The Animal Welfare Act (AWA) of 1966, the foundational legislation governing the treatment of animals in research facilities, has recently undergone scrutiny as advocates call for updated standards and broader legal protections. Amendments to AWA guidelines regarding birds were introduced in 2023, but concerns remain regarding the scope of species covered and the level of oversight provided.
Currently, the AWA, enforced by the Animal and Plant Health Inspection Service (APHIS) of the USDA, excludes warm-blooded animals commonly used in research – specifically, domestic mice and rats bred for scientific purposes, as well as farm animals utilized in agricultural research. This exclusion has drawn criticism from animal welfare groups who argue that these animals, despite their prevalence in laboratories, deserve the same protections as other species.
Alongside the AWA, the Health Research Extension Act of 1985 established the Public Health Service (PHS) Policy on Humane Care and Apply of Laboratory Animals. This policy provides a legislative mandate for humane treatment, but its application is distinct from the AWA. Institutions receiving funding from the Public Health Service are required to adhere to the PHS Policy, which mandates that animal care and use programs be based on the standards outlined in the Guide for the Care and Use of Laboratory Animals, published by the National Academies Press.
The Guide, a product of a committee comprised of scientists, veterinarians, and non-scientists, details accepted standards for animal housing, research conduct, and facility design. The PHS Policy requires institutions to base their animal care and use programs on this Guide. Recent updates to the Guide, including those related to the 21st Century Cures Act, are prompting institutions to review and potentially revise their existing protocols.
Veterinary care provisions have been a component of the AWA since 1970, yet the specifics of veterinary oversight and the resources allocated to animal health within research facilities remain areas of ongoing discussion. The AWA also regulates zoos, exhibitors, and animal dealers, extending its reach beyond purely scientific research.
Clinical veterinary research conducted on client-owned animals, however, operates in a regulatory gray area. According to recent analysis, such research is not subject to ethical review under either European or UK legislation, as it falls outside the definition of ‘non-experimental veterinary practice.’ This distinction highlights a potential gap in oversight for animals receiving treatment within a clinical setting that also contributes to research data.
The National Institutes of Health’s Office of Laboratory Animal Welfare (OLAW) provides resources and guidance on implementing the standards outlined in the Guide, including information on navigating departures from those standards. OLAW has also released webinars and other resources to assist institutions in understanding and applying the latest updates.
As of February 26, 2026, the USDA has not announced any further planned revisions to the AWA, and the PHS Policy remains under periodic review. The next scheduled meeting of the Advisory Committee on Animal Welfare, which advises the USDA on AWA regulations, is currently unannounced.
