Current management of farms and internal parasites by conventional and organic meat sheep French farmers and acceptance of targeted selective treatments

Summary

Sheep meat production in France is characterized by large flocks and a limited supply of labour. Digestive-tract strongyles are considered as one of the main health problems and control relies mostly on the use of anthelminthics, although resistance to at least the benzimidazoles is increasing. We conducted interviews on nine conventional and seven organic farms regarding whether an anthelmintic targeted selective treatment program could fit within the operations of the farms. In addition, necropsies of lambs were performed on three organic farms, and faecal egg counts and small lungworm counts were performed on all farms in autumn in ewes. Each interview consisted of an open discussion on sheep health and was terminated with comments on digestive-tract helminth infection as detected in parallel with the interview. Factors likely to affect the adoption of the targeted selective treatment approach were subjected to cluster analysis. Conventional farms were mostly advised by veterinarians and relied on systematic planning of anthelmintic treatments. The frequency of treatments was up to once a month for lambs and two to three times a year for ewes. The concept of selecting animals to be treated according to a scheme of targeted selective treatments based on phenotypic markers (e.g., anaemia, diarrhoea, weight gains) was not seen as feasible by these farmers. Conversely, organic farmers, with greater use of advisors and a restricted range of anthelmintic treatments were more susceptible to integrating phenotypic markers into their practices for controlling digestive-tract strongyles.