An immunopathologic study of the bovine prepuce.

The prepuces of 83 bulls with macroscopically normal reproductive tracts were obtained at slaughter and microbiological, immunological, and histologic studies were done and the findings were correlated. Some bulls had been vaccinated on several occasions against Campylobacter fetus. Mean concentrations of intrapreputial immunoglobulins (Ig) in 27 bulls were IgG1 - 1.8 +/- 5.2; IgA - 0.16 +/- 0.15; and IgM - 0.24 +/- 0.24 mg/ml. High concentrations of IgG2 in some bulls precluded precise estimation but mean concentration was in excess of 11.0 mg/ml (range 0 to 20+ mg/ml). Differences between these concentrations were significant (P less than 0.005). Mean prevalences of class specific, immunoperoxidase-labeled plasma cells in the preputial dermis of 35 bulls were IgG - 39.0 +/- 9.3; IgA - 16.6 +/- 6.6; and IgM - 2.2 +/- 1.8 labeled cells/100 nuclei (P less than 0.001). The prevalence of IgG labeled cells in the preputial dermis was, however, negatively correlated with the concentration of intrapreputial IgG (IgG1 + IgG2) (r = -0.4; P less than 0.05). Except for an apparently lower intrapreputial Ig concentration in Trichomonas foetus-infected bulls than in negative ones, there were no significant correlations between intrapreputial immunoglobulin concentration, histologic findings, and age, infection, or vaccination status of the bulls.