Abstract

ACOSTA, María Eugenia; CAZORLA PERFETTI, Dalmiro; EDUARTE, Giovanny  and  MORALES MORENO, Pedro. Oral pathogenicity of an autochthonous isolate of the entomopathogenic fungus Beauveria bassiana in mice (Mus musculus, strain NMRI). Bol Mal Salud Amb [online]. 2012, vol.52, n.1, pp.79-86. ISSN 1690-4648.

This study evaluated concentrations of 1x10⁸ conidia/mL orally administered in white mice (NMRI strain, males and females), pathogenicity of a native isolate LF14 of Beauveria bassiana (Fungi: Ascomycota), highly virulent to Rhodnius prolixus and Triatoma maculata (Triatominae), vectors of Chagas disease in Venezuela. Clinical evaluations were done daily. Clearance of fungus in the faeces was estimated by direct examination and culturing, and infectivity by performing mycological and histopathological tests.Animals showed no discernible pathological changes or death and had 100% active-normal behaviour. In all the mice groups, including control ones, there was an increase in the mean weight gained through time, with statistically significance difference between the sexes (P<0,0000). Viable conidia were observed in faeces until 7 days after consuming the fungus. Anatomopathological changes or germinated conidia were not detected in analysed organs, with normal tissue reactions, suggesting no evidence for fungal multiplication. Results obtained allowed us to conclude that isolate LF14 B. bassiana orally administered is safe and non pathogenic in white mice (NMRI strain).

Keywords : Beauveria bassiana; pathogenicity; toxicity; mice; infectivity.