Final answer:
The USDA is responsible for the registration of animals used in research facilities and teaching institutions, as part of the enforcement of the Animal Welfare Act.
Step-by-step explanation:
The government agency responsible for the registration of animals used in research facilities and teaching institutions is the United States Department of Agriculture (USDA). This registration is part of the enforcement of the Animal Welfare Act (AWA), which advocates for humane practices in laboratories and includes requirements for researchers to register their use of certain animals. While the FDA oversees various aspects of public health, including veterinary products through its Center for Veterinary Medicine, it is the USDA that directly manages the registration connected to the use of animals in research and teaching environments.