Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Evaluation of three chemical immobilization protocols in golden-headed lion tamarins (Leontopithecus chrysomelas) undergoing vasectomy surgery.

Abstract

The Golden-headed lion tamarin, originally endemic to the southern Bahia region, was introduced in the state of Rio de Janeiro probably by illegal wildlife trade activity. The species is currently found in one of the remaining areas of natural occupation of the golden lion tamarin (Leontopithecus rosalia), which may compromise the survival of the latter. In order to mitigate this problem, an action plan was elaborated and the capture of golden-headed lion tamarins recommended. Both capture and chemical restraint procedures can cause stress and compromise homeostasis with a direct effect on the health and well-being of the animals. Besides that, current chemical immobilization protocols usually result in prolonged recovery times. This study aims to determine and compare the cardiovascular and respiratory effects of three different protocols for chemical immobilization of golden-headed lion tamarins. Thirty-five adult male specimens of Leontopithecus chrysomelas were studied. Animals were randomly separated into three groups: ketamine S(+) and midazolam (15 mg kg-1 and 0.5 mg kg-1) (KSM group), ketamine S(+) and dexmedetomidine (15 mg kg-1 and 10 µg kg-1) (KSD group) and racemic ketamine and dexmedetomidine (15 mg kg-1 and 10 µg kg-1) (KD group). Periods of latency, immobilization and recovery were evaluated. Heart rate and rhythm, respiratory rate, peripheral oxyhemoglobin saturation, systolic blood pressure, rectal temperature, induction and recovery quality, sedation, antinociception, and degree of muscle relaxation were monitored every five minutes for 50 minutes. Parametric data were analyzed by using repeated measures analysis of variance (ANOVA) followed by a Tukey's test. Non-parametric data were analyzed by the Kruskal-Wallis test followed by Dunn's test. Values of P<0.05 were considered statistically significant. No significant differences were found in respiratory rate, peripheral oxygen saturation, temperature, systolic blood pressure, onset of muscle tone loss, latency and partial and total recovery periods. Heart rate, sedation and muscle relaxation degrees, antinociception, and lidocaine consumption presented significant difference at the same moments between KSM and KSD and between KSM and KD. Marked bradycardia was presented on KSD and KD groups, with values remaining within the normal range. This study demonstrated that combinations of dexmedetomidine with racemic ketamine and S(+) ketamine presents the best outcomes for muscle relaxation, sedation and antinociception and were safe for vasectomy surgery in golden-headed lion tamarins.