PSXIV-4 Breed purity of Holstein bulls born in Russia and imported from different countries.

Abstract

The Holstein breed of cattle is the most common among all dairy cattle breeds in Russia. It is characterized by a higher milk production than any other native breed. Here we evaluate breed purity of Holstein bulls born in Russia (RUS, n=27) in comparison with animals imported from different countries: Germany (GER,n=5), Netherlands (NED,n=4), Denmark (DEN,n=3), Belarus (BEL,n=4) and Canada (CAN,n=4) using Illumina BovineSNP50 BeadChip. To examine the level of admixture with other breeds we added Black-and-White (BLWT,n=5), Kholmogor (KHLM,n=7) and Yaroslavl (YRSL,n=10) samples to our dataset. PLINK 1.07, SplitsTree 4.14.6, Admixture 1.3 software and R package “StAMPP” were used to infer genetic relationship between the studied groups. After quality control, 27689 SNPs were selected for further analyses. MDS analysis and Neighbor-Net showed that all the breeds formed their own clusters. Holstein bulls with different origin were assigned to one group. Significant pairwise Fst values between Holstein bulls for RUS ranged from 0.003 (BEL) to 0.012 (CAN). The lowest Fst values between Holstein and BLWT, KHLM, YRSL were observed for RUS and BEL - 0.109 and 0.097, 0.134 and 0.137, 0.120 and 0.112, respectively, and the highest for CAN - 0.145, 0.178, 0.149, respectively. Admixture analysis revealed the percentage of Holstein in RUS was 88.4%, in BEL – 75%, GER – 97.8%, NED – 98.2%, DEN – 95.8% and CAN – 98.5%. We found Black-and-White, Kholmogor and Yaroslavl ancestry in RUS and BEL at proportion of 7.8% and 15.8%, 1.6% and 3.9%, and 2.2% and 5.3%. Thus, our study showed that, Holstein bulls born in Russia are similar to the animals imported from Belarus and differ from the cattle imported from Germany, Netherlands, Denmark and Canada by the presence of Russian cattle specific component. This information will be valuable for genomic selection programs. Supported by FASO, №AAAA-A18-118021590134-3.