Effects of seminal plasma on motility characteristics and fertility of cryopreserved boar sperm

Abstract

This project aims to verify the modifications generated by the technique of cryopreservation on motility characteristics, and determine if addition/maintenance of boar seminal plasma before or after thawing reduces these effects and improves fertility. For this, ejaculates from six boars will be collected. After analyses, the semen in natura, will be diluted before centrifugation. After this, semen pellet will be divided in two treatments: Control (CON) - suspended with extender for cryopreservation and (PAC) - suspended with extender for cryopreservation within 10 % (v/v) of seminal plasma. Extended semen will be loaded in 0.5 mL straws and then subjected to cryopreservation. Ten straws from each batch will be thawed from group PAC and CON. Forty five mL of Prolimax® extender will be added to CON and PAC groups in order to obtain fifty mL of insemination dose within 60x106sptz/mL. Another ten straws from CON will be thawed and extended with Prolimax®, within 10 % (v/v) of seminal plasma giving rise to the third treatment, group PDC. After addition of treatment the samples remain in the water bath at 37° C until the end of analysis evaluated in periods 0 and 120 minutes. The semen analysis will consist in the computerized analysis of the characteristics of motility (CASA). Fertility test will be performed in seventy five gilts. Inseminations will be performed with three treatments CON (n=25), PAC (n=25) e PDC (n=25). Continuous variables are compared by Tukey test and the fertility and birth rate will be analyzed by Chi-Square non-parametric test, both for P<0.05.