Animal Welfare Act (AWA)

The Animal Welfare Act (AWA) is the principal US federal law regulating the humane treatment of certain animals used in research, teaching, testing, exhibition, transport, and the wholesale trade of pets. Enacted in 1966 as the Laboratory Animal Welfare Act (Pub. L. 89–544, signed August 24, 1966) and codified as amended at 7 U.S.C. §§2131–2159, the AWA is enforced by the US Department of Agriculture’s Animal and Plant Health Inspection Service (USDA APHIS), Animal Care unit, through the Animal Welfare Regulations at 9 CFR Chapter I, Subchapter A (Parts 1–3).

Scope and notable exclusions — what counts as an “animal”

Under 7 U.S.C. §2132(g), “animal” means any live or dead dog, cat, non-human primate, guinea pig, hamster, rabbit, or other warm-blooded animal used or intended for use in research, teaching, testing, experimentation, or exhibition, or as a pet. The definition carries statutory exclusions that are frequently misunderstood in a research-compliance context:

• Rats of the genus Rattus and mice of the genus Mus bred for use in research are excluded — USDA had administratively excluded them since the 1970s, and the 2002 Farm Bill (Pub. L. 107–171, §10301) codified the exclusion directly into the statutory definition.
• Birds bred for use in research are likewise statutorily excluded (also via the 2002 amendment).
• Cold-blooded (ectothermic) animals — fish, amphibians, reptiles — fall outside the definition entirely, since the statute is limited to warm-blooded animals.
• Farm animals (livestock and poultry) used or intended for use as food or fiber, or for improving animal nutrition, breeding, management, or production efficiency, are excluded when used for those agricultural purposes.
• Horses not used for research purposes are excluded.

Invertebrates (e.g., Drosophila, C. elegans) were never within scope, since the statutory definition never extended below warm-blooded vertebrates. In practice, this means the single largest population of animals actually used in US biomedical research — purpose-bred laboratory mice and rats — is not covered by the AWA at all, even though it is popularly assumed to be the law that governs “lab animals” in general.

Who is regulated, and how enforcement works

The AWA regulates four categories of entities that must register or obtain a license with APHIS: research facilities, dealers, exhibitors, and carriers/intermediate handlers. Registered research facilities are subject to recordkeeping requirements under 9 CFR Part 2 and to inspections by APHIS Animal Care — typically unannounced — to verify compliance with the housing, veterinary care, and handling standards set out in 9 CFR Part 3. Facilities must also submit an annual report (USDA Form 7023) itemizing animal use by pain/distress category. APHIS maintains a public inspection-report search tool for registered facilities.

How the AWA relates to IACUC oversight

The AWA is one of two principal legal bases requiring a US research institution to convene an Institutional Animal Care and Use Committee (IACUC) before animal work may begin — the other is the PHS Policy on Humane Care and Use of Laboratory Animals, which derives its own statutory authority from the Health Research Extension Act of 1985 (Pub. L. 99–158, 42 U.S.C. §289d) and is administered by NIH’s Office of Laboratory Animal Welfare (OLAW). The 1985 AWA amendments were the source of the IACUC requirement itself, and its current mechanics are set out at 9 CFR 2.31: a research facility’s CEO must appoint an IACUC of at least three members, including one veterinarian with laboratory-animal training and one member unaffiliated with the institution; the committee reviews and approves animal-use protocols before work starts, and conducts a program review and facility inspection at least once every six months.

The two legal bases do not cover exactly the same animals. The AWA’s IACUC requirement applies only to AWA-covered species — so, taken alone, it would not require IACUC review of purpose-bred mice, rats, or birds. PHS Policy closes that gap for federally funded work: it applies to any live vertebrate animal used in PHS-supported research, including the species the AWA excludes. An institution that receives PHS funding (e.g., from NIH) and also does AWA-covered animal work must satisfy both frameworks simultaneously, and most research institutions — particularly those seeking AAALAC International accreditation — adopt the Guide for the Care and Use of Laboratory Animals (National Research Council, 8th edition) as institutional policy and route all vertebrate-animal work through IACUC review, regardless of whether the AWA or PHS Policy alone would technically require it for a given species.

Legislative history

The AWA has been amended eight times since 1966: 1970 (extended coverage to all warm-blooded animals used in research, testing, exhibition, or the pet trade, and added handling/care/transport standards), 1976 (added animal-fighting provisions), 1985 (Improved Standards for Laboratory Animals Act — added the IACUC requirement, an exercise requirement for dogs, and a psychological well-being requirement for non-human primates), 1990, 2002 (Farm Bill, Pub. L. 107–171 — codified the rat/mouse/bird research-breeding exclusion), 2007, 2008 (Farm Bill — strengthened animal-fighting penalties), and 2013.

Distinguishing the AWA from related frameworks

The AWA sets minimum husbandry and facility standards and creates the licensing/registration/inspection regime described above; it does not itself require IACUC protocol-level scientific review of a study’s experimental design — that requirement comes from the 1985 amendment’s IACUC provisions and, for federally funded work, from PHS Policy. It is also distinct from the IRB/human-subjects framework (the Common Rule, 45 CFR 46), which governs human research participants and has no jurisdiction over animal welfare.

References

• Animal Welfare Act, 7 U.S.C. §§2131–2159 (as amended)
• Animal Welfare Regulations, 9 CFR Chapter I, Subchapter A, Parts 1–3
• USDA APHIS, National Agricultural Library — Animal Welfare Act overview
• PHS Policy on Humane Care and Use of Laboratory Animals (NIH OLAW)
• Health Research Extension Act of 1985, Pub. L. 99–158, 42 U.S.C. §289d
• Guide for the Care and Use of Laboratory Animals, National Research Council, 8th edition

Frequently Asked Questions

Are laboratory mice and rats covered by the Animal Welfare Act?

No. Rats of the genus Rattus and mice of the genus Mus that are bred for use in research are excluded from the AWA’s statutory definition of “animal,” an exclusion codified by the 2002 Farm Bill. Birds bred for research are excluded the same way. This means the animals most commonly used in US biomedical research fall outside the AWA’s direct regulatory reach, even though the law is often assumed to cover all laboratory animals.

Who enforces the Animal Welfare Act?

The USDA’s Animal and Plant Health Inspection Service (APHIS), through its Animal Care unit, enforces the AWA under the Animal Welfare Regulations at 9 CFR Chapter I, Subchapter A. APHIS registers or licenses research facilities, dealers, exhibitors, and carriers, and conducts periodic, typically unannounced, inspections to verify compliance.

What does the Animal Welfare Act require of research facilities?

Research facilities covered by the AWA must register with APHIS, keep records under 9 CFR Part 2, meet the housing, veterinary-care, and handling standards set out in 9 CFR Part 3, and file an annual report (USDA Form 7023) itemizing animal use by pain/distress category. APHIS Animal Care also carries out periodic inspections to verify compliance.

Does the Animal Welfare Act require IACUC review?

Yes, but only for AWA-covered species. The AWA’s 1985 amendments established the requirement for a research facility to convene an Institutional Animal Care and Use Committee (IACUC) to review and approve animal-use protocols before work begins. Because the AWA’s definition of “animal” excludes purpose-bred mice, rats, and birds, its IACUC requirement alone would not extend to those species; PHS Policy closes that gap for federally funded work.

When was the Animal Welfare Act passed?

The AWA was enacted in 1966 as the Laboratory Animal Welfare Act (Pub. L. 89–544, signed August 24, 1966) and has since been amended eight times, most substantially in 1985, when the IACUC requirement was added.

How does the Animal Welfare Act differ from PHS Policy?

The AWA and PHS Policy are separate legal frameworks that can both require IACUC review, but they cover different animals: the AWA applies only to AWA-covered species, excluding purpose-bred mice, rats, and birds, while PHS Policy applies to any live vertebrate animal used in PHS-supported research. An institution that does AWA-covered animal work and also receives PHS funding must satisfy both frameworks simultaneously.