MORPHOLOGIC CHANGES AND IMMUNOHISTOCHEMICAL DETECTION OF VIRAL-ANTIGEN IN OVARIES FROM CATTLE PERSISTENTLY INFECTED WITH BOVINE VIRAL DIARRHEA VIRUS

Objective-To identify morphologic differences in ovaries from cows per sistently infected with bovine viral diarrhea virus (BVDV) and determi ne ovarian cell types infected in these cows. Design-A comparative stu dy of ovaries in cattle persistently infected with BVDV and cattle not persistently infected with BVDV, using morphologic and immunohistoche mical analysis. Animals-6 postpubertal cows persistently infected with BVDV and 6 postpubertal cows not persistently infected with BVDV. Pro cedure-Ovaries were compared morphologically by counting the number of normal structures present on 3 histologic sections taken from each ov ary. Immunohistochemistry was accomplished, using an indirect, monoclo nal antibody-linked. avidin-biotin-peroxidase complex procedure. Resul ts-Significant (P < 0.01) decrease in the number of tertiary follicles , graafian follicles, atretic follicles, and corpus hemorrhagicum/lute um/albicans was observed in cows persistently infected with BVDV. No d ifference in numbers of primordial or secondary follicles was observed . Immunostaining of BVDV antigen in luteal cells and macrophage-like c ells was evident in ovaries from cows persistently infected with BVDV. Conclusions-Cows persistently infected with BVDV appear to have signi ficant morphologic changes in their ovaries that suggest reduction in normal ovarian activities. Furthermore, BVDV antigen can be identified in specific ovarian cell types in cattle persistently infected with B VDV. Clinical Relevance-The changes observed may reduce reproductive p erformance in cows persistently infected with BVDV, and may be of impo rtance when trying to salvage valuable genetic material from persisten tly infected cows through embryo transfer. it is yet to be determined whether similar findings are true in cows acutely infected with BVDV.