Submitted to: American Society of Animal Science Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: April 12, 2002
Publication Date: N/A
Technical Abstract: The cell volume excursion associated with exposure to osmotic stress motility loss and increased death in porcine spermatozoa. This experiment was done to determine effects of osmotic stress and bovine serum albumin (BSA) treatments on sperm viability and motion characteristic. Semen from ten boars, extended in Beltsville Thawing Solution, was incubated at 38 C for five min in phosphate-buffered saline (PBS) with or without 0.3% BSA a final osmolalities ranging from 80 to 1170 mOsmoles/kg (mOsm) and then returned to isosmotic conditions. The percent motile sperm (MOT) and measures of sperm motion were determined using a Hobson Sperm Tracker, and the proportion of sperm cells with plasma membrane integrity (PMI) was determined by flow cytometric analysis of the fluorescence of the nuclear stains SYBR-14 and propidium iodide. MOT decreased significantly (P</= 0.05) as osmolality of sperm treatments decreased or increased outside of a arange of 290 to 340 mOsm. PMI and motion parameters were more osmotically tolerant than MOT showing a low incidence of statistically significant change in the range of 290-430 mOsm. The presence of BSA in the anisosmotic PBS solutions was capable of reducing the loss of motility increasing MOT by 13-14 percentage points to 75.3% and at 290 mOsm and 78.2% at 340 mOsm, and increased the following sperm motion parameters: curvilinear velocity (15%), average path velocity (26%), straight line velocity (60%), beat cross frequency (33%), and percent straight line distance (33%) in the range of 215-430 mOsm. The presence of BSA had no significant effect on PMI or amplitude of lateral head displacement. While hypo- and hyperosmotic stress kills many boar spermatozoa, a subpopulation in each ejaculate was capable of maintaining viability and normal motion characteristics.