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The objective of this study was to evaluate the effects of tiletamine–zolazepam as a sedative drug in central bearded dragons (Pogona vitticeps) and determine if efficacy differed based on administration route. Ten healthy, adult central bearded dragons received tiletamine–zolazepam (20 mg/kg) either intramuscularly (IM) or subcutaneously (SC) in the cranial body in a randomized, blinded, complete crossover study with a minimum washout period of 2 wk between treatments. Respiratory rate, heart rate, body position, response to restraint, spontaneous movement, righting reflex, and jaw tone were evaluated. All bearded dragons received flumazenil (0.05 mg/kg, SC) in the cranial body 45 min after the initial tiletamine–zolazepam injection. Righting reflex was lost in all bearded dragons receiving tiletamine–zolazepam IM, but only half of the animals lost righting reflex after SC injection. Jaw tone was lost in 90% (9/10) of animals receiving IM injections compared to 40% (4/10) following SC injections. Recovery from sedation was similar between route of administration (IM: 69 ± 39 min, SC: 57 ± 33 min, P= 0.43). Postsedation food intake was suppressed 2 h after return of righting reflex. Based on the findings of this study, IM administration of tiletamine–zolazepam results in a deeper and more consistent plane of sedation in bearded dragons when compared to the SC route. Prolonged recoveries were noted with both routes of administration. [ABSTRACT FROM AUTHOR]

Combinations of midazolam and butorphanol are commonly used in avian sedation protocols but no studies have been performed in Columbiformes. Minimizing intramuscular drug injection volumes is desirable, in order to reduce the potential for injection-induced discomfort. Reduction of drug injection volumes can be achieved by using higher concentrated drug formulations. The goals of this study were to evaluate a midazolam-butorphanol sedation protocol in domestic pigeons and to evaluate if a difference in total drug injection volume has an effect on sedation parameters in this species. Twelve adult pigeons were sedated with butorphanol (2 mg/kg) combined with 4 mg/kg of midazolam as either a standard (5 mg/mL) or concentrated (50 mg/mL) formulation, intramuscularly, in a randomized, blinded, complete cross-over study. Various parameters were used to assess for differences in sedation onset, depth, and recovery. Flumazenil (0.05 mg/kg) was administered intramuscularly for reversal of midazolam 30 minutes after sedative administration. The sedation protocol resulted in moderate sedation and all birds became sternally recumbent, while 4of 12 birds lost righting reflex. Recovery was rapid in all birds following administration of flumazenil and no adverse reactions were observed. Significant differences in drug injection volumes had no clinically relevant effects on sedation parameters. Use of concentrated midazolam resulted in ∼3.5 times smaller total injection volumes, while achieving the same efficacy as standard concentration of midazolam. The reduced injection volumes are desirable from an animal welfare standpoint, as they may reduce the risk of local discomfort associated with intramuscular injections. [ABSTRACT FROM AUTHOR]

African pygmy hedgehogs (Atelerix albiventris) are popular zoological companion animals that routinely require chemical immobilization for veterinary care. The objective of this randomized, blinded, cross-over study was to evaluate the efficacy of low and high dosages of subcutaneous (SC) tiletamine-zolazepam for sedation and the efficacy of flumazenil for recovery in African pygmy hedgehogs. Twelve adult hedgehogs (7 males, 5 females) were administered tiletamine-zolazepam at 10 mg/kg (T10) or 30 mg/kg (T30) SC. Physiologic variables, reflexes and behaviors were monitored to evaluate quality of immobilization. Forty-five minutes after tiletamine-zolazepam injection, hedgehogs were administered flumazenil or an equivalent volume of saline SC. Baseline daily food intake was measured and then recorded daily for 6 days following sedation trials. Median (interquartile range [IQR]) time to onset of first effects for T10 and T30 was 2.9 minutes (2.5–5.3 minutes) and 2 minutes (1.4–2.9 minutes), respectively. Eighty-three percent of T10 and 100% of T30 hedgehogs lost righting reflex. The median (IQR) duration righting reflex was lost for T10 was 32.5 minutes (23.8–37.5 minutes) and it was lost for 47.5 minutes (36.25–63.75 minutes) for T30. Jaw tone was reduced in the majority of animals for both dosages but never lost. Heart and respiratory rate for both treatments remained within normal limits. Hedgehogs became rapidly hypothermic after induction. Flumazenil administration did not have a statistically significant effect on recovery time, but mean recovery times were 18 minutes faster for T10 hedgehogs administered flumazenil. There were no statistically significant differences in food intake within or between dosages of tiletamine-zolazepam at any time point for hedgehogs administered saline or flumazenil; however, mean food intake over the 6 days following T10 administration was 16 g/kg more for hedgehogs administered flumazenil. SC tiletamine-zolazepam at 10 and 30 mg/kg produces dose-dependent heavy sedation to light anesthesia in hedgehogs. Subjectively, while both dosages provided a sufficient depth of immobilization to permit a physical examination and noninvasive procedures like blood collection or diagnostic imaging, some jaw tone was maintained precluding endotracheal intubation. T30 provided a deeper level of immobilization than T10 but longer recovery times. Flumazenil administration did not have a statistically significant effect on recovery but recovery times were noticeably faster following SC flumazenil in hedgehogs sedated with T10. For hedgehogs immobilized with T10, mean food intake was greater when flumazenil was administered. Tiletamine-zolazepam provides an injectable option for immobilization of hedgehogs. [ABSTRACT FROM AUTHOR]

Blue poison dart frogs (Dendrobates tinctorius azureus) are commonly found in zoological institutions and are becoming popular in the pet trade. Sedation or light anesthesia is required for safe and effective handling of this species. In this study, the effect of subcutaneous administration of alfaxalone at two different doses (20 and 30 mg/kg) was evaluated in juvenile blue poison dart frogs (N = 10) in a prospective, randomized, blinded, crossover study. Heart rate, pulmonic respiratory rate, various reflexes, and behavioral parameters were monitored after drug administration. Both protocols resulted in rapid induction of sedation (median [range]) with loss of righting reflex: 20 mg/kg, 10 (10–20 min) and 30 mg/ kg, 10 (10–10 min). The time (mean ± SD) to return to spontaneous movement (20 mg/kg, 39.6 ± 7.6 min and 30 mg/kg, 54.5 ± 9.9 min; P < 0.01) and full recovery (20 mg/kg, 42.6 ± 8 min and 30 mg/kg, 61.6 ± 9.1 min; P < 0.01) after alfaxalone administration were significantly longer in the 30-mg/kg group. The frogs in both groups continued to remain responsive to tactile stimulation and retained palpebral reflexes. Alfaxalone induced cardiopulmonary depression and periods of apnea at both doses. The subcutaneous administration of 20 and 30 mg/kg alfaxalone resulted in clinically effective sedation in blue poison dart frogs. Sedation levels achieved in this prospective study would be adequate for a variety of noninvasive clinical procedures. [ABSTRACT FROM AUTHOR]

To evaluate if intramuscular (IM) lidocaine potentiates the sedative effects of alfaxalone and results in cardiopulmonary changes in sedated bearded dragons. Prospective experimental crossover study. A group of eight adult bearded dragons (Pogona vitticeps) weighing 334 ± 46 g. Animals were administered alfaxalone (10 mg kg−1 subcutaneously) and 15 minutes later either lidocaine 2% (4 mg kg−1) or 0.9% sodium chloride (0.2 mL kg−1) was administered IM in the thoracic limb. The treatments were randomized and separated by 7 days. Sedation was scored based on body position, eye closure, jaw tone, swallowing, pick up response, righting reflex and pelvic limb withdrawal reflex. Heart rate (HR) and respiratory rate (f R) were recorded every 5 minutes until recovery from sedation. Lidocaine had no significant effect on duration or depth of alfaxalone sedation. HR increased significantly for <10 minutes following lidocaine administration by a median (interquartile range) of 33% (28–37%; p = 0.024). No clinically significant effects on f R occurred following lidocaine injection. Administration of lidocaine 2% (4 mg kg−1) IM did not potentiate alfaxalone sedation but resulted in a transient clinically relevant increase in HR. [ABSTRACT FROM AUTHOR]

Positive contrast gastrointestinal (GI) studies are performed frequently in avian medicine to identify GI obstruction, luminal distension, and intracoelomic mass effects. However, repeated manual restraint and radiographic positioning may result in a stress-response and associated morbidity in birds, which can be attenuated by administration of sedative drugs. In mammals, many sedative drugs have been shown to affect GI transit times and motility. In this randomized, blinded, controlled prospective study, the effects of midazolam (M,6 mg/kg IM) and midazolam-butorphanol (MB,3 mg/kg each IM) on GI transit times were evaluated in 12 healthy cockatiels (Nymphicus hollandicus). Iohexol (20 mL/kg) was administered by crop gavage 15 minutes after induction of sedation, and fluoroscopic images were obtained at different time points. Both sedation protocols significantly affected GI transit times and motility, and the MB protocol had more pronounced effects. Overall median (range) GI transit times were 60 (30-120), 90 (30-120), and 120 (120-180) minutes for the control, M, and MB groups, respectively. Ventricular contractions were markedly reduced with both sedation protocols, while esophageal boluses were reduced only in the MB group. Visualization of the GI tract after iohexol administration was graded highest in the control group and poorest in the MB group. Our results show that commonly used sedative drugs have significant effects on GI transit time and motility in birds. Therefore, GI transit times obtained in sedated birds should not be compared to available reference transit times obtained from unsedated animals. [ABSTRACT FROM AUTHOR]

Alpha2-agonist anesthetic combinations are often used in rodent anesthesia but no information about their effects on cardiac function in chinchillas exists. The purpose of this study was to utilize echocardiography to evaluate the cardiovascular effects of dexmedetomidine–ketamine anesthesia in chinchillas. Echocardiographic examinations were performed in eight adult chinchillas under manual restraint and following dexmedetomidine (0.015 mg/kg) and ketamine (4 mg/kg) administration. Dexmedetomidine–ketamine anesthesia resulted in a significantly decreased heart rate, fractional shortening, cardiac output, and flow velocity across the aortic and pulmonic valves, and significantly increased left ventricular internal diameter in systole. The observed changes in echocardiographic parameters are similar to those previously reported in chinchillas anesthetized with isoflurane. [ABSTRACT FROM AUTHOR]

Abstract: Sedation of pet birds has become an increasingly popular technique to facilitate common clinical procedures, such as physical examination, blood collection, or radiography. Sedation provides immobilization, reduces vocalization, and attenuates the stress response caused by manual restraint. Midazolam and midazolam-butorphanol are the most commonly used drugs for sedation of pet birds, and they provide dose-dependent sedation with no significant side effects if used at the published dosages. The intranasal route of administration is a noninvasive alternative to intramuscular administration and has been shown to be a safe and effective technique to rapidly induce sedation in pet birds. Reversal with flumazenil should be performed in most cases of midazolam or midazolam-butorphanol induced sedation, in order to achieve rapid and complete recovery. [Copyright &y& Elsevier]

Administration of intranasal midazolam (2 mg/kg) was evaluated for sedation and effects on cloacal temperature, respiratory rate, and heart rate in manually restrained Hispaniolan Amazon parrots (Amazona ventralis). Adult parrots (n = 9) were administered either midazolam (2 mg/kg) or an equal volume of saline solution intranasally before a 15-minute manual restraint in a complete crossover study. Respiratory rate and sedation scores were recorded before and during capture and during and after 15 minutes of manual restraint. Heart rate and cloacal temperature were recorded during manual restraint. After restraint, the parrots received intranasal flumazenil (0.05 mg/kg) or an equal volume of saline solution, and the recovery time was recorded. In those birds that received midazolam, sedation was observed within 3 minutes of administration, and vocalization, flight, and defense responses were significantly reduced during capture. During manual restraint, the mean rate of cloacal temperature increase was significantly slower and remained significantly lower in birds that received midazolam compared with controls. Mean respiratory rates were significantly lower for up to 12 minutes in parrots that received midazolam compared with those receiving saline solution. Flumazenil antagonized the effects of midazolam within 10 minutes. No overt clinical adverse effects to intranasal midazolam and flumazenil administration were observed. Further studies on the safety of intranasal midazolam and flumazenil in this species are warranted. [ABSTRACT FROM AUTHOR]

Abstract: The clinical use of anesthetic agents in reptiles presents a number of unique challenges because of the diversity of the class Reptilia with respect to natural history, size, anatomy, and physiology. Reptiles are commonly maintained as companion animals, widely displayed in zoological institutions, and many species serve as subjects in laboratory facilities. Therefore, to become a skillful clinician, developing an understanding of anesthetic efficacy across reptile species is important. The objective of this review is to provide a current perspective on the practical application of anesthetic agents in commonly maintained pet reptile species. [Copyright &y& Elsevier]