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1.
BMC Vet Res ; 15(1): 342, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619295

RESUMO

BACKGROUND: The objective of this study was to assess the efficacy of a trivalent vaccine mixture and compare it to the respective monovalent vaccines against Mycoplasma hyopneumoniae, porcine circovirus type 2 (PCV2), and porcine reproductive and respiratory syndrome virus (PRRSV). RESULTS: Pigs that were triple challenged with M. hyopneumoniae, PCV2, and PRRSV following vaccination with the trivalent vaccine mixture exhibited a significantly better growth performance when compared to unvaccinated and challenged pigs. A statistical difference was not found when comparing pig populations which were vaccinated with the trivalent vaccine followed by a triple challenge and pigs vaccinated with monovalent M hyopneumoniae vaccine followed by mycoplasmal single challenge in the following areas: M. hyopneumoniae nasal shedding, the number of M. hyopneumoniae-specific interferon-γ secreting cells (IFN-γ-SC), and mycoplasmal lung lesion scores. Pigs vaccinated with the trivalent vaccine mixture followed by a triple challenge resulted in a similar reduction of PCV2 viremia, an increase in the number of PCV2-specific IFN-γ-SC and reduction in interstitial lung lesion scores when compared to pigs vaccinated with a PCV-2 vaccine and challenged with PCV2 only. Lastly, there was a significant difference in the reduction of PRRSV viremia, an increase in PRRSV-specific IFN-γ-SC and a reduction of interstitial lung lesion scores between pigs vaccinated with the trivalent vaccine mixture followed by a triple challenge and pigs vaccinated with a monovalent PRRSV vaccine followed by PRRSV challenge only. CONCLUSION: The trivalent vaccine mixture was efficacious against a triple challenge of M. hyopneumoniae, PCV2, and PRRSV. The trivalent vaccine mixture, however, did not result in equal protection when compared against each respective monovalent vaccine, with the largest vaccine occurring within PRRSV.


Assuntos
Circovirus/imunologia , Mycoplasma hyopneumoniae/imunologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Doenças dos Suínos/prevenção & controle , Vacinação/veterinária , Animais , Vacinas Bacterianas/imunologia , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/prevenção & controle , Feminino , Masculino , Pneumonia Suína Micoplasmática/imunologia , Pneumonia Suína Micoplasmática/prevenção & controle , Síndrome Respiratória e Reprodutiva Suína/imunologia , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Sus scrofa , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/microbiologia , Doenças dos Suínos/virologia , Vacinas Combinadas/administração & dosagem , Vacinas Combinadas/imunologia , Vacinas Virais/imunologia
2.
Prev Vet Med ; 168: 95-102, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31097130

RESUMO

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.


Assuntos
Mycoplasma hyopneumoniae , Pneumonia Suína Micoplasmática/economia , Doenças dos Suínos/economia , Agricultura/economia , Ração Animal , Animais , Antibacterianos/economia , Antibacterianos/uso terapêutico , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/economia , Análise Custo-Benefício , Feminino , Modelos Econômicos , Pneumonia Suína Micoplasmática/prevenção & controle , Suínos , Doenças dos Suínos/prevenção & controle , Fatores de Tempo
3.
Vet Rec ; 184(7): 222, 2019 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-30630875

RESUMO

This study investigated Mycoplasma hyopneumoniae colonisation and lung lesions at slaughter in pigs from vaccinated (V) and non-vaccinated (NV) sows, in two herds (A and B). In each herd, two sow batches were V against M. hyopneumoniae with a commercial bacterin at six and three weeks before farrowing and two sow batches remained NV. From each sow batch, laryngeal swabs were collected from the litters of five primiparous sows at weaning and seven days post-weaning. All samples were tested for M. hyopneumoniae by nested PCR. In total, 488 piglets were sampled. At slaughter, the extent of Mycoplasma-like pneumonia lesions (lung lesion score (LLS)) was assessed. The colonisation rates with M. hyopneumoniae at weaning and seven days post-weaning were (V-A=14.2, NV-A=20.0 (P=0.225); V-B=0.9, NV-B=0.8 (P=0.948)) and (V-A=0.8, NV-A=7.0 (P=0.039); V-B=1.8, NV-B=2.5 (P=0.738)), respectively. The average LLS (in per cent) was V-A=15.5, NV-A=26.4 (P=0.021); V-B=9.7, NV-B=8.4 (P=0.541). In conclusion, in herd A, with a substantially higher level of piglet colonisation at weaning than herd B, offspring from V sows had a significantly lower colonisation rate seven days post-weaning and a significantly lower LLS at slaughter compared with the offspring of the NV sows. This implies that sow vaccination might be useful for control of M. hyopneumoniae infections, although significant results may not be achieved at all times (such as in herd B).


Assuntos
Mycoplasma hyopneumoniae/isolamento & purificação , Pneumonia Suína Micoplasmática/prevenção & controle , Vacinação/veterinária , Animais , Contagem de Colônia Microbiana/veterinária , Feminino , Pulmão/microbiologia , Pulmão/patologia , Gravidez , Suínos
4.
Vet Microbiol ; 229: 7-13, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30642600

RESUMO

This study evaluated different gilt vaccination protocols against Mycoplasma (M.) hyopneumoniae at acclimation and their effect on the genetic diversity. A total of 180 M. hyopneumoniae naïve gilts were selected 1 week post-entry (wpe) at the acclimation barn in a clinically affected M. hyopneumoniae farm. Gilts were distributed according to the M. hyopneumoniae antibodies levels into three different vaccination schedules: A) four doses of a M. hyopneumoniae commercial vaccine at 2, 4, 6 and 8 wpe; B) two vaccine doses at 2 and 6 wpe and PBS at 4 and 8 wpe; and C) four PBS doses at the same wpe. Detection of M. hyopneumoniae (rt-PCR) and antibodies (ELISA) were assessed in gilts at 1, 14, 27 and 34 wpe and in 6 of their piglets at weaning. Rt-PCR positive gilts were detected at 14 wpe, being the proportion significantly lower in groups A and B (3/120, 3%) than C (27/60, 45%). Seroconversion was detected at 14 wpe, showing significant differences in percentage of inhibition (PI) between groups A (median 4.9, range 3.1-19.9) and B (5.5, 3.7-13.5), and C (14.3, 3.3-53.2). Gilts remained seropositive over the study and significant differences in PI were detected between groups A and B versus C. All piglets were rt-PCR negative, but the proportion of seropositive piglets coming from vaccinated gilts was significantly higher than the non-vaccinated group. M. hyopneumoniae characterization showed high variability. Hence, gilt vaccination with 2 or 4 doses significantly decreased the pathogen infectious pressure, variability, and provided high antibody levels to gilts and their offspring.


Assuntos
Aclimatação , Criação de Animais Domésticos , Vacinas Bacterianas/imunologia , Mycoplasma hyopneumoniae/imunologia , Pneumonia Suína Micoplasmática/prevenção & controle , Animais , Anticorpos Antibacterianos , Vacinas Bacterianas/administração & dosagem , Feminino , Esquemas de Imunização , Suínos
5.
Res Vet Sci ; 123: 144-152, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30665029

RESUMO

Mycoplasma hyopneumoniae (Mhp) is the pathogen of Mycoplasmal pneumonia of swine (MPS), a chronic respiratory infectious discease which causes enormous losses to the swine industry worldwide. At present, vaccination is the most effective mean to prevent and reduce economic losses caused by this pathogen. Currently, MPS vaccines mainly include inactivated vaccines and attenuated live vaccines. However, these approved vaccines still have many drawbacks, and the infection of Mhp has not yet been fully elucidated. Adhesion factors of Mhp have been shown to play a direct role in the pathogen's adherence, and thus were given consideration to be included in the composition of the vaccine. This shows a good prospect due to the advantages and feasibility of genetically engineering a vaccine. In this review, we summarize the work of researchers in recent years about the development of vaccines against Mhp, and we focus on the development of genetically engineering vaccines and some novel combined vaccines.


Assuntos
Vacinas Bacterianas/imunologia , Mycoplasma hyopneumoniae/imunologia , Pneumonia Suína Micoplasmática/prevenção & controle , Animais , Pneumonia Suína Micoplasmática/microbiologia , Suínos , Vacinação/métodos , Vacinas Atenuadas
6.
Artigo em Alemão | MEDLINE | ID: mdl-30340241

RESUMO

OBJECTIVE: The aim of this study was the scientific evaluation of an intradermal vaccination method in comparison to an intramuscular vaccination against Mycoplasma hyopneumoniae in suckling piglets with regard to skin reactions, performance parameters and procedural aspects. Possible effects on animal welfare should be deduced. MATERIAL AND METHODS: Under field conditions, 672 suckling piglets in three batches were vaccinated; 338 intradermally and 334 intramuscularly. In addition to a detailed scoring of the integument, the injection site with the local reaction was evaluated, scoring the swelling size (score 0-5), and rubor and incrustation (score 0-3). Moreover, piglets were weighed individually 1 day before vaccination and 8 days later. In addition, the time required for each vaccination was documented. RESULTS: On the first day after vaccination, 71.3 % of the intramuscularly vaccinated piglets and 2.7 % of the intradermally vaccinated piglets displayed no swelling at the vaccination site. No differences remained by the 7th day after vaccination. Daily weight gain did not differ significantly between the piglets in the intramuscularly (248 g) and intradermally (258 g) vaccinated groups. Intradermal vaccination took a mean of 11 seconds per piglet, while 17 seconds were required for intramuscular vaccination. CONCLUSIONS AND CLINICAL RELEVANCE: In this first study, no negative effects of the intradermal vaccination on performance parameters and no long-standing skin reactions were detected in the suckling piglets. Skin reactions were related to the desired immune reaction of the intradermal vaccination, but were no longer present after 7 days. Moreover, with regard to procedural aspects, the intradermal vaccination offered time saving advantages. To evaluate further possible effects on animal welfare, further analyses via video recordings are required.


Assuntos
Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/efeitos adversos , Erupção por Droga/veterinária , Mycoplasma hyopneumoniae/imunologia , Pneumonia Suína Micoplasmática/prevenção & controle , Doenças dos Suínos/etiologia , Bem-Estar do Animal , Animais , Animais Recém-Nascidos , Erupção por Droga/etiologia , Injeções Intradérmicas , Injeções Intramusculares , Pneumonia Suína Micoplasmática/imunologia , Sus scrofa , Suínos , Doenças dos Suínos/imunologia
7.
Vet Microbiol ; 223: 86-92, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30173757

RESUMO

In order to evaluate the sIgA-ELISA method reported previously for differentiating Mycoplasma hyopneumoniae (M. hyopneumoniae) infected from vaccinated pigs, dynamics of anti-M. hyopneumoniae secretory IgA (sIgA) antibody secretion in nasal mucus and IgG antibodies in serum from 10 pigs experimentally infected with M. hyopneumoniae or vaccinated with an inactivated vaccine were examined using sIgA-ELISA and a commercial M. hyopneumoniae antibody detection kit (IgG-ELISA), respectively. In addition, nasal swabs and serum samples from 2368 pigs of different ages originating from 10 pig farms with different M. hyopneumoniae infection and vaccination status were examined using the two ELISA. In the experimental model, anti-M. hyopneumoniae IgG antibodies were detected in both, the challenge group and the vaccine group. Anti-M. hyopneumoniae sIgA antibodies were detected in the challenge group from 7 days post challenge onwards, but not in the vaccine group. According to the data obtained from pig farms maintaining administration of inactivated vaccine, the prevalence of anti-M. hyopneumoniae sIgA antibody positive pigs was significantly lower than that of IgG antibody positive pigs. In non-vaccinating herds, the prevalence of sIgA antibodies was correlated with the severity of clinical symptoms typical for porcine enzootic pneumonia. In all suckling pigs, no matter vaccinated or not, the prevalence of anti-M. hyopneumoniae sIgA antibody positives was significantly lower than that of IgG antibody positives. These results prove that the sIgA-ELISA is a valuable method enabling the surveillance of M. hyopneumoniae infections in pig herds without interference due to maternally derived antibodies or antibodies induced by administration of inactivated vaccines.


Assuntos
Ensaio de Imunoadsorção Enzimática/veterinária , Imunoglobulina A Secretora/sangue , Mycoplasma hyopneumoniae/classificação , Pneumonia Suína Micoplasmática/prevenção & controle , Doenças dos Suínos/prevenção & controle , Animais , Feminino , Masculino , Mycoplasma hyopneumoniae/imunologia , Mycoplasma hyopneumoniae/isolamento & purificação , Pneumonia Suína Micoplasmática/diagnóstico , Pneumonia Suína Micoplasmática/microbiologia , Suínos , Doenças dos Suínos/microbiologia , Vacinação/veterinária , Vacinas de Produtos Inativados/imunologia
8.
J Vet Diagn Invest ; 30(5): 755-759, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29938600

RESUMO

Mycoplasma hyorhinis is an important pathogen of swine that can often occur as a respiratory coinfection with viral pathogens, but can also cause arthritis and polyserositis in infected animals. To date, no assay is available to assess the serologic response to M. hyorhinis vaccines, to our knowledge. We used recombinantly expressed M. hyorhinis p37 protein to monitor the magnitude of the IgG response in vaccinated animals. The assay was able to distinguish animals vaccinated with M. hyorhinis from those vaccinated with the other important Mycoplasma species: M. hyopneumoniae and M. hyosynoviae. When formulated with an ideal adjuvant, inactivated vaccines designed to protect animals against M. hyorhinis induced a measurable and dose-dependent antibody response against the p37 protein. Additionally, the protein appears to be highly conserved between strains of M. hyorhinis isolated in the United States. The specificity of the assay as well as the conservation and immunogenicity of the p37 protein make it an ideal candidate antigen for use in measuring the immune response against M. hyorhinis after vaccination in weaned pigs.


Assuntos
Vacinas Bacterianas/uso terapêutico , Mycoplasma hyorhinis/imunologia , Pneumonia Suína Micoplasmática/prevenção & controle , Vacinas de Produtos Inativados/uso terapêutico , Animais , Anticorpos Anti-Idiotípicos/sangue , Formação de Anticorpos , Vacinas Bacterianas/administração & dosagem , Ensaio de Imunoadsorção Enzimática/veterinária , Mycoplasma hyorhinis/patogenicidade , Sensibilidade e Especificidade , Suínos , Vacinação/veterinária , Vacinas de Produtos Inativados/administração & dosagem
9.
Vet Microbiol ; 219: 23-29, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29778201

RESUMO

Mycoplasma hyopneumoniae (M. hyopneumoniae) is the primary causative agent of enzootic pneumonia (EP), one of the most economically important infectious disease for the swine industry worldwide. M. hyopneumoniae transmission occurs mainly by direct contact (nose-to-nose) between infected to susceptible pigs as well as from infected dams to their offspring (sow-to-piglet). Since disease severity has been correlated with M. hyopneumoniae prevalence at weaning in some studies, and gilts are considered the main bacterial shedders, an effective gilt acclimation program should help controlling M. hyopneumoniae in swine farms. The present review summarizes the different M. hyopneumoniae monitoring strategies of incoming gilts and recipient herd and proposes a farm classification according to their health statuses. The medication and vaccination programs against M. hyopneumoniae most used in replacement gilts are reviewed as well. Gilt replacement acclimation against M. hyopneumoniae in Europe and North America indicates that vaccination is the main strategy used, but there is a current trend in US to deliberately expose gilts to the pathogen.


Assuntos
Aclimatação , Mycoplasma hyopneumoniae/isolamento & purificação , Pneumonia Suína Micoplasmática/prevenção & controle , Vacinação/veterinária , Animais , Europa (Continente)/epidemiologia , Fazendas , América do Norte/epidemiologia , Pneumonia Suína Micoplasmática/epidemiologia , Pneumonia Suína Micoplasmática/microbiologia , Pneumonia Suína Micoplasmática/transmissão , Prevalência , Suínos , Vacinação/métodos
10.
Can J Vet Res ; 82(1): 39-47, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29382967

RESUMO

The objective of this study was to compare clinical, microbiologic, immunologic, and pathologic parameters in pigs each concurrently administered porcine reproductive and respiratory syndrome virus (PRRSV), Mycoplasma hyopneumoniae, and porcine circovirus type 2 (PCV2) vaccine from 1 of 2 commercial sources at 21 days of age and challenged with field strains of each of the 3 pathogens. Pigs were challenged with PRRSV and M. hyopneumoniae at 42 days of age (-14 days post-challenge, dpc) followed by a challenge with PCV2 at 56 days of age (0 dpc). Significant differences were observed between vaccinated challenged and unvaccinated challenged groups in clinical (average daily gain and clinical signs), microbiologic (viremia and nasal shedding), immunologic (antibodies and interferon-γ secreting cells), and pathologic (lesions) outcomes. Significant differences were observed among the 3 vaccinated challenged groups in microbiologic (nasal shedding of M. hyopneumoniae and viremia of PCV2) and immunologic (M. hyopneumoniae- and PCV2-specific interferon-γ secreting cells) outcomes. The vaccination regimen for PRRSV vaccine, M. hyopneumoniae vaccine, and PCV2 vaccine is efficacious for controlling triple challenge with PRRSV, M. hyopneumoniae, and PCV2 from weaning to finishing period.


Assuntos
Infecções por Circoviridae/veterinária , Circovirus , Pneumonia Suína Micoplasmática/prevenção & controle , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vacinação/veterinária , Animais , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/imunologia , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/prevenção & controle , Circovirus/classificação , Circovirus/imunologia , DNA Viral/sangue , Mycoplasma hyopneumoniae/imunologia , Pneumonia Suína Micoplasmática/microbiologia , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , RNA Viral/sangue , Suínos , Doenças dos Suínos/microbiologia , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/virologia , Fatores de Tempo , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia , Viremia/veterinária
11.
Transbound Emerg Dis ; 65 Suppl 1: 110-124, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28834294

RESUMO

Mycoplasma hyopneumoniae (M. hyopneumoniae) is the primary pathogen of enzootic pneumonia, a chronic respiratory disease in pigs. Infections occur worldwide and cause major economic losses to the pig industry. The present paper reviews the current knowledge on M. hyopneumoniae infections, with emphasis on identification and analysis of knowledge gaps for optimizing control of the disease. Close contact between infected and susceptible pigs is the main route of M. hyopneumoniae transmission. Management and housing conditions predisposing for infection or disease are known, but further research is needed to better understand M. hyopneumoniae transmission patterns in modern pig production systems, and to assess the importance of the breeding population for downstream disease control. The organism is primarily found on the mucosal surface of the trachea, bronchi and bronchioles. Different adhesins and lipoproteins are involved in the adherence process. However, a clear picture of the virulence and pathogenicity of M. hyopneumoniae is still missing. The role of glycerol metabolism, myoinositol metabolism and the Mycoplasma Ig binding protein-Mycoplasma Ig protease system should be further investigated for their contribution to virulence. The destruction of the mucociliary apparatus, together with modulating the immune response, enhances the susceptibility of infected pigs to secondary pathogens. Clinical signs and severity of lesions depend on different factors, such as management, environmental conditions and likely also M. hyopneumoniae strain. The potential impact of strain variability on disease severity is not well defined. Diagnostics could be improved by developing tests that may detect virulent strains, by improving sampling in live animals and by designing ELISAs allowing discrimination between infected and vaccinated pigs. The currently available vaccines are often cost-efficient, but the ongoing research on developing new vaccines that confer protective immunity and reduce transmission should be continued, as well as optimization of protocols to eliminate M. hyopneumoniae from pig herds.


Assuntos
Controle de Doenças Transmissíveis/métodos , Doenças Transmissíveis/veterinária , Mycoplasma hyopneumoniae/patogenicidade , Pneumonia Suína Micoplasmática/prevenção & controle , Animais , Ensaio de Imunoadsorção Enzimática/veterinária , Pneumonia Suína Micoplasmática/diagnóstico , Pneumonia Suína Micoplasmática/transmissão , Suínos , Virulência
12.
Mem Inst Oswaldo Cruz ; 112(12): 812-816, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29211241

RESUMO

BACKGROUND: The B subunit of Escherichia coli heat-labile enterotoxin (LTB) is a potent mucosal immune adjuvant. However, there is little information about LTB's potential as a parenteral adjuvant. OBJECTIVES: We aimed at evaluating and better understanding rLTB's potential as a parenteral adjuvant using the fused R1 repeat of Mycoplasma hyopneumoniae P97 adhesin as an antigen to characterise the humoral immune response induced by this construct and comparing it to that generated when aluminium hydroxide is used as adjuvant instead. METHODS: BALB/c mice were immunised intraperitoneally with either rLTBR1 or recombinant R1 adsorbed onto aluminium hydroxide. The levels of systemic anti-rR1 antibodies (total Ig, IgG1, IgG2a, and IgA) were assessed by enzyme-linked immunosorbent assay (ELISA). The ratio of IgG1 and IgG2a was used to characterise a Th1, Th2, or mixed Th1/Th2 immune response. FINDINGS: Western blot confirmed rR1, either alone or fused to LTB, remained antigenic; anti-cholera toxin ELISA confirmed that LTB retained its activity when expressed in a heterologous system. Mice immunised with the rLTBR1 fusion protein produced approximately twice as much anti-rR1 immunoglobulins as mice vaccinated with rR1 adsorbed onto aluminium hydroxide. Animals vaccinated with either rLTBR1 or rR1 adsorbed onto aluminium hydroxide presented a mixed Th1/Th2 immune response. We speculate this might be a result of rR1 immune modulation rather than adjuvant modulation. Mice immunised with rLTBR1 produced approximately 1.5-fold more serum IgA than animals immunised with rR1 and aluminium hydroxide. MAIN CONCLUSIONS: The results suggest that rLTB is a more powerful parenteral adjuvant than aluminium hydroxide when administered intraperitoneally as it induced higher antibody titres. Therefore, we recommend that rLTB be considered an alternative adjuvant, even if different administration routes are employed.


Assuntos
Adesinas Bacterianas/imunologia , Adjuvantes Imunológicos/administração & dosagem , Toxinas Bacterianas/administração & dosagem , Enterotoxinas/administração & dosagem , Proteínas de Escherichia coli/administração & dosagem , Mycoplasma hyopneumoniae/imunologia , Pneumonia Suína Micoplasmática/prevenção & controle , Hidróxido de Alumínio , Animais , Toxinas Bacterianas/imunologia , Enterotoxinas/imunologia , Ensaio de Imunoadsorção Enzimática , Proteínas de Escherichia coli/imunologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Pneumonia Suína Micoplasmática/imunologia , Suínos
13.
Mem. Inst. Oswaldo Cruz ; 112(12): 812-816, Dec. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-894861

RESUMO

BACKGROUND The B subunit of Escherichia coli heat-labile enterotoxin (LTB) is a potent mucosal immune adjuvant. However, there is little information about LTB's potential as a parenteral adjuvant. OBJECTIVES We aimed at evaluating and better understanding rLTB's potential as a parenteral adjuvant using the fused R1 repeat of Mycoplasma hyopneumoniae P97 adhesin as an antigen to characterise the humoral immune response induced by this construct and comparing it to that generated when aluminium hydroxide is used as adjuvant instead. METHODS BALB/c mice were immunised intraperitoneally with either rLTBR1 or recombinant R1 adsorbed onto aluminium hydroxide. The levels of systemic anti-rR1 antibodies (total Ig, IgG1, IgG2a, and IgA) were assessed by enzyme-linked immunosorbent assay (ELISA). The ratio of IgG1 and IgG2a was used to characterise a Th1, Th2, or mixed Th1/Th2 immune response. FINDINGS Western blot confirmed rR1, either alone or fused to LTB, remained antigenic; anti-cholera toxin ELISA confirmed that LTB retained its activity when expressed in a heterologous system. Mice immunised with the rLTBR1 fusion protein produced approximately twice as much anti-rR1 immunoglobulins as mice vaccinated with rR1 adsorbed onto aluminium hydroxide. Animals vaccinated with either rLTBR1 or rR1 adsorbed onto aluminium hydroxide presented a mixed Th1/Th2 immune response. We speculate this might be a result of rR1 immune modulation rather than adjuvant modulation. Mice immunised with rLTBR1 produced approximately 1.5-fold more serum IgA than animals immunised with rR1 and aluminium hydroxide. MAIN CONCLUSIONS The results suggest that rLTB is a more powerful parenteral adjuvant than aluminium hydroxide when administered intraperitoneally as it induced higher antibody titres. Therefore, we recommend that rLTB be considered an alternative adjuvant, even if different administration routes are employed.


Assuntos
Animais , Feminino , Camundongos , Toxinas Bacterianas/toxicidade , Adjuvantes Imunológicos/administração & dosagem , Adesinas Bacterianas/imunologia , Proteínas de Escherichia coli/administração & dosagem , Proteínas de Escherichia coli/imunologia , Pneumonia Suína Micoplasmática/imunologia , Pneumonia Suína Micoplasmática/prevenção & controle , Enterotoxinas/administração & dosagem , Suínos , Ensaio de Imunoadsorção Enzimática , Mycoplasma hyopneumoniae , Hidróxido de Alumínio
14.
BMC Vet Res ; 13(1): 285, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28915878

RESUMO

BACKGROUND: Mycoplasma hyopneumoniae (Mhp) causes porcine enzootic pneumonia, a disease that cause major economic losses in the pig industry. Dendritic cells (DCs), the most effective antigen-presenting cells, are widely distributed beneath respiratory epithelium, DCs uptake and present antigens to T cells, to initiate protective immune responses in different infections. In this study, we investigated the role of porcine DCs in vaccine Mhp-168 exposure. RESULTS: The antigen presenting ability of DCs were improved by vaccine Mhp-168 exposure. DCs could activate T-cell proliferation by up-regulating the antigen presenting molecule MHCII expression and co-stimulatory molecule CD80/86. However, the up-regulation of IL-10 and accompany with down-regulation of IFN-γ gene level may account for the limitation of attenuated Mhp-168 strain use as vaccine alone. CONCLUSION: These findings are benefit for exploring the protection mechanisms and the possible limitations of this attenuated Mhp-168 vaccine.


Assuntos
Vacinas Bacterianas/imunologia , Células Dendríticas/imunologia , Mycoplasma hyopneumoniae/imunologia , Animais , Células Cultivadas , Macrófagos/fisiologia , Pneumonia Suína Micoplasmática/microbiologia , Pneumonia Suína Micoplasmática/prevenção & controle , Organismos Livres de Patógenos Específicos , Suínos
15.
Vet Rec ; 181(13): 348, 2017 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-28893974

RESUMO

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.


Assuntos
Injeções Intradérmicas/veterinária , Injeções Intramusculares/veterinária , Mycoplasma hyopneumoniae , Pneumonia Suína Micoplasmática/prevenção & controle , Vacinação/veterinária , Animais , Vacinas Bacterianas , Suínos , Vacinação/métodos
16.
BMC Vet Res ; 13(1): 274, 2017 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-28851359

RESUMO

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.


Assuntos
Vacinas Bacterianas/administração & dosagem , Mycoplasma hyopneumoniae , Pneumonia Suína Micoplasmática/prevenção & controle , Animais , Anticorpos Antibacterianos/análise , Líquido da Lavagem Broncoalveolar/imunologia , Citocinas/análise , DNA Bacteriano/análise , Relação Dose-Resposta Imunológica , Pulmão/patologia , Mycoplasma hyopneumoniae/imunologia , Mycoplasma hyopneumoniae/isolamento & purificação , Mycoplasma hyopneumoniae/patogenicidade , Pneumonia Suína Micoplasmática/imunologia , Pneumonia Suína Micoplasmática/patologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Especificidade da Espécie , Suínos
18.
Vet Rec ; 181(1): 19, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28601840

RESUMO

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.


Assuntos
Vacinas Bacterianas/administração & dosagem , Pneumonia Suína Micoplasmática/prevenção & controle , Vacinação/veterinária , Desmame , Animais , Esquemas de Imunização , Suínos , Resultado do Tratamento , Vacinação/métodos
19.
BMC Vet Res ; 13(1): 91, 2017 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-28388953

RESUMO

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.


Assuntos
Infecções por Circoviridae/veterinária , Imunidade Materno-Adquirida , Mycoplasma hyopneumoniae/imunologia , Pneumonia Suína Micoplasmática/prevenção & controle , Doenças dos Suínos/prevenção & controle , Vacinação/veterinária , Animais , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/prevenção & controle , Circovirus/imunologia , Feminino , Grécia , Pulmão/patologia , Masculino , Pneumonia Suína Micoplasmática/imunologia , Suínos , Doenças dos Suínos/imunologia , Vacinas Combinadas/imunologia , Viremia , Ganho de Peso
20.
Vet Microbiol ; 201: 146-153, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28284602

RESUMO

Enzootic Pneumonia (EP) is caused by the Mycoplasma hyopneumoniae pathogenic bacteria, and it represents a significant respiratory disease that is responsible for major economic losses within the pig industry throughout the world. The bacterins that are currently commercially available have been proven to offer only partial protection against M. hyopneumoniae, and the development of more efficient vaccines is required. Several recombinant antigens have been evaluated via different immunization strategies and have been found to be highly immunogenic. This work describes the construction and immunological characterization of a multi-antigen chimera composed of four M. hyopneumoniae antigens: P97R1, P46, P95, and P42. Immunogenic regions of each antigen were selected and combined to encode a single polypeptide. The gene was cloned and expressed in Escherichia coli, and the chimeric protein was recognized by specific antibodies against each subunit, as well as by convalescent pig sera. The immunogenic properties of the chimera were then evaluated in a mice model through two recombinant vaccines that were formulated as follows: (1) purified chimeric protein plus adjuvant or (2) recombinant Escherichia coli bacterin. The immune response induced in BALB/c mice immunized with each formulation was characterized in terms of total IgG levels, IgG1, and IgG2a isotypes against each antigen present in the chimera. The results of the study indicated that novel chimeric protein is a potential candidate for the future development of a more effective vaccine against EP.


Assuntos
Antígenos de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Imunoglobulina G/sangue , Mycoplasma hyopneumoniae/imunologia , Pneumonia Suína Micoplasmática/prevenção & controle , Adjuvantes Imunológicos , Animais , Antígenos de Bactérias/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Feminino , Imunização/veterinária , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Mycoplasma hyopneumoniae/genética , Pneumonia Suína Micoplasmática/microbiologia , Proteínas Recombinantes , Suínos , Vacinas Sintéticas/imunologia
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