Livestock Studies 1991, Vol 31, Num, 1-2     (Pages: 096-110)

Freezing of Bovine Embrvo

Hüseyin SUNGUR 1 ,Nafiz YURDAYDIN 2

1 Vet. Hek., PUGEM Araştırma Dairesi, Hayvan Yetiştirme ve Islah Şb. Md.
2 Yrd. Doç. Dr., A.Ü. Veteriner Fakültesi, Reprodüksiyon ve Sun'i Tohumlama Bilim Dalı, ANKARA
- For last ten years, The developments recorded on the biotechnology have facilitated the control of reproduction processes in the animal husbandry and the obtained results have drawn attention at all times.

Embryo transferring means the transferring of embryo to uterus of another female by using surgical and non-surgical methods and the completing of all the gestation period in this uterus, after the taking out of this embryo which is at earlier phase from donor female. Putting of embryo transferring process on the practice with a 50 % of gestation success have focused all the interests on female brooders. As while 50 % of genetic can be controlled with a bull having a good performance, 100 % of genetic is possible to control with embryo. The above-mentioned developments on the biotechnology have obliged the animal breeders to take both female and male brooders in to the consideration.

Embryo transferring makes possible to obtain a lot of calves from superior quality female animals which not oblige to carry their own fetus during all the period of gestation. Suckling mother has not any influence on calve which she carries. But, receipents transfers the immunities against to some diseases to calve.

As known, embryo transferring is applied together with superovulation process. The purpose of superovulation process is to provide to be produced ovum more than one during one cyclus. It is problem that superovulation exhibits a large variation. There fore, it is impossible to estimate amount of ovum or embryo to be obtained. Superovulation may not form in some cows, hovever superovulation more than 15 -20 % may form in some cows. Reaction of same cow to superovulation may be different in varioos times.

These factors make harder estimation of mother amount to be synchronized and caused to loss of embryo in sometimes.

Embryo transferring provided advantadges such as a considerable low transport cost and lower disease risks for costomers.

In this respect, since 1970's, embryo transferring has being considered as part of programmes relating to genetical improvements and research on the methods of embryo freezing have being intensed. Keywords :