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Silva APSP, Almeida M, Michael A, Rahe MC, Siepker C, Magstadt DR, Piñeyro P, Arruda BL, Macedo NR, Sahin O, Gauger PC, Krueger KM, Mugabi R, Streauslin JS, Trevisan G, Linhares DCL, Silva GS, Fano E, Main RG, Schwartz KJ, Burrough ER, Derscheid RJ, Sitthicharoenchai P, Clavijo MJ. Detection and disease diagnosis trends (2017-2022) for Streptococcus suis, Glaesserella parasuis, Mycoplasma hyorhinis, Actinobacillus suis and Mycoplasma hyosynoviae at Iowa State University Veterinary Diagnostic Laboratory. BMC Vet Res 2023; 19:268. [PMID: 38087358 PMCID: PMC10714645 DOI: 10.1186/s12917-023-03807-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 11/07/2023] [Indexed: 12/18/2023] Open
Abstract
BACKGROUND Accurate measurement of disease associated with endemic bacterial agents in pig populations is challenging due to their commensal ecology, the lack of disease-specific antemortem diagnostic tests, and the polymicrobial nature of swine diagnostic cases. The main objective of this retrospective study was to estimate temporal patterns of agent detection and disease diagnosis for five endemic bacteria that can cause systemic disease in porcine tissue specimens submitted to the Iowa State University Veterinary Diagnostic Laboratory (ISU VDL) from 2017 to 2022. The study also explored the diagnostic value of specific tissue specimens for disease diagnosis, estimated the frequency of polymicrobial diagnosis, and evaluated the association between phase of pig production and disease diagnosis. RESULTS S. suis and G. parasuis bronchopneumonia increased on average 6 and 4.3%, while S. suis endocarditis increased by 23% per year, respectively. M. hyorhinis and A. suis associated serositis increased yearly by 4.2 and 12.8%, respectively. A significant upward trend in M. hyorhinis arthritis cases was also observed. In contrast, M. hyosynoviae arthritis cases decreased by 33% average/year. Investigation into the diagnostic value of tissues showed that lungs were the most frequently submitted sample, However, the use of lung for systemic disease diagnosis requires caution due to the commensal nature of these agents in the respiratory system, compared to systemic sites that diagnosticians typically target. This study also explored associations between phase of production and specific diseases caused by each agent, showcasing the role of S. suis arthritis in suckling pigs, meningitis in early nursery and endocarditis in growing pigs, and the role of G. parasuis, A. suis, M. hyorhinis and M. hyosynoviae disease mainly in post-weaning phases. Finally, this study highlighted the high frequency of co-detection and -disease diagnosis with other infectious etiologies, such as PRRSV and IAV, demonstrating that to minimize the health impact of these endemic bacterial agents it is imperative to establish effective viral control programs. CONCLUSIONS Results from this retrospective study demonstrated significant increases in disease diagnosis for S. suis, G. parasuis, M. hyorhinis, and A. suis, and a significant decrease in detection and disease diagnosis of M. hyosynoviae. High frequencies of interactions between these endemic agents and with viral pathogens was also demonstrated. Consequently, improved control programs are needed to mitigate the adverse effect of these endemic bacterial agents on swine health and wellbeing. This includes improving diagnostic procedures, developing more effective vaccine products, fine-tuning antimicrobial approaches, and managing viral co-infections.
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Affiliation(s)
- Ana Paula Serafini Poeta Silva
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Marcelo Almeida
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Alyona Michael
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Michael C Rahe
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Christopher Siepker
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Drew R Magstadt
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Pablo Piñeyro
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Bailey L Arruda
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
- United States Department of Agriculture (USDA), Ames, IA, USA
| | - Nubia R Macedo
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Orhan Sahin
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Philip C Gauger
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Karen M Krueger
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Robert Mugabi
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Jessica S Streauslin
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Giovani Trevisan
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Daniel C L Linhares
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Gustavo S Silva
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Eduardo Fano
- Boehringer Ingelheim Animal Health USA Inc, Atlanta, GA, USA
| | - Rodger G Main
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Kent J Schwartz
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Eric R Burrough
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Rachel J Derscheid
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Panchan Sitthicharoenchai
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Maria J Clavijo
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA.
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Zubair M, Wang J, Yu Y, Rasheed MA, Faisal M, Dawood AS, Ashraf M, Shao G, Feng Z, Xiong Q. Conserved Domains in Variable Surface Lipoproteins A-G of Mycoplasma hyorhinis May Serve as Probable Multi-Epitope Candidate Vaccine: Computational Reverse Vaccinology Approach. Vet Sci 2023; 10:557. [PMID: 37756079 PMCID: PMC10535464 DOI: 10.3390/vetsci10090557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 08/09/2023] [Accepted: 08/30/2023] [Indexed: 09/28/2023] Open
Abstract
Mycoplasma hyorhinis (M. hyorhinis) is responsible for infections in the swine population. Such infections are usually cured by using antimicrobials and lead to develop resistance. Until now, there has been no effective vaccine to eradicate the disease. This study used conserved domains found in seven members of the variable lipoprotein (VlpA-G) family in order to design a multi-epitope candidate vaccine (MEV) against M. hyorhinis. The immunoinformatics approach was followed to predict epitopes, and a vaccine construct consisting of an adjuvant, two B cell epitopes, two HTL epitopes, and one CTL epitope was designed. The suitability of the vaccine construct was identified by its non-allergen, non-toxic, and antigenic nature. A molecular dynamic simulation was executed to assess the stability of the TLR2 docked structure. An immune simulation showed a high immune response toward the antigen. The protein sequence was reverse-translated, and codons were optimized to gain a high expression level in E. coli. The proposed vaccine construct may be a candidate for a multi-epitope vaccine. Experimental validation is required in future to test the safety and efficacy of the hypothetical candidate vaccine.
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Affiliation(s)
- Muhammad Zubair
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing 210000, China; (M.Z.); (J.W.); (Y.Y.); (G.S.); (Z.F.)
- GuoTai (Taizhou) Center of Technology Innovation for Veterinary Biologicals, Taizhou 225300, China
| | - Jia Wang
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing 210000, China; (M.Z.); (J.W.); (Y.Y.); (G.S.); (Z.F.)
- GuoTai (Taizhou) Center of Technology Innovation for Veterinary Biologicals, Taizhou 225300, China
| | - Yanfei Yu
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing 210000, China; (M.Z.); (J.W.); (Y.Y.); (G.S.); (Z.F.)
- GuoTai (Taizhou) Center of Technology Innovation for Veterinary Biologicals, Taizhou 225300, China
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
| | - Muhammad Asif Rasheed
- Department of Biosciences, COMSATS University Islamabad, Sahiwal Campus, Islamabad 45550, Pakistan;
| | - Muhammad Faisal
- Division of Hematology, Department of Medicine, The Ohio State University College of Medicine, The Ohio State University Comprehensive Cancer Center, Columbus, OH 43210, USA;
| | - Ali Sobhy Dawood
- The State Key Laboratory of Agricultural Microbiology, Department of Preventive Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China;
- Faculty of Veterinary Medicine, University of Sadat City, Sadat City 32897, Egypt
| | - Muhammad Ashraf
- Institute of Microbiology, University of Agriculture Faisalabad, Faisalabad 37000, Pakistan;
| | - Guoqing Shao
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing 210000, China; (M.Z.); (J.W.); (Y.Y.); (G.S.); (Z.F.)
- GuoTai (Taizhou) Center of Technology Innovation for Veterinary Biologicals, Taizhou 225300, China
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Zhixin Feng
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing 210000, China; (M.Z.); (J.W.); (Y.Y.); (G.S.); (Z.F.)
- GuoTai (Taizhou) Center of Technology Innovation for Veterinary Biologicals, Taizhou 225300, China
| | - Qiyan Xiong
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing 210000, China; (M.Z.); (J.W.); (Y.Y.); (G.S.); (Z.F.)
- GuoTai (Taizhou) Center of Technology Innovation for Veterinary Biologicals, Taizhou 225300, China
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
- School of Life Sciences, Jiangsu University, Zhenjiang 212013, China
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Földi D, Nagy ZE, Belecz N, Szeredi L, Földi J, Kollár A, Tenk M, Kreizinger Z, Gyuranecz M. Establishment of a Mycoplasma hyorhinis challenge model in 5-week-old piglets. Front Microbiol 2023; 14:1209119. [PMID: 37601388 PMCID: PMC10436309 DOI: 10.3389/fmicb.2023.1209119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 07/17/2023] [Indexed: 08/22/2023] Open
Abstract
Introduction Mycoplasma hyorhinis is an emerging swine pathogen with high prevalence worldwide. The main lesions caused are arthritis and polyserositis, and the clinical manifestation of the disease may result in significant economic losses due to decreased weight gain and enhanced medical costs. We aimed to compare two challenge routes to induce M. hyorhinis infection using the same clinical isolate. Methods Five-week-old, Choice hybrid pigs were inoculated on 2 consecutive days by intravenous route (Group IV-IV) or by intravenous and intraperitoneal routes (Group IV-IP). Mock-infected animals were used as control (control group). After the challenge, the clinical signs were recorded for 28 days, after which the animals were euthanized. Gross pathological and histopathological examinations, PCR detection, isolation, and genotyping of the re-isolated Mycoplasma sp. and culture of bacteria other than Mycoplasma sp. were carried out. The ELISA test was used to detect anti-M. hyorhinis immunoglobulins in the sera of all animals. Results Pericarditis and polyarthritis were observed in both challenge groups; however, the serositis was more severe in Group IV-IV. Statistically significant differences were detected between the challenged groups and the control group regarding the average daily weight gain, pathological scores, and ELISA titers. Additionally, histopathological scores in Group IV-IV differed significantly from the scores in the control group. All re-isolated strains were the same or a close genetic variant of the original challenge strain. Discussion Our results indicate that both challenge routes are suitable for modeling the disease. However, due to the evoked more severe pathological lesions and the application being similar to the hypothesized natural route of infection in Group IV-IV, the two-dose intravenous challenge is recommended by the authors to induce serositis and arthritis associated with M. hyorhinis infection.
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Affiliation(s)
- Dorottya Földi
- Veterinary Medical Research Institute, Budapest, Hungary
- National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, Budapest, Hungary
| | - Zsófia Eszter Nagy
- Veterinary Medical Research Institute, Budapest, Hungary
- National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, Budapest, Hungary
| | - Nikolett Belecz
- Veterinary Medical Research Institute, Budapest, Hungary
- National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, Budapest, Hungary
| | - Levente Szeredi
- National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, Budapest, Hungary
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, Budapest, Hungary
| | | | - Anna Kollár
- National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, Budapest, Hungary
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, Budapest, Hungary
| | - Miklós Tenk
- National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, Budapest, Hungary
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, Budapest, Hungary
| | - Zsuzsa Kreizinger
- Veterinary Medical Research Institute, Budapest, Hungary
- National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, Budapest, Hungary
- MolliScience Kft., Biatorbágy, Hungary
| | - Miklós Gyuranecz
- Veterinary Medical Research Institute, Budapest, Hungary
- National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, Budapest, Hungary
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, Budapest, Hungary
- MolliScience Kft., Biatorbágy, Hungary
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Yu C, Cao M, Wei Y, Liu J, Zhang H, Liu C, Feng L, Huang L. Evaluation of cross-immunity among major porcine circovirus type 2 genotypes by infection with PCV2b and PCV2d circulating strains. Vet Microbiol 2023; 283:109796. [PMID: 37285792 DOI: 10.1016/j.vetmic.2023.109796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 05/28/2023] [Accepted: 05/30/2023] [Indexed: 06/09/2023]
Abstract
There are three main genotypes of porcine circovirus type 2 (PCV2), namely PCV2a, PCV2b and PCV2d, of which PCV2b and PCV2d are currently the most common. There are antigenic differences between these different genotypes. To explore the effect of PCV2 antigen differences on the immune protection provided by vaccines, a cross-immune protection test was carried out in pigs. Three genotype strains, PCV2a-CL, PCV2b-MDJ and PCV2d-LNHC, were inactivated and emulsified to prepare inactivated vaccines to immunize pigs, who were then challenged with the circulating strains PCV2b-BY and PCV2d-LNHC. Immunoperoxidase monolayer assays (IPMAs) and micro-neutralization assays were used to detect antibodies against the three different genotypes of PCV2. The results showed that the three genotype vaccines induced pigs to produce antibodies against the same and different genotypes of PCV2, but the levels of IPMA and neutralizing antibodies against the same genotype were higher than those against different genotypes. Quantitative Polymerase Chain Reaction (qPCR), virus titration and immunohistochemistry were used to detect PCV2 genomic DNA, live virus and antigen, respectively, in inguinal lymph nodes of experimental pigs. Following challenge with the PCV2b-BY strain, the viral DNA load in the inguinal lymph nodes of pigs immunized with the three genotype vaccines was reduced by more than 99 % compared to the unimmunized group. Following challenge with the PCV2d-LNHC strain, the viral DNA loads in the inguinal lymph nodes of pigs immunized with PCV2a, PCV2b and PCV2d genotype vaccines were reduced by 93.8 %, 99.8 % and 98.3 %, respectively, compared to unimmunized controls. In addition, neither live PCV2 virus nor antigen were detected in the inguinal lymph nodes of pigs immunized with any of the genotype vaccines (0/18), but both were detected in the lymph nodes of experimental pigs in the unimmunized control group (6/6). These findings suggest that, although the antigenic differences of the three genotype strains induce significant differences in antibody levels, they seem to have little effect on cross-protection between different genotypes.
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Affiliation(s)
- Chong Yu
- Division of Swine Digestive System Infectious Diseases, State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - Mengxiang Cao
- Division of Swine Digestive System Infectious Diseases, State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - Yanwu Wei
- Division of Swine Digestive System Infectious Diseases, State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - Jianhang Liu
- Division of Swine Digestive System Infectious Diseases, State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - Hao Zhang
- Division of Swine Digestive System Infectious Diseases, State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - Changming Liu
- Division of Swine Digestive System Infectious Diseases, State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - Li Feng
- Division of Swine Digestive System Infectious Diseases, State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China.
| | - Liping Huang
- Division of Swine Digestive System Infectious Diseases, State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China.
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Wang J, Hua L, Gan Y, Yuan T, Li L, Yu Y, Xie Q, Olaniran AO, Chiliza TE, Shao G, Feng Z, Pillay B, Xiong Q. Virulence and Inoculation Route Influence the Consequences of Mycoplasma hyorhinis Infection in Bama Miniature Pigs. Microbiol Spectr 2022;:e0249321. [PMID: 35446115 DOI: 10.1128/spectrum.02493-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mycoplasma hyorhinis is a widespread pathogen in pig farms worldwide. Although the majority of M. hyorhinis-colonized pigs have no apparent clinical disease, the pathogen can induce diseases such as polyserositis, arthritis, and eustachitis in some cases. To explore the mechanisms for the occurrence of these diseases, we challenged 4 groups of Bama miniature pigs with M. hyorhinis isolated from pigs without clinical symptoms (non-clinical origin [NCO] strain) or with typical clinical symptoms (clinical origin [CO] strain) and investigated the impacts of different strains and inoculation routes (intranasal [IN], intravenous [IV] + intraperitoneal [IP], and IV+IP+IN) on disease induction. Another group of pigs was set as a negative control. Pigs inoculated with the CO strain through a combined intravenous and intraperitoneal (IV+IP) route showed a significant decrease in average daily weight gain (ADWG), serious joint swelling, and lameness compared with the pigs in the negative-control group. Furthermore, this group developed moderate-to-severe pericarditis, pleuritis, peritonitis, and arthritis, as well as high levels of IgG and IgM antibodies. Pigs inoculated IV+IP with the NCO strain developed less marked clinical, pathological changes and a weaker specific antibody response compared with the pigs inoculated with the CO strain. The challenging results of the NCO strain via different routes (IV+IP, IV+IP+IN, and IN) indicated that the combined route (IV+IP) induced the most serious disease compared to the other inoculation routes. Intranasal inoculation induced a smaller decrease in ADWG without obvious polyserositis or arthritis. These data suggest that differences in both strain virulence and inoculation route affect the consequences of M. hyorhinis infection. IMPORTANCE Mycoplasma hyorhinis is a widespread pathogen in pig farms worldwide. The mechanisms or conditions that lead to the occurrence of disease in M. hyorhinis-infected pigs are still unknown. The objective of this study was to evaluate the impact of differences in the virulence of strain and the inoculation route on the consequences of M. hyorhinis infection.
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