The challenge is to collect samples from individual rodents while avoiding stress-associated effects from the sampling method itself. Here we present an apparatus and protocol allowing routine repeated collection of an individual rodent's fresh fecal samples without noticeable disturbance of any of the study animals; The apparatus consists of 1 central and 4 lateral compartments.
The experimental animal was allowed to enter a lateral compartment voluntarily, where it remained for the short (4 h) period necessary for sample collection before rejoining the rest of the group. The results confirmed the repeatability of the assessment of baseline levels of glucocorticoid metabolites.
Moreover, keeping the animals in our experimental apparatus did not induce any increase in the levels of glucocorticoid metabolites, even when isolation in the compartment was relatively prolonged.