Conspecific urine marking in male-female pairs of laboratory rats.
Male-female pairs of rats were observed during social interactions for conspecific markings where an animal deposits urine on the body of a second animal. Injections of sodium fluorescein were used to change urinary color and provide a visible mark on the back of a conspecific. The general hypothesis tested in the three experiments was that a female would mark males differently dependent upon her hormonal status and upon the relative hormonal integrity of the males. Results of Experiment 1 were that males marked females more frequently than vice versa and female marking decreased during her estrus. Moreover, a diestrous female marked an aggressive male more than she marked a non-aggressive male (Experiment 2), and a diestrous female marked a castrated male receiving 800 micrograms testosterone propionate (TP) injections more copiously than she marked a castrated male receiving 200 micrograms TP injections (Experiment 3). Finally, aggressive and non-aggressive males marked females similarly, though the 800 micrograms TP males marked females more than the 200 micrograms TP males. These data were compared with findings from research on environmental marking in rodents, and an hypothesis was suggested that female rats use conspecific marking to identify and select males with preferred behavioral and endocrine characteristics.
D000374:Aggression / Q000502:physiology; D000818:Animals; D004971:Estrus; D005260:Female; D008297:Male; D010675:Pheromones / Q000652:urine*; D011247:Pregnancy; D051381:Rats; D011919:Rats, Inbred Strains; D012724:Sex Attractants / Q000652:urine*; D012726:Sexual Behavior, Animal / Q000502:physiology*; D012931:Social Environment; D013739:Testosterone / Q000097:blood
D010675:Pheromones; D012724:Sex Attractants; D013739:Testosterone