MOUNTING AND INTROMISSION
1. What are some causes for mounting failures?
2. Define intromission. Which domestic species has the longest and which has the shortest duration of intromission? What are causes for intromission failures?
Mounting is the stance assumed by the male by which the penis is brought into apposition with the vulva of the female.
Successful mounting must be preceded by a receptive stance on the part of the female. Failures in mounting are encountered when there are injuries, weakness, or soreness in the hindlimbs of the male.Introduction of the penis into the vagina and its maintenance within the vagina during coitus is known as intromission. Pelvic thrusts assisted by the abdominal muscles assist penetration of the penis into the vagina. The duration of intromission varies among species: it is shortest for the bull and ram and longest for the boar. Failures of intromission occur in some animals; causes include phimosis (constriction of the preputial orifice), hematoma of the penis (as in the bull), and congenital deformities. Final distention of the penis does not occur in the dog until after intromission. It is presumed that intromission is facilitated in the dog by the presence of the os penis (penis bone.
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