Quantitative studies were made of the distribution of spermatozoa and leucocytes in the female genital tract of mated goats and cows near the time of ovulation and of the leucocytes in the genital tract of unmated goat does at a similar time. In both species, the cervix appeared to act as a reservoir for spermatozoa. Spermatozoa were not uniformly distributed through the lumen of the cervix but tended to be aggregated in the vicinity of the cervical mucosa.
The presence of spermatozoa in the genital tract resulted in an increased number of leucocytes in the lumen of the uterus and cervix. In the cervix, the majority of the leucocytes occurred in the central mass of the mucus, this being consistent with the main invasion of the cervical mucus by the leucocytes taking place from the uterus. The resulting separation of spermatozoa and leucocytes in the cervix is probably an important factor in the survival of an adequate population of spermatozoa in the cervix of ruminants after mating.