Iranian Journal of Veterinary Research, University of Shiraz, Vol. 7, No. 1, Ser. No. 14, 2006 59 Short Paper Abattoir survey of bovine pyelonephritis Karimi, I. 1* ; Shahgholian, M. 2 ; Ebrahimi, A. 1 and Mahzounieh, M. R. 1 1 Department of Pathobiology, School of Veterinary Medicine, University of Shahrekord, Shahrekord, Iran; 2 Graduated from School of Veterinary Medicine, University of Shahrekord, Shahrekord, Iran * Correspondence: I. Karimi, Department of Pathobiology, School of Veterinary Medicine, University of Shahrekord, Shahrekord, Iran. E-mail: irkarimi@yahoo.com Summary In order to investigate the prevalence and detection of etiological agents of pyelonephritis in Shahrekord abattoir, 404 kidneys of slaughtered cattle (207 female and 197 male) were inspected. Kidney samples, which had gross changes were obtained for histological examination. Urine and renal tissue samples were also collected aseptically for microbiological examination. In histological examination pyelonephritis were observed in 3 cases (0.74%), one of which occurred in a 7-year-old cow and the others in bulls less than 2- year-old. In microbiological examination E. coli was isolated from urine and renal tissues in 2 cases and Staphylococcus aureus isolated only from renal tissue in the other case. Key words: Pyelonephritis, Cattle, Abattoir Introduction Pyelonephritis is a specific infection of the urinary tract of cattle, caused by some bacteria, particularly Corynebacterium renale, characterized by chronic purulent inflammation in the bladder, ureters and kidneys (Radostits et al., 2000). E. coli, Proteus sp., Klebsiella sp., Staphylococcus sp., Streptococcus sp. and Pseudomonas aeruginosa are also common causes of lower urinary tract infection and pyelonephritis in all species (McGavin et al., 2001). Pyelonephritis may exist without clinical signs of disease. Frequently the acute infection is undiagnosed, resulting in chronic infection characterized by vague signs of weight loss, anorexia and decrease in milk production in affected cattle (Rehbun et al., 1989). The aim of this study was to investigate the prevalence of pyelonephritis and detection of bacterial agents of pyelonephritis in slaughtered cattle in Shahrekord abattoir. Materials and Methods In this study, which was carried out through winter (2001) to spring (2002), the kidneys of 404 slaughtered cattle (207 female and 197 male) were inspected. The number, age and gender of animals were recorded. Kidney tissue samples, which had gross changes were obtained from 87 cattle and placed in 10% formalin buffered for histological examination. Urine samples from the bladder and renal tissues were also collected aseptically for microbiological examination. Urine samples centrifuged at 1500 rpm for ten min then sediments streaked on sheep blood agar and incubated for 24-72 hrs at 37ºC. Tissue samples were extracted aseptically and cultured as urine samples. Suspected colonies of common agents of pyelonephritis followed by microscopic examinations and appropriate biochemical tests (Quinn et al., 2002). For histological examination fixed tissue samples were embedded in paraffin wax, sectioned in 5 microns and stained with Haematoxylin and Eosin. Results In histological examination pyelone- phritis was observed in 3 cases, one in a 7- year-old cow and two in bulls less than 2- year-old. The lesions included a marked