The vas deferens count: a new accurate method for experimental measurement of testicular exocrine function.

Clinical and experimental measurement of fertility presents difficulties in technique and interpretation of results. This study compared a new concept, the vas deferens count (VDC), with the standard electroejaculation method as a means of measuring testicular sperm output. Seventy-five Wistar rats in three groups (control, orchidectomy, torsion) underwent VDC and electroejaculation fertility analyses. The VDC was successful in all cases and gave rise to results showing acceptable variance and, in addition, measured unilateral testicular exocrine function in each case. Electroejaculation was found to be a less satisfactory technique. The VDC is a simple and accurate technique for measuring testicular exocrine function in experimental animals.