It is well known that male wild boars (Sus scrofa) are usually solitary. However, during the mating season, they compete for females which may bias their mate choice toward some of the males breed. In order to determinate whether or not a precopulatory choice occurs in captivity, 18 yorklandrace multiparous females (Y/N) were mated with three males belonging to three breeds: yorkshire (Y/Y), yorklandrace (Y/N), landrace (N/N). Copulation preference, precopulatory and copulatory behaviors, as well as the female-female interactions were registered. During the precopulatory phase, in terms of time, the Y/N male received more female attention (53.7%) than the other males. Additionally, Y/Y male more frequently displayed behaviors as "teeth chattering" (83.33%), "vocalization" (56.52%) and "trumping" (64%). "Vagina smelling" was more frequently displayed by N/N male (48%) and "biting" by Y/N male (60%). During the copulation, Y/N male displayed significantly more "nose-vagina" behavior (41%) and N/N male, the "vocalization" behavior (46.9%). Four females recently copulated by males, were mounted by other females in estrus producing an expulsion of both the seminal tap and the ejaculate. The results show a strong behavioral competition between the three males and a female precopulatory preference by the heterozygous Y/N male. A possible explanation to this phenomenon is that the Y/N male odoripherous secretions from both, salivary and prepucial glands; carry information about his genetic quality. Female-female mounting is probably an expression of intra-sexual competition, reducing chances for fertilization.
