Abstract:
This study was carried out in order to evaluate the analgesic, sedative, immobilizing and cardio-
pulmonary effects of medetomidine in goats after lumbosacral epidural injection of three (10, 20 and
30 mg/kg body weight) doses. The volume of the injection for all three medetomidine doses was 5 ml in
sterile water. Seventeen clinically healthy, Small East African goats of either sex and weighing between 12
and 22 kg (mean 2 SD; 14.8 2 2.5 kg body weight) were used. The animals were randomly assigned to
two groups. Seven goats were used for evaluating analgesic, behavioural and cardiopulmonary effects while
10 were used for experimental surgery. The cardiopulmonary values and rectal temperature were determined
and recorded at time 0 (preinjection) and at 5, 10, 15, 20 and 30 min, and thereafter at 15-min intervals up
to 180 min after injection. Analgesia of the flank and perineum was determined at time 0 (preinjection)
and at 5, 10, 15, 30, 60, 120 and 180 min using a scoring system. The spread of analgesia to the thorax,
neck, forelimbs and head was also determined and recorded. The onset and duration of lateral recumbency
was noted and recorded. Medetomidine at the given doses induced variable cardiopulmonary depression,
which was not detrimental to the animals. All three doses (10, 20 and 30 mg/kg) of medetomidine induced
adequate analgesia of the flank and perineum. Analgesia extended to the thorax, forelimbs, neck and head.
The duration of lateral recumbency was 136 and 166 min for the 20 and 30 mg/kg medetomidine doses,
respectively. The duration of lateral recumbency was not determined for the animal given 10 mg/kg
medetomidine. Signs of sedation (lowering of the head, drooping of the lower lip, partial to complete
closure of the eyes and salivation) were noted after administration of all three doses. It can be concluded
from this study that all three doses induced adequate analgesia of the flank and perineum. Surgical analgesia
of the flank of goats was achieved after lumbosacral epidural administration of 20 mg medetomidine/kg,
diluted in 5 ml of sterile water. Surgery was not performed with the other doses (10 and 30 mg/kg) of
medetomidine.
