Comparison of 4 DifferentAnestheticProtocols in Common Marmosets{Callithrix jacchus)

For major invasive procedures in marmosets, such as section cesarean or insertion of telemetric devices into the abdomen, a long-acting, safe and reliable anesthesia is required including sufficientanalgesia.Limited data is availableon anesthetic protocolsin marmosets. Therefore, a crossover study to compare the head-to-head anesthetic effectsof four suitable protocols was
undertaken. Marmosets (n=10) received each of the 4 anesthetic protocols in random order on 4 occasions (days 28,56, 84,and 112). The 4 regimens included: (1)16 mg/kg alfaxalone i.m., (2) 16 mg/kg alfaxalone i.v., (3) lOmg/kg alphaxalone +0.1mg/kg medetomidine i.m., and (4) 1.5% isoflurane. Tooptimize the analgesic level of anesthesia, the protocols were combined
with opioids and NSAIDs, i.e. a single dose of each buprenorphine 20ug/kg i.m. and meloxicam 0.40mg/kg s.c. administered one hour prior to anesthetic induction. Induction, immobilization, and recovery times were recorded. During immobilization, cardiopulmonary parameters, muscle relaxation, reflex scores, and rectal temperature were recorded every 5 minutes. Quality of induction and recovery were scored on an ordinal scale. To determine possible local myotoxic effects of the used anesthetics blood samples were collected to determine aspartate aminotransferase, lactate dehydrogenase, and creatinine kinase levels in serum. Data with respect to induction, immobilization and recovery times, cardiopulmonary parameters, rectal temperature, and blood values during the different anesthetic protocols will be discussed.