The hard-hitting tooth—Does a scheduled teeth check reduce the number of mice found dead with malocclusion? (2023)

Ciupa, J.

Abstract

Malocclusion is a common dental disorder for laboratory mice. Characterised with improper alignment of teeth, if the incisors of the mouse have become overgrown or are missing it can significantly impact animal welfare. Malocclusion is evident around the first 2-5 weeks of age for mice. Therefore, it is hypothesised that a regular welfare check, the POST WEAN CHECK (PWC) at 5 weeks would significantly increase the health concerns (HC) found as more mice would be diagnosed and caught before being found dead. A retrospective data analysis of the HCs from September 2020 to March 2021 were compared to September 2021 to March 2022. The implementation of the PWC was the end of March 2021. The results show that more cases of malocclusion were identified after the implementation of the PWC. There were 36 malocclusion cases before the PWC and 103 after the implementation. However, there was no significant decrease of found dead mice reported after the implementation of PWC. Nonetheless, these results suggest that more mice were diagnosed and thus given teeth clipping before severe suffering seen in maloccluded mice.