Iraqi Journal of Veterinary Sciences

Abstract

In this study umbilical hernias were created experimentally in eight sheep. At the 30th postoperative day, hernia developed that had the typical characteristic features of reducible hernia. The animal were divided into two groups and hernioplasty was done using freshly prepared ovine tunica vaginalis in one group and ovine pericardium in the second group. Following hernioplasty, the animals were inspected clinically. Biopsies were taken from the grafts and surrounding tissue at 15, 30, 60, and 90 days. Clinical examination of the experimental animals and the patch grafts showed no apparent abnormalities except for the occurrence of simple multifocal wound infection. Histopathological examination of the patch grafts showed inflammatory reactions that ranged from polymorphonuclear cell infiltration of the graft up to chronic foreign-body granuloma. Dense fibrous tissue was seen invading the graft particularly through perforations of the suturing needle and fissures in the graft. These histopathological changes were not seen at the 60th postoperative day except for the fibrous capsulation of remnants of suture material in the graft. No major differences were seen in the microscopic picture of hernia grafted with tunica vaginalis and those grafted with the pericardium. This study described a model for experimental induction of umbilical hernia in sheep and introduced for the first time in the literature the use of tunica vaginalis as an allograft for hernioplasty in sheep. Further studies are needed on the use of tunica vaginalis patch graft in repairing other types of tissue defects such as in duraplasty.