Location: Poultry Microbiological Safety Research
Title: Aerobic and anaerobic cecal bacterial flora of commercially processed broilers Authors
Submitted to: International Poultry Scientific Forum
Publication Type: Abstract Only
Publication Acceptance Date: November 7, 2011
Publication Date: January 23, 2011
Citation: Hinton Jr, A., Ingram, K.D., Jenkins, M.B. 2011. Aerobic and anaerobic cecal bacterial flora of commercially processed broilers. International Poultry Scientific Forum. Technical Abstract: Differences in the bacterial flora of aerobic and anaerobic cultures of broiler ceca collected from a commercial poultry processing facility were determined. Bacterial isolates from cecal cultures were selected based on the ability of the bacteria to grow in media supplemented with lactate and succinate. Primary cecal cultures were grown by adding approximately, 1 g of cecal contents to 100 ml of media composed of (g/l) tryptose, 10.0; yeast extract, 5.0; sodium chloride, 5.0; beef extract, 2.4; glucose, 2.0; and cysteine, 0.5. Media was adjusted to pH 7.0 and sterilized by autoclaving at 121C for 15 min. The inoculated media was incubated aerobically or anaerobically at 35C for 48 h. One ml aliquots of the incubated cultures were transferred to 10 ml of modified growth media containing no glucose and supplemented with 0, 50, 100, or 150 mM of succinate and lactate. Cultures in modified media were incubated at 35C for 48 h under the same atmosphere as primary cecal cultures. Two additional transfers of incubated cultures into fresh media were made using 10µl bacteriological loops. Final cultures were plated on agar media prepared by adding 1.5% agar to the corresponding lactate-succinate broth media. Inoculated plates were incubated under appropriate atmospheric conditions at 35C for 48 h. Isolated colonies were then selected from agar and identified using the Biolog Bacterial Identification System. Results indicated that Proteus mirabilis and Enterococcus spp. were the predominant bacterial isolates recovered from all media incubated aerobically. Predominant bacterial isolates recovered from media incubated anaerobically included Arcanobacterium pyogenes, Bacteroides spp., Clostridium spp., Lactococcus lactis, and P. mirabilis from media supplemented with 0, 50, or 100 mM lactate and succinate; and A. pyogenes and Veillonella spp. from media supplemented with 150 mM lactate and succinate. Findings illustrate that incubation atmosphere and metabolites added to media may influence the final bacterial flora of cultures from cecal contents. Findings also demonstrate that cecal contents of broilers entering processing facilities may contain bacteria that have been shown to play important roles in the production of some substances that can inhibit the growth of foodborne pathogens.