Egyptian Journal of Veterinary Sciences

GOAT MILK is considered one of the most important types of food in the world, as it is easy to digest for children and adults, and expensive cheese is made from it. Prolactin (PRL) and alpha casein 2 (CS1N2) genes are considered as biomarker selection for milk production in farm animals. The present study aimed to identify different genotypes and single nucleotide polymorphisms (SNPs) in PRL and CS1N2 genes correlated with milk traits in Damascus and Zaraiby goats. Sixty milk and blood samples were collected from Damascus (n=30) and Zaraiby (n=30) goat farm in Kafr El-Sheikh, Egypt. Different milk traits were determined in collected milk samples using biochemical methods. Different genotypes of PRL, CS1N2a and CSN1N2b genes were detected by SSCP-PCR technique. The results of biochemical analysis for milk samples showed that fat, protein, lactose, and solid non-fat (SNF) levels were (3.83, 3.7, 4.3, and 7.7) in Zaraiby goat milk, higher than Damascus goat milk (3.1, 3.3, 4.2, and 7.4). While pH levels were (6.63) in Damascus goat milk, higher than Zaraiby goat milk (6.62), the statistical analysis showed that differences between Damascus goat and Zarariby goat were significant in fat content and non-significant in other components PRL, CS1N2a and CSN1N2b fragments were detected by specific primers at 208 bp, 270 bp, and 230 bp, respectively. The results of SSCP-PCR analysis showed that PRL, CS1N2a, and CS1N2b were monomorphic patterns. This study recommends examining other places in these genes to detect new SNPs to explain the reasons for increased milk composition in Zaraiby goats compared to Damascus goats.