Microbiologia Médica e Diagnóstico

Histopathological and Bacteriological Study on Hepatic Abscesses of Herrik Sheep

Abstract

Aliasghar Tehrani, Javad Javanbakht, Mehdi Agha Mohammad Hassan, Mohammad Zamani, Mojtaba Rajabian, Hamid Akbari and Radmer Shafei

 Background: Liver abscesses constitute a major economic problem and there exists very less information in association with liver abscesses in ovine. Although studies in several countries have reported on the incidence of ovine hepatic abscesses at abattoirs, few surveys have identified the etiology and pathological characteristics of these abscesses.
Aim: The aim of this research is histopathological and bacteriological study on hepatic abscesses of Herrik sheep.
Methods: The lesion specimens of 5000 condemned sheep livers were collected from four provinces (Western Azerbaijan, Eastern Azerbaijan, Kordestan and Kermanshah) abattoirs for bacteriological (aerobic and anaerobic) culture and pathologic examination.
Results: Grossly, 230 liver abscesses (4.6%) found that 110 cases were in female sheep (47.8%) and 120 cases were in male sheep (52.1%). Most of the abscesses were found in diaphragmatic surface (23.48%), visceral surface (22.1%) and right lobes (21.3%) of the livers. Regarding the presence of abscesses, there was no significant difference between sexes, lobes and surfaces of livers (p>0.05). The following bacteria were isolated: from 120 of which, Corynebacterium (52.4%) was isolated, and from 26 of which, Pasteurella (11.3%), from 25 of which, Escherichia coli (11.1%), from 16 of which, Proteus (7.2%), from 16 of which, Pseudomonas aeruginosa (7.2%), from 13 of which, streptococcus (5.5%), from 12 of which, staphylococcus (5.3%) were isolated and no bacteria were isolated from the remaining 2 liver abscesses.
Conclusions: Our study suggested that Corynebacterium pseudotuberculosis is the most prevalent bacterium incriminated for hepatic abscesses in sheep. Histologically, these lesions had a core of caseous necrosis, encircled by a zone of necrotic phagocytic cells and bacteria with cellular characteristics of Corynebacterium pseudotuberculosis and a connective tissue capsule with calcification