[Determination of aflatoxins and toxicogenic fungi in mixed feed for poultry].

The presence of aflatoxins was determined in 155 samples of chicken feeds, as well as their fungal contamination. Aflatoxins were detected in 3 of the analized samples; one of them contained 1620 micrograms/kg, a highly dangerous amount for chickens. The amount found in the remaining 2 samples was 30 micrograms/kg. A study of toxigenic fungus showed a prevalence of 69.3% of Aspergillus flovus: 72.4% of this percentage corresponded to aflatoxins producing strains. The prevalence of Aspergillus ocraceus was 18.6%; ten per cent of it corresponded to ochratoxin A producing strains. Chicken feeds are an adequate substratum for the formation of aflatoxins; this was demonstrated by raising the humidity contents of initially negative samples, which contained toxigenic Aspergillus flavus spores. The danger of storing chicken feeds under certain humidity and temperature conditions was demonstrated.