Page Banner

United States Department of Agriculture

Agricultural Research Service

Related Topics

Research Project: Intervention Strategies for Foodborne Pathogens During Poultry Production and Processing

Location: Poultry Microbiological Safety Research

2013 Annual Report


1a.Objectives (from AD-416):
1. Evaluate novel chemicals, operational protocols, and sampling methodologies used during poultry production and processing of broilers for the reduction and/or control of foodborne pathogens. Develop a model or assay that can evaluate the effectiveness of interventions on the reduction of the prevalence or pathogen load of foodborne pathogens through production and processing (effectiveness of interventions). 1.1. Assessment of novel chemical sprays, brushes, intermittent scalding / defeathering on decontamination of Salmonella and Campylobacter from floor pen challenged broilers through processing following immersion chilling. 1.2. Develop a day-of-processing challenge model for the RRC pilot processing. 1.3. Evaluate the efficacy of novel combination chemical sanitizers on the removal of Salmonella from hatching eggs and the progressive cleanliness through single stage setters/hatcher systems to the broiler growout farm.

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.


1b.Approach (from AD-416):
Campylobacter challenged broilers through processing following immersion chilling and the efficacy of novel combination chemical sanitizers on the removal of Salmonella from hatching eggs and the progressive cleanliness through single stage setters/hatcher systems to the broiler growout farm are the approaches for Objective 1.

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.


3.Progress Report:
In FY 2013, progress was made in the below stated objectives of the Agricultural Research Service’s National Program 108 Food Safety Action Plan. 4.1: Animals and their Derived Products and 1.B Systems Biology the proliferation of Salmonella.

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:.
1)Skip-a-day in trough feeders (SAD, 2 days allotted feed fed every other day);.
2)Every day in trough feeders (EDT); or.
3)Every day on the litter floor (EDL). At 5 weeks, 5 Salmonella-positive seeder pullets were commingled into each pen and ceca sampled from pen-mates at 8, 12, 16, 19, and 20 weeks. Salmonella prevalence for ceca from SAD fed pullets was significantly (P<0.05) higher at 8 weeks 70%, 12 weeks 40%, 16 weeks 10%, 19 weeks 20%, and at 20 weeks 10%. EDT fed pullets had 40% Salmonella-positive ceca at 8 weeks and only 5% at 12 weeks. EDL fed pullets had 30% Salmonella-positive ceca at 8 weeks and only 5% at 12 weeks. From neither EDT nor EDL were Salmonella detected from ceca at 16, 19, or 20 weeks. At 20 weeks pullets in each pen were orally challenged with Campylobacter and ceca sampled at 21 and 23 weeks. The SAD fed pullets had 100% and 90% positive ceca, the EDT fed pullets were 95% positive both weeks, and the EDL fed pullets were the lowest at 60% and 40% positive ceca, respectively. These results indicate that the standard pervasive commercial practice of feeding broiler breeder pullets every other day (SAD) during rearing contributes to persistently higher Salmonella and Campylobacter ceca colonization following challenge and that feeding broiler breeder pullets every-day broadcast on the litter (EDL) promotes a lower persistence of Salmonella and Campylobacter colonization after challenge during prelay rearing.


4.Accomplishments
1. Impact of feeding programs on the colonization of Salmonella and Campylobacter in broiler breeder pullets. Demonstrated that the standard pervasive commercial practice of restrictive feeding broiler breeder pullets every-other day (skip-a-day) during rearing contributes to persistently higher Salmonella and Campylobacter ceca colonization following challenge. Demonstrated that alternatively restrictive feeding broiler breeder pullets every-day by broadcasting on the litter promotes a lower persistence of both Salmonella and Campylobacter colonization following challenge during prelay rearing.

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.


Review Publications
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.

Last Modified: 10/25/2014
Footer Content Back to Top of Page