Association between the Ovine MHC-DRB1 Gene and its Resistance to Gastrointestinal Parasites in Deccani Sheep Raised in Hot Semi-arid Ecosystem of India

Abstract

Backgroung: Major histocompatibility complex (MHC) is linked with the ability of sheep to resist infection by GIN as measured by feacal egg count. Present study was carried out to genotype Deccani sheep for DRB1 locus and associate it with parasitic resistance. Methods: PCR SSCP analysis for Ovar-DRB1 exon 2 and part of intron-1 was carried out under optimum conditions. Effect of genetic and nongenetic factors along with the genotype was performed using linear model of least square analysis by considering log transferred faecal egg count as a dependent variable. Result: PCR SSCP analysis revealed presence of 14 SSCP patterns. The factors such as age, sex, farm and birth type demonstrated a non significant effect on faecal egg count however, season was observed to be significant source of variation. Further, it was observed that, genotype J and F could be possibly associated with resistance and susceptibility to parasitic infection. Thus, it was inferred that DRB1 gene is may be associated with immune response to parasitic invasion and selection for genotype associated with Ovar-Mhc-DRB1 gene could improve the parasitic resistance in Deccani sheep.