[Contamination of cow's milk during ingestion of small quantities of aflatoxin]

Sixteen cows, some in the early and the rest in the late lactation period, were given daily, during a eight day period a ration of peanut meal naturally contaminated by aflatoxin. The analysis for aflatoxin M1 of the milk obtained from these cows indicates the following points: --the level of aflatoxin M1 is not influenced by the volume of the daily milk secretion; --the quantity of this hydroxy-derivative expressed as a percentage of the parent toxin varies from 0.14 to 0.34 in the animals in the late lactation period, and from 0.66 to 0.95 in the cows producing some twenty litres of milk per day; --in order to achieve a tolerance limit of 20 ng/kg of aflatoxin M1, in the milk, the daily ingestion of the mycotoxin by cows should not exceed 90--100 micrograms per animal.