Experimental induction of renal lesions in chickens.

The present work was conducted to investigate the possibility of inducing renal lesions in chickens subcutaneously or orally inoculated with E. coli [E. coli O1K67(B12)], Staphylococcus aureus and Actinomyces pyogenes. The strains were previously isolated from the kidneys of broilers showing different pathological lesions. The gross lesions observed in the kidneys included enlargement, congestion, haemorrhagic spots in addition to dilatation and distension of the ureters. The microscopic lesions were mainly interstitial nephritis. The lesions were acute and changed gradually to subacute or chronic nephritis. The glomerular lesions were not common. The wall of the primary branches of the ureter and the ureters was heavily infiltrated with inflammatory cells, also granular and albuminous casts were seen in the renal tubules. The lesions were not related to the inoculated pathogen, although they were more severe in chickens inoculated with E. coli and Staph. aureus more than in Actinomyces pyogenes. Reisolation of the inoculated pathogens was more successful from the birds inoculated subcutaneously than from those infected orally.