|Nannapaneni, R - UNIV OF ARKANSAS|
|Johnson, M - UNIV OF ARKANSAS|
Submitted to: Southern Poultry Science Society Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: October 8, 2002
Publication Date: July 25, 2003
Citation: HUFF, G.R., HUFF, W.E., BALOG, J.M., RATH, N.C., NANNAPANENI, R., JOHNSON, M. RESPIRATORY CHALLENGE OF DAY-OLD TURKEY POULTS WITH LISTERIA MONOCYTOGENES SCOTT A RESULTS IN SYSTEMIC INFECTION WITH HIGH MORTALITY AND ORGAN AND KNEE SYNOVIAL TISSUE INVASION. SOUTHERN POULTRY SCIENCE SOCIETY MEETING. 2003. V. 13(SUPPL.1): ABSTRACT P. 19. Technical Abstract: Turkey osteomyelitis complex (TOC) is a stress related chronic disease of processing age turkeys in which opportunistic bacteria colonize the soft tissue, joints, and bone of otherwise healthy-appearing carcasses. We have hypothesized that turkey products and processing plants may become contaminated with opportunistic pathogens, including Listeria monocytogenes (Lm), contained in these lesions. The pathogenesis of the Scott A (serotype 4b) strain of Lm was studied by challenging day-of-age male turkey poults by air sac inoculation with tryptose phosphate broth containing 10e0 cfu (Control), 10e4, 10e5, or 10e6 cfu (Low challenge) or 10e7 or 10e8 cfu (High challenge) of Lm Scott A. Most mortalities occurred between 2 and 4 days post-infection. At 4 days post infection, six non-challenged control birds were necropsied and cultured for Lm. Mortality at 2 weeks PI ranged from 25-100% and was directly correlated with level of challenge (P =0.0001). Listeria challenge resulted in significantly decreased relative weight of the bursa of Fabricius and increased relative weight of the spleen, resulting in a highly significant effect on the bursa to spleen ratio (P = 0.0001). Lm was isolated from challenged birds but not from controls by direct plating of liver (P = 0.0001), pericardium (P = 0.0001), brain (P = 0.0002), and both left (P = 0.01) and right (P = 0.001) knee synovium cultures plated directly from transfer swabs onto UVM Listeria selective agar. Isolates were confirmed as Lm using Gram stain and biochemical charcterization (API i>Listeria and the Biolog system). High challenge resulted in confirmed Lm isolation from 48% of left knee and 59% of right knee cultures. Low challenge resulted in isolation of Lm from 11% of both left knee and right knee cultures. Left knee synovial tissue swabs that were negative on direct plating were pre-enriched in Fraser broth and replated on UVM Listeria selective agar yielding an additional 16% confirmed Lm isolation. These results suggest that Lm Scott A colonization of synovial tissue can initiate in day of age poults and that respiratory tract infection with Lm Scott A is both invasive and pathogenic in day-old turkey poults.