Immune dysfunction in rabbits associated with chronic administration of enemas and rectal insemination

NZ rabbits were treated with various combinations of enemas and intrarectal insemination (1 or 3 ml of semen a week) to investigate the effects of intestinal uptake and immunogenicity of seminal components and of an unrelated antigen, bovine serum albumin (BSA), given simultaneously. For 5 months the treatment was limited to enemas and/or semen, and total immunoglobulins and antisperm and antilymphocyte antibodies were determined. Then, without interruption of the treatments, the animals received two courses of three consecutive daily intrarectal administrations of BSA, and the humoral response was determined 7 days after each course of administration. Only 1 of 18 intrarectally inseminated animals responded with production of antisperm antibodies; none had antilymphocyte antibodies. Total immunoglobulins, however, were significantly increased in animals receiving enemas alone (p less than 0.02) or followed by insemination (p less than 0.05). The humoral response to BSA was significantly (p less than 0.01) enhanced by prior administration of enemas but was moderately reduced by simultaneous administration of semen, in a dose-related fashion.