THE INFLUENCE OF IONOPHORES ON THE DURATION OF XYLAZINE-KETAMINE ANESTHEISA AND THE HEPATIC CYTOCHROME-P-450 CONTENT OF BROILER-CHICKENS

This study examined the effects of feeding monensin, lasalocid or sali nomycin (at 1x and 2x therapeutic levels for 20 d) on the duration of xylazine+ketamine sleep time and the hepatic cytochrome P-450 content in broiler chickens of different age groups (3- and 6-w-old). The 3-w- old birds fed 120 ppm salinomycin had a reduced xylazine+ketamine slee p time as compared to control (no drug). The 6-w birds had a sleep tim e similar to the controls. Associated with ionophore feeding was a tre nd toward P-450 induction when compared to controls. Increased P-450 c ontent was statistically significant-in the 3-w birds fed 90 ppm lasal ocid and in the 6-w birds fed 200 ppm monensin. lonophore administrati on above recommended levels gave conflicting results for duration of x ylazine+ketamine sleep time and hepatic cytochrome P-450 levels. The i sozymes of cytochrome P-450 responsible for xylazine and ketamine meta bolism may be different from those induced by the ionophores. There wa s no significant age-related difference in ionophore effects on cytoch rome P-450 content.