Submitted to: American Veterinary Medical Association Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 3/24/2005
Publication Date: N/A
Technical Abstract: The pre- and post-SE-challenge mucosal immune responses within the crops of eight commercial layer-breeds (5 white-egg & 3 brown-egg layer strains) and SPF-White Leghorn chickens were evaluated. The hen groups were orally challenged with ~10e8 cfu/ml Salmonella Enteritidis PT13a. Fecal and crop samples were cultured weekly to monitor progression of SE infection. Crop SE-LPS IgA responses were determined via ELISA at weekly intervals from day 0-day 25 post-infection (pi). H&E stained tissue slides from day 34 pi crop sections were assessed for lymphoid tissue via light microscopy & assigned a semi-quantitative numerical score based upon prevalence of lymphoid aggregates & degree of cellularity. Results revealed: crop & fecal SE positive samples at day 6 pi with a decline in percentage positive at day 25 pi; a marked increase in crop SE-LPS specific IgA between day 0 (pre-challenge) to day 11 pi; and well-defined score 3-5 lymphoid tissue aggregates in day 34 pi crop sections.