Field trial on the efficacy of albendazole micronised (single and double treatment) against Dicrocoelium dendriticum in naturally infected sheep: a new strategy for the control of dicrocoeliosis

Dicrocoelium dendriticum is the most common liver fluke in domestic ruminants in Italy, reaching prevalence values of 67% on ovine farms in the southern regions. It causes economic losses and clinical problems. The present paper reviews the results of a controlled field trial conducted in southern Italy to evaluate the efficacy of a single or double administration of albendazole micronised against D. dendriticum in pastured sheep naturally infected by the small liver fluke. The trial was conducted in a sheep farm located in the Campania region, southern Italy. Sixty female crossbreed sheep were selected on the basis of the D. dendriticum positive faecal egg counts (FEC). Ewes were divided into 3 groups, of 20 sheep each, based on D. dendriticum FEC. One group (A-group) was treated once and the other group (B-group) treated twice at an interval of one week, whereas the control group (C-group) was untreated. The efficacy of treatment was evaluated by FEC and necropsy examination for D. dendriticum. Following the WAAVP guidelines for evaluating the efficacy of anthelmintics in ruminants, the double administration of albendazole micronized, showed a high efficacy (up to 99% based on FEC reduction), whereas the single treatment was less effective (up to 96% based on FEC reduction) against D. dendriticum. This difference was significant (P < 0–0.05). The results were also confirmed by necropsy examinations. At day 14 the mean D. dendriticum burdens of the slaughtered sheep of the A-group, B-group and C-group were 87, 70 and 1274 adults (P < 0.001), respectively following necroscopic examinations.