Effects of low-molecular-weight fractions (LMWF) from milk, egg yolk, and seminal plasma on freezability of bovine spermatozoa.
The effects of the dialyzable fractions from bovine seminal plasma, egg yolk, and milk and of two buffer systems (TEST and sodium citrate) on post-thaw sperm motility were studied. Each basic salt solution was used in the experimental design. These solutions were used as extender systems in combination with egg yolk and glycerol. After collection, semen samples were extended (1:20), cooled to 5 degrees C in 1.5 hr, and frozen in 0.5-cc French straws after 3 hr of equilibration. Post-thaw samples were assayed for percentage of motile cells immediately after thawing and after 4 hr of incubation at room temperature (22 degrees C). Egg yolk (25%) provided the same protection as did the combination of colloidal material present in the skim milk-yolk extenders. The use of TEST as a buffer provided significantly higher (P less than 0.01) sperm post-thaw motility than milk salts or Na citrate. Sperm survival in extenders containing high concentrations of seminal plasma and/or egg yolk salts was significantly lower (P less than 0.01). Spermatozoa frozen in the presence of 6% glycerol resulted in sperm motility significantly (P less than 0.05) higher than that of spermatozoa frozen with 3% glycerol. However, no difference was observed between these two concentrations when TEST solution was used.
D000818:Animals; D002417:Cattle; D003102:Colloids; D004530:Egg Yolk; D005615:Freezing; D008297:Male; D008892:Milk / Q000502:physiology*; D008970:Molecular Weight; D012661:Semen / Q000502:physiology*; D013094:Spermatozoa / Q000166:cytology* / Q000187:drug effects; D014020:Tissue Extracts / Q000494:pharmacology*; D014021:Tissue Preservation / Q000379:methods*
D003102:Colloids; D014020:Tissue Extracts