Responses of Dairy Calves to Oral Doses of Aflatoxin

Abstract

Seven pairs of young male dairy calves received daily oral doses of aflatoxin from 0 to .10 mg/kg body weight for 6 weeks of pretreatment and 6 weeks of aflatoxin dosing. Analysis was by least squares analysis of variance. Differences (P<.01) for dose and dose×period interaction were shown for a reduction of feed intake, weekly gain, serum carotene, and for an increase fo serum alkaline phosphatase. Differences (P<.01) for dose×period interaction were also shown for an increase of total bilirubin and a decrease of serum inorganic phosphorus. Serum vitamin A was decreased (P<.05) by dosing with a (P<.05) dose×period interaction. Most of these aflatoxin-induced effects occurred by the second week of treatment and at .08 and .10mg doses.At postmortem livers appeared lights tan to orange and gall bladders were enlarged to 10 times normal. Liver tissue showed bile duet proliferation, dilated intralobular lymphatic duets, perivascular edema, and edema around the nect of the gall bladders was evident. Histochemical determination of alkaline phosphatase was not indicative of hepatic cell damage or obstructive jaundice. At aflatoxin doses .08 and .10mg, glycogen deposits appeared only in regenerating liver cells. Responses of young male dairy calves to aflatoxin contaminated feed and oral doses of erude toxin are similar.