EVALUATING THE RELATIONSHIP BETWEEN ULTRASONOGRAPHIC PARAMETERS AND SEMEN QUALITY IN ANGORA BUCKS

Introduction Since male fertility is essential for successful breeding in livestock, the usage of a non-invasive tool as ultrasonographic (US) imaging capable to evaluate reproductive capacity in Angora bucks could be a useful and reliable method. Objective This study aims to investigate the association between ultrasonographic parameters and semen quality in Angora bucks. Materials and methods Thirty-six bucks were categorized into three groups based on the Computer-Aided Ultrasonography (CAU) appearance of the testicular parenchyma, defined by the Testicular echotexture Index (TEI) which reflects the extent of the tissue changes observed in the testicles through ultrasound. In the first phase of the experiment scrotal circumference, testicular volume, and pixel grey intensity (PGI) of the testis and vesicular glands were evaluated. Semen was collected using an artificial vagina, evaluated for both fresh and post-thaw characteristics. In the second phase, semen was collected via transrectal massage and compared with transrectal ultrasonographic findings. Results Group 3 exhibited the highest scrotal circumference and testicular volume, while group 2 showed best fresh and post-thaw semen parameters including the concentration and motility. Semen collected via transrectal massage showed lower motility and viability comparing to artificial vagina, emphasizing the impact of collection method. While scrotal circumference and testicular volume did not differ significantly between groups in rectal collections, testicular PGI was highest in Group 3. Conclusion Although the testicular echotexture index (TEI) is not a precise diagnostic tool, higher echogenicity negatively affects sperm quality, particularly post-thaw motility and viability. Accessory gland ultrasonography, especially of vesicular gland and bulbourethral glands, may support fertility assessment. Ultrasonography provides insights into semen quality and freezeability, with PGI and Computerized-aid ultrasonography as potential diagnostic markers for breeding soundness.