Transcervical bovine embryo transfer with Japanese metal AI instrument

Embryos were non-surgically recovered from superovulated donors. Two trials of ipsilateral single embryo transfer were performed with the Japanese AI instrument.For the first trial, neither the AI instrument nor the cervical expander were ensheathed. The overall pregnancy rate was 33.3 % ($\text{22}\text{26}$). Pregnancy rates obtained from three groups with different media were almost identical.In the second trial, both the AI instrument and the cervical expander were covered with a paper sheath to minimize uterine infection. The overall pregnancy rate after the second trial was 59.1 % ($\text{13}\text{22}$).