Abstract
This scientific study assessed the semen quality of domestic Kazakh fat-tailed coarse-wool rams and foreign Dorper rams at Republican Center for Livestock Breeding “Asyl Tulik” and examined their effect on the fertility rate of Kazakh fat-tailed coarse-wool ewes at Akzhar Ondiris Agrofirma LLP, Pavlodar Region, Maysky District. The aim of the study was to compare the semen quality of domestic and foreign rams and to scientifically substantiate the effectiveness of their use in the artificial insemination of sheep. As a result of the study, the semen volume of Dorper rams was 1.50 ± 0.18 ml, the concentration was 3500 ± 320 × 10⁶/ml, and the motility was 80.2 ± 3.5%, whereas the semen volume of Kazakh fat-tailed coarse-wool rams was 1.25 ± 0.15 ml, the concentration was 2900 ± 280 × 10⁶/ml, and the motility was 70.4 ± 4.1%. The study demonstrated that semen quality directly affects the reproductive performance of rams. Upon completion of the study, the fertility rate of ewes inseminated with semen from Dorper rams was 107,6%, while that of ewes inseminated with semen from kazakh fat-tailed coarse-wool rams was 103,3%. It was found that Dorper rams exhibited better semen quality, and Kazakh fat-tailed coarse-wool ewes artificially inseminated with their semen showed higher fertility rates than those inseminated with semen from Kazakh fat-tailed coarse-wool rams.