Submitted to: American Association of Avian Pathologists
Publication Type: Abstract only
Publication Acceptance Date: 3/1/2007
Publication Date: 7/14/2007
Citation: Holt, P.S., Vaughn, L., Moore, R.W., Gast, R.K. 2007. Crop Isolated Lymphoid Follicles and Ileal Peyer’s patches in Egg-Layer Hens Challenged with Salmonella enterica Enteritidis. American Association of Avian Pathologists. Interpretive Summary:
Technical Abstract: The enteric pathogen Salmonella enterica Enteritidis (SE) can be harbored within the upper and lower gastrointestinal (GI) tract of chickens. Induction of immune response by SE at various alimentary tract regions may perhaps be attributable to local gut-associated lymphoid tissue (GALT). The study investigated the mucosal immune response and GALT within crop and ileum of specific-pathogen-free White Leghorn (WL) hens and four commercial layer-hen breed-strains following per os SE challenge. Crop contents and feces were cultured weekly to monitor SE infection. Crop lavage and lower GI tract gut-flush samples were analyzed for SE lipopolysaccharide (LPS)-specific IgA humoral response by enzyme-linked immunosorbent assay. Gross and microscopic evaluation of crop and ileum determined presence/absence of lymphoid tissue/GALT. Morphometric analysis of lymphoid tissue sites was conducted. Results showed elevated SE-LPS-specific IgA response in crop lavage and gut-flush samples. Well-defined isolated lymphoid follicles were observed in hematoxylin & eosin stained tissue sections from mid-body region of crop. Peyer’s patches of proximal and distal ileum were identified at two consistent locations in eosin-Y and modified-crystal violet stained fresh tissue segments. Finding crop isolated lymphoid follicles and ileal Peyer’s patches in SPF WL hens and commercial layer-hen breed-strains appears to support the idea that crop and ileum of the chicken have the capacity to generate a local mucosal immune response against SE.