# Vocalisations as a potential indicator of parturition in C57BL/6J mice

## TL;DR

This study explores how mouse vocalizations during birth can help improve breeding management in lab settings.

## Contribution

The study shows that vocalizations during parturition can be used for automated detection in mice.

## Key findings

- Vocalizations were detected during parturition in both single and pair-housed mice.
- Vocalizations decreased after parturition and were minimal before it, except for ultrasonic sounds in pair-housed mice.
- The study supports using vocalizations as a basis for automated parturition detection in HCM systems.

## Abstract

Breeding management in laboratory rodents is challenging, particularly around parturition and the neonatal period, where cage disturbance is often avoided in an attempt to limit neonatal mortality. Nevertheless, cage-side observations and single daily checks frequently underestimate pup numbers born and miss parturition complications. Home Cage Monitoring (HCM) systems are gaining popularity in animal facilities, detecting critical events such as food availability and activity levels. Parturition is a complex event involving specific patterns of behaviour, activity and vocalisations. In this study, audio and video data were collected from parturition events of single-housed C57BL/6J females and breeding pairs housed in a prototype rack with integrated microphones. Vocalisations were detected during parturition in both housing conditions, with minimal vocalisations observed prior to parturition, except for ultrasonic sounds in pair-housed mice (Mus musculus). After parturition, all vocalisations gradually decreased. Despite limitations such as the need for post-event analysis and the focus on a single mouse strain, this study suggests that detecting vocalisations can be a promising basis for developing automated parturition detection. This highlights the potential of HCM systems for improving breeding management and welfare in laboratory rodent colonies.