Influence of seminal plasma from rich fraction of boar ejaculated on capacitation and hyperactivation of the swine sperm stored at 17ºC for 72 hours

Abstract

The present project aims to evaluate the effect of seminal plasma from rich fraction of boar ejaculated on capacitation and sperm hyperactivation of semen stored at 17ºC for 72 hours. For this, six ejaculates of each of six mature boars will be collected by gloved-hand technique. Semen in natura will be assessed to the motility characteristics by computer-assisted sperm analysis (CASA), sperm morphology by differential interference contrast (DIC) and sperm concentration by Neubauer chamber. The ejaculate will be split into three conical 50 mL tubes, originating three treatments: non-centrifuged (NC), centrifuged followed by removal of seminal plasma after centrifugation (CS), centrifuged with suspended seminal plasma (CR). The treatments CS and CR will be subjected to centrifugation at 500xg for 10 minutes. All the treatments will be extended with Beltsville Thawing Solution (BTS) to produce an insemination dose with 30x106 spermatozoa/ml in 50 ml. Then, semen will be held for 90 minutes in the dark at room temperature before storage at 17º C for 72 hours. After this, the samples will be transferred to capacitating medium followed by incubation at 38º C with 5% CO2 and evaluated in the intervals of 0, 2 and 4 hours for the characteristics: plasma membrane fluidity (capacitation), presence of phosphorylation of tyrosine aminoacid, acrossomal integrity (acrossome reaction), hyperactivation, and plasmatic membrane and cytoplasm peroxidation. When the main effect is significant, the means will be compared by Tukey test. (AU)