author(s)
Manoranjan Roy, PK Senapati, Manik Ch Pakhira, U Sarkar and S Datta

abstract
45 male and 58 female Garole sheep were divided into resistant, susceptible and highly susceptible groups to natural infection of Haemonchus contortus based on faecal egg count and subsequently Diallel mating was applied in two subsequent generations to study the inheritance and variability of resistance. A total of 505 lambs were examined for faecal egg count at 3^rd, 6^th and 8^th months of age. The overall resistance had been increased after Diallel mating in second and third generations as compared to parent generation. In both generations, lambs produced from resistant parents had significantly lower EPG. Highest and lowest EPG was recorded at 3^rd and 8^th month of age respectively. A high heritability of EPG was estimated in lambs of all ages in second and third generation at 3^rd, 6^th and 8^th months of age. A moderate to high repeatability was estimated for EPG in first, second and third generation. Results of this study indicate heritable variations of resistance to Haemonchus contortus in Garole sheep. Thus, selection of rams and ewes can be made as early as six months of age.