The use of analgesics by epidural and subcutaneous way in bitches submitted to surgical sterilization by laparotomy was evaluated. Twenty females dogs of different ages and breeds were sedated and anesthetized with a combination of tiletamine-zolazepam and randomly distributed into four experimental groups of five animals each. Through the epidural space, the animals of each group received 0.1mg/kg of morphine (MG) or 0.2mg/kg of xylazine (XG); while the control group (CG) received a 0.9% solution of chloride sodium. The final volume stabilished for lumbosacral epidural injections was 0.3mL/kg. The dogs of meloxicam group (MEG) subcutaneously received 0.2mg/kg of the drug. The initial measurement of plasmatic cortisol concentration, heart and respiratory rates, and behaviour parameters were evaluated as soon as the surgical procedure had finished (M1). These evaluations were repeated after 2, 6, 12, and 24 hours of the post-operative period (M2, M3, M4, and M5 respectively). The behaviour parameters were evaluated by clinical signs and respective scores. Values of cortisol concentration were higher in the xylazine group than the ones registered in the morphine group. Meloxicam failed to provide pain control. Epidural use of morphine guaranteed fewer side effects and better pain control.
dog; opioids; alfa-2-agonists; meloxicam
