Effect of praziquantel on Dicrocoelium dendriticum in naturally infected sheep

Dicrocoeliosis is poorly known and often underestimated by studies and practitioners in many countries. The prophylaxis of Dicrocoelium has been difficult and unsatisfactory to date due to the complexity of its biological life cycle and epidemiology (Otranto and Traversa, 2002). This study was performed to evaluate the efficacy of praziquantel at 50 mg/kg b.w. against D. dendriticum. Thirty-four sheep (11 male + 13 female), naturally infected with D. dendriticum, were allocated to two groups as follows: Treatment group 50.0 mg/kg b.w., n=14; Control group, n=10. Sheep were around 8-12-months-old. Sheep were randomized with equal groups based on mean weight and sex. Feces were collected two times before treatment and 2-7 days after treatment and just before slaughter. During the study feces were examined for parasite eggs microscopically. Equal numbers of animals (3 from each group) were slaughtered 9, 10, 11 and 12 days after treatment and livers with the bile sack and small intestine contents examined for the presence of parasites. It was concluded that praziquantel at the dose rates used in the study was 95.9% effective against D. dendriticum.