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Serafini Poeta Silva AP, Mugabi R, Rotolo ML, Krantz S, Hu D, Robbins R, Hemker D, Diaz A, Tucker AW, Main R, Cano JP, Harms P, Wang C, Clavijo MJ. Effect of pooled tracheal sample testing on the probability of Mycoplasma hyopneumoniae detection. Sci Rep 2024; 14:10226. [PMID: 38702379 PMCID: PMC11068755 DOI: 10.1038/s41598-024-60377-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 04/22/2024] [Indexed: 05/06/2024] Open
Abstract
Tracheal pooling for Mycoplasma hyopneumoniae (M. hyopneumoniae) DNA detection allows for decreased diagnostic cost, one of the main constraints in surveillance programs. The objectives of this study were to estimate the sensitivity of pooled-sample testing for the detection of M. hyopneumoniae in tracheal samples and to develop probability of M. hyopneumoniae detection estimates for tracheal samples pooled by 3, 5, and 10. A total of 48 M. hyopneumoniae PCR-positive field samples were pooled 3-, 5-, and 10-times using field M. hyopneumoniae DNA-negative samples and tested in triplicate. The sensitivity was estimated at 0.96 (95% credible interval [Cred. Int.]: 0.93, 0.98) for pools of 3, 0.95 (95% Cred. Int: 0.92, 0.98) for pools of 5, and 0.93 (95% Cred. Int.: 0.89, 0.96) for pools of 10. All pool sizes resulted in PCR-positive if the individual tracheal sample Ct value was < 33. Additionally, there was no significant decrease in the probability of detecting at least one M. hyopneumoniae-infected pig given any pool size (3, 5, or 10) of tracheal swabs. Furthermore, this manuscript applies the probability of detection estimates to various real-life diagnostic testing scenarios. Combining increased total animals sampled with pooling can be a cost-effective tool to maximize the performance of M. hyopneumoniae surveillance programs.
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Affiliation(s)
| | - Robert Mugabi
- Veterinary Diagnostic and Population Animal Medicine, Iowa State University, Ames, IA, USA
| | | | | | - Dapeng Hu
- College of Liberal Arts and Sciences, Iowa State University, Ames, IA, USA
| | | | | | | | | | - Rodger Main
- Veterinary Diagnostic and Population Animal Medicine, Iowa State University, Ames, IA, USA
| | | | | | - Chong Wang
- Veterinary Diagnostic and Population Animal Medicine, Iowa State University, Ames, IA, USA
- College of Liberal Arts and Sciences, Iowa State University, Ames, IA, USA
| | - Maria Jose Clavijo
- Veterinary Diagnostic and Population Animal Medicine, Iowa State University, Ames, IA, USA.
- PIC®, Hendersonville, TN, USA.
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Lisgara M, Poulaki K, Kalogeropoulos L, Skampardonis V, Katsafadou AI. Frequency and severity of enzootic pneumonia-like lesions in Greek swine herds and their association with different vaccination protocols against Mycoplasma hyopneumoniae. JOURNAL OF APPLIED ANIMAL RESEARCH 2022. [DOI: 10.1080/09712119.2022.2110499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Affiliation(s)
| | | | | | - Vassilis Skampardonis
- Department of Epidemiology, Biostatistics and Animal Health Economics, Faculty of Veterinary Medicine, University of Thessaly, Karditsa, Greece
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Garcia-Morante B, Maes D, Sibila M, Betlach AM, Sponheim A, Canturri A, Pieters M. Improving Mycoplasma hyopneumoniae diagnostic capabilities by harnessing the infection dynamics. Vet J 2022; 288:105877. [PMID: 35901923 DOI: 10.1016/j.tvjl.2022.105877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 07/15/2022] [Accepted: 07/23/2022] [Indexed: 11/17/2022]
Abstract
Mycoplasma hyopneumoniae remains one of the most problematic bacterial pathogens for pig production. Despite an abundance of observational and laboratory testing capabilities for this organism, diagnostic interpretation of test results can be challenging and ambiguous. This is partly explained by the chronic nature of M. hyopneumoniae infection and its tropism for lower respiratory tract epithelium, which affects diagnostic sensitivities associated with sampling location and stage of infection. A thorough knowledge of the available tools for routine M. hyopneumoniae diagnostic testing, together with a detailed understanding of infection dynamics, are essential for optimizing sampling strategies and providing confidence in the diagnostic process. This study reviewed known information on sampling and diagnostic tools for M. hyopneumoniae and summarized literature reports of the dynamics of key infection outcomes, including clinical signs, lung lesions, pathogen detection, and humoral immune responses. Such knowledge could facilitate better understanding of the performance of different diagnostic approaches at various stages of infection.
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Affiliation(s)
- Beatriz Garcia-Morante
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, 1365 Gortner Ave, St. Paul, MN 55108, USA; IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Dominiek Maes
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Unit Porcine Health Management, Ghent University, Salisburylaan, 133 B-9820 Merelbeke, Belgium
| | - Marina Sibila
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Alyssa M Betlach
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, 1365 Gortner Ave, St. Paul, MN 55108, USA; Swine Vet Center, 1608 S Minnesota Ave, St. Peter, MN 56082, USA
| | - Amanda Sponheim
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, 1365 Gortner Ave, St. Paul, MN 55108, USA; Boehringer Ingelheim Animal Health USA Inc., 3239 Satellite Blvd NW, Duluth, GA 30096, USA
| | - Albert Canturri
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, 1365 Gortner Ave, St. Paul, MN 55108, USA
| | - Maria Pieters
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, 1365 Gortner Ave, St. Paul, MN 55108, USA; Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Minnesota, 1333 Gortner Ave, St Paul, 55108 MN, USA; Swine Disease Eradication Center, College of Veterinary Medicine, University of Minnesota, 1988 Fitch Ave, St. Paul, MN 55108, USA.
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Niemi JK, Edwards SA, Papanastasiou DK, Piette D, Stygar AH, Wallenbeck A, Valros A. Cost-Effectiveness Analysis of Seven Measures to Reduce Tail Biting Lesions in Fattening Pigs. Front Vet Sci 2021; 8:682330. [PMID: 34557537 PMCID: PMC8452948 DOI: 10.3389/fvets.2021.682330] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 08/12/2021] [Indexed: 11/23/2022] Open
Abstract
Tail biting is an important animal welfare issue in the pig sector. Studies have identified various risk factors which can lead to biting incidents and proposed mitigation measures. This study focused on the following seven key measures which have been identified to affect the risk of tail biting lesions: improvements in straw provision, housing ventilation, genetics, stocking density, herd health, provision of point-source enrichment objects, and adoption of early warning systems. The aim of this study was to examine whether these selected measures to reduce the risk of tail biting lesions in pig fattening are cost-effective. The problem was analyzed by first summarizing the most prospective interventions, their costs and expected impacts on the prevalence of tail biting lesions, second, by using a stochastic bio-economic model to simulate the financial return per pig space unit and per pig at different levels of prevalence of tail biting lesions, and third by looking at how large a reduction in tail biting lesions would be needed at different levels of initial prevalence of lesions to cover the costs of interventions. Tail biting lesions of a severity which would require an action (medication, hospitalization of the pig or other care, or taking preventive measures) by the pig producer were considered in the model. The results provide guidance on the expected benefits and costs of the studied interventions. According to the results, if the average prevalence of tail biting lesions is at a level of 10%, the costs of this damaging behavior can be as high as €2.3 per slaughtered pig (~1.6% of carcass value). Measures which were considered the least expensive to apply, such as provision of point-source enrichment objects, or provided wider production benefits, such as improvements in ventilation and herd health, became profitable at a lower level of efficacy than measures which were considered the most expensive to apply (e.g., straw provision, increased space allowance, automated early warning systems). Measures which were considered most efficient in reducing the risk of tail biting lesions, such as straw provision, can be cost-effective in preventing tail biting, especially when the risk of tail biting is high. At lower risk levels, the provision of point-source objects and other less costly but relatively effective measures can play an important role. However, selection of measures appropriate to the individual farm problem is essential. For instance, if poor health or barren pens are causing the elevated risk of tail biting lesions, then improving health management or enriching the pens may resolve the tail biting problem cost-effectively.
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Affiliation(s)
- Jarkko K Niemi
- Bioeconomy and Environment Unit, Natural Resources Institute Finland (Luke), Seinäjoki, Finland
| | - Sandra A Edwards
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | | | | | - Anna H Stygar
- Bioeconomy and Environment Unit, Natural Resources Institute Finland (Luke), Helsinki, Finland
| | - Anna Wallenbeck
- Department of Animal Environment and Health, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Anna Valros
- Research Centre for Animal Welfare, University of Helsinki, Helsinki, Finland
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Effectiveness of two intramuscular combined vaccines for the control of Mycoplasma hyopneumoniae and porcine circovirus type 2 in growing pigs: a randomized field trial. Porcine Health Manag 2021; 7:41. [PMID: 34176520 PMCID: PMC8237417 DOI: 10.1186/s40813-021-00220-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 05/19/2021] [Indexed: 11/23/2022] Open
Abstract
Background Mycoplasma hyopneumoniae and Porcine circovirus type 2 are two economically important pathogens affecting growing pigs. Control and prevention of both diseases can be accomplished by vaccination, together with biosecurity and good management practices. Many commercial vaccines are available. The aim of this study was to assess the efficacy of Hyogen® and Circovac® administered mixed at weaning and to compare this protocol with a competitor ready-to-use (RTU) vaccine. Case presentation A randomised field trial was designed in a commercial farrow-to-finish farm located in France. A total of 641 pigs born from 54 different sows were included in this study. Piglets at weaning were allocated into three groups: the first one vaccinated with Hyogen® and Circovac® combined (group A), the second one vaccinated with a competitor RTU vaccine (group B) and the last one unvaccinated. Only minor local reactions for both vaccination groups could be observed which revealed a good safety of both protocols. Both vaccination schemes in this trial didn’t improve wean-to-slaughter growth performances but significantly reduced lung lesions, lung fissures and pleurisy at slaughter, produced a seroconversion for both M. hyopneumoniae and PCV-2 and significantly reduced the PCV-2 viral load in blood. When we compared groups A and B, we observed no significant differences in growth performances, mortality, clinical signs, percentages of affected lungs at slaughter, lung fissures and pleurisy, and no difference in pathogens detection. However, two statistical differences were observed between both vaccines: the mean lung lesion score and the percentage of extensive lung lesions were lower in group A. This is consistent with lower M. hyopneumoniae loads in the lower respiratory tract in pigs from group A but this difference was not statistically significant. Conclusions Results reported in this case study must be considered with caution since it was done in only one farm. In this trial, Hyogen® and Circovac® mixed together under field conditions offered a successful protection of growing pigs and significantly decreased the extension of lung lesions during a natural field challenge when compared with a competitor RTU vaccine.
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Maes D, Boyen F, Devriendt B, Kuhnert P, Summerfield A, Haesebrouck F. Perspectives for improvement of Mycoplasma hyopneumoniae vaccines in pigs. Vet Res 2021; 52:67. [PMID: 33964969 PMCID: PMC8106180 DOI: 10.1186/s13567-021-00941-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 04/23/2021] [Indexed: 12/21/2022] Open
Abstract
Mycoplasma hyopneumoniae (M. hyopneumoniae) is one of the primary agents involved in the porcine respiratory disease complex, economically one of the most important diseases in pigs worldwide. The pathogen adheres to the ciliated epithelium of the trachea, bronchi, and bronchioles, causes damage to the mucosal clearance system, modulates the immune system and renders the animal more susceptible to other respiratory infections. The pathogenesis is very complex and not yet fully understood. Cell-mediated and likely also mucosal humoral responses are considered important for protection, although infected animals are not able to rapidly clear the pathogen from the respiratory tract. Vaccination is frequently practiced worldwide to control M. hyopneumoniae infections and the associated performance losses, animal welfare issues, and treatment costs. Commercial vaccines are mostly bacterins that are administered intramuscularly. However, the commercial vaccines provide only partial protection, they do not prevent infection and have a limited effect on transmission. Therefore, there is a need for novel vaccines that confer a better protection. The present paper gives a short overview of the pathogenesis and immune responses following M. hyopneumoniae infection, outlines the major limitations of the commercial vaccines and reviews the different experimental M. hyopneumoniae vaccines that have been developed and tested in mice and pigs. Most experimental subunit, DNA and vector vaccines are based on the P97 adhesin or other factors that are important for pathogen survival and pathogenesis. Other studies focused on bacterins combined with novel adjuvants. Very few efforts have been directed towards the development of attenuated vaccines, although such vaccines may have great potential. As cell-mediated and likely also humoral mucosal responses are important for protection, new vaccines should aim to target these arms of the immune response. The selection of proper antigens, administration route and type of adjuvant and carrier molecule is essential for success. Also practical aspects, such as cost of the vaccine, ease of production, transport and administration, and possible combination with vaccines against other porcine pathogens, are important. Possible avenues for further research to develop better vaccines and to achieve a more sustainable control of M. hyopneumoniae infections are discussed.
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Affiliation(s)
- Dominiek Maes
- Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - Filip Boyen
- Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Bert Devriendt
- Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Peter Kuhnert
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Artur Summerfield
- Institute of Virology and Immunology, Sensemattstrasse 293, Mittelhäusern, Switzerland.,Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
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Comparative Evaluation of Growth Performance between Bivalent and Trivalent Vaccines Containing Porcine Circovirus Type 2 (PCV2) and Mycoplasma hyopneumoniae in a Herd with Subclinical PCV2d Infection and Enzootic Pneumonia. Vaccines (Basel) 2021; 9:vaccines9050450. [PMID: 34063582 PMCID: PMC8147604 DOI: 10.3390/vaccines9050450] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 04/28/2021] [Accepted: 04/29/2021] [Indexed: 11/24/2022] Open
Abstract
The present field trial compared two combined vaccines of porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae, each administered in herd with subclinical PCV2d infection and enzootic pneumonia. One vaccine was a bivalent containing PCV2a and M. hyopneumoniae and the other was a trivalent vaccine containing PCV2a and 2b (PCV2a/b), and M. hyopneumoniae. The defining difference between these two vaccines was the inclusion or absence of PCV2b antigen. A total of 480, 21day-old pigs were randomly allocated to one of four treatment groups (120 pigs per group, male = 60 and female = 60). These groups included; one-dose trivalent-vaccinated, two-dose trivalent-vaccinated, one-dose bivalent-vaccinated, and unvaccinated. The one- and two-dose trivalent vaccinated pigs exhibited significantly better growth performance when compared with those vaccinated with the bivalent vaccine. The one- and two-dose trivalent vaccinated pigs also reduced the amount of PCV2d loads in the blood and feces, and resulted in a lower M. hyopneumoniae load in the larynx when compared with one-dose bivalent vaccinated pigs. Statistical differences were not observed between the one- and two-dose trivalent-vaccinated groups in terms of growth performance, serology, amount of PCV2d loads in the blood and feces, amount of M. hyopneumoniae load in larynx, and pathological lesions. The results of the present study will provide swine practitioners and producer with comparative clinical field data to select the proper vaccine and vaccination regiment for herds suffering from subclinical PCV2d infection and enzootic pneumonia.
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Blanc F, Maroilley T, Revilla M, Lemonnier G, Leplat JJ, Billon Y, Ravon L, Bouchez O, Bidanel JP, Bed'Hom B, Pinard-van der Laan MH, Estellé J, Rogel-Gaillard C. Influence of genetics and the pre-vaccination blood transcriptome on the variability of antibody levels after vaccination against Mycoplasma hyopneumoniae in pigs. Genet Sel Evol 2021; 53:24. [PMID: 33731010 PMCID: PMC7972226 DOI: 10.1186/s12711-021-00614-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 02/16/2021] [Indexed: 12/13/2022] Open
Abstract
Background The impact of individual genetic and genomic variations on immune responses is an emerging lever investigated in vaccination strategies. In our study, we used genetic and pre-vaccination blood transcriptomic data to study vaccine effectiveness in pigs. Results A cohort of 182 Large White pigs was vaccinated against Mycoplasma hyopneumoniae (M. hyo) at weaning (28 days of age), with a booster 21 days later. Vaccine response was assessed by measuring seric M. hyo antibodies (Ab) at 0 (vaccination day), 21 (booster day), 28, 35, and 118 days post-vaccination (dpv). Inter-individual variability of M. hyo Ab levels was observed at all time points and the corresponding heritabilities ranged from 0.46 to 0.57. Ab persistence was higher in females than in males. Genome-wide association studies with a 658 K SNP panel revealed two genomic regions associated with variations of M. hyo Ab levels at 21 dpv at positions where immunity-related genes have been mapped, DAB2IP on chromosome 1, and ASAP1, CYRIB and GSDMC on chromosome 4. We studied covariations of Ab responses with the pre-vaccination blood transcriptome obtained by RNA-Seq for a subset of 82 pigs. Weighted gene correlation network and differential expression analyses between pigs that differed in Ab responses highlighted biological functions that were enriched in heme biosynthesis and platelet activation for low response at 21 dpv, innate antiviral immunity and dendritic cells for high response at 28 and 35 dpv, and cell adhesion and extracellular matrix for high response at 118 dpv. Sparse partial least squares discriminant analysis identified 101 genes that efficiently predicted divergent responders at all time points. We found weak negative correlations of M. hyo Ab levels with body weight traits, which revealed a trade-off that needs to be further explored. Conclusions We confirmed the influence of the host genetics on vaccine effectiveness to M. hyo and provided evidence that the pre-vaccination blood transcriptome co-varies with the Ab response. Our results highlight that both genetic markers and blood biomarkers could be used as potential predictors of vaccine response levels and more studies are required to assess whether they can be exploited in breeding programs.
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Affiliation(s)
- Fany Blanc
- Université Paris-Saclay, INRAE, AgroParisTech, GABI, 78350, Jouy-en-Josas, France.
| | - Tatiana Maroilley
- Université Paris-Saclay, INRAE, AgroParisTech, GABI, 78350, Jouy-en-Josas, France
| | - Manuel Revilla
- Université Paris-Saclay, INRAE, AgroParisTech, GABI, 78350, Jouy-en-Josas, France
| | - Gaëtan Lemonnier
- Université Paris-Saclay, INRAE, AgroParisTech, GABI, 78350, Jouy-en-Josas, France
| | - Jean-Jacques Leplat
- Université Paris-Saclay, INRAE, AgroParisTech, GABI, 78350, Jouy-en-Josas, France
| | | | | | | | - Jean-Pierre Bidanel
- Université Paris-Saclay, INRAE, AgroParisTech, GABI, 78350, Jouy-en-Josas, France
| | - Bertrand Bed'Hom
- Université Paris-Saclay, INRAE, AgroParisTech, GABI, 78350, Jouy-en-Josas, France
| | | | - Jordi Estellé
- Université Paris-Saclay, INRAE, AgroParisTech, GABI, 78350, Jouy-en-Josas, France
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Betlach AM, Fano E, VanderWaal K, Pieters M. Effect of multiple vaccinations on transmission and degree of Mycoplasma hyopneumoniae infection in gilts. Vaccine 2020; 39:767-774. [PMID: 33342634 DOI: 10.1016/j.vaccine.2020.10.096] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 10/23/2020] [Accepted: 10/30/2020] [Indexed: 01/26/2023]
Abstract
Mycoplasma hyopneumoniae (M. hyopneumoniae) infections continue to result in significant respiratory challenges in the swine industry worldwide. Vaccination for M. hyopneumoniae is commonly utilized, as reduction in bacterial loads and clinical severity in vaccinated pigs have been shown. However, the effect of M. hyopneumoniae vaccination on transmission across different pig populations has been minimally investigated. The aim of this pilot study was to evaluate the effect of multiple vaccinations on M. hyopneumoniae infection, transmission, and genetic variability in infected and susceptible gilt populations. Thirty-two naïve gilts were allocated to four treatment groups: (1) Vaccinated seeder (VS); (2) Non-vaccinated seeder (NVS); (3) Vaccinated contact (VC); and (4) Non-vaccinated contact (NVC). At 5, 7, and 9 weeks of age, all gilts selected to be vaccinated received a commercial M. hyopneumoniae bacterin for a total of 3 doses. At 11 weeks of age, VS and NVS gilts were inoculated with M. hyopneumoniae to become seeders. At 28 days post-inoculation (dpi), VS and NVS gilts were individually relocated to clean experimental rooms, where they were placed in contact with one age-matched VC or NVC gilt (1:1 ratio) for 14 days. Blood and tracheal samples, bronchial swabs, and lung lesions were collected and/or evaluated for M. hyopneumoniae infection. In this study, a three-dose vaccination strategy against M. hyopneumoniae significantly reduced bacterial load in seeder gilts. Furthermore, a numerical reduction in M. hyopneumoniae lung lesions at 28 dpi was observed in VS gilts. All VC gilts in the VS:VC treatment group pairing remained M. hyopneumoniae negative, compared to other groups in which 1-2 transmission events occurred per treatment group. Results from this investigation provide insight on the potential impact of multiple vaccinations on reducing M. hyopneumoniae transmission and infection. Further research encompassing vaccinations of gilt groups in field settings is necessary to validate findings.
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Affiliation(s)
- Alyssa M Betlach
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA; Swine Vet Center, St. Peter, MN, USA
| | - Eduardo Fano
- Boehringer Ingelheim Animal Health USA Inc., Duluth, GA, USA
| | - Kimberly VanderWaal
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA
| | - Maria Pieters
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA.
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Fitzgerald RM, O'Shea H, Manzanilla EG, Moriarty J, McGlynn H, Calderón Díaz JA. Associations between animal and herd management factors, serological response to three respiratory pathogens and pluck lesions in finisher pigs on a farrow-to-finish farm. Porcine Health Manag 2020; 6:34. [PMID: 33292673 PMCID: PMC7722331 DOI: 10.1186/s40813-020-00173-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 10/18/2020] [Indexed: 11/18/2022] Open
Abstract
Background Serological screening is a common method to monitor antibody response to pathogen exposure, but results could vary due to several factors. This study aimed to quantify animal and management related factors associated with variation in antibody levels in finisher pigs at slaughter, in an Irish farrow-to-finish farm endemically infected with Actinobacillus pleuropneumonia (App), Mycoplasma hyopneumoniae (Mhyo) and swine influenza virus (SIV). A second objective was to estimate differences in antibody levels in pigs presenting pluck lesions. This was an observational study whereby pigs were managed as per routine farm practice. Data on sow parity, number of born alive (NBA) pigs per litter, cross-fostering status, birth and weaning body weight were recorded from 1016 pigs born from one farrowing batch. At slaughter, blood samples were collected for serological analysis and pigs were inspected for presence of enzootic pneumonia (EP)-like lesions, pleurisy, pericarditis and heart condemnations. Pigs were retrospectively classified into three production flows, depending on time spent in each production stage: flow 1 (F1; pigs followed the normal production flow); flow 2 (F2; pigs which were delayed by 1 week from advancing forward); and flow 3 (F3; pigs delayed by > 1 week from advancing forward). A nested case-control design was applied by matching pigs from each flow by sow parity, birth weight and NBA. Results Pigs born from primiparous sows had higher antibody levels for App than those born to parity ≥5 sows (P < 0.05) and there was no association between any of the pathogens investigated and other early life indicators (P > 0.05). Pigs in F1 had lower antibody levels for App but higher antibody levels for SIV than F2 and F3 pigs (P < 0.05). There was no association between pluck lesions and respiratory pathogens (P > 0.05), except for increased antibody levels for Mhyo when EP-like lesions were present (P = 0.006). Conclusion Results indicate that offspring from primiparous sows develop higher antibody levels for App IV toxin when exposed to this disease and that enforcement of a strict all-in/all-out production system would reduce on-farm disease circulation. A high percentage of pigs were affected with EP-like lesions which were associated with higher antibody levels for Mhyo.
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Affiliation(s)
- Rose Mary Fitzgerald
- Bio-Explore, Department of Biological Sciences, Cork Institute of Technology, Rossa Avenue, Bishopstown, Cork, T12 P928, Ireland
| | - Helen O'Shea
- Bio-Explore, Department of Biological Sciences, Cork Institute of Technology, Rossa Avenue, Bishopstown, Cork, T12 P928, Ireland
| | - Edgar García Manzanilla
- Pig Development Department, Teagasc Animal and Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, P61 C996, Ireland. .,School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, D04 V1W8, Ireland.
| | - John Moriarty
- Central Veterinary Research Laboratory, Department of Agriculture, Food and the Marine Laboratories, Backweston, Celbridge, Co. Kildare, W23 X3PH, Ireland
| | - Hugh McGlynn
- Bio-Explore, Department of Biological Sciences, Cork Institute of Technology, Rossa Avenue, Bishopstown, Cork, T12 P928, Ireland
| | - Julia Adriana Calderón Díaz
- Pig Development Department, Teagasc Animal and Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, P61 C996, Ireland
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Pessoa J, Rodrigues da Costa M, García Manzanilla E, Norton T, McAloon C, Boyle L. Managing respiratory disease in finisher pigs: Combining quantitative assessments of clinical signs and the prevalence of lung lesions at slaughter. Prev Vet Med 2020; 186:105208. [PMID: 33310195 DOI: 10.1016/j.prevetmed.2020.105208] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 11/05/2020] [Accepted: 11/09/2020] [Indexed: 10/23/2022]
Abstract
This study aimed to assess the relationship between quantitative assessments of clinical signs of respiratory disease (recorded manually and automatically) and the prevalence of lung lesions at slaughter to validate the use of both in the management of respiratory disease on farm. This was an observational study where pigs (n = 1573) were monitored from 25 ± 5.3 kg (week 12) to slaughter at 114 ± 15.4 kg (week 24). Pigs were housed in eight rooms divided into six pens on a wean-to-finish farm. A manual pen-based coughing (CF) and sneezing (SF) frequency was recorded weekly, for ten consecutive weeks, and a SOMO box (SoundTalks®) was installed in each room, issuing a daily respiratory distress index (RDI) for 13 weeks. Lungs were individually scored for pneumonia, scarring and dorsocaudal (DC) and cranial (CP) pleurisy lesions at slaughter. Relationship between prevalence of lung lesions and weekly RDI and CF and SF was assessed using Spearman's rank correlations and multivariable linear and logit-normal models. Both coughing and lung lesions were largely pen-specific, which fit the disease presentation of Mycoplasma hyopneumoniae. Results showed agreement between RDI and CF (rs = 0.5, P < 0.001), measuring higher levels of coughing at the beginning (weeks 13-14) and end (weeks 21-24, and weeks 21-22, respectively) of the finisher period. Positive associations were found between the prevalence of pneumonia and CF on week 21 and 22 (P < 0.001 and P = 0.011, respectively) and RDI on week 21-24 (rs > 0.70; P < 0.050); the prevalence of DC and CP, and CF on week 22 (P < 0.001); and prevalence of scar lesions and CF on week 17 and 21 (P = 0.013 and P = 0.004, respectively), and RDI on week 21-24 (rs > 0.70; P < 0.050). In the earlier weeks of the finisher stage, coughing was recorded but was not reflected in a higher prevalence of lung lesions at slaughter. These findings highlight the benefit of including measurements of coughing frequency to complement post mortem findings, to improve the management of respiratory disease on farm.
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Affiliation(s)
- Joana Pessoa
- Pig Development Department, Teagasc Animal and Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland; Section of Herd Health and Animal Husbandry, School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland; M3-BIORES-Measure, Model & Manage Bioresponses, KU Leuven, Kasteelpark Arenberg 30, B-3001, Leuven, Belgium.
| | - Maria Rodrigues da Costa
- Pig Development Department, Teagasc Animal and Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland; Section of Herd Health and Animal Husbandry, School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland
| | - Edgar García Manzanilla
- Pig Development Department, Teagasc Animal and Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland; Section of Herd Health and Animal Husbandry, School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland
| | - Tomas Norton
- M3-BIORES-Measure, Model & Manage Bioresponses, KU Leuven, Kasteelpark Arenberg 30, B-3001, Leuven, Belgium
| | - Conor McAloon
- Section of Herd Health and Animal Husbandry, School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland
| | - Laura Boyle
- Pig Development Department, Teagasc Animal and Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland
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12
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Calderón Díaz JA, Fitzgerald RM, Shalloo L, Rodrigues da Costa M, Niemi J, Leonard FC, Kyriazakis I, García Manzanilla E. Financial Analysis of Herd Status and Vaccination Practices for Porcine Reproductive and Respiratory Syndrome Virus, Swine Influenza Virus, and Mycoplasma hyopneumoniae in Farrow-to-Finish Pig Farms Using a Bio-Economic Simulation Model. Front Vet Sci 2020; 7:556674. [PMID: 33240946 PMCID: PMC7680737 DOI: 10.3389/fvets.2020.556674] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 10/13/2020] [Indexed: 11/25/2022] Open
Abstract
This study aimed (1) to quantify the effects of positive status and vaccination practices for porcine reproductive and respiratory syndrome virus (PRRSv), swine influenza virus (SIV) and Mycoplasma hyopneumoniae (MHYO) on the profitability of farrow-to-finish pig farms and (2) to examine the financial impact of vaccination status in PRRSv and SIV positive farms. Data from 56 Irish farrow-to-finish pig farms were used for this study. Production effects associated with herd status for the three pathogens were incorporated into the Teagasc Pig Production Model (TPPM), a bio-economic stochastic simulation model for farrow-to-finish pig farms. In the analysis, farms negative (–) for either PRRSv, SIV or MHYO were assumed as baseline when presenting results for farms positive (+) for each pathogen. While all MHYO(+) farms used vaccination against the pathogen, not all PRRSv(+) or SIV(+) farms vaccinated against the disease. For all scenarios, a 728-sow farrow-to-finish farm with weekly farrowing batches was simulated. Financial risk analysis was conducted by Monte Carlo simulation within the TPPM using the Microsoft Excel add-in @Risk. Mortality rates, feedstuff costs and price per kg of meat produced were included as input stochastic variables and annual net profit was set as stochastic output variable. Positive farms sold fewer pigs and produced less kg of meat than negative farms and had increased feed usage during the weaner and finisher stages. Variable costs increased in positive farms due to increased feed costs, more dead animals for disposal and healthcare costs. Annual mean profit was lower by 24% in vaccinated PRRSv(+), 14.6% in unvaccinated PRRSv(+), 36.7% in vaccinating SIV(+), 12.8% in unvaccinated SIV(+), and 41% in MHYO(+) farms. Negative farms were first order stochastically dominant over positive farms, indicating that for a given level of profit, the financial risk is lower by avoiding respiratory pathogens. Similarly, unvaccinated farms were second order stochastically dominant over vaccinating farms suggesting that farms that do not vaccinate are less affected by the disease. Results from this study provide further evidence to encourage farmers to undertake improved disease control measures and/or to implement eradication programs.
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Affiliation(s)
| | - Rose Mary Fitzgerald
- Bio-Explore, Department of Biological Sciences, Cork Institute of Technology, Bishopstown, Ireland
| | - Laurence Shalloo
- Livestock Production Systems, Teagasc Animal and Grassland Research and Innovation Centre, Fermoy, Ireland
| | - Maria Rodrigues da Costa
- Pig Development Department, Teagasc Animal and Grassland Research and Innovation Centre, Fermoy, Ireland.,School of Veterinary Medicine, University College Dublin, Dublin, Ireland
| | - Jarkko Niemi
- Natural Resources Institute Finland (LUKE), Seinäjoki, Finland
| | - Finola C Leonard
- School of Veterinary Medicine, University College Dublin, Dublin, Ireland
| | - Ilias Kyriazakis
- Institute for Global Food Security, Queen's University of Belfast, Belfast, United Kingdom
| | - Edgar García Manzanilla
- Pig Development Department, Teagasc Animal and Grassland Research and Innovation Centre, Fermoy, Ireland.,School of Veterinary Medicine, University College Dublin, Dublin, Ireland
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13
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Gebhardt JT, Tokach MD, Dritz SS, DeRouchey JM, Woodworth JC, Goodband RD, Henry SC. Postweaning mortality in commercial swine production II: review of infectious contributing factors. Transl Anim Sci 2020; 4:txaa052. [PMID: 32705048 PMCID: PMC7277696 DOI: 10.1093/tas/txaa052] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 04/27/2020] [Indexed: 11/14/2022] Open
Abstract
Postweaning mortality is extremely complex with a multitude of noninfectious and infectious contributing factors. In the current review, our objective is to describe the current state of knowledge regarding infectious causes of postweaning mortality, focusing on estimates of frequency and magnitude of effect where available. While infectious mortality is often categorized by physiologic body system affected, we believe the complex multifactorial nature is better understood by an alternative stratification dependent on intervention type. This category method subjectively combines disease pathogenesis knowledge, epidemiology, and economic consequences. These intervention categories included depopulation of affected cohorts of animals, elimination protocols using knowledge of immunity and epidemiology, or less aggressive interventions. The most aggressive approach to control infectious etiologies is through herd depopulation and repopulation. Historically, these protocols were successful for Actinobacillus pleuropneumoniae and swine dysentery among others. Additionally, this aggressive measure likely would be used to minimize disease spread if either a foreign animal disease was introduced or pseudorabies virus was reintroduced into domestic swine populations. Elimination practices have been successful for Mycoplasma hyopneumoniae, porcine reproductive and respiratory syndrome virus, coronaviruses, including transmissible gastroenteritis virus, porcine epidemic diarrhea virus, and porcine deltacoronavirus, swine influenza virus, nondysentery Brachyspira spp., and others. Porcine circovirus type 2 can have a significant impact on morbidity and mortality; however, it is often adequately controlled through immunization. Many other infectious etiologies present in swine production have not elicited these aggressive control measures. This may be because less aggressive control measures, such as vaccination, management, and therapeutics, are effective, their impact on mortality or productivity is not great enough to warrant, or there is inadequate understanding to employ control procedures efficaciously and efficiently. Since there are many infectious agents and noninfectious contributors, emphasis should continue to be placed on those infectious agents with the greatest impact to minimize postweaning mortality.
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Affiliation(s)
- Jordan T Gebhardt
- Department of Animal Sciences and Industry, College of Agriculture, Kansas State University, Manhattan, KS
| | - Mike D Tokach
- Department of Animal Sciences and Industry, College of Agriculture, Kansas State University, Manhattan, KS
| | - Steve S Dritz
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS
| | - Joel M DeRouchey
- Department of Animal Sciences and Industry, College of Agriculture, Kansas State University, Manhattan, KS
| | - Jason C Woodworth
- Department of Animal Sciences and Industry, College of Agriculture, Kansas State University, Manhattan, KS
| | - Robert D Goodband
- Department of Animal Sciences and Industry, College of Agriculture, Kansas State University, Manhattan, KS
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14
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High biosecurity and welfare standards in fattening pig farms are associated with reduced antimicrobial use. Animal 2020; 14:2178-2186. [PMID: 32349838 DOI: 10.1017/s1751731120000828] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In order to reduce antimicrobial use in pig production, the consequences of insufficient biosecurity and welfare problems need to be known. This study aimed to investigate associations between the number of antimicrobial treatments per fattening pig, and biosecurity, indicators for animal welfare as well as the prevalence of lesions at slaughter. The data used in this study were extracted from the pig health and welfare classification system (Sikava), which gathers data on medicine usage, meat inspection, animal welfare and the condition of farm buildings from over 95% of pig production in Finland. The data were registered during years from 2011 to 2013. Upon antimicrobial prescription, information on the number of fattening pigs treated and the main reason for treatment was recorded. In addition, at least 4 times per year, pig farms registered in Sikava were visited by the farm veterinarian who assessed, among other things, biosecurity and indicators for animal welfare (air quality, condition of facilities, cleanliness, enrichment and stocking density). Finally, data from slaughterhouse inspections were collected (number of carcasses with joint infection, abscesses, lung lesions, pleurisy and liver lesions). For analysis, these datasets were aggregated at the farm level to a quarter of a year. During the studied period, the mean number of antimicrobial treatments per fattening pig per 3 months was equal to 0.09. The main reasons for antimicrobial treatments were musculoskeletal diseases, tail biting and respiratory disorders (42, 33 and 12% of diagnoses, respectively). The meat inspection scoring indicated that as much as 14.7% of all pigs had pleurisy, 5.3% liver lesions and 4.1% abscesses. A standard zero-inflated negative binomial model was used to identify factors associated with the number of antimicrobial treatments per pig. The count of antimicrobial treatments per pig increased with the size of a farm. Regardless of prevalence of lesions, farms with poor drinking equipment, insufficient enrichment and a combination of poor condition of pens and high stocking density were associated with an increased number of antimicrobial treatments for musculoskeletal diseases per pig. Problems with stocking density and enrichment were associated with the number of antimicrobial treatments for tail biting, although these results depended on prevalence of joint infections. Problems with air quality and the combination of poor cleanliness and poor condition of facilities were associated with increased number of antimicrobial treatments due to respiratory diseases. This study suggests that by improving biosecurity and welfare at pig farms, antimicrobial use can be reduced.
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15
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Matthijs AMF, Auray G, Boyen F, Schoos A, Michiels A, García-Nicolás O, Barut GT, Barnier-Quer C, Jakob V, Collin N, Devriendt B, Summerfield A, Haesebrouck F, Maes D. Efficacy of three innovative bacterin vaccines against experimental infection with Mycoplasma hyopneumoniae. Vet Res 2019; 50:91. [PMID: 31703726 PMCID: PMC6842239 DOI: 10.1186/s13567-019-0709-0] [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: 06/14/2019] [Accepted: 09/25/2019] [Indexed: 12/31/2022] Open
Abstract
New vaccine formulations that include novel strains of Mycoplasma hyopneumoniae and innovative adjuvants designed to induce cellular immunity could improve vaccine efficacy against this pathogen. The aim of this experimental study was to assess the efficacy of three experimental bacterin formulations based on M. hyopneumoniae field strain F7.2C which were able to induce cellular immunity. The formulations included a cationic liposome formulation with the Mincle receptor ligand trehalose 6,6-dibehenate (Lipo_DDA:TDB), a squalene-in-water emulsion with Toll-like receptor (TLR) ligands targeting TLR1/2, TLR7/8 and TLR9 (SWE_TLR), and a poly(lactic-co-glycolic acid) micro-particle formulation with the same TLR ligands (PLGA_TLR). Four groups of 12 M. hyopneumoniae-free piglets were primo- (day (D) 0; 39 days of age) and booster vaccinated (D14) intramuscularly with either one of the three experimental bacterin formulations or PBS. The pigs were endotracheally inoculated with a highly and low virulent M. hyopneumoniae strain on D28 and D29, respectively, and euthanized on D56. The main efficacy parameters were: respiratory disease score (RDS; daily), macroscopic lung lesion score (D56) and log copies M. hyopneumoniae DNA determined with qPCR on bronchoalveolar lavage (BAL) fluid (D42, D56). All formulations were able to reduce clinical symptoms, lung lesions and the M. hyopneumoniae DNA load in the lung, with formulation SWE_TLR being the most effective (RDSD28–D56 −61.90%, macroscopic lung lesions −88.38%, M. hyopneumoniae DNA load in BAL fluid (D42) −67.28%). Further experiments raised under field conditions are needed to confirm these results and to assess the effect of the vaccines on performance parameters.
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Affiliation(s)
- Anneleen Marguerite Filip Matthijs
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium.
| | - Gaël Auray
- Institute of Virology and Immunology, Sensemattstrasse 293, 3147, Mittelhäusern, Switzerland.,Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Länggassstrasse 120, 3012, Bern, Switzerland
| | - Filip Boyen
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
| | - Alexandra Schoos
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
| | - Annelies Michiels
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
| | - Obdulio García-Nicolás
- Institute of Virology and Immunology, Sensemattstrasse 293, 3147, Mittelhäusern, Switzerland.,Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Länggassstrasse 120, 3012, Bern, Switzerland
| | - Güliz Tuba Barut
- Institute of Virology and Immunology, Sensemattstrasse 293, 3147, Mittelhäusern, Switzerland.,Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Länggassstrasse 120, 3012, Bern, Switzerland
| | - Christophe Barnier-Quer
- Vaccine Formulation Laboratory, University of Lausanne, Chemin des Boveresses 155, 1066, Epalinges, Switzerland
| | - Virginie Jakob
- Vaccine Formulation Laboratory, University of Lausanne, Chemin des Boveresses 155, 1066, Epalinges, Switzerland
| | - Nicolas Collin
- Vaccine Formulation Laboratory, University of Lausanne, Chemin des Boveresses 155, 1066, Epalinges, Switzerland
| | - Bert Devriendt
- Laboratory of Veterinary Immunology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
| | - Artur Summerfield
- Institute of Virology and Immunology, Sensemattstrasse 293, 3147, Mittelhäusern, Switzerland.,Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Länggassstrasse 120, 3012, Bern, Switzerland
| | - Freddy Haesebrouck
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
| | - Dominiek Maes
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
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16
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Jansen T, Weersink A, von Massow M, Poljak Z. Assessing the Value of Antibiotics on Farms: Modeling the Impact of Antibiotics and Vaccines for Managing Lawsonia intracellularis in Hog Production. Front Vet Sci 2019; 6:364. [PMID: 31681817 PMCID: PMC6813653 DOI: 10.3389/fvets.2019.00364] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 10/02/2019] [Indexed: 11/13/2022] Open
Abstract
Increasing awareness of antibiotic resistance has correspondingly increased efforts to identify and reduce the causal behaviors that led to this severe public health threat. The consequences of these efforts are regulatory and market pressures limiting antibiotic use by livestock farmers which may lead to significant financial and welfare challenges on the farm, even if antibiotics can be substituted by vaccines. The purpose of this study is to measure the relative cost-effectiveness of antibiotics vs. vaccines for controlling L. intracellularis on a Canadian farrow-to-finish pig farm. This is done by modeling the production and economic impact of different antibiotics and vaccines available for managing this disease, listed in the Canadian Compendium of Veterinary Products. The economic impacts (in Canadian dollars) of the disease are estimated and the net benefits of alternative prevention and treatment options are compared to determine the relative cost-effectiveness of each strategy. Of the 12 options analyzed, four were preventative (antibiotic and vaccine) and eight were antibiotic treatments. Prophylactic chlortetracycline (an antibiotic) is the most cost-effective option for managing L. intracellularis, while Porcilis Ileitis (a vaccine) is the least cost-effective strategy. This result remains robust considering sensitivity analysis of the production parameters, which indicates that preventative antibiotics are more cost-effective than vaccines. This implies that banning preventative antibiotic treatments harms the bottom line of farmers under current market conditions.
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Affiliation(s)
- Travis Jansen
- Department of Food, Agricultural and Resource Economics, University of Guelph, Guelph, ON, Canada
| | - Alfons Weersink
- Department of Food, Agricultural and Resource Economics, University of Guelph, Guelph, ON, Canada
| | - Michael von Massow
- Department of Food, Agricultural and Resource Economics, University of Guelph, Guelph, ON, Canada
| | - Zvonomir Poljak
- Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
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17
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Baraldi TG, Cruz NRN, Pereira DA, Galdeano JVB, Gatto IRH, Silva AFD, Panzardi A, Linhares DCL, Mathias LA, de Oliveira LG. Antibodies against Actinobacillus pleuropneumoniae, Mycoplasma hyopneumoniae and influenza virus and their relationships with risk factors, clinical signs and lung lesions in pig farms with one-site production systems in Brazil. Prev Vet Med 2019; 171:104748. [PMID: 31470290 DOI: 10.1016/j.prevetmed.2019.104748] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 08/04/2019] [Accepted: 08/18/2019] [Indexed: 10/26/2022]
Abstract
A study was conducted on 21 pig herds using one-site production system in the southeast region of Brazil to assess the relationships among serological results for primary pathogens involved in respiratory diseases (Actinobacillus pleuropneumoniae, App; Mycoplasma hyopneumoniae, Mhyo; and swine influenza virus, SIV), cough index, pneumonia index, pleuritis and herd characteristics. The prevalence of antibodies against Mhyo and SIV increased throughout the raising phases, with the highest prevalence in slaughtered pigs (> 40%), while pigs in 65% (14/21) of nurseries demonstrated marked seroprevalence of App that decreased until the day of slaughter. Pleuritis and pulmonary consolidations were recorded in 9.0 and 72.4%, respectively, of the 908 evaluated lungs. Histopathological analysis of the lung lesions revealed suppurative bronchopneumonia in almost half of the lungs (48.9%). Regression analyses were conducted to identify risk factors associated with the cough index; pleuritis; pulmonary consolidation; and App, Mhyo and SIV serological results. All-in-all-out management in nursery buildings reduced the seroprevalence of Mhyo in herds. App seroprevalence was associated with pleuritis, and the presence of cough episodes in growing pigs was associated with SIV seropositivity in nursery pigs.
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Affiliation(s)
- T G Baraldi
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - N R N Cruz
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - D A Pereira
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - J V B Galdeano
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - I R H Gatto
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | | | | | - D C L Linhares
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, United States
| | - L A Mathias
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - L G de Oliveira
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil.
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18
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Benefit-cost analysis to estimate the payback time and the economic value of two Mycoplasma hyopneumoniae elimination methods in breeding herds. Prev Vet Med 2019; 168:95-102. [PMID: 31097130 DOI: 10.1016/j.prevetmed.2019.04.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 04/16/2019] [Accepted: 04/16/2019] [Indexed: 11/21/2022]
Abstract
Mycoplasma hyopneumoniae (Mhyo) is generally accepted to be the most common porcine respiratory pathogen worldwide causing big economical losses in swine production by affecting pig's downstream performance. The objective of this study was to develop a partial budget model to determine the payback period and economic value of two Mhyo elimination protocols. Retrospective data recorded from 2004 to 2017 from 70 breeding herds that implemented herd closure or whole-herd medication protocol targeting Mhyo elimination. Close out data was used to estimate differences in downstream performance between Mhyo-negative and positive flows. Assuming a 5000 sows breed-to-finish operation producing 135,870 weaned pigs and 125,000 finishing pigs/year, the total cost for implementing Mhyo elimination was $112,100 using the herd closure protocol, and $185,700 for the medication protocol. Statistically differences (p < 0.05) in downstream performance were observed for ADG and mortality, but not for feed conversion rate. The parameters that accounts for the greatest benefits were related to the improvement in ADG, savings in antibiotic medication in growing pigs and improvement in feed conversion rate. The benefit of Mhyo elimination was $877,375 per farm per year, or $7.00 per pig marketed. The estimated project value after 1 year was $616,121 for the herd closure considering a probability of success of 83%, and $323,177 for the medication protocol for 58% chance of success. The project value reached the break-even point when the cost per sow was $145.64 for the herd closure and $101.78 for the medication protocol. The payback period was 2 months after the start of marketing Mhyo-negative pigs for the herd closure, and 7 months for the medication protocol adjusted for the probability of success for each protocol. The protocols described here can be easily applied with a good success rate and showing that the benefits obtained are greater than the costs of project failure. Even if the farm stayed negative only a year, the economic benefits downstream are worth the investment. This information may help producers and veterinarians on decision-making process to conduct a Mhyo elimination protocol in their herds.
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19
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Fablet C, Rose N, Grasland B, Robert N, Lewandowski E, Gosselin M. Factors associated with the growing-finishing performances of swine herds: an exploratory study on serological and herd level indicators. Porcine Health Manag 2018; 4:6. [PMID: 29588859 PMCID: PMC5863451 DOI: 10.1186/s40813-018-0082-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 01/22/2018] [Indexed: 12/20/2022] Open
Abstract
Background Growing and finishing performances of pigs strongly influence farm efficiency and profitability. The performances of the pigs rely on the herd health status and also on several non-infectious factors. Many recommendations for the improvement of the technical performances of a herd are based on the results of studies assessing the effect of one or a limited number of infections or environmental factors. Few studies investigated jointly the influence of both type of factors on swine herd performances. This work aimed at identifying infectious and non-infectious factors associated with the growing and finishing performances of 41 French swine herds. Results Two groups of herds were identified using a clustering analysis: a cluster of 24 herds with the highest technical performance values (mean average daily gain = 781.1 g/day +/− 26.3; mean feed conversion ratio = 2.5 kg/kg +/− 0.1; mean mortality rate = 4.1% +/− 0.9; and mean carcass slaughter weight = 121.2 kg +/− 5.2) and a cluster of 17 herds with the lowest performance values (mean average daily gain =715.8 g/day +/− 26.5; mean feed conversion ratio = 2.6 kg/kg +/− 0.1; mean mortality rate = 6.8% +/− 2.0; and mean carcass slaughter weight = 117.7 kg +/− 3.6). Multiple correspondence analysis was used to identify factors associated with the level of technical performance. Infection with the porcine reproductive and respiratory syndrome virus and the porcine circovirus type 2 were infectious factors associated with the cluster having the lowest performance values. This cluster also featured farrow-to-finish type herds, a short interval between successive batches of pigs (≤3 weeks) and mixing of pigs from different batches in the growing or/and finishing steps. Inconsistency between nursery and fattening building management was another factor associated with the low-performance cluster. The odds of a herd showing low growing-finishing performance was significantly increased when infected by PRRS virus in the growing-finishing steps (OR = 8.8, 95% confidence interval [95% CI]: 1.8–41.7) and belonging to a farrow-to-finish type herd (OR = 5.1, 95% CI = 1.1–23.8). Conclusions Herd management and viral infections significantly influenced the performance levels of the swine herds included in this study. Electronic supplementary material The online version of this article (10.1186/s40813-018-0082-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- C Fablet
- 1Agence Nationale de Sécurité Sanitaire de l'alimentation, de l'environnement et du travail (Anses), Laboratoire de Ploufragan/Plouzané, Unité Epidémiologie et Bien-Etre du Porc, B.P. 53, 22440 Ploufragan, France.,Université Bretagne-Loire, Cité internationale 1 place Paul Ricoeur CS 54417, 35044 Rennes, France
| | - N Rose
- 1Agence Nationale de Sécurité Sanitaire de l'alimentation, de l'environnement et du travail (Anses), Laboratoire de Ploufragan/Plouzané, Unité Epidémiologie et Bien-Etre du Porc, B.P. 53, 22440 Ploufragan, France.,Université Bretagne-Loire, Cité internationale 1 place Paul Ricoeur CS 54417, 35044 Rennes, France
| | - B Grasland
- 2Agence Nationale de Sécurité Sanitaire de l'alimentation, de l'environnement et du travail (Anses), Laboratoire de Ploufragan/Plouzané, Unité Génétique Virale et Biosécurité, B.P. 53, 22440 Ploufragan, France.,Université Bretagne-Loire, Cité internationale 1 place Paul Ricoeur CS 54417, 35044 Rennes, France
| | - N Robert
- 3Boehringer Ingelheim France - Santé Animale, Les Jardins de la Teillais, 3 allée de la grande Egalonne, 35740 Pacé, France
| | - E Lewandowski
- 3Boehringer Ingelheim France - Santé Animale, Les Jardins de la Teillais, 3 allée de la grande Egalonne, 35740 Pacé, France
| | - M Gosselin
- Univet Santé Elevage, rue Monge, 22600 Loudéac, France
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Beffort L, Weiß C, Fiebig K, Jolie R, Ritzmann M, Eddicks M. Field study on the safety and efficacy of intradermal versus intramuscular vaccination against Mycoplasma hyopneumoniae. Vet Rec 2017; 181:348. [PMID: 28893974 DOI: 10.1136/vr.104466] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 06/28/2017] [Accepted: 07/24/2017] [Indexed: 11/04/2022]
Abstract
The present study compares the safety and efficacy of a needle-free, intradermal Mycoplasma hyopneumoniae vaccine to an intramuscular one. 420 piglets (21+3 days of age) were randomly assigned to two vaccination groups (intradermal vaccination V1 (n=138), intramuscular vaccination V2 (n=144)) and one unvaccinated control group (CG, n=138). As safety parameters clinical observations, local injection site reactions (ISR) and rectal temperatures were assessed. Average daily weight gain (ADWG) and pneumonic lung lesions (LL) were measured as efficacy parameters. ISRs were minor in V1. After both vaccinations, no adverse impact on appetite was observed and mean rectal temperatures remained within physiological range. ADWG during the fattening period was significantly higher in vaccinated groups (V1: 913.4 g, V2: 924.5 g) compared with CG (875.6 g). No differences in ADWG were observed between V1 and V2. Vaccinated pigs had a significantly reduced mean extent of LL compared with CG. V1 was superior in reducing the extent and prevalence of LL compared with V2. These results reveal that a needle-free intradermal vaccination is safe and efficacious in reducing both the prevalence and extent of lung lesions, as well as in improving performance parameters, in a farrow-to-finish farm with a late onset of M hyopneumoniae infection.
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Affiliation(s)
- Lisa Beffort
- Clinic for Swine, Centre for Clinical Veterinary Medicine, LMU Munich, Oberschleissheim, Germany
| | - Christine Weiß
- Clinic for Swine, Centre for Clinical Veterinary Medicine, LMU Munich, Oberschleissheim, Germany
| | | | - Rika Jolie
- MSD Animal Health, Madison, New Jersey, USA
| | - Mathias Ritzmann
- Clinic for Swine, Centre for Clinical Veterinary Medicine, LMU Munich, Oberschleissheim, Germany
| | - Matthias Eddicks
- Clinic for Swine, Centre for Clinical Veterinary Medicine, LMU Munich, Oberschleissheim, Germany
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21
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Michiels A, Arsenakis I, Boyen F, Krejci R, Haesebrouck F, Maes D. Efficacy of one dose vaccination against experimental infection with two Mycoplasma hyopneumoniae strains. BMC Vet Res 2017; 13:274. [PMID: 28851359 PMCID: PMC5576127 DOI: 10.1186/s12917-017-1195-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 08/11/2017] [Indexed: 11/14/2022] Open
Abstract
Background Mycoplasma hyopneumoniae (M. hyopneumoniae) is the primary agent of enzootic pneumonia in pigs. Pigs are often infected with different M. hyopneumoniae strains. This study assessed the efficacy of vaccination against experimental infection with two genetically different M. hyopneumoniae strains in weaned piglets. At 33 days of age (D0), 45 M. hyopneumoniae-free piglets were randomly assigned to three different groups: 1) negative control group (NCG; n = 5): not vaccinated, not infected, 2) positive control group (PCG; n = 20): not vaccinated, infected, and 3) vaccination group (VG; n = 20): single vaccination with an inactivated whole-cell M. hyopneumoniae vaccine (Hyogen®, Ceva) (D1), infected. The PCG and VG were endotracheally inoculated with 7 × 107 CCU in 7 ml of the highly virulent M. hyopneumoniae strain F7.2C (D24) and 7 × 107 CCU in 7 ml low virulent strain F1.12A (D25). A respiratory disease score (RDS) was assessed from D24 until D53. At D53 (euthanasia), macroscopic lung lesions (MLL) were scored, log copies of M. hyopneumoniae DNA (qPCR) and IL-1 and IL-6-concentrations (ELISA) on bronchoalveolar lavage fluid were determined. Results The RDS and MLL at euthanasia were respectively 0, 1.20 and 0.55 (P < 0.001) and 0, 7.56 and 0.68 (P < 0.001) for NCG, PCG and VG, respectively. The qPCR results for PCG and VG were 3.99 and 1.78 log copies (P < 0.001), respectively, with a significant difference between PCG and VG. The IL-1 and IL-6 results at euthanasia for NCG, PCG and VG were 17.61, 1283.39 and 53.04 pg/ml (P < 0.001) and 148.10, 493.35 and 259.80 pg/ml (P = 0.004), respectively with a significant difference between PCG and VG. Conclusions Vaccination with Hyogen® in pigs was efficacious against an experimental challenge with both a low and highly virulent M. hyopneumoniae strain as the vaccinated pigs coughed significantly less, and showed significantly less lung lesions compared to the non-vaccinated challenged pigs: the vaccinated animals showed a 52.9% lower RDS and 91.0% lower MLL compared to the PCG. In the bronchoalveolar lavage fluid collected at the necropsy of the vaccinated pigs, a significantly lower amount of M. hyopneumoniae-DNA and a significantly lower IL-1 and IL-6 concentration was found compared to the pigs of the PCG.
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Affiliation(s)
- Annelies Michiels
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - Ioannis Arsenakis
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Filip Boyen
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | | | - Freddy Haesebrouck
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Dominiek Maes
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
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Takeuti KL, de Barcellos DESN, de Andrade CP, de Almeida LL, Pieters M. Infection dynamics and genetic variability of Mycoplasma hyopneumoniae in self-replacement gilts. Vet Microbiol 2017; 208:18-24. [PMID: 28888635 DOI: 10.1016/j.vetmic.2017.07.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 07/01/2017] [Accepted: 07/06/2017] [Indexed: 11/18/2022]
Abstract
The aim of this study was to assess the longitudinal pattern of M. hyopneumoniae detection in self-replacement gilts at various farms and to characterize the genetic diversity among samples. A total of 298 gilts from three M. hyopneumoniae positive farms were selected at 150days of age (doa). Gilts were tested for M. hyopneumoniae antibodies by ELISA, once in serum at 150 doa and for M. hyopneumoniae detection in laryngeal swabs by real time PCR two or three times. Also, 425 piglets were tested for M. hyopneumoniae detection in laryngeal swabs. A total of 103 samples were characterized by Multiple Locus Variable-number tandem repeats Analysis. Multiple comparison tests were performed and adjusted using Bonferroni correction to compare prevalences of positive gilts by ELISA and real time PCR. Moderate to high prevalence of M. hyopneumoniae in gilts was detected at 150 doa, which decreased over time, and different detection patterns were observed among farms. Dam-to-piglet transmission of M. hyopneumoniae was not detected. The characterization of M. hyopneumoniae showed 17 different variants in all farms, with two identical variants detected in two of the farms. ELISA testing showed high prevalence of seropositive gilts at 150 doa in all farms. Results of this study showed that circulation of M. hyopneumoniae in self-replacement gilts varied among farms, even under similar production and management conditions. In addition, the molecular variability of M. hyopneumoniae detected within farms suggests that in cases of minimal replacement gilt introduction bacterial diversity maybe farm specific.
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Affiliation(s)
- Karine L Takeuti
- Department of Animal Medicine, College of Veterinary Medicine, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil; Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, United States
| | - David E S N de Barcellos
- Department of Animal Medicine, College of Veterinary Medicine, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Caroline P de Andrade
- Department of Animal Medicine, College of Veterinary Medicine, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Laura L de Almeida
- Virology Laboratory, Institute of Veterinary Researches Desidério Finamor, Eldorado do Sul, RS, Brazil
| | - Maria Pieters
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, United States.
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Arsenakis I, Michiels A, Del Pozo Sacristán R, Boyen F, Haesebrouck F, Maes D. Mycoplasma hyopneumoniae vaccination at or shortly before weaning under field conditions: a randomised efficacy trial. Vet Rec 2017; 181:19. [PMID: 28601840 DOI: 10.1136/vr.104075] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/23/2017] [Indexed: 11/03/2022]
Abstract
This study assessed the efficacy of two different Mycoplasma hyopneumoniae vaccination programmes in relation to the time of weaning. Eight hundred and twenty-eight piglets were randomly divided into three groups: group V1 was vaccinated three days before weaning, group V2 at weaning (21 days of age) and group NV was left non-vaccinated. Vaccinations were performed using Ingelvac MycoFLEX. After the nursery period, 306 pigs were allocated to fattening unit (F1) and 501 pigs to a second unit (F2). Efficacy was evaluated using performance parameters and pneumonia lesions at slaughter. Statistically significant differences were obtained in F2 where group V1 had a higher average daily weight gain compared to groups V2 and NV for the entire study period (17 and 18 g/day, respectively) and the fattening period (26 and 36 g/day, respectively) (P<0.05). Considering respiratory disease scores for both fattening units, group V1 was the only group where coughing severity did not increase significantly between placement and the end of the fattening period (P>0.05). Between groups, there were no statistically significant differences for the average lung lesion scores (V1=3.44; V2=4.61; NV=4.55, P>0.05) and the prevalence of pneumonia (V1=35.0 per cent; V2=38.0 per cent; NV=41.4 per cent, P>0.05). Overall, vaccination against M hyopneumoniae before weaning provided numerically better performance than vaccination at weaning, but did not reach statistical significance. An influenza outbreak in F1 and the presence of coexisting mixed respiratory infections in both F1 and F2 could have possibly influenced the performance of both vaccinated groups across all measured parameters.
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Affiliation(s)
- I Arsenakis
- Unit Porcine Health Management, Department of Reproduction, Obstetrics & Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke 9820, Belgium
| | - A Michiels
- Unit Porcine Health Management, Department of Reproduction, Obstetrics & Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke 9820, Belgium
| | - R Del Pozo Sacristán
- Unit Porcine Health Management, Department of Reproduction, Obstetrics & Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke 9820, Belgium
| | - F Boyen
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke 9820, Belgium
| | - F Haesebrouck
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke 9820, Belgium
| | - D Maes
- Unit Porcine Health Management, Department of Reproduction, Obstetrics & Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke 9820, Belgium
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Tassis PD, Tsakmakidis I, Papatsiros VG, Koulialis D, Nell T, Brellou G, Tzika ED. A randomized controlled study on the efficacy of a novel combination vaccine against enzootic pneumonia (Mycoplasma hyopneumoniae) and porcine Circovirus type 2 (PCV2) in the presence of strong maternally derived PCV2 immunity in pigs. BMC Vet Res 2017; 13:91. [PMID: 28388953 PMCID: PMC5384188 DOI: 10.1186/s12917-017-1014-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 03/30/2017] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Mycoplasma hyopneumoniae (M. hyo) and Porcine Circovirus Type 2 (PCV2) are major pathogens that cause significant health problems in swine worldwide. Maternal derived immunity (MDI) has been suggested as a significant immediate defence factor for newborn piglets and may interfere with piglet's vaccination-induced immunity. The study aimed to assess the efficacy of a novel combination vaccine (consisting of PCV2 subunits and inactivated M. hyo strain J), against PCV2 and M. hyo natural infection [Porcilis® PCV M Hyo (MSD Animal Health, Boxmeer, the Netherlands)], in the presence of strong maternally derived PCV2 immunity (antibody titre averaged 11.08 log2), under field conditions. The study was performed according to a controlled, randomized and blinded design in a Greek swine unit with Enzootic Pneumonia (EP) and subclinical PCV2 infection. In total, 600 healthy three-week-old suckling piglets were allocated randomly, either to treatment (vaccinated with the test product) or control group (injected with sterile buffered saline). RESULTS Vaccination significantly reduced the severity of lung lesions at slaughter (lesions of cranio-ventral pulmonary consolidation) (P < 0.001). The overall mean lung lesion score (LLS) was 9.6 in the vaccinated group and 12.2 in controls. The level of PCV2 viraemia was significantly reduced in vaccinated pigs. Furthermore, 25 g higher average daily weight gain (ADWG) was observed during the finishing phase (P < 0.001) and 18 g greater ADWG overall (P < 0.001). CONCLUSIONS Results of LLS, PCV2 viremia and ADWG support the test product's efficacy in the face of strong maternally derived PCV2 immunity.
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Affiliation(s)
- Panagiotis D Tassis
- Farm Animals Clinic, School of Veterinary Medicine, Aristotle University of Thessaloniki, St. Voutyra 11, 54627, Thessaloniki, Greece.
| | - Ioannis Tsakmakidis
- Farm Animals Clinic, School of Veterinary Medicine, Aristotle University of Thessaloniki, St. Voutyra 11, 54627, Thessaloniki, Greece
| | - Vassileios G Papatsiros
- Clinic of Medicine, Faculty of Veterinary Science, University of Thessaly, P.O. Box 199, Trikalon 224, Karditsa, Greece
| | - Dimitrios Koulialis
- Farm Animals Clinic, School of Veterinary Medicine, Aristotle University of Thessaloniki, St. Voutyra 11, 54627, Thessaloniki, Greece
| | - Tom Nell
- Animal Health, Clinical Study Team Biologicals, P.O. Box 31, Boxmeer, 5830 AA, the Netherlands
| | - Georgia Brellou
- Laboratory of Pathology, School of Veterinary Medicine, Aristotle University of Thessaloniki, University Campus, 54124, Thessaloniki, Greece
| | - Eleni D Tzika
- Farm Animals Clinic, School of Veterinary Medicine, Aristotle University of Thessaloniki, St. Voutyra 11, 54627, Thessaloniki, Greece
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Arsenakis I, Panzavolta L, Michiels A, Del Pozo Sacristán R, Boyen F, Haesebrouck F, Maes D. Efficacy of Mycoplasma hyopneumoniae vaccination before and at weaning against experimental challenge infection in pigs. BMC Vet Res 2016; 12:63. [PMID: 27025924 PMCID: PMC4812620 DOI: 10.1186/s12917-016-0685-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 03/17/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Commercial bacterins are widely used at weaning to control Mycoplasma hyopneumoniae infections in pigs. However, it is not known whether the efficacy of vaccinating against M. hyopneumoniae can be influenced by the weaning process when vaccination is applied at the day of weaning. The present study assessed the efficacy of a single M. hyopneumoniae vaccination (Ingelvac MycoFLEX®) three days before weaning (V1) or at weaning (V2) against experimental challenge infection. Four weeks after vaccination, groups V1 and V2 (n = 20 pigs each) and a non-vaccinated, positive control group (PCG) (n = 20) were endotracheally inoculated with a virulent M. hyopneumoniae field strain. Five pigs were used as a negative control group. All pigs were euthanized 5 weeks after challenge. The main parameters investigated included macroscopic and histopathological lung lesions at necropsy, immunofluorescence (IF) staining and quantitative real-time PCR (qPCR) on broncho-alveolar lavage (BAL) fluid for quantifying M. hyopneumoniae. RESULTS The average macroscopic lung lesion scores in groups V1, V2 and PCG were 0.54, 0.88 and 1.04, respectively (P > 0.05). The average lymphohistiocytic infiltration scores in groups V1, V2 and PCG were 2.95, 3.16 and 3.61, respectively (P < 0.05). The average IF scores were: V1 = 1.13, V2 = 1.19 and PCG = 1.25 (P > 0.05), the qPCR values were: V1 = 10(2.94), V2 = 10(2.76) and PCG = 10(3.23) (P > 0.05). All pigs of the negative control group remained negative throughout the study. CONCLUSIONS Both vaccinated groups had lower numbers of macroscopic and histopathological lung lesions, and lower numbers of M. hyopneumoniae organisms in the BAL fluid compared to the PCG. However, no firm conclusions could be made on whether weaning negatively influences the efficacy of M. hyopneumoniae vaccination, since significant differences between the treatment groups were only obtained for the histopathological lung lesions. This could be attributed to the fact that milder macroscopic lung lesions were produced in the inoculated pigs, when compared to previous trials conducted by the same group. Further research under field conditions is warranted to assess possible differences between the two vaccination strategies.
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Affiliation(s)
- Ioannis Arsenakis
- Porcine Health Management Unit, Department of Reproduction, Obstetrics & Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium.
| | - Luca Panzavolta
- Porcine Health Management Unit, Department of Reproduction, Obstetrics & Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium
| | - Annelies Michiels
- Porcine Health Management Unit, Department of Reproduction, Obstetrics & Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium
| | - Rubén Del Pozo Sacristán
- Porcine Health Management Unit, Department of Reproduction, Obstetrics & Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium
| | - Filip Boyen
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium
| | - Freddy Haesebrouck
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium
| | - Dominiek Maes
- Porcine Health Management Unit, Department of Reproduction, Obstetrics & Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium
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Fisch A, Marchioro SB, Gomes CK, Galli V, de Oliveira NR, Simionatto S, Dellagostin OA, Mendonça M, Moreira ÂN, Conceição FR. Commercial bacterins did not induce detectable levels of antibodies in mice against Mycoplasma hyopneumoniae antigens strongly recognized by swine immune system. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.trivac.2016.01.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Batista Linhares M, Belloy L, Origgi FC, Lechner I, Segner H, Ryser-Degiorgis MP. Investigating the role of free-ranging wild boar (Sus scrofa) in the re-emergence of enzootic pneumonia in domestic pig herds: a pathological, prevalence and risk-factor study. PLoS One 2015; 10:e0119060. [PMID: 25747151 PMCID: PMC4352045 DOI: 10.1371/journal.pone.0119060] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 01/09/2015] [Indexed: 11/28/2022] Open
Abstract
Enzootic pneumonia (EP) caused by Mycoplasma hyopneumoniae has a significant economic impact on domestic pig production. A control program carried out from 1999 to 2003 successfully reduced disease occurrence in domestic pigs in Switzerland, but recurrent outbreaks suggested a potential role of free-ranging wild boar (Sus scrofa) as a source of re-infection. Since little is known on the epidemiology of EP in wild boar populations, our aims were: (1) to estimate the prevalence of M. hyopneumoniae infections in wild boar in Switzerland; (2) to identify risk factors for infection in wild boar; and (3) to assess whether infection in wild boar is associated with the same gross and microscopic lesions typical of EP in domestic pigs. Nasal swabs, bronchial swabs and lung samples were collected from 978 wild boar from five study areas in Switzerland between October 2011 and May 2013. Swabs were analyzed by qualitative real time PCR and a histopathological study was conducted on lung tissues. Risk factor analysis was performed using multivariable logistic regression modeling. Overall prevalence in nasal swabs was 26.2% (95% CI 23.3–29.3%) but significant geographical differences were observed. Wild boar density, occurrence of EP outbreaks in domestic pigs and young age were identified as risk factors for infection. There was a significant association between infection and lesions consistent with EP in domestic pigs. We have concluded that M. hyopneumoniae is widespread in the Swiss wild boar population, that the same risk factors for infection of domestic pigs also act as risk factors for infection of wild boar, and that infected wild boar develop lesions similar to those found in domestic pigs. However, based on our data and the outbreak pattern in domestic pigs, we propose that spillover from domestic pigs to wild boar is more likely than transmission from wild boar to pigs.
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Affiliation(s)
- Mainity Batista Linhares
- Centre for Fish and Wildlife Health (FIWI), Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Luc Belloy
- Institut Galli-Valerio, Laboratoire d’Analyses vétérinaires, Département du Territoire et de l’Environnement, Lausanne, Switzerland
| | - Francesco C. Origgi
- Centre for Fish and Wildlife Health (FIWI), Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Isabel Lechner
- Veterinary Public Health Institute, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Helmut Segner
- Centre for Fish and Wildlife Health (FIWI), Vetsuisse Faculty, University of Bern, Bern, Switzerland
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Animal and management factors influencing grower and finisher pig performance and efficiency in European systems: a meta-analysis. Animal 2015; 9:1210-20. [PMID: 25737212 DOI: 10.1017/s1751731115000269] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
A meta-analysis on the effects of management and animal-based factors on the performance and feed efficiency of growing pigs can provide information on single factor and interaction effects absent in individual studies. This study analysed the effects of such factors on average daily gain (ADG), feed intake (FI) and feed conversion ratio (FCR) of grower and finisher pigs. The multivariate models identified significant effects of: (1) bedding (P<0.01), stage of growth (P<0.001) and the interaction bedding×lysine (P<0.001) on ADG. ADG was higher on straw compared with no bedding (710 v. 605 g/day). (2) FI was significantly affected by stage of growth (P<0.01), bedding (P<0.01), group composition (P<0.05), group size (P<0.01), feed CP content (P<0.01), ambient temperature (P<0.01) and the interaction between floor space and feed energy content (P<0.001). Pigs housed on straw had a lower FI in comparison with those without (1.44 v. 2.04 kg/day); a higher FI was seen for pigs separated by gender in comparison with mixed groups (2.05 v. 1.65 kg/day); FI had a negative linear relationship with group size, the CP content of the feed and ambient temperature. (3) Stage of growth (P<0.001), feed CP (P<0.001) and lysine content (P<0.001), ambient temperature (P<0.001) and feed crude fibre (CF) content (P<0.01) significantly affected FCR; there were no significant interactions between any factors on this trait. There was an improvement in FCR at higher ambient temperatures, increased feed CP and lysine content, but a deterioration of FCR at higher CF contents. For ADG, the interaction of bedding×lysine was caused by pigs housed without bedding (straw) having higher ADG when on a feed lower in lysine, whereas those with bedding had a higher ADG when on a feed higher in lysine. Interaction effects on FI were caused by animals with the least amount of floor space having a higher FI when given a feed with a low metabolisable energy (ME) content, in contrast to all other pigs, which showed a higher FI with increased ME content. The meta-analysis confirmed the significant effect of several well-known factors on the performance and efficiency of grower and finisher pigs, the effects of some less established ones and, importantly, the interactions between such factors.
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Effect of various husbandry conditions on the production parameters of swine herds in Poland. Pol J Vet Sci 2014; 16:707-13. [PMID: 24597306 DOI: 10.2478/pjvs-2013-0100] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The aim of this study was to collect production data of Polish swine herds, with special emphasis on the production parameters in farrow to finish pig herds. Another goal was to determine differences in the production performance of swine herds with different sizes, various status with regard to biosecurity, and with different veterinary expenditure. For this purpose, questionnaire surveys were carried out in 96 polish farrow to finish pig herds. The data concerning production parameters (e.g. the number of pigs born per sow per year, litters per sow per year, pre- and post-weaning mortality), farm size (small, medium, large), management (all in-all out by room or building), veterinary expenditure (including medication) and the percentage of pigs under medical treatment, were collected. The data obtained in the present study indicate that in general, the efficiency of swine production in evaluated farms was relatively low. It was also found that in large swine farms the efficiency was better than that in small ones and that the proper biosecurity positively influenced the performance of the swine farms. However, only in 10.4% facilities, the biosecurity rules and methods, including the principle "all-in all-out", were implemented and kept. It seems that inefficient swine production on the majority of Polish farms results from poor basic knowledge on pig production and understanding of fundamental economic rules of swine breeding.
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Hillen S, von Berg S, Köhler K, Reinacher M, Willems H, Reiner G. Occurrence and severity of lung lesions in slaughter pigs vaccinated against Mycoplasma hyopneumoniae with different strategies. Prev Vet Med 2014; 113:580-8. [DOI: 10.1016/j.prevetmed.2013.12.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2013] [Revised: 12/20/2013] [Accepted: 12/23/2013] [Indexed: 10/25/2022]
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Maglennon GA, Cook BS, Deeney AS, Bossé JT, Peters SE, Langford PR, Maskell DJ, Tucker AW, Wren BW, Rycroft AN. Transposon mutagenesis in Mycoplasma hyopneumoniae using a novel mariner-based system for generating random mutations. Vet Res 2013; 44:124. [PMID: 24359443 PMCID: PMC4028751 DOI: 10.1186/1297-9716-44-124] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 12/02/2013] [Indexed: 11/10/2022] Open
Abstract
Mycoplasma hyopneumoniae is the cause of enzootic pneumonia in pigs, a chronic respiratory disease associated with significant economic losses to swine producers worldwide. The molecular pathogenesis of infection is poorly understood due to the lack of genetic tools to allow manipulation of the organism and more generally for the Mycoplasma genus. The objective of this study was to develop a system for generating random transposon insertion mutants in M. hyopneumoniae that could prove a powerful tool in enabling the pathogenesis of infection to be unraveled. A novel delivery vector was constructed containing a hyperactive C9 mutant of the Himar1 transposase along with a mini transposon containing the tetracycline resistance cassette, tetM. M. hyopneumoniae strain 232 was electroporated with the construct and tetM-expressing transformants selected on agar containing tetracycline. Individual transformants contained single transposon insertions that were stable upon serial passages in broth medium. The insertion sites of 44 individual transformants were determined and confirmed disruption of several M. hyopneumoniae genes. A large pool of over 10 000 mutants was generated that should allow saturation of the M. hyopneumoniae strain 232 genome. This is the first time that transposon mutagenesis has been demonstrated in this important pathogen and could be generally applied for other Mycoplasma species that are intractable to genetic manipulation. The ability to generate random mutant libraries is a powerful tool in the further study of the pathogenesis of this important swine pathogen.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Andrew N Rycroft
- Department of Pathology and Pathogen Biology, The Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, AL9 7TA, UK.
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Kukushkin S, Okovytaya T. Seroprevalence of
Lawsonia intracellularis, Mycoplasma hyopneumoniae
and PCV2 in commercial pig farms in Russia. VETERINARY RECORD CASE REPORTS 2013. [DOI: 10.1136/vetreccr.100874rep] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- S. Kukushkin
- Department of Animal HealthBoehringer Ingelheim LLCLeningradskoye shosse, 16A, building 3Moscow125171Russia
| | - T. Okovytaya
- Laboratory of Enzymoimmunoassay and Serological Diagnostics for Infectious Animal DiseasesInstitute for Biotechnologies of Veterinary MedicineVolginskiy Village, Petushinskiy AreaVladimirskaya Oblast601125Russia
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Simionatto S, Marchioro SB, Maes D, Dellagostin OA. Mycoplasma hyopneumoniae: from disease to vaccine development. Vet Microbiol 2013; 165:234-42. [PMID: 23680109 DOI: 10.1016/j.vetmic.2013.04.019] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 04/15/2013] [Accepted: 04/16/2013] [Indexed: 02/02/2023]
Abstract
Mycoplasma hyopneumoniae is the etiological agent of swine enzootic pneumonia (EP), a disease that affects swine production worldwide. Vaccination is the most cost-effective strategy for the control and prevention of the disease. Despite efforts to control M. hyopneumoniae infection, significant economic losses in pig production continue to occur. The results of genome-based research have the potential to help understand the biology and pathogenesis of M. hyopneumoniae, and contribute to the development of more effective vaccines and diagnostic tests. In this review, the characteristics of M. hyopneumoniae related to pathogenesis and control measures will be discussed. Special emphasis will be placed on vaccination strategies that have been proposed with the use of reverse vaccinology approaches.
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Affiliation(s)
- Simone Simionatto
- Núcleo de Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, RS, Brazil.
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Nathues H, Chang YM, Wieland B, Rechter G, Spergser J, Rosengarten R, Kreienbrock L, grosse Beilage E. Herd-Level Risk Factors for the Seropositivity toMycoplasma hyopneumoniaeand the Occurrence of Enzootic Pneumonia Among Fattening Pigs in Areas of Endemic Infection and High Pig Density. Transbound Emerg Dis 2012. [DOI: 10.1111/tbed.12033] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- H. Nathues
- Field Station for Epidemiology; University of Veterinary Medicine Hannover, Foundation; Bakum Germany
- Veterinary Epidemiology and Public Health Group; The Royal Veterinary College; Hatfield Hertfordshire UK
| | - Y. M. Chang
- Veterinary Epidemiology and Public Health Group; The Royal Veterinary College; Hatfield Hertfordshire UK
| | - B. Wieland
- Veterinary Epidemiology and Public Health Group; The Royal Veterinary College; Hatfield Hertfordshire UK
| | - G. Rechter
- Institute for Biometry, Epidemiology & Information Processing; WHO Collaborating Centre for Research and Training in Veterinary Public Health; University of Veterinary Medicine Hannover, Foundation; Hannover Germany
| | - J. Spergser
- Department of Pathobiology; Institute of Bacteriology, Mycology and Hygiene; University of Veterinary Medicine; Vienna Austria
| | - R. Rosengarten
- Department of Pathobiology; Institute of Bacteriology, Mycology and Hygiene; University of Veterinary Medicine; Vienna Austria
| | - L. Kreienbrock
- Institute for Biometry, Epidemiology & Information Processing; WHO Collaborating Centre for Research and Training in Veterinary Public Health; University of Veterinary Medicine Hannover, Foundation; Hannover Germany
| | - E. grosse Beilage
- Field Station for Epidemiology; University of Veterinary Medicine Hannover, Foundation; Bakum Germany
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Del Pozo Sacristán R, Rodríguez AL, Sierens A, Vranckx K, Boyen F, Dereu A, Haesebrouck F, Maes DGD. Efficacy of in-feed medication with chlortetracycline in a farrow-to-finish herd against a clinical outbreak of respiratory disease in fattening pigs. Vet Rec 2012; 171:645. [PMID: 23136309 DOI: 10.1136/vr.100976] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The efficacy of chlortetracycline (CTC) in-feed medication to treat pigs with clinical respiratory disease was investigated in a farrow-to-finish pig herd infected with Mycoplasma hyopneumoniae, and with clinical respiratory disease in growing pigs. In total, 533 pigs were included. The animals were vaccinated against M hyopneumoniae and porcine circovirus type 2 at weaning. At onset of clinical respiratory disease, they were randomly allocated to one of the following treatment groups: chlortetracycline 1 (CTC1) (two consecutive weeks, 500 ppm), chlortetracycline 2 (CTC2) (two non-consecutive weeks, with a non-medicated week interval in between, 500 ppm) or tylosin (T) (three consecutive weeks, 100 ppm). Performance (daily weight gain, feed conversion ratio), pneumonia lesions at slaughter and clinical parameters (respiratory disease score) were assessed. Only numeric differences in favour of the CTC2 group were obtained for the performance and the clinical parameters. The prevalence of pneumonia lesions was 20.5, 13.1 and 23.0 per cent (P<0.05) for the CTC1, CTC2 and T groups, respectively. The study demonstrated that CTC, when administered at onset of clinical respiratory disease via the feed at a dose of 500 ppm during two alternative weeks, was able to decrease the prevalence of pneumonia lesions, and numerically reduce performance losses and clinical signs.
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Affiliation(s)
- R Del Pozo Sacristán
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke B-9820, Belgium.
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Vaccination of piglets at 1 week of age with an inactivated Mycoplasma hyopneumoniae vaccine reduces lung lesions and improves average daily gain in body weight. Vaccine 2012; 30:7625-9. [PMID: 23084853 DOI: 10.1016/j.vaccine.2012.10.028] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 09/24/2012] [Accepted: 10/05/2012] [Indexed: 11/21/2022]
Abstract
The field efficacy and safety of a single-dose inactivated Mycoplasma hyopneumoniae vaccine, Suvaxyn MH-One, was evaluated in 4-5-day-old piglets on a commercial farm with a history of Mycoplasma disease in Southern Germany. The piglets were injected intramuscularly with the vaccine or saline (control group) and raised under commercial conditions to slaughter weight. The efficacy of the vaccine was determined by comparing the lung lesions associated with infection by M. hyopneumoniae in control and vaccinated pigs post mortem. In this analysis the vaccinated pigs had the lower mean percentage lung lesion at 5% compared to 9% in controls. Of the vaccinated pigs 52.3% were shown to have low levels of lung lesions between 0% and 5% and no more than 5.4% were shown to have levels above 20%. In contrast, the pigs administered saline showed 36.5% in the lower category (0-5%), while 18.3% showed lesions greater than 20%. There were significant differences in the mean body weight of pigs at the final two weight measurements at approximately 21 weeks and 26 weeks of age, with those receiving Suvaxyn MH-One being on average 5 kg heavier at each time point. There was also a significant increase in average daily gain in the vaccinated animals compared to the control group, particularly in the period from vaccination to the final two body weight measurements on day 138 and 166, from weaning at day 28 to the final two body measurements and from mid-way during finishing at day 84 to the final two body weight measurements. Vaccination had no adverse impact on appetite, although small numbers of vaccinated and control pigs did show mild signs of coughing, sneezing, respiratory distress or depression. There was no adverse impact on rectal temperatures and no signs of injection site reactions during the course of the study. We can conclude that vaccination with Suvaxyn MH-One to pigs at less than 1 week of age is effective in reducing lung lesions resulting from M. hyopneumoniae and also aids growth performance by reducing weight losses and improving average daily gain.
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Kukushkin S, Okovytaya T. Seroprevalence of Lawsonia intracellularis, Mycoplasma hyopneumoniae and PCV2 in commercial pig farms in Russia. Vet Rec 2012; 171:126. [PMID: 22791518 DOI: 10.1136/vr.100874] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- S Kukushkin
- Department of Animal Health, Boehringer Ingelheim LLC, Leningradskoye shosse, 16A, building 3, Moscow 125171, Russia.
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Vranckx K, Maes D, Marchioro SB, Villarreal I, Chiers K, Pasmans F, Haesebrouck F. Vaccination reduces macrophage infiltration in bronchus-associated lymphoid tissue in pigs infected with a highly virulent Mycoplasma hyopneumoniae strain. BMC Vet Res 2012; 8:24. [PMID: 22409839 PMCID: PMC3349615 DOI: 10.1186/1746-6148-8-24] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2011] [Accepted: 03/12/2012] [Indexed: 11/26/2022] Open
Abstract
Background Mycoplasma hyopneumoniae is the causative agent of enzootic pneumonia and is responsible for significant economic losses to the pig industry. To better understand the mode of action of a commercial, adjuvanted, inactivated whole cell vaccine and the influence of diversity on the efficacy of vaccination, we investigated samples from vaccinated and non-vaccinated pigs experimentally infected with either a low (LV) or a highly virulent (HV) M. hyopneumoniae strain. Non-vaccinated and sham-infected control groups were included. Lung tissue samples collected at 4 and 8 weeks post infection (PI) were immunohistochemically tested for the presence of T-lymphocytes, B-lymphocytes and macrophages in the bronchus-associated lymphoid tissue (BALT). The number of M. hyopneumoniae organisms in bronchoalveolar lavage (BAL) fluid was determined using quantitative PCR at 4 and 8 weeks PI. Serum antibodies against M. hyopneumoniae were determined at 0, 2, 4, 6 and 8 weeks PI. Results The immunostaining revealed a lower density of macrophages in the BALT of the vaccinated groups compared to the non-vaccinated groups. The highest number of M. hyopneumoniae organisms in the BAL fluid was measured at 4 weeks PI for the HV strain and at 8 weeks PI for the LV strain. Vaccination reduced the number of organisms non-significantly, though for the HV strain the reduction was clinically more relevant than for the LV strain. At the level of the individual pigs, a higher lung lesion score was associated with more M. hyopneumoniae organisms in the lungs and a higher density of the investigated immune cells in the BALT. Conclusions In conclusion, the infiltration of macrophages after infection with M. hyopneumoniae is reduced by vaccination. The M. hyopneumoniae replication in the lungs is also reduced in vaccinated pigs, though the HV strain is inhibited more than the LV strain.
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Affiliation(s)
- Katleen Vranckx
- Department of Pathology, Bacteriology and Avian Diseases, Ghent University, Faculty of Veterinary Medicine, Salisburylaan 133, B-9820 Merelbeke, Belgium.
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BPEX Pig Health Scheme: a useful monitoring system for respiratory disease control in pig farms? BMC Vet Res 2011; 7:82. [PMID: 22208847 PMCID: PMC3285094 DOI: 10.1186/1746-6148-7-82] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Accepted: 12/30/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Respiratory diseases account for significant economic losses to the UK pig industry. Lesions indicative of respiratory disease in pig lungs at slaughter e.g. pneumonia and pleuritis are frequently recorded to assess herd health or provide data for epidemiological studies. The BPEX Pig Health Scheme (BPHS) is a monitoring system, which informs producers of gross lesions in their pigs' carcasses at slaughter, enabling farm-level decisions to be made. The aim of the study was to assess whether information provided by the BPHS regarding respiratory lesions was associated with respiratory pathogens in the farm, farm management practices and each other. RESULTS BPHS reports were obtained from a subset of 70 pig farms involved in a cross-sectional study conducted in 2008-09 investigating the epidemiology of post-weaning multi-systemic wasting syndrome. The reports were combined with data regarding the presence/absence of several pathogens in the herd and potential farm-level risk factors for respiratory disease. Principal component analysis (PCA) performed on BPHS reports generated three principal components, explaining 71% of the total variance. Enzootic pneumonia score, severe pleurisy and acute pleuropneumonia had the highest loadings for the principal component which explained the largest percentage of the total variance (35%) (BPHS component 1), it was thought that this component identifies farms with acute disease. Using the factor loadings a score for each farm for BPHS component 1 was obtained. As farms' score for BPHS component 1 increased, average carcass weight at slaughter decreased. In addition, farms positive for H1N2 and porcine reproductive and respiratory disease virus (PRRSV) were more likely to have higher levels of severe and mild pleurisy reported by the BPHS, respectively. CONCLUSIONS The study found statistical associations between levels of pleurisy recorded by BPHS at slaughter and the presence H1N2 and PRRSV in the herd. There is also some evidence that farms which submit pigs with these lesions may have reduced productivity. However, more research is needed to fully validate the scheme.
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40
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Fablet C, Marois-Créhan C, Simon G, Grasland B, Jestin A, Kobisch M, Madec F, Rose N. Infectious agents associated with respiratory diseases in 125 farrow-to-finish pig herds: a cross-sectional study. Vet Microbiol 2011; 157:152-63. [PMID: 22226820 DOI: 10.1016/j.vetmic.2011.12.015] [Citation(s) in RCA: 108] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Revised: 11/07/2011] [Accepted: 12/12/2011] [Indexed: 11/17/2022]
Abstract
A study was carried out in 125 farrow-to-finish pig herds to assess the relationships between pathogens involved in respiratory disorders and to relate these findings to clinical signs of respiratory diseases and pneumonia and pleuritis at slaughter. Clinical examination and sampling were carried out on four different batches in each herd (pigs aged 4, 10, 16 and 22 weeks). Mycoplasma hyopneumoniae, Actinobacillus pleuropneumoniae, swine influenza viruses (SIV), porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus type 2 (PCV2) were detected by serological or PCR tests. Pneumonia-like gross lesions and pleuritis were scored at the slaughterhouse. The results indicate that the percentage of pigs PCR-positive for PCV2 at 4, 10 and 16 weeks old was associated with the percentage of pigs PCR-positive for M. hyopneumoniae at these ages. On the other hand, the percentage of pigs with antibodies against PRRSV at 10, 16 and 22 weeks was positively correlated with the percentage of pigs seropositive for M. hyopneumoniae at 22 weeks, with the percentage of pigs with antibodies against SIV H1N1 and SIV H1N2 and the percentage of pigs sero-positive for A. pleuropneumoniae serotype 2. The findings also indicate that, within the five studied pathogens, M. hyopneumoniae, PRRSV and SIV H1N1 are the major pathogens involved in pneumonia-like gross lesions even though PCV2 may play a role. A. pleuropneumoniae serotype 2, in association with PRRSV, is significantly associated with extensive pleuritis. Respiratory diseases could be significantly reduced by implementing measures including appropriate management practices to control these pathogens.
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Affiliation(s)
- C Fablet
- Agence Nationale de Sécurité Sanitaire (Anses), Unité Epidémiologie et Bien-Etre du Porc, B.P. 53, 22440 Ploufragan, France.
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41
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Chae C. Vaccinating pigs against Mycoplasma hyopneumoniae infection: Failure to prevent transmission. Vet J 2011; 188:7-8. [DOI: 10.1016/j.tvjl.2010.05.032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Accepted: 05/26/2010] [Indexed: 10/19/2022]
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Heinonen M, Laurila T, Vidgren G, Levonen K. Eradication of Mycoplasma hyopneumoniae from a swine finishing herd without total depopulation. Vet J 2011; 188:110-4. [DOI: 10.1016/j.tvjl.2010.02.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Revised: 02/16/2010] [Accepted: 02/17/2010] [Indexed: 12/01/2022]
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The effect of vaccination on the transmission of Mycoplasma hyopneumoniae in pigs under field conditions. Vet J 2011; 188:48-52. [DOI: 10.1016/j.tvjl.2010.04.024] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Revised: 04/19/2010] [Accepted: 04/21/2010] [Indexed: 11/23/2022]
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Effect of vaccination of pigs against experimental infection with high and low virulence Mycoplasma hyopneumoniae strains. Vaccine 2011; 29:1731-5. [PMID: 21237277 DOI: 10.1016/j.vaccine.2011.01.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Revised: 12/23/2010] [Accepted: 01/05/2011] [Indexed: 11/21/2022]
Abstract
This study investigated the infection pattern and lung lesion development in pigs caused by a low and highly virulent Mycoplasma hyopneumoniae strain at 4 and 8 weeks (w) post infection (PI). It also determined the efficacy of a commercial inactivated whole-cell vaccine against infection with each one of these M. hyopneumoniae strains. Ninety piglets free of M. hyopneumoniae were selected, and 40 of them were randomly vaccinated during their first week of life. At weaning, all piglets were allocated to 10 different groups and housed in pens with absolute filters. At 4 weeks of age, pigs were inoculated intratracheally with either a highly virulent M. hyopneumoniae strain, a low virulent strain or with sterile culture medium. Half of all animals were euthanized at 4 w PI, while the remaining half was euthanized at 8 w PI. Coughing was assessed daily, and lung lesions, immunofluorescence (IF), bacteriological analysis and nested PCR were assessed after necropsy. It was demonstrated that contrary to the highly virulent strain, the low virulent strain required more than 4 weeks PI (commonly accepted as the standard infection model) to reach maximum clinical symptoms. Vaccination significantly reduced clinical symptoms, macroscopic and microscopic lung lesions in pigs infected with the highly virulent strain. This effect was more pronounced at 4 than at 8 weeks PI. Protective efficacy was also observed in pigs infected with the low virulent strain, but the effect was less pronounced than on the highly virulent strain.
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Meyns T, Van Steelant J, Rolly E, Dewulf J, Haesebrouck F, Maes D. A cross-sectional study of risk factors associated with pulmonary lesions in pigs at slaughter. Vet J 2010; 187:388-92. [PMID: 20122861 DOI: 10.1016/j.tvjl.2009.12.027] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2008] [Revised: 12/17/2009] [Accepted: 12/23/2009] [Indexed: 11/25/2022]
Abstract
A cross-sectional study was conducted to identify herd-level factors that may influence the prevalence and severity of macroscopically visible pulmonary lesions in pigs at slaughter. Data were collected following abattoir inspection of 50 randomly-selected batches of 6335 pigs and by interviewing the producers. Macroscopic lung lesions were identified and scored semi-quantitatively in ≥ 80 pigs/herd and the prevalence of pleuritis and pneumonia was 20.76% and 23.85%, respectively. Following multivariable analysis, the seroprevalence of Actinobacillus pleuropneumoniae (P < 0.001) and Mycoplasma hyopneumoniae (P = 0.018) and the number of pigs/nursery pen (P = 0.023) were positively associated, whereas average weaning age was negatively associated (P = 0.001) with the pleuritis score. Risk factors associated with a higher prevalence of pneumonia were the presence of pleuritis (P = 0.001) and the frequent purchasing of pigs (P = 0.020). The findings of this study indicate that the prevalence of pleuritis and pneumonia remains high in Belgium and management factors are central to disease control.
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Affiliation(s)
- Tom Meyns
- Department of Bacteriology, Pathology and Poultry Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
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Stakenborg T, Vicca J, Butaye P, Imberechts H, Peeters J, de Kruif A, Haesebrouck F, Maes D. A multiplex PCR to identify porcine mycoplasmas present in broth cultures. Vet Res Commun 2009; 30:239-47. [PMID: 16437299 DOI: 10.1007/s11259-006-3226-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/2004] [Indexed: 11/29/2022]
Abstract
Mycoplasma hyopneumoniae, Mycoplasma hyorhinis and Mycoplasma flocculare can be present in the lungs of pigs at the same time. These three mycoplasma species all require similar growth conditions and can be recovered from clinical samples using the same media. We have developed a multiplex PCR as a helpful tool for rapid differentiation of these three species in the course of isolation. Based on the 16S ribosomal DNA sequences, three different forward primers and a single reverse primer were selected. Each forward primer was compared to available mycoplasma sequences, showing the primers to be specific. The three amplification products observed of 1129 bp (M. hyorhinis), 1000 bp (M. hyopneumoniae) and 754 bp (M. flocculare) were clearly distinguishable on a 1% agarose gel. In addition, no cross-reaction with Mycoplasma hyosynoviae, another porcine mycoplasma, was noted. This multiplex PCR using the proposed set of primers is the first reported assay that allows the simultaneous identification of the different Mycoplasma species isolated from the lungs of pigs.
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Affiliation(s)
- T Stakenborg
- Veterinary and Agrochemical Research Centre, Groeselenberg 99, 1180, Brussels.
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47
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The relationship between infectious and non-infectious herd factors with pneumonia at slaughter and productive parameters in fattening pigs. Vet J 2009; 179:240-6. [DOI: 10.1016/j.tvjl.2007.10.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2007] [Revised: 08/21/2007] [Accepted: 10/01/2007] [Indexed: 11/20/2022]
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Seroprevalence and risk factors associated with seropositivity in sows from 67 herds in north-west Germany infected with Mycoplasma hyopneumoniae. Prev Vet Med 2008; 88:255-63. [PMID: 19101052 DOI: 10.1016/j.prevetmed.2008.10.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2008] [Revised: 10/14/2008] [Accepted: 10/16/2008] [Indexed: 11/21/2022]
Abstract
Risk factors for the spread of Mycoplasma hyopneumoniae in sows have not been studied although vertical transmission from sows to their offspring is considered a significant risk factor in the development of enzootic pneumonia in growers and finishers. Seropositivity for M. hyopneumoniae in sows, as assessed by commercial ELISA, is a possible indicator of infection pressure among sows. The objective of this study was to estimate seroprevalence and associated risk factors of a sow being seropositive for M. hyopneumoniae. A cross-sectional study was carried out in 2578 sows from 67 herds in north-west Germany. Data concerning general herd characteristics, acclimatisation practices, indoor and outside contacts, as well as data describing the immediate local environment were collected during a herd visit via questionnaire. Blood samples were seropositive in 65% of the 2578 sows, and all herds had >/=14% seropositive sows. Data analysis was performed in two steps. First, univariate analysis of predictor variables for the risk of a sow being seropositive for M. hyopneumoniae was performed using chi-square test. Secondly, all variables associated with the risk of a sow being seropositive (P</=0.25) were included in a multivariate model using a generalised linear model. The risk of a sow being seropositive for M. hyopneumoniae was increased in herds with two- or three-site production (OR 1.50), when piglets were not vaccinated against M. hyopneumoniae (OR 1.81), in herds with a 2-week farrowing intervals (OR 1.84) and in herds without all-in/all-out management of the farrowing units (OR 1.37). The lack of an acclimatisation period for replacement boars was also associated with the risk of a sow being seropositive (OR 2.10). The results indicate that M. hyopneumoniae seropositivity is common in sows in north-west Germany and is influenced by various management factors. It is recommended that evaluation of sow herd management should be included in any strategic health plan to control M. hyopneumoniae infection.
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Sibila M, Pieters M, Molitor T, Maes D, Haesebrouck F, Segalés J. Current perspectives on the diagnosis and epidemiology of Mycoplasma hyopneumoniae infection. Vet J 2008; 181:221-31. [PMID: 18396428 PMCID: PMC7110805 DOI: 10.1016/j.tvjl.2008.02.020] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2007] [Revised: 02/13/2008] [Accepted: 02/22/2008] [Indexed: 11/28/2022]
Abstract
Mycoplasma hyopneumoniae is the principal aetiological agent of enzootic pneumonia (EP), a chronic respiratory disease that affects mainly finishing pigs. Although major efforts to control M. hyopneumoniae infection and its detrimental effects have been made, significant economic losses in pig production worldwide due to EP continue. M. hyopneumoniae is typically introduced into pig herds by the purchase of subclinically infected animals or, less frequently, through airborne transmission over short distances. Once in the herd, M. hyopneumoniae may be transmitted by direct contact from infected sows to their offspring or between pen mates. The ‘gold standard’ technique used to diagnose M. hyopneumoniae infection, bacteriological culture, is laborious and is seldom used routinely. Enzyme-linked immunosorbent assay and polymerase chain reaction detection methods, in addition to post-mortem inspection in the form of abattoir surveillance or field necropsy, are the techniques most frequently used to investigate the potential involvement of M. hyopneumoniae in porcine respiratory disease. Such techniques have been used to monitor the incidence of M. hyopneumoniae infection in herds both clinically and subclinically affected by EP, in vaccinated and non-vaccinated herds and under different production and management conditions. Differences in the clinical course of EP at farm level and in the efficacy of M. hyopneumoniae vaccination suggest that the transmission and virulence characteristics of different field isolates of M. hyopneumoniae may vary. This paper reviews the current state of knowledge of the epidemiology of M. hyopneumoniae infection including its transmission, infection and seroconversion dynamics and also compares the various epidemiological tools used to monitor EP.
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Affiliation(s)
- Marina Sibila
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
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Maes D, Segales J, Meyns T, Sibila M, Pieters M, Haesebrouck F. Control of Mycoplasma hyopneumoniae infections in pigs. Vet Microbiol 2008; 126:297-309. [PMID: 17964089 PMCID: PMC7130725 DOI: 10.1016/j.vetmic.2007.09.008] [Citation(s) in RCA: 264] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Revised: 08/24/2007] [Accepted: 09/17/2007] [Indexed: 11/18/2022]
Abstract
Mycoplasma hyopneumoniae, the primary pathogen of enzootic pneumonia, occurs worldwide and causes major economic losses to the pig industry. The organism adheres to and damages the ciliated epithelium of the respiratory tract. Affected pigs show chronic coughing, are more susceptible to other respiratory infections and have a reduced performance. Control of the disease can be accomplished in a number of ways. First, management practices and housing conditions in the herd should be optimized. These include all-in/all-out production, limiting factors that may destabilize herd immunity, maintaining optimal stocking densities, prevention of other respiratory diseases, and optimal housing and climatic conditions. Strategic medication with antimicrobials active against M. hyopneumoniae and, preferably, also against major secondary bacteria may be useful during periods when the pigs are at risk for respiratory disease. Finally, commercial bacterins are widely used to control M. hyopneumoniae infections. The main effects of vaccination include less clinical symptoms, lung lesions and medication use, and improved performance. However, bacterins provide only partial protection and do not prevent colonization of the organism. Different vaccination strategies (timing of vaccination, vaccination of sows, vaccination combined with antimicrobial medication) can be used, depending on the type of herd, the production system and management practices, the infection pattern and the preferences of the pig producer. Research on new vaccines is actively occurring, including aerosol and feed-based vaccines as well as subunit and DNA vaccines. Eradication of the infection at herd level based on age-segregation and medication is possible, but there is a permanent risk for re-infections.
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Affiliation(s)
- D Maes
- Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
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