A Zoletil (R)-Rompun (R) mixture as an alternative to the use of opioids for immobilization of feral red deer

Sixty chemical immobilizations of red deer (Cervus elaphus hippelaphus) hav e been carried out during an etho-ecological study from August 1994 to Dece mber 1996 in a 35 ha pen in the district of Nitra (Slovac Republic). Our ob jective was to determine the efficacy and standard dosages of Zoletil(R) an d Rompun(R) for the immobilization of adult red deer in feral conditions as an alternative to the use of the highly rode opioids. We therefore compare d an Immobilon(R)- Rompun(R) combination (ImRo) with a 1:1 mixture of Zolet il(R) and Rompun(R) (ZoRo) as an injectable solution. Use of both combinati ons led to the immobilization of >92% of deer with an injection volume <3 m l. Mean (SD) dose to achieve immobilization was 35 (14) <mu>g/kg ethorphine + 0.14 (0.056) mg/kg acepromazine + 0.36 (0.14) mg/kg xylazine compared to 1.2 (0.8) mg/kg tiletamine + 1.2 (0.8) mg/kg zolazepam + 2.3 (1.6) mg/kg x ylazine. This corresponds to a volume of 1.8 (0.7) ml/100 kg body mass (BM) for ImRo (range = 1.0 to 4.6) and to 2.3 (1.6) ml/100 kg BM for ZoRo (rang e = 0.7 to 4.0), respectively. Heart rate, respiratory rate and oxyhaemoglo bin saturation values did not differ significantly between the two groups d uring immobilization. Three deer (5%) died during immobilization, but fatal ities could not be directly associated with the drug effect. Mean (SD) time from darting to complete immobilization was 5.5 (4.2) min for ImRo and 7.5 (6.1) min for ZoRo, respectively. Differences were not statistically signi ficant. Anesthesia with both combinations of immobilizing agents could be r eversed within 2 min using sarmazenile-yohimbine for ZoRo and diprenorphine -yohimbine for ImXy immobilizations, respectively. We conclude that the 1:1 combination of Zoletil(R) and xylazine is a valuable alternative to the us e of opioids for the immobilization of adult red deer including feral adult animals.