Abstract

The role of specific inorganic ions in the maintenance of ram sperm motility in a chemically defined ram semen diluent (RSD-1) was examined. A preliminary experiment identified that magnesium was required to maintain motility. Significant treatment and incubation effects were observed for all motility parameters (P<.05). RSD-1 (treatment T1) was modified to provide a series of treatments. Effects measured were the substitution of MgCl2 (T2) or MgSO4 (T3) and the elimination of KH2PO4 (T4) or NaHCO3 (T5). A total of 10 ejaculates were analysed using the Hobson Sperm Tracker (HST) over a period of 7 days. Semen was cooled to 15 C after dilution with treatment diluents and reheated to 38 C after 1 hr and 5 days storage. Motility was measured after incubation at 38 C for 0, 24, and 48 hours. Treatments had a significant (P<0.001) effect on the velocity parameters and the percentage of motile sperm. Treatments T4 and T5 had greatest depression in motility parameters with fresh semen while T5 also had an effect with stored sperm. Substitution of the MgSO4 (T3) reduced the velocity parameters in the fresh semen e.g. mean Curvilinear velocity (VCL) values (

RM, Briggs, GC Upreti, JF Smith, and DM Duganzich

Proceedings of the New Zealand Society of Animal Production, Volume 56, , 353-354, 1996