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The purpose of this study is to determine the impact of wild bird population movement and related environmental factors on the prevalence of Salmonella and Campylobacter on grazing animals of farmlands through fecal contamination. We will address the study's purpose by comparing the prevalence of Salmonella and Camplyobacter spp. in farm situations that attract wild birds to the prevalence of Salmonella and Camplyobacter spp. in farm situations that removes wild bird attractants. Data from this study will be utilized to provide a scientific basis for mitigating the risks of food contamination by wild birds.
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Objective 1: To investigate the impact of bird populations on the prevalence of Salmonella and Campylobacter spp. in grazing animals (sheep and goats) and their feeding environment within and outside of bird migratory seasons. <P>Objective 2: To evaluate the effectiveness of a preventive approach that removes wild bird attractants (water and feed sources) on wild-bird populations and the prevalence of Salmonella and Campylobacter spp. in grazing animals and their feeding environment.
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Once accomplished, Objective 1 will enable scientists, for the first time, to directly link the populations of wild birds to farm contamination under normal conditions. Data generated from this risk assessment is particularly important for regions (including VA and MD) with dense migratory bird activities. Objective 2, on the other hand, will test an approach that could potentially control bird congregation and pathogen contamination on farmland. Data on the effectiveness of the control approach could be used to improve agricultural practices.
NON-TECHNICAL SUMMARY: The purpose of this study is to determine the impact of wild bird population movement and related environmental factors on the prevalence of Salmonella and Campylobacter on grazing animals of farmlands through fecal contamination. Data from this study will be utilized to provide a scientific basis for mitigating the risks of food contamination by wild birds.
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APPROACH: a. Farm management: A total of 16 one-acre pastures will be fenced to each host 12 weaned lambs and kids (mixed sex; known to be free of Salmonella and Campylobater by detection and not treated with Salmonella and Campylobacter antibiotics). For Objective 1, each site will be equipped with a set of open water tubs and feed pans that are routinely refilled with clean water and grains to feed animals and attract wild birds. This represents a standard small farm operation that allows uncontrolled interaction between wild birds and farm animals. Each year, the month of May-June and October-November will be selected to conduct experiments to represent non-migratory and migratory seasons of wild-birds, respectively. Each season, the experiment (with animals on experimental pastures) will last for 6 weeks. Objective 1 will be conducted twice a year over two years at both VSU and UMES. For Objective 2, each site will be managed similar to Objective 1; however, animals will be feed mainly by grazing (no open-field supplement will be given) and water will be supplied using nipple-waterers. This represents a modified small farm operation that prevents high frequency of interactions between wild birds and farm animals. The experimental protocol for Objective 2 and Objective 1 will be conducted side-by-side at both VSU and UMES. b. Bird observation: Investigators will capture and release a total of 120 wild birds per season from sites fitted with food attractants at the week prior and the week after each experimental trial from VSU and UMSE study locations. Each bird will be identified and have cloacal samples collected for microbiological tests to establish pathogen levels in wild bird populations at the sites. Data on bird activities will be collected from targeted surveys and digital video recording. Surveys will be conducted by trained observers who will record and map all birds seen within each study replicate during 12 timed bouts per week. c. Microbiological sampling and testing: A total of 3,072 fecal samples from the farm animals will be collected for pathogen testing. At the same time, 1 water sample and 1 environmental swab of the feeding pan will be collected for evaluating feeding environment pathogen transmission site; this will add 512 samples for testing. For birds, an environmental swab will be used to swab each trapped bird around the cloaca; this will add another 480 samples. The total number of microbial samples is 4064. Each sample will be analyzed for the presence or absence of Salmonella and Campylobacter. Positive controls will be included in the protocol. Standard protocols will be used for molecular sub-typing of Salmonella enterica and Campylobacter jejuni using Pulsed-field Gel Electrophoresis.
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PROGRESS: 2006/09 TO 2009/08<BR>
OUTPUTS: Wild-birds are potential sources of enteric disease infections in farm animals. This study was designed to evaluate the potential pathways and control of foodborne pathogen transmission between wild-birds and farm animals. At two farms, a total of 14 one-acre pastures were fenced to each host 12 sheep and goats. For the control group, pastures were set-up with open water tubs and grain pans to feed animals and attract wild birds. In contrast, the treatment group used nipple-waterers and custom feed pans. Fecal and water samples were taken every two weeks in May-June and October-November for two years. The samples were analyzed for the presence of Salmonella and Campylobacter using selective plating, immunoassays, and/or biochemical confirmation techniques. From small ruminants and captured wild birds, respectively, 2379 and 393 fecal samples were collected for pathogen detection. Campylobacter spp. were found in 6.5 and 8.7 percent of the fecal samples from small ruminants and wild birds respectively. C. jejuni was isolated from 87 and 91 percent of corresponding positive samples. Salmonella spp. were only found in 1.1 percent of feces from small ruminants and 0.3 percent of wild birds. Although wild birds were more attracted to the feeding areas in pastures with open water tubs and grain pans, there was no significant difference in pathogen prevalence between control and treatment animal groups. Furthermore, pathogens were not found in any water samples. Additional analysis is ongoing to evaluate the potential links between pathogens isolated in this study using pulsed-field gel electrophoresis. <BR> PARTICIPANTS: One graduate student from University of Maryland-Eastern Shore was involved in this study. She has generated a research abstract and presentation for future scientific meetings. <BR> <BR>
IMPACT: 2006/09 TO 2009/08<BR>
Previously, wildlife has been considered as a source of on-farm contamination; however, no report has directly assessed the impact of wild birds on foodborne pathogen transmission or methods for managing this risk. The lack of strategies to avoid contacts between migratory birds and farm animals further compounds the fear of bird-transmitted human diseases. We anticipate this project will generate knowledge of bird control and pathogen transmission with applicability for improving agricultural practices.
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PROGRESS: 2006/09/01 TO 2007/08/31<BR>
The purpose of this study is to determine the impact of wild bird population movement and related environmental factors on the prevalence of Salmonella and Campylobacter on grazing animals of farmlands through fecal contamination. During this first project year, efforts were given to establish project team, farm sites, and test procedures. Project meetings were conducted at each collaborating institution to discuss plans for farm and laboratory activities. For farm management, a total of 14 pastures were fenced to each house 12 sheep or goats. For Objective 1, each farm site was equipped with a set of open water tubs and feed pans that are routinely refilled with clean water and grains to feed animals and attract wild birds. The month of May-June and October-November were selected to conduct the proposed 6-week experiments. For objective 2, each site was managed similar to Objective 1; however, animals were feed mainly by grazing and water was supplied using nipple-waterers. For fecal pathogen analysis, a total of 1,300 fecal samples of farm animals along with water samples from each sites were collected for pathogen detection. In addition, 130 wild birds were captured and had fecal samples collected for microbiological tests to establish pathogen levels in wild bird populations at the farm sites. Data on bird populations and activities were also collected.
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IMPACT: 2006/09/01 TO 2007/08/31<BR>
On-farm food safety management is critical for food and public health protection. Previously, wildlife has been considered as a source of on-farm contamination; however, no report has directly assessed the impact of wild birds on foodborne pathogen transmission or methods for managing this risk. The lack of strategies to avoid contacts between migratory birds and farm animals further compounds the fear of bird-transmitted human diseases. We anticipate this project will generate knowledge of bird control and pathogen transmission with applicability for improving agricultural practices