Comparison of the longevity of motility of stallion spermatozoa incubated at 38 degrees C in different capacitating media and containers

This study was designed to compare the effects of different media and conta iners on longevity of motility of spermatozoa during in vitro incubation at 38 degrees C in either air or 5% CO2 atmosphere. Three ejaculates were col lected from each of 4 stallions. The media tested were skim milk-glucose, m odified Krebs/Ringer and Hank's salts solution for incubation in an air atm osphere, and modified Krebs/Ringer and Brackett and Oliphant (BO) defined m edium for incubation in a 5% CO2 atmosphere. All samples were incubated in 5-mL borosilicate glass tubes filled with 3 mL of extended spermatozoa, 5-m L borosilicate tubes filled with 6 mL (topped) of extended spermatozoa, 35- mm Petri dishes filled with 3 mL of extended spermatozoa and 35-mm Petri di shes with 200-mu L microdroplets of extended spermatozoa under sterile mine ral oil. For all treatments, individual samples were removed at 2, 4, 6 and 12 h of incubation to determine the percentage of motile cells. Overall, s permatozoa incubated in Petri dishes in both 3-mL and microdroplet treatmen ts had significantly higher motility than those incubated in glass tubes (P <0.01). At 6 and 12 h of incubation in Petri dishes, progressive motility w as significantly higher for spermatozoa extended in the Hank's salts soluti on than in the other media. Both the medium and container used significantl y affected the longevity of motility of spermatozoa incubated at 38 degrees C. (C) 1999 by Elsevier Science Inc.