Humane Anesthesia and Pain Management in Amphibian Limb Surgery of Rana pipiens

Abstract

Adult Rana pipiens frogs are used as a model to investigate mechanisms of vertebrate organ regeneration, anti-tumor ribonucleases, zoological impacts of various pollutants, oncogenesis, neuroplasticity, and neurogenesis. In regenerative biology, the adult Rana pipiens frog is an important alternative to other frog models, such as Xenopus laevis, because it offers the opportunity to study and attempt to augment limb regeneration in an animal that spends significant time out of water and bears weight on its limbs. To elucidate regenerative processes, it is necessary to amputate the limb to study the processes associated with wound healing, blastema formation, and morphogenesis. Being able to revive the animal successfully with little or no side effects is paramount to these studies. Anesthesia and the effect it has on the frogs can vary based on the methods and post-operative care exercised during surgery. However, useful information is not readily available regarding current anesthesia methods or effective and humane analgesia use in amphibians. Amphibian patients are very sensitive to drug dosages, changes in temperature, humidity and water quality; here, special attention is given to these factors. This protocol establishes a humane anesthesia technique while maintaining physiological homeostasis during procedures in amphibians as well as a post-operative care plan addressing the clinical benefits of using analgesics in pain management. Suggestions for infection prevention are covered with a sample treatment plan to ensure that all of the animals have a positive outcome and all of the surgeries have reproducible results.

A Protocol for Prolonged Surgical Anaesthesia with Recovery in Fire Salamanders Using Tricaine Mesylate (MS-222): A Case Series

“…22 Buprenorphine, a partial mu agonist has been recorded providing significant analgesia. 34 Typically, higher doses have been used; 14 mg/kg in leopard frogs 1 as opposed to 0.5 mg/kg used here. Notably, a multimodal approach to analgesia was used for surgery in this case series and reduced doses were deemed appropriate.…”

Anesthetic MS-222 eliminates nerve and muscle activity in frogs used for physiology teaching laboratories

“…Physiologically responsive frogs typically exhibit a corneal reflex when the eye is touched, and this behavior is dependent on reflexive circuits through the cranial nerves (17,20,23). A firm pinch of the toe to elicit a withdrawal reflex is a common test of nociceptive responses in amphibians (6,16,18,20,31,32). Animals were judged to be appropriately unaware of pain if they were unresponsive to both of these tests.…”

A Comparison Of The Analgesic Effects Of Fentanyl And Butorphanol In African Clawed Frogs (Xenopus laevis) Under Tricaine Methanesulfonate (MS222) Anaesthesia

“…With few exceptions and when given via immersion, MS222 is described as being a safe anaesthetic with a low impact on heart rate and oxygen saturation [13-15 & 19]. In pain research, amphibians have gradually established a small but adequate status as animal models, even though their ability for nociception and to pain perception, has been controversially discussed in the past [20][21][22]. In 1969, Kaplan declared that pain perception is not particularly developed in all poikilotherms due to their low phylogenetic position and underdeveloped brain [23].…”