Metaphylactic treatment strategies with toltrazuril and diclazuril and growth performance of buffalo calves exposed to a natural eimeria infection.

Five controlled field trials were conducted in southern Italy to evaluate the effect of metaphylactic treatment strategies of toltrazuril and diclazuril for the control of coccidiosis in water buffaloes naturally infected by Eimeria spp. The 5 farms were divided into two types (A and B) according to their management system (individual or collective breeding of buffalo calves). In the farms of type A (no. 3), the buffalo calves were bred in individual boxes from the birth to the 7th/8th week of age and then transferred to concrete based pens; in the farms of type B (no. 2) the calves were bred in groups on concrete based pens from the birth. On each farm, 36 calves aged 5 weeks were divided at random into three similar groups of 12. One group was treated with toltrazuril (TOL), the second group was treated with diclazuril (DIC) and the third group was remained as untreated control group (CONT). On each farm the calves were weighed weekly and clinically examined. In the 5 buffalo farms the average oocyst excretion decreased significantly in both the treated groups (TOL and DIC), however the TOL groups had significantly low counts than the DIC groups. The body-weight gains recorded fortnightly were significantly higher in the TOL groups (range=5.4-8.1 kg) compared to the DIC (range=1.7-3.1 kg).