Euthanasia of Rodent Fetuses and Neonates
The Report of the AVMA Panel on Euthanasia does not provide specific recommendations for the euthanasia of prenatal or neonatal animals. The following guidelines are suggested to assist individual Animal Care and Use Committees at the NIH in reviewing proposals which involve the use of rodent fetuses or neonates. Fetuses:
Neonates:
In all cases, the person performing the euthanasia must be fully trained in the appropriate procedures. References:Phifer CB, Terry LM. 1986. Use of hypothermia for general anesthesia in preweanling rodents. Physiol & Behav 38:887-890.
BU IACUCInstitutional Animal Care and Use Committee IACUC oversee... Approved October 2008, Revision 1: February 2012, Revised March 2019, Approved April 2019, Revised February 2021. Federal PolicyPHS Policy requires Institutional Animal Care and Use Committees (IACUCs) to determine that methods of euthanasia utilized in research proposals are consistent with the Report of the American Veterinary Medical Association Panel on Euthanasia (AVMA American Veterinary Medical Association Guidelines on Euthanasia) unless a deviation is justified for scientific reasons in writing by the investigator. IACUC approval of such deviations must be project-specific and include critical review of assertions of scientific necessity.
Suggested Common Methods for Euthanasia
Verifying DeathDeath must be verified after euthanasia and prior to disposal. A combination of cessation of heartbeat and respiration, loss of corneal and toe pinch reflexes, graying of mucous membranes, or rigor mortis alone may be used to verify death. Many of these signs may be difficult to evaluate in small rodent species, especially if they’ve been euthanized via CO2, so secondary, physical methods are recommended. An adjunctive method is recommended for CO2 euthanasia. Unintended recovery must be prevented by use of appropriate exposure times and concentrations of CO2 or by physical means outlined below.
Unintended recovery of animals after apparent death from CO2 (e.g. in necropsy coolers) is a documented occurrence. Such incidents constitute serious noncompliance with PHS policy and the Guide for the Care and Use of Laboratory Animals, so they must be reported to OLAW. Researchers must ensure the animal is dead before disposal, tissue collection, or leaving the animal unattended. 1. AVMA Panel on Euthanasia, AVMA Guidelines for Euthanasia of Animals, 2020 Edition https://www.avma.org/sites/default/files/2020-01/2020-Euthanasia-Final-1-17-20.pdfEuthanasia of Rodents BU IACUC 20192. Boivin, G. P., Bottomley, M. A., & Grobe, N. (2016). Responses of Male C57BL/6N Mice to Observing the Euthanasia of Other Mice. Journal of the American Association for Laboratory Animal Science : JAALAS, 55(4), 406–411.3. Boivin, G. P., Hickman, D. L., Creamer-Hente, M. A., Pritchett-Corning, K. R., & Bratcher, N. A. (2017). Review of CO₂ as a Euthanasia Agent for Laboratory Rats and Mice. Journal of the American Association for Laboratory Animal Science : JAALAS, 56(5), 491–499.4. Hickman D. L. (2018). Home Cage Compared with Induction Chamber for Euthanasia of Laboratory Rats. Journal of the American Association for Laboratory Animal Science : JAALAS, 57(6), 729–733. Advance online publication. https://doi.org/10.30802/AALAS-JAALAS-17-000160.5. Moffitt, A. D., Brignolo, L. L., Ardeshir, A., & Creamer-Hente, M. A. (2019). The Role of Emotional Contagion in the Distress Exhibited by Grouped Mice Exposed to CO₂. Journal of the American Association for Laboratory Animal Science : JAALAS, 58(4), 430–437. https://doi.org/10.30802/AALAS-JAALAS-18-000098 |