Lecture 30- Contemporary Issues in Laboratory Animal Medicine

What are the 3Rs in laboratory animal research?

Reduction, Replacement, Refinement.

Define Reduction and give an example.

Using the smallest number of animals necessary; using statistical models to determine sample size.

Define Replacement and give an example.

Using nonanimal methods or lower‑consciousness species; examples: cell culture, organ‑on‑a‑chip, AI/computer models, using mice instead of NHPs.

Define Refinement and give an example.

Minimizing pain/distress; examples: analgesia, humane endpoints.

What is the Animal Welfare Act (AWA)?

Federal law (1966) regulating treatment of animals in research, teaching, exhibition, and transport.

Which agency enforces the AWA?

USDA.

What animals are NOT covered by the AWA?

Cold‑blooded animals, birds, rats, mice, and food/farm animals.

What does the AWA require?

Regular inspections of animal facilities.

What is the Guide for the Care and Use of Laboratory Animals?

Essential document outlining standards for care, housing, transport, and IACUC requirements.

Which institutions must follow The Guide?

All NIH‑funded and AAALAC‑accredited institutions.

What animals are NOT covered by The Guide?

Agricultural animals, wildlife, certain aquatic species.

What is AAALAC?

Voluntary accreditation ensuring high ethical standards in animal research.

What is the IACUC?

Institutional Animal Care and Use Committee overseeing all animal research at an institution.

What does the IACUC report to?

OLAW.

What does the IACUC do?

Approves and monitors protocols, conducts semiannual inspections, oversees compliance.

What is required before research can begin?

An approved IACUC protocol.

Minimum number of IACUC members?

Five.

Required IACUC member roles?

Veterinarian, scientist, nonscientist, community member.

What percentage of research animals are mice and rats?

Approximately 95%.

What percentage of research animals are NHPs, dogs, pigs, cats, ferrets, etc.?

Less than 1%.

What species is Mus musculus?

The laboratory mouse.

How many mouse strains exist?

Over 8,000.

Most common mouse strain?

C57BL/6.

What is an IVC system?

Individually ventilated cages connected to rack ventilation, allowing individualized environments.

How often are mouse cages changed?

Every 7-14 days.

Why must nesting material be transferred during cage change?

Mice are highly scent‑dependent.

Why is group housing ideal for mice?

Supports natural behavior and welfare.

Why can male mice be problematic in groups?

High aggression.

What risk occurs with multiple litters in a cage?

Overcrowding.

What species is Rattus norvegicus?

The laboratory rat.

Common rat strains?

Sprague‑Dawley, Wistar, Long‑Evans.

How do male rats differ from male mice socially?

Male rats fight less.

Which NHP species are commonly used in research?

Rhesus macaques, cynomolgus macaques, marmosets, African green monkeys.

What percentage of research uses NHPs?

Less than 1%.

What are key NHP housing requirements?

Social housing, large cage sizes, environmental enrichment; single housing requires justification and IACUC approval.

Why are outdoor field enclosures used?

Allow natural social structures and environments.

What is a squeeze cage used for?

Safe restraint and training for procedures; reduces chemical/physical restraint use.

Why do NHP facilities have behavioral management units?

Healthy, enriched animals produce better science; units manage enrichment, training, and group housing.

Describe rhesus macaque social structure.

Matrilineal; females inherit rank and stay in natal group; males disperse and enter new groups at low rank.

How is dominance enforced?

Aggression.

What are consequences of low rank?

Less access to food, mates, space; higher disease and injury rates.

What is an overthrow?

One matriline overtaking another; can be aggressive and deadly.

Why were chimpanzees historically used in research?

Genetic similarity to humans; used for vaccines, hepatitis, neuroscience.

When were chimpanzees listed as endangered?

1990; extended to captive chimps in 2015.

When did NIH retire research chimpanzees?

2013.

When did invasive chimpanzee research stop?

2015.

Where do most research chimpanzees live now?

Sanctuaries or retirement facilities.

Which species followed a similar phase‑out?

Mangabeys (SIV research).

What are current issues in lab animal medicine?

Animal rights activism, increased public scrutiny, legislative attempts to restrict dog/NHP research, controversies at primate centers, rise of alternative research methods.

What is the role of a laboratory animal veterinarian?

Ensure animal health and welfare, regulatory compliance, perform procedures, collaborate with researchers, support husbandry and behavior programs.

What are examples of alternatives to animal research?

Cell culture, organ‑on‑a‑chip, AI/computer modeling, lower‑consciousness species substitution.

What was the first major law regulating animal research?

Cruelty to Animals Act (UK, 1876); required licensing and inspection