Submitted to: Avian Pathology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 7/3/2005
Publication Date: 10/20/2005
Citation: Holt, P.S., Stone, H.D., Moore, R.W., Gast, R.K. 2005. Development of a lavage procedure to collect lung secretions from chickens for evaluating respiratory humoral immunity to salmonella enteritidis. Avian Pathology. 34:396-398. 2005. Interpretive Summary: Researchers generally consider immunity in the lung to occur after infection with respiratory organisms such as influenza. Because of this, little research has been undertaken to investigate lung immunity in chickens following infection by Salmonella enteritidis (SE), an intestinal disease organism. However, lung infections by SE have been shown to occur in chickens with severe consequences for the individual birds. In mammals, it is known that immunity generated in the intestine can result in immunity at other more distant sites such as the lung. We set about to see if chickens will similarly generate an immune response in the lung following an intestinal infection with SE. To enable us to readily get a good lung sample for testing, we developed a simple technique using tubing attached to a syringe to instill a flush solution into the lung and then aspirate it. We found that a large proportion of hens intestinally infected with SE will mount a specific antibody response in the lungs against SE indicating that immunity in one location will result in immunity at other more distant locations, providing a broader, more extensive range of protection for the bird.
Technical Abstract: Following infection in chickens with Salmonella enteritidis (SE), the individual mounts an antibody response both systemically and at mucosal surfaces. The lung is not routinely thought to be a site where immunity to this organism might occur. However, colonization of the lung with Salmonella can occur and the bird may develop mechanisms to provide immune protection at this site. With this in mind we developed a simple method for performing lung lavages which allows for extracting lung secretions for antibody analysis and used this technique to test for the development of IgA anti-SE in the lungs of individuals infected in the alimentary tract with this organism. Two trials were conducted where specific-pathongen free White Leghorn hens, >60 weeks old, were orally infected with 10 million SE (trial 1) or one billion SE (trial 2) and then lung lavage samples were collected 4 or 5 weeks later in trials 1 and 2, respectively. Elevated anti-SE antibody levels in lung from infected hens was observed in significantly more infected hens compared with the non-infected control hens in both trials. These results indicate that an infection occurring at one mucosal surface will result in an antibody response at other, more distant, mucosal sites.