ABSTRACT
Common blue-tongued skinks (Tiliqua scincoides) are popular pet reptiles; however, there has been limited research to investigate sedatives for this species. The purpose of this study was to measure the physiologic effects of four combinations of alfaxalone, dexmedetomidine, and midazolam for minor procedures such as intubation and blood collection. Eleven common blue-tongued skinks (Tiliqua scincoides) were used for this prospective, randomized cross-over study. The subcutaneous combinations were used as follows: 20 mg/kg alfaxalone (A); 10 mg/kg alfaxalone and 1 mg/kg midazolam (AM); 0.1 mg/kg dexmedetomidine and 1 mg/kg midazolam (DM); and 5 mg/kg alfaxalone, 0.05 mg/kg dexmedetomidine, and 0.5 mg/kg midazolam (ADM). Heart rate, respiratory rate, palpebral reflex, righting reflex, escape reflex, toe pinch withdrawal reflex, tongue flicking, and the possibility of intubation were recorded at baseline and every 5 min for 60 min. Venous blood gases were measured at baseline, full sedation, and recovery. Heart and respiratory rates decreased significantly in all groups, but the reductions were most prominent in DM and ADM. Analgesic effects, as measured by the toe pinch withdrawal reflex, were only observed in DM and ADM. Intubation was possible in all four protocols; however, it was not possible in two DM skinks. Based on these trials, ADM and AM are recommended for minor procedures in blue-tongue skinks.
ABSTRACT
INTRODUCTION: Tiliqua scincoides coexists with human activity and is frequently presented for rehabilitation due to injury. The correct identification of sex is important as animals identified as female should be subject to a different decision-making matrix for rehabilitation. However, identification of sex is notoriously difficult in Tiliqua scincoides. We describe a reliable, safe and cost-effective morphometry-based method. MATERIALS AND METHODS: Adult and sub-adult, wild Tiliqua scincoides dead on presentation or euthanased due to their presenting injuries were collected in South-East Queensland (SE Qld). Head-width to snout-vent length ratio (H:SV) and head-width to trunk length ratio (H:T) were measured and sex was defined at necropsy. Similar data were obtained from a previous study in Sydney, New South Wales (NSW). H:SV and H:T were assessed for accuracy of sex prediction by the area under the receiver operating characteristic curve (AUC-ROC). Optimal cut-points were identified. RESULTS: The AUC-ROC for the H:T test was for NSW adults, 0.99 (n = 29), NSW sub-adults, 0.95 (n = 10), Qld adults, 0.90 (n = 35) and Qld sub-adults, 0.79 (n = 25). In all cases, H:T was as good or superior to H:SV. H:T cut-points optimized for female sexing or both sexes ranged from 0.20 to 0.23 depending on State and adult status. Sensitivities and specificities of the test at suggested optimal cut-points ranged from 0.54 to 1.0. CONCLUSION: We describe how H:T can be used as an accurate method to determine sex in Tiliqua scincoides. However, it is more accurate in adults than sub-adults and more accurate in NSW skinks than in SE Qld skinks.
Subject(s)
Lizards , Male , Female , Humans , Animals , New South Wales , QueenslandABSTRACT
OBJECTIVE: To establish a repeatable, well-tolerated, non-invasive technique for sex identification in eastern blue-tongued lizards (Tiliqua scincoides). METHODS: Measurements were obtained from 69 free living eastern blue-tongued lizards presented for treatment that were either deceased on arrival or subsequently euthanased on welfare grounds. Weight, head width (H), snout vent length (SVL) and trunk length (T) were recorded. Ratios for head width to snout vent length (H/SVL%) and head width to trunk length (H/T%) were calculated. Sex was identified at necropsy. RESULTS: Evidence of sexual dimorphism in this population was shown. However, the degree of difference was subtle, requiring the use of ratios in order to refine the technique. Ratios of H/SVL% and H/T% showed significant predictability with respect to sex identification in both adult and sub-adult lizards. CONCLUSION: This study established a protocol for a repeatable, non-invasive technique for sex identification in the eastern blue-tongued lizard (Tiliqua scincoides) and provides a normal reference range.