Egg Transfer in the Cow: Pregnancy Rate and Egg Survival

The Agricultural Institute, Beldare, Galway, Ireland (Received 13th June 1974) Apart from the results reported by Rowson, Moor & Lawson (1969), Rowson, Lawson & Moor (1971) and Rowson, Lawson, Moor & Baker (1972), no data are available on pregnancy rates following the surgical transfer of fertilized cow eggs. Rowson et al. (1969) recorded a pregnancy rate of 91 % in a group of eleven heifers, each of which received either two or three fertilized eggs transferred to the uterine horn adjacent to the ovary carrying the corpus luteum. No incidence of twinning was recorded following these transfers. Rowson et al. (1971) reported a twinning rate of 50% following the transfer of one fertilized egg to each uterine horn in eighteen recipients. The total egg survival in this study was 61·1 %. When both the donor and recipient were in oestrus on the same day, however, the corresponding rates were 71·4%