Molecular prevalence of Mycoplasma parvum in production cycle of technified swine herds / Prevalência molecular do Mycoplasma parvum em granjas de suínos tecnificados de ciclo completo

Porcine hemoplasmosis is characterized as a geographically cosmopolitan disease caused by Mycoplasma suis and Mycoplasma parvum. Asymptomatic pigs are considered the focus of hemoplasmosis because they are carriers and reservoirs to new infections. This study aimed to determine the molecular occurrence of porcine hemoplasmas (PH) in the production cycle of technified farrow-to-finished swine herds. For this purpose, 20 swine herds were evaluated, where 501 whole blood samples were collected for qPCR and phylogenetic analyses for hemoplasmas. The epidemiological analysis was performed for the entire population and per the growth stage. The total prevalence for PH was 31.93% (161/501); 95% (19/20) of sampled herds were positive. The occurrence of PH by swine growth stages was nursery (30.47%), growing (31.29%), finishing (26.18%), and slaughter (40.25%). The quantification cycles (Cq) ranged from 3.18-39.56 and the number of PH 16S rRNA copies per µL of DNA ranged from 5,57 x10 to 2.23 x1010 . Sequencing and phylogenetic analysis of five selected samples showed 100% identity with M. parvum strain Indiana and two M. parvum sequences from Brazil/Goiás. This is the first report on PH in technified herds in Southeastern Brazil by growth stages.

A hemoplasmose suína é uma doença geograficamente cosmopolita, causada por Mycoplasma suis e Mycoplasma parvum. Suínos assintomáticos são considerados foco de hemoplasmose por serem portadores e reservatórios de novas infecções. Este estudo teve como objetivo determinar a ocorrência molecular de hemoplasmas suínos (HP) no ciclo de produção de rebanhos suínos tecnificados. Foram avaliados 20 rebanhos suínos e coletadas 501 amostras de sangue total para qPCR e análises filogenéticas para hemoplasmas. A análise epidemiológica foi realizada pela população e por estágio de crescimento. A prevalência total de HP foi de 31,93% (161/501); 95% (19/20) dos rebanhos amostrados foram positivos. A ocorrência de HP por fases de crescimento dos suínos foi: creche (30,47%), em crescimento (31,29%), acabamento (26,18%) e abate (40,25%). Os ciclos de quantificação (Cq) variaram de 3,18-39,56 e o número de cópias de rRNA PH 16S por µL de DNA variou de 5,57 x102 a 2,23 x10¹0. O sequenciamento e a análise filogenética de cinco amostras selecionadas mostraram 100% de identidade com a cepa indiana de M. parvum e duas sequências de M. parvum do Brasil / Goiás. Este é o primeiro relato de HP em rebanhos tecnificados, na região Sudeste do Brasil, por estágios de crescimento.

Molecular survey of hemotropic mycoplasmas in crab-eating raccoons (Procyon cancrivorus) in southern Brazil / Levantamento molecular de micoplasma hemotrópico em mão-pelada (Procyon cancrivorus) do sul do Brasil

Hemoplasmas are non-cultivable bacterial parasites of erythrocytes that infect domestic and wild animals, as well as humans. Their means of transmission and pathogenesis remain contentious issues and difficult to evaluate in wild animals. Procyon cancrivorus is a South American carnivore and occurs in all Brazilian biomes. In this study, we aimed to investigate occurrences of hemoplasmas infecting P. cancrivorus and to identify their 16S rRNA gene, in southern Brazil. DNA was extracted from spleen and blood samples of P. cancrivorus (n = 9) from different locations. Hemoplasma DNA was detected in six samples, based on 16S rRNA gene amplification and phylogenetic analysis. Four of the six sequences belonged to the "Mycoplasma haemofelis group", which is closely related to genotypes detected in Procyon lotor from the USA; one was within the "Mycoplasma suis group", closely related to "Candidatus Mycoplasma haemominutum"; and one was within the intermediate group between these clusters. Thus, these sequences showed that the molecular identity of hemoplasmas in the population studied was very variable. In five positive animals, Amblyomma aureolatum ticks and a flea (Ctenocephalides felis felis) were collected. The present study describes the first molecular detection of mycoplasmas in P. cancrivorus.(AU)

Os micoplasmas hemotrópicos (hemoplasmas) são parasitas bacterianos não-cultiváveis de eritrócitos que infectam tanto animais domésticos e selvagens, como seres humanos. A transmissão e a patogênese são discutíveis e difíceis de avaliar em animais selvagens. O mão pelada (Procyon cancrivorus) é um carnívoro Sul-americano, que ocorre em todos os biomas brasileiros. O objetivo do presente estudo é o de investigar a ocorrência de hemoplasmas infectando P. cancrivorus e identificar seu gene 16S rRNA no Sul do Brasil. O DNA foi extraído do baço e amostras de sangue de P. cancrivorus (n= 9). O DNA de hemoplasma foi detectado em seis amostras, com base na amplificação do gene 16S rRNA e na análise filogenética. Quatro das seis sequências pertencem ao "Grupo Mycoplasma haemofelis", que estão intimamente relacionadas aos genótipos detectados no Procyon lotor dos EUA; uma dentro do "Grupo Mycoplasma suis", que está intimamente relacionado ao "Candidatus Mycoplasma haemominutum", e uma dentro do grupo intermediário entre esses clusters, mostrando assim que há uma diversidade genética de hemoplasmas na população estudada. Em cinco animais positivos, foram coletados carrapatos Amblyomma aureolatum e uma pulga Ctenocephalides felis. O presente estudo traz a primeira detecção molecular de micoplasmas em P. cancrivorus.(AU)

Histopathologic patterns and etiologic diagnosis of porcine respiratory disease complex in Brazil / Padrões histopatológicos e diagnóstico etiológico do complexo de doenças respiratórias dos suínos no Brasil

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.

O complexo de doenças respiratórias de suínos é um dos principais problemas sanitários na suinocultura, causando perdas econômicas significativas. O presente estudo incluiu amostras de 156 suínos, que foram encaminhados a um laboratório de diagnóstico no Brasil, durante um período de 15 meses, sendo realizados histopatologia, isolamento bacteriano, PCR e imuno-histoquímica. Coinfecções por múltiplos patógenos foram comuns, correspondendo a 42,3% dos animais, que tiveram mais de um agente identificado nos pulmões. O vírus da influenza suína foi detectado em 25,0%. O circovírus suíno tipo 2 foi detectado em 7,1% dos animais, frequentemente associado à Pasteurella multocida. Além disso, foi diagnosticado um caso de circovírus suíno tipo 3 associado à pneumonia granulomatosa. Foram isoladas bactérias em 125 casos, a saber: Pasteurella multocida (34,0%), Glaesserella (Haemophilus) parasuis (35,2%), Streptococcus suis (13,5%) e Actinobacillus pleuropneumoniae (7,7%). Mycoplasma hyopneumoniae foi identificado em 7,0%, e 18,6% dos animais tiveram isolamento de Salmonella sp. Os padrões mais frequentes de inflamação pulmonar foram: broncopneumonia, pneumonia broncointersticial e pleurite, nesta ordem. Este estudo demonstrou que a histopatologia é uma ferramenta eficiente, juntamente a outras técnicas laboratoriais de diagnóstico, para o estabelecimento de diagnóstico etiológico em casos do complexo de doenças respiratórias de suínos.

Bacterial pneumonia in captive wild boars in southern Brazil: etiological and pathological causes

Respiratory diseases are one of the major health issues described in intensive pig production, causing important economic losses. However, there is little information on the prevalence, etiology and clinical-pathological presentation of these diseases in wild boars. For this reason, this work investigated the presence in captive wild boars of pneumonic lesions and bacterial pathogens commonly detected and associated with respiratory diseases in domestic pigs. A total of 226 captive wild boar lungs from two farms were examined in a slaughterhouse in Southern Brazil. The pneumonic lesions were classified as cranioventral, dorsocaudal, and disseminated, and the quantification of lesions was calculated. From the total of 226 lungs, 121 were collected for laboratory examination. Lungs with macroscopic lesions suggestive of pneumonia were collected for histological, bacteriological and molecular analysis. The molecular analysis was performed to detect the presence of Actinobacillus (A.) pleuropneumoniae, Glaesserella (G.) parasuis, Mycoplasma (M.) hyopneumoniae, Mycoplasma (M.) hyorhinis and Streptococcus (S.) suis serotype 2. The percentages of histological lesions and bacterial agents and their association were calculated. Cranioventral consolidation (75.2%) was the most prevalent macroscopic lung lesion, followed by disseminated (21.5%) and dorsocaudal (3.3%) distribution. Microscopically, chronic lesions were the most prevalent, representing 70.2% of the lungs. Moreover, BALT hyperplasia was present in 86.5% of the lungs, suppurative bronchopneumonia in 65.7%, and alveoli infiltrate in 46.8%. Six bacterial pathogens commonly described as agents of pig pneumonia were identified by bacterial or molecular methods: Pasteurella (P.) multocida, S. suis, M. hyopneumoniae, A. pleuropneumoniae, G. parasuis and M. hyorhinis. Twenty-eight different combinations of pathogens were identified in 84 samples (69.4%). The most common combinations were: M. hyopneumoniae and A. pleuropneumoniae (13.1%), M. hyopneumoniae, G. parasuis and M. hyorhinis (10.7%), and M. hyopneumoniae, A. pleuropneumoniae and G. parasuis (8.3%). Additionally, M. hyopneumoniae was the most frequent pathogen detected in this study, representing 58.7% of the samples. The detection of M. hyopneumoniae and M. hyorhinis by PCR was associated with the presence of BALT hyperplasia (P < 0.05) and there was also an association between the detection of M. hyopneumoniae by PCR and suppurative bronchopneumonia (P < 0.05). In addition, a significant association (P < 0.05) between the detection of M. hyopneumoniae and A. pleuropneumoniae by PCR and the histological classification (acute, subacute or chronic lesions) was observed. The results of this study were similar to those observed in slaughtered domestic pigs, although, the detection of opportunist pathogens was less frequent than that usually described in pig pneumonia. The high prevalence of pneumonia in captive wild boars at slaughter and the similar characteristics of pneumonia in captive wild boars and domestic pigs suggest that the close phylogenetic relationship between pigs and wild boars could influence the susceptibility of both species to the colonization of the same pathogens, indicating that captive wild boars raised in confined conditions could be predisposed to respiratory diseases, similar to domestic pigs.(AU)

Agents of pneumonia in slaughtered pigs in southern Brazil / Agentes patogênicos de pneumonia em suínos abatidos no sul do Brasil

A high prevalence of pneumonic lesions has been reported to affect slaughtered pigs in southern Brazil. In order to identify which microorganisms have been causing those lesions, 30 pig lungs presenting pneumonic gross lesions were collected from five different slaughterhouses, totaling 150 lungs. Samples for bacterial isolation, molecular, histopathologic and immunohistochemistry (IHC) evaluation were taken from each lung. The pneumonic lesion scoring ranged from 1.53 to 2.83. The most frequent histopathological lesions found was the concomitant Influenza A virus (IAV) and Mycoplasma hyopneumoniae infection, corresponding to 55.3% (83/150), and Pasteurella multocida type A was isolated in 54.2% (45/83) of these cases. In 102 samples (68%), there was histopathologic suggestion of involvement of more than one infectious agent. M. hyopneumoniae was the most frequent agent associated with pneumonic lesions, being present in 92.1% (94/102) of the lungs with coinfections, followed by IAV in 89.2% (91/102). Besides the coinfections, IAV lesions were observed also in six samples without another pathogenic microorganism detected. A total of 46 samples with acute and subacute IAV suspected lesions in histopathological examination were assessed for IHC and real time RT-PCR for IAV. A total of 35% (16/46) of them were positive by IHC and 13% (6/46) by real time RT-PCR. Regarding M. hyopneumoniae, 79.3% (119/150) of samples were positive by qPCR and 84.9% (101/119) of them also presented M. hyopneumoniae suspected lesions in the histopathological examination. The results of this study suggest the importance of IAV in respiratory diseases in finishing pigs, even though this virus is more frequently reported in the nursery phase. In addition, our results emphasize the importance of lung coinfections in finishing pigs.(AU)

Lesões sugestivas de pneumonia são frequentemente encontradas em altas prevalências em suínos abatidos no sul do Brasil. Para identificar quais microrganismos causam essas lesões, foram coletados 30 pulmões de suínos com lesão macroscópica sugestiva de pneumonia em cinco frigoríficos diferentes, totalizando 150 pulmões. Amostras para isolamento bacteriano, avaliação molecular, histopatológica e imuno-histoquímica (IHC) foram coletadas de cada pulmão. O escore de lesão pulmonar variou entre 1,53 a 2,83. O achado histopatológico mais observado foi a lesão sugestiva de infecção concomitante pelo vírus Influenza A (IAV) e Mycoplasma (M.) hyopneumoniae, correspondendo a 55,3% (83/150), e em 54,2% (45/83) desses casos Pasteurella (P.) multocida tipo A foi isolado. Em 102 amostras (68%), houve lesão histopatológica sugestiva do envolvimento de mais de um agente infeccioso. M. hyopneumoniae foi o microrganismo mais frequente associado a lesões de pneumonia, estando presente em 92,1% (94/102) dos pulmões com coinfecções, seguido de IAV, que foi encontrado em 89,2% (91/102). Além das coinfecções, lesões de IAV foram observadas em mais seis amostras que não aparentavam envolvimento de outro agente infeccioso. Um total de 46 amostras com suspeita de lesão aguda e subaguda de IAV no exame histopatológico foram avaliadas para IHC e RT-PCR em tempo real para IAV e 35% (16/46) delas foram positivas por IHC e 13% (6/46) foram positivas por RT-PCR em tempo real. Com relação a M. hyopneumoniae, 79,3% (119/150) das amostras foram positivas por qPCR e 84,9% (101/119) delas também apresentaram lesões suspeitas de M. hyopneumoniae no exame histopatológico. Os resultados deste trabalho sugerem a importância do IAV como agente causador de pneumonias em suínos de terminação, embora esse vírus seja mais frequentemente relatado na fase de creche. Além disso, os achados deste trabalho demonstram a presença frequente de coinfecções pulmonares em suínos de terminação.(AU)

Agents of pneumonia in slaughtered pigs in southern Brazil / Agentes patogênicos de pneumonia em suínos abatidos no sul do Brasil

A high prevalence of pneumonic lesions has been reported to affect slaughtered pigs in southern Brazil. In order to identify which microorganisms have been causing those lesions, 30 pig lungs presenting pneumonic gross lesions were collected from five different slaughterhouses, totaling 150 lungs. Samples for bacterial isolation, molecular, histopathologic and immunohistochemistry (IHC) evaluation were taken from each lung. The pneumonic lesion scoring ranged from 1.53 to 2.83. The most frequent histopathological lesions found was the concomitant Influenza A virus (IAV) and Mycoplasma hyopneumoniae infection, corresponding to 55.3% (83/150), and Pasteurella multocida type A was isolated in 54.2% (45/83) of these cases. In 102 samples (68%), there was histopathologic suggestion of involvement of more than one infectious agent. M. hyopneumoniae was the most frequent agent associated with pneumonic lesions, being present in 92.1% (94/102) of the lungs with coinfections, followed by IAV in 89.2% (91/102). Besides the coinfections, IAV lesions were observed also in six samples without another pathogenic microorganism detected. A total of 46 samples with acute and subacute IAV suspected lesions in histopathological examination were assessed for IHC and real time RT-PCR for IAV. A total of 35% (16/46) of them were positive by IHC and 13% (6/46) by real time RT-PCR. Regarding M. hyopneumoniae, 79.3% (119/150) of samples were positive by qPCR and 84.9% (101/119) of them also presented M. hyopneumoniae suspected lesions in the histopathological examination. The results of this study suggest the importance of IAV in respiratory diseases in finishing pigs, even though this virus is more frequently reported in the nursery phase. In addition, our results emphasize the importance of lung coinfections in finishing pigs.(AU)

Lesões sugestivas de pneumonia são frequentemente encontradas em altas prevalências em suínos abatidos no sul do Brasil. Para identificar quais microrganismos causam essas lesões, foram coletados 30 pulmões de suínos com lesão macroscópica sugestiva de pneumonia em cinco frigoríficos diferentes, totalizando 150 pulmões. Amostras para isolamento bacteriano, avaliação molecular, histopatológica e imuno-histoquímica (IHC) foram coletadas de cada pulmão. O escore de lesão pulmonar variou entre 1,53 a 2,83. O achado histopatológico mais observado foi a lesão sugestiva de infecção concomitante pelo vírus Influenza A (IAV) e Mycoplasma (M.) hyopneumoniae, correspondendo a 55,3% (83/150), e em 54,2% (45/83) desses casos Pasteurella (P.) multocida tipo A foi isolado. Em 102 amostras (68%), houve lesão histopatológica sugestiva do envolvimento de mais de um agente infeccioso. M. hyopneumoniae foi o microrganismo mais frequente associado a lesões de pneumonia, estando presente em 92,1% (94/102) dos pulmões com coinfecções, seguido de IAV, que foi encontrado em 89,2% (91/102). Além das coinfecções, lesões de IAV foram observadas em mais seis amostras que não aparentavam envolvimento de outro agente infeccioso. Um total de 46 amostras com suspeita de lesão aguda e subaguda de IAV no exame histopatológico foram avaliadas para IHC e RT-PCR em tempo real para IAV e 35% (16/46) delas foram positivas por IHC e 13% (6/46) foram positivas por RT-PCR em tempo real. Com relação a M. hyopneumoniae, 79,3% (119/150) das amostras foram positivas por qPCR e 84,9% (101/119) delas também apresentaram lesões suspeitas de M. hyopneumoniae no exame histopatológico. Os resultados deste trabalho sugerem a importância do IAV como agente causador de pneumonias em suínos de terminação, embora esse vírus seja mais frequentemente relatado na fase de creche. Além disso, os achados deste trabalho demonstram a presença frequente de coinfecções pulmonares em suínos de terminação.(AU)

Molecular detection of Mycoplasma suis in extensive pig production systems in the State of Maranhão, northeast Brazil / Detecção molecular de Mycoplasma suis em suínos de criações extensivas no estado do Maranhão, nordeste do Brasil

Mycoplasma suis is a bacterium that causes hemoplasmosis in pigs. This agent is capable of adhering to the surface of porcine erythrocytes, inducing structural changes on these cells. In Brazil, there are few reports about the disease, its causal agent, and the economic impact of this pathogen on pig production systems and farm sanitation. The present study aimed to investigate the occurrence of M. suis in extensive swine farms located in the counties of Itapecuru Mirim, Santa Rita and Rosario, State of Maranhão, northeast Brazil. For such purpose, 64 blood samples of pigs from these facilities were tested for M. suis using a 16S rRNA gene-based quantitative real-time PCR (qPCR); 82.3%, 65.2% and 25% of blood samples of swine from farms in the cities of Itapecuru Mirim, Santa Rita and Rosario were positive for M. suis by qPCR, respectively. This study shows, for the first time, that M. suis circulates in pig populations from the state of Maranhão, Northeast Brazil.(AU)

Mycoplasma suis é uma bactéria que causa a hemoplasmose em suínos. Este agente é capaz de se aderir à superfície dos eritrócitos de suínos, ocasionando deformações estruturais nestas células. No Brasil, poucos são os relatos acerca do parasita, da infecção e de seus impactos econômicos nas esferas produtiva e sanitária. O objetivo deste estudo foi investigar, por meio da PCR em tempo real quantitativa (qPCR) baseada no gene 16S rRNA, a ocorrência de M. suis em 64 amostras de sangue de suínos de criações extensivas dos municípios de Itapecuru Mirim, Santa Rita e Rosário, localizados no estado do Maranhão. Foram obtidos um percentual de 82,3%, 65,2% e 25% de amostras positivas na qPCR para M. suis nos municípios de Itapecuru Mirim, Santa Rita e Rosário, respectivamente. Este estudo mostra que M. suis circula entre os suínos de criações extensivas no estado do Maranhão.(AU)

Molecular detection of Mycoplasma suis in extensive pig production systems in the State of Maranhão, northeast Brazil / Detecção molecular de Mycoplasma suis em suínos de criações extensivas no estado do Maranhão, nordeste do Brasil

Mycoplasma suis is a bacterium that causes hemoplasmosis in pigs. This agent is capable of adhering to the surface of porcine erythrocytes, inducing structural changes on these cells. In Brazil, there are few reports about the disease, its causal agent, and the economic impact of this pathogen on pig production systems and farm sanitation. The present study aimed to investigate the occurrence of M. suis in extensive swine farms located in the counties of Itapecuru Mirim, Santa Rita and Rosario, State of Maranhão, northeast Brazil. For such purpose, 64 blood samples of pigs from these facilities were tested for M. suis using a 16S rRNA gene-based quantitative real-time PCR (qPCR); 82.3%, 65.2% and 25% of blood samples of swine from farms in the cities of Itapecuru Mirim, Santa Rita and Rosario were positive for M. suis by qPCR, respectively. This study shows, for the first time, that M. suis circulates in pig populations from the state of Maranhão, Northeast Brazil.

Mycoplasma suis é uma bactéria que causa a hemoplasmose em suínos. Este agente é capaz de se aderir à superfície dos eritrócitos de suínos, ocasionando deformações estruturais nestas células. No Brasil, poucos são os relatos acerca do parasita, da infecção e de seus impactos econômicos nas esferas produtiva e sanitária. O objetivo deste estudo foi investigar, por meio da PCR em tempo real quantitativa (qPCR) baseada no gene 16S rRNA, a ocorrência de M. suis em 64 amostras de sangue de suínos de criações extensivas dos municípios de Itapecuru Mirim, Santa Rita e Rosário, localizados no estado do Maranhão. Foram obtidos um percentual de 82,3%, 65,2% e 25% de amostras positivas na qPCR para M. suis nos municípios de Itapecuru Mirim, Santa Rita e Rosário, respectivamente. Este estudo mostra que M. suis circula entre os suínos de criações extensivas no estado do Maranhão.

Molecular detection of Mycoplasma suis in extensive pig production systems in the State of Maranhão, northeast Brazil / Detecção molecular de Mycoplasma suis em suínos de criações extensivas no estado do Maranhão, nordeste do Brasil

Mycoplasma suis is a bacterium that causes hemoplasmosis in pigs. This agent is capable of adhering to the surface of porcine erythrocytes, inducing structural changes on these cells. In Brazil, there are few reports about the disease, its causal agent, and the economic impact of this pathogen on pig production systems and farm sanitation. The present study aimed to investigate the occurrence of M. suis in extensive swine farms located in the counties of Itapecuru Mirim, Santa Rita and Rosario, State of Maranhão, northeast Brazil. For such purpose, 64 blood samples of pigs from these facilities were tested for M. suis using a 16S rRNA gene-based quantitative real-time PCR (qPCR); 82.3%, 65.2% and 25% of blood samples of swine from farms in the cities of Itapecuru Mirim, Santa Rita and Rosario were positive for M. suis by qPCR, respectively. This study shows, for the first time, that M. suis circulates in pig populations from the state of Maranhão, Northeast Brazil.(AU)

Mycoplasma suis é uma bactéria que causa a hemoplasmose em suínos. Este agente é capaz de se aderir à superfície dos eritrócitos de suínos, ocasionando deformações estruturais nestas células. No Brasil, poucos são os relatos acerca do parasita, da infecção e de seus impactos econômicos nas esferas produtiva e sanitária. O objetivo deste estudo foi investigar, por meio da PCR em tempo real quantitativa (qPCR) baseada no gene 16S rRNA, a ocorrência de M. suis em 64 amostras de sangue de suínos de criações extensivas dos municípios de Itapecuru Mirim, Santa Rita e Rosário, localizados no estado do Maranhão. Foram obtidos um percentual de 82,3%, 65,2% e 25% de amostras positivas na qPCR para M. suis nos municípios de Itapecuru Mirim, Santa Rita e Rosário, respectivamente. Este estudo mostra que M. suis circula entre os suínos de criações extensivas no estado do Maranhão.(AU)

Anatomopathological pneumonic aspects associated with highly pathogenic Pasteurella multocida in finishing pigs / Aspectos pneumônicos anatomo-patológicos associados a Pasteurella multocida de alta patogenicidade em suínos de terminação

The bacterium Pasteurella multocida is a frequent cause of porcine respiratory disease complex in finishing pigs. Historically, the bacterium is recognized as an opportunistic agent, causing secondary bacterial pneumonia in pigs. Several Brazilian reports have suggested the ability of P. multocida to cause primary pulmonary infection that leads to the death of finishing pigs prior to slaughter. The aim of this study was to evaluate anatomopathological pulmonary findings associated with P. multocida infection that were obtained from animals with clinical respiratory disease and from animals at slaughter. Twenty-five lung samples from 14 herds of finishing pigs with acute clinical respiratory disease and 19 lungs collected at slaughter from a different set of 14 herds were studied. In all lung samples, bacterial isolation was performed, and only samples with pure P. multocida growth were included in the study. Gross and histopathological lesions were evaluated, as well as Influenza A, porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae co-infections. Pleuritis and pericarditis were more often observed in clinical samples (P<0.05). Moreover, there was a numerical trend indicating that pericarditis, lymphadenomegaly and cavity exudates were more often present in clinical samples. Thirteen lung samples were negative to M. hyopneumoniae, Influenza A and PCV2 by immunohistochemistry (IHC), with only P. multocida identified. In these cases, gross lesions such as pleuritis, pericarditis and lymphadenomegaly were always present, and no histologic lesions indicative of other agents such as Actinobacillus pleuropneumoniae, Actinobacillus suis or Haemophilus parasuis were observed. These findings suggest the ability of some P. multocida isolates to cause primary respiratory and systemic infection. However, in this study, it was not possible to determine specific virulence markers to explain these findings.

A bactéria Pasteurella multocida é causa frequente do Complexo de Doenças Respiratórias dos suínos em animais de terminação. Historicamente, a bactéria é reconhecida como agente oportunista, causando pneumonia bacteriana secundária. Diversos relatos brasileiros sugerem a habilidade da P. multocida de causar infecção pulmonar primária que leva a mortalidade de animais de terminação antes do abate. O objetivo deste estudo foi avaliar achados anatomopatológicos pulmonares associados com infecção por P. multocida, obtidas de animais acometidos clinicamente por doença respiratória e de animais ao abate. Avaliou-se 25 amostras de pulmão de 14 rebanhos obtidas de animais de terminação com sinais clínicos de doença respiratória aguda, e 19 pulmões coletados ao abate de 14 rebanhos diferentes. Em todos os pulmões, realizou-se isolamento bacteriano, e apenas amostras com crescimento puro de P. multocida foram incluídas no trabalho. Avaliou-se as lesões macro e microscopicamente, assim como co-infecções por Influenza A, Circovirus suíno tipo 2 (PCV2) e Mycoplasma hyopneumoniae. Pleurite e pericardite foram mais frequentemente observadas em amostras clinicas (P<0,05). Ainda, houve tendência numérica indicando a ocorrência de linfadenomegalia e exsudação cavitária, mais presentes em amostras clínicas. Treze amostras de pulmão foram negativas para M. hyopneumoniae, Influenza A e PCV2 por imunoistoquímica (IHQ), com identificação de apenas P. multocida. Nestes casos, lesões macroscópicas como pleurite, pericardite e linfadenomegalia foram sempre presentes, sem lesões histológicas indicativas de outros agentes como Actinobacillus pleuropneumoniae, Actinobacillus suis ou Haemophilus parasuis. Estes achados sugerem a habilidade de alguns isolados de P. multocida de causarem quadro respiratório primário e infecção sistêmica. No entanto, neste estudo, não foi possível determinar marcadores de virulência específicos para justificar tais achados.

Anatomopathological pneumonic aspects associated with highly pathogenic Pasteurella multocida in finishing pigs / Aspectos pneumônicos anatomo-patológicos associados a Pasteurella multocida de alta patogenicidade em suínos de terminação

The bacterium Pasteurella multocida is a frequent cause of porcine respiratory disease complex in finishing pigs. Historically, the bacterium is recognized as an opportunistic agent, causing secondary bacterial pneumonia in pigs. Several Brazilian reports have suggested the ability of P. multocida to cause primary pulmonary infection that leads to the death of finishing pigs prior to slaughter. The aim of this study was to evaluate anatomopathological pulmonary findings associated with P. multocida infection that were obtained from animals with clinical respiratory disease and from animals at slaughter. Twenty-five lung samples from 14 herds of finishing pigs with acute clinical respiratory disease and 19 lungs collected at slaughter from a different set of 14 herds were studied. In all lung samples, bacterial isolation was performed, and only samples with pure P. multocida growth were included in the study. Gross and histopathological lesions were evaluated, as well as Influenza A, porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae co-infections. Pleuritis and pericarditis were more often observed in clinical samples (P<0.05). Moreover, there was a numerical trend indicating that pericarditis, lymphadenomegaly and cavity exudates were more often present in clinical samples. Thirteen lung samples were negative to M. hyopneumoniae, Influenza A and PCV2 by immunohistochemistry (IHC), with only P. multocida identified. In these cases, gross lesions such as pleuritis, pericarditis and lymphadenomegaly were always present, and no histologic lesions indicative of other agents such as Actinobacillus pleuropneumoniae, Actinobacillus suis or Haemophilus parasuis were observed. These findings suggest the ability of some P. multocida isolates to cause primary respiratory and systemic infection. However, in this study, it was not possible to determine specific virulence markers to explain these findings.(AU)

A bactéria Pasteurella multocida é causa frequente do Complexo de Doenças Respiratórias dos suínos em animais de terminação. Historicamente, a bactéria é reconhecida como agente oportunista, causando pneumonia bacteriana secundária. Diversos relatos brasileiros sugerem a habilidade da P. multocida de causar infecção pulmonar primária que leva a mortalidade de animais de terminação antes do abate. O objetivo deste estudo foi avaliar achados anatomopatológicos pulmonares associados com infecção por P. multocida, obtidas de animais acometidos clinicamente por doença respiratória e de animais ao abate. Avaliou-se 25 amostras de pulmão de 14 rebanhos obtidas de animais de terminação com sinais clínicos de doença respiratória aguda, e 19 pulmões coletados ao abate de 14 rebanhos diferentes. Em todos os pulmões, realizou-se isolamento bacteriano, e apenas amostras com crescimento puro de P. multocida foram incluídas no trabalho. Avaliou-se as lesões macro e microscopicamente, assim como co-infecções por Influenza A, Circovirus suíno tipo 2 (PCV2) e Mycoplasma hyopneumoniae. Pleurite e pericardite foram mais frequentemente observadas em amostras clinicas (P<0,05). Ainda, houve tendência numérica indicando a ocorrência de linfadenomegalia e exsudação cavitária, mais presentes em amostras clínicas. Treze amostras de pulmão foram negativas para M. hyopneumoniae, Influenza A e PCV2 por imunoistoquímica (IHQ), com identificação de apenas P. multocida. Nestes casos, lesões macroscópicas como pleurite, pericardite e linfadenomegalia foram sempre presentes, sem lesões histológicas indicativas de outros agentes como Actinobacillus pleuropneumoniae, Actinobacillus suis ou Haemophilus parasuis. Estes achados sugerem a habilidade de alguns isolados de P. multocida de causarem quadro respiratório primário e infecção sistêmica. No entanto, neste estudo, não foi possível determinar marcadores de virulência específicos para justificar tais achados.(AU)

High occurrence of Mycoplasma suis infection in swine herds from non-technified farms in Mossoró, state of Rio Grande do Norte, Northeastern Brazil / Alta ocorrência de infecção por Mycoplasma suis em suínos de criações não tecnificadas de Mossoró, estado do Rio Grande do Norte, Nordeste brasileiro

Abstract Mycoplasma suis, the etiological agent of swine hemoplasmosis, has been neglected in swine herds around the world. Swine hemoplasmosis is frequently associated with hemolytic anemia, disgalacty, infertility and immunosuppression, and it results in significant economic losses. This study investigates the occurrence of M. suis in non-technified swine herds in the northeastern region of Brazil using quantitative PCR (qPCR) based on the 16S rRNA gene. Between March and August 2013, blood samples from 147 swine were collected during slaughter in the city of Mossoró, state of Rio Grande do Norte, northeastern Brazil. One hundred and twelve samples (76.19%) were positive for M. suis by qPCR assays. The range of Cqs and quantification (copies of a M. suis-16S rRNA gene fragment/µL) was 20.8637.89 and 1.64×1016.64×107, respectively. One can conclude that M. suis infection have high occurrence (76,19%) in non-technified swine-rearing systems in Mossoró in the state of Rio Grande do Norte, Brazil.(AU)

Resumo Mycoplasma suis, agente etiológico da hemoplasmose suína, tem sido negligenciado nas criações de suínos ao redor do mundo. A hemoplasmose suína é frequentemente associada à anemia hemolítica, disgalactia, infertilidade e imunossupressão, acarretando em perdas econômicas. O objetivo do presente trabalho foi investigar, por meio da PCR quantitativa (qPCR) baseada no gene rRNA 16S, a ocorrência de M. suis em amostras de sangue de suínos de criações não tecnificadas na cidade de Mossoró, Estado do Rio Grande do Norte. Entre março a agosto de 2013, foram colhidas amostras de sangue de 147 suínos de criações não tecnificadas da referida região. Cento e doze amostras (76,19%) amostras mostraram-se positivas na qPCR para M. suis. A média dos Cqs e da quantificação (número de cópias do gene 16S rRNA de M. suis por microlitro) foi de 20,86 37,89 e 1,64 x 101 a 6,64 x 107, respectivamente. Conclui-se que a infecção por M. suis apresenta alta ocorrência (76,19%) em criações de suínos não tecnificadas na cidade de Mossoró, estado do Rio Grande do Norte.(AU)

Surveillance for Newcastle disease virus, Avian influenza virus and Mycoplasma gallisepticum in wild birds near commercial poultry farms surrounded by Atlantic rainforest remnants, Southeastern Brazil

The geographic overlap between areas of Atlantic rainforest and human activities allows interactions to occur between humans and wild and domestic animals. Despite the great importance of the domestic animal-wildlife-human interface that occurs at poultry farms in terms of public health, economic production and wildlife conservation, there are few studies in Brazil examining the distribution and health of wild birds that interact with poultry farms. From January to December 2010, mist nets were used to capture 166 free-ranging birds that were within close proximity to three poultry farms in Atlantic rainforest remnants in south-eastern Brazil. The species composition was examined, and molecular methods were used to test for avian influenza virus, Newcastle disease virus, and Mycoplasma gallisepticum. The avian communities near the poultry farms were dominated by three synanthropic species, which corresponded to 70% of all captured individuals: house sparrows Passer domesticus (33%), saffron finches (Sicalis flaveola) (22%), and ruddy ground-doves (Columbina talpacoti) (15%). These predominant bird species were in poor body condition (27%), were infested with feather mites (43%), or presented both conditions (23%). No evidence of infection by avian influenza virus, Newcastle disease virus or M. gallisepticum was identified in any of the studied birds. Although no evidence of the studied pathogens was, our findings demonstrate that differences in the environmental characteristics and biosecurity practices influence the wild bird community near poultry farms, which in turn may affect the health status of these synanthropic birds and strengthen their role in the transmission of pathogens.

Surveillance for Newcastle disease virus, Avian influenza virus and Mycoplasma gallisepticum in wild birds near commercial poultry farms surrounded by Atlantic rainforest remnants, Southeastern Brazil

The geographic overlap between areas of Atlantic rainforest and human activities allows interactions to occur between humans and wild and domestic animals. Despite the great importance of the domestic animal-wildlife-human interface that occurs at poultry farms in terms of public health, economic production and wildlife conservation, there are few studies in Brazil examining the distribution and health of wild birds that interact with poultry farms. From January to December 2010, mist nets were used to capture 166 free-ranging birds that were within close proximity to three poultry farms in Atlantic rainforest remnants in south-eastern Brazil. The species composition was examined, and molecular methods were used to test for avian influenza virus, Newcastle disease virus, and Mycoplasma gallisepticum. The avian communities near the poultry farms were dominated by three synanthropic species, which corresponded to 70% of all captured individuals: house sparrows Passer domesticus (33%), saffron finches (Sicalis flaveola) (22%), and ruddy ground-doves (Columbina talpacoti) (15%). These predominant bird species were in poor body condition (27%), were infested with feather mites (43%), or presented both conditions (23%). No evidence of infection by avian influenza virus, Newcastle disease virus or M. gallisepticum was identified in any of the studied birds. Although no evidence of the studied pathogens was, our findings demonstrate that differences in the environmental characteristics and biosecurity practices influence the wild bird community near poultry farms, which in turn may affect the health status of these synanthropic birds and strengthen their role in the transmission of pathogens.(AU)

OCORRÊNCIA E DIVERSIDADE GENÉTICA ASSOCIADA A INFECÇÃO POR MICOPLASMAS HEMOTRÓPICOS EM SUÍNOS DOMÉSTICOS NO BRASIL

Mycoplasma suis e Mycoplasma parvum se ligam fortemente aos eritrócitos e causam hemoplasmose em suínos. Os animais infectados podem ser portadores assintomáticos ou apresentar sinais inespecíficos, acometendo todas as faixas etárias. No Brasil, os estudos sobre a ocorrência e a diversidade genética associada aos hemoplasmas suínos (HS) são escassos. Portanto, este trabalho teve como objetivo detectar, quantificar e caracterizar a diversidade genética da HS em animais terminados de granjas tecnificadas no estado de Goiás, Brasil. Amostras de sangue total de 450 de 30 granjas diferentes localizadas no estado de Goiás, foram coletadas em tubos contendo ácido etilenodiaminotetracético (EDTA) e armazenadas a -80 °C. A extração de DNA seguiu o método in house descrito previamente. A PCR convencional (cPCR) direcionada ao gene endógeno gapdh foi realizada para evitar resultados falso-negativos nos testes seguintes. Os ensaios de PCR em tempo real quantitativa (qPCR) foram realizados a fim de detectar e quantificar DNA de Mycoplasma baseado no gene 16S rRNA para HS. Para avaliar a diversidade genética da HS, realizou-se a clonagem e sequenciamento dos genes 16S rRNA e 23S rRNA para hemoplasmas. Os resultados da qPCR mostraram uma ocorrência de HS de 68,89%, onde todas as fazendas tinham pelo menos dois animais positivos. A quantificação na qPCR variou de 8.43x10-1 a 4.69x106 µL, e 52.71% das amostras apresentaram 1x103 copies/µL. Além disso, o teste do coeficiente de Spearman revelou que a ocorrência de HS está inversamente associada ao número de partos por semana, leitões desmamados por semana e peso de abate. Já a análise filogenética utilizando os métodos de Máxima Verossimilhança e Bayesiana, demonstrou que os 22 clones obtidos a partir do fragmento 16S rRNA formaram um único cluster intimamente relacionado a M. parvum. Ainda, sete genótipos foram encontrados nas análises genéticas dessas 22 sequências, mesmo se tratando de um gene conservado. Análises filogenéticas por Máxima Verossimilhança e Bayesiana realizadas para os sete clones do fragmento 23S rRNA, resultaram em um clado associado a M. parvum (NR121958). Portanto, os resultados demonstram pela primeira vez a presença de M. parvum em suínos amostrados no estado de Goiás, e confirmam a existência de diferentes genótipos de M. parvum circulando entre granjas de suínos no Brasil.

Mycoplasma suis and Mycoplasma parvum are strongly bound to erythrocytes and cause hemoplasmosis in pigs. Infected animals can be asymptomatic carriers or have nonspecific signs, affecting all age groups. In Brazil, studies on the occurrence and genetic diversity associated with porcine hemoplasmas (PH) are scarce. Therefore, this work aimed to detect, quantify and characterize the genetic diversity of PH in finished animals from technified farms in the state of Goiás, Brazil. Whole blood samples from 450 animals from 30 different farms located in the state of Goiás, were collected in tubes containing ethylenediaminetetraacetic acid (EDTA) and stored at -80°C. DNA extraction followed the "in house" method previously described. Conventional PCR (cPCR) targeting the gapdh endogenous gene was performed to avoid false negative results in the following tests. Quantitative real-time PCR (qPCR) assays were performed in order to detect and quantify Mycoplasma DNA based on the 16S rRNA gene for PH. To assess the genetic diversity of PH, cloning and sequencing of the 16S rRNA and 23S rRNA genes for hemoplasmas was performed. The results of the qPCR showed a PH occurrence of 68.89%, where all farms had at least two positive animals. The quantification in the qPCR varied from 8.43x10-1 to 4.69x106 µL, and 52.71% of the samples presented 1x103 copies / µL. Furthermore, the Spearman coefficient test revealed that the occurrence of PH is inversely associated with the number of births per week, piglets weaned per week and slaughter weight. Phylogenetic analysis using the Maximum Likelihood and Bayesian methods, demonstrated that the 22 clones obtained from the 16S rRNA fragment formed a single cluster closely related to M. parvum. In addition, seven genotypes were found in the genetic analysis of these 22 sequences, even though it is a conserved gene. Phylogenetic analyzes by Maximum Likelihood and Bayesian performed for the seven clones of the 23S rRNA fragment, resulted in a clade associated with M. parvum (NR121958). Furthermore, the results demonstrate for the first time the presence of M. parvum in pigs sampled in the state of Goiás and confirm the existence of different genotypes of M. parvum circulating among pig farms in Brazil.

CARACTERIZAÇÃO PATOLÓGICA E BACTERIOLÓGICA DE LESÕES ARTICULARES EM SUÍNOS

Lesões articulares em suínos são frequentes e geralmente relacionadas a perdas econômicas para produtores e abatedouros. Artrites podem estar associadas a causas infecciosas e não infecciosas. Entre as artrite os agentes infecciosos mais comuns estão Erysipelothrix rhusiopathiae, Streptococcus suis, Glaesserella (Haemophilus) parasuis, Mycoplasma hyorhinis e Mycoplasma hyosynoviae, enquanto a osteocondrose é a causa não infecciosa mais importante em suínos. O objetivo deste estudo foi realizar a caracterização patológica e microbiológica de lesões articulares em suínos. As coletas foram efetuadas em dois frigoríficos no Estado do Rio Grande do Sul, Brasil. Um total de 8.808 suínos de 34 lotes foram examinados macroscopicamente durante o período do estudo. Cento e cinco lesões articulares foram coletadas, o que representou 1,19% dos suínos abatidos durante o período. As articulações femorotibiais direita e esquerda somadas foram as mais comumente envolvidas (39,04%), seguidas pelas articulações femorotibial direita (21,90%) e femorotibial esquerda (17,14%). Na microscopia, as lesões foram classificadas morfologicamente em sinovite linfoplasmocitica proliferativa (79,04%), sinovite associada com osteocondrose (12,38%) e sinovite fibrinonecrótica e supurativa (8,57%). Exame bacteriológico aeróbico foi realizado em todas as amostras coletadas. No entanto, o isolamento bacteriano foi raro e apenas 3,80% das amostras apresentaram crescimento com os métodos utilizados. As bactérias identificadas foram Streptococcus suis (1,90%), Streptococcus porcinus (0,95%) e Trueperella pyogenes (0,95%). No restante dos casos (96,19%), nenhum crescimento bacteriano significativo foi detectado. Portanto, o exame dos componentes articulares fornece informações sobre a natureza da lesão, diferenciando processos infecciosos de não-infecciosos. O exame de todas as articulações é importante para o diagnóstico mais preciso, bem como recomendase examinar mais de uma articulação quando a lesão macroscópica for evidenciada. O padrão histológico caracterizado como sinovite proliferativa linfoplasmacítica foi o mais frequentemente observado e análises moleculares são necessárias para definir a etiologia dessa lesão.

Joint injuries in swine are common and frequently related to economic losses for producers and meat industry. Arthritis may derive from infectious and non-infectious process. Among the most common infectious agents are Erysipelothrix rhusiopathiae, Streptococcus suis, Glaesserella parasuis (Haemophilus) parasuis, Mycoplasma hyorhinis, and Mycoplasma hyosynoviae, while osteochondrosis is the non-infectious cause more important to swine. The objective of this study was to perform a pathological and microbiological characterization of articular lesions in swine. Articular lesions were collected in two slaughterhouses in the state of Rio Grande do Sul, Brazil. A total of 8,808 pigs out of 34 batches were examined during the study period. One hundred five joint injuries were collected, which represented 1.19% of the amount of slaughtered pigs during the study period. The right and left femorotibial joints alongside were the most affected articulations (39.04%), followed by right femorotibial (21.90%), and left femorotibial joint with (17.14%). The lesions observed were classified according to their morphology as lymphoplasmacytic proliferative synovitis (79.04%), synovitis associated with osteochondrosis (12.38%), and fibrinonecrotic and suppurative synovitis (8.57%). Aerobic bacterial culture was performed in all samples collected. However, bacterial isolation was rare and only 3.80% (4/105) samples showed growth with the methods used. The bacteria isolated were Streptococcus suis (1.90%), Streptococcus porcinus (0.95%), and Trueperella pyogenes (0.95%). In the rest of the cases (96.19%), no significant bacterial growth or no bacterial growth was noticed. Therefore, the examination of the articular structures provides insights into the nature of the lesion, differentiating between infectious and non-infectious lesions. Besides, the examination of all joints may be necessary to diagnosis more precisely. It is recommended to evaluate all joints when macroscopic alteration is found noticed in one. The histopathologic pattern of lymphoplasmacytic proliferative synovitis were the most frequently seen and molecular analysis is necessary to define the etiology of this lesion.

Mycoplasma Suis HEMOTRÓFICO NO ESTADO DE SÃO PAULO: EPIDEMIOLOGIA E HEMATOLOGIA

A hemoplasmose dos suínos, causada pelo Mycoplasma suis, caracteriza-se como doença geograficamente cosmopolita, atinge animais de diversas faixas etárias, frequentemente associada à anemia hemolítica moderada a grave e predispõe os animais a imunossupressão, infertilidade, diminuição do ganho de peso, aumento de natimortos, abortos e retorno ao cio, ou seja, impacta diretamente as granjas de suínos e leva a imensuráveis perdas econômicas. Do ponto de vista epidemiológico, animais assintomáticos são considerados como foco da hemoplasmose por serem portadores e apresentarem melhora clínica sem a eliminação do parasita e alguns autores reportam a micoplasmose hemotrófica como uma enfermidade de potencial zoonótico. A prevalência nos rebanhos brasileiros é discutível, especialmente por que o diagnóstico tradicional pela observação do M. suis no esfregaço sanguíneo tem baixa sensibilidade. Objetivou-se com o presente trabalho caracterizar a taxa de prevalência e correlacionar a quantidade do Mycoplasma suis quantificado por qPCR com alterações nos parâmetros hematológicos em suínos em diferentes fases de criação de granjas tecnificadas de ciclo completo do Estado de São Paulo. Foram avaliadas 20 diferentes granjas suinícolas de ciclo completa situadas em território paulista, foram coletadas 501 amostras de sangue total em EDTA-K2 para análise molecular de qPCR para Mycoplasma suis e realização de hemograma e pesquisa de hemoparasitas em esfregaço sanguíneo. No primeiro capítulo realizou-se uma revisão de literatura sobre o Mycoplasma suis, a patobiologia do agente bem como os sinais clínicos nos animais. No capítulo 2 relatou-se a ocorrência do Mycoplasma suis nas granjas tecnificadas de ciclo completo no Estado de São Paulo e foi possível determinar uma prevalência total de animais infectados de 31,93% (161/201) e 95% (19/20) de granjas infectados e por fase de criação foram: creche (30,47%); recria (31,29%), teminação (26,18%) e frigorífico (40,25%). No terceiro capítulo, correlacionou-se os resultados dos parâmetros hematológicos com a bacteremia de M suis, sendo que, na comparação dos hemogramas de animais positivos e negativos não houve diferença estatística e ambos os grupos não apresentavam valores alterações em relação aos valores referenciais adotados, situação na qual evidencia-se a condição de animais portadores, aparentemente sadios que auxiliam na permanência e propagação do agente nos rebanhos. Nos animais positivos foram observadas correlação entre hemoglobina (y = 9,978 + 0,186 x, p = 0,02, r²=0,354), plaquetas (y = 582,522 16,190 x, p = 0,04, r² = 0,286) e neutrófilos (y = 9,77 0,307 x, p = 0,05, r² = 0,276) com a bacteremia de M suis, esses resultados indicam a presença de hemólise, dano vascular e consumo plaquetário inerente aos animais portadores da micoplasmose hemotrófica.

Porcine hemoplasmosis caused by Mycoplasma suis, is characterized as a geographically cosmopolitan disease. It affects animals of various age groups, often associated with moderate to severe hemolytic anemia and predisposes the animals to immunosuppression, infertility, decreased weight gain, increased stillbirths, miscarriages and return to heat, that is, directly impacts pig farms and leads to immeasurable economic losses. From an epidemiological point of view, asymptomatic animals are considered as the focus of hemoplasmosis because they are carriers and present clinical improvement without the elimination of the parasite and some authors report hemotrophic mycoplasmosis as a zoonotic potential disease. The prevalence in Brazilian herds is debatable, especially since the traditional diagnosis by observing M suis in the blood smear has low sensitivity. The objective of this study was to characterize the prevalence rate and correlate the quantity of Mycoplasma suis quantified by qPCR with changes in hematological parameters in pigs in different phases of rearing of full-cycle farms in the State of São Paulo. Twenty different complete cycle swine farms located in the state of São Paulo were evaluated, 501 whole blood samples were collected in EDTA-K2 for molecular analysis of qPCR for Mycoplasma suis and blood count and blood smear hemoparasites. In the first chapter there was a literature review on Mycoplasma suis, the pathobiology of the agent as well as clinical signs in animals. In Chapter 2, the occurrence of Mycoplasma suis was reported in the full-cycle technicated farms in the State of São Paulo and it was possible to determine a total prevalence of infected animals of 31.93% (161/201) and 95% (19/20) infected farms and by growth stages were: nursery (30.47%); growing (31.29%), finishing (26.18%) and slaughter (40.25%). In Chapter 3, the results of the hematological parameters were correlated with the M suis bacteremia, and in the comparison of the blood counts of positive and negative animals there was no statistical difference and both groups did not present alterations values in relation to the adopted reference values. This situation evidences the condition of apparently healthy carriers that help in the permanence and propagation of the agent in the herds. In positive animals, a correlation was observed between hemoglobin (y = 9.978 + 0.186 x, p = 0.02, r² = 0.354), platelets (y = 582.522 - 16.190 x, p = 0.04, r² = 0.286) and neutrophils (y = 9.77 - 0.307 x, p = 0.05, r² = 0.276) with M suis bacteremia, these results indicate the presence of hemolysis, vascular damage and platelet consumption inherent in animals with hemotrophic mycoplasmosis.

Pericardite em suínos ao abate no Rio Grande Sul: avaliação de agentes bacterianos e lesões associadas / Bacterial agents and lesions associated with pericarditis in slaughter pigs in Rio Grande do Sul, Brazil

O objetivo do presente estudo foi identificar a frequência de lesões macroscópicas e microscópicas e dos agentes bacterianos envolvidos em pericardites em suínos no abate no Estado do Rio Grande do Sul. As amostras foram coletadas em frigoríficos de suínos com Serviço de Inspeção Federal (SIF) entre fevereiro a outubro de 2010 e a condenação por pericardite dos animais acompanhados foi de 3,9 por cento(299/7.571). No total foram investigados 91 casos de pericardites, 89% deles foram classificados como crônicos por histopatologia e pleurite crônica foi observada em 47 porcento dos pulmões correspondentes, todavia não houve associação significativa entre as duas lesões. Os agentes bacterianos isolados a partir dos corações foram Streptococcus spp., Pasteurella multocida, Haemophilus parasuis e Streptococcus suis. DNA bacterianos mais detectados pela PCR foram de Mycoplasma hyopneumoniae e Actinobacillus pleuropneumoniae. Houve associação significativa entre isolamento de P. multocida e Streptococcus sp. nos corações e pulmões correspondentes. Esses resultados sugerem que a infecção no pulmão possa ter servido de porta de entrada para a colonização do pericárdio adjacente. Apesar de M. hyopneumoniae ter sido o agente detectado com maior frequência pela PCR em corações e pulmões correspondentes, não houve associação significativa da detecção dos agentes nos órgãos. Isto sugere que as infecções foram eventos independentes. Os demais agentes investigados não apresentaram associação significativa entre isolamento ou detecção de DNA em coração e pulmão correspondente. Outro achado importante foi a presença de coinfecções bacterianas em 2 por cento dos corações e por PCR foi detectado DNA bacteriano de dois ou mais agentes em 16,5 por cento dos corações. Esses resultados sugerem que as coinfecções em pericardites precisam ser melhor estudadas.(AU)

The objective of the study was to identify the frequency of macroscopic and microscopic lesions and bacterial agents involved with pericarditis in slaughter pigs in the State of Rio Grande do Sul, Brazil. The samples were collected in slaughterhouses with Federal Inspection Service (SIF) between February and October, 2010. Condemnation due to pericarditis in the examined animals was 3.9 percent (299/7,571). Ninety one cases of pericarditis were examined and by histopathology 89% were chronic and 47 percent of the corresponding lungs showed chronic pleuritis, but there was no significant association between both lesions. The bacterial agents isolated from the hearts were Streptococcus spp., Pasteurella multocida, Haemophilus parasuis and Streptococcus suis. Bacterial DNA from Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae were the most frequently detected by PCR. There was significant association between isolation of P. multocida and Streptococcus spp. in the hearts and corresponding lungs. The results suggest that lung infection could act as a port of entry to the colonization of the adjacent pericardium. In spite of the fact that M. hyopneumoniae was the agent more frequently identified by PCR in the heart and corresponding lung, there was no significant association of the agent in the organs. This suggests that the infections were independent events. The other agents investigated did not show significant association between isolation or DNA detection in heart and corresponding lungs. Another important finding was the presence of coinfection between bacterial agents in 2 percent of the hearts and by PCR were identified bacterial DNA of two or more agents in 16.5 percent of the hearts. These results suggest that coinfections in cases of pericarditis need further investigation.(AU)

Findings of antibodies to Mycoplasma suis on swine farms in Serbia / Findings of antibodies to Mycoplasma suis on swine farms in Serbia

Background: Hemoplasmas are eperythrocytic procaryotes, including Mycoplasma species which were recently transferred from the genera Eperythrozoon and Haemobartonella, based on their similarity of the 16S rRNA sequences, and newly identified hemotropic mycoplasmas. Eperythrozoonosis of pigs is caused by the haemotrophic bacterium M. suis, and the disease has a worldwide distribution. The disease manifests as a severe and often fatal acute febrile icteroanemia, mainly in piglets, pregnant sows before parturition and fattening pigs exposed to stress. The aim of this study was to determine the seroprevalence of IgG to M. suis in swine populations in Serbia, using a Western Blot test with the recombinant protein MSG1. Materials, Methods & Results: Four farms were chosen to represent the main swine-producing geographic regions of Serbia, including South Baka District (farms 1 and 2), North Baka District (farm 3) and Branievo District (farm 4). A total of forty-six clinically healthy pigs, age 8-20 weeks, were included in the study. Blood samples from pigs randomly selected from the four farms were collected by jugular vein puncture into serum vacutainer tubes with clot activator. After clotting at room temperature for 1 h, blood samples were centrifuged at 1500 g, for 15 min at room temperature. Sera were carefully harvested and stored at -20C until assayed. The sera samples

Background: Hemoplasmas are eperythrocytic procaryotes, including Mycoplasma species which were recently transferred from the genera Eperythrozoon and Haemobartonella, based on their similarity of the 16S rRNA sequences, and newly identified hemotropic mycoplasmas. Eperythrozoonosis of pigs is caused by the haemotrophic bacterium M. suis, and the disease has a worldwide distribution. The disease manifests as a severe and often fatal acute febrile icteroanemia, mainly in piglets, pregnant sows before parturition and fattening pigs exposed to stress. The aim of this study was to determine the seroprevalence of IgG to M. suis in swine populations in Serbia, using a Western Blot test with the recombinant protein MSG1. Materials, Methods & Results: Four farms were chosen to represent the main swine-producing geographic regions of Serbia, including South Baka District (farms 1 and 2), North Baka District (farm 3) and Branievo District (farm 4). A total of forty-six clinically healthy pigs, age 8-20 weeks, were included in the study. Blood samples from pigs randomly selected from the four farms were collected by jugular vein puncture into serum vacutainer tubes with clot activator. After clotting at room temperature for 1 h, blood samples were centrifuged at 1500 g, for 15 min at room temperature. Sera were carefully harvested and stored at -20C until assayed. The sera samples

Findings of antibodies to Mycoplasma suis on swine farms in Serbia

Background: Hemoplasmas are eperythrocytic procaryotes, including Mycoplasma species which were recently transferred from the genera Eperythrozoon and Haemobartonella, based on their similarity of the 16S rRNA sequences, and newly identified hemotropic mycoplasmas. Eperythrozoonosis of pigs is caused by the haemotrophic bacterium M. suis, and the disease has a worldwide distribution. The disease manifests as a severe and often fatal acute febrile icteroanemia, mainly in piglets, pregnant sows before parturition and fattening pigs exposed to stress. The aim of this study was to determine the seroprevalence of IgG to M. suis in swine populations in Serbia, using a Western Blot test with the recombinant protein MSG1. Materials, Methods & Results: Four farms were chosen to represent the main swine-producing geographic regions of Serbia, including South Backa District (farms 1 and 2), North Backa District (farm 3) and Branicevo District (farm 4). A total of forty-six clinically healthy pigs, age 8-20 weeks, were included in the study. Blood samples from pigs randomly selected from the four farms were collected by jugular vein puncture into serum vacutainer tubes with clot activator. After clotting at room temperature for 1 h, blood samples were centrifuged at 1500 g, for 15 min at room temperature. Sera were carefully harvested and stored at -20°C until assayed. The sera samples were tested by the Western Blot test with recombinant protein MSG1 (p40). Production of recombinant protein MSG1 (p40), dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting were performed as previously described by Hoelzle. Specific IgG antibodies to MSG1 of M. suis were identified in 20 of the 46 samples tested, giving a total seroprevalence of 43.47%. The M. suis-specific antibody response was detected in pigs from all tested farms, within farm seroprevalences of 54.54% on farm 1; 27.27% on farm 2; 36.36% on farm 3 and 53.84% on farm 4. Discussion: Reports on the prevalence of swine infected with Mycoplasma suis in other countries are rare, but have been communicated for USA, Brazil, Japan, Portugal, China and Germany. Previously published values of the prevalence of the pigs infected with haemoplasmas in Serbia, determined through a microscopic examination of the peripheral blood smear according to Giemsa was 39% and with Acridine orange was 47%. These prevalences are similar to the overall prevalence found in this study (43.47%). In this present study, the prevalence of M. suis in the farm pigs studied in Serbia (43.47%) was higher than the serological evidence of the infection reported in pigs in the USA, Brazil and Japan, but lower than the prevalence in sows in Portugal and China. In this present study, the prevalence of M. suis on the studied pig farms in Serbia (43.47%) was more similar to results obtained in Germany, where M. suis infections were detected in 79 out of 196 pig farms (40.3%) by employing a quantitative real-time LightCycler PCR. Also, M. suis was detected in 36 out of 359 wild German boars (10.03%) with similar methodology. Our seroprevalence of anti-M. suis IgG in farmed pigs is probably higher than that in wild boar because of the conditions of intensive breeding on pig farms, but perhaps this may also be partly due to the different geographic locality, and/or to different analytical methods. This overall determined seroprevalence of 43.47% from a small sample within a relatively small area suggests a signifi cantly higher presence of infection on pig farms in Serbia, and hence, significantly more economic losses in pig production than could be expected based on the worldwide reports of M. suis prevalence.