Electrophoretic and gel filtration behaviour of boar seminal plasma proteins before and after removal of accessory sex glands.

The origins of the major proteins of boar seminal plasma were identified using starch gel electrophoresis, gel filtration on Sephadex G-200 and surgical removal of various accessory sex glands. Seminal vesicular secretion accounted for all the major proteins in seminal plasma which migrated to the cathode. Bulbo-urethral proteins could not be detected electrophoretically or by gel filtration. Prostatic\x=req-\ urethral fluid contained at least one protein which migrated to the anode and was not ofserum origin. Secretions from the epididymis and/or testis contained at least two proteins which migrated to the anode that were eventually voided in the seminal plasma of the ejaculate. Boar seminal plasma separated on Sephadex G-200 into three major peaks corresponding to molecular weights of approximately 155,000 (Peak B), 55,000 (Peak A) and 34,000 (Peak C). Peak A proteins were primarilyofseminal vesicular origin, while Peak B proteins were primarily of epididymal or testicular origin. Peak C consisted of proteins from all regions of the reproductive tract. Haemagglutinating activity was located between Peaks A and B, associated with molecules of approximately 68,000 molecular weight, and was absent after removal of the seminal vesicles.