Systematic interrelationship of mating, vaginal plug position, and sperm transport in the rat

Role of striated penile muscles in penile reflexes, copulation, and induction of pregnancy in the rat

“…number of pre-ejaculatory intromission patterns displayed by experimental (8-08 ± 0-74) and control (7-50 ± 0-65) males did not differ significantly (t = 0-59 Adler, 1978). The ejaculated plug also needs to be deposited firmly against the cervix to potentiate entry of spermatozoa into the uterus and to facilitate sperm transport (Blandau, 1945;Matthews & Adler, 1978). The number of intromissions and the other copulatory measures of the experimental males were similar to those of controls, so that at least some of the females may have been made pseudopregnant.…”

“…When the male rat ejaculates, the cup forms at or just before the time of maximum penile extension, and just before the plug leaves the urethral meatus (Pollak & Sachs, 1976). The timing and configuration of the cup make it ideal for exposing the cervical lumina, pushing the plug firmly against, and partly through, the cervix, and leaving the plug in place there (Blandau, 1945;Pollak & Sachs, 1976;Matthews & Adler, 1978). If the cup were unable to form, the glans would continue to grip the coagulated plug, withdrawing a larger portion of its proximal end from the vagina, and possibly dislodging its distal end from the cervix.…”

Pharmacological analysis of male rat sexual behavior

“…Briefly, intense erections that result in a flanng of the glans penis ("cups") are associated with the placement of the ejaculatory plug against the cervix. A tight fitting plug ensures adequate sperm transport and mhtbits plug displacement by another male [145]. Dorsiflexions of the glans penis ("flips") are associated with gaining a proper onentation for penile insertion during copulatory mounts [191,192].…”

Genetic and phenotypic influences on copulatory plug survival in mice

“…A large body of data suggest that plugs evolved to impede remating by females (Mosig and Dewsbury, 1970;Martan and Shepherd, 1976;Hartung and Dewsbury, 1978;Voss, 1979), although additional plug functions may include ejaculate transport through the female's reproductive tract (Blandau, 1945a,b,;Matthews and Adler, 1978;Toner et al, 1987;Carballada and Esponda, 1992;Rogers et al, 2009), stimulation required for proper implantation and pregnancy (Ball, 1934;Dean, 2013) and slow release of sperm (Asdell, 1946).…”