Résumé
Goat’s milk production is an important activity in France. Gastro intestinal nematodes (GINs) remain a main threat for grazing goats. These worm infections are usually controlled by the use of synthetic anthelmintics (AH). However, 1) eprinomectin (EPN) is the only molecule currently available without withdrawal time for milk; 2) nematodes AH resistances increase dramatically. A survey, based on voluntary adhesion, was performed in 13 farms of Auvergne-Rhône-Alpes (AURA) region to evaluate the efficacy of 2 AH authorized in lactating goats: a benzimidazole (BZ) and an avermectin (pour-on EPN). Following the WAAVP guidelines (Wood et al, 1995, Vet Parasitol, 58, 181-213). In a first step, Fecal Egg Count Reduction Tests (FECRT) were carried out on each farm. FECRTs included 3 groups of 10 adult goats per farm: a control group, one treated orally with oxfendazole (10 mg/kg LW) and one treated with EPN pour-on (1 mg/kg LW). The survey was performed in dry goats when indoors in winter. The results indicate GIN resistance to BZs in 11 of 13 farms (84.6%) and a lack of efficacy to EPN pour-on in 10 of 13 farms (76.9%). In a second step, to confirm true resistance EPN has been given orally or subcutaneously to goats in 4 farms showing a lack of efficacy to EPN pour-on. Resistance to EPN was then confirmed in 3 out of 4 farms. Although based on a limited number of farms, these results suggest 1) the high level of resistance to BZs in dairy goat farms; 2) the lack of efficacy of pour-on EPN, with a confirmation of resistance in 3 farms; 3) the need to explore alternative options to AHs to prepare an integrated, sustainable control of GINs.