Efficacy of Different Anaesthetics on Depth of Anaesthesia and Hematological Parameters of Pigs

Abstract

Four groups of piglets were included in the experiment. In each of the experiments, we applied azaperone as the first premedication drug in the 2nd group 4 mg/kg body weight and in the other groups 5 mg/kg body weight. In experiment no. 1, we subsequently administered diazepam (1 mg/kg, i.m.) and ketamine (10 mg/kg, i.m.) to the piglets. In experiment no. 2, we applied xylazine (2 mg/kg, i.m.) and ketamine (20 mg/kg, i.m.). In experiment no. 3 we used diazepam (1 mg/kg, i.m.), xylazine (2 mg/kg, i.m.) and butorphanol (0.2 mg/kg, i.m.). In experiment no. 4, we administered xylazine (2 mg/kg, i.m.) and butorphanol (0.2 mg/kg, i.m.) to piglets. We applied the mentioned drug combinations intramuscularly in the area of ​​the neck muscles. Subsequently, in each of the experiments, we performed epidural anesthesia using 2% lidocaine, in a dose of 1 ml/40 cm of body length. After putting the animals under anesthesia, we recorded breathing and pulse frequencies, body temperature and checked reflex responses at time intervals. We performed a zero blood collection before the application of the first drug, the first collection after anesthesia and then a second collection the next day, in order to determine the hematological profile. From the conducted experiments, we assessed the relationship of the used combinations of substances to the course and depth of anesthesia and, according to the hematological profile, we evaluated the effect of these substances on specific hematological parameters. We recorded the longest duration of anesthesia in the first experiment when one of the piglets had disappeared pedal reflexes even after 90 minutes. On the contrary, the shortest anesthesia was during the third experiment, when all piglets reacted 60 minutes post-lidocaine. During experiments 1 and 3, we noticed a significant drop in body temperature compared to the reference values. In a short time interval after the lidocaine administration, the reflex of the pelvic limbs completely disappeared in all tested subjects in each of the experiments.  In experiment no. 3, at time 5 minutes post lidocaine administration, the nasal reflex and the reflex of the forelegs were also negative in all animals. In all tested subjects, 30 minutes after the epidural anesthesia was performed, we observed a negative reflex of the pelvic legs during the second and third trials. During experiment no. 3, we also observed a negative nasal reflex and a reflex of the front legs in the majority of the tested animals in the mentioned time interval.