Furazolidone-induced congestive cardiomyopathy in ducklings: regression of cardiac lesions after cessation of furazolidone ingestion.

Newly hatched male White Pekin ducklings (n = 92) were allotted to 2 groups of 46 each and fed 750 mg of furazolidone (FZ)/kg of feed either for 8 weeks (group 1) or for 4 weeks followed by 4 weeks of no FZ intake (group 2). Regression of FZ-induced toxicosis was observed in ducklings of group 2 after cessation of FZ consumption, as evidenced by decreased mortality, progressive decrease in ascites, and increases in body weight gains. Necropsy of 8-week survivors revealed decreased frequency and severity of ascites in ducklings of group 2. The severity of FZ-induced cardiac alterations also was diminished, with a decrease in left ventricular dilatation score and an increase in absolute heart weights in 8-week survivors in group 2. Further evidence of regression of FZ-induced congestive cardiomyopathy after cessation of FZ ingestion was gained from development of intermediate cardiac damage severity scores and frequency and severity of ascites at necropsy in ducklings (previously studied) examined after 4 weeks of FZ feeding, compared with those found in group 1 (FZ 8 weeks) or in group 2 (FZ 4 weeks, no FZ 4 weeks) of the present study. Furazolidone-induced cardiac disease in ducklings offers an attractive model for studies of the pathogenesis of congestive cardiomyopathy and cardiac failure.