Experimental reconstruction of teat mucosa by vestibular mucosal graft in cows. A histopathologic and radiographic study

Injuries to the teat in dairy cows can result in partial or complete obstruction of the teat lumen. Different treatment techniques have been used to restore normal function in injured teats, one of which is autogenous mucosal grafts. The purpose of this study was to evaluate the vestibular mucosa as a replacement for teat mucosa in severe teat injuries. Sixteen teats of four healthy, mature, non-gravid Jersey cows were randomly divided into two equal groups. Under high epidural analgesia and after surgical preparation a 1 x 1.5 cm piece of teat mucosa was removed. In group 1, the defect was replaced by a 2 x 2.5 cm vestibular mucosa, whereas in group 2, the defect was left open. In both groups, a sterile disposable teat cannula was inserted into the teat cistern following surgery. To evaluate luminal diameter, double contrast radiography with constant air pressure was performed every 25 days till day 125, after which the animals were slaughtered and teats removed for histopathological study (H&E staining). On the basis of radiographic examination, luminal narrowing in group 2 was significantly more severe than in group 1. Histopathologically, the entire mucosal grafts of group 1 were taken and a good adhesion could be seen between the graft and the host epithelium. In group 2, severe submucosal fibrosis and mucosal papilloid hyperplasia resulted in severe narrowing of the teat cistern. According to the results of this study, it can be concluded that using vestibular mucosal grafts with temporary insertion of teat cannula can be considered as a method of treating teat mucosal injuries.