Rapid transport of seminal immunoglobulin to distal parts of the female reproductive tract in rabbits.

Bucks immunized with the bacteriophage-cloning vector fd-tet display strong humoral seminal immunity of 1.5 x 10(6) fd-tet neutralizing units (nu) ml-1. We used this model to study the distribution of seminal immunoglobulin in the female reproductive tract after copulation and artificial insemination. In contrast to artificial insemination, significant (P < 0.01) amounts (147 nu ml-1, i.e. about 1.25 x 10(-4) input ejaculate) of neutralizing activity reached the uterus within 20 min of a single copulation, which is evidence for rapid transport of seminal plasma to distal parts of the tract. Oviducts were also quickly impregnated with antibodies to fd-tet, which persist in the distal compartments for at least 24 h.