Copulatory performances of penile desensitized male rats as a function of prior social and sexual experience

Male rats were reared under one of the following conditions from 14 days of age: (1) Isolation (raised in individual cages); (2) Contact isolation (isolation except for Days 40–60 when two females lived close to the male, separated only by a screen); (3) Cohabition with males prepuberally (males together between Days 14 and 40); (4) Cohabition with males postpuberally (males together between Days 40 and 60); or (5) Cohabition with females (male together with females between Days 40 and 60). When 75 days old, the rats were subjected to penile deafferentation by pudendal nerve transection and tested for masculine sexual behavior. The Group 5 males showed more intromission patterns than those of Groups 1, 2, and 3 and more ejaculation patterns than those of Groups 1, 2, 3, and 4. It was concluded that postpuberal heterosexual experience controls the expression of sexual behavior in two ways: (a) by increasing the readiness to initiate mounting behavior and (b) by facilitating the display of a complete mating pattern.