142 Methods to concentrate stallion semen for storage

Abstract

It has been demonstrated that removal of seminal plasma and resuspension of the sperm pellet in various diluents will improve the post storage motility of spermatozoa from some stallions. This normally involves centrifugation. However, a sperm filtering device marketed by Botupharma (Phoenix, AZ) allows removal of seminal plasma without use of a centrifuge. This study was designed with the objective of comparing spermatozoa recovery rates using this device vs. centrifugation with and without a cushion. Thirteen ejaculates were collected from 3 Quarter Horse stallions. Before treatment aliquots were diluted with Dulbecco's modified PBS at a dilution rate of 1:1. For the 2 centrifugation treatments, 12 mL of the diluted semen was placed in a 15 mL conical bottom tube and centrifuged for at 1000g for 20 min with Red Cushion, (Botupharma), or at 400g for 10 mintues without a cushion. Aliquots for the third treatment were also diluted 1:1 and 20mL of the solution and poured into a SpermFilter (Botupharma) for separation. To determine % of sperm recovered, the concentration of aliquots before and after filtration or centrifugation was measured using a densimeter device (ARS, Chino, CA). Data were analyzed by one-way ANOVA with Tukey's test used for pairwise comparisons. Average % recovery rates were 69.4%, and 60.9% for aliquots centrifuged without and with a cushion as compared with 77.6% for the SpermFilter treatment. In this experiment the % recovery was lower (P < 0.02) for those aliquots which were centrifuged with Red Cushion compared with those separated with the SpermFilter. These results could differ if the same procedures were compared with a different technician. Furthermore, because of the diluent used following separation no attempt was made to compare motility following the separation procedures.