Evaluation of the possible immunological function of the chicken crop (ingluvies)
Vaughn, Lara Elizabeth
MetadataShow full item record
The crop (ingluvies) of the chicken (Gallus gallus) is an anatomical diverticulum of the esophagus and is regarded as a food storage organ. Additionally, the crop may function as a component of the extensive mucosal immune system of the gastrointestinal tract. Following experimental per os (oral) challenge with Salmonella enterica serovar Enteritidis (SE), a SE-lipopolysaccharide (LPS)-specific IgA humoral immune response was detected within the crop and a recall response to SE antigen was generated after SE re-infection. Increased lymphoid tissue was observed within the crop lamina propria of SE-infected chickens compared to uninfected controls. B-lymphocytes and plasma cells were identified within isolated lymphoid follicles (ILF), thus cellular populations exist that have the capacity to generate a humoral response locally within the crop. Commercial egg-layer hen strains and specific pathogen free (SPF) White Leghorn (WL) chickens presented similar findings of an increased SE-LPS-specific IgA response and lymphoid tissue presence within the crop organ post-SE infection. Bacteriological assessment of crop lavage samples revealed viable SE harbored within the crop and that SE persisted within the organ for extended time. The crop may be a potential reservoir for spread of SE in flock and/or a potential source of SE contamination to poultry carcasses during processing. The chicken crop deserves more attention as part of the integrated mucosal immune system and as an organ of importance in SE pathogenesis.