Semen quality and quantity in a boar with a complex hydrocele

This case report concerns a 3.5-year-old Duroc boar with an enlargement of the left hemiscrotum. Sonography revealed multiple hypoechogenic cavities around the testis, indicating a complex hydrocele. An infectious origin of the hydrocele was excluded by laboratory tests. Repeated semen analysis by microscope, computer-assisted sperm analyzer, flow cytometric assessment, and sperm chromatin structure assay showed only a subtle increase in proportion of sperm with head deformities 7 weeks after first clinical signs were observed. Necropsy confirmed the sonographic findings. The left testis was only half the size of the right. Histological examination of the left testis revealed moderate interstitial fibrosis, and areas of calcification were found. Signs of spermatogenesis were detected in only a few areas. Analysis of semen production data showed that the number of sperm per ejaculate was lower for this boar at the age of 2.5 to 3.5 years than at the age of 1.5 to 2.5 years (P < .001). To our knowledge, this is the first report of a complex hydrocele in a boar in the context of semen quantity and quality.