Avaliação da patogenicidade in vitro de Beauveria bassiana sobre estágios imaturos de helmintos gastrointestinais de caprinos

Abstract

The scenario of Brazilian national livestock has been growing significantly and goat farming, standing out each year, but attention to the care of goat breeding is essential, as regards nutrition, health and ambience. Among the major problems experienced in these properties is the antihelmintic resistance caused by the indiscriminate use of drugs without specialized technical assistance, this competes with the provision of sub or overdoses routinely using the same active principle in this applicability without prior knowledge and has been causing the resistance. of the helminths that parasitize them. Given the need for the market to have a herd of quality, without major economic losses, seeking to meet the consumer market and its requirements, the search for new alternatives to control these parasites increased significantly, aiming at the replacement of allopathy by less artificial means, thus being Biological control has become a viable option as a resolution of this aggravating factor. Thus, the objective of the present study was to evaluate the in vitro pathogenicity of the fungus Beauveria bassiana on the immature stages of goat gastrointestinal helminths. The work was carried out at the Campus of the Federal University of Recôncavo da Bahia, located in Cruz das Almas - BA. The tests were performed at the Parasitology and Parasitic Diseases Laboratory (LPDP) of the University Hospital of Veterinary Medicine (HUMV) of UFRB. The experiment consisted of three groups, one control composed of sterile distilled water solution and 0.01% Tween 80 and two treatments with aqueous B. Bassiana formulations at concentrations: 1.0 x 107 conidia / mL and 1.0 x 108 conidia / mL; Each group consisted of six experimental units. To evaluate the effect of B. Bassiana on the nematodes, the quantitative co-culture technique was performed using two grams of feces containing Trichostrongylid eggs, 2 grams of sawdust and 2ml of the above treatments. After 7 days of cultivation, the larvae were quantified and it can be observed that the fungus B. Bassiana was able to significantly reduce the number of helminths in both concentrations 107 and 108 conidia / mL when compared to the control group. It is concluded that B. Bassiana is pathogenic for immature stages of goat gastrointestinal helminths, and that the concentration of 108 conidia / mL is the most indicated, since it promoted less larval recovery. However, there is a need for further studies to support its applicability in the field.