Resumen

CERUTTI, J. et al. Eficacia reducida de derquantel y abamectina en ovinos y caprinos con Haemonchus sp resistentes a lactonas macrocíclicaso. Rev. vet. [online]. 2018, vol.29, n.1, pp.22-25. ISSN 1669-6840.  http://dx.doi.org/10.30972/vet.2912782.

A field study was carried out to determine the activity of an anthelmintic combination of derquantel (spiroindoles) plus abamectin (macrocyclic lactones) against Haemonchus sp in sheeps and goats. The clinical efficacy of the combination showed variable egg count reduction percentage dependent on the parasitic stages involved at the time of treatment and the previous status of resistance to the macrocyclic lactones. High efficacy (greater than 99%) was observed against oviposition of mature Haemonchus sp stages or when background of parasitic populations indicated moderate resistance to macrocyclic lactones. In contrast, lower efficiencies (76-83%) were observed when populations of this parasite showed severe resistance to macrocyclic lactones and immature stages constituted the majority of the parasitic population at time of treatment. Anthelmintic combinations could have an interesting potential for prevent o manage the nematode resistance in small ruminants, but the present observations emphasize the need to evaluate at the level of each establishment the activity of all anthelmintic drenches formulated with new or old drugs

Palabras clave : lambs; Haemonchus sp, derquantel; abamectin; efficacy.

        · resumen en Español     · texto en Español     · Español ( pdf )