ABSTRACT
BACKGROUND: Haemonchus contortus causes severe economic losses in small ruminants, so this study was conducted to study the UV effect on H. contortus larvae and its protective effect. METHODS: Sixteen male goats were divided into 5 groups, control infected, control uninfected and UV 30 minutes exposure; UV 60 minutes exposure and UV booster 60 minutes exposure. The UV groups were exposed to UV irradiation at wave length 254 nm for 30 and 60 minutes. The UV booster 60 min was administrated 2 doses of exposed larvae with an interval of one month. All groups except the control negative one were challenged for 42 days from the beginning. RESULTS: In UV booster 60 min had reduction in egg count per gram feces and worm burden (93% & 34 % respectively). The establishment rate and relative fertility declined in comparison with other groups. These parameters were similar in control infected, UV 30 min and UV 60 min groups. PCV value of UV booster 60 min group was similar to uninfected group. After two weeks from the booster dose of irradiated larvae, increased levels of antibody were found in goats of UV booster 60 min group. CONCLUSION: Two doses of UV 60 min exposure, with an interval of one month, gave reduction not only in egg per gram feces but in worm burden as well.