title: Evaluating methods of mouse euthanasia on the oocyte quality: cervical dislocation versus isoflurane inhalation.
abstract: Cervical dislocation is a commonly used method of mouse euthanasia. Euthanasia by isoflurane inhalation is an alternative method which allows the sacrifice of several mice at the same time with an anaesthesia, in the aim to decrease pain and animal distress. The objective of our study was to assess the impact of these two methods of euthanasia on the quality of mouse oocytes. By administering gonadotropins, we induced a superovulation in CD1 female mice. Mice were randomly assigned to euthanasia with cervical dislocation and isoflurane inhalation. Oviducts were collected and excised to retrieve metaphase II oocytes. After microscopic examination, oocytes were classified into three groups: intact, fragmented/cleaved and atretic. Intact metaphase II oocytes were employed for biomedical research. A total of 1442 oocytes in the cervical dislocation group were compared with 1230 oocytes in the isoflurane group. In the cervical dislocation group, 93.1% of the oocytes were intact, versus 65.8% in the isoflurane group (P ≤ 0.001). In light of these results, we conclude that cervical dislocation is the best method of mouse euthanasia for obtaining intact oocytes for biomedical research.
authors.affiliation: Biogénotoxicologie - Santé Humaine et Environnement, Aix-Marseille Université, UMR CNRS 7263 IMBE, FR CNRS 3098 ECCOREV, Faculté de Médecine, 27 Bd Jean Moulin, 13005 Marseille, France. audrey.roustan@laposte.net
authors.forename: Audrey
authors.initials: A
authors.lastname: Roustan
authors.forename: Jeanne
authors.initials: J
authors.lastname: Perrin
authors.forename: Anaïs
authors.initials: A
authors.lastname: Berthelot-Ricou
authors.forename: Erica
authors.initials: E
authors.lastname: Lopez
authors.forename: Alain
authors.initials: A
authors.lastname: Botta
authors.forename: Blandine
authors.initials: B
authors.lastname: Courbiere
mesh_terms: D000280:Administration, Inhalation; D018685:Anesthetics, Inhalation / Q000633:toxicity*; D023401:Animal Use Alternatives; D000827:Animal Welfare; D000818:Animals; D016477:Artifacts; D002574:Cervical Vertebrae; D037901:Euthanasia, Animal / Q000379:methods*; D005260:Female; D007530:Isoflurane / Q000633:toxicity*; D051379:Mice; D008815:Mice, Inbred Strains; D009865:Oocytes / Q000187:drug effects* / Q000473:pathology; D006080:Ovarian Follicle / Q000187:drug effects / Q000473:pathology; D010053:Ovary / Q000187:drug effects / Q000473:pathology; D013119:Spinal Cord Injuries / Q000401:mortality / Q000662:veterinary*; D013480:Superovulation
chemical_list: D018685:Anesthetics, Inhalation; D007530:Isoflurane