Decapacitation of boar spermatozoa

This thesis describes three studies that were completed to demonstrate the decapacitation ability of boar seminal plasma (SP) when added to incubated, cooled, and frozen-thawed (FT) boar spermatozoa. In the first study, chlortetracycline (CTC) staining analysis was used to investigate the effects of 20% (v/v) SP addition at different time points on the temporal pattern of capacitation in spermatozoa incubated at 39 C or cooled to 5 C and then rewarmed to 39 C. Seminal plasma was able to prevent and reverse capacitation in spermatozoa incubated in a capacitation-supporting environment as well as capacitation induced by cooling the spermatozoa to 5 C. In the second study, the addition of either 10 or 20% (v/v) SP to frozen boar spermatozoa at thawing were investigated using CTC analysis. The addition of either 10 or 20% SP to FT spermatozoa resulted in the reversal of capacitation within 30 min of its addition. In the third study, the decapacitating effects of 10% (v/v) SP addition to FT spermatozoa were examined in different media and at different incubation temperatures. It was demonstrated that the effects of SP were dependent on the temperature of the spermatozoa suspension as well as the media the spermatozoa were suspended in. The results from these three studies demonstrated that capacitation in boar spermatozoa is regulated by some constituent(s) of boar SP.