Resistência de Cooperia spp. e Haemonchus spp. às avermectinas em bovinos de corte / Resistance of Cooperia spp. and Haemonchus spp. to avermectins in beef cattle

RESUMO

Foram realizados dois testes de redução de ovos de helmintos por grama de fezes em bovinos naturalmente infectados. No primeiro teste utilizaram-se quatro grupos tratados ivermectina 1% (IVM), produto endectocida experimental (PEE), ivermectina LA 1% (IVMLA) e doramectina 1% (DRM). A contagem de ovos por gramas de fezes (OPG) foi realizada durante 14 dias pós-tratamento. Foram observadas as seguintes taxas de eficácia IVM, -1,3%; PEE, 100%; IVMLA, 18,9% e DRM 50,6%. Os gêneros de helmintos encontrados foram Cooperia e Haemonchus. No segundo teste foram avaliadas moxidectina 1% e abamectina 1%, e ambas apresentaram eficácia acima de 99%.(AU)

ABSTRACT

Two fecal count-reducing-tests in infected bovines were performed considering eggs per gram. In the first test it was used four treated groups with ivermectin 1% (IVM), experimental endectocid product (EEP), ivermectin LA 1% (IVMLA) e doramectin 1% (DRM). Evaluating the finds of eggs per gram in a 14-day-period after treatment and comparing with the control group it was observed the following efficacy rates 1.3% to IVM, 100.0% to EEP, 18.9% to IVMLA and 50.6% to DRM. Helminthes genders found were Cooperia and Haemonchus. The second test was performed to evaluate moxidectin 1% and abamectin 1% and results showed efficacy over 99.0% for both.(AU)