The effects of sexual experience and frequency of testing on retention of copulatory behavior following castration in the male hamster

Abstract

Retention of copulatory behavior after castration was assessed by frequency of and latency to first mount and intromission in seven groups of male hamsters given 10-min tests with a sexually receptive female at weekly or longer intervals. Five groups were sexually experienced prior to castration; one group remained intact. The group receiving no precastrational sexual experience scored significantly lower on all measures. Experienced males show longer retention of copulatory behavior than inexperienced males. Animals tested weekly showed a significantly faster decline in copulatory behavior than animals tested at 3- or 6-week intervals. Males showed no change in nasal-nasal contact with the females as a result of sexual experience, castration, or frequency of testing; however, nasal-anal contact of male to female decreased significantly as a result of castration. Biting and tugging at the tail and hindquarters of the female increased following castration both in relation to duration of the castrate state and frequency of testing. The castrate sexually experienced group tested weekly spent from one-third to one-half of the entire test period in this behavior.