Evaluation of different dose rate combinations of ketamine, romifidine and azaperone for castration of 3-4 and 5-6 weeks old piglets.

INTRODUCTION: In this study dose rate combinations of ketamine, azaperone and romifidine were tested in 3-4 (G3-4) and 5-6 weeks (G5-6) old piglets according to a dose rate decision tree (DRT) to provide calm anaesthesia induction, reaction-free anaesthesia for castration and smooth recovery within 2 hours. When a combination failed to meet those criteria in 2 piglets, the next dosage of the DRT was tested. In G3-4 four combinations were tested in 14 piglets with dose rates of 10-20 mg/kg ketamine, 3 mg/kg azaperone and 0.15-0.20 mg/kg romifidine IM. Induction was smooth in all piglets, but depth of anaesthesia or recovery (11 and 6 piglets) were insufficient. In G5-6 five combinations were tested in 37 piglets with dose rates of 10-20 mg/kg ketamine, 3-4 mg/kg azaperone and 0.15-0.20 mg/kg romifidine IM. Induction was smooth in all piglets but 2. Depth of anaesthesia or recovery (17 and 7 piglets, respectively) were insufficient. In the present study with 3-4 and 5-6 weeks old piglets, acceptable quality of anaesthesia could not be achieved despite using high drug dose rates.