Genotype Screening of Bovine Brachyspina in Taiwan Holstein Cows

This study analyzed carrier frequencies of the genetic defect bovine brachyspina (BS) in the Holstein cows in Taiwan. In total, 1688 cows from 31 herds were included in the analysis, performed using the Igenity-Prime 50K single-nucleotide polymorphism chip. Of the 1688 cows, 68 (5.09%) were BS carriers (BY), a frequency lower than that reported in Taiwan previously. In Taiwan, the import of frozen BY bull semen has been discontinued since the implementation of an import censorship act in 2015. Pedigree analysis results indicated that 70% of the defective genotype was inherited from dam carriers. Through mating programs, the defect allele has remained in Taiwan Holstein herds. Regular screening for genetic defects is necessary eliminate the recessive BS gene from the Taiwan Holstein population.