EFFECT OF INDUCED MOLTING ON THE SEVERITY OF INTESTINAL LESIONS CAUSED BY SALMONELLA-ENTERITIDIS INFECTION IN CHICKENS

A study was conducted to describe the intestinal lesions caused by Salmonella enteritidis infection in 20-, 40-, and 74-week-old white leghorn chickens that were undergoing a feed deprivation-induced molt. The chickens were infected on the fourth day after feed was removed. At 4 days postinfection (8 days of feed deprivation), cecal and cecal tonsil inflammation was significantly greater in molted infected chickens than in unmolted infected chickens. The cecal lamina propria and epithelium of molted infected chickens contained heterophilic infiltrates, and there were heterophils and sloughed epithelial cells in cecal lumina. Colonic inflammation, consisting of heterophils infiltrating lamina propria and epithelium, occurred more often in molted infected chickens than in unmolted infected chickens. Immunoperoxidase staining of intestinal sections from 20-and 40-week-old chickens revealed S. enteritidis antigen in the lamina propria of cecum, cecal tonsil, and occasionally the colon of molted infected chickens. The character of the S. enteritidis-induced intestinal lesions associated with molting was similar for different ages of birds.