Habituation to individual odors occurs following brief, widely-spaced presentations

The possibility that male guinea pigs (Cavia porcellus) habituate to individual female conspecific urine odors following very brief, widely-spaced presentations was tested. On day 1 of test week 1, each male was exposed for 2 min to urine of one female, on day 3 to urine of a second female and on day 5 to urine of a third female. The number of seconds investigating the samples was recorded. This same procedure was repeated for 3 more weeks. On weeks 5 through 8, three novel females provided urine samples for testing which was conducted in an identical manner. On week 9, urine samples of the original 3 donors was tested. Results indicated that male guinea pigs habituated to urine odors presented for only 2 min 7 days apart and that dishabituation occurred following presentation of samples from novel donors. These data demonstrate an exquisite sensitivity to female urine odors, a long memory for individual differences in these odors, and a consistency over time in the composition of an individual's urine.