Proteins in stallion seminal plasma
Amann, R.P.; Cristanelli, M.J.; Squires, E.L.
Journal of Reproduction and Fertility. Supplement 35: 113-120
1987
ISSN/ISBN: 0449-3087 PMID: 3479566 Document Number: 296926
For 8 ejaculates from each of 17 stallions, seminal plasma was stored at -20 degrees C and spermatozoa were cryopreserved. Based on post-thawing sperm motility, seminal plasma samples from 7 stallions (2 good, 3 variable and 2 of poor sperm motility) were selected for measurement of electrolytes, protein content and analysis by sodium dodecylsulphate gel-electrophoresis (10% gel, Coomassie blue stain). The seminal plasma concentrations of sodium, potassium, calcium and chloride but not of phosphorus or protein, varied (P<0.05) among stallions. 27 proteins, of 13 000-122 000 molecular weight, were detected in the seminal plasma. There was a difference (P<0.05) amongst stallions in the proportion of ejaculates containing 13 of the 27 proteins. However, only for proteins 23 and 26 was there a significant correlation between the relative amount of protein and sperm motility (0, 30 or 60 min after thawing; 0.42-0.50). These correlation coefficients, and those with the potassium concentration, were too low to have predictive value. Therefore, although an effect of a minor protein cannot be excluded, variation in the relative amounts of major proteins in seminal plasma probably is not a cause of differences in post-thawing motility of stallion spermatozoa.