51
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Van Hoorebeke S, Van Immerseel F, Schulz J, Hartung J, Harisberger M, Barco L, Ricci A, Theodoropoulos G, Xylouri E, De Vylder J, Ducatelle R, Haesebrouck F, Pasmans F, de Kruif A, Dewulf J. Determination of the within and between flock prevalence and identification of risk factors for Salmonella infections in laying hen flocks housed in conventional and alternative systems. Prev Vet Med 2010; 94:94-100. [DOI: 10.1016/j.prevetmed.2009.11.022] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2009] [Revised: 11/23/2009] [Accepted: 11/29/2009] [Indexed: 11/16/2022]
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52
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Scientific Opinion on a quantitative estimation of the public health impact of setting a new target for the reduction of Salmonella in laying hens. EFSA J 2010. [DOI: 10.2903/j.efsa.2010.1546] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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53
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Mueller‐Doblies D, Carrique‐Mas J, Sayers A, Davies R. A comparison of the efficacy of different disinfection methods in eliminating
Salmonella
contamination from turkey houses. J Appl Microbiol 2010; 109:471-479. [DOI: 10.1111/j.1365-2672.2010.04667.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- D. Mueller‐Doblies
- Food and Environmental Safety Department, Veterinary Laboratories Agency Weybridge, New Haw, Addlestone, Surrey, UK
| | - J.J. Carrique‐Mas
- Food and Environmental Safety Department, Veterinary Laboratories Agency Weybridge, New Haw, Addlestone, Surrey, UK
| | - A.R. Sayers
- Centre for Epidemiology and Risk Analysis, Veterinary Laboratories Agency Weybridge, New Haw, Addlestone, Surrey, UK
| | - R.H. Davies
- Food and Environmental Safety Department, Veterinary Laboratories Agency Weybridge, New Haw, Addlestone, Surrey, UK
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54
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Wales AD, McLaren IM, Bedford S, Carrique-Mas JJ, Cook AJC, Davies RH. Longitudinal survey of the occurrence of Salmonella in pigs and the environment of nucleus breeder and multiplier pig herds in England. Vet Rec 2009; 165:648-57. [DOI: 10.1136/vr.165.22.648] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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55
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Volkova VV, Bailey RH, Rybolt ML, Dazo-Galarneau K, Hubbard SA, Magee D, Byrd JA, Wills RW. Inter-relationships of Salmonella Status of Flock and Grow-Out Environment at Sequential Segments in Broiler Production and Processing. Zoonoses Public Health 2009; 57:463-75. [DOI: 10.1111/j.1863-2378.2009.01263.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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56
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Jarquin R, Hanning I, Ahn S, Ricke SC. Development of rapid detection and genetic characterization of salmonella in poultry breeder feeds. SENSORS (BASEL, SWITZERLAND) 2009; 9:5308-23. [PMID: 22346699 PMCID: PMC3274138 DOI: 10.3390/s90705308] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Revised: 06/21/2009] [Accepted: 06/25/2009] [Indexed: 11/17/2022]
Abstract
Salmonella is a leading cause of foodborne illness in the United States, with poultry and poultry products being a primary source of infection to humans. Poultry may carry some Salmonella serovars without any signs or symptoms of disease and without causing any adverse effects to the health of the bird. Salmonella may be introduced to a flock by multiple environmental sources, but poultry feed is suspected to be a leading source. Detecting Salmonella in feed can be challenging because low levels of the bacteria may not be recovered using traditional culturing techniques. Numerous detection methodologies have been examined over the years for quantifying Salmonella in feeds and many have proven to be effective for Salmonella isolation and detection in a variety of feeds. However, given the potential need for increased detection sensitivity, molecular detection technologies may the best candidate for developing rapid sensitive methods for identifying small numbers of Salmonella in the background of large volumes of feed. Several studies have been done using polymerase chain reaction (PCR) assays and commercial kits to detect Salmonella spp. in a wide variety of feed sources. In addition, DNA array technology has recently been utilized to track the dissemination of a specific Salmonella serotype in feed mills. This review will discuss the processing of feeds and potential points in the process that may introduce Salmonella contamination to the feed. Detection methods currently used and the need for advances in these methods also will be discussed. Finally, implementation of rapid detection for optimizing control methods to prevent and remove any Salmonella contamination of feeds will be considered.
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Affiliation(s)
- Robin Jarquin
- Dept. of Poultry Science, University of Arkansas, Fayetteville, AR 72704, USA; E-Mail:
- Research and Development, Cobb-Vantress Incorporated, P.O. BOX 1030, Siloam Springs, AR 72761, USA
| | - Irene Hanning
- Dept. of Food Science, University of Arkansas, Fayetteville, AR 72704, USA; E-Mail:
| | - Soohyoun Ahn
- Food Science and Technology Program, Arkansas State University, State University, AR 72467, USA; E-Mail:
| | - Steven C. Ricke
- Dept. of Poultry Science, University of Arkansas, Fayetteville, AR 72704, USA; E-Mail:
- Dept. of Food Science, University of Arkansas, Fayetteville, AR 72704, USA; E-Mail:
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57
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Huneau-Salaün A, Marianne C, Sophie LB, Françoise L, Isabelle P, Sandra R, Virginie M, Philippe F, Nicolas R. Risk factors for Salmonella enterica subsp. enterica contamination in 519 French laying hen flocks at the end of the laying period. Prev Vet Med 2009; 89:51-8. [DOI: 10.1016/j.prevetmed.2009.01.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2007] [Revised: 01/19/2009] [Accepted: 01/20/2009] [Indexed: 10/21/2022]
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58
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JOHNY ANUPKOLLANOOR, BASKARAN SANGEETHAANANDA, CHARLES ANUSUSAN, AMALARADJOU MARYANNEROSHNI, DARRE MICHAELJ, KHAN MAZHARI, HOAGLAND THOMASA, SCHREIBER DAVIDT, DONOGHUE ANNIEM, DONOGHUE DANJ, VENKITANARAYANAN KUMAR. Prophylactic Supplementation of Caprylic Acid in Feed Reduces Salmonella Enteritidis Colonization in Commercial Broiler Chicks†. J Food Prot 2009. [DOI: 10.4315/0362-028x-72.4.722] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Salmonella Enteritidis is a major foodborne pathogen for which chickens serve as reservoir hosts. Reducing Salmonella Enteritidis carriage in chickens would reduce contamination of poultry meat and eggs with this pathogen. We investigated the prophylactic efficacy of feed supplemented with caprylic acid (CA), a natural, generally recognized as safe eight-carbon fatty acid, for reducing Salmonella Enteritidis colonization in chicks. One hundred commercial day-old chicks were randomly divided into five groups of 20 birds each: CA control (no Salmonella Enteritidis, CA), positive control (Salmonella Enteritidis, no CA), negative control (no Salmonella Enteritidis, no CA), and 0.7 or 1% CA. Water and feed were provided ad libitum. On day 8, birds were inoculated with 5.0 log CFU of Salmonella Enteritidis by crop gavage. Six birds from each group were euthanized on days 1, 7, and 10 after challenge, and Salmonella Enteritidis populations in the cecum, small intestine, cloaca, crop, liver, and spleen were enumerated. The study was replicated three times. CA supplementation at 0.7 and 1% consistently decreased Salmonella Enteritidis populations recovered from the treated birds. Salmonella Enteritidis counts in the tissue samples of CA-treated chicks were significantly lower (P < 0.05) than those of control birds on days 7 and 10 after challenge. Feed intake and body weight did not differ between the groups. Histological examination revealed no pathological changes in the cecum and liver of CA-supplemented birds. The results suggest that prophylactic CA supplementation through feed can reduce Salmonella Enteritidis colonization in day-old chicks and may be a useful treatment for reducing Salmonella Enteritidis carriage in chickens.
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Affiliation(s)
- ANUP KOLLANOOR JOHNY
- 1Department of Animal Science, University of Connecticut, Storrs, Connecticut 06269
| | | | - ANU SUSAN CHARLES
- 1Department of Animal Science, University of Connecticut, Storrs, Connecticut 06269
| | | | - MICHAEL J. DARRE
- 1Department of Animal Science, University of Connecticut, Storrs, Connecticut 06269
| | - MAZHAR I. KHAN
- 2Department of Pathobiology, University of Connecticut, Storrs, Connecticut 06269
| | - THOMAS A. HOAGLAND
- 1Department of Animal Science, University of Connecticut, Storrs, Connecticut 06269
| | - DAVID T. SCHREIBER
- 1Department of Animal Science, University of Connecticut, Storrs, Connecticut 06269
| | - ANNIE M. DONOGHUE
- 3U.S. Department of Agriculture, Agricultural Research Service, Poultry Production and Product Safety Research Unit, Fayetteville, Arkansas 72701
| | - DAN J. DONOGHUE
- 4Center for Excellence in Poultry Science, University of Arkansas, Fayetteville, Arkansas 72701, USA
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59
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Mueller-Doblies D, Sayers AR, Carrique-Mas JJ, Davies RH. Comparison of sampling methods to detect Salmonella infection of turkey flocks. J Appl Microbiol 2009; 107:635-45. [PMID: 19302307 DOI: 10.1111/j.1365-2672.2009.04230.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS To compare the efficiency of various sampling methods for detection of Salmonella in turkey flocks. METHODS AND RESULTS In a field study that compared various sampling methods one pair of boot swabs taken from the whole turkey house provided suitably sensitive results for fattening and rearing flocks and was no less sensitive than two pairs, each from half the house, tested as a pooled sample. The sensitivity was further enhanced by adding a dust sample. The dust sample appeared to be particularly useful in flocks with a low prevalence, especially in breeding flocks, and was more sensitive than a method which used five pairs of boot swabs per flock. Combined incubation of a boot swab and a dust sample showed no interference between the two sample types and a maximum sensitivity of detection. Litter samples and commercial sponge drag swabs provided a lower level of detection. CONCLUSIONS A single pair of boot swabs taken from the whole house is recommended for routine sampling of commercial rearing or fattening flocks. An additional dust sample could be added to increase detection in flocks with a low prevalence or in breeding flocks, but adding an additional pair of boot swabs would not increase detection compared with a single pair. SIGNIFICANCE AND IMPACT OF THE STUDY This study demonstrates that significant efficiencies can be made in sampling programmes for detection of Salmonella in turkey flocks without detracting from the sensitivity. Similar studies are recommended for other poultry sectors, particularly in chicken breeding flocks.
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Affiliation(s)
- D Mueller-Doblies
- Food and Environmental Safety Department, Veterinary Laboratories Agency Weybridge, New Haw, Addlestone, Surrey, UK
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60
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Marin C, Hernandiz A, Lainez M. Biofilm development capacity of Salmonella strains isolated in poultry risk factors and their resistance against disinfectants. Poult Sci 2009; 88:424-31. [DOI: 10.3382/ps.2008-00241] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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61
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Johny AK, Darre M, Hoagland T, Schreiber D, Donoghue A, Donoghue D, Venkitanarayanan K. Antibacterial Effect of Trans-Cinnamaldehyde on Salmonella Enteritidis and Campylobacter jejuni in Chicken Drinking Water ,. J APPL POULTRY RES 2008. [DOI: 10.3382/japr.2008-00051] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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62
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63
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Pedersen TB, Olsen JE, Bisgaard M. Persistence of Salmonella Senftenberg in poultry production environments and investigation of its resistance to desiccation. Avian Pathol 2008; 37:421-7. [PMID: 18622860 DOI: 10.1080/03079450802216561] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Most Salmonella serovars, including Salmonella enterica subsp. enterica serovar Senftenberg (S. Senftenberg), are tolerant to desiccation and able to colonize and persist in feed mills. In addition, they may survive cleaning and disinfection procedures used on poultry farms. The present study was conducted to investigate the survival of S. Senftenberg in broiler parent stock farms and broiler farms. The isolates from one of the parent stock farms investigated only differed by a single band in fluorescent amplified fragment-length polymorphism analysis and had identical pulsed-field gel electrophoresis profiles, indicating that a S. Senftenberg clone had persisted for more than 2 years, despite cleaning, disinfection, desiccation and depopulation, and was subsequently able to infect Salmonella-free layers. Isolates from the same house on a different broiler parent stock farm were found to be identical by amplified fragment-length polymorphism analysis and pulsed-field gel electrophoresis although the farm tested negative for Salmonella 55 times over a period of 18 months between the two positive samplings. An assay was developed to investigate the survival of 34 S. Senftenberg isolates during desiccation at approximately 38% relative humidity. On average, the viability of S. Senftenberg isolates decreased by 1000-fold over 35 days. The persistent clones were no more resistant to desiccation than the other isolates investigated. However, S. Senftenberg was more resistant to desiccation than an isolate of Pantoea agglomerans commonly found on poultry feed-processing lines. This study demonstrates the risk of persistence of feed-associated serovars such as S. Senftenberg.
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Affiliation(s)
- Tina Broennum Pedersen
- Department of Veterinary Pathobiology, Faculty of Life Sciences, University of Copenhagen, Frederiksberg C, Denmark.
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64
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Jacob J, Griggs J, Bender J. Characterization of Small-Scale Antibiotic-Free Broiler Production in Minnesota. J APPL POULTRY RES 2008. [DOI: 10.3382/japr.2007-00057] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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65
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Microbiological risk assessment in feedingstuffs for food‐producing animals ‐ Scientific Opinion of the Panel on Biological Hazards. EFSA J 2008; 6:720. [DOI: 10.2903/j.efsa.2008.720] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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66
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Shahada F, Chuma T, Okamoto K, Sueyoshi M. Temporal Distribution and Genetic Fingerprinting of Salmonella in Broiler Flocks from Southern Japan. Poult Sci 2008; 87:968-72. [DOI: 10.3382/ps.2007-00455] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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67
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Carrique-Mas JJ, Davies RH. Salmonella Enteritidis in commercial layer flocks in Europe: legislative background, on-farm sampling and main challenges. BRAZILIAN JOURNAL OF POULTRY SCIENCE 2008. [DOI: 10.1590/s1516-635x2008000100001] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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68
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Gast RK. Serotype-Specific and Serotype-Independent Strategies for Preharvest Control of Food-Borne Salmonella in Poultry. Avian Dis 2007; 51:817-28. [PMID: 18251388 DOI: 10.1637/8090-081807.1] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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69
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Myint MS, Johnson YJ, Paige JC, Bautista DA. A cross-sectional study of bacterial contamination in plant-protein feed from feed stores in Northern Virginia and Maryland. Anim Feed Sci Technol 2007. [DOI: 10.1016/j.anifeedsci.2006.08.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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70
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Gradel KO, Jørgensen JC, Andersen JS, Corry JEL. Monitoring the efficacy of steam and formaldehyde treatment of naturally Salmonella-infected layer houses. J Appl Microbiol 2004; 96:613-22. [PMID: 14962142 DOI: 10.1111/j.1365-2672.2004.02198.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS To monitor if a temperature-humidity-time treatment found to be effective in eliminating Salmonella in laboratory trials (Gradel et al. 2003) was efficient against Salmonella in naturally infected layer houses. METHODS AND RESULTS Six layer houses with natural Salmonella infections were steam treated in a download period, aiming at >or=60 degrees C and 100% relative humidity (RH) during a 24-h period, with or without the addition of 30 ppm formaldehyde. In addition, two control layer houses were disinfected chemically. Salmonella samples taken from predetermined sites before and after treatment were tested qualitatively for Salmonella and coliforms. Samples with indicator bacteria (feed inoculated with Escherichia coli or Enterococcus faecalis and faeces with naturally occurring E. coli and enterococci) were placed during steam-treatment at 12 sites in each house (where the temperature was logged at 5-min intervals) and tested for surviving bacteria. Generally, the field test results confirmed the results of laboratory tests, especially when 30 ppm formaldehyde was added to the steam. In well-sealed houses, the recommended temperature-humidity-time scheme was accomplished at a minimum of 10 cm above floor level within 1 h. CONCLUSIONS A steam treatment of >or=60 degrees C and 100% RH during a 24-h period with the addition of 30 ppm formaldehyde at the beginning of the process is recommended for eliminating Salmonella from naturally infected poultry layer houses. SIGNIFICANCE AND IMPACT OF THE STUDY A specific recommendation for the elimination of Salmonella in poultry houses can be given.
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Affiliation(s)
- K O Gradel
- Department of Poultry, Fish and Fur-bearing Animals, Danish Institute for Food and Veterinary Research, Aarhus, Denmark.
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71
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Suresh T, Hatha AM, Srinivasan D, Srinivasan S, Lakshmanaperumalsamy P. Salmonella Cross-contamination in Retail Chicken Outlets and the Efficacy of Spice Extracts on Salmonella enteritidis Growth Inhibition on Various Surfaces. Microbes Environ 2004. [DOI: 10.1264/jsme2.19.286] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
| | - Abdulla Mohamed Hatha
- Department of Biology, School of Pure and Applied Sciences, The University of the South Pacific
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72
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Ricke SC. Perspectives on the use of organic acids and short chain fatty acids as antimicrobials. Poult Sci 2003; 82:632-9. [PMID: 12710485 DOI: 10.1093/ps/82.4.632] [Citation(s) in RCA: 479] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Organic acids have a long history of being utilized as food additives and preservatives for preventing food deterioration and extending the shelf life of perishable food ingredients. Specific organic acids have also been used to control microbial contamination and dissemination of foodborne pathogens in preharvest and postharvest food production and processing. The antibacterial mechanism(s) for organic acids are not fully understood, and activity may vary depending on physiological status of the organism and the physicochemical characteristics of the external environment. An emerging potential problem is that organic acids have been observed to enhance survivability of acid sensitive pathogens exposed to low pH by induction of an acid tolerance response and that acid tolerance may be linked to increased virulence. Although this situation has implications regarding the use of organic acids, it may only apply to circumstances in which reduced acid levels have induced resistance and virulence mechanisms in exposed organisms. Evaluating effectiveness of organic acids for specific applications requires more understanding general and specific stress response capabilities of foodborne pathogens. Development and application of molecular tools to study pathogen behavior in preharvest and postharvest food production environments will enable dissection of specific bacterial genetic regulation involved in response to organic acids. This could lead to the development of more targeted strategies to control foodborne pathogens with organic acids.
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Affiliation(s)
- S C Ricke
- Department of Poultry Science, Texas A&M University, College Station, Texas 77843-2472, USA.
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73
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Davies RH, Breslin M. Persistence of Salmonella enteritidis phage type 4 in the environment and arthropod vectors on an empty free-range chicken farm. Environ Microbiol 2003; 5:79-84. [PMID: 12558590 DOI: 10.1046/j.1462-2920.2003.00387.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The persistence of S. Enteritidis PT4 was studied on a free-range breeding chicken farm which had been depopulated following identification of the organism in breeding birds. The site was sampled periodically for 26 months after depopulation and the organism was found to persist in litter, dried faeces and feed, but not in dust within empty poultry houses, for the whole of that period. Salmonella Enteritidis PT4 was also found in soil samples after 8 months but not 13 months and in faeces from wild mice, foxes and cats but not wild birds or badgers. The organism was also found in adult and larval forms of ground beetles and centipedes. Addition of pullets to a contaminated pen or inclusion of contaminated litter, feed or beetles/larvae to feed did not result in acquisition of infection by birds.
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Affiliation(s)
- Robert H Davies
- Department of Bacterial Diseases, Veterinary Laboratories Agency-Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK.
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74
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Gradel KO, Rattenborg E. A questionnaire-based, retrospective field study of persistence of Salmonella Enteritidis and Salmonella Typhimurium in Danish broiler houses. Prev Vet Med 2003; 56:267-84. [PMID: 12507854 DOI: 10.1016/s0167-5877(02)00211-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A questionnaire-based, retrospective field study was conducted in 78 Danish broiler houses (analytical units) on 42 farms. In spring 1997, all these broiler houses had been infected with Salmonella Enteritidis, phage type 8, and/or Salmonella Typhimurium, definitive-type 66, by day-old chicks delivered from the same hatchery. Because these two salmonella types had not been detected in the Danish broiler sector before and the broiler houses were infected in a period of low salmonella prevalence, the study could focus on farm-related factors, without being distorted by other salmonella infections. The same person visited all 78 broiler houses, and farm-related factors were listed both from personal observations and by interrogating the person in charge of attending to the broilers. Additional factors (noted at the visits) were recorded in a later telephone interview. Altogether, 187 variables were analyzed.Broiler houses were divided into single-infection houses (which had one or both of the salmonella types in only one crop), and multiple-infection houses (where infection occurred in multiple crops). This was done both generally and separately for each of the salmonella types. Factors associated with house status-but that were beyond the control of the farmer-were the salmonella type and the percentage of salmonella positive samples in the first crop. Factors which could be controlled by the farmer and which were associated with reduced prevalence of multiple-infection houses included antiseptic soap and water for washing hands in the anteroom, hygiene barriers when removing dead broilers, gravel alongside the broiler house, systematic checks of indoor rodent-bait depots, and combined surface and pulse-fogging disinfection.
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Affiliation(s)
- Kim O Gradel
- Danish Veterinary Institute, Department for Poultry, Fish, and Fur-Bearing Animals, Hangøvej 2, 8200 Aarhus N, Denmark.
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75
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Davison S, Benson CE, Munro DS, Rankin SC, Ziegler AE, Eckroade RJ. The role of disinfectant resistance of Salmonella enterica serotype enteritidis in recurring infections in Pennsylvania egg quality assurance program monitored flocks. Avian Dis 2003; 47:143-8. [PMID: 12713169 DOI: 10.1637/0005-2086(2003)047[0143:trodro]2.0.co;2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The Pennsylvania egg quality assurance program (PEQAP) has made major gains in the reduction of Salmonella enterica serotype enteritidis (S. enteritidis). However, S. enteritidis continues to be a major food safety concern for the commercial egg laying industry. Despite intensive control efforts through PEQAP, some commercial egg layer houses still remain positive for S. enteritidis. The primary objective of this study was to determine whether S. enteritidis isolates obtained from historically environmentally S. enteritidis-positive houses were resistant to commonly used disinfectants. Archived S. enteritidis isolates (environmental, rodent, or egg) were compared with recently obtained isolates from the environment, rodents, or eggs from the same S. enteritidis-positive house. In addition, the isolates were compared with archived isolates from those premises that appeared to have eliminated S. enteritidis from their layer facilities. The official methods of the use-dilution analysis of the Association of Official Analytical Chemists were used to evaluate each disinfectant product. Two phenolic, one quaternary ammonium, and one combination product containing quaternary ammonium and formaldehyde were evaluated, in addition to one sodium hypochlorite detergent. All products diluted according to the manufacturers' recommendations killed the S. enteritidis isolates in this test system. There was no difference in susceptibility or resistance to the disinfectants used between the isolates from those facilities that remained S. enteritidis-positive and those that appeared to have eliminated S. enteritidis from their facility.
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Affiliation(s)
- Sherrill Davison
- Laboratory of Avian Medicine and Pathology, University of Pennsylvania, Kennett Square, PA 19438, USA
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76
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Baloda SB, Christensen L, Trajcevska S. Persistence of a Salmonella enterica serovar typhimurium DT12 clone in a piggery and in agricultural soil amended with Salmonella-contaminated slurry. Appl Environ Microbiol 2001; 67:2859-62. [PMID: 11375208 PMCID: PMC92952 DOI: 10.1128/aem.67.6.2859-2862.2001] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Prevalence of Salmonella enterica on a Danish pig farm presenting recurrent infections was investigated. A comparison of the pulsed-field gel electrophoresis patterns of fecal isolates from piggeries, waste slurry, and agricultural soil amended with Salmonella-contaminated animal waste (slurry) and subclinical isolates from the same farm (collected in 1996 and later) showed identical patterns, indicating long-term persistence of the Salmonella enterica serovar Typhimurium DT12 clone in the herd environment. Furthermore, when Salmonella-contaminated slurry was disposed of on the agricultural soil (a common waste disposal practice), the pathogen was isolated up to 14 days after the spread, indicating potentially high risks of transmission of the pathogen in the environment, animals, and humans.
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Affiliation(s)
- S B Baloda
- Danish Veterinary Laboratory, DK-1790 Copenhagen V, Denmark.
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77
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Yang SE, Yu RC, Chou CC. Influence of holding temperature on the growth and survival of Salmonella spp. and Staphylococcus aureus and the production of staphylococcal enterotoxin in egg products. Int J Food Microbiol 2001; 63:99-107. [PMID: 11205959 DOI: 10.1016/s0168-1605(00)00416-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
In this study, growth and survival of Salmonella spp. and Staphylococcus aureus in steamed egg and scrambled egg held at 5, 18, 22, 37, 55 and 60 degrees C are investigated. The production of staphylococcal enterotoxin in steamed egg is also examined. Results reveal that Salmonella spp. and Staph. aureus in the egg products multiply best at 37 degrees C, followed closely by 22 and 18 degrees C. Neither pathogen showed growth in the egg products held at 5 degrees C. Initial inoculation dose, holding temperature and holding time affected the population of both organisms found in the egg products. Staphylococcal enterotoxin A (SEA) and B (SEB) are detected only in the egg products held at 37 or 22 degrees C. After holding at 37 degrees C for 36 h, scrambled egg inoculated with ca. 5.0 log cfu/g Staph. aureus contains the highest levels of SEA (> 64 ng/g) and SEB (> 64 ng/g). Although Salmonella spp. and Staph. aureus grow better in steamed eggs than in scrambled eggs, production of staphylococcal enterotoxin, in general, was higher in scrambled eggs than in steamed eggs. On the other hand, a repaid destruction of the test organisms in steamed eggs held at 60 degrees C was observed. Holding the steamed eggs at 60 degrees C, Salmonella spp. and Staph. aureus with an initial population of ca. 5.9 and 5.6 log cfu/g, respectively, reduced to a non-detectable level in 1 h.
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Affiliation(s)
- S E Yang
- Graduate Institute of Food Science and Technology, National Taiwan University, Taipei, ROC
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78
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Barbezange C, Ermel G, Ragimbeau C, Humbert F, Salvat G. Some safety aspects of Salmonella vaccines for poultry: in vivo study of the genetic stability of three Salmonella typhimurium live vaccines. FEMS Microbiol Lett 2000; 192:101-6. [PMID: 11040436 DOI: 10.1111/j.1574-6968.2000.tb09366.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Live vaccine strains of Salmonella should be avirulent, immunogenic and genetically stable. Some isolates of three commercially available live vaccine strains of Salmonella typhimurium, sampled during a study on their persistence in a vaccinated flock of chickens, were analyzed for genetic stability using macrorestriction analysis of their genome. Two out of the three vaccine strains showed genetic instabilities. Two of the 51 isolates of Zoosaloral vaccine strain and nine of the 32 analyzed isolates of chi(3985), a genetically modified organism, were variants and showed different macrorestriction profiles.
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Affiliation(s)
- C Barbezange
- AFSSA-Ploufragan, Unit HQPAP, P.O. Box 53, Zoopôle, 22440, Ploufragan, France
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79
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Borgen K, Sørum M, Kruse H, Wasteson Y. Persistence of vancomycin-resistant enterococci (VRE) on Norwegian broiler farms. FEMS Microbiol Lett 2000; 191:255-8. [PMID: 11024272 DOI: 10.1111/j.1574-6968.2000.tb09348.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Five Norwegian broiler farms previously identified as housing broilers carrying vancomycin-resistant enterococci (VRE) were examined for the presence of VRE 4 years after avoparcin was banned. Environmental samples were obtained from empty, cleaned broiler houses. Faecal samples were collected weekly from the flock housed after the environmental sampling. The hatchery from where the chicks originated was also sampled. VRE were found to be present in the farm environment after depopulation and cleanup of the broiler houses. Within 3 weeks after introduction to the farm, all broiler flocks tested positive for VRE. VRE were not isolated from the hatchery.
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Affiliation(s)
- K Borgen
- Department of Pharmacology, Microbiology and Food Hygiene, The Norwegian School of Veterinary Science, Oslo, Norway.
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80
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Singer RS, Jeffrey JS, Carpenter TE, Cooke CL, Atwill ER, Johnson WO, Hirsh DC. Persistence of cellulitis-associated Escherichia coli DNA fingerprints in successive broiler chicken flocks. Vet Microbiol 2000; 75:59-71. [PMID: 10865152 DOI: 10.1016/s0378-1135(00)00205-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Avian cellulitis in broiler chickens is primarily caused by Escherichia coli. Previous research found that the E. coli isolates of cellulitis origin were unique to each ranch, suggesting that these E. coli were endemic within the ranch environment. To test the hypothesis that the E. coli associated with cellulitis are endemic in the litter of the broiler house, we designed a study to determine whether E. coli DNA fingerprints associated with cellulitis persist over successive flocks that are grown in the same house. In addition, we assessed the impact of different cleaning and disinfection strategies on this persistence. Two broiler houses were followed on each of five farms over 3-4 flocks. A total of 353 E. coli isolates from cellulitis lesions were analyzed in this study, and 314 of these isolates (89%) were DNA fingerprinted by PFGE. In each ranch, there were several DNA fingerprint patterns that were present over successive flocks, regardless of the cleaning and disinfection strategy utilized. Isolates persisted as long as 191 days, implying that these E. coli are capable of persisting in the broiler house environment for long periods of time. In addition, these E. coli isolates were associated with cellulitis lesions in successive flocks. Thus, the isolates of E. coli that are associated with cellulitis in broiler chickens appear to be endemic in the litter environment of the broiler house.
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Affiliation(s)
- R S Singer
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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81
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Sandvang D, Jensen LB, Baggesen DL, Baloda SB. Persistence of a Salmonella enterica serotype typhimurium clone in Danish pig production units and farmhouse environment studied by pulsed field gel electrophoresis (PFGE). FEMS Microbiol Lett 2000; 187:21-5. [PMID: 10828394 DOI: 10.1111/j.1574-6968.2000.tb09130.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The clonal relationship among Salmonella enterica serotype Typhimurium isolates from selected pig production units in Denmark was investigated by the pulsed field gel electrophoresis (PFGE) typing method to determine environmental survival and spread of Salmonella in different herds. Thirty-four Typhimurium isolated during 1996-1998 from porcine faeces and environmental samples from three pig farms designated 1, 3 and 5 were characterised by PFGE using two restriction enzymes. Farm 5 supplied piglets to farm 1 and the herds were located close to each other. Results of PFGE analysis showed both intra- and inter-relationships, i.e. identical PFGE patterns among the faecal and environmental isolates from farm 1 and farm 5. All the isolates from farm 3 irrespective of the source showed identical PFGE patterns, but were different from samples from farms 1 and 5. This study indicates spread between farms and survival of a farm-specific clone. Furthermore, identical PFGE patterns of isolates from piglet supplier and finisher herds indicate that the farrow-to-grower herd of farm 5 was sub-clinically infected prior to delivery to farm 1 and thereby caused the transmission of Salmonella.
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Affiliation(s)
- D Sandvang
- Danish Veterinary Laboratory, Bülowsvej 27, DK-1790 V, Copenhagen, Denmark.
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82
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Rose N, Beaudeau F, Drouin P, Toux JY, Rose V, Colin P. Risk factors for Salmonella persistence after cleansing and disinfection in French broiler-chicken houses. Prev Vet Med 2000; 44:9-20. [PMID: 10727741 DOI: 10.1016/s0167-5877(00)00100-8] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A prospective survey was carried out in 86 broiler houses in western France to identify risk factors for Salmonella persistence in French broiler houses. The Salmonella status of the house after cleansing and disinfection, was assessed from gauze-swab samples taken from the walls, feeders, ventilation system and bedding (analysed with classical bacteriological methods). Thirty three (38%) houses had at least one contaminated sample and were classified as Salmonella-contaminated houses in the logistic regression. The absence of a terminal disinfection and a disinfection procedure performed by the farm staff rather than a contractor were positively related to the Salmonella contamination of the house after cleansing and disinfection. The risk for Salmonella persistence after decontamination was increased if rodents were observed by the farmer, if a large part of the access area to the house was accessible to trucks, and if a disease leading to a treatment occurred in the previous flock.
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Affiliation(s)
- N Rose
- AFSSA-Ploufragan, BP 53, F22440, Ploufragan, France.
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83
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Hinton MH. Infections and intoxications associated with animal feed and forage which may present a hazard to human health. Vet J 2000; 159:124-38. [PMID: 10712800 DOI: 10.1053/tvjl.1999.0412] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Animal feed or forage may be the source of a limited number of infections for farm animals that could lead to human illness. Likely organisms include Salmonella enterica, Toxoplasma gondii, Trichinella spiralis and possibly the agent of bovine spongiform encephalopathy. The risk to human health from other infectious agents which may contaminate either feed or forage appear to be either negligible, e.g. Bacillus anthracis and Mycobacterium bovis, or non-existent, e.g. Clostridium botulinum toxin and Listeria monocytogenes. Mycotoxins present in animal feed can result in foods of animal origin also containing them. This risk is well recognized but has yet to be quantified accurately and in some instances the risk may be of theoretical rather than practical importance. Pesticides, agricultural and industrial chemicals, heavy metals and radionuclides may pollute animal feed and forages. The methods available for controlling pollution from these sources are well understood from a technical point of view although the effective implementation of controls can be difficult.
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Affiliation(s)
- M H Hinton
- Department of Clinical Veterinary Science, University of Bristol, Langford, North Somerset, BS40 5DT, UK
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84
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SURESH T, SRINIVASAN D, HATHA A, LAKSHMANAPERUMALSAMY P. The Incidence, Antibiotic Resistance and Survival of Salmonella and Escherichia coli Isolated from Broiler Chicken Retail Outlets. Microbes Environ 2000. [DOI: 10.1264/jsme2.2000.173] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- T. SURESH
- Department of Environmental Sciences,Bharathiar University,Coimbatore-641 046,India
| | - D. SRINIVASAN
- Department of Microbiology,Sree Narayanaguru College,Coimbatore-641 105,India
| | - A.A.M. HATHA
- Department of Aquaculture and Fishery Microbiology,M.E.S.Ponnani College,Ponnani-679 586,Kerala,India
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85
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Holt PS, Mitchell BW, Seo KH, Gast RK. Use of Negative Air Ionization for Reducing Airborne Levels of Salmonella enterica serovar enteritidis in a Room Containing Infected Caged Layers. J APPL POULTRY RES 1999. [DOI: 10.1093/japr/8.4.440] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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86
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Rose N, Beaudeau F, Drouin P, Toux JY, Rose V, Colin P. Risk factors for Salmonella enterica subsp. enterica contamination in French broiler-chicken flocks at the end of the rearing period. Prev Vet Med 1999; 39:265-77. [PMID: 10327442 DOI: 10.1016/s0167-5877(99)00002-1] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Broiler-chicken are often Salmonella carriers. However, these bacteria are responsible for major food-borne human infection, in which poultry-meat products are frequently implicated. In order to prevent Salmonella spread during the slaughtering process, control measures should be implemented at the farm level to reduce the prevalence before slaughtering. The objective of this study was to identify the risk factors for Salmonella contamination in French commercial broiler flocks at the end of the rearing period. A prospective study was carried out in 1996 and 1997 on 86 broiler flocks located in western France. The Salmonella status of the flocks was assessed by means of litter swabs and dust samples analyzed with classical bacteriological methods. Sixty flocks (70%) had at least one contaminated environmental sample and were classified as Salmonella-contaminated flocks. Logistic regression was used to assess association of managerial practices, general hygiene and results of environmental Salmonella recovery, with the odds that the flock itself would be Salmonella-contaminated at the end of the rearing period. Salmonella contamination of the house before placing day-old chicks and the Salmonella contamination of day-old chicks were significantly related to Salmonella contamination of the flock at the end of the rearing period. The risk for Salmonella contamination of the flock was increased when feed trucks parked near the entrance of the change room and when feed meal, instead of small pellets, was provided at the start.
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87
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Limawongpranee S, Hayashidani H, Okatani AT, Ono K, Hirota C, Kaneko K, Ogawa M. Prevalence and persistence of Salmonella in broiler chicken flocks. J Vet Med Sci 1999; 61:255-9. [PMID: 10331198 DOI: 10.1292/jvms.61.255] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cecal contents of 2,345 broiler chickens consisting of 28 flocks originated from 12 farms were examined for the prevalence of Salmonella to know the actual status of infection with Salmonella in the chicken flocks. Salmonella was isolated from 336 (14.3%) samples. From these isolates, eight serovars were identified. Of the 336 Salmonella isolates, 242 (72.0%) were serotyped as S. Blockley, 60 (17.9%) S. Hadar, 15 (4.5%) S. Bredeney, nine (2.7%) S. Schwarzengrund, four (1.2%) S. Anatum, three (0.9%) S. Enteritidis, two (0.6%) S. Ohio, and one (0.3%) S. Livingstone. The same serovars of Salmonella were repeatedly found in the chickens from the same farms. S. Typhimurium and S. Enteritidis were detected in pooled broken eggshell samples collected from the hatchery. Analysis of plasmid profiles revealed 11 patterns of S. Blockley and seven patterns of S. Hadar. Strains of the same plasmid profiles of S. Blockley were isolated repeatedly from the same farm over one year after the first isolation.
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Affiliation(s)
- S Limawongpranee
- Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Japan
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88
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Gast RK, Mitchell BW, Holt PS. Application of negative air ionization for reducing experimental airborne transmission of Salmonella enteritidis to chicks. Poult Sci 1999; 78:57-61. [PMID: 10023747 DOI: 10.1093/ps/78.1.57] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Electrostatic space chargers were used to impart a negative charge to airborne dust particles and thereby cause them to be attracted to grounded surfaces. To determine whether negative air ionization could affect the airborne transmission of Salmonella enteritidis, chicks were housed in four controlled-environment isolation cabinets in which airflow was directed across an unoccupied central area from one ("upstream") group of birds to another ("downstream") group. Negative air ionizers were installed in two of these cabinets. In three replicate trials, groups of chicks were placed in the upstream ends of the transmission cabinets and orally inoculated with S. enteritidis at 1 wk of age. On the following day, 1-d-old chicks were placed in the downstream ends of the cabinets. When chicks were sampled at 3 and 8 d postinoculation, S. enteritidis was found on the surface of 89.6% of the downstream chicks from cabinets without negative air ionizers, but on only 39.6% of the downstream chicks in the presence of the ionizers. Similarly, S. enteritidis was recovered from the ceca of 53.1% of sampled downstream chicks in cabinets without ionizers, but from only 1.0% of the ceca of chicks in cabinets in which ionizers were installed. The presence of the ionizers was also associated with reduced levels of circulating airborne dust particles. Reducing airborne dust levels may thus offer an opportunity to limit the spread of S. enteritidis infections throughout poultry flocks.
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Affiliation(s)
- R K Gast
- USDA, ARS, Southeast Poultry Research Laboratory, Athens, Georgia 30605, USA.
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89
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Gast RK, Holt PS. Persistence of Salmonella enteritidis from one day of age until maturity in experimentally infected layer chickens. Poult Sci 1998; 77:1759-62. [PMID: 9872575 DOI: 10.1093/ps/77.12.1759] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In each of two replicate trials, 1-d-old chicks were inoculated orally with a phage type 13 Salmonella enteritidis isolate (resistant to nalidixic acid). Although S. enteritidis was found in the livers, spleens, and ceca of all sampled chicks at 1 wk postinoculation, colonization generally persisted beyond 4 wk postinoculation only in the ceca. Nearly half of the remaining hens were still shedding S. enteritidis in their feces at 24 wk of age, but only 1 of 62 hens laid eggs that were internally contaminated with S. enteritidis during the initial 4 to 6 wk of egg production. Chickens exposed to S. enteritidis shortly after hatching can apparently remain infected until maturity, at which time they might produce contaminated eggs or spread the infection to other susceptible, previously unexposed hens.
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Affiliation(s)
- R K Gast
- USDA, Agricultural Research Service, Southeast Poultry Research Laboratory, Athens, Georgia 30605, USA.
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90
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Ha S, Maciorowski K, Kwon Y, Jones F, Ricke S. Indigenous feed microflora and Salmonella typhimurium marker strain survival in poultry mash diets containing varying levels of protein. Anim Feed Sci Technol 1998. [DOI: 10.1016/s0377-8401(98)00216-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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