Monepantel e levamisol no controle de helmintos gastrointestinais em rebanhos ovinos no Oeste de Santa Catarina.

The objective of this study was to evaluate the efficacy of monepantel and levamisole on gastrointestinal helminths in sheep herds in western Santa Catarina. The study was done in two stages. In the first one, five farms were selected and three groups (K, L and M) of 8 sheep each were formed. In the animals of group K, Monepantel (2.5 mg/kg) was administered, in those of group L, Levamisole (5.0 mg/kg) and the animals of group M were used as control (not medicated). The samples of feces were collected on day 0 and 10 of experiment, analyzed by the technique of McMaster with the objective of determining the number of eggs per gram of feces (HPG), followed by the technique of stool for the identification of the parasites. The second stage of the study was developed in a farm, where the same three groups were formed previously described with their respective treatments, and five days after the antiparasitic administration, feces sampling of these Animals for the performance of ecotoxicological tests, using Springtails (Folsomia candida) as a biological marker. To simulate the use of sheep feces as organic fertilizer, we define the doses 0; 2 4 and 8 tons of feces per hectare, as well as the survival and reproduction tests according to the ISO methodologies. The animals that received the treatment with Monepantel had reduction of the parasitic load (P < 0.05) compared with the remaining groups. In only one farm, the reduction of HPG was inferior (P < 0.05) in animals treated with levamisole compared to the control group. In the groups treated with Monepantel, resistance of Trichostrongylus spp was observed. At the same, and Haemonchus spp. It was resistant to levamisole on most farms. The efficacy of Monepantel for the five farms was 97, 98, 99, 100 and 100%, respectively, unlike the Levamisole, where they found efficiencies of 69,25, 52, 90 and 50%. The ecotoxicological tests show that there was no difference in the survival and reproduction of the collectors between the groups, ie the feces of animals medicated with levamisole and Monepantel does not affect F. candida. Therefore, the Monepantel, a relatively new antiparasitic product in the Brazilian market, can be the effective alternative in sheep farms with serious problems of resistance to anthelmintics, since it had desired efficacy in all the analyzed farms. [ABSTRACT FROM AUTHOR]