Location: Poultry Microbiological Safety Research
2013 Annual Report
2. Identify and evaluate specific risk factors in the production and management, transport, or processing environments that are correlated with bird/egg contamination of foodborne pathogens. Evaluate how these risk factors affect the movement and persistence of foodborne pathogens in poultry and poultry products and develop potential intervention and control strategies. 2.1. Evaluate feeding programs for broilers during brooding and rearing that promote resistance to Salmonella and Campylobacter colonization and diminish flock persistence of these pathogens at slaughter age. 2.2. Evaluate pullet feed restriction and distribution programs that promote resistance to Salmonella and Campylobacter colonization and diminish persistence with the onset of lay.
Evaluation of feeding programs for broilers during brooding and rearing that promote resistance to Salmonella and Campylobacter colonization and diminish flock persistence of these pathogens at slaughter age and pullet feed restriction and distribution programs that promote resistance to Salmonella and Campylobacter colonization and diminish persistence with the onset of lay are the approaches for Objective 2.
Impact of feeding programs on the colonization of Salmonella and Campylobacter in broiler breeder pullets.
Broiler breeder chicks were placed in an experimental pullet rearing facility and divided into 3 groups (270 pullets each) and fed one of the following programs:.
2. Inoculation routes for Campylobacter colonization in broiler chicks. A marker strain of Campylobacter (C. coli gentamicin resistant) was introduced at levels ranging from 15 to 2,000 cells into assorted body openings (mouth, eye, cloaca, or nasal) of one day old broiler chicks. Five to seven days later, the ceca were analyzed and the Campylobacter levels were determined. All four routes resulted in levels in the ceca of approximately 10 million/gram, thereby producing potential seeder birds for the flock. This study strongly suggests that potential Campylobacter seeder birds can develop from contamination entering an assortment of body openings in the newly hatched chick emphasizing the need to control Campylobacter in breeder flocks, hatcheries, and broiler houses.
3. Inability of presently used laboratory methods to isolate Salmonella from poultry and animal feeds. After overnight incubation in commonly used preenrichment media, mixed feeds and feed ingredients can reach a low pH of 3.8 to 5.0 that may kill or injure Salmonella in the first step of the analysis. The percentage death and injury for four different Salmonella serovars were determined at these low pHs. At pH 4 after 6 and 24 hour exposure, the percentage of death for S. Heidelberg 90.7 and 99.9%, S. Kentucky 98.2 and 100%, S. Typhimurium 99.9 and 99.9%, and S. Enteritidis 92.3 and 99.9%, respectively. An expert international consensus on the most appropriate sampling method for determining the Salmonella status of poultry feed has never been reached. There are inherent weaknesses in many frequently used methods. One of these is the acid injury and death of Salmonella in the first step of the process thereby producing many false negative analyses in the examination of commercial feed. Laboratories worldwide are presently unaware of this acidic nature of the preenrichment step leading to death and injury of naturally occurring Salmonella.
Cox Jr, N.A., Richardson, L.J., Maurer, J.J., Berrang, M.E., Cray, P.J., Buhr, R.J., Byrd Ii, J.A., Lee, M.D., Hofacre, C.L., O'Kane, P.M., Lammerding, A.M., Clark, A.G., Thayer, S.G., Doyle, M.P. 2012. The evidence for horizontal and vertical transmission in Campylobacter passage from hen to her progeny. Journal of Food Protection. 75(10):1896-1902.
Buhr, R.J., Spickler, J.L., Ritter, A.R., Bourassa, D.V., Cox Jr, N.A., Richardson, L.J., Wilson, J.L. 2013. Efficacy of combination chemicals as sanitizers of Salmonella-inoculated broiler hatching eggshells. Journal of Applied Poultry Research. 22(1):27-35.
Cox Jr, N.A., Cason, J.A., Buhr, R.J., Richardson, K.E., Richardson, L.J., Rigsby, L.L., Cray, P.J. 2013. Variations in preenrichment pH of poultry feed and feed ingredients after incubation periods up to 48 hours. Journal of Applied Poultry Research. 22(2):190-195.