Abstract
ABSTRACT. Landa M.F., González Pereyra M.L., Pena G., Bagnis G., Cavaglieri L.R., Rosa C.A.R. & Dalcero A.M. Chronic exposure to aflatoxigenic fungi related to liver damage in pelt chinchillas (Chinchilla lanigera). [Exposição crônica a fungos produtores de aflatoxinas relacionada a danos hepáticos em chinchilas (Chinchilla lanigera) de pele]. Revista Brasileira de Medicina Veterinária, 34(4):303-310, 2012. Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta N 36 Km 601 (5800), Río Cuarto, Córdoba, Argentina. E.mail: adalcero@exa.unrc.edu.ar Chinchilla pelt is a rare and expensive fur. Therefore, breeding these animals is a profitable activity. Confirmed acute cases of aflatoxin intoxication have been reported in Argentinean farms. The aims of this study were i) to evaluate mycobiota and AFB1- -producing species in chinchilla feeds ii) to investigate their natural AFB1 contamination and iii) to analyze histopathological lesions in chinchilla livers. Feed samples (A: fur, B: mother, C: lucerne cubes) were collected from a factory and a farm. Livers of sacrificed chinchilla from the farm were macroscopically and microscopically examined. Total fungal counts of feed C exceeded 1x104 CFU/g. Aspergillus, Fusarium and Penicillium were the prevalent genera, while A. flavus, A. fumigatus, F. verticillioides and F. proliferatum were the prevalent species. Fifty % of A. flavus strains from factory samples and 69.7% from farm samples were able to produce 2.78 to 8.64µg/g and 0.66 to 58.8µg/g AFB1, respectively. Aflatoxin B1 was detected only in feeds from the farm, finding the highest incidence in feed C. Toxin levels varied between 1.90 and 97.34 µg/ kg AFB1 . Mean levels in feed A and C exceeded 20 µg/kg. Macroscopic examination of livers revealed normal appearance, size and color. However, histopathological examination indicated 63.3% showed slight to moderate lipid degeneration with diffuse cytoplasm vacuolation, 9% intense lipid cytoplasm vacuolation and 27.3% hydropic degeneration and nuclear vacuolation in hepatocytes. A periodic monitoring of aflatoxins in feeds and their ingredients can prevent acute outbreaks and economic losses caused by chronic exposure.