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Koutsoumanis K, Allende A, Alvarez Ordoñez A, Bolton D, Bover‐Cid S, Chemaly M, Herman L, Hilbert F, Lindqvist R, Nauta M, Nonno R, Peixe L, Skandamis P, Suffredini E, Fernandez Escamez P, Gonzales‐Barron U, Roberts H, Ru G, Simmons M, Cruz RB, Lourenço Martins J, Messens W, Ortiz‐Pelaez A, Simon AC, De Cesare A. Assessment on the efficacy of methods 2 to 5 and method 7 set out in Commission Regulation (EU) No 142/2011 to inactivate relevant pathogens when producing processed animal protein of porcine origin intended to feed poultry and aquaculture animals. EFSA J 2023; 21:e08093. [PMID: 37416785 PMCID: PMC10320699 DOI: 10.2903/j.efsa.2023.8093] [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] [Indexed: 07/08/2023] Open
Abstract
An assessment was conducted on the level of inactivation of relevant pathogens that could be present in processed animal protein of porcine origin intended to feed poultry and aquaculture animals when methods 2 to 5 and method 7, as detailed in Regulation (EU) No 142/2011, are applied. Five approved scenarios were selected for method 7. Salmonella Senftenberg, Enterococcus faecalis, spores of Clostridium perfringens and parvoviruses were shortlisted as target indicators. Inactivation parameters for these indicators were extracted from extensive literature search and a recent EFSA scientific opinion. An adapted Bigelow model was fitted to retrieved data to estimate the probability that methods 2 to 5, in coincidental and consecutive modes, and the five scenarios of method 7 are able to achieve a 5 log10 and a 3 log10 reduction of bacterial indicators and parvoviruses, respectively. Spores of C. perfringens were the indicator with the lowest probability of achieving the target reduction by methods 2 to 5, in coincidental and consecutive mode, and by the five considered scenarios of method 7. An expert knowledge elicitation was conducted to estimate the certainty of achieving a 5 log10 reduction of spores of C. perfringens considering the results of the model and additional evidence. A 5 log10 reduction of C. perfringens spores was judged: 99-100% certain for methods 2 and 3 in coincidental mode; 98-100% certain for method 7 scenario 3; 80-99% certain for method 5 in coincidental mode; 66-100% certain for method 4 in coincidental mode and for method 7 scenarios 4 and 5; 25-75% certain for method 7 scenario 2; and 0-5% certain for method 7 scenario 1. Higher certainty is expected for methods 2 to 5 in consecutive mode compared to coincidental mode.
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2
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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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Clinical Efficacy of Two Novel, Differentially Administered (IM, ID) Vaccines against Mycoplasma hyopneumoniae and PCV2 in Swine under Field Conditions. Animals (Basel) 2022; 12:ani12243467. [PMID: 36552387 PMCID: PMC9774315 DOI: 10.3390/ani12243467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 11/30/2022] [Accepted: 12/07/2022] [Indexed: 12/13/2022] Open
Abstract
Enzootic pneumonia (EP) of pigs is caused by Mycoplasma hyopneumoniae (M.hp.), which is, together with the porcine circovirus type 2 (PCV2), among the most prominent inducers of the porcine respiratory disease complex (PRDC). Therefore, vaccination of piglets against M.hp. and PCV2 is crucial in the fight against pulmonary infections. In this field study, we tested the clinical efficacy of two novel vaccines, one delivered IM (Hyogen® + Circovac®) and the other ID (MHyo-Sphere®PCV ID), on a fattening farm in Lower Austria with a history of still ongoing EP. Average daily weight gain, coughing/sneezing index, losses due to morbidity/mortality, and lung scoring data at slaughter by means of CLP (Ceva Lung Program) were recorded for three consecutive fattening cohorts to achieve a powerful number of animals, one half each vaccinated with the IM vaccine and the other half with the ID vaccine (n = 659 in total). No statistically significant differences could be observed between the two vaccination groups for the parameters investigated, but the total median EP score, which categorizes pulmonary lesions due to infection by M.hp. with a theoretical range of 0-28, was lowered from initially 1.9 to 1.0, indicating that both vaccines proved very suitable measures in the fight against EP.
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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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Tonni M, Formenti N, Boniotti MB, Guarneri F, Scali F, Romeo C, Pasquali P, Pieters M, Maes D, Alborali GL. The role of co-infections in M. hyopneumoniae outbreaks among heavy fattening pigs: a field study. Vet Res 2022; 53:41. [PMID: 35692039 PMCID: PMC9190078 DOI: 10.1186/s13567-022-01061-w] [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: 12/23/2021] [Accepted: 03/20/2022] [Indexed: 11/10/2022] Open
Abstract
Little is known about how co-infections and genotype dynamics affect Mycoplasma hyopneumoniae infection in fattening pigs. This study was aimed at assessing the role of co-infections in M. hyopneumoniae outbreaks, their influence on the presence of M. hyopneumoniae genotypes and their impact on consequent lung lesions. Tracheobronchial swabs (TBS) from 300 finishers were collected from 10 farms at the onset of enzootic pneumonia outbreaks and 1 month later, sampling of 3 groups per farm: Group A showed clinical signs first, Group B was housed near Group A, and Group C was located in a different building. Pigs’ lungs were scored at the slaughterhouse. TBS were tested for the main pathogens involved in respiratory diseases, and samples positive for M. hyopneumoniae were genotyped by multiple-locus variable-number tandem repeat analysis (MLVA). Pigs in Group A showed the highest prevalence and load of M. hyopneumoniae. A positive association was detected between M. hyopneumoniae and Mycoplasma hyorhinis, whereas Actinobacillus pleuropneumoniae was more frequent when the M. hyopneumoniae load was higher. Nevertheless, co-infection had no effect on lung lesion scores. The presence of multiple MLVA types (mixed infections) increased in time only in pigs from Group C and was positively associated with porcine reproductive and respiratory syndrome virus infection. Lung lesions were more severe in pigs with at least one TBS positive for M. hyopneumoniae and in pigs with a history of mixed infections. The central role of M. hyopneumoniae and relevance of mixed infections suggest that increased biosecurity might be beneficial for lung lesion sequelae.
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Affiliation(s)
- Matteo Tonni
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi, 9, 25124, Brescia, Italy.
| | - Nicoletta Formenti
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi, 9, 25124, Brescia, Italy
| | - M Beatrice Boniotti
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi, 9, 25124, Brescia, Italy
| | - Flavia Guarneri
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi, 9, 25124, Brescia, Italy
| | - Federico Scali
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi, 9, 25124, Brescia, Italy
| | - Claudia Romeo
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi, 9, 25124, Brescia, Italy
| | - Paolo Pasquali
- Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità viale Regina Elena 299, 00161, Rome, Italy
| | - Maria Pieters
- Department of Veterinary Population Medicine, University of Minnesota, 1365 Gortner Ave, St. Paul, MN, 55108, USA
| | - Dominiek Maes
- Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Giovanni L Alborali
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi, 9, 25124, Brescia, Italy
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Arenales A, Santana C, Rolim A, Pereira E, Nascimento E, Paixão T, Santos R. Histopathologic patterns and etiologic diagnosis of porcine respiratory disease complex in Brazil. ARQ BRAS MED VET ZOO 2022. [DOI: 10.1590/1678-4162-12439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
ABSTRACT Porcine respiratory disease complex is a major health concern for the porcine industry, causing significant economic loss. In this study, a total of 156 samples from pigs referred to a diagnostic laboratory in Brazil for 15 months were analyzed by histopathology, bacterial isolation, PCR, and immunohistochemistry. Multiple infections were common, so 42.3% of the pigs had more than one pathogen detected in the lungs. Swine influenza virus was detected in 25.0% of the cases. Porcine circovirus type 2 was detected in 7.1% of the pigs, which was often associated with Pasteurella multocida. In addition, one case of porcine circovirus type 3 infection associated with granulomatous pneumonia was diagnosed. Bacteria were isolated in 125 cases, namely Pasteurella multocida (34.0%), Glaesserella (Haemophilus) parasuis (35.2%), Streptococcus suis (13.5%), and Actinobacillus pleuropneumoniae (7.7%). Mycoplasma hyopneumoniae was identified in 7.0% of the cases, and 18.6% of pigs carried Salmonella sp. The most common patterns of pulmonary inflammation were broncopneumonia, bronchointerstitial pneumonia, and pleuritis, in that order. This study demonstrated that histopathology is an efficient tool along with other laboratorial diagnostic tests for establishing an etiologic diagnosis in cases of porcine respiratory disease complex.
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Affiliation(s)
- A. Arenales
- Universidade Federal de Minas Gerais, Brazil
| | | | - A.C.R. Rolim
- Instituto de Pesquisas Veterinárias Especializadas, Brasil
| | | | | | - T.A. Paixão
- Universidade Federal de Minas Gerais, Brazil
| | - R.L. Santos
- Universidade Federal de Minas Gerais, Brazil
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Balestrin E, Wolf JM, Wolf LM, Fonseca ASK, Ikuta N, Siqueira FM, Lunge VR. Molecular detection of respiratory coinfections in pig herds with enzootic pneumonia: a survey in Brazil. J Vet Diagn Invest 2022; 34:310-313. [PMID: 35034523 PMCID: PMC8921818 DOI: 10.1177/10406387211069552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Mycoplasma hyopneumoniae is the primary etiologic agent of swine enzootic pneumonia (EP), in which the immune response is reduced, making pigs susceptible to secondary infections. We surveyed commercial pig herds in Brazil for viral and bacterial respiratory coinfections that could complicate EP. Over a 2-y period (2015-2016), we found that 854 of 2,206 pigs (38.7%) were positive for M. hyopneumoniae in herds from various production systems in 3 Brazilian regions (Central-West, Southeast, South). We collected samples of 321 lungs positive for M. hyopneumoniae from 169 farms to also screen for Pasteurella multocida, Actinobacillus pleuropneumoniae, Glaesserella parasuis, influenza A virus (IAV), and porcine circovirus 2 (PCV2) by real-time PCR. The prevalence of pathogens found in addition to M. hyopneumoniae varied: P. multocida (141; 43.9%), G. parasuis (71; 22.1%), PCV2 (50; 15.6%), IAV (23; 7.2%), and A. pleuropneumoniae (18; 5.6%). G. parasuis was more frequent in farrowing or nursery herds (48.7%) than in breeding and fattening herds (10% and 18.6%, respectively; p < 0.01); A. pleuropneumoniae was found only in herds on farrow-to-finish and fattening farms.
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Affiliation(s)
- Eder Balestrin
- Laboratory of Molecular Diagnostic, Universidade Luterana do Brasil (ULBRA), Canoas, Rio Grande do Sul, Brazil
| | - Jonas M. Wolf
- Laboratory of Molecular Diagnostic, Universidade Luterana do Brasil (ULBRA), Canoas, Rio Grande do Sul, Brazil
| | - Lucas M. Wolf
- Laboratory of Molecular Diagnostic, Universidade Luterana do Brasil (ULBRA), Canoas, Rio Grande do Sul, Brazil
| | | | - Nilo Ikuta
- Simbios Biotecnologia, Cachoeirinha, Rio Grande do Sul, Brazil
| | - Franciele M. Siqueira
- Laboratory of Veterinary Bacteriology, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Rio Grande do Sul, Brazil
| | - Vagner R. Lunge
- Vagner R. Lunge, Laboratório de Diagnóstico Molecular, Universidade Luterana do Brasil (ULBRA), Canoas, RS, 92425-900, Brazil.
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Martelli P, Saleri R, Andrani M, Cavalli V, De Angelis E, Ferrari L, Borghetti P. Immune B cell responsiveness to single-dose intradermal vaccination against Mycoplasma hyopneumoniae. Res Vet Sci 2021; 141:66-75. [PMID: 34688042 DOI: 10.1016/j.rvsc.2021.10.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 09/21/2021] [Accepted: 10/05/2021] [Indexed: 10/20/2022]
Abstract
Mycoplasma hyopneumoniae is a major pathogen affecting pig herds and vaccination is the most utilized approach, despite providing partial protection. Age at vaccination, the delivery route, and vaccination protocol can influence vaccine efficacy. The influence of age and the presence of maternally-derived antibodies at vaccination on single-dose needle-less intradermal (ID) administration of an inactivated bacterin-based vaccine (Porcilis® M Hyo ID Once) were assessed in conventional pigs under field conditions. The induction of IgA+ and IgG+ B cell responses and the expression of the activation markers TLR2, TLR7, CCR9, and CCR10 were determined in PBMC. Vaccination at 4 weeks efficiently elicited an anamnestic antibody response associated with TLR2 and TLR7 upregulation. Although animals vaccinated at 1 week did not show seroconversion and a recall response upon infection, the responsiveness of Mycoplasma-recalled IgA+ B cells suggests the activation of mucosal immune cells after vaccination and infection. Vaccination at 1 week induced TLR2, TLR7, and CCR9 upregulation, suggesting the potential for systemic and local activation of immune cell trafficking between blood and target tissues. Vaccination at 4 weeks induced a CCR10 increase, suggesting that recalled IgA+ and IgG+ B cells can display an activated status upon infection. The antibody response after Mycoplasma infection in 4-week-old ID-vaccinated pigs was associated with TLR2 and CCR10 increases, confirming the potential use of this vaccination schedule for the safe and efficient delivery of single-dose M. hyopneumoniae vaccines. ID vaccination, especially at 4 weeks, was associated with a great degree of protection against enzootic pneumonia (EP)-like lung lesions.
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Affiliation(s)
- Paolo Martelli
- Department of Veterinary Science, University of Parma, Strada del Taglio, 10, Parma 43126, Italy.
| | - Roberta Saleri
- Department of Veterinary Science, University of Parma, Strada del Taglio, 10, Parma 43126, Italy.
| | - Melania Andrani
- Department of Veterinary Science, University of Parma, Strada del Taglio, 10, Parma 43126, Italy.
| | - Valeria Cavalli
- Department of Veterinary Science, University of Parma, Strada del Taglio, 10, Parma 43126, Italy.
| | - Elena De Angelis
- Department of Veterinary Science, University of Parma, Strada del Taglio, 10, Parma 43126, Italy.
| | - Luca Ferrari
- Department of Veterinary Science, University of Parma, Strada del Taglio, 10, Parma 43126, Italy.
| | - Paolo Borghetti
- Department of Veterinary Science, University of Parma, Strada del Taglio, 10, Parma 43126, Italy.
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Ferraz MES, Almeida HMS, Storino GY, Sonálio K, Souza MR, Moura CAA, Costa WMT, Lunardi L, Linhares DCL, de Oliveira LG. Lung consolidation caused by Mycoplasma hyopneumoniae has a negative effect on productive performance and economic revenue in finishing pigs. Prev Vet Med 2020; 182:105091. [PMID: 32683190 DOI: 10.1016/j.prevetmed.2020.105091] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 07/08/2020] [Accepted: 07/09/2020] [Indexed: 02/04/2023]
Abstract
This study aimed to measure the impact of productivity and the consequent economic losses related to lung lesions caused by M. hyopneumoniae. Five-hundred 75 days-old pigs were selected and weighed at the beginning and at the end of the finishing phase to assess the average daily gain (ADG). These animals were evaluated at the slaughter, and samples were collected for laboratory analysis to confirm the presence of M. hyopneumoniae DNA. The lungs of each pig were examined and classified into groups based on the extension of macroscopic lung lesions. Four-hundred eighty-six lungs were examined and 68.5% (n = 333) had macroscopic lung lesions. All pigs with lesions were positive for M. hyopneumoniae in qPCR. Linear mixed regression models (proc Glimmix) were performed on SAS to estimate the effect of macroscopic lung lesion scores on the ADG of finishing pigs. All pairwise comparisons among lesion score groups were performed using p < 0.05. For each increase of one percent in the lesion area, there was a decrease of 1.8 g in the daily weight gain. All the groups had a numerically lower ADG when compared to Group 1 (no lesions). The economic analysis was performed by simulation on Excel to estimate and compare the financial performance of the different lung lesion score groups. The negative correlation found between the group with no lung lesions and the group with more than 15.1% of lesions, showed a statistical difference in ADG, which could mean an opportunity to gain up to $ 6.55 per pig at slaughter. The presence of lesions causes the animals to decrease their productive potential, causing financial loss and generating impacts on the production system.
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Affiliation(s)
- M E S Ferraz
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - H M S Almeida
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - G Y Storino
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - K Sonálio
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - M R Souza
- Ceva Animal Health, Paulínia, São Paulo, Brazil
| | - C A A Moura
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - W M T Costa
- Ceva Animal Health, Paulínia, São Paulo, Brazil
| | - L Lunardi
- Ceva Animal Health, Paulínia, São Paulo, Brazil
| | - D C L Linhares
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - L G de Oliveira
- School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil.
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Almeida HMS, Mechler-Dreibi ML, Sonálio K, Ferraz MES, Storino GY, Barbosa FO, Maes D, Montassier HJ, de Oliveira LG. Cytokine expression and Mycoplasma hyopneumoniae burden in the development of lung lesions in experimentally inoculated pigs. Vet Microbiol 2020; 244:108647. [PMID: 32402328 DOI: 10.1016/j.vetmic.2020.108647] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 02/28/2020] [Accepted: 03/17/2020] [Indexed: 12/19/2022]
Abstract
This study aimed to assess immunopathological factors and M. hyopneumoniae (M. hyo) load in macroscopic lesion formation at four timepoints after experimental infection of swine. To do this, 24 M. hyo-free pigs were divided into two groups: non-inoculated control (n = 8) and inoculated (n = 16). At day 0 post-infection (dpi), animals of infected group were intratracheally inoculated with 5 mL of lung inoculum containing 107 CCU (Color Changing Units) ∕mL of M. hyo strain 232, while control group was mock infected with 5 mL of sterilized Friis medium. At 14, 28, 42 and 56 dpi, four animals from the infected group and two from the control group were euthanized and necropsied. The extent of macroscopic lung lobe lesions was visually assessed, scored and lesion samples (qPCR, histopathology and gene expression) were collected. The macroscopic lesion score and estimated M. hyo load (in copies/μL) at the different timepoints were: 14 dpi: 18.5 %-1.55 × 103 copies∕μL; 28dpi: 15.8 %-8.4 × 103 copies∕μL; 42 dpi: 7.0 %-3.2 × 104 copies∕μL and 56 dpi: 6.3 %-1.11 × 105 copies∕μL; Significant and positive correlations between macroscopic lung lesion and the pathogen load were found (coefficient range: 0.77-0.99). The cytokine's IL-6 (0.73) and INF-γ (-0.69) gene expression were significantly (p < 0.05) correlated to macroscopic lung lesion score while IL-8, TNF- α, IL-1α and IL-1β were associated to other pathological effects such as losses in average daily weight gain and microscopic lesion score. The results provide a better understanding about the pathogenicity of M. hyo strain 232 and the host-pathogen interactions, which may be helpful for the development of new treatments or control measures.
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Affiliation(s)
- Henrique M S Almeida
- São Paulo State University (Unesp), School of Agricultural and Veterinarian Sciences, Jaboticabal, SP, Brazil
| | - Marina L Mechler-Dreibi
- São Paulo State University (Unesp), School of Agricultural and Veterinarian Sciences, Jaboticabal, SP, Brazil
| | - Karina Sonálio
- São Paulo State University (Unesp), School of Agricultural and Veterinarian Sciences, Jaboticabal, SP, Brazil
| | - Maria Eugênia S Ferraz
- São Paulo State University (Unesp), School of Agricultural and Veterinarian Sciences, Jaboticabal, SP, Brazil
| | - Gabriel Y Storino
- São Paulo State University (Unesp), School of Agricultural and Veterinarian Sciences, Jaboticabal, SP, Brazil
| | - Fernanda O Barbosa
- São Paulo State University (Unesp), School of Agricultural and Veterinarian Sciences, Jaboticabal, SP, Brazil
| | - Dominiek Maes
- Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - Hélio J Montassier
- São Paulo State University (Unesp), School of Agricultural and Veterinarian Sciences, Jaboticabal, SP, Brazil
| | - Luis G de Oliveira
- São Paulo State University (Unesp), School of Agricultural and Veterinarian Sciences, Jaboticabal, SP, Brazil.
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11
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Antimicrobial susceptibility and genetic profile of Mycoplasma hyopneumoniae isolates from Brazil. Braz J Microbiol 2019; 51:377-384. [PMID: 31797326 DOI: 10.1007/s42770-019-00185-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 11/05/2019] [Indexed: 10/25/2022] Open
Abstract
Mycoplasma hyopneumoniae is the etiologic agent of porcine enzootic pneumonia, responsible for major production losses worldwide. The bacteria have a limited metabolism and need to obtain molecules from the growth environment, which causes multiple difficulties for in vitro culture. These limitations have a negative influence on the ability to carry out research for the development of the rational use of antimicrobials and vaccines. The objective of this investigation was to evaluate the genetic profile and in vitro susceptibility of field isolates of M. hyopneumoniae to different antimicrobials. All 16 isolates obtained from the samples presented 100% of identity in the partial sequence of 16S rRNA gene when compared to M. hyopneumoniae. A dendrogram was created using the PCR results of the genes related to pathogenicity, and the isolates were distributed into four clusters, suggesting genetic variability among four different isolates circulating on the same farm. The minimum inhibitory concentration of the isolates was higher for the antimicrobials tylosin (< 0.001-16 mg/L) and spiramycin (< 0.001-16 mg/L) than for enrofloxacin (< 0.001-0.125 mg/L) and tiamulin (< 0.001-0.125 mg/L). Our results demonstrate the genetic variability among M. hyopneumoniae isolates from pigs of the same farm, with differences in their susceptibility to antimicrobial agents.
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Fourour S, Marois-Créhan C, Martelet L, Fablet C, Kempf I, Gottschalk M, Segura M. Intra-Species and Inter-Species Differences in Cytokine Production by Porcine Antigen-Presenting Cells Stimulated by Mycoplasma hyopneumoniae, M. hyorhinis, and M. flocculare. Pathogens 2019; 8:pathogens8010034. [PMID: 30884861 PMCID: PMC6471550 DOI: 10.3390/pathogens8010034] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 03/08/2019] [Accepted: 03/09/2019] [Indexed: 02/03/2023] Open
Abstract
Mycoplasma hyorhinis and M. flocculare are commonly co-isolated with M. hyopneumoniae (primary agent of swine enzootic pneumonia) in gross pneumonia-like lesions, but their involvement in the disease process remains unknown. T cells play an immuno-pathological role during mycoplasmal infections. Dendritic cells (DCs) are major antigen-presenting cells involved in T cell activation and differentiation. In this study, we investigated cytokine (IL-6, IL-8, IL-10, IL-12, and TNF-α) production by porcine bone-marrow-derived DCs (BM-DCs) stimulated by M. hyopneumoniae, M. hyorhinis, and/or M. flocculare. Results showed that cytokine production levels were relatively homogenous for all evaluated M. hyopneumoniae strains in contrast to M. hyorhinis and M. flocculare strains. The most noteworthy inter-species differences were the overall (i) lower IL-12 production capacity of M. hyopneumoniae, and (ii) higher TNF-α production capacity of M. flocculare. Co-stimulation of BM-DCs showed that M. hyorhinis dominated the IL-12 production independently of its association with M. hyopneumoniae or M. flocculare. In addition, a decreased BM-DC production of TNF-α was generally observed in the presence of mycoplasma associations. Lastly, M. flocculare association with M. hyopneumoniae increased BM-DC ability to secrete IL-10. A higher cytotoxicity level in BM-DCs stimulated by M. hyorhinis was also observed. Overall, this study demonstrated that the combination of M. hyorhinis or M. flocculare with M. hyopneumoniae may participate to the modulation of the immune response that might affect the final disease outcome.
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Affiliation(s)
- Sarah Fourour
- French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Ploufragan-Plouzané-Niort Laboratory, Mycoplasmology Bacteriology and Antimicrobial Resistance Unit, 22 440 Ploufragan, France.
- University of Brittany-Loire, Cité internationale 1 place Paul Ricoeur CS 54417, 35044 Rennes, France.
| | - Corinne Marois-Créhan
- French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Ploufragan-Plouzané-Niort Laboratory, Mycoplasmology Bacteriology and Antimicrobial Resistance Unit, 22 440 Ploufragan, France.
- University of Brittany-Loire, Cité internationale 1 place Paul Ricoeur CS 54417, 35044 Rennes, France.
| | - Léa Martelet
- Swine and Poultry Infectious Diseases Research Center and Research Group on Infectious Diseases in Production Animals, Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte St., Saint-Hyacinthe, QC J2S 2M2, Canada.
| | - Christelle Fablet
- University of Brittany-Loire, Cité internationale 1 place Paul Ricoeur CS 54417, 35044 Rennes, France.
- French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Ploufragan-Plouzané-Niort Laboratory, Epidemiology, Health and Welfare unit, 22440 Ploufragan, France.
| | - Isabelle Kempf
- French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Ploufragan-Plouzané-Niort Laboratory, Mycoplasmology Bacteriology and Antimicrobial Resistance Unit, 22 440 Ploufragan, France.
- University of Brittany-Loire, Cité internationale 1 place Paul Ricoeur CS 54417, 35044 Rennes, France.
| | - Marcelo Gottschalk
- Swine and Poultry Infectious Diseases Research Center and Research Group on Infectious Diseases in Production Animals, Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte St., Saint-Hyacinthe, QC J2S 2M2, Canada.
| | - Mariela Segura
- Swine and Poultry Infectious Diseases Research Center and Research Group on Infectious Diseases in Production Animals, Faculty of Veterinary Medicine, University of Montreal, 3200 Sicotte St., Saint-Hyacinthe, QC J2S 2M2, Canada.
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Cvjetković V, Sipos S, Szabó I, Sipos W. Clinical efficacy of two vaccination strategies against Mycoplasma hyopneumoniae in a pig herd suffering from respiratory disease. Porcine Health Manag 2018; 4:19. [PMID: 30083374 PMCID: PMC6069710 DOI: 10.1186/s40813-018-0092-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 06/18/2018] [Indexed: 12/14/2022] Open
Abstract
Background A randomised field trial was conducted on an Austrian farrow-to-finish farm for one year to compare the efficacy of two commercial Mycoplasma hyopneumoniae vaccines. 585 piglets either received the one-shot formulation in group 1 (Hyogen®, 23.9 days of age) or a two-shot vaccine (Stellamune® Mycoplasma, 4.3 and 24.0 days of age) in group 2. Assessment of vaccine efficacy was evaluated by regression analyses through cough monitoring from nursery to slaughter, average daily weight gain from inclusion to slaughter, antibiotic treatment rate (ATR), mortality rate, and lung lesion scoring at slaughter. Results In general, coughing was more frequent during late nursery and finishing. No significant differences were found in the coughing index (0.02 vs 0.03) and mean average daily weight gain (560 vs 550 g) between the two groups. ATR was higher in group 2 (3.8 vs 9.6%). At the slaughterhouse check, significant differences in the prevalence of bronchopneumonia (62.9 vs 71.2%) could be found. Extension of lung lesions was also significantly lower in group 1 in terms of enzootic pneumonia (EP) values (p = 0.000, z = − 4.269). There were no significant differences in the rate of scarred lungs (20.0 vs 24.0%) or those affected by dorsocaudal pleurisy (36.8 vs 34.3%). Conclusions This trial demonstrated that Hyogen® was superior to Stellamune® Mycoplasma in reducing (I) the prevalence of bronchopneumonic lungs and those affected by cranioventral pleurisy, (II) the extension and severity of EP-like lung lesions, and (III) the rate of antibiotically treated animals against respiratory disease.
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Affiliation(s)
| | - Sabine Sipos
- Veterinary Practice Schwertfegen, Schwertfegen 2, 3040, Neulengbach, Austria
| | - Imre Szabó
- Ceva-Phylaxia, Co., Szállás u.5, Budapest, 1107 Hungary
| | - Wolfgang Sipos
- 4Clinic for Swine, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210 Vienna, Austria
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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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Polyamine-binding protein PotD2 is required for stress tolerance and virulence in Actinobacillus pleuropneumoniae. Antonie van Leeuwenhoek 2017; 110:1647-1657. [DOI: 10.1007/s10482-017-0914-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 07/15/2017] [Indexed: 10/19/2022]
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Zhang F, Cao S, Zhu Z, Yang Y, Wen X, Chang YF, Huang X, Wu R, Wen Y, Yan Q, Huang Y, Ma X, Zhao Q. Immunoprotective Efficacy of Six In vivo-Induced Antigens against Actinobacillus pleuropneumoniae as Potential Vaccine Candidates in Murine Model. Front Microbiol 2016; 7:1623. [PMID: 27818646 PMCID: PMC5073529 DOI: 10.3389/fmicb.2016.01623] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 09/29/2016] [Indexed: 11/21/2022] Open
Abstract
Six in vivo-induced (IVI) antigens—RnhB, GalU, GalT, Apl_1061, Apl_1166, and HflX were selected for a vaccine trial in a mouse model. The results showed that the IgG levels in each immune group was significantly higher than that of the negative control (P < 0.001). Except rRnhB group, proliferation of splenocytes was observed in all immunized groups and a relatively higher proliferation activity was observed in rGalU and rGalT groups (P < 0.05). In the rGalT vaccinated group, the proportion of CD4+ T cells in spleen was significant higher than that of negative control (P < 0.05). Moreover, proportions of CD4+ T cells in other vaccinated groups were all up-regulated to varying degrees. Up-regulation of both Th1 (IFN-γ, IL-2) and Th2 (IL-4) cytokines were detected. A survival rate of 87.5, 62.5, and 62.5% were obtained among rGalT, rAPL_1166, and rHflX group, respectively while the remaining three groups was only 25%. Histopathological analyses of lungs indicated that surviving animals from the vaccinated groups showed relatively normal pulmonary structure alveoli. These findings confirm that IVI antigens used as vaccine candidates provide partial protection against Actinobacillus pleuropneumoniae infection in a mouse model, which could be used as potential vaccine candidates in piglets.
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Affiliation(s)
- Fei Zhang
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Sanjie Cao
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China; Sichuan Science-observation Experiment of Veterinary Drugs and Veterinary Biological Technology, Ministry of AgricultureChengdu, China
| | - Zhuang Zhu
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Yusheng Yang
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Xintian Wen
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Yung-Fu Chang
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca NY, USA
| | - Xiaobo Huang
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Rui Wu
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Yiping Wen
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Qigui Yan
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China; Sichuan Science-observation Experiment of Veterinary Drugs and Veterinary Biological Technology, Ministry of AgricultureChengdu, China
| | - Yong Huang
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Xiaoping Ma
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Qin Zhao
- Research Center of Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
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Tzika ED, Tassis PD, Koulialis D, Papatsiros VG, Nell T, Brellou G, Tsakmakidis I. Field efficacy study of a novel ready-to-use vaccine against mycoplasma hyopneumoniae and porcine circovirus type 2 in a Greek farm. Porcine Health Manag 2015; 1:15. [PMID: 28405421 PMCID: PMC5382375 DOI: 10.1186/s40813-015-0006-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 09/15/2015] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND The primary objective of this study was to assess the efficacy, under field conditions, of a novel ready-to use Mycoplasma hyopneumoniae (M hyo) and Porcine circovirus type 2 (PCV2) combination vaccine given to piglets as one vaccination (1-shot) at 3 weeks of age. The study was carried out according to a controlled, randomised, and blinded design in a Greek pig herd with clinical M. hyo and subclinical PCV2 infection. Moreover, based on serology at the time of vaccination, the average PCV2 titre was 9.15 log2 and represented the level of maternally derived antibodies (MDA). In total 602 healthy suckling piglets, originating from 4 weekly farrowing batches were allocated randomly, within litters, to one of two groups. The pigs in one group were vaccinated with the test product and the other pigs were injected with saline. RESULTS Vaccination significantly reduced lesions of craneo-ventral pulmonary consolidation in vaccinated group [expressed as lung lesion score (LLS)] (Mixed model ANOVA: p < 0.0001). The mean LLS was 17.1 in the controls and 10.6 in the treatment group, respectively. The average daily weight gain (ADWG) during the finishing (54 g better in the treatment group) and whole study period (34 g better in vaccinated animals) was significantly greater in vaccinated than control pigs. The vaccinated pigs had a significant reduction of PCV2 viraemia when compared with the controls. CONCLUSIONS The test product was considered effective in the face of average MDA, based on significantly reduced severity of LLS and PCV2 viral load, as well as improved ADWG in vaccinated versus control pigs.
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Affiliation(s)
- Eleni D Tzika
- Farm Animals Clinic, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, University Campus, 54124 Thessaloniki, Greece
| | - Panagiotis D Tassis
- Farm Animals Clinic, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, University Campus, 54124 Thessaloniki, Greece
| | | | - Vassileios G Papatsiros
- Clinic of Medicine, Faculty of Veterinary Medicine, University of Thessaly, Trikalon 224, P.O. Box 199, Karditsa, Greece
| | - Tom Nell
- MSD Animal Health, Clinical Study Team Biologicals, P.O. Box 31, 5830 AA Boxmeer, The Netherlands
| | - Georgia Brellou
- Laboratory of Pathology, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, University Campus, 54124 Thessaloniki, Greece
| | - Ioannis Tsakmakidis
- Farm Animals Clinic, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, University Campus, 54124 Thessaloniki, Greece
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Ramirez C, Harding A, Forteguerri E, Aldridge B, Lowe J. Limited efficacy of antimicrobial metaphylaxis in finishing pigs: A randomized clinical trial. Prev Vet Med 2015; 121:176-8. [DOI: 10.1016/j.prevetmed.2015.06.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 06/03/2015] [Accepted: 06/04/2015] [Indexed: 11/15/2022]
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Abstract
The introduction into a naïve herd of animals sub-clinically infected with Actinobacillus pleuropneumoniae (App) is frequently the cause of clinical pleuropneumonia and the identification of such infected herds is a priority in the control of disease. Different serological tests for App have been developed and a number of these are routinely used. Some are species-specific whereas others identify more specifically the serotype/serogroup involved which requires updated information about important serotypes recovered from diseased pigs in a given area/country. Serotyping methods based on molecular techniques have been developed lately and are ready to be used by most diagnostic laboratories. When non-conclusive serological results are obtained, direct detection of App from tonsils is sometimes attempted. This review addresses different techniques and approaches used to monitor herds sub-clinically infected by this important pathogen.
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Affiliation(s)
- Marcelo Gottschalk
- Department of Pathology and Microbiology, Swine and Poultry Infectious Disease Center (CRIPA), Groupe de Recherche sur les Maladies Infectieuses du Porc (GREMIP), Faculty of Veterinary Medicine, University of Montreal, St-Hyacinthe, Québec, Canada J2S 2M2.
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