RESUMEN
The aim of the present study was to evaluate the flukicide efficacy of the 2-amino-5(6)-chloro-1-methoxycarbonylbenzimidazole (II), named Fasciolinip-1, against eight and twelve-week old flukes in sheep. In a first experiment 35 young sheep were infected each with 300 metacercariae of Fasciola hepatica. Eight weeks postinfection five groups of seven animals each were treated as follows: Groups 1, 2 and 3 were given 2.5, 5 and 10 mg/kg of Fasciolinip-1. Groups 4 and 5 remained as non-treated and vehicle controls, respectively. In a second study, 32 sheep were infected each with 150 metacercariae. Twelve weeks postinfection, the animals were divided into 4 groups of 8 sheep each. Groups 1, 2 and 3 were treated orally with 5, 10 and 15 mg/kg of Fasciolinip-1, respectively. Group 4 remained as non-treated control. Fifteen days after treatment, all sheep from both experiments were killed to collect the flukes present in liver. Results indicated efficacies of 19.1%, 49.6% and 65.2% for groups 1, 2 and 3 of the first study and 48.3%, 64.8 and 90.6% for sheep of the second experiment, respectively. It was concluded that Fasciolinip-1 removed 8-week old flukes in limited numbers and 12-week old flukes in 90.6% when used at 15 mg/kg body weight.
Asunto(s)
Antihelmínticos/uso terapéutico , Bencimidazoles/uso terapéutico , Fasciola hepatica/efectos de los fármacos , Fascioliasis/veterinaria , Enfermedades de las Ovejas/tratamiento farmacológico , Animales , Antihelmínticos/farmacología , Bencimidazoles/farmacología , Conductos Biliares/parasitología , Evaluación Preclínica de Medicamentos/veterinaria , Fasciola hepatica/aislamiento & purificación , Fascioliasis/tratamiento farmacológico , Femenino , Hígado/parasitología , Masculino , Recuento de Huevos de Parásitos , Ovinos , Enfermedades de las Ovejas/parasitología , Resultado del TratamientoRESUMEN
A new in vitro test suitable for the large scale screening of chemical compounds for anthelmintic activity is described. The test which utilizes the fourth larval and adult stages of Nippostrongylus brasiliensis in a medium capable of supporting the growth and development of the parasite, detects selectively those compounds which possess either broad spectrum anthelmintic or specific anti-trichostrongyle activity. The screen is easy to operate requiring only minute quantities of experimental compound. It renders fully reproducible results which furthermore can be interpreted objectively. This is the first reported in vitro test directed against the parasitic stages of a nematode that is capable of detecting reliably the activity of a wide range of anthelmintics including thiophanate and all the benzimidazoles.