2.1. Recipients
Embryos were transferred to heifers and primiparous and multiparous Ayrshire and Holstein cows. The numbers of breeding attempts, as well as the parity and breed of recipients, are shown in Table 1. The breed and parity of the recipients are expressed in similar proportions for both embryo types. Likewise, the reproductive history of heifers and cows after the previous calving was similar for both groups of recipients.