The Effects of Conventional Semen, Sexed-Semen and Embryo Transfer on Pregnancy Rate in Dairy Cows

Abstract

In this study, it was aimed to detect the effects of conventional semen, sexed-semen and embryo transfer on pregnancy rates in dairy Holstein cows. In the study, a total of 139 healthy cows with the serum progesterone > 8 ng/ml were used as animal material. Estrus synchronization protocol was applied and cows were divided into three different groups as conventional semen group (G1, n=46), sexed semen group (G2, n=47), and embryo transfer group (G3, n=46) considering age, body condition score, lactation number, and live weight. Cows in G1 and G2 were inseminated with conventional semen and sexed-semen respectively. Embryo transfer was performed to cows in Group 3 (n=46) 7th day after estrus. SPSS was used for statistical evaluation of results (SPSS 23, Chicago, IL, USA). Pregnancies were detected 30th and 60th day after artificial insemination and embryo transfer. Pregnancy rates were detected as %50, %46,8 and %69,56 in G1, G2, and G3 respectively on 30th day. On 60th day, however, pregnancy rates were %45.60, %42.55 and %67.39 in G1, G2, and G3 respectively due to embryonic losses. The pregnancy rate was significantly higher in the embryo transfer group (G3) compared to the conventional semen (G1) and sexed-semen (G2) group (p0.05). Findings led to the conclusion that higher serum progesterone level may increase pregnancy rate in cattle. In addition, embryo transfer may be more advantageous than conventional and sexed-semen to increase genetic progress in dairy cattle.