Postmortal degradation of furazolidone and furaltadone in edible tissues of calves.

Rapid and complete postmortal degradation of furazolidone and furaltadone occurred in liver, kidney and muscle tissues of veal calves. Different degradation half-lives were observed between these tissues, the mean ranging from less than 7 minutes to 63 minutes. At 24 h after slaughter the parent nitrofurans were no longer detectable in edible tissues. For residue monitoring purposes plasma and/or urine can be used, if these matrices are treated in a specific way immediately after slaughter; muscle tissues and organs are unsuitable for residue monitoring of parent nitrofurans.