Aflatoxin B₁, zearalenone and deoxynivalenol contamination in feedstuffs in Thailand

Abstract

Mycotoxin contamination of feedstuffs used in Thailand was studied by analyzing aflatoxin B1, zearalenone and deoxynivalenol in raw materials of feeds and complete feeds collected in 2000-2003 with TLC method. For raw material samples, 1, 373 imported and domestic samples of corn, soybean mill, peanut product, cassava and rice bran were examined, and for complete feed, 915 domestic samples were examined. The samples were extracted with acetonitril-water (84:16, v/v), and the extracts were then cleaned up with Mycosep 226 cleanup columns and developed on TLC with tolueneacetone (1:1, v/v). The plate was visually examined under ultraviolet light using pure standard toxins as references. For raw materials, the contamination level of aflatoxin B₁ higher than 20μg/kg was found in 24.02 %, 10.96 %, 5.68 % and 4.29 % of the samples collected in 2000, 2001, 2002 and 2003, respectively. The zearalenone level higher than 200 μg/kg was found in 8.11 %, 1.33 %, 6.18 % and 0.71 % in 2000, 2001, 2002 and 2003, respectively. The deoxynivalenol level higher than 1, 000 μg/kg was found in 7.50 %, 1.33 %, 0.83 % and 0 % in 2000, 2001, 2002 and 2003, respectively. The contamination in complete feeds was observed to change roughly from year to year in parallel with that in raw materials. The aflatoxin B1 level higher than 20 μg/kg was found in 14.29 %, 13.39 %, 7.53 % and 1.39 % in 2000, 2001, 2002 and 2003, respectively. The zearalenone level higher than 200μ/kg was found in 11.70 %, 1.79 %, 6.63 % and 1.39 % in 2000, 2001, 2002 and 2003, respectively. The deoxynivalenol level higher than 1, 000 μg/kg was found in 12.33 %, 1.79 %, 2.11 % and 0 % in 2000, 2001, 2002 and 2003, respectively.