Animal Enrichment Program

Last Review Date: October 9, 2018


The University of Montana Department of Laboratory Animal Resources (LAR) is committed to providing an enrichment program for all animals used in research, teaching, and testing.  All species housed in LAR receive social enrichment through paired or group housing unless single housing is scientifically or medically justified.  Additional species-specific enrichment (e.g., toys, nesting material, novel foods) is provided with pre-approval by the Principal Investigator.

Autoclaved enrichment is placed at the time of bedding changes for all rodents, ensuring placement at least once weekly for those housed in static micro-isolators and every other week for those housed in ventilated cages.  One or more of the items listed below may be present at any given time.  Larger animals such as rabbits may have enrichment rotated on a biweekly basis. 

  • Mice:  social housing and autoclaved Enviro-DriTM, toilet paper rolls, manufactured  
            huts, hammocks, and NestletsTM for breeders.  All single housed mice and rats
            require two forms of enrichment - twists, sunflower seeds, hammocks.
  • Wild-derived mice:  Shepherd Shacks®, Enviro-DriTM, NestletsTM.  All rodents are
            given 3-5 irradiated sunflower seeds from Envigo at each bedding or cage
            change.
  • Sentinel mice: Enviro-Dri, toilet paper rolls, NestletsTM or Shepherd Shacks® if singly
            housed.  All rodents are given 3-5 irradiated sunflower seeds from Envigo at
            each bedding or cage change.
  • Rats:  KimWipesTM, human socialization, nylabones, wood blocks, large tubes, and   
            fruit loops.  All rodents are given 3-5 irradiated sunflower seeds from Envigo at
            each bedding or cage change.
  • Birdssand boxes, mirrors, rattles, beak sharpeners, food supplements (e.g., egg,
            meal worm), perching devices, naturalistic environment (outdoor aviaries)
  • Hamsters:  sunflower seeds, wood chew blocks, toilet paper rolls, egg cartons,
            mouse Igloo, Mouse Igloo Fast-Trac, Shepherd shacks®
  • Guinea pigs:  hay, human socialization, clear plastic shelters, nylabones, chew
            blocks, rubber balls
  • Rabbits:  rubber balls, empty soda cans, Timothy hay, human socialization
  • Degus: timothy hay, wooden blocks, nylabones, flower petals, apple wood chews,
            PVC tubes, and shepherd shacks.  Post-op degu also receive seeds.
  • Peromyscus: Toilet paper rolls, Enviro-Dri, Nestlets (breeders), seeds
  • Snowshoe hares: Squeeze'N Toss Footballs, Taz Ball, Havaball, Nobbly Wobbly


Below is a list of approved non-food item enrichment for USDA rodent, lagomorph, and Lepus species:

  1. Running wheels (plastic or metal as appropriate for the size of the animal.
  2. Chew toys
    1. "Nylabone" -type
    2. Wooden blocks
    3. Apple branches - organically grown only (degus and snowshoe hares)
    4. Pine branches (snowshoe hares)
  3. Hanging platforms (comprised of durable plastic and suspended by shower curtain clips.
  4. Polycarbonate huts - mouse igloo
  5. Durable rubber balls or shapes
    1. Squeez'n toss footballs, Taz Ball, Havaball, Nobbly Wobbly
  6. Polycarbonate balls
  7. Timothy or sisal products made for rabbits or hares (mats, huts, etc.)
  8. Durable, empty plastic bottles or aluminum cans for noisemakers
  9. Polycarbonate run-about balls for rodents (requires documented, supervised acclimation)
  10. Durable plastic shelters for climbing and hiding (rabbits and hares)
  11. Paper products, sisal-type, or other natural nesting materials
    1. Toilet paper rolls
    2. Environ-Dri, Nestlets
    3. Shepherd Shacks
    4. Egg cartons
    5. KimWipes
    6. Paper twists
  12. PVC tubes