Histopathological findings of foot-rot disease which causes deaths in a sheep flock

ABSTRACT

Background: Foot-rot is a contagious bacterial infection of the feet of sheep that causes lameness. This infection leads to major economic losses in wool, meat, and dairy industries throughout the world. Pathogenesis of foot-rot can be described as the damage of the interdigital skin, invasion of fecal bacterium Fusobacterium necrophorum, and finally the involvement of Dichelobacter nodosus in the infection. In the worst cases, the disease becomes widespread, and systemic bacterial infections may occur. The present study aims to describe macroscopic and histopathological findings of foot-rot lesions formed in the foot, heart, liver, and lungs to draw attention to these aspects of the disease.Case The material of the study consisted of a 3-year-old sheep. The investigation was composed of the disease history; post-mortem examination; and histopathological analysis of lung, liver, heart, and foot lesions. At the anamnesis, it was reported that the diseased animal had lameness and weakness with other clinical symptoms, and approximately 10 infected sheep had died within a 1-week period. At necropsy, malodorous ulcerative lesions between the nails; focal-disseminated foci in the liver, lung, and heart; yellowish matte thickening in the heart valves; and hydropericardium were detected. After necropsy, tissue samples taken from the skin, lungs, spleen, kidneys, and liver were fixed in a 10% buffered formalin solution, paraffin embedded, sectioned, and stained with hematoxylin and eosin. Giemsa staining was done to detect the agents in the tissues. The slides were examined and photographed using a light microscope. Histopathological examination revealed that ulcerations between the nails were lesions shaped as the result of the foot rot disease...(AU)