Effects of Intranasal Administration of Dex-Medetomidine and Ketamine on the Yellow-Bellied Slider (Trachemys scripta scripta)
1Zoological Medicine Residency, College of Veterinary Medicine, University of Georgia, Athens, GA, USA; 2Southeastern Wildlife Corporative, College of Veterinary Medicine, University of Georgia, Athens, GA, USA; 3Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, USA; 4Savannah River Ecology Laboratory, Aiken, SC, USA; 5Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA, USA; 6Department of Small Animal Medicine and Surgery (Zoological Medicine), University of Georgia, Athens, GA, USA
Abstract
Freshwater turtles are popular research, exhibit, and companion animals. As a result, there is an increasing need for chemical restraint methods for routine physical examination, biologic sample collection, and therapeutic procedures.2 However, anesthesia is often challenging because of their unique physiology, anatomy, and behavior. Intranasal anesthesia has been shown to be a reliable, effective, and easy method for the administration of anesthetic drugs in both human and veterinary medicine.1,3,4,5 In this pilot study, we evaluated the safety and utility of dexmedetomidine (M) and ketamine (K) and the reversal with atipamezole administered intranasally to Trachemys scripta scripta. Eight adult, free-ranging healthy turtles received 10 mg/kg of ketamine (100 mg/ml, Fort Dodge Animal Health, Fort Dodge, IA, USA) with 0.2 mg /kg of dexmedetomidine (0.5 mg/ml, Pfizer Animal Health, NY, NY, USA) intranasally with the use of a micropipette. Heart rate, respiratory rate, body temperature, and a sedation scores were all evaluated. A sedation score was assigned by determining the level of consciousness ranging from 0–5 (0 = fully conscious with no detectable effects, 1 = mild sedation, 2 = moderate sedation, 3 = heavy sedation, 4 = light anesthesia, 5 = surgical anesthesia). Blood was collected 45 min post-induction from both the subcarapacial sinus and dorsal tail vein, followed by a 2 mg/kg intranasal atipamezole (5 mg/ml, Pfizer Animal Health, NY, NY, USA) administration. Heart rate, respiratory rate, and cloacal temperatures remained stable throughout the entire procedure with no adverse effects. The mean time to a sedation score of 1 was 21±8 min. The median sedation score was 2, a level of anesthesia deep enough to perform a thorough physical exam and minor clinical procedures. At 45 min post-induction, ketamine and dexmedetomidine plasma levels were measured using a using liquid chromatography-tandem mass spectrometer at 1014.49±621.50 ng/ml/kg (K) and 17.28±8.57 ng/ml/kg (D) from the tail vein and 2390.63±2965.79 ng/ml/kg (K) and 24.59±23.93 ng/ml/kg (D) from the subcarapacial vein. After administration of atipamezole, turtles returned to pre-anesthetic activity in an average of 19±7 min. Results suggest that a combination of intranasal dexmedetomidine and ketamine should be considered as a reversible option for a moderate sedation for physical examination and blood collection in Trachemys turtles.
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