Naturally occurring ochratoxin A and mycobiota in raw materials and finished cattle feed

C.A.R. ROSA, K.M. KELLER, B.D. QUEIROZ, L.M. KELLER, J.M. RIBEIRO, L.R. CAVAGLIERI, M.L. GONZALEZ PEREYRA

Carlos Paz, Argentina

Congreso; Congreso MYCOGLOBE; 2006

Commercial feedstuffs in Brazil are an important component in modern animal husbandry but there is no information available about their fungal contamination and ochratoxin A (OTA) production. OTA producers  are present in raw materials used in production, cereals are considered the main resource of the intake of OTA metabolites.  The aims of this work were to: determine the mycoflora occurrence in raw materials and cattle feed and evaluate the OTA production. Likewise, the ability to produce OTA by several Aspergillus and Penicillium species was investigated. Samples were examined for total moulds, for Aspergillus and Penicillium spp occurrence and for their relative densities on dichloran rose bengal chloramphenicol and dichloran 18% glycerol media. The capacity to produce ochratoxin A by selected Aspergillus and Penicillium species was determined by HPLC. Total mould counts were generally higher than 1 x 104 CFU ml-1. Aspergillus and Penicillium species were isolated in the highest numbers. Aspergillus flavus and Penicillium citrinum were the most prevalent species. There was a high percentage of potential OTA producers (70%). The amount of OTA produced on this substrate was enough to cause adverse effects in animals. Several strains isolated from cattle feed were able to produce high levels of OTA on chloramphenicol yeast medium. OTA survey in raw materials, finished feed and storage practices must be investigated to determine their occurrence and to establish the livestock toxicological risk in cattle feed