Assessment of oviduct potency in the cow.

A test of oviduct patency was developed, based on instillation of dye to the uterine horn through a two-way catheter. In 23 cows, two cases of bilateral and five cases of unilateral blockage were detected. Of 69 cow genital tracts collected from an abattoir, nine of 138 oviducts (7 per cent) did not permit the passage of dye. Fourteen of the remaining oviducts were found to blocked using a suspension of 80 micrometer pollen grains. This suggested that some animals showing patency to the dye test in vivo may in fact have abnormalities of the oviduct sufficient to prevent the passage of the ovum. In five cows, superovulation and embryo recovery were carried out as an investigation of oviduct patency and function. Although in one of the five cows, subsequently found to have a blocked oviduct, no embryos were recovered, ambiguous results were obtained in the other animals. The unpredictable response to superovulation may limit the application of this latter technique in investigation of oviduct patency and function.