PATHOLOGICAL FINDINGS IN THE INTESTINAL-TRACT AND LIVER OF CHICKS AFTER EXPOSURE TO SALMONELLA SEROTYPES TYPHIMURIUM OR KEDOUGOU

Day-old chicks were inoculated either via the feed or by direct oral i noculation with salmonellas which were either invasive or non-invasive (serotypes Typhimurium and Kedougou, respectively). Colonization of t he alimentary tract and visceral organs, determined by microbiological examination, occurred more quickly in birds inoculated orally with S. serotype Typhimurium compared with feed-challenged birds. By contrast , S. serotype Kedougou remained confined to the alimentary tract. In b irds inoculated either orally or via the feed, S. serotype Typhimurium , but not serotype Kedougou, was identified in the lamina propria of t he caecum by immunostaining. Electron microscopic examination confirme d that the organisms were within macrophages.