Phospholipid and cholesterol profiles from chicken seminal components during in vitro storage at 5 C

Two experiments were conducted with undiluted chicken semen to determine if fluctuations in endogenous phospholipids and cholesterol might relate to loss of fertilizing capacity which accompanies in vitro storage for 24 hr at 5 C. The following parameters were monitored quantitatively: individual seminal plasma and spermatozoal phospholipids, spermatozoal cholesterol to phospholipid molar ratios, and spermatozoal cholesterol mole percent. After storage for various periods, total lipids were extracted with chloroform:methanol (2:1, v/v). Total phospholipids were obtained by precipitation with cold acetone and further resolved into individual components by thin layer chromatography. All phospholipids and cholesterol were quantitated spectrophotometrically. Spermatozoal phospholipids, the spermatozoal molar ratio of cholesterol to phospholipid, and the spermatozoal mole percent of cholesterol remained essentially the same throughout the 24-hr storage period. Seminal plasma phosphatidylethanolamine also did not fluctuate significantly during the storage period. However, the phosphatidylcholine and the phosphatidylserine-inositol fractions from the seminal plasma appeared to increase with time.