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Collins A, Collins C. Epidemiology Tools to Evaluate the Control of Proliferative Enteropathy in Commercial Pig Herds. Animals (Basel) 2024; 14:1357. [PMID: 38731361 PMCID: PMC11083394 DOI: 10.3390/ani14091357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 04/23/2024] [Accepted: 04/29/2024] [Indexed: 05/13/2024] Open
Abstract
Proliferative enteropathy (PE) is characterized by diarrhea and reduced weight gains in growing pigs and intestinal hemorrhage in finishers. Vaccination, antibiotic medication, and improved hygiene can control PE, but their efficacy depends upon the epidemiology of PE. This study monitored the timing and severity of PE in 84 commercial pens across seven treatments, including disinfection, vaccination, no treatment, medication with olaquindox (50, 25 and 12.5 ppm), and combined disinfection and vaccination. Vaccination with or without lime disinfection suppressed clinical signs of PE and reduced the number of excreted L. intracellularis relative to untreated pigs housed in cleaned or cleaned and disinfected pens between 9 and 17 weeks of age. Continuous olaquindox mediation to 17 weeks of age prevented L. intracellularis infection, leaving finisher pigs naïve. These finisher pigs suffered an outbreak of hemorrhagic enteropathy with significant reductions in weight gain, feed intake, and mortalities of 4.6%. Over the 13 week grow/finish period, vaccinated pigs housed in disinfected pens showed significantly higher weight gain and feed intake relative to all other treatments, equating to a weight gain difference of between 3.6 and 3.9 kg per pig. Monitoring the immune response and fecal excretion of L. intracellularis in pens of pigs enabled effective PE control strategies to be evaluated on the farm.
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Affiliation(s)
- Alison Collins
- New South Wales Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Menangle, NSW 2568, Australia
| | - Cherie Collins
- Rivalea Australia, P.O. Box 78, Corowa, NSW 2646, Australia;
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Daniel AGS, Pereira CER, Dorella F, Pereira FL, Laub RP, Andrade MR, Barrera-Zarate JA, Gabardo MP, Otoni LVA, Macedo NR, Correia PA, Costa CM, Vasconcellos AO, Wagatsuma MM, Marostica TP, Figueiredo HCP, Guedes RMC. Synergic Effect of Brachyspira hyodysenteriae and Lawsonia intracellularis Coinfection: Anatomopathological and Microbiome Evaluation. Animals (Basel) 2023; 13:2611. [PMID: 37627402 PMCID: PMC10451556 DOI: 10.3390/ani13162611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Revised: 08/01/2023] [Accepted: 08/08/2023] [Indexed: 08/27/2023] Open
Abstract
Brachyspira hyodysenteriae and Lawsonia intracellularis coinfection has been observed in the diagnostic routine; however, no studies have evaluated their interaction. This study aimed to characterize lesions and possible synergisms in experimentally infected pigs. Four groups of piglets, coinfection (CO), B. hyodysenteriae (BRA), L. intracellularis (LAW), and negative control (NEG), were used. Clinical signals were evaluated, and fecal samples were collected for qPCR. At 21 days post infection (dpi), all animals were euthanized. Gross lesions, bacterial isolation, histopathology, immunohistochemistry, and fecal microbiome analyses were performed. Diarrhea started at 12 dpi, affecting 11/12 pigs in the CO group and 5/11 pigs in the BRA group. Histopathological lesions were significantly more severe in the CO than the other groups. B. hyodysenteriae was isolated from 11/12 pigs in CO and 5/11 BRA groups. Pigs started shedding L. intracellularis at 3 dpi, and all inoculated pigs tested positive on day 21. A total of 10/12 CO and 7/11 BRA animals tested positive for B. hyodysenteriae by qPCR. A relatively low abundance of microbiota was observed in the CO group. Clinical signs and macroscopic and microscopic lesions were significantly more severe in the CO group compared to the other groups. The presence of L. intracellularis in the CO group increased the severity of swine dysentery.
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Affiliation(s)
- Amanda G. S. Daniel
- Department of Veterinary Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (A.G.S.D.); (C.E.R.P.); (F.D.); (R.P.L.); (M.R.A.); (J.A.B.-Z.); (M.P.G.); (L.V.A.O.); (P.A.C.); (C.M.C.); (A.O.V.); (M.M.W.); (T.P.M.)
| | - Carlos E. R. Pereira
- Department of Veterinary Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (A.G.S.D.); (C.E.R.P.); (F.D.); (R.P.L.); (M.R.A.); (J.A.B.-Z.); (M.P.G.); (L.V.A.O.); (P.A.C.); (C.M.C.); (A.O.V.); (M.M.W.); (T.P.M.)
| | - Fernanda Dorella
- Department of Veterinary Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (A.G.S.D.); (C.E.R.P.); (F.D.); (R.P.L.); (M.R.A.); (J.A.B.-Z.); (M.P.G.); (L.V.A.O.); (P.A.C.); (C.M.C.); (A.O.V.); (M.M.W.); (T.P.M.)
| | - Felipe L. Pereira
- Department of Preventive Veterinary Medicine, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (F.L.P.); (H.C.P.F.)
| | - Ricardo P. Laub
- Department of Veterinary Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (A.G.S.D.); (C.E.R.P.); (F.D.); (R.P.L.); (M.R.A.); (J.A.B.-Z.); (M.P.G.); (L.V.A.O.); (P.A.C.); (C.M.C.); (A.O.V.); (M.M.W.); (T.P.M.)
| | - Mariana R. Andrade
- Department of Veterinary Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (A.G.S.D.); (C.E.R.P.); (F.D.); (R.P.L.); (M.R.A.); (J.A.B.-Z.); (M.P.G.); (L.V.A.O.); (P.A.C.); (C.M.C.); (A.O.V.); (M.M.W.); (T.P.M.)
| | - Javier A. Barrera-Zarate
- Department of Veterinary Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (A.G.S.D.); (C.E.R.P.); (F.D.); (R.P.L.); (M.R.A.); (J.A.B.-Z.); (M.P.G.); (L.V.A.O.); (P.A.C.); (C.M.C.); (A.O.V.); (M.M.W.); (T.P.M.)
| | - Michelle P. Gabardo
- Department of Veterinary Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (A.G.S.D.); (C.E.R.P.); (F.D.); (R.P.L.); (M.R.A.); (J.A.B.-Z.); (M.P.G.); (L.V.A.O.); (P.A.C.); (C.M.C.); (A.O.V.); (M.M.W.); (T.P.M.)
| | - Luísa V. A. Otoni
- Department of Veterinary Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (A.G.S.D.); (C.E.R.P.); (F.D.); (R.P.L.); (M.R.A.); (J.A.B.-Z.); (M.P.G.); (L.V.A.O.); (P.A.C.); (C.M.C.); (A.O.V.); (M.M.W.); (T.P.M.)
| | - Nubia R. Macedo
- College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA;
| | - Paula A. Correia
- Department of Veterinary Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (A.G.S.D.); (C.E.R.P.); (F.D.); (R.P.L.); (M.R.A.); (J.A.B.-Z.); (M.P.G.); (L.V.A.O.); (P.A.C.); (C.M.C.); (A.O.V.); (M.M.W.); (T.P.M.)
| | - Camila M. Costa
- Department of Veterinary Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (A.G.S.D.); (C.E.R.P.); (F.D.); (R.P.L.); (M.R.A.); (J.A.B.-Z.); (M.P.G.); (L.V.A.O.); (P.A.C.); (C.M.C.); (A.O.V.); (M.M.W.); (T.P.M.)
| | - Amanda O. Vasconcellos
- Department of Veterinary Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (A.G.S.D.); (C.E.R.P.); (F.D.); (R.P.L.); (M.R.A.); (J.A.B.-Z.); (M.P.G.); (L.V.A.O.); (P.A.C.); (C.M.C.); (A.O.V.); (M.M.W.); (T.P.M.)
| | - Mariane M. Wagatsuma
- Department of Veterinary Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (A.G.S.D.); (C.E.R.P.); (F.D.); (R.P.L.); (M.R.A.); (J.A.B.-Z.); (M.P.G.); (L.V.A.O.); (P.A.C.); (C.M.C.); (A.O.V.); (M.M.W.); (T.P.M.)
| | - Thaire P. Marostica
- Department of Veterinary Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (A.G.S.D.); (C.E.R.P.); (F.D.); (R.P.L.); (M.R.A.); (J.A.B.-Z.); (M.P.G.); (L.V.A.O.); (P.A.C.); (C.M.C.); (A.O.V.); (M.M.W.); (T.P.M.)
| | - Henrique C. P. Figueiredo
- Department of Preventive Veterinary Medicine, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (F.L.P.); (H.C.P.F.)
| | - Roberto M. C. Guedes
- Department of Veterinary Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 130161-970, Brazil; (A.G.S.D.); (C.E.R.P.); (F.D.); (R.P.L.); (M.R.A.); (J.A.B.-Z.); (M.P.G.); (L.V.A.O.); (P.A.C.); (C.M.C.); (A.O.V.); (M.M.W.); (T.P.M.)
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Hankel J, Sander S, Muthukumarasamy U, Strowig T, Kamphues J, Jung K, Visscher C. Microbiota of vaccinated and non-vaccinated clinically inconspicuous and conspicuous piglets under natural Lawsonia intracellularis infection. Front Vet Sci 2022; 9:1004506. [DOI: 10.3389/fvets.2022.1004506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 10/03/2022] [Indexed: 11/13/2022] Open
Abstract
Lawsonia (L.) intracellularis is a widespread, economically important bacterium causing the porcine proliferative enteropathy (PPE). In this study, we evaluated intestinal microbiota of naturally exposed L. intracellularis-positive pigs under standardized conditions. To obtain three independent repetitions, 27 L. intracellularis-infected pigs (19.0 ± 1.50 kg body weight) from one farm were divided into three groups at an age of 7 to 8 weeks (nine pigs/group). Pigs were either vaccinated against L. intracellularis via oral drenching on their 21st day of life (attenuated live vaccine) or non-vaccinated and selected according to clinical findings (pigs without deviating fecal consistency or with moderate to soft fecal consistency). Comparison of the clinically inconspicuous piglets that differed regarding their vaccination status showed fewer significant differences in fecal microbiota composition. The vaccination led to an overall enrichment of bacterial species belonging to the order Clostridiales, while species of the genus Collinsella and Prevotella were decreased. Several bacterial species belonging to the order Bacteroidales, mainly of the family Prevotellacecae, often closely matching Prevotella copri differed significantly between non-vaccinated clinically inconspicuous and conspicuous piglets. Whether those bacterial species play a role in mitigating the severity of an L. intracellularis infection remains to be defined.
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François-Brazier C, Payebien A, Manson C, Lefaux B, Quintard B. PREVALENCE OF LAWSONIA INTRACELLULARIS INFECTION IN NONHUMAN PRIMATES AND PEST RODENTS IN A ZOOLOGICAL COLLECTION. J Zoo Wildl Med 2021; 52:680-688. [PMID: 34130411 DOI: 10.1638/2018-0185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/01/2021] [Indexed: 11/21/2022] Open
Abstract
In 2016 and 2017, Lawsonia intracellularis was isolated from several pileated gibbons (Hylobates pileatus) presenting with diarrhea in Mulhouse Zoo (eastern France). To this day, infection with this bacterium has rarely been described in nonhuman primates (NHP) in captivity or in the wild and there are no data about the prevalence or transmission of the disease. This study focuses on finding the prevalence of this infection amongst Mulhouse Zoo's NHP collection and trying to identify a source of contamination responsible for this epizooty. Forty-eight real-time PCR were conducted on feces from all NHP species in the zoo and on small mammals trapped in the NHP housing structures. No NHP was experiencing symptoms at the time of the study, however test results showed that Lawsonia intracellularis can be found in 61.76% (21/34) of the group total (n = 34) and the prevalence even increases to 92.3% (12/13) in the Lemuriform infraorder (n = 13). In small mammals (n = 14), prevalence of the bacterium is 57.17% (8/14) including 77.78% in rodents (7/9). The results of this study show that several NHP species are healthy carriers and some species of small mammals can be considered as a potential source of contamination. Because of the difficulty encountered trying to isolate the bacterium, it is plausible that infections caused by Lawsonia intracellularis have been underdiagnosed to this day, and that it could be an emerging disease in Europe. Therefore, using real-time PCR to search for this bacterium seems essential in case of diarrhea occurring in nonhuman primates. Moreover, even though further studies on contamination sources need to be conducted, the issue of the presence of rodents in NHP housing structures has to be taken very seriously and tackled with the utmost care.
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Affiliation(s)
| | - Audrey Payebien
- Laboratoire vétérinaire départemental du Haut-Rhin, 68025 Colmar, France
| | - Christine Manson
- Laboratoire vétérinaire départemental du Haut-Rhin, 68025 Colmar, France
| | - Brice Lefaux
- Parc zoologique et botanique de Mulhouse, 68100 Mulhouse, France
| | - Benoît Quintard
- Parc zoologique et botanique de Mulhouse, 68100 Mulhouse, France
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Muwonge A, Karuppannan AK, Opriessnig T. Probiotics mediated gut microbiota diversity shifts are associated with reduction in histopathology and shedding of Lawsonia intracellularis. Anim Microbiome 2021; 3:22. [PMID: 33663618 PMCID: PMC7931366 DOI: 10.1186/s42523-021-00084-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 02/11/2021] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Clinical intervention during bacterial infections in farm animals such as pigs commonly includes the use of antimicrobials. With the rise of antimicrobial resistance and the attempts to reduce the use of antibiotics in food animals, effective alternatives are urgently needed to reduce or even remove pathogens and disease risks. Improving clinical outcomes and overall pig health by using probiotics appears attractive. However, reliable data sets on the efficacy of probiotics are scarce. The obligate intracellular bacterium Lawsonia intracellularis is widespread in pigs and associated with severe enteropathy, mainly in the ileum, commonly resulting in substantial reduction in weight gain. The impact of three in-feed probiotics and a commercial live L. intracellularis vaccine was compared in a pig challenge model. Probiotic treatment was associated with reduced L. intracellularis fecal shedding and reduced gut lesions. Here, the bacterial microbiota of the ileum of these pigs was characterized with 16S rRNA gene sequencing and was subsequently analyzed with bioinformatics tools. RESULTS The greatest microbial richness was observed in the probiotic treated group T03-LAW, which accounted for 87% of richness observed in the study. Treatment had a significant impact on both the microbiota structure and taxonomic profile in the ileum, explaining between 26 and 36% of the structural variation, with the strongest association in the T03-LAW group. Overall, the largest changes were observed for the pigs treated with in-feed Bacillus pumilus; the microbiota of these pigs had the greatest diversity and highest richness. We also observed depleted and enriched core microbiota amongst the groups; however, there was no correlation with clinical characteristics. The results suggest that an increased diversity of the ileal microbiota is associated with a reduction in shedding, i.e. a unit increase in Shannon diversity index resulted in 2.8 log reduction in shedding. CONCLUSIONS Probiotic supplementation of a base feed ration increased ileum microbiota diversity leading to a mitigation of the effects of a pathogenic L. intracellularis challenge. An even and diverse microbiota community benefits pigs infected with L. intracellularis, however, investigations are needed to determine if this is also true for other pathogens. The study unambiguously demonstrates the usefulness of probiotic supplementation in reducing the impact of enteric pathogens and pathogen shedding rates in food animals without the use of antimicrobials.
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Affiliation(s)
- Adrian Muwonge
- The Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, UK
| | - Anbu K Karuppannan
- Vaccine Research Centre-Viral Vaccines, Centre for Animal Health Studies, Tamil Nadu Veterinary and Animal Sciences University, Chennai, India
| | - Tanja Opriessnig
- The Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, UK.
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA.
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Arnold M, Crienen A, Swam H, Berg SV, Jolie R, Nathues H. Correlation of Lawsonia intracellularis positivity in quantitative PCR and herd factors in European pig herds. Porcine Health Manag 2021; 7:13. [PMID: 33482877 PMCID: PMC7821494 DOI: 10.1186/s40813-021-00192-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 01/12/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Lawsonia intracellularis is causing diarrhea, poor growth and sudden death in pigs. It can be found in most pig populations leading to large economic losses worldwide. Many potential risk factors for the occurrence of disease or seropositivity have been described. The current study therefore focused on herd characteristics in European countries associated with direct detection of the pathogen determined by quantitative polymerase chain reaction. RESULTS A median number of less than 30 nursery pigs per pen was correlated to less positive nursery pigs (p < 0.01) and generally less samples positive per herd (p < 0.05) as well as a lower median of genome equivalents determined per herd (p < 0.05). Routine use of zinc oxide at/ around weaning, which was mentioned by 41.0% of all farmers, was correlated to higher number of positive nursery pigs (p < 0.01) as well as higher median genome equivalents determined per herd (p < 0.05). Slatted flooring of more than 78.0% of the surface in nursery units was correlated to lower number of positive animals (p < 0.05) and a lower median of genome equivalents per herd (p < 0.05). A weight of more than 7.8 kg at weaning was correlated to a higher number of positive growing pigs (p < 0.05) as well as general higher number of positive samples/ herd (p < 0.01). CONCLUSIONS Weaning and subsequent accommodation of nursery pigs seem to be of particular importance in prevention of infection with Lawsonia intracellularis and the spread of the pathogen within the herd.
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Affiliation(s)
- Mirjam Arnold
- Clinic for Swine, Department for Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Annelies Crienen
- Center for Diagnostic Solutions, MSD AH Boxmeer, Boxmeer, The Netherlands
| | - Hanny Swam
- Center for Diagnostic Solutions, MSD AH Boxmeer, Boxmeer, The Netherlands
| | | | - Rika Jolie
- Merck Animal Health, Madison, NJ, 07940, USA
| | - Heiko Nathues
- Clinic for Swine, Department for Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
- Department for Clinical Veterinary Medicine, Farm Animal Clinic, Vetsuisse-Faculty, University of Bern, Bremgartenstrasse 109 a, CH-3012, Bern, Switzerland.
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Cutler R, Gleeson B, Page S, Norris J, Browning G. Antimicrobial prescribing guidelines for pigs. Aust Vet J 2020; 98:105-134. [PMID: 32281105 DOI: 10.1111/avj.12940] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 08/19/2019] [Accepted: 09/05/2019] [Indexed: 01/16/2023]
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Arnold M, Crienen A, Swam H, von Berg S, Jolie R, Nathues H. Prevalence of Lawsonia intracellularis in pig herds in different European countries. Porcine Health Manag 2019; 5:31. [PMID: 31890255 PMCID: PMC6918559 DOI: 10.1186/s40813-019-0137-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 11/28/2019] [Indexed: 11/10/2022] Open
Abstract
Background Lawsonia intracellularis causes large economic losses in the pig industry worldwide. Pigs suffer from reduced daily weight gain, poor feed conversion ratio and increased mortality. The number of affected animals and herds in Europe remains unknown. This study will provide an overview of the prevalence of Lawsonia intracellularis in herds with a history of diarrhoea in different European countries and thereby identify country specific differences. Results Out of the 144 herds sampled in Germany, Denmark, Spain, the Netherlands and the United Kingdom, 90.3% (79.2-100.0%) contained at least one positive faecal sample on quantitative polymerase chain reaction (qPCR). Of the 6450 nursery, growing and finishing pigs of the previously mentioned herds, 26.2% (15.9-41.5%) of the animals were tested positive in faecal samples. Enzyme linked immunosorbent assay (ELISA) results of 60 herds were 91.7% (70-100%) positive. The percentage of positive samples in these 1791 blood samples was 31.6% (20.3-51.0%). Herd prevalence did not differ significantly by qPCR or ELISA. Significant differences between the countries were found regarding: Within-herd prevalence- qPCR: Samples from Denmark were more often positive than samples of Spain or the United Kingdom. Within-herd prevalence- ELISA: Samples from Denmark were more often positive than samples from Spain and the Netherlands. Affected age category- qPCR: Nursery pigs in Denmark were more often positive and shed more genome equivalents than nursery pigs in the other countries. Concentration of detected genome equivalents- qPCR: The concentration of genome equivalents from Lawsonia intracellularis in herds in Denmark was higher compared to all other countries. Conclusion A widespread of Lawsonia intracellularis in the six European countries was confirmed, whereby a large part of the positive animals only excreted small amounts of genome equivalents. Country specific differences were found with Denmark in particular diagnosing more Lawsonia intracellularis then the other countries. Herd data collected in this study needs to be analysed to get more information about possible reasons for the differences found between the countries.
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Affiliation(s)
- Mirjam Arnold
- 1Clinic for Swine, Department for Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Annelies Crienen
- Center for Diagnostic Solutions, MSD AH Boxmeer, Boxmeer, The Netherlands
| | - Hanny Swam
- Center for Diagnostic Solutions, MSD AH Boxmeer, Boxmeer, The Netherlands
| | | | - Rika Jolie
- 4Merck Animal Health, Madison, NJ 07940 USA
| | - Heiko Nathues
- 1Clinic for Swine, Department for Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Bern, Switzerland
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Opriessnig T, Karuppannan AK, Beckler D, Ait-Ali T, Cubas-Atienzar A, Halbur PG. Bacillus pumilus probiotic feed supplementation mitigates Lawsonia intracellularis shedding and lesions. Vet Res 2019; 50:85. [PMID: 31640784 PMCID: PMC6806562 DOI: 10.1186/s13567-019-0696-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 09/11/2019] [Indexed: 01/18/2023] Open
Abstract
The causative agent of ileitis, Lawsonia intracellularis, is commonly associated with diarrhea and reduced weight gain in growing pigs. The effect of in-feed probiotics on L. intracellularis infection dynamics was evaluated. In brief, 70 2.5-week-old-pigs were randomly divided into six groups with 10–20 pigs each. All pigs were fed an age appropriate base ration for the duration of the study, which was supplemented with one of three Bacillus strains including B. amyloliquefaciens (T01), B. licheniformis (T02) and B. pumilus (T03). Another group was orally vaccinated with a commercial live L. intracellularis vaccine (VAC) at 3 weeks of age. At 7 weeks of age, T01-LAW, T02-LAW, T03-LAW, VAC-LAW and the POS-CONTROL groups were challenged with L. intracellularis while the NEG-CONTROL pigs were not challenged. All pigs were necropsied 16 days later. By the time of inoculation, all VAC-LAW pigs had seroconverted and at necropsy 10–65% of the pigs in all other challenged groups were also seropositive. The results indicate a successful L. intracellularis challenge with highest bacterial DNA levels in POS-CONTROL pigs, VAC-LAW pigs and T01-LAW pigs. There was a delay in onset of shedding in T02-LAW and T03-LAW groups, which was reflected in less severe macroscopic and microscopic lesions, reduced intralesional L. intracellularis antigen levels and a lower area under the curve for bacterial shedding. Under the study conditions, two of the probiotics tested suppressed L. intracellularis infection. The obtained findings show the potential of probiotics in achieving antibiotic-free control of L. intracellularis.
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Affiliation(s)
- Tanja Opriessnig
- The Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK. .,Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA.
| | - Anbu K Karuppannan
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | | | - Tahar Ait-Ali
- The Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK
| | - Ana Cubas-Atienzar
- The Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK
| | - Patrick G Halbur
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
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Karuppannan AK, Opriessnig T. Lawsonia intracellularis: Revisiting the Disease Ecology and Control of This Fastidious Pathogen in Pigs. Front Vet Sci 2018; 5:181. [PMID: 30140680 PMCID: PMC6095029 DOI: 10.3389/fvets.2018.00181] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 07/16/2018] [Indexed: 12/29/2022] Open
Abstract
Lawsonia intracellularis is an anaerobic obligate intracellular bacterium infecting the small intestine and infrequently also the large intestine of pigs and other animals including hamsters and horses. The infection is characterized by proliferation, hemorrhage, necrosis, or any combination commonly referred to as "ileitis," affecting the health and production efficacy of farmed pigs. Despite decades of research on this pathogen, the pathogenesis and virulence factors of this organism are not clearly known. In pigs, prophylaxis against L. intracellularis infection is achieved by either administration of subtherapeutic levels of in-feed antibiotic growth promoters or vaccination. While the former approach is considered to be effective in L. intracellularis control, potential regulations on subtherapeutic antibiotics in many countries in the near future may necessitate alternative approaches. The potential of manipulating the gut microbiome of pigs with feed ingredients or supplements to control L. intracellularis disease burden is promising based on the current understanding of the porcine gut microbiome in general, as well as preliminary insights into the disease ecology of L. intracellularis infection accrued over the last 30 years.
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Affiliation(s)
- Anbu K. Karuppannan
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Tanja Opriessnig
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
- The Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, United Kingdom
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Use of flow cytometry and PCR analysis to detect 5-carboxyfluoroscein-stained obligate intracellular bacteria Lawsonia intracellularis invasion of McCoy cells. J Microbiol Methods 2016; 126:60-6. [PMID: 27154728 DOI: 10.1016/j.mimet.2016.04.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Accepted: 04/29/2016] [Indexed: 11/23/2022]
Abstract
In this study, we describe a method to quantify invasion of obligate intracellular bacteria, Lawsonia intracellularis, inside McCoy cells. In immunological research, the cell-permeable fluorescent dye 5'-carboxyfluoroscein succidyl ester (CFSE) is commonly used to quantify eukaryotic cellular proliferation. Instead of using it in this traditional way, we stained L. intracellularis with CFSE dye prior to infection of McCoy cells. Flow cytometry was performed to quantify the percentage of eukaryotic cells which had taken up or were associated with fluorescent bacteria. As obligate intracellular bacteria, they cannot replicate outside of eukaryotic cells and thus qPCR analysis was used to quantify bacterial growth. Indirectly, PCR analysis confirmed invasion rather than adherence to the McCoy cell surface. Fluorescent activated cell sorting (FACS) was used to sort the CFSE(+) (i.e. infected) McCoy cells from the CFSE(-) (i.e. non-infected) McCoy cells and confocal microscopy was used to confirm bacterial invasion and cytosolic localization of CFSE-L. intracellularis. To show that this approach could be used in conjunction with functional assays, we investigated the effect that serum antibodies had on CFSE-bacterial invasion and growth. Instead of blocking invasion, rabbit hyperimmune serum augmented invasion of the bacteria inside McCoy cells and qPCR analysis confirmed bacterial growth over the course of 5days. We conclude that CFSE-labeling of bacteria and qPCR can be used to track and quantify bacterial invasion and may be a valuable tool for studying the invasive properties of bacteria, especially if commercial antibodies are not available. This approach may be adapted for use in other obligate intracellular bacteria and intracellular pathogens.
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Larsen I, Nielsen SS, Olsen JE, Nielsen JP. The efficacy of oxytetracycline treatment at batch, pen and individual level on Lawsonia intracellularis infection in nursery pigs in a randomised clinical trial. Prev Vet Med 2016; 124:25-33. [DOI: 10.1016/j.prevetmed.2015.12.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 12/17/2015] [Accepted: 12/22/2015] [Indexed: 11/30/2022]
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13
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Larsen I, Hjulsager CK, Holm A, Olsen JE, Nielsen SS, Nielsen JP. A randomised clinical trial on the efficacy of oxytetracycline dose through water medication of nursery pigs on diarrhoea, faecal shedding of Lawsonia intracellularis and average daily weight gain. Prev Vet Med 2016; 123:52-59. [DOI: 10.1016/j.prevetmed.2015.12.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 11/30/2015] [Accepted: 12/10/2015] [Indexed: 10/22/2022]
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Nogueira MG, Collins AM, Dunlop RH, Emery D. Effect of the route of administration on the mucosal and systemic immune responses toLawsonia intracellularisvaccine in pigs. Aust Vet J 2015; 93:124-6. [DOI: 10.1111/avj.12305] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/28/2014] [Indexed: 12/01/2022]
Affiliation(s)
- MG Nogueira
- Farm Animal and Veterinary Public Health; University of Sydney; Camden New South Wales Australia
| | - AM Collins
- NSW Department of Primary Industries; Elizabeth Macarthur Agricultural Institute; Narellan New South Wales Australia
| | - RH Dunlop
- Chris Richards and Associates Pty Ltd; East Bendigo Victoria Australia
| | - D Emery
- Farm Animal and Veterinary Public Health; University of Sydney; Camden New South Wales Australia
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Magtoto RL, Vegi A, Wang C, Johnson JK, Ramamoorthy S. Evaluation and use of a serological assay for the detection of antibodies to Lawsonia intracellularisin swine. Int J Vet Sci Med 2014. [DOI: 10.1016/j.ijvsm.2014.08.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Ronaldo L. Magtoto
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Anuradha Vegi
- Department of Veterinary and Microbiological Sciences, N. Dakota State University, Fargo, ND, United States
| | - Chong Wang
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
- Department of Statistics College of Liberal Arts and Sciences, Iowa State University, Ames, IA, United States
| | - John K. Johnson
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Sheela Ramamoorthy
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
- Department of Statistics College of Liberal Arts and Sciences, Iowa State University, Ames, IA, United States
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Smith SH, Wilson AD, Van Ettinger I, MacIntyre N, Archibald AL, Ait-Ali T. Down-regulation of mechanisms involved in cell transport and maintenance of mucosal integrity in pigs infected with Lawsonia intracellularis. Vet Res 2014; 45:55. [PMID: 24885874 PMCID: PMC4031155 DOI: 10.1186/1297-9716-45-55] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 04/22/2014] [Indexed: 11/10/2022] Open
Abstract
Lawsonia intracellularis is an obligate intracellular bacterium, responsible for the disease complex known as proliferative enteropathy (PE). L. intracellularis is associated with intestinal crypt epithelial cell proliferation but the mechanisms responsible are yet to be defined. Microarray analysis was used to investigate the host-pathogen interaction in experimentally infected pigs to identify pathways that may be involved. Ileal samples originating from twenty-eight weaner pigs experimentally challenged with a pure culture of L. intracellularis (strain LR189/5/83) were subjected to microarray analysis. Microarray transcriptional signatures were validated using immunohistochemistry and quantitative real time PCR of selected genes at various time points post challenge. At peak of infection (14 days post challenge) 86% of altered transcripts were down regulated, particularly those involved in maintenance of mucosal integrity and regulation of cell transport. Among the up-regulated transcripts, CD163 and CDK1 were novel findings and considered to be important, due to their respective roles in innate immunity and cellular proliferation. Overall, targeted cellular mechanisms included those that are important in epithelial restitution, migration and protection; maintenance of stable inter-epithelial cell relationships; cell transport of nutrients and electrolytes; innate immunity; and cell cycle.
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Affiliation(s)
| | | | | | | | | | - Tahar Ait-Ali
- The Roslin Institute, University of Edinburgh, Easter Bush Campus, Roslin, Midlothian EH25 9RG, UK.
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Vannucci FA, Gebhart CJ. Recent Advances in Understanding the Pathogenesis of Lawsonia intracellularis Infections. Vet Pathol 2014; 51:465-77. [DOI: 10.1177/0300985813520249] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Proliferative enteropathy is an infectious disease caused by an obligate intracellular bacterium, Lawsonia intracellularis, and characterized by thickening of the intestinal epithelium due to enterocyte proliferation. The disease is endemic in swine herds and has been occasionally reported in various other species. Furthermore, outbreaks among foals began to be reported on breeding farms worldwide within the past 5 years. Cell proliferation is directly associated with bacterial infection and replication in the intestinal epithelium. As a result, mild to severe diarrhea is the major clinical sign described in infected animals. The dynamics of L. intracellularis infection in vitro and in vivo have been well characterized, but little is known about the genetic basis for the pathogenesis or ecology of this organism. The present review focuses on the recent advances regarding the pathogenesis and host-pathogen interaction of L. intracellularis infections.
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Affiliation(s)
- F. A. Vannucci
- Department of Veterinary and Biomedical Science, College of Veterinary Medicine, University of Minnesota, St Paul, MN, USA
| | - C. J. Gebhart
- Department of Veterinary and Biomedical Science, College of Veterinary Medicine, University of Minnesota, St Paul, MN, USA
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Pusterla N, Gebhart C. Lawsonia intracellularis infection and proliferative enteropathy in foals. Vet Microbiol 2013; 167:34-41. [PMID: 23871678 PMCID: PMC7126703 DOI: 10.1016/j.vetmic.2013.06.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 06/25/2013] [Accepted: 06/27/2013] [Indexed: 11/23/2022]
Abstract
Equine proliferative enteropathy (EPE) is a disease of foals caused by the obligate intracellular organism Lawsonia intracellularis. This organism is unique in that it causes proliferation of infected enterocytes, resulting in thickening of the intestinal epithelium, most often the small intestine. This disease affects mainly weanling foals and causes fever, lethargy, peripheral edema, diarrhea, colic and weight loss. The diagnosis of EPE may be challenging and relies on the presence of hypoproteinemia, thickening of segments of the small intestinal wall observed on abdominal ultrasonography, positive serology and molecular detection of L. intracellularis in feces. The epidemiology and genetic basis for pathogenesis for this disease is beginning to be elucidated. Phenotypic traits, genomic features, and gene expression profiles during L. intracellularis infection in vitro and in vivo are presented. In addition, this article reviews the epidemiology, pathological and clinicopathological findings, diagnosis, and control of EPE.
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Affiliation(s)
- Nicola Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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Vannucci FA, Kelley MR, Gebhart CJ. Comparative genome sequencing identifies a prophage-associated genomic island linked to host adaptation of Lawsonia intracellularis infections. Vet Res 2013; 44:49. [PMID: 23826661 PMCID: PMC3716683 DOI: 10.1186/1297-9716-44-49] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 06/07/2013] [Indexed: 11/10/2022] Open
Abstract
Lawsonia intracellularis is an obligate intracellular bacterium and the causative agent of proliferative enteropathy (PE). The disease is endemic in pigs, emerging in horses and has also been reported in a variety of other animal species, including nonhuman primates. Comparing the whole genome sequences of a homologous porcine L. intracellularis isolate cultivated for 10 and 60 passages in vitro, we identified a 18-kb prophage-associated genomic island in the passage 10 (pathogenic variant) that was lost in the passage 60 (non-pathogenic variant). This chromosomal island comprises 15 genes downstream from the prophage DLP12 integrase gene. The prevalence of this genetic element was evaluated in 12 other L. intracellularis isolates and in 53 infected animals and was found to be conserved in all porcine isolates cultivated for up to 20 passages and was lost in isolates cultivated for more than 40 passages. Furthermore, the prophage region was also present in 26 fecal samples derived from pigs clinically affected with both acute and chronic forms of the disease. Nevertheless, equine L. intracellularis isolates evaluated did not harbor this genomic island regardless of the passage in vitro. Additionally, fecal samples from 21 clinically affected horses and four wild rabbits trapped in horse farms experiencing PE outbreaks did not show this prophage-associated island. Although the presence of this prophage-associated island was not essential for a virulent L. intracellularis phenotype, this genetic element was porcine isolate-specific and potentially contributed to the ecological specialization of this organism for the swine host.
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Affiliation(s)
- Fabio A Vannucci
- Department of Veterinary and Biomedical Science, College of Veterinary Medicine, University of Minnesota, St, Paul, MN, USA.
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Vannucci FA, Foster DN, Gebhart CJ. Laser microdissection coupled with RNA-seq analysis of porcine enterocytes infected with an obligate intracellular pathogen (Lawsonia intracellularis). BMC Genomics 2013; 14:421. [PMID: 23800029 PMCID: PMC3718617 DOI: 10.1186/1471-2164-14-421] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 06/18/2013] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Lawsonia intracellularis is an obligate intracellular bacterium and the etiologic agent of proliferative enteropathy. The disease is endemic in pigs, emerging in horses and has been described in various other species including nonhuman primates. Cell proliferation is associated with bacterial replication in enterocyte cytoplasm, but the molecular basis of the host-pathogen interaction is unknown. We used laser capture microdissection coupled with RNA-seq technology to characterize the transcriptional responses of infected enterocytes and the host-pathogen interaction. RESULTS Proliferative enterocytes was associated with activation of transcription, protein biosynthesis and genes acting on the G1 phase of the host cell cycle (Rho family). The lack of differentiation in infected enterocytes was demonstrated by the repression of membrane transporters related to nutrient acquisition. The activation of the copper uptake transporter by infected enterocytes was associated with high expression of the Zn/Cu superoxide dismutase by L. intracellularis. This suggests that the intracellular bacteria incorporate intracytoplasmic copper and express a sophisticated mechanism to cope with oxidative stress. CONCLUSIONS The feasibility of coupling microdissection and RNA-seq was demonstrated by characterizing the host-bacterial interactions from a specific cell type in a heterogeneous tissue. High expression of L. intracellularis genes encoding hypothetical proteins and activation of host Rho genes infers the role of unrecognized bacterial cyclomodulins in the pathogenesis of proliferative enteropathy.
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Affiliation(s)
- Fabio A Vannucci
- Department of Veterinary and Biomedical Science , College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA
| | - Douglas N Foster
- Department of Animal Science, College of Food, Agricultural and Natural Resource Science, University of Minnesota, St. Paul, MN, USA
| | - Connie J Gebhart
- Department of Veterinary and Biomedical Science , College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA
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Vannucci FA, Beckler D, Pusterla N, Mapes SM, Gebhart CJ. Attenuation of virulence of Lawsonia intracellularis after in vitro passages and its effects on the experimental reproduction of porcine proliferative enteropathy. Vet Microbiol 2012; 162:265-9. [PMID: 22939985 DOI: 10.1016/j.vetmic.2012.08.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 07/31/2012] [Accepted: 08/01/2012] [Indexed: 10/28/2022]
Abstract
Non-pathogenic Lawsonia intracellularis variants have been obtained through multiple passages in cell culture but there is no information regarding the number of passages necessary to attenuate a pathogenic isolate. The present study evaluated the susceptibility of pigs to L. intracellularis after 10, 20 and 40 passages in vitro. Three groups (six animals/group) were inoculated with pure culture of L. intracellularis on passage 10, 20 or 40 and one group with placebo. The animals were monitored for clinical signs, fecal shedding and serological IgG response during 28 days post-inoculation. Gross and histologic lesions and the level of infection based on the amount of L. intracellularis-specific antigen in the intestinal mucosa identified by immunohistochemistry were evaluated in two animals from each group on days 14, 21 and 28. Animals inoculated with passages 10 and 20 demonstrated proliferative lesions typical of porcine proliferative enteropathy associated with the presence of Lawsonia-specific antigen in the intestinal mucosa. Passage 40-inoculated pigs did not show proliferative lesions or presence of Lawsonia antigen at any time point throughout the study. Similar patterns of the fecal shedding were observed in passage 10 and 20-infected pigs but those infected with passage 40 shed for a short period. Serological IgG responses in passage 10 and 20-inoculated pigs were detected from day 14 post-infection but not at all in passage 40-inoculated animals. These results demonstrate attenuation of the virulence properties of L. intracellularis between 20 and 40 cell passages in vitro. This information will be valuable for design of future experimental models and for studying the mechanisms involved in the attenuation of L. intracellularis virulence.
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Affiliation(s)
- Fabio A Vannucci
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA.
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Backhans A, Fellström C. Rodents on pig and chicken farms - a potential threat to human and animal health. Infect Ecol Epidemiol 2012; 2:IEE-2-17093. [PMID: 22957130 PMCID: PMC3426328 DOI: 10.3402/iee.v2i0.17093] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 01/20/2012] [Accepted: 01/23/2012] [Indexed: 02/06/2023] Open
Abstract
Rodents can cause major problems through spreading various diseases to animals and humans. The two main species of rodents most commonly found on farms around the world are the house mouse (Mus musculus) and the brown rat (Rattus norvegicus). Both species are omnivorous and can breed year-round under favourable conditions. This review describes the occurrence of pathogens in rodents on specialist pig and chicken farms, which are usually closed units with a high level of bio-security. However, wild rodents may be difficult to exclude completely, even from these sites, and can pose a risk of introducing and spreading pathogens. This article reviews current knowledge regarding rodents as a hazard for spreading disease on farms. Most literature available regards zoonotic pathogens, while the literature regarding pathogens that cause disease in farm animals is more limited.
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Affiliation(s)
- Annette Backhans
- Department of Clinical Sciences, Faculty of Veterinary Medicine and Animal Science, Swedish University of Agricultural Sciences, Uppsala, Sweden
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Hands I, McOrist S, Blunt R, Lawrence K. Current infection patterns of porcine proliferative enteropathy in Great Britain and the Republic of Ireland. Vet Rec 2010; 167:343-4. [PMID: 20802189 DOI: 10.1136/vr.c3763] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- I Hands
- Elanco Animal Health, Priestley Road, Basingstoke, Hampshire.
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Holyoake PK, Emery D, Gonsalves J, Donahoo M, Collins A. Prevalence of antibodies to Lawsonia intracellularis in pig herds in Australia. Aust Vet J 2010; 88:186-8. [PMID: 20529028 DOI: 10.1111/j.1751-0813.2010.00558.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Proliferative enteropathy (PE) of pigs is caused by Lawsonia intracellularis. Clinical severity appears to depend, at least partly, on the infective dose and strain of L. intracellularis. Serological tests are able to detect subclinical disease. The Bioscreen ELISA for detecting L. intracellularis-specific antibodies is widely used to monitor the circulating antibody status of pigs in Australia, but its sensitivity and specificity have not been reported. The aim of the present study was to measure the seroprevalence of antibodies to L. intracellularis in growing pigs in Australia. METHODS Test sera were sourced from 1817 serum samples collected from finisher pigs from 63 herds across Australia in 2001, selected from a larger sample of 180 herds to represent the contribution that each herd size makes to the number of pigs produced. The test sera were the most recent collection of pig sera from all states and samples had been stored at -80 degrees C from 2001 until testing was conducted in 2008. Sera were tested using the BioScreen ELISA. RESULTS All herds tested positive for L. intracellularis-specific antibodies. The mean percentage of positive samples within each herd was 84.2% (range 31.3-100%). CONCLUSIONS Lawsonia intracellularis is endemic in pig herds in Australia and cost-effective strategies to reduce reliance on antibiotics, such as vaccination and/or all-in/all-out pig flow coupled with cleaning and disinfection of pens, are warranted.
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Affiliation(s)
- P K Holyoake
- Industry and Investment NSW, Wagga Wagga Agricultural Institute, Wagga Wagga, New South Wales 2650, Australia.
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Guimarães-Ladeira CV, Palhares MS, Oliveira JSV, Ramirez MA, Guedes RMC. Faecal shedding and serological cross-sectional study of Lawsonia intracellularis in horses in the state of Minas Gerais, Brazil. Equine Vet J 2009; 41:593-6. [PMID: 19803056 DOI: 10.2746/042516409x407639] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
REASON FOR PERFORMING THE STUDY Proliferative enteropathy, caused by the intracellular bacterium Lawsonia intracellularis, has been described in horses in Australia, the USA, Canada and European countries but has not been reported in Latin America. The prevalence of the disease in horses worldwide is unknown. OBJECTIVE To evaluate the presence of subclinical L. intracellularis infection in horses in the state of Minas Gerais, Brazil. METHODS A longitudinal study using serology and PCR for detecting antibodies (IgG) and shedding of L. intracellularis in faecal samples, respectively, was conducted using a total of 223 horses from 14 different horse farms in Minas Gerais, and from the Veterinary School of UFMG equine herds in Minas Gerais. The immunoperoxidase technique in glass slides was used as the serological test. RESULTS Twenty-one horse sera had immunoglobulin G titres of 1:60 and were considered positive. The PCR technique in faeces for L. intracellularis DNA identified 7 horses as faecal shedders. Horses shedding the organism appeared healthy, indicating that subclinical infection of L. intracellularis occurred in the horses. CONCLUSION Seropositivity and detection of faecal shedding of L. intracellularis indicates the presence of the agent in the equine population in Minas Gerais. POTENTIAL RELEVANCE Results of this study should alert clinicians in countries where proliferative enteropthy in horses has not been reported to consider this disease as a possible cause of enteric disease.
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Affiliation(s)
- C V Guimarães-Ladeira
- Department of Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627 - Pampulha, PO Box 567, Belo Horizonte, MG 31.270-901, Brazil
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Microarray analysis of differential expression of cell cycle and cell differentiation genes in cells infected with Lawsonia intracellularis. Vet J 2009; 184:340-5. [PMID: 19362500 DOI: 10.1016/j.tvjl.2009.03.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2008] [Revised: 03/05/2009] [Accepted: 03/06/2009] [Indexed: 01/18/2023]
Abstract
Infection of intestinal crypt epithelial cells by the obligate intracellular bacterium Lawsonia intracellularis is directly linked to marked proliferation of the infected enterocytes within 3-5days post-infection. The virulence factor for this unique host cell-proliferative response is not known, but is considered to involve altered crypt cell cycle or differentiation events. McCoy mouse fibroblast cells were infected with L. intracellularis, and then harvested for expressed mRNA at daily time points, with matching non-infected control cell cultures. Mouse DNA microarray (>44,000 transcript targets) analysis of cDNA derived from matching mRNA samples showed over 40 identifiable genes with at least 4-fold changes between days 0 and 3 after infection with L. intracellularis. These included altered transcription of typical host cell 'alarm' response genes, such as interferon-related response genes Isgf3g and Igtp, known to be associated with invading microbial agents. Altered transcription of several genes in these cells known to be active in regulation of the cell cycle or cell differentiation genes, including usp18, Hr, Elavl2 and Slfn2, were also detected. The altered transcription of several of these genes via RT-PCR analysis was confirmed. The microarray-detected altered transcription of cell cycle and cell differentiation genes is of possible interest for links to Lawsonia-related disturbances in epithelial cell differentiation within the intestinal crypt, but this would need to be confirmed in intestinal epithelial cell studies.
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Murakata K, Sato A, Yoshiya M, Kim S, Watarai M, Omata Y, Furuoka H. Infection of different strains of mice with Lawsonia intracellularis derived from rabbit or porcine proliferative enteropathy. J Comp Pathol 2008; 139:8-15. [PMID: 18479698 DOI: 10.1016/j.jcpa.2008.03.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2007] [Accepted: 03/05/2008] [Indexed: 12/12/2022]
Abstract
This report describes intestinal lesions in five strains of mice infected orally with Lawsonia intracellularis-infected tissue homogenates from rabbits or pigs (RLI and PLI). BALB/cA, C3H/HeJ, C57BL/6J and ICR mice were susceptible to infection with RLI, whereas only C3H/HeJ, C57BL/6J and ICR strains were susceptible to PLI. In susceptible mice, crypt epithelial hyperplasia occurred in association with an inflammatory reaction, as in proliferative enteropathy (PE) in other species. The intestinal changes in the infected mice varied from mild to severe. Unlike rabbit or porcine PE, in which the changes are confined to the ileum, the lesions in mice were located in the caecum. Immunolabelling of L. intracellularis antigen was abundant in early infection when the epithelial hyperplasia was mild or absent. When the hyperplasia had become severe, however, immunolabelling was weak. For this reason, it is suggested that transitory infection of the epithelium induces epithelial hyperplasia. Genetic differences between mouse strains appeared to play an important role in the response to L. intracellularis infection. Moreover, the susceptibility of BALB/cA mice to RLI but not to PLI suggests that there are significant biological differences between L. intracellularis isolates from rabbit PE and porcine PE.
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Affiliation(s)
- K Murakata
- Department of Pathobiological Science, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Japan
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The microbiota of pigs influenced by diet texture and severity of Lawsonia intracellularis infection. Vet Microbiol 2008; 128:96-107. [DOI: 10.1016/j.vetmic.2007.09.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2007] [Revised: 09/05/2007] [Accepted: 09/11/2007] [Indexed: 11/23/2022]
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Meeusen ENT, Walker J, Peters A, Pastoret PP, Jungersen G. Current status of veterinary vaccines. Clin Microbiol Rev 2007; 20:489-510, table of contents. [PMID: 17630337 PMCID: PMC1932753 DOI: 10.1128/cmr.00005-07] [Citation(s) in RCA: 263] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The major goals of veterinary vaccines are to improve the health and welfare of companion animals, increase production of livestock in a cost-effective manner, and prevent animal-to-human transmission from both domestic animals and wildlife. These diverse aims have led to different approaches to the development of veterinary vaccines from crude but effective whole-pathogen preparations to molecularly defined subunit vaccines, genetically engineered organisms or chimeras, vectored antigen formulations, and naked DNA injections. The final successful outcome of vaccine research and development is the generation of a product that will be available in the marketplace or that will be used in the field to achieve desired outcomes. As detailed in this review, successful veterinary vaccines have been produced against viral, bacterial, protozoal, and multicellular pathogens, which in many ways have led the field in the application and adaptation of novel technologies. These veterinary vaccines have had, and continue to have, a major impact not only on animal health and production but also on human health through increasing safe food supplies and preventing animal-to-human transmission of infectious diseases. The continued interaction between animals and human researchers and health professionals will be of major importance for adapting new technologies, providing animal models of disease, and confronting new and emerging infectious diseases.
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Affiliation(s)
- Els N T Meeusen
- Animal Biotechnology Research Laboratories, Department of Physiology, Building 13f, Monash University, Clayton, Victoria 3800, Australia.
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Kroll JJ, Roof MB, Hoffman LJ, Dickson JS, Harris DLH. Proliferative enteropathy: a global enteric disease of pigs caused byLawsonia intracellularis. Anim Health Res Rev 2007; 6:173-97. [PMID: 16583781 DOI: 10.1079/ahr2005109] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
AbstractProliferative enteropathy (PE; ileitis) is a common intestinal disease affecting susceptible pigs raised under various management systems around the world. Major developments in the understanding of PE and its causative agent,Lawsonia intracellularis, have occurred that have led to advances in the detection of this disease and methods to control and prevent it. Diagnostic tools that have improved overall detection and early onset of PE in pigs include various serological and molecular-based assays. Histological tests such as immunohistochemistry continue to be the gold standard in confirmingLawsonia-specific lesions in pigspost mortem. Despite extreme difficulties in isolatingL. intracellularis, innovations in the cultivation and the development of pure culture challenge models, have opened doors to better characterization of the pathogenesis of PE throughin vivoandin vitro L. intracellularis–host interactions. Advancements in molecular research such as the genetic sequencing of the entireLawsoniagenome have provided ways to identify various immunogens, metabolic pathways and methods for understanding the epidemiology of this organism. The determinations of immunological responsiveness in pigs to virulent and attenuated isolates ofL. intracellularisand identification of various immunogens have led to progress in vaccine development.
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Affiliation(s)
- Jeremy J Kroll
- Department of Research and Development, Boehringer Ingelheim Vetmedica Inc., 2501 North Loop Drive, Ames, Iowa 50010, USA.
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Yeh JY, Kim TJ, Park SY, Song CS, Yoon YD, Kim SK, Lee JB, Choi IS. Isolation of Lawsonia intracellularis in Korea and reproduction of proliferative enteropathy in pigs and hamsters. J Vet Med Sci 2007; 68:499-501. [PMID: 16757895 DOI: 10.1292/jvms.68.499] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Lawsonia intracellularis (L. intracellularis) was isolated from a Korean pig suffering acute proliferative enteropathy. In vitro culture conditions of L. intracellularis were established in McCoy cells. Pigs and hamsters experimentally infected with the pure culture of L. intracellularis reproduced clinical signs and intestinal lesions of proliferative enteropathy. The presence of L. intracellularis in the intestinal lesions was confirmed by immunohistochemistry with L. intracellularis-specific monoclonal antibodies.
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Affiliation(s)
- Jung-Yong Yeh
- National Veterinary Research and Quarantine Service, Seoul, Korea
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Michalski CW, Di Mola FF, Kümmel K, Wendt M, Köninger JS, Giese T, Giese NA, Friess H. Human inflammatory bowel disease does not associate with Lawsonia intracellularis infection. BMC Microbiol 2006; 6:81. [PMID: 16984651 PMCID: PMC1590022 DOI: 10.1186/1471-2180-6-81] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2006] [Accepted: 09/19/2006] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND There is increasing evidence that bacterial infection of the intestinal mucosa may contribute to the pathogenesis of inflammatory bowel diseases (IBD). In pigs, an obligate intracellular bacterium, Lawsonia intracellularis (LI), was shown to cause proliferative enteropathy (PE) of which some forms display histological and clinical similarities to human IBD. Since LI-similar Desulfovibrio spp. may infect human cells, we hypothesized that LI might be associated with the development of human IBD. RESULTS In human intestinal tissue samples, PCR using LLG, 50SL27, LSA and strictly LI-specific 16SII primers, yielded either no amplicons or products with weak homology to human genomic sequences. Sequencing of these amplicons revealed no specificity for LI. However, amplification of DNA with less specific 16SI primers resulted in products bearing homology to certain Streptococcus species. These 16SI-amplified products were present in healthy and diseased specimens, without obvious prevalence. CONCLUSION LI is not associated with the pathogenesis of UC or CD. Whether an immunologic response to commensal bacteria such as streptococci may contribute to the chronic inflammatory condition in IBD, remained to be determined.
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Affiliation(s)
- Christoph W Michalski
- Department of General Surgery, University of Heidelberg, Im Neuenheimer Feld 110, D-69210 Heidelberg, Germany
| | - Fabio Francesco Di Mola
- Department of General Surgery, University of Heidelberg, Im Neuenheimer Feld 110, D-69210 Heidelberg, Germany
| | - Klaus Kümmel
- Department of General Surgery, University of Heidelberg, Im Neuenheimer Feld 110, D-69210 Heidelberg, Germany
| | - Michael Wendt
- Clinic for Pigs, Small Ruminants, Forensic Medicine and Ambulatory Service, University of Veterinary Medicine, Bünteweg 2, D-30559 Hannover, Germany
| | - Jörg S Köninger
- Department of General Surgery, University of Heidelberg, Im Neuenheimer Feld 110, D-69210 Heidelberg, Germany
| | - Thomas Giese
- Institute of Immunology, University of Heidelberg, Im Neuenheimer Feld 305, D-69120 Heidelberg, Germany
| | - Nathalia A Giese
- Department of General Surgery, University of Heidelberg, Im Neuenheimer Feld 110, D-69210 Heidelberg, Germany
| | - Helmut Friess
- Department of General Surgery, University of Heidelberg, Im Neuenheimer Feld 110, D-69210 Heidelberg, Germany
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Whitney MH, Shurson GC, Guedes RC. Effect of dietary inclusion of distillers dried grains with solubles, soybean hulls, or a polyclonal antibody product on the ability of growing pigs to resist a Lawsonia intracellularis challenge. J Anim Sci 2006; 84:1880-9. [PMID: 16775072 DOI: 10.2527/jas.2004-578] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
An experiment was conducted to determine if dietary inclusion of distillers dried grains with solubles (DDGS), soybean hulls, or soybean hulls sprayed with an egg-based, polyclonal antibody product would reduce the incidence or severity of infection, or both, in growing pigs after a Lawsonia intracellularis challenge. One hundred 17-d-old weaned pigs were blocked by sex, ancestry, and BW, and randomly allotted to 1 of 5 treatment groups: negative control, unchallenged, corn-soy diet; positive control, challenged, corn-soy diet; 20% DDGS diet (D), challenged; 5% soybean hulls diet (SH), challenged; and SH sprayed with a polyclonal antibody product diet, challenged. Challenged pigs were orally inoculated with 6.4 x 10(8) L. intracellularis organisms after a 4-wk prechallenge feeding period. On d 21 postchallenge, pigs were euthanized, lesions of intestinal mucosa were evaluated, and ileal tissue samples were analyzed by immunohistochemistry to determine the presence and proliferation rate of L. intracellularis. Challenging pigs with L. intracellularis reduced growth rate, feed intake, and efficiency of gain (P < 0.02) and increased the proportion of internal organ weights relative to BW (P < 0.01). Dietary treatment did not affect growth performance pre- or postchallenge (P > 0.10). Heart, empty stomach, and liver weights were similar among dietary treatments (P > 0.10). Weight of the large intestine as a percentage of BW was increased in D and SH pigs compared with positive control pigs (P < 0.05). Lesion length, prevalence, and severity, and fecal shedding of L. intracellularis were primarily unaffected by dietary treatment (P > 0.10), although ileal lesion length and severity observed tended to be greater in the SH sprayed with polyclonal antibody product diet vs. the D pigs (P < 0.10). Results from a previous study indicated that diet composition may affect length, severity, and prevalence of lesions caused by L. intracellularis in growing pigs subjected to a moderate challenge. However, beneficial results were not observed by feeding the dietary treatments used in this study.
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Affiliation(s)
- M H Whitney
- Department of Animal Science, University of Minnesota, St. Paul 55108, USA.
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Abstract
In this study we examined the proliferative enteropathy, caused by the obligate intracellular bacterium Lawsonia intracellularis, in colon of naturally infected pigs, using immunohistochemistry, in situ hybridisation and scanning confocal laser microscopy. When 396 pigs submitted for routine laboratory examination were investigated, large intestinal gross lesions were seen in 93, including 74 cases of L. intracellularis colitis (proliferative enteropathy). Fifty-one pigs without recorded colonic gross lesions revealed L. intracellularis colitis microscopically. In four cases, L. intracellularis was only revealed in colon. Fifty-seven pigs were positive for L. intracellularis in the small intestines only. Thus, the overall prevalence of colonic infection in L. intracellularis-positive animals was as high as 69% (125 out of 182). In comparison, the large intestinal pathogens Brachyspira hyodysenteriae and Salmonella enterica were only isolated from 5 and 4 of the 93 cases, respectively. Morphologically, an unforeseen severe involvement of the subepithelial mucosa with multiple L. intracellularis found free and within large macrophages was observed in areas with acute infection. The distribution of whole L. intracellularis organisms was confirmed by in situ hybridisation and scanning confocal laser microscopy. The significance and possible role of subepithelial infection in the proliferative enteropathy is discussed. In conclusion, the study shows that L. intracellularis is a prevalent cause of naturally acquired colitis in pigs.
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Affiliation(s)
- T K Jensen
- Danish Veterinary Institute, Copenhagen, Denmark
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Gustafsdottir SM, Nordengrahn A, Fredriksson S, Wallgren P, Rivera E, Schallmeiner E, Merza M, Landegren U. Detection of individual microbial pathogens by proximity ligation. Clin Chem 2006; 52:1152-60. [PMID: 16723682 DOI: 10.1373/clinchem.2005.065847] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Nucleic acid amplification allows the detection of single infectious agents. Protein-based assays, although they provide information on ongoing infections, have substantially less detection sensitivity. METHODS We used proximity ligation reactions to detect proteins on bacteria and virus particles via nucleic acid amplification. Antibodies recognizing viral or bacterial surface proteins were equipped with DNA strands that could be joined by ligation when several antibodies were bound in proximity to surface proteins of individual infectious agents. RESULTS Detection sensitivities similar to those of nucleic acid-based detection reactions were achieved directly in infected samples for a parvovirus and an intracellular bacterium. CONCLUSIONS This method enables detection of ligated DNA strands with good sensitivity by real-time PCR and could be of value for early diagnosis of infectious disease and in biodefense.
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Affiliation(s)
- Sigrun M Gustafsdottir
- The Beijer Laboratory, Department of Genetics and Pathology, Rudbeck Laboratory, Uppsala, Sweden
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Kroll JJ, Eichmeyer MA, Schaeffer ML, McOrist S, Harris DL, Roof MB. Lipopolysaccharide-based enzyme-linked immunosorbent assay for experimental use in detection of antibodies to Lawsonia intracellularis in pigs. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2006; 12:693-9. [PMID: 15939742 PMCID: PMC1151981 DOI: 10.1128/cdli.12.6.693-699.2005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
An enzyme-linked immunosorbent assay (ELISA) for Lawsonia intracellularis was developed and compared with a whole-cell antigen-based immunofluorescence antibody test (IFAT). The antigen-containing lipopolysaccharide (LPS) was derived from Percoll gradient purified cultures of L. intracellularis by using a modification of the Westphal hot phenol procedure. The antigen was bound directly to polystyrene 96-well microtiter plates, and the assay was performed in an indirect ELISA format. Specificity and sensitivity values based on 80 known positive and 80 known negative serum samples from controlled experimental trials were 93.7% and 88.7%, respectively. Serological results from a controlled L. intracellularis challenge exposure study confirmed the high specificity and sensitivity of this assay (100% and 99.5%, respectively). Comparisons between the LPS ELISA and the IFAT in detecting anti-Lawsonia antibodies in this controlled study revealed significantly more LPS ELISA-positive pigs than IFAT-positive pigs on days 21, 28, 35, and 42 (P = 0.003, 0.030, 0.002, and 0.006, respectively). This indirect ELISA (LPS ELISA) test is an improved method of detecting antibodies in pigs soon after exposure to L. intracellularis, regardless of isolate type (vaccine or wild type) in experimental studies. The LPS ELISA may be used as a tool to support future research trials on vaccine efficacy and to further understand the immune response induced by L. intracellularis.
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Affiliation(s)
- J J Kroll
- Department of Research and Development, Boehringer Ingelheim Vetmedica Inc., 2501 North Loop Drive, Ames, Iowa 50010, USA.
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McOrist S, Gebhart CJ, Bosworth BT. Evaluation of porcine ileum models of enterocyte infection by Lawsonia intracellularis. CANADIAN JOURNAL OF VETERINARY RESEARCH = REVUE CANADIENNE DE RECHERCHE VETERINAIRE 2006; 70:155-9. [PMID: 16639950 PMCID: PMC1410719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The early interaction of Lawsonia intracellularis with host cells was examined with the use of porcine ileum models. Two conventional swine were anesthetized, and ligated ileum loops were prepared during abdominal surgery. The loops were inoculated with 108 L. intracellularis or saline. After 60 min, samples of each loop were processed for routine histologic and electron microscopic study. Histologic and ultrathin sections of all the loops appeared normal, with no apposition of bacteria and host cells or bacterial entry events in any loop. Portions of ileum from a single gnotobiotic piglet were introduced as xenografts into the subcutis of each flank of 5 weaned mice with severe combined immunodeficiency disease. After 4 wk, 108 L. intracellularis were inoculated into each of 4 viable xenografts with a sterile needle; the other 3 viable xenografts received saline. Histologic and ultrathin sections of all the xenografts 3 wk after inoculation showed relatively normal porcine intestinal architecture, with normal crypts, crypt cell differentiation, and low villous structures; the xenografts treated with the bacteria also showed intracytoplasmic L. intracellularis within crypt and villous epithelial cells. Thus, entry of L. intracellularis into target epithelial cells and multiplication may not be sufficient alone to directly cause cell proliferation. A proliferative response may require active division of crypt cells and differentiation in conjunction with L. intracellularis growth.
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Affiliation(s)
- Steven McOrist
- Tufts University School of Veterinary Medicine, 200 Westboro Road, North Grafton, Massachusetts 01536, USA.
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Bernbom N, Licht TR, Saadbye P, Vogensen FK, Nørrung B. Lactobacillus plantarum inhibits growth of Listeria monocytogenes in an in vitro continuous flow gut model, but promotes invasion of L. monocytogenes in the gut of gnotobiotic rats. Int J Food Microbiol 2006; 108:10-4. [PMID: 16376449 DOI: 10.1016/j.ijfoodmicro.2005.10.021] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2005] [Revised: 09/19/2005] [Accepted: 10/12/2005] [Indexed: 11/22/2022]
Abstract
The ability of the pediocin AcH producing Lactobacillus plantarum DDEN 11007 and its non-producing plasmid-cured isogenic variant, DDEN 12305 to prevent the persistence and growth of Listeria monocytogenes EP2 in two gastrointestinal (GI) tract models was examined. In vitro studies conducted in a two-stage continuous flow system showed that L. plantarum DDEN 11007 inhibited L. monocytogenes EP2 under these conditions, while less effect was seen of the non-bacteriocin producing variant. The inhibitory effect was more pronounced at pH 5 than at pH 7. No effect on persistence of L. monocytogenes in the GI tract was seen in gnotobiotic rats colonized with either the pediocin AcH producing or the non-bacteriocin producing variant of L. plantarum when compared to rats inoculated with L. monocytogenes EP2 alone. Surprisingly, inoculation of the gnotobiotic animals with either of the L. plantarum strains prior to inoculation with L. monocytogenes EP2 resulted in increased occurrence of L. monocytogenes in liver and spleen when compared to the animals inoculated with L. monocytogenes EP2 alone. Our results indicate that the presence of L. plantarum in the gut of gnotobiotes facilitates L. monocytogenes invasion by an unknown mechanism. This observation is however not necessarily specifically related to L. plantarum, and should not be interpreted as the expected effect in animals carrying a conventional intestinal microflora.
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Affiliation(s)
- Nete Bernbom
- Department of Microbiological Food Safety, Danish Institute for Food and Veterinary Research, Mørkhøj Bygade 19, DK-2860 Søborg, Denmark
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Jensen TK, Vigre H, Sørensen V, Møller K. Naturally acquired Lawsonia intracellularis infection in pigs studied from weaning to slaughter by indirect immunofluorescence antibody test and polymerase chain reaction on faeces. Res Vet Sci 2005; 79:93-8. [PMID: 15885725 DOI: 10.1016/j.rvsc.2004.08.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2003] [Revised: 08/02/2004] [Accepted: 08/05/2004] [Indexed: 11/17/2022]
Abstract
The course of naturally acquired Lawsonia intracellularis infection was studied in 41 pigs by testing blood and faeces samples collected four to seven times from before weaning to slaughter 5 months old. At slaughter, a sample of ileum was taken for histopathology. In the first sampling when the pigs were 2-4 weeks old maternally derived IgG against L. intracellularis was demonstrated by immunofluorescence antibody test in nine pigs whereas the bacterium was detected by PCR in faeces from six pigs. The maternally derived antibodies did not prevent pigs from becoming infected as seven pigs later on shed and/or were seropositive for L. intracellularis. The lowest prevalence of L. intracellularis was observed in 6-13 weeks old pigs and it seemed as though L. intracellularis in early infected pigs only activates a minor antibody response. At slaughter 66% of the pigs were found positive by immunofluorescence antibody test compared to 24% by immunohistochemistry on ileal samples. Thus, applied at the time of slaughter the antibody test appeared to be a highly sensitive ante-mortem diagnostic tool for identifying L. intracellularis exposed pigs with or without current proliferative enteropathy.
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Affiliation(s)
- T K Jensen
- Danish Institute for Food and Veterinary Research, Bülowsvej 27, DK-1790 Copenhagen V, Denmark.
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Class M, Bilkei G. Seroprevalence of antibodies against Lawsonia intracellularis among growing pigs raised in indoor versus outdoor units. J Am Vet Med Assoc 2004; 225:1905-7. [PMID: 15643842 DOI: 10.2460/javma.2004.225.1905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine change over time in sero-prevalence of antibodies against Lawsonia intracellularis among growing-finishing pigs housed in indoor versus outdoor facilities. DESIGN Serologic survey. ANIMALS 93 pigs born to seropositive gilts and raised in indoor (n = 49) or outdoor (44) growing-finishing facilities. PROCEDURE Blood samples were collected from the pigs 2, 6, 10, 14, 18, 22, and 26 weeks after birth and tested for antibodies against L intracellularis with an indirect immunofluorescence assay. RESULTS None of the pigs were seropositive 2 or 6 weeks after birth. Ten weeks after birth, 74% and 76% of pigs in indoor and outdoor growing-finishing facilities were seropositive, respectively, whereas 14 weeks after birth, the percentage of pigs in indoor growing-finishing facilities that were seropositive was substantially higher than the percentage of pigs in outdoor facilities that were. From 18 weeks after birth to the end of the study, none of the pigs in outdoor growing-finishing facilities were seropositive, whereas low percentages of pigs in indoor facilities were seropositive 18, 22, and 26 weeks after birth. CONCLUSIONS AND CLINICAL RELEVANCE Results suggest that seroprevalence of antibodies against L intracellularis decreases faster among growing-finishing pigs housed in outdoor facilities than among growing-finishing pigs housed in indoor facilities.
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Affiliation(s)
- Mike Class
- Bilkei Consulting, Raubbühlstrasse, 8600 Dübendorf, Switzerland
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van der Heijden HMJF, Bakker J, Elbers ARW, Vos JH, Weyns A, de Smet M, McOrist S. Prevalence of exposure and infection of Lawsonia intracellularis among slaughter-age pigs. Res Vet Sci 2004; 77:197-202. [PMID: 15276770 DOI: 10.1016/j.rvsc.2004.04.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/09/2004] [Indexed: 11/22/2022]
Abstract
The extent of clinical or subclinical infection associated with Lawsonia intracellularis within Dutch pig herds was uncertain. A case-control study of slaughter age pigs was used to study natural infection within Dutch herds and to compare diagnostic methods. From six case herds where clinical disease had been identified recently, and six disease-free herds, 40 pigs of slaughter-age were examined postmortem. The diagnostic methods used were: serology, gross examination, Haematoxylin and Eosin stain (HE), Warthin-Starry silver stain, Lawsonia-specific indirect immunoperoxidase of the ileum, and PCR of ileum mucosa and colon contents. There were 59% seropositive pigs in case herds and 26% seropositive pigs in control herds. Using immunohistochemistry, 57% of case herds and 46% of control herds were bacteria positive in the ileum mucosa. It was concluded that a majority of Dutch herds contain L. intracellularis infected finisher pigs. In some herds this is associated with clinical outbreaks of acute haemorrhagic enteropathy but in other herds no clinical disease is apparent. Many seropositive pigs in herds without clinical disease had evidence of Lawsonia antigen in sites other than the apical cytoplasm of proliferating epithelial cells, particularly the supranuclear region. It was uncertain whether to classify these pigs as having "recovered" from an infection or whether they have a sub-clinical or chronic form of the disease. We concluded that PCR examination of faeces and serology probably provide more specific results than gross examinations at slaughter, and that a monoclonal antibody-based examination of ileum mucosa should be the accepted screening method for this infection.
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Boesen HT, Jensen TK, Schmidt AS, Jensen BB, Jensen SM, Møller K. The influence of diet on Lawsonia intracellularis colonization in pigs upon experimental challenge. Vet Microbiol 2004; 103:35-45. [PMID: 15381264 DOI: 10.1016/j.vetmic.2004.06.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2003] [Revised: 05/17/2004] [Accepted: 06/14/2004] [Indexed: 10/26/2022]
Abstract
The objective of this investigation was to study if different feeding strategies influence experimental infections of pigs with Lawsonia intracellularis, the causative agent of proliferative enteropathy. In three sequential trials, a total of 144 weaned pigs were fed five different diets all made from a standard diet based on wheat and barley as carbohydrate source and soybean as protein source. The five diets were: a standard diet (fine ground and pelleted), the standard diet fed as fermented liquid feed, the standard diet added 1.8% formic acid, the standard diet added 2.4% lactic acid and a diet similar to the standard diet (made from the same ingredients), but fed coarse ground. Twenty-four pigs on each diet were orally inoculated with L. intracellularis and growth performance and faecal excretion of bacteria were monitored. Twenty-four pigs fed the standard diet were included as not experimentally infected controls. Pigs in the first two trials were sacrificed 4 weeks post-inoculation, whereas animals in the third trial were sacrificed after 5 weeks. Pigs in all experimentally infected groups excreted L. intracellularis. The fermented liquid diet delayed the excretion of L. intracellularis and furthermore, pigs fed the standard diet supplemented with lactic acid had limited pathological lesions when the intestines were examined 4 weeks after inoculation. The growth performance was reduced in pigs experimentally challenged with L. intracellularis, however the prevalence and severity of diarrhea was limited.
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Affiliation(s)
- Henriette T Boesen
- Danish Institute for Food and Veterinary Research, Bülowsvej 27, DK-1790 Copenhagen V, Denmark.
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44
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Kroll JJ, Roof MB, McOrist S. Evaluation of protective immunity in pigs following oral administration of an avirulent live vaccine of Lawsonia intracellularis. Am J Vet Res 2004; 65:559-65. [PMID: 15141873 DOI: 10.2460/ajvr.2004.65.559] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate the efficacy of an orally administered avirulent live vaccine to protect pigs against challenge exposure with virulent Lawsonia intracellularis. ANIMALS 108 weaned 3-week-old pigs (35 in experiment 1 and 73 in experiment 2). PROCEDURE 2 experiments were conducted. On day 0, vaccinates were orally administered vaccine via drench or in drinking water, whereas challenge-control pigs were administered cultured medium. On day 21, pigs were challenge exposed with a virulent heterologous isolate of L. intracellularis. Clinical observations, weights, seroconversion, and fecal excretion of L. intracellularis were measured until day 42. At study termination, pigs were euthanatized and examined for L. intracellularis-specific lesion development of the ileum and colon. RESULTS Pigs receiving a single dose of vaccine were protected when challenge exposed with virulent L. intracellularis (at least 10(77) TCID50/dose). In experiment 1, vaccinates had significantly less fecal excretion (47% and 40% for days 35 and 42, respectively), compared with challenge-control pigs. In experiment 2, vaccinates had significantly less fecal excretion (50% and 58% for days 35 and 42, respectively), compared with challenge-control pigs. Significant reductions in lesion development were evident in the ileum of vaccinated pigs (70% and 56% at day 42 for experiments 1 and 2, respectively), compared with challenge-control pigs. CONCLUSIONS AND CLINICAL RELEVANCE Oral administration by drench or via drinking water of an avirulent live vaccine against L. intracellularis resulted in substantial protection against proliferative enteropathy among vaccinates and offers a better way to reduce stress of pigs during vaccine administration.
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Affiliation(s)
- Jeremy J Kroll
- Department of Biological Research and Development, Boehringer Ingelheim Vetmedica Inc, 2501 N Loop Dr, Ames, IA 50010, USA
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Ott SJ, Musfeldt M, Wenderoth DF, Hampe J, Brant O, Fölsch UR, Timmis KN, Schreiber S. Reduction in diversity of the colonic mucosa associated bacterial microflora in patients with active inflammatory bowel disease. Gut 2004; 53:685-93. [PMID: 15082587 PMCID: PMC1774050 DOI: 10.1136/gut.2003.025403] [Citation(s) in RCA: 884] [Impact Index Per Article: 44.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND AIMS The intestinal bacterial microflora plays an important role in the aetiology of inflammatory bowel disease (IBD). As most of the colonic bacteria cannot be identified by culture techniques, genomic technology can be used for analysis of the composition of the microflora. PATIENTS AND METHODS The mucosa associated colonic microflora of 57 patients with active inflammatory bowel disease and 46 controls was investigated using 16S rDNA based single strand conformation polymorphism (SSCP) fingerprint, cloning experiments, and real time polymerase chain reaction (PCR). RESULTS Full length sequencing of 1019 clones from 16S rDNA libraries (n = 3) revealed an overall bacterial diversity of 83 non-redundant sequences-among them, only 49 known bacterial species. Molecular epidemiology of the composition of the colonic microflora was investigated by SSCP. Diversity of the microflora in Crohn's disease was reduced to 50% compared with controls (21.7 v 50.4; p<0.0001) and to 30% in ulcerative colitis (17.2 v 50.4; p<0.0001). The reduction in diversity in inflammatory bowel disease was due to loss of normal anaerobic bacteria such as Bacteroides species, Eubacterium species, and Lactobacillus species, as revealed by direct sequencing of variable bands and confirmed by real time PCR. Bacterial diversity in the Crohn's group showed no association with CARD15/NOD2 status. CONCLUSIONS Mucosal inflammation in inflammatory bowel disease is associated with loss of normal anaerobic bacteria. This effect is independent of NOD2/CARD15 status of patients.
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Affiliation(s)
- S J Ott
- Department of General Internal Medicine, University Hospital Schleswig-Holstein, Campus Kiel, Germany
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Guedes RMC, Winkelman NL, Gebhart CJ. Relationship between the severity of porcine proliferative enteropathy and the infectious dose of Lawsonia intracellularis. Vet Rec 2003; 153:432-3. [PMID: 14582733 DOI: 10.1136/vr.153.14.432] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- R M C Guedes
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Minnesota, St Paul, MN 55108, USA
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47
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Barna P, Bilkei G. Effect of gilt seropositivity to Lawsonia intracellularis (LI) on their offspring’s seropositivity to LI and on diarrhoea after a pure-culture challenge. Prev Vet Med 2003; 61:71-8. [PMID: 14516718 DOI: 10.1016/s0167-5877(03)00159-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
This study was done in a large Croatian pig-production unit. Blood samples from late-pregnancy gilts were tested by an indirect immunofluorescence-antibody (IFA) serum assay for Lawsonia intracellularis (LI). Ten IFA-positive and 10 IFA-negative gilts were selected. The 2-week-old piglets (97 from positive gilts, and 98 from negative gilts) were inoculated intragastrically with pure culture of LI. All pigs were tested until slaughter for seroprevalence of LI. Blood samples were collected at 5, 8, 11, 14, 17, 20, 23 and 26 weeks of age. Seropositivity in offspring of IFA-negative gilts was highest at age 5 weeks (84%) and declined gradually from week 11 to only 10% at week 26. At the same time, the offspring of IFA-positive gilts showed lower and faster-decaying seroprevalence: only 32% at week 5 and 0% starting at week 17. There was no difference in the pen-days of diarrhoea between the offspring of LI-seropositive and -seronegative gilts.
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Affiliation(s)
- P Barna
- Bilkei Consulting, Raubbühlstrasse 4, CH-8600 Dübendorf, Switzerland
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48
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MacIntyre N, Smith DGE, Shaw DJ, Thomson JR, Rhind SM. Immunopathogenesis of experimentally induced proliferative enteropathy in pigs. Vet Pathol 2003; 40:421-32. [PMID: 12824514 DOI: 10.1354/vp.40-4-421] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
To characterize the immune response associated with Lawsonia intracellularis infection, twenty-eight, 7-week-old pigs were dosed orally with a pure culture of L. intracellularis. Animals were killed 3, 7, 14, 21, 28, 35, and 42 days postinfection. Light microscopic studies were undertaken to immunophenotype the immunologic response using specific antibodies to T-cell subsets (CD3, CD4, and CD8), B cells, major histocompatibility complex class II, cadherin, and macrophages over the course of time. The results indicate that there is a direct association between the presence of L. intracellularis and reduced T-cell and B-cell numbers. For the first time, this provides evidence of the presence of an immunosuppressive mechanism operating in this disease. Furthermore, macrophage marker studies indicated that macrophages may play a more complex and significant role in the disease process than has been previously reported, with activated macrophages accumulating in infected hyperplastic crypts.
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Affiliation(s)
- N MacIntyre
- Department of Veterinary Pathology, Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Easter Bush Veterinary Centre, Midlothian EH25 9RG, Scotland, UK
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49
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Abstract
In 11 'farrow-to-finish' outdoor or indoor production units, blood samples from late pregnant gilts were tested by indirect immunofluorescence antibody (IFA) serum assay for Lawsonia intracellularis. The offspring of positively tested gilts were tested at 2, 7, 12, 17, 22 and 27 weeks of age for seroprevalence of Lawsonia intracellularis. All offspring of IFA positive gilts were seronegative at 2 and 7 weeks of age. At 12 weeks of age 81.0% of indoor and 51.0% of outdoor pigs were tested positive. While at 17 weeks of age 82.5% of indoor-raised pigs showed seropositivity, in outdoor units the seropositivity declined to 31.3%. At weeks 22 and 27 indoor-raised pigs still showed marked seropositivity (17.7% and 11.5%) but their outdoor-raised counterparts revealed declining values (7.4% and 0%).
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Affiliation(s)
- B Hagen
- Bilkei Consulting, Raubbühlstrasse 4, CH-8600 Dübendorf, Switzerland
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50
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Guedes RMC, Gebhart CJ. Comparison of intestinal mucosa homogenate and pure culture of the homologous Lawsonia intracellularis isolate in reproducing proliferative enteropathy in swine. Vet Microbiol 2003; 93:159-66. [PMID: 12637004 DOI: 10.1016/s0378-1135(03)00013-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Little information is available on reproduction of proliferative enteropathy (PE) using a virulent pure culture of Lawsonia intracellularis. Reproduction of the disease using PE-diseased mucosa homogenates, however, is well-characterized. The aims of this study were to evaluate and compare clinical signs, growth performance and the severity of lesions in pigs inoculated with intestinal mucosa homogenate or pure culture of the homologous L. intracellularis isolate. Five-week-old pigs were inoculated with pure culture of L. intracellularis (isolate PHE/MN1-00; n=10), PE-diseased mucosa (n=10), or control media (n=4). The L. intracellularis isolate PHE/MN1-00 used in the pure culture inoculum was extracted from a fragment of the same intestine used to prepare the mucosa homogenate. Clinical signs and growth performance were evaluated throughout the study. Fecal shedding was evaluated in all animals weekly during the experiment. All animals were euthanized 22 days post-inoculation, the intestines were examined grossly and histologically. Results showed that both the infection procedures reproduced clinical disease, macroscopic and histologic lesions typical of PE. Fecal shedding was detected in animals in both challenge groups. In conclusion, the L. intracellularis isolate PHE/MN1-00 reproduces typical clinical signs and lesions of PE similar to the homologous infection with an intestinal mucosa homogenate.
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Affiliation(s)
- Roberto M C Guedes
- Department of Veterinary PathoBiology, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA.
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