Use of 131I sperm labelling to study distribution and migration of spermatozoa in the genital tract of female sheep, following artifical insemination. 2

Fresh ram sperma or sperm-free seminal plasma, labelled with 131I was intracervically applied to 7 ewes with an estrus synchronised by means of PGF/sub 2α/. The animals were slaughtered at different dates after insemination. The genital tract of the sheep was cut into 14 sections which were all measured for radioactivity. Seminal plasma was found to have undergone transcervical and transuterine passage, which produced evidence to the effect that the uterine cervix of sheep was permeable to seminal plasma. 'Barrier effects' of the cervix were of different strength, depending on individuals. Labelled sperma was quantitatively detected also from the upper genital regions, which seemed to support the assumption that sperm storage function had to be attributed not only to the uterine cervix of sheep, but also to the uterotubal canal. Asymmetry was observed in distribution between left and right uterus cornua and oviducts. (author)