Prevalence of gastrointestinal helminthoses in Garole sheep and selection of resistant and susceptible sheep using phenotypic indicator of gastrointestinal nematode resistance

The prevalence of naturally occurring gastrointestinal (GI) helminthoses inGarole sheep was determined in the present study with a view to select/identify resistant and susceptible Garole sheep.For the study, 45 Garole sheep of 4-12 months old of either sex were selected.Monthly per-rectal faecal samples were examined by both qualitative and quantitative methods, and coprocultural examination was done.The resistant and susceptible Garole sheep were selected on the basis of monthly faecal egg count (FEC) as an indicator of host resistance.The overall prevalence of GI helminthoses in Garole sheep was 63.70% with the highest prevalence of strongyle group of nematodes (57.40%).The prevalence (76.11%) as well as the intensity of infection (mean FEC = 432.22)was highest during the monsoon season.Haemonchus contortus (64.83%) was the predominant GI nematode species.The prevalence and intensity of GI helminth infection were higher in younger sheep compared to adult sheep.Seventeen (17) Garole sheep showed consistently low EPG ranging from 0 to 300 and those sheep were identified as resistant.About 45% of adult sheep and 32% of young sheep were identified as resistant based on their consistently low FEC (mean FEC<100).Rests of the 28 sheep were identified as susceptible as they exhibited a variable FEC ranging from 0 to 1200 EPG during the study period.The results of the present study could be exploited for strategic anthelmintic treatment in the farm.The resistance and susceptibility of Garole sheep, as observed in the present study, should be confirmed by further experimental studies.