Effect of Insemination Frequency and Type of Semen on Quantity and Quality of <i>In vivo</i> Produced Embryos from Ethiopian Boran Heifers

The use of proper superovulation technique, types of semen, frequency of artificial insemination, health condition of cattle and type of breeds are some of the common factors that directly affects the success of embryo transfer programmes. Therefore, this study was conducted to evaluate effects of AI frequency and semen type on quantity and quality of in vivo produced embryos in Ethiopian Boran heifers. In this study, Randomized Experimental Design was used in which 12 donor Boran heifers were super ovulated and embryos were collected. Donors were randomly allocated to two experimental groups: Group-one-6 donors were inseminated two times (3 donors each with conventional and sexed semen) at 12 and 18 hrs interval whereas in group-two-6 donors were inseminated three times (3 donors each with conventional and sexed semen) at 12, 17 and 22 hrs interval. The results of the study showed that mean number of 7.2 ± 1.9 and 9.0 ± 2.5 for CL and 2.2 ± 0.7 and 5.7 ± 1.5 for UOF were counted from donors grouped under two and three times AI frequency. Mean number of CL and UOF counted from donors grouped under conventional and sexed semen treatment were 9.0 ± 2.8 and 7.2 ± 1.45; 4.8 ± 1.8 and 3.0 ± 0.8, respectively. The number of CL and UOF counted from donors under two and three times AI and conventional and sexed semen treatment were not significantly (p > 0.05) different. Mean number of total flush output counted from donors grouped under two and three times AI frequency were 3.5 ± 0.43 and 7.3 ± 2.2, respectively. For conventional and sexed semen insemination, mean number of total flush output counted from donors were 7.00 ± 1.93 and 3.8 ± 1.35, respectively. Mean number of UFO counted from donors under two and three times AI were 2.3 ± 1.4; 2.7 ± 1.3 and Mean number of UFO counted from donors under conventional and sexed semen insemination were 3.5 ± 1.15; 1.5 ± 0.6, respectively. No significant (P>0.05) difference was observed between AI frequencies and semen types in terms of total flush output, number of transferable and non-transferable embryos as well as UFOs recovered from Boran heifer donors. The present findings demonstrated that inseminating Ethiopian Boran heifers two and three times both with sexed and conventional semen did not affect embryo quality and quantity produced in vivo from donors.