Excretion of aflatoxin in a lactating cow

Abstract

After oral administration of a single dose (0·5 mg/kg) of mixed aflatoxins(B1, 44%; G1, 44%; B2, 2%) to a lactating cow, the excretion of fluorescent aflatoxin components was determined in the milk, urine and faeces over a period of 9 days. About 85% of the total aflatoxin detected in the milk and urine was excreted in the first 48 hr. None could be detected in the milk after 4 days and none in the urine and faeces after 6 days. Only 4·52% of the total dose of 300 mg was identified, the milk containing 0·18%, the urine 1·55% and the faeces 2·79%.Aflatoxin M1 was the only component found in the milk, the total being 0·35% of the amount of aflatoxin B1 ingested. M1 was also the major compound excreted in the urine, whereas aflatoxin B1 was the component present in greatest amount in the faeces. Aflatoxin G1 was excreted in both urine and faeces, the greater amount being found in the urine, but none was detected in the milk.A comparison of the pattern of excretion in the cow with that in the ewe showed that although the two were similar, there were some distinct differences, the chief one being a greater excretion of unchanged B1 in the cow than in the ewe.