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Adult male mice excrete a urinary chemosignal that accelerates puberty in females, whereas group-housed female mice excrete a urinary chemosignal that delays puberty in young females. We found that: (1) the excretion of the puberty-acceleration chemosignal by males persisted in the absence of the vomeronasal organs and (2) the puberty-delay chemosignal was not present in the urine of group-housed females whose vomeronasal organs had been surgically removed (VNX), but was present in the urine of group-housed females subjected to sham surgery (SHAM). These results suggest that in males, vomeronasal chemoreception does not affect the excretion of the puberty-acceleration chemosignal, but that in females, the vomeronasal organ receives chemosignals that influence the excretion of the puberty-delay chemosignal. Additionally, we found no difference between SHAM and VNX females in rates of conception, litter size, pup growth, pup recognition, or maternal behavior, indicating that normal maternal processes are expressed in the absence of an intact accessory olfactory system.

Detection of reproductive status from chemical signals at sandbathing loci was examined in Merriam's kangaroo rat. Castrated and intact males were attracted similarly to the sandbathing loci of four classes of scent donors: intact males, castrated males, estrous females, and nonestrous females. This suggested that reproductive status was not communicated to males at sandbathing loci. In a control test, castrated males were attracted to disturbed sand that contained no olfactory cues whereas intact males were not. Castration caused a significant decrease in the size of a specialized sebaceous gland on the dorsum. Castration did not affect total pelage lipids, however, indicating that lipid-producing cells have a baseline level of secretion that is necessary for pelage maintenance.