Best Practices in Xenopus Housing, Husbandry, and the 3Rs.

Appropriate housing and husbandry practices for laboratory Xenopus are key to maintaining good welfare standards and generating reliable experimental results. Although we lack empirical evidence for many housing and husbandry practices, Xenopus have been used as a laboratory species for decades. As a result, best practices have evolved over time as researchers and staff at frog facilities have built up experience on what helps to keep frogs in the best condition. Different Xenopus species have different care needs; this chapter covers housing and husbandry protocols for Xenopus laevis and Xenopus tropicalis. These are the current protocols of the European Xenopus Resource Centre (EXRC) in Portsmouth, United Kingdom. The EXRC provides services supporting researchers using Xenopus in research, including guidance on housing, husbandry, breeding and colony management, and maintaining healthy frogs to enable collection of reliable data. Here, we describe how to setup and seed a new recirculating system, surface sterilization of embryos, and identification of individual frogs. We also outline best practices for each life stage, including indicators of good health and normal behavior and signs of distress or poor health and protocols for handling disease outbreaks.