Intermediary metabolism of 2,6-dichlorobenzonitrile (dichlobenil) in chickens and growth of chickens fed dichlobenil.

1. Ten 14C-labelled metabolites were isolated from either bile (6 metabolites) or urine (7 metabolites) from chickens given single oral doses of 2,6-dichlorobenzo[14C]nitrile (14C-dichlobenil). All metabolites were benzonitriles with the following ring substituents: two Cl, OH (two isomers); Cl, two OH; Cl, OH, SH; Cl, OH, S-glutathione; Cl, OH, S-cysteinylglycine; Cl, OH, S-cysteine; and Cl, OH, S-(N-acetyl)cysteine. 2. 2-(S-Glutathionyl)-3-hydroxy-6-chlorobenzo[14C]nitrile perfused through chicken kidneys in situ was excreted in urine from the perfused kidney (44% dose) as 2-mercapto-3-hydroxy-6-chlorobenzonitrile. 3. Dichlobenil (2,6-dichlorobenzonitrile) was fed at 0, 75, 150 or 225 p.p.m. in the diet to broiler and laying strains of cockerels to determine biological activity. Feed consumption and growth were not affected, but liver and kidney weights were higher in chicks fed the dichlobenil. The percentage of lipid or nitrogen in the livers and kidneys from chicks fed dichlobenil did not differ from controls and histological or ultrastructural changes were not observed in these tissues.