|Lay Jr, Donald|
Submitted to: Journal of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: 5/23/2007
Publication Date: 6/15/2007
Citation: Moulton, K., Ryan, P., Youngblood, R., Mcgee, M., Laird, S., Harris, A., Moore, D., Kim, I., Lay Jr, D.C., Willard, S. 2007. Evaluation of Photonic Imaging in the Gastrointestinal Tract of Swine Following Oral Inoculation With Lux-Modified Salmonella typhimurium. Journal of Animal Science. 85(1):245.
Technical Abstract: The objective was to evaluate photonic emitting bacteria through different segments of the gastrointestinal tract of swine. Pigs (~ 80 kg) were inoculated orally with 3.1 or 4.1×10^10 CFU of Salmonella typhimurium transformed with plasmid pAK1-lux (S. typh-lux) for a 6 (n=6) or 12 (n=6) h incubation in vivo. Pigs were euthanized at 6 or 12 h. Intestinal regions (duodenum, jejunum, ileum, large intestine) were divided into 5 replicates of 4 segments (5 cm) each for imaging. For each replicate, two segments of each region were intact, while 2 segments were opened to expose the digesta. Sub-samples of digesta were analyzed for CFU, and images were analyzed for relative light units/sec (RLU/sec). At 6 h, a higher (P<0.05) concentration of emitting bacteria, and consequently higher (P<0.05) detection of photonic emissions was observed in small intestine than large intestine. The correlations (6 h) of photonic emissions in opened segments to bacterial concentrations were r = 0.73, 0.62, 0.56, and 0.52 (P<0.05) in duodenum, jejunum, ileum, and large intestine, respectively. Photonic emissions were higher (P<0.05) in jejunum, ileum, and large intestine than in duodenum of intact segments post 6 h incubation. At 12 h, a higher (P<0.05) concentration of emitting bacteria in jejunum and ileum of open segments was observed than in duodenum and large intestine of open segments. Photonic emissions were higher in ileum than duodenum, jejunum and large intestine of open segments (P<0.05). The correlations (12 h) of photonic emissions in opened segments to bacterial CFU’s were r = 0.71 and 0.62 for jejunum and ileum, respectively (P<0.05). At 12 h, a higher (P<0.05) concentration of emitting bacteria in jejunum and ileum of intact segments was observed than in duodenum and large intestine. These data indicate CFU were higher in small intestine after 6 and 12 h incubations, and a minimum of 2.0×105 CFU yields detection through these tissues (~ 1.0 to 21.0 RLU/sec). This study demonstrates feasibility of using biophotonics in research models for evaluating pathogenicity of Salmonella in swine.