The Institutional Animal Care and Use Committee (IACUC) Aquatic Animals: Analgesia and Anesthesia formulary The appropriate use of pain medications (analgesics) and anesthetics is a critical aspect of the proper care and use of animals in research. Not only are they required by regulatory agencies when an animal experiences more than momentary pain or discomfort, but minimization of pain and stress typically results in better, more reproducible results. (Resources to Aid in Recognition of Pain and Distress; Pain Relief in Animals) The following is a listing of dosages for many of the more commonly employed analgesics and anesthetics, and is meant as a guide during protocol preparation. In all cases, animals may only be utilized with a currently approved IACUC protocol and any changes in the analgesics or anesthetics must be accompanied by an amendment to the protocol even if the medication is listed in this formulary. The formulary is not meant to be an all-inclusive listing. If you would like to use a drug not included in this listing, please contact a DLAM veterinarian to discuss its use in your protocol. Variability amongst models The doses listed in the formulary were collected from the comparative medicine literature, but these articles typically evaluate rodent drug doses using the most common strains or stocks and healthy animals in the case of large animal trials. Moreover, it is well recognized there can be considerable variation in the effect of drugs across individuals, strains and stocks, as well as between sexes. Thus, it is critical to evaluate all animals, including strains or models that you have created, to determine if the doses and/or drugs chosen are appropriate in your study. If your research focuses on a particular body system, it is also important to consider the effect of the drug on that system. We encourage you to work with the Division of Laboratory Animal Medicine (DLAM) veterinarians and/or review the literature for this information. There have been a considerable number of articles in the comparative medicine literature focusing on these considerations. Selecting an appropriate analgesic or anesthetic In most cases, the formulary includes information regarding the time of onset and duration of effect. In general, the opiates are shorter-acting than Non-Steroidal Anti-inflammatory Drugs (NSAIDs) and can be effectively used at the time of the procedure to dampen the induction of the pain pathways. The pain and discomfort which occurs later is typically attributed to inflammation, therefore, NSAIDs are used in many postoperative regimens. When using multiple drugs, it is also critical to consider their potential interactions. For example, certain opiates can actually antagonize each other s actions, thus cancelling their beneficial effect. Additional resources Currently there are a number of excellent textbooks about laboratory animal anesthesia and pain management available online through the UNC Library system. A select few are as follows:
1) http://search.lib.unc.edu/search?r=uncb6247400 Laboratory animal anesthesia, Flecknell, P. A. Elsevier/Academic Press, Amsterdam, Boston, 2009. 2) http://search.lib.unc.edu/search?r=uncb6554539 Handbook of laboratory animal science. Volume 1, Essential principles and practices, CRC Press, Boca Raton, FL, 2011. Note: is a non-pharmaceutical grade compound. Section 11.3 of the protocol form must be completed when using this compound. Fish Formulary Drug name Dose and Route Frequency Notes Anesthetics Analgesics 25-250 mg/l in water bath or on gills to effect bicarbonate or other buffer; good margin of safety, FDA approved, 21 day withdrawal period for food Butorphanol Tramadol Carprofen 0.1-0.4 mg/kg 5.0-10 mg/kg PO 2.0-4.0 mg/kg every 24 every 48-72 every 72-96 efficacy dose varies with species Flunixin Meglumine 0.25-0.5 mg/kg every 72-96 side effects (such as gastric ulceration) are possible with long-term use Ketoprofen 2.0 mg/kg every 24-48 Meloxicam 0.1-0.2 mg/kg every 24-48
Note: Some of these compounds are non-pharmaceutical grade compounds so fill out section 11.3 of the protocol form when using these compounds. Xenopus Formulary Drug name Dose and Route Frequency Notes Anesthetics 500-5000 mg/l in water bath to effect, (often 10-15 min) bicarbonate or other buffer; FDA approved 200-5000 mg/l in water bath to effect, (often 10-15 min) bicarbonate or other buffer Pure benzocaine is not water soluble and should be avoided for anesthesia or euthanasia because it requires the use of acetone or ethanol solvents, which may be irritating to tissues. AVMA Guidelines p77 Analgesics Xylazine 10 mg/kg every 12-24 Butorphanol 33 mg/kg Buprenorphine Ketorolac 14 mg/kg SC dorsal lymph sac 26 mg/kg SC Flunixin Meglumine 25 mg/kg Note: All these compounds are non-pharmaceutical grade compounds so fill out section 11.3 of the protocol form when using these compounds.
Aquatic Euthanasia Drug Dose and Route Species Notes >250-500 mg/l in water or on gills 5-10 g/l in water, or injected or in lymph sac 20% (or 182 mg/kg) gel, 2.0 cm, topically or > 250 mg/l immersion >250 mg/l in water for immersion 2-Phenoxyethanol 0.3-0.4 mg/l (>0.5-0.6 ml/l) Quinaldine sulfate Carbon dioxide depends on species and water temp, ph, and mineral content, > 100 mg/l by immersion saturate the gas into the water Xenopus, frogs Xenopus, frogs Fish bicarbonate or other buffer - >10 min immersion after opercular movement cessation ; not acceptable for animals intended for consumption without a 21 day withdrawal bicarbonate or other buffer, > 1 hr immersion may be required; a subsequent physical method is recommended Gel can take up to 5 for effect; buffer solution used for immersion to neutral ph with sodium bicarbonate or other buffer; a subsequent physical method is recommended bicarbonate or other buffer, not acceptable for animals intended for consumption more efficient immersion agents available; not acceptable for animals intended for consumption bicarbonate or other buffer; not acceptable for animals intended for consumption Category is Acceptable with conditions. source: only from cylinders of compressed gas; use only in well ventilated areas; while low regulatory priority, still is not approved for animals intended for consumption Pure benzocaine is not water soluble and should be avoided for anesthesia or euthanasia because it requires the use of acetone or ethanol solvents, which may be irritating to tissues. AVMA 2013 Guidelines p77 See pg 73 of the AVMA Guidelines for the Euthanasia of Animals for acceptable methods of euthanasia of in research settings, including some physical methods. Zebra embryos < 3 dpf require a 2-step method with a dilute hypochlorite solution. Older life stages (> 3 dpf up to larvae life stage) may require an adjunctive method with a dilute hypochlorite solution. AVMA Guidelines p71-3
References: Weber, E.S. (2011) Fish Analgesia: Pain, Stress, Fear Aversion or Nociception? Veterinary Clinics of North America: Exotic Animal 14: 21-32. Stevens, C.W. (2011) Analgesia in Amphibians: Preclinical Studies and Clinical Applications. Veterinary Clinics of North America: Exotic Animal 14: 33-44. AVMA Guidelines for the Euthanasia of Animals. 2013 edition.