Abstract

This study analyzed the prevalence of genetic defect carriers of Bovine Leukocyte Adhesion Deficiency [BLAD], Complex Vertebral Malformation [CVM], Deficiency of Uridine Monophosphate Synthase [DUMPS], and mule foot in the Holstein cow population in Taiwan. In total, 1688 cows from 31 herds were analyzed and 9 [0.53%] and 30 [1.78%] were BLAD and CVM carriers, respectively. No DUMPS or mule foot carriers were discovered. Frozen semen of genetic defect-carrying bulls is no longer imported to Taiwan in accordance with import restrictions on frozen bull semen implemented in 2005. However, pedigree analysis revealed that some defective alleles remain in Taiwanese dairy herds because of the mating program. The main source of the defect genotype is dam carriers. Close monitoring is thus necessary for eliminating the recessive genetic defects from the Holstein cattle population in Taiwan.

Keywords: BLAD; CVM; DUMPS; Mule foot; Holstein cattle