Dietary factors and aflatoxin toxicity: II. effect of fat source upon aflatoxicosis in rats

Previous studies in this laboratory have indicated that the tumorigenic and biochemical response of rats to aflatoxin may be affected by diet. To clarify the possible importance of the fat component of the diet in altering these biochemical responses a cross-over experiment was devised in which peanut oil and lard were reversed in two diets containing different protein sources and vitamin mixtures. It was found that more concentrated doses of aflatoxin administered for a shorter period of time had a more inhibitory effect upon growth, and liver pathology also appeared to be worse than when smaller doses were given for longer periods of time. There were slight differences in pathology due to the basal diet among peanut oilfed rats, and large differences when the fat component was lard. Plasma cholesterol levels were elevated as a result of the aflatoxin administration, regardless of the diet, and liver cholesterol levels were elevated in response to aflatoxin when diets containing the more varied protein source were fed. In all fractions of plasma fatty acids, fatty acid patterns similar to those observed in marginal essential fatty acid deficiency were seen when lard was fed. The observations that the more restricted protein diet or some component of it, reacts with lard to produce signs similar to those typical of essential fatty acid deficiency and that this regimen produces the most severe liver pathology further establishes the importance of the diet as a means of modifying the response of the organism to aflatoxin.