Reversal of ethionine intoxication in the domestic fowl with methionine and adenine sulphate

Amelioration of ethionine toxicity in the chick

Several chick bioassays were conducted to evaluate means of ameliorating ethionine toxicity. Supplementing a corn-soy diet marginally deficient in sulfur amino acids (methionine + cystine) with .075% D,L-ethionine reduced weight gain in 8-day-old chicks by 70% compared to gains of unsupplemented controls. Dietary addition of .50% DL-methionine prevented reduction in weight gain and feed intake resulting from ethionine supplementation whereas feeding supplemental L-cystine was without effect. Supplementation of the ethionine-containing diet with either choline or betaine ameliorated the growth depression, although neither compound was able to completely overcome the toxic effects of ethionine. Dietary ethionine did not affect plasma levels of free methionine or cystine but did increase plasma free glycine 6-fold. Dietary addition of .50% DL-methionine caused normalization of plasma glycine levels whereas it elevated plasma methionine concentration. Although results suggested the possibility of ethionine-induced serine or threonine deficiency, dietary additions of .75% L-serine or .75% L-threonine failed to improve chick weight gain. These studies suggest that ethionine, in addition to affecting transsulfuration and transmethylation activity may exert specific effects on certain amino acids in tissue pools.

Effect of dietary DL-ethionine on growth and liver metabolism

The effects of DL-ethionine, given in the diet or by injection, on growth, hepatic glycogen and lipids, and the activities of some cytoplasmic NAD-linked dehydrogenases and NADPH-producing enzymes were investigated. 2. Growth virtually ceased after feeding ethionine for 2 d. 3. Ethionine induced an accumulation of lipid, decreased the activities of malic enzyme and isocitrate dehydrogenase and increased the activity of lactate dehydrogenase. 4. The concentration of glycogen in the liver of ethionine-fed chickens increased for 3 d in spite of a decrease in food intake, but then decreased.