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Frogs are popular exotic pets and research subjects. Manual restraint is routinely used for basic procedures in frogs, including examination and sample collection, but there is little information on its physiologic effects in amphibians. Previous literature suggested that amphibians lack emotional responses and, therefore, consciousness, based upon an inability to elicit stress tachycardia with gentle handling. To determine if manual restraint results in a stress tachycardia in frogs, 10 poison dart frogs (Dendrobates tinctorius) and 8 leopard frogs (Lithobates pipiens) were manually restrained and heart rate (HR) recorded at both the pectoral girdle and pelvic patch using a Doppler flow probe. Frogs were randomly placed in one of two (opaque versus translucent) types of plastic containers for 22 min and HR measured every 2 min through the bottom of the container using the frogs' pelvic patch area. Frogs were then removed from the container, manually restrained again, and HR recorded. Heart rate decreased significantly after the frogs were placed in the containers following manual restraint, and increased significantly for the second restraint period. There were no significant differences in measured HR between anatomic sites (pelvic vs. pectoral) or container types. Contrary to previous descriptions, these results demonstrated that, similar to other mammal and reptile species, frogs demonstrated stress tachycardia during manual restraint, and, therefore, clinicians and researchers should be mindful of induced stress when restraining amphibians. [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]

Historically, wetland toxin exposure studies have relied on single time point samples from stationary sampling devices. Development of passive sampling devices (PSDs) that can be attached to individual animals within wetland habitats has greatly improved in recent years, presenting an innovative sampling technology that can potentially yield individual-specific, quantifiable data about chemical exposure. In this study, silicone based PSDs were attached to the ventral skin of 20 northern leopard frogs ( Lithobates pipiens) with polypropylene sutures after radiotransmitters had been surgically implanted into the coleomic cavity. After a short recovery period, frogs were released back into the wetland habitat where they were acquired. The animals were located daily using radiotelemetry to assess how long PSDs would remain attached in the frogs' natural habitat. After one week, PSDs remained on 18 of the original 20 frogs. At two weeks, 17 frogs were recovered and no PSDs remained attached. Although valuable data can be obtained over a short time period, more research will be necessary to demonstrate the effectiveness of externally attaching silicone PSDs to northern leopard frogs for time periods longer than 1-2 weeks. [ABSTRACT FROM AUTHOR]