Search

There is limited knowledge on amphibian sedation, and drug doses appear to be species-specific and affected by the administration route. Alfaxalone, a neuroactive steroid, has gained popularity in veterinary medicine and has been evaluated in some amphibian species. Previous studies in amphibians have demonstrated a sedative dose range of 10–30 mg/kg IM. No peer--reviewed publication has investigated this drug in Sonoran Desert toads (Incilius alvarius) specifically. Therefore, the purposes of this study were 1) to determine the effective dose 50 (ED50) of IM alfaxalone for sedation, and 2) to determine the cardiopulmonary effects of the effective dose 99 (ED99) in 13 Sonoran Desert toads. Using Dixon's up-and-down method, the ED50 was calculated as 9.02 mg/kg, and using a nonlinear regression, the calculated ED50 was 9.65 mg/kg, and the ED99 was 9.91 mg/kg. Based on these results, 10 mg/kg IM was administered, and its cardiovascular effects were determined for 120 min postinjection. The 10 mg/kg IM dose resulted in significant transient cardiorespiratory depression in all toads, with most toads (11/13) showing signs of sedation (recumbency and/or loss of righting reflex) within 30–40 min postinjection. There was no associated mortality with this study, and the side effects associated with this dosage (cardiorespiratory depression, ventral erythema, and dysphoric behavior such as rolling and head pressing) resolved in all toads prior to the end of the 120 min observation window. This study hopes to increase the understanding of the clinical application and limitations of this drug for sedation of Sonoran Desert toads. [ABSTRACT FROM AUTHOR]

A 6-yr-old captive-bred male black pine snake (Pituophis melanoleucus lodingi) weighing 0.49 kg with a snout-to-vent length of 127 cm was presented for evaluation of a caudal coelomic swelling that had been present for 3 days. Survey radiographs showed focal distention of the body wall with a mass of soft tissue and mineral opacity. Anti-inflammatory and empiric antibiotic treatments were initiated, with no significant improvement. Coelomic ultrasound showed effusion and intestinal changes consistent with an intussusception. On exploratory celiotomy, the mass was found to be a 10-cm-long colonic diverticulum. A colotomy was performed and inspissated fecal material was removed from the lumen of the diverticulum prior to its resection and closing of the bowel defect. Histological examination of the excised tissue was consistent with an intestinal diverticulum and complete absence of the smooth muscle layers, indicating nonperforating rupture of the bowel wall. The snake recovered uneventfully and began eating 5 days after surgery. On physical and ultrasound examinations 8 months after surgery, the snake's body condition had improved and there was no recurrence of clinical signs, with the snake remaining normal 30 months postsurgery at home. [ABSTRACT FROM AUTHOR]

The objective of this study was to compare the physiologic and anesthetic effects, and differences, between two intramuscular drug protocols in adult bullsnakes (Pituophis catenifer sayi); the bullsnakes were being anesthetized for a radiotelemetry study. Free-ranging bullsnakes were injected IM with 10 mg/kg butorphanol, followed by either 20 mg/kg alfaxalone or a combination of 0.5 mg/kg midazolam, 0.05 mg/kg dexmedetomidine, and 5 mg/kg ketamine (MDK). After administration, muscle tone, response to stimuli, and jaw tone were evaluated before endotracheal intubation and surgical stimulation to implant coelomic transmitters. If a bullsnake responded to stimulation induced by surgical preparation, or noxious stimuli induced by the surgical procedure, isoflurane was administered to maintain a surgical plane of anesthesia. Heart rate, sedation depth, esophageal temperature, end-tidal CO2, respirations, time to spontaneous ventilation, extubation, return of righting reflex, and return of spontaneous movement were recorded. Assisted ventilation was initiated if bradypnea (<2 breaths/min) or apnea occurred. Six bullsnakes were evaluated in each group, for a total of 12 bullsnakes. The MDK group was reversed with 0.5 mg/kg atipamezole and 0.02 mg/kg flumazenil IM. All alfaxalone-treated bullsnakes responded to surgical stimulation with movement and required anesthetic maintenance with isoflurane, whereas none of the MDK bullsnakes required inhalant anesthesia. Bullsnakes anesthetized with MDK recovered significantly faster after reversal than bullsnakes in the alfaxalone group. MDK produced a satisfactory level of anesthesia for a minor surgical procedure in bullsnakes, whereas alfaxalone did not. Additional injectable (beyond butorphanol) or inhalant anesthetic agents are recommended for surgical procedures when using alfaxalone. [ABSTRACT FROM AUTHOR]