Cage size preference in rats in the laboratory

Area of Science:

• Animal Welfare Science
• Laboratory Animal Science
• Ethology

Background:

• Enclosure size is critical for animal welfare, yet enrichment studies often overlook space allowance.
• Empirical data on laboratory rats' specific spatial needs is lacking.
• Previous assumptions suggested rats have minimal requirements for increased cage space.

Purpose of the Study:

• To investigate the spatial preferences of laboratory rats.
• To provide empirical evidence regarding rats' need for larger enclosures.
• To assess the impact of social housing on space preference in rats.

Main Methods:

• Utilized a T-maze choice paradigm with 5 male and 5 female albino rats.
• Measured preferences between two distinct cage sizes (540 cm² vs. 1,620 cm²).
• Assessed dwelling time in chosen cages and repeated preference tests with social housing (4 familiar cage mates).

Main Results:

• Rats demonstrated a statistically significant preference for the larger cage (1,620 cm²).
• This preference for increased space remained consistent regardless of the presence of familiar cage mates.
• Social housing did not diminish the preference for larger enclosures.

Conclusions:

• Laboratory rats exhibit a clear preference for larger enclosures, indicating a need for greater space allowance.
• The findings challenge previous notions about rats' minimal spatial requirements.
• Recommendations include providing larger housing for rats, which can be socially accommodated.