Effects of bovine antisperm antibodies on fertilizing capacity of bovine spermatozoa

소 항정자항체가 소 정자의 수태능력에 미치는 영향

This study was directed at inducing the production of antibodies by immunizing heifers with bovine sperm antigen and on measuring the serum antibodies using indirect immunofluorescence assay(IFA) and agglutination test. The effect of antisperm antibodies on fertilizing capacity of bovine spermatozoa was evaluated. 1. Three heifers between 12- and 15- month old were immunized with bovine spermatozoa or phosphate-buffered saline. In heifers immunized with bovine spermatozoa serum IgG level was highest between 3 weeks and 5 weeks postimmunization detected by IFA. The antibody levels persisted through week 7 and slowly declined until week 20 and then antisperm antibodies were localized on spermatozoa. The fluorescent antisperm antibodies were detected at 2~20 weeks and at 6~9 weeks postinoculation on acrosome and tail, respectively. Among 21 sera from repeat breeder cows, only one cow has shown positive antisperm antibody response detected by IFA. 2. In spite of vital rate of bovine sperm after swim-up was not significantly affected by different concentration of antisperm antibodies in sera, the numbers of bovine sperm after swim-up were significantly reduced in proportion to the increased concentration of antibodies. Above 1/512 dilution of antibody neither influence on vital rate and numbers of bovine sperm nor sperm agglutination after swim-up. The study has also shown that the vital rate and number of sperm after swim-up and capacitation were also significantly reduced by the addition of antisperm antibodies. Although antisperm antibodies did not influence on the acrosome reaction rate of sperm during swim-up, did significantly reduce the sperm acrosome reaction rate after capacitation. The studies have resulted that the bovine antisperm antibodies can prevent the sperm motility by agglutination and block the capacitation and acrosome reaction of bovine sperm.