IN-VITRO FERTILIZATION IN HUNGARIAN GRAY CATTLE

Experiments have been performed to investigate the potential use of in vitro fertilization for the preservation of the endangered Hungarian Grey cattle. 1018 excellent quality oocytes from 167 ovaries of slaugh tered Hungarian Grey cows and heifers were matured. Out of 966 oocytes cocultivated with pre-test and swim-up selected Hungarian Grey frozen -thawed semen, 386 (39.9%) cleaved and 141 (14.6%) reached the morula- blastocyst stage on the 7th day of embryo culture (1.69 transferable e mbryos per animal). Some embryos were transferred into the uterine hor n of 10 natural cycling Hereford, Hungarian Red-spotted, Hungarian Red -spotted x Hereford recipients. Sixty days after transfer, 4 recipient s were diagnosed as being pregnant by ultrasonography (two multiple bi rths are expected); since then one calf has been born. Our results ind icate that the IVF method can be used for the preservation of endanger ed cattle breeds, reducing the losses caused by slaughter for various reasons.