Chapter 9.5. Multi-Tier Caging (2007)

LAREF [Laboratory Animal Refinement and Enrichment Forum]

Abstract

In a quantitative study I did on 20 pair-housed cynos, the animals spent 94 percent of their waking time in the upper part of the vertically arranged double cage. All food was given in the bottom section, yet the animals would bring the food to the upper part and consume it there. The monkeys preference along the gradient of height was unequivocal!I observed squirrel monkeys in vertically arranged double cages and also found that the animals clearly preferred the upper half of their cages. The only time they went to the bottom half was when they retrieved a toy or picked through the bedding for treats.When visiting facilities that have their pair-housed macaques kept in vertically arranged double-cages, I repeatedly got the impression that subordinate partners are disadvantaged in this caging system, with dominant animals preventing subordinates from spending as much time in the upper section as they would like to.