Interaction of Vitamin A and Dieldrin on Mallard Liver Lipids and Biotin Content ,

Abstract

The effect of chronic ingestion of a low level of dieldrin (1 mg./kg. body weight) was studied on Mallards fed a diet either adequate or deficient in vitamin A. No gross symptoms of dieldrin toxicity were observed after twelve weeks on experimental diets. After five weeks marked foot pad keratinzation occurred in pesticide-fed ducks. Vitamin A deficient birds had significantly reduced liver weight when compared to the other treatment ducks. There was no effect of feeding pesticide on vitamin A content of the liver, but biotin per gram of liver was significantly (P <0.05) lower in the pesticide-fed ducks than in the nonpesticidefed birds.Liver fatty acid composition was altered either by pesticide ingestion or vitamin A deficiency. There were significant (P<0.05) accumulations of stearic and palmitic acids with a comparable reduction of their monoenoic derivatives in the dieldrin-fed ducks when vitamin A was adequate in the diet. There were higher levels of long chain polyunsaturated fatty acids (18:2, 18:3 and 20:4) in the dieldrin-fed birds when vitamin A was deficient.Ingestion of dieldrin at this level had a marked depressant effect on liver biotin content and altered fatty acid composition possibly by interference in enzyme systems involved in lipid metabolism.