Experimental infestation to gastrointestinal nematodes in sheep (clinical and parasitological finding)

This survey was designed to study the parasitological features and clinical symptoms due to the infestation of gastrointestinal nematodes in sheep. Two sheep naturally infested to gastrointestinal nematodes were obtained and were selected as egg donors. For experimental infestation eight free worm lambs (5-6 months old) were selected and 50000 of third stage larvae of gastrointestinal nematodes that were obtained from eggs of donor sheep were fed to each of them. Four other lambs received placebo (control group). Daily stools from infected sheep were taken for parasitological examinations. Body weight and clinical symptoms were recorded. Twelve, 21, 35 and 60 days after infestation two lambs were slaughtered and established worms from fed larvae were counted. Results were analyzed by ANOVA. No clinical symptoms (except anemia) were found in the animals during this study however body weight is monitored during 60 days post infestation and indicated a significantly difference between live weight in infested and control groups. The adult worms occurred from fed larvae were 2665 (5.3%) and maximum E.P.G at 35th day post infestation was recorded. The lengths of male and female worms in the abomasums were 13.2 and 20.8 mm respectively. Also worms at 35th day post infestation had high size.