Natural occurrence of zeralenone in feeds and feedstuffs used in poultry and pig nutrition in colombia.

A total of 200 samples of feedstuffs and mixed feeds used for poultry and pig nutrition in Colombia were analysed for zearalenone using a LC technique with a limit of detection of 20 μg/kg. Samples of grain sorghum, maize, processed soybean, rice meal, cottonseed meal, and poultry and pig feeds, representative of the Colombian production for the 1995-1996 harvest, were taken at feed manufacturing plants located in different cities of the country. Zearalenone was detected in 25 of 45 samples of sorghum, 2 of 33 samples of maize, 7 of 22 samples of rice meal, 9 of 17 samples of cottonseed meal, 11 of 30 samples of poultry feed and 6 of 16 samples of pig feed. Zearalenone was not detected in soybean or other feedstuff s analysed (wheat by- products, cassava meal, palm). Overall levels of zearalenone ranged from 29 to 3956 μg/kg, with a mean value of 436 μg/kg. Only one of the 6 positive samples of pig feed had a zearalenone concentration above 500 μg/kg, which is normally considered as the safe level for pigs.