A mycological and bacteriological survey on feed ingredients and mixed poultry feeds in Reunion island

Abstract

A survey was carried out in Reunion island to obtain data on the occurrence of fungi, aflatoxigenic strains of Aspergillus flavus, aflatoxins, total aerobic bacteria and salmonellae of 150 samples of mixed poultry feeds and raw materials. These were collected at five farms over a 3-month period during the warm rainy season. White corn and Braizlian soybean meal seemed to present a better microbiological quality than yellow corn and US soybean meal. Mixed poultry feeds presented a high total mold count reflecting the mold flora of raw materials. The most frequent and abundant fungi were Aspergillus flavus. A. glaucus group, Fusarium spp., Penicillium spp., A. candidus, Mucor spp., A. restrictus, Scopulariopsis spp., Cladosporium spp. and A. versicolor. Of the 118 A. flavus strains screened, 42 (35.6%) were aflatoxigenic. Yellow corn samples were the most frequently contaminated with aflatoxigenic strains (54.5%), followed by mixed feeds (44%). Of the 66 samples tested, 24 (36%) contained aflatoxins (traces to 22 ng/g). A good correlation seemed to exist between presence of at least one aflatoxigenic strain per sample and presence of aflatoxins.