What enrichment categories are recommended for laboratory rodents?

The AAALAC Guide (8th edition) recommends four main categories: nesting material (for thermoregulation and natural behavior), gnawing objects (for dental health), foraging opportunities (to promote exploratory behavior), and structural enrichment (shelters and tunnels for hiding and exercise). This planner covers all four.

Do breeding cages need extra enrichment?

Yes. Breeding cages should receive additional nesting material to support nest building, which is critical for pup survival and thermoregulation. This planner automatically adds extra nesting material for breeding cages.

What special enrichment do single-housed animals need?

Single-housed animals lack social enrichment, so AAALAC requires compensatory environmental enrichment. This typically includes additional structural items (shelters, tunnels) and may include extra foraging opportunities. The planner adds extra structural enrichment for single-housed cages.

How often should enrichment items be replaced?

Replacement frequency varies by item type. Nesting material and gnawing sticks are typically replaced at each cage change (weekly). Structural items like igloos are replaced when damaged (monthly to quarterly). Foraging items are replenished every few days. The planner shows replacement schedules for each item.

ToolsConductScience tool

Animal Welfare & 3RsFree in-browser calculator

Enrichment Item Planner.

Plan species-appropriate enrichment items across nesting, gnawing, foraging, and structural categories. Quantities, costs, and evidence-based citations for AAALAC compliance.

Run calculator Request a Quote

PrivateData stays in your browser

LiveNo sign-up required

Validated2026-04-08

CitableMethods and citation included

Calculator

Results update in place

Try it out

Load example enrichment item planner data to see the full workflow

Facility Setup

Total cages *

Species *

Budget/cage ($) *

Breeding cages

Single-housed cages

Enrichment Categories

NestingGnawingForagingStructural

Shopping List

Items

Total Cost

$8.20

Cost/Cage

$0.41

Budget

$91.80

remaining

Item	Category	Qty	Unit $	Total $	Replace	Note
Shredded paper strips	Nesting	20	$0.05	$1.00	7d	Low-cost nesting substrate; preferred by breeding females for nest building.
Wooden tongue depressor	Gnawing	40	$0.03	$1.20	7d	Inexpensive gnawing substrate; easily replaced during cage changes.
Cardboard tunnel	Structural	20	$0.30	$6.00	14d	Reduces aggression in group-housed males by providing escape routes (Van Loo et al. 2001).

When to use

Planning enrichment purchases for new or expanding facilities
Budgeting enrichment costs for grant proposals
Ensuring AAALAC compliance for enrichment requirements
Generating enrichment shopping lists for procurement

Do not use for

Enrichment for non-rodent species (primates, rabbits, fish)
Behavioral testing enrichment (which may confound experiments)
Enrichment scheduling and compliance tracking (use ConductColony)

Pearl

Start with nesting material — it has the strongest evidence base and the lowest cost per cage.

Pearl

Include at least one item from each category to satisfy AAALAC enrichment requirements comprehensively.

Pitfall

Avoid cedar or pine shavings as gnawing material — aromatic hydrocarbons are hepatotoxic in rodents.

Pitfall

Foraging enrichment with high-fat treats (seeds) can confound metabolic studies. Check with your PI before adding foraging items to metabolic study cages.

Method

Items are ranked by monthly cost per cage (unit_cost $\times$ qty_per_cage $\times$ 30 / replacement_days). The lowest-cost item per category is selected. Breeding cages receive +1 nesting unit. Single-housed cages receive +1 structural unit per AAALAC guidelines. Budget is compared against total cost to flag overages.

Validated

Last validated 2026-04-08. Calculations are designed for planning and documentation support; verify procurement decisions against manufacturer specifications or institutional SOPs.

How to cite

How to Cite

ConductScience Enrichment Item Planner (v1.19.0). ConductScience. https://conductscience.com/tools/enrichment-item-planner

Hutchinson E, et al. Environmental enrichment for laboratory rodents. ILAR J. 2005;46(2):148-161.

Hess SE, et al. Home improvement: C57BL/6J mice given more naturalistic nesting materials build better nests. JAALAS. 2008;47(6):25-31.

Evidence-Based Enrichment for Laboratory Rodents

Environmental enrichment is a legal and ethical requirement for laboratory animal housing. The scientific evidence supports specific enrichment strategies:

Nesting material: Cotton nestlets or shredded paper reduce corticosterone levels and improve thermoregulation. Breeding females with nesting material show better pup survival rates. Hess et al. (2008) demonstrated that nesting material is the single most impactful enrichment for mice.

Gnawing objects: Rodent incisors grow continuously. Without gnawing substrates, dental malocclusion can occur, causing pain and inability to eat. Aspen wood blocks are preferred; avoid cedar and pine (aromatic hydrocarbons are hepatotoxic).

Foraging enrichment: Scattering small amounts of sunflower seeds or other treats promotes species-typical foraging behavior without significantly altering body weight or experimental outcomes (Hutchinson et al. 2005).

Structural enrichment: Shelters (igloos, tunnels) reduce aggression in group-housed males by providing escape routes. Red-tinted polycarbonate provides darkness while allowing staff observation (Sherwin 2007).

Frequently asked

325

Free tools

1,200+

Institutions

100%

Client-side

Uploads required

Next steps

App

Enrichment Item Planner.

Calculator

Facility Setup

Enrichment Categories

Shopping List

Pearl

Pearl

Pitfall

Pitfall

Method

Validated

How to cite

How to Cite

Evidence-Based Enrichment for Laboratory Rodents

Frequently asked

Next steps

ConductColony

3Rs Justification Builder

Cage Census Capacity Planner

IACUC Budget Estimator