Prevalence of Aspergillus species on selected Colombian animal feedstuffs and ability of Aspergillus section Flavi to produce aflatoxins.

A total of 57 samples of feedstuffs commonly used for animal nutrition in Colombia (maize, soybean, sorghum, cottonseed meal, sunflower seed meal, wheat middlings and rice) were analysed for Aspergillus contamination. Aspergillus fungi were identified at species level and their ability to produce aflatoxins was determined by highperformance liquid chromatography. A total of 31 of the feedstuffs analysed (54.4%) were found to contain Aspergillus spp. The most contaminated substrate was maize (100%) followed by cottonseed meal (80%), sorghum (60%) and wheat middlings (60%). Soybean showed lower levels of contamination (10%). No Aspergillus spp. could be isolated from rice or sunflower seed meal. Total Aspergillus strains isolated were 50, with 28 belonging to section Flavi (56%), 17 to section Nigri (34%), 4 to section Circumdati (8%) and 1 to section Fumigati (2%). Among section Flavi, 17 isolates were identified as A. flavus, seven as A. parasiticus, two as A. oryzae and two as A. tamarii. Production of a...