New Cases of Bovine Leukocyte Adhesion Deficiency (BLAD) Carriers in Indian Holstein Cattle

Bovine Leukocyte Adhesion Deficiency (BLAD) is autosomal recessive genetic diseases that affects Holstein breed world wide. It is a disease characterized by reduced expression of the adhesion molecules on neutrophils. The disease caused by mutation which replaces adenine at 383 with guanine that change amino acid, aspartic acid to glycine, leading to wrong protein (CD18) that is impaired in function. Blood samples were collected from 126 Holstein phenotypically normal bulls maintained at different sperm stations in India. PCR-RFLP was performed to detect heterozygous (carrier). Results indicate that out of 120 bulls, 2 bulls (1.59%) appear to be carriers for BLAD. The gene and genotype frequency of recessive allele was estimated 0.008 and 0.016 in the 126 samples respectively. The condition is alarming and emphasizes regular screening of Holstein AI bulls and its crossbreds to avoid risk of spreading BLAD in breedable population of India.