Alteration of the Spermatozoal Glycocalyx and its Effect on Duration of Fertility in the Fowl (Gallus Domesticus)1

Abstract

The hypothesis that sialic acid has a role in spermatozoal sequestration within the hen''s oviduct was tested by treating spermatozoa with Clostridium perfringens neuraminidase. Spermatozoal content of sialic acid ranged from 94 to 135 .mu.g per 109 spermatozoa (n = 12 roosters). Spermatozoa contained 80% of total seminal sialic acid (coefficient of variation = 4.6%). Spermatozoal sialic acid content was reduced by 18% when 109 spermatozoa were incubated at pH 6.5 with 10IU neuraminidase activity (Tyoe V, Sigma Chemical Co.). Such treatment had no effect on spermatozoal viability as evidence by ethidium bromide uptake. However, treatment of spermatozoa with neuraminidase prior to intravaginal insemination reduced fertility by 24 percentage units (p < 0.001). In contrast, when similarly treated spermatozoa were deposited in the magnum via laparatomy, fertility was not affected (p > 0.05). The preceding work was done eith neuraminidase prepared by salt fractionation (Type V, Sigma, Chemical Co. ). Type V neuraminidase was absorbed ot diethylaminoethyl-Sephacel and then eluted with a stepwise KCl gradient. Treatment of spermatozoa with this preparation of neuraminidase (10 IU/109 spermatozoa) prior to intravaginal insemination reduced fertility by 19 percentage units (p < 0.001). Decreased fertility could not be attributed to contamination of neuraminidase preparations with proteolytic activity. We conclude that spermatozoal sialic acid has a role in spermatozoal sequestration within the hen''s utero-vaginal glands.