FREEZING OF MAIDEN STALLION SEMEN - MOTILITY AND MORPHOLOGICAL FINDINGS IN SPERM CELLS ASSESSED BY VARIOUS STAINING METHODS INCLUDING A MONOCLONAL-ANTIBODY WITH REACTIVITY AGAINST AN ANTIGEN IN THE ACROSOMAL GROUND SUBSTANCE

From a group of thirteen 3-year-old Hanoveranian maiden stallions ejaculates were collected on 5 consecutive days and frozen each in 3 different packaging forms. Fresh, resuspended and frozen/thawed semen was tested for motility and morphology with special regard to acrosomal integrity. Concerning packaging form no differences were found between 4 ml maxi straw, flattened 1.7 ml straw and 0.5 ml straw. The comparison of 3 different conventional staining techniques with an immunofluorescence test, employing a monoclonal antibody against an antigen in the acrosomal ground substance, revealed that staining sperm cells with the antibody yielded far more reproducible and consistent results - especially in diluted semen - than staining with Karras, modified Karras or Spermac(R).