Which of the following is NOT a requirement under the Animal Welfare Act for research facilities?

The requirement regarding the provision of unlimited space for all animals is not stipulated in the Animal Welfare Act for research facilities. The Act mandates that research facilities must provide adequate housing to ensure the well-being of animals, but it does not require unlimited space. Adequate housing involves considerations for the species, size, and social needs of the animals, allowing for their comfort and health within reasonable constraints.

In contrast, the other options listed—providing veterinary care, enrichment activities, and proper nutrition—are established requirements in the Animal Welfare Act. Research facilities must ensure that animals receive necessary veterinary care to maintain their health, provide enrichment activities to promote their psychological well-being, and supply proper nutrition to meet the dietary needs of the animals according to medical and species-specific guidelines. These requirements collectively aim to ensure humane and ethical treatment of animals used in research, reflecting the Act's broader goals of animal welfare.