EUTHANASIA IN ZEBRAFISH: AN ISSUE TO BE DISCUSSED

• DOI: https://doi.org/10.22533/at.ed.973532517022

• Palavras-chave: Danio rerio; zebrafish; pain; euthanasia

• Keywords: Danio rerio; zebrafish; pain; euthanasia

• Abstract:

  Danio rerio, known as zebrafish, has become a widely used model in scientific research, with more than 5 million units used annually in 2017. Their popularity is due to their ease of handling, low cost and rapid reproduction, as well as the transparency of the embryos, which allows internal organs to be observed. However, the use of these fish raises ethical questions, especially in relation to animal welfare and pain during euthanasia and anesthesia procedures. The literature points to a growing concern about pain in zebrafish, since practices such as euthanasia, with methods approved by Directive 2010/63/EU, are still debated. MS-222 is widely used, but raises doubts about its efficacy and possible side effects. Alternative methods, such as rapid cooling and new anesthetics, are also discussed, revealing the need for more research into pain perception and the ethical management of zebrafish. The lack of consensus on the definition of pain in fish and the application of more humane practices are still crucial issues to be addressed in the scientific community.