Antinociceptive and selected physiological effects of morphine and xylazine on tiletamine-zolazepam anesthesia in llamas

The combination of morphine (0.5 mg kg−1) and xylazine (0.15 mg kg−1) increased the duration of antinociception compared with xylazine alone, in TZ-anesthetized llamas. Treatments X, M and MX were associated with hypoxemia (PaO2 < 60 mmHg).