Ram semen evaluation: Development and efficiency of modern techniques

Although the application of modern technologies and techniques in ram semen evaluation is not as widespread as in domesticated animal species, developments have been reported. Improvements in extenders and cryo-protectants have contributed to extended ram semen preservation and better results of ovine artificial insemination. For these reasons, semen evaluation process offering high accuracy and reliability of the results is needed more than in the past. Major advancements have been made on ram semen analysis by using computer assisted semen analyzers. Moreover, evaluation of sperm function in depth as the estimation of sperm mitochondrial status, sperm nucleus chromatin integrity and sperm ability to bind and/or fertilize an oocyte have recently been included to ram semen assessment. This review emphasizes to recent development in these technologies that start to show satisfactory diagnostic value for ram semen evaluation, as well as to their relation with field fertility.