression pattern observed in Northern Finncattle was more similar to that of Yakutian cattle, despite sharing similar living conditions with the Holstein cattle included in our study. In conclusion, our study identified unique biological processes in these breeds that may have helped them to adapt and survive in northern and sub‐arctic environments.

Whole-Genome Sequencing of Three Native Cattle Breeds Originating From the Northernmost Cattle Farming Regions.

Northern Fennoscandia and the Sakha Republic in the Russian Federation represent the northernmost regions on Earth where cattle farming has been traditionally practiced. In this study, we performed whole-genome sequencing to genetically characterize three rare native breeds Eastern Finncattle, Western Finncattle and Yakutian cattle adapted to these northern Eurasian regions. We examined the demographic history, genetic diversity and unfolded loci under natural or artificial selection. On average, we achieved 13.01-fold genome coverage after mapping the sequencing reads on the bovine reference genome (UMD 3.1) and detected a total of 17.45 million single nucleotide polymorphisms (SNPs) and 1.95 million insertions-deletions (indels). We observed that the ancestral species (Bos primigenius) of Eurasian taurine cattle experienced two notable prehistorical declines in effective population size associated with dramatic climate changes. The modern Yakutian cattle exhibited a higher level of within-population variation in terms of number of SNPs and nucleotide diversity than the contemporary European taurine breeds. This result is in contrast to the results of marker-based cattle breed diversity studies, indicating assortment bias in previous analyses. Our results suggest that the effective population size of the ancestral Asiatic taurine cattle may have been higher than that of the European cattle. Alternatively, our findings could indicate the hybrid origins of the Yakutian cattle ancestries and possibly the lack of intensive artificial selection. We identified a number of genomic regions under selection that may have contributed to the adaptation to the northern and subarctic environments, including genes involved in disease resistance, sensory perception, cold adaptation and growth. By characterizing the native breeds, we were able to obtain new information on cattle genomes and on the value of the adapted breeds for the conservation of cattle genetic resources.

GENE POOL OF NATIVE BREEDS OF LIVESTOCK IN THE REPUBLIC OF SAKHA (YAKUTIA)

The paper presents the results of many-year research into the origin, preservation and rational use of the genetic resources of native livestock breeds in the Republic of Sakha (Yakutia). These breeds are characterized by high adaptability to extreme housing conditions and severe environmental conditions. They are not exacting about feeding and are distinguished by high quality of the produce (milk, meat, sldn and products of their processing). The article analyzes natural climatic, historic, social and economic developmental characteristics of Yakut animal husbandry. The main stages of the concept implementation for breeding and raising cattle of the adapted type on the regional level are described. Themolecularandgeneticresearchtestify to the unique genetic structure of native livestock breeds (Yakut cattle, horses and reindeer). The genetic unique character and adaptability of Yakut cattle, horses and reindeer to the harsh conditions make them a valuable material for further breeding work and research into adaptation mechanisms.