Abstract
Avian influenza (AI) is a serious global threat to poultry and public safety, although some native chicken varieties show resilience, such as the Ri chicken in Vietnam. Major histocompatibility complex B (MHC-B), a critical component of the chicken immune system, has been shown to influence disease resistance. This study examined the MHC-B haplotype diversity in a Ri chicken population that is sensitive to AI. Ri chickens were genotyped for MHC-B single nucleotide polymorphisms (SNPs) using the Kompetitive Allele Specific Polymerase Chain Reaction (KASP). Statistical tests revealed no significant differences in allele frequencies of the SNPs between resistant (R) and susceptible (S) groups. Haplotype analysis identified 32 unique haplotypes, with only one shared haplotype between the R and S groups. However, a phylogenetic analysis did not find distinct clustering of MHC-B alleles of the Ri chicken groups. Further research with a larger sample size is recommended to establish representative group-specific haplotypes and enhance our comprehension of the intricate genetic mechanisms underlying disease resistance in poultry. The implications of this research extend to improving disease resistance strategies and guiding selective breeding practices in the poultry industry.