Assessing the safety and suitability of nesting material for singly housed mice with surgically fitted head plates.

Nesting material, for example shredded paper, is a common form of enrichment for laboratory mice. However, there has been limited research performed regarding its apparent safety when given to mice fitted with exteriorised devices such as head plates. Anecdotally, shredded paper has been deemed unsafe for use with such animals due to frequently observed entanglement. This study assessed the safety of four nesting materials (Pure Comfort White, Rodent Roll, Short Paper Shavings and Facial Tissue) to identify a suitable alternative to shredded paper. The four nesting materials were each tested on 5 head plate mice over a 14-day period. The quality of the nests produced was scored throughout the trial period and incidences of tangling monitored. Tangling was only observed in the Facial Tissue group, and the highest quality nest scores were recorded in the Pure Comfort White group. As shredded paper has been anecdotally alleged to cause entanglement, Pure Comfort White, Rodent Roll and Short Paper Shavings may present more suitable options, given that their use did not result in any incidences of tangling throughout this trial. Pure Comfort White was concluded to be the safest and most suitable nesting material for head plate mice as it produced nests of high quality while reducing the risk of entanglement.