This work was conducted in order to study the kinetic behaviour of dietary aflatoxins in the colostrum of a pregnant cow exposed to contaminated feeds for a short period. In this study, two pregnant cows received a single dose of dietary aflatoxins in the form of rice powder contained 31.20 ppm aflatoxin B and 19.68 ppm aflatoxin G during the last stage of pregnancy, at about two weeks before parturition. Samples of colostrum were collected from dams and assayed for the presence of toxic metabolites as well as its conjugations by electrophoretic analysis. The results revealed that the intake of aflatoxins appeared in the colostrum postpartum as AFM1 and also AFB2a which is a non toxic metabolite. Moreover, it was found that the excreted metabolites including AFB2a were conjugated to the immunoglobulin protein fraction of the colostrum. The significance of the obtained results to the newborn calf are discussed.