Fertilidade de sêmen suíno avaliada pelo teste de ligação dos espermatozóides a um substrato sintético

The objective of this work was to evaluate boar semen fertility by a sperm-binding assay to a synthetic substrate. Motility (MOT) and percentage of bound sperm (PSB) were evaluated after 5, 24,48 and 72 hours of storage at 17degreesC. PSB was analyzed in solutions containing 6.25 or 12.5 million of spermatozoa/mL, with or without bovine serum albumin (BSA), processed from two to five ejaculates of four boars. Fifty eight gilts were inseminated, a single time, 24 hours after the beginning of estrus. There was a positive correlation (P = 0.0001; r = 0.33) between MOT and PSB. Higher percentages of PSB were observed with 12.5 million of spermatozoa/mL and in the presence of BSA (P<0.05). After 72 hours, boar 3 showed lower PSB (P<0.05) than the other boars. The cleavage (TC) and normal embryo rates did not differ among boars, but boar 3 showed less than 70.0% of TC belonging to the superior quartile while boars 1, 2 and 4 had more than 75.0%. After 24 hours of sperm storage, boars differ in their sperm binding to the synthetic substrate. Binding of swine spermatozoa to the synthetic substrate is higher in the presence of BSA and with the increase of spermatic concentration.