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Baptista DQ, Borsoi A, Reischak D, Nascimento ACO, Montesino LO, Camillo SCA, Abreu DLC, Pereira VLA. Salmonella Serovars Isolated from Poultry Breeding Flocks under the Brazilian Official Control Programme Between 2016 and 2018. BRAZILIAN JOURNAL OF POULTRY SCIENCE 2023. [DOI: 10.1590/1806-9061-2022-1646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- DQ Baptista
- Universidade Federal Fluminense, Brazil; Ministério da Agricultura, Pecuária e Abastecimento, Brazil
| | - A Borsoi
- Ministério da Agricultura, Pecuária e Abastecimento, Brazil
| | - D Reischak
- Ministério da Agricultura, Pecuária e Abastecimento, Brazil
| | - ACO Nascimento
- Ministério da Agricultura, Pecuária e Abastecimento, Brazil
| | - LO Montesino
- Ministério da Agricultura, Pecuária e Abastecimento, Brazil
| | - SCA Camillo
- Ministério da Agricultura, Pecuária e Abastecimento, Brazil
| | - DLC Abreu
- Universidade Federal Fluminense, Brazil
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Dietary Inclusion of a Saccharomyces cerevisiae-Derived Postbiotic Is Associated with Lower Salmonella enterica Burden in Broiler Chickens on a Commercial Farm in Honduras. Microorganisms 2022; 10:microorganisms10030544. [PMID: 35336119 PMCID: PMC8952340 DOI: 10.3390/microorganisms10030544] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 02/16/2022] [Accepted: 02/25/2022] [Indexed: 01/31/2023] Open
Abstract
Postbiotic feed additives may aid foodborne pathogen reduction during poultry rearing. The study objective was to evaluate a postbiotic additive in parallel to an industry control diet and the subsequent associated burden of Salmonella enterica on a single, commercial broiler farm in Honduras. Twelve houses were matched and assigned the standard diet (CON) or standard diet plus postbiotic (SCFP). New litter was placed in each house and retained across flock cycles with sampling prior to each chick placement and three consecutive rearing cycles. At ~33–34 days, 25 ceca were collected on-farm from each house, treatment, and cycle. Salmonella prevalence in litter for CON (30.6%) and SCFP (27.8%) were equivalent; however, Salmonella load within positive samples was lower (p = 0.04) for SCFP (3.81 log10 MPN/swab) compared to CON (5.53 log10 MPN/swab). Cecal prevalence of Salmonella was lower (p = 0.0006) in broilers fed SCFP (3.4%) compared to CON (12.2%). Salmonella load within positive ceca were numerically reduced (p = 0.121) by 1.45 log10 MPN/g for SCFP (2.41 log10 MPN/g) over CON (3.86 log10 MPN/g). Estimated burden was lower (p = 0.003) for SCFP flocks (3.80 log10 MPN) compared to CON (7.31 log10 MPN). These data demonstrate the preharvest intervention potential of postbiotics to reduce Salmonella enterica in broiler chickens.
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Chinivasagam HN, Estella W, Rodrigues H, Mayer DG, Tran T, Onysk A, Weyand C, Diallo I, Billington C. Re-used or New Bedding Are Not Drivers of Salmonella Levels and Serovar Emergence in Commercially Farmed Broilers in Australia. FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2022. [DOI: 10.3389/fsufs.2022.816181] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
To inform Salmonella on-farm management during broiler rearing, a 2-year study on two farms compared the Australian practices of new bedding use, partial litter re-use and an alternative, full litter re-use. Six sequential commercial cycles of ~50 days each were tested on each farm, on ~day 7 from placement (litter only), prior to first thin-out, and prior to final removal (litter and ceca). A random number sample collection occurred, defined by shed supports (33, 39), different drinkers, feeders, and shed center. Across the six cycles on both farms, Salmonella levels in ceca just prior to thin-out on full re-use litter were higher (log 3.11 MPN/g, P = 0.008) than for new bedding (log 2.04 MPN/g) and partial re-use (log 2.43 MPN/g) litter (the latter two were not significantly different). Prior to final removal across all practices the Salmonella levels in ceca from new bedding (log 1.72 MPN/g), partial re-use litter (log 1.77 MPN/g), and full re-use litter (log 2.33 MPN/g) were not statistically different, suggesting no effect of litter practice. The Salmonella levels in litter prior to the first (log 1.96–2.31 MPN/g) and second (log 2.24–2.48 MPN/g) removals were also not statistically different. The emergence of Salmonella serovars in the partitioned chicken-free grow-out end (back) of all sheds at ~day 7 did not suggest carry-over. Both the pattern of emergence of Salmonella serovars and Salmonella levels in litter ~day 7 in the brooder-end with chickens (front), suggested the Salmonella present were due to flock contribution and not practice driven. The dominant Salmonella serovar across cycles on both farms was S. Sofia (75 and 77% isolates) followed by S. Typhimurium (11 and 17%). Irrespective of initial serovars, Salmonella Sofia rapidly gained dominance and displaced 14 other serovars including S. Typhimurium on both farms. This study demonstrates that the litter practices are not the major driver of Salmonella prevalence in broiler farming, supporting the commercial re-use of bedding as a sustainable farming practice in Australia. The major contributor of Salmonella load in production is the Salmonella status of the incoming flock, indicating this is the key area to focus future control measures.
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Ansari F, Bokaie S, Peighambari SM, Fallah MH, Tehrani F, Rajab A, Ghafouri SA, Shabani M, Pourjafar H. Survey of Salmonella infections in broiler farms in Iran during 2013-2014: a cross-sectional study. IRANIAN JOURNAL OF MICROBIOLOGY 2020; 12:404-410. [PMID: 33603994 PMCID: PMC7867690 DOI: 10.18502/ijm.v12i5.4600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Background and Objectives: The aim of this study was to determine the prevalence of Salmonella at broiler breeder farms of Iran and investigate the factors underlying salmonellosis in these farms. This is a cross-sectional investigation conducted in 23 provinces of Iran. Materials and Methods: Fecal samples were collected from 139 broiler breeder farms in the country and standard bacteriological tests were carried out on the samples for the isolation of Salmonella. The serological tests were then applied for the samples that were positive in the bacteriological test. The information on the sampled farms extracted from the Iran GIS-VET Monitoring and Surveillance System was used for the analysis of the risk factors. Results: A total of 11 farms out of the 139 sampled farms were infected with Salmonella with the largest number of infected cases related to Tehran and Fars Provinces. Conclusion: The statistical analysis results showed that flocks with older ages and farms with larger number of houses are at greater risk of Salmonella infection.
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Affiliation(s)
- Fereshteh Ansari
- Evidence-Based Medicine Research Center, Health Management and Safety Promotion Research Institute, Tabriz University of Medical Sciences, Tabriz, Iran.,Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran
| | - Saied Bokaie
- Department of Food Hygiene, School of Veterinary Medicine, University of Tehran, Tehran, Iran
| | | | | | | | | | | | | | - Hadi Pourjafar
- Department of Food Sciences and Nutrition, Maragheh University of Medical Sciences, Maragheh, Iran.,Dietary Supplements and Probiotic Research Center, Alborz University of Medical Sciences, Karaj, Iran
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Vinueza-Burgos C, Ortega-Paredes D, Narváez C, De Zutter L, Zurita J. Characterization of cefotaxime resistant Escherichia coli isolated from broiler farms in Ecuador. PLoS One 2019; 14:e0207567. [PMID: 30951531 PMCID: PMC6450624 DOI: 10.1371/journal.pone.0207567] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 03/27/2019] [Indexed: 12/16/2022] Open
Abstract
Antimicrobial resistance (AR) is a worldwide concern. Up to a 160% increase in antibiotic usage in food animals is expected in Latin American countries. The poultry industry is an increasingly important segment of food production and contributor to AR. The objective of this study was to evaluate the prevalence, AR patterns and the characterization of relevant resistance genes in Extended Spectrum β-lactamases (ESBL) and AmpC-producing E. coli from large poultry farms in Ecuador. Sampling was performed from June 2013 to July 2014 in 6 slaughterhouses that slaughter broilers from 115 farms totaling 384 flocks. Each sample of collected caeca was streaked onto TBX agar supplemented with cefotaxime (3 mg/l). In total, 176 isolates were analyzed for AR patterns by the disk diffusion method and for blaCTX-M, blaTEM, blaCMY, blaSHV, blaKPC, and mcr-1 by PCR and sequencing. ESBL and AmpC E. coli were found in 362 flocks (94.3%) from 112 farms (97.4%). We found that 98.3% of the cefotaxime-resistant isolates were multi-resistant to antibiotics. Low resistance was observed for ertapenem and nitrofurantoin. The most prevalent ESBL genes were the ones belonging to the blaCTX-M group (90.9%), specifically the blaCTX-M-65, blaCTX-M-55 and blaCTX-M-3 alleles. Most of the AmpC strains presented the blaCMY-2 gene. Three isolates showed the mcr-1 gene. Poultry production systems represent a hotspot for AR in Ecuador, possibly mediated by the extensive use of antibiotics. Monitoring this sector in national and regional plans of AR surveillance should therefore be considered.
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Affiliation(s)
- Christian Vinueza-Burgos
- Unidad de Investigación de Enfermedades Transmitidas por Alimentos y Resistencias a los Antibióticos, Facultad de Medicina Veterinaria y Zootecnia, Universidad Central del Ecuador, Quito, Ecuador
| | - David Ortega-Paredes
- Unidad de Investigación de Enfermedades Transmitidas por Alimentos y Resistencias a los Antibióticos, Facultad de Medicina Veterinaria y Zootecnia, Universidad Central del Ecuador, Quito, Ecuador
- Unidad de Investigaciones en Biomedicina, Zurita&Zurita Laboratorios, Quito, Ecuador
| | - Cristian Narváez
- Unidad de Investigación de Enfermedades Transmitidas por Alimentos y Resistencias a los Antibióticos, Facultad de Medicina Veterinaria y Zootecnia, Universidad Central del Ecuador, Quito, Ecuador
| | - Lieven De Zutter
- Department of Veterinary Public Health and Food Safety, Faculty of Veterinary, Ghent University, Merelbeke, Belgium
| | - Jeannete Zurita
- Unidad de Investigaciones en Biomedicina, Zurita&Zurita Laboratorios, Quito, Ecuador
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Poulsen MN, Pollak J, Sills DL, Casey JA, Rasmussen SG, Nachman KE, Cosgrove SE, Stewart D, Schwartz BS. Residential proximity to high-density poultry operations associated with campylobacteriosis and infectious diarrhea. Int J Hyg Environ Health 2017; 221:323-333. [PMID: 29268955 DOI: 10.1016/j.ijheh.2017.12.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 12/13/2017] [Accepted: 12/13/2017] [Indexed: 12/31/2022]
Abstract
Poultry carry zoonotic bacteria that can cause gastroenteritis in humans. Environmental transmission of pathogens from poultry operations may increase gastrointestinal infection risk in surrounding communities. To evaluate associations between residential proximity to high-density poultry operations and individual-level diarrheal illnesses, we conducted a nested case-control study among 514,488 patients in Pennsylvania (2006-2015). Using electronic health records, we identified cases of five gastrointestinal outcomes: three pathogen-specific infections, including Escherichia coli (n = 1425), Campylobacter (n = 567), and Salmonella (n = 781); infectious diarrhea (n = 781); and non-specific diarrhea (2012-2015; n = 28,201). We estimated an inverse-distance squared activity metric for poultry operations based on farm and patient addresses. Patients in the second and fourth (versus first) quartiles of the poultry operation activity metric had increased odds of Campylobacter (AOR [CI], Q2: 1.36 [1.01, 1.82]; Q3: 1.38 [0.98, 1.96]; Q4: 1.75 [1.31, 2.33]). Patients in the second, third, and fourth quartiles had increased odds of infectious diarrhea (Q2: 1.76 [1.29, 2.39]; Q3: 1.76 [1.09, 2.85]; Q4: 1.60 [1.12, 2.30]). Stratification revealed stronger relations of fourth quartile and both Campylobacter and infectious diarrhea in townships, the most rural community type in the study geography. Increasing extreme rainfall in the week prior to diagnosis strengthened fourth quartile Campylobacter associations. The poultry operation activity metric was largely unassociated with E. coli, Salmonella, and non-specific diarrhea. Findings suggest high-density poultry operations may be associated with campylobacteriosis and infectious diarrhea in nearby communities, highlighting additional public health concerns of industrial agriculture.
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Affiliation(s)
- Melissa N Poulsen
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; Department of Epidemiology and Health Services Research, Geisinger, Danville, PA, USA.
| | - Jonathan Pollak
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Deborah L Sills
- Department of Civil and Environmental Engineering, Bucknell University, Lewisburg, PA, USA
| | - Joan A Casey
- Department of Environmental Science, Policy & Management, University of California, Berkeley, CA, USA
| | - Sara G Rasmussen
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Keeve E Nachman
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; Center for a Livable Future, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; Risk Sciences and Public Policy Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Sara E Cosgrove
- Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA; Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Dalton Stewart
- Department of Civil and Environmental Engineering, Bucknell University, Lewisburg, PA, USA
| | - Brian S Schwartz
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; Department of Epidemiology and Health Services Research, Geisinger, Danville, PA, USA; Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA; Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
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Rajan K, Shi Z, Ricke SC. Current aspects ofSalmonellacontamination in the US poultry production chain and the potential application of risk strategies in understanding emerging hazards. Crit Rev Microbiol 2016; 43:370-392. [DOI: 10.1080/1040841x.2016.1223600] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Kalavathy Rajan
- Center for Food Safety, Department of Food Science, University of Arkansas, Fayetteville, AR, USA
| | - Zhaohao Shi
- Center for Food Safety, Department of Food Science, University of Arkansas, Fayetteville, AR, USA
| | - Steven C. Ricke
- Center for Food Safety, Department of Food Science, University of Arkansas, Fayetteville, AR, USA
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Prevalence and molecular characterization of Salmonella enterica isolates throughout an integrated broiler supply chain in China. Epidemiol Infect 2016; 144:2989-2999. [PMID: 27443305 DOI: 10.1017/s0950268816001515] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
A total of 1145 samples were collected from chicken breeder farms, hatcheries, broiler farms, a slaughterhouse and retail refrigerated chicken stores in an integrated broiler supply chain in Guangdong Province, China, in 2013. One-hundred and two Salmonella enterica strains were isolated and subjected to serotyping, antimicrobial susceptibility testing, virulence profile determination and molecular subtyping by pulsed field gel electrophoresis (PFGE). The contamination rates in samples from breeder farms, hatcheries, broiler farms, the slaughterhouse and retail stores were 1·46%, 4·31%, 7·00%, 62·86% and 54·67%, respectively. The isolated strains of S. enterica belonged to 10 serotypes; most of them were S. Weltevreden (46·08%, 47/102) and S. Agona (18·63%, 19/102). Isolates were frequently resistant to streptomycin (38·2%), tetracycline (36·3%), sulfisoxazole (35·3%) and gentamicin (34·3%); 31·4% of isolates were multidrug resistant. The isolates were screened for 10 virulence factors. The Salmonella pathogenicity island genes avrA, ssaQ, mgtC, siiD, and sopB and the fimbrial gene bcfC were present in 100% of the strains. PFGE genotyping of the 102 S. enterica isolates yielded 24 PFGE types at an 85% similarity threshold. The PFGE patterns show that the genotypes of S. enterica in the production chain are very diverse, but some strains have 100% similarity in different parts of the production chain, which indicates that some S. enterica persist throughout the broiler supply chain.
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Flockhart L, Pintar K, Cook A, McEwen S, Friendship R, Kelton D, Pollari F. Distribution of Salmonella in Humans, Production Animal Operations and a Watershed in a FoodNet Canada Sentinel Site. Zoonoses Public Health 2016; 64:41-52. [PMID: 27345363 DOI: 10.1111/zph.12281] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Indexed: 11/28/2022]
Abstract
Salmonella is an important human pathogen, and production animals as well as water are known potential sources. This study helped provide insight into the epidemiology of Salmonella by comparing Salmonella strains found in humans to those detected in production animals and water in the same geographic area and time frame. Salmonella was found in 55% of broiler, 30% of swine, 13% of dairy, and 10% of beef manure samples and 23% of water samples. At the farm level, Salmonella was found on 93% of broiler, 81% of swine, 32% of beef and 30% of dairy farms. Salmonella strains of importance to public health were found in all sources tested; however, they appeared to be more common in the broilers. A number of the farms in this study were mixed farms, in that they had more than one production animal species on the farm. At both the sample and farm levels, beef-only farms had a significantly lower Salmonella prevalence (5% and 7%, respectively) than beef farms with additional production animal species (e.g. poultry) (12% and 42%, respectively) (P ≤ 0.05). Additionally, a number of mixed farms had more than one commodity sampled for this study and similar Salmonella strains by phage type and PFGE were found in the poultry and the other sampled commodity on the farm. This information can help inform the evidence base needed to help target interventions and modify best practices in production agriculture.
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Affiliation(s)
- L Flockhart
- Public Health Agency of Canada, Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Guelph, ON, Canada
| | - K Pintar
- Public Health Agency of Canada, Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Ottawa, ON, Canada
| | - A Cook
- Public Health Agency of Canada, Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Guelph, ON, Canada
| | - S McEwen
- Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | - R Friendship
- Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | - D Kelton
- Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | - F Pollari
- Public Health Agency of Canada, Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Guelph, ON, Canada
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Prevalence and fimbrial genotype distribution of poultry Salmonella isolates in China (2006 to 2012). Appl Environ Microbiol 2013; 80:687-93. [PMID: 24242234 DOI: 10.1128/aem.03223-13] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
In this study, a total of 323 Salmonella enterica strains were isolated from 3,566 rectal swab samples of 51 poultry farms in seven regions of 12 provinces of China between 2006 and 2012. The prevalences of Salmonella sp. carriage were 12.4% in geese (66 positive/533 samples), 10.4% in turkeys (32/309), 9.8% in chickens (167/1,706), 6.8% in ducks (41/601), and 4.1% in pigeons (17/417), respectively. These isolates belonged to 20 serovars, in which the most frequent serovars were S. enterica serovar Gallinarum biovar Pullorum (herein, S. Pullorum) (55 isolates, 17.0%), S. enterica serovar Typhimurium (50 isolates, 15.5%), and S. enterica serovar Enteritidis (39 isolates, 12.1%). Overall, S. Typhimurium was the most commonly detected serovar; among the individual species, S. Pullorum was most commonly isolated from chickens, S. Enteritidis was most common in ducks, S. Typhimurium was most common in geese and pigeons, and S. enterica serovar Saintpaul was most common in turkeys. PCR determination of 20 fimbrial genes demonstrated the presence of bcfD, csgA, fimA, stdB, and sthE genes and the absence of staA and stgA genes in these isolates, and other loci were variably distributed, with frequency values ranging from 11.8 to 99.1%. These 323 Salmonella isolates were subdivided into 41 different fimbrial genotypes, and of these isolate, 285 strains (88.2%) had 12 to 14 fimbrial genes. Our findings indicated that the Salmonella isolates from different poultry species were phenotypically and genetically diverse and that some fimbrial genes are more frequently associated with serovars or serogroups.
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Vereen E, Lowrance RR, Jenkins MB, Adams P, Rajeev S, Lipp EK. Landscape and seasonal factors influence Salmonella and Campylobacter prevalence in a rural mixed use watershed. WATER RESEARCH 2013; 47:6075-6085. [PMID: 23969398 DOI: 10.1016/j.watres.2013.07.028] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 07/08/2013] [Accepted: 07/18/2013] [Indexed: 06/02/2023]
Abstract
Salmonella and Campylobacter prevalence in stream networks of the Satilla River Basin (SRB) were monitored monthly from August 2007 to August 2009 to study relationships between these pathogens and land use, presence of poultry houses and wastewater treatment plant (WWTP) discharge. Salmonella and Campylobacter were detected at all 10 stream sites and the three sites at the sole wastewater treatment plant (WWTP) in the study area. In all, 43% (129/299) and 62% (96/156) of samples were positive for Salmonella and Campylobacter, respectively, with detection frequency increasing in downstream sites with more poultry production and influence of WWTP discharge. Both Salmonella and Campylobacter detection frequencies were positively associated with the number of poultry houses in the subwatersheds, but agricultural land use as a proportion of the watershed was not a significant predictor of either pathogen. Fecal indicator bacterial levels were assessed and evaluated for their ability to predict the presence of pathogens. Of those examined, enterococci was most predictive; of the 129 samples positive for Salmonella, 88% (113/129) were detected when enterococci were above EPA single sample threshold (61 CFU 100 ml(-1)); and of the 96 samples positive for Campylobacter, 90% (86/96) were detected when enterococci levels exceeded this level. Comparatively, Escherichia coli concentrations were above EPA single sample thresholds in 38% (49/129) of the positive Salmonella samples. Detection of the pathogens throughout the watershed indicated that there was potential for waterborne transmission especially in downstream areas that were more likely to have recreational users.
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Affiliation(s)
- Ethell Vereen
- University of Georgia, Odum School of Ecology, Athens, GA 30602, USA; USDA-Agricultural Research Service, Southeast Watershed Research Unit, Tifton, GA 31793, USA
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