Effects of 2 h anesthesia with halothane on blood cell counts and serum biochemical values in sheep and calves

To examine the clinical pathology of halothane in ruminants, five healthy fat-tailed sheep aged 1 to 2 years weighing 35 to 55 kg and four healthy calves aged 2 to 4 months weighing 30 to 65 kg were used. Anesthesia was induced and maintained by halothane using a closed-circuit anesthetic machine. The average induction time was found to be around 5 min in sheep and calves. Hematological studies indicated that there was an increase in neutrophils, significantly different only in sheep at 2 h after anesthesia, and a moderate decrease in lymphocytes. Total white blood cell counts slightly increased during anesthesia. Packed cell volume (PCV) was significantly higher 1 day and 1 week after anesthesia in sheep, but not in calves. The pre-anesthetic serum cholesterol level was around three times greater in calves compared to its level in sheep. However, there was a significant decline in the cholesterol concentration in sheep during 2 h anesthesia. Creatine phosphokinase (CPK) was moderately increased after 2 h anesthesia in both sheep and calves. Moreover, ALT, AST, and ALP were slightly increased 1 day post-anesthesia. Liver biopsies taken 2 weeks after anesthesia were not indicative of any specific pathologic change in sheep or calves. There were no prominent alterations in other biochemical parameters during or after anesthesia. Therefore, it is generally concluded that halothane can be used to induce and maintain general anesthesia in sheep and calves with the least adverse effects on clinical laboratory parameters.