PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Santos S.B., Nascimento E.R., Faccini J.L.H., Barreto M.L. & Mota R.A. 2012. [Mycoplasmas species associated with the ear mites in cattle.] Associação entre Mycoplasma spp. e ácaros do conduto auditivo de bovinos. Pesquisa Veterinária Brasileira 32(4):293-296. Laboratório de Bacterioses dos Animais Domésticos, Departamento de Medicina Veterinária, Universidade Federal Rural de Pernambuco, Av. Dom Manoel de Medeiros s/n, Recife, PE 52171-900, Brazil. E-mail: sanbsantos@gmail.com This study was carried out to assess the association between of mycoplasmas species with ear mites Raillietia auris and R. flechtmanni in the external ear canal of 60 bovines at slaughter time from the State of Rio de Janeiro, Brazil. Steril syringes (60ml) loaded with buffer solution (PBS, pH 7.2) were used for the ear canal flushing. Were processed 218 mites for mycoplasma isolation. A pool of mites from each sampled bovine was washed five times sucessively in 1mL of liquid modified Hayflick´s medium. The washed mites obtained were diluted up to 10-1 at 10-5, inoculated in liquid and solid Hayflick´s media and incubated at 37oC for 2-3 days, being the plates put into jar for the obtention of microaerofilia condition. The Typical colonies were typified by the indirect imunoperoxidase test (IPI) with paper discs satured with hyperimmune rabbit sera. In the studied bovine high prevalence was verified Raillietia spp. 76.7% (46/60). The parasitism by mycoplasmas and mites was verified in 40 animals (74.1%), this association was significant (p<0.001). Among the mites processed for isolation mycoplasmas 193 were female and 25 males. The frequency of Mycoplasma in Raillietia spp. was of 81.2% (177/218) (p<0.001). Of the females identified 52.3% (101/193) were R. auris and 47.7% (92/193) were R. flechtmanni. The frequency of Mycoplasma in the females of R. auris was of 75.2% (76/101) and 88% (81/92) in R. flechtmanni (P<0.05). The mycoplasmas species typified by IPI in the Raillietia auris mites were M. alkalescens 6.9%, M. arginini 3.4%, M. bovirhinis 9.2%, M. conjunctivae 18.4%, M. mycoides mycoides LC 8.0%, M. capricolum 5.7%. In the R. flechtmanni mites mycoplasmas species typified were M. alkalescens 12.2%, M. arginini 1.0%, M. bovirhinis 18.9%, M. bovis 2.2%, M. conjunctivae 21.0%, M. mycoides mycoides LC 11.0% e M. capricolum 4.4%. The species of identified mycoplasmas in the external ear canal bovine and mites were exactly the same. The results confirm that the external ear canal cattle’s ear canal is also a mycoplasmas source, including potentially pathogenic species for cattle, and these mollicutes are closely related with mites Raillietia spp. that is carrier and this agent in your organism.

• Mycoplasma spp ear mites Gamasida ácaros Gamasida

Abstract in Portuguese:

RESUMO.- Santos S.B., Nascimento E.R., Faccini J.L.H., Barreto M.L. & Mota R.A. 2012. [Mycoplasmas species associated with the ear mites in cattle.] Associação entre Mycoplasma spp. e ácaros do conduto auditivo de bovinos. Pesquisa Veterinária Brasileira 32(4):293-296. Laboratório de Bacterioses dos Animais Domésticos, Departamento de Medicina Veterinária, Universidade Federal Rural de Pernambuco, Av. Dom Manoel de Medeiros s/n, Recife, PE 52171-900, Brazil. E-mail: sanbsantos@gmail.com Esse estudo foi realizado com o objetivo de verificar a associação entre micoplasmas e ácaros (Raillietia auris e R. flechtmanni) no conduto auditivo de bovinos. Foram realizadas lavagens no conduto auditivo externo de 60 bovinos abatidos no Estado do Rio de Janeiro, Brasil. Para a lavagem dos condutos auditivos foi utilizada solução salina tamponada (PBS, pH 7.2) em seringas estéreis de 60mL. Para o isolamento de micoplasmas foram utilizados pools de ácaros por animal, lavados sucessivamente em 1mL de meio Hayflick modificado. Os lavados dos ácaros foram diluídos de 10-1 até 10-5 e repicados em meio Hayflick modificado, sólido e líquido e incubados a 37°C por 48-72 horas em microaerofilia. A identificação das espécies de micoplasmas foi realizada pelo teste da imunoperoxidase indireta (IPI). Verificou-se alta prevalência de ácaros do gênero Raillietia spp. 76,7% (46/60). O parasitismo por ácaros e micoplasmas foi verificado em 40 animais (74,1%), sendo esta associação significativa (p<0,001). Dos ácaros processados para isolamento de micoplasmas, 193 foram fêmeas e 25 machos. A frequência de Mycoplasma em Raillietia spp. foi de 81,2% (177/218) (p<0.001). Das fêmeas identificadas, 52,3% (101/193) foram R. auris e 47,7% (92/193) R. flechtmanni. A frequência de Mycoplasma nas fêmeas de R. auris foi de 75,2% (76/101) e na espécie R. flechtmanni foi de 88% (81/92) (P<0.05). As espécies de micoplasmas tipificadas pela IPI nos ácaros Raillietia auris foram: M. alkalescens 6,9%, M. arginini 3,4%, M. bovirhinis 9,2%, M. conjunctivae 18,4%, M. mycoides mycoides LC 8,0%, M. capricolum 5,7%. Em R. flechtmanni as espécies de micoplasmas identificadas foram: M. alkalescens 12,2%, M. arginini 1,0%, M. bovirhinis 18,9%, M. bovis 2,2%, M. conjunctivae 21,0%, M. mycoides mycoides LC 11,0% e M. capricolum 4,4%. As espécies de micoplasmas identificadas no conduto auditivo externo dos bovinos foram as mesmas presentes nos ácaros R. auris e R. flechtmanni. Os resultados confirmam que o conduto auditivo externo de bovinos é um habitat de Mycoplasma spp., incluindo espécies potencialmente patogênicas para os rebanhos, além dos ácaros R. auris e R. flechtmanni estarem associados com esses molicutes carreando-os em seu organismo.

Abstract in English:

ABSTRACT.- Santos S.B., Nascimento E.R., Faccini J.L.H., Barreto M.L., Almeida J.F., Pereira V.L.A. & Campos C.A.M. 2010. [Detection of Mycoplasma mycoides cluster by indirect immunoperoxidase (IPI) and PCR-REA in the ear canal of bovines.] Detecção do Grupo Mycoplasma mycoides por imunoperoxidase indireta (IPI) e PCR-REA em conduto auditivo de bovinos. Pesquisa Veterinária Brasileira 30(5):465-469. Departamento de Saúde Coletiva Veterinária e Saúde Pública, Universidade Federal Fluminense, Rua Vital Brazil Filho 64, Niterói, RJ 24230-340, Brazil. E-mail: elmiro@vm.uff.br Mycoplasma mycoides cluster (MMC) was diagnosed by polimerase chain reaction-restriction endonuclease analysis (PCR-REA) and indirect immunoperoxidase (IPI), both, carried out in flushing from external ear canal, collected from bovine at slaughter time in the State of Rio de Janeiro, southeastern, Brazil. A total of 60 bovines were randomly selected. Sterile syringes (60mL) loaded with buffer solution (PBS, pH 7.2) were used for the ear canal flushing. The obtained samples were stored in glycerol (1:2) and frozen at -20oC until use. These specimens were diluted up to 10-5, inoculated in liquid and solid modified Hayflick´s media and incubated at 37oC for 2-3 days. The plates were kept in a microaerophilia condition and examined every two days under a stereomicroscope for the presence of typical colonies “fried-egg”. In this study, 35 strains selected in agreement with their biochemistry and physiologic proprieties, were used. From the 60 cultivated samples, 48 (80.00%) were positive for Mycoplasma spp. Under IPI the prevalence obtained for MMC was 20.0% (12/60) while by PCR-REA it was 41.7% (25/60). The IPI typing of these isolates resulted in 58.3% (7/12) for M.mycoides mycoides LC and 41.7% (5/12) for M. capricolum. PCR-REA for MMC was confirmed by the amplicon size of 785bp, compatible with this group. The Kappa value for the association between these two tests was 0.14 (p>0.05). After restriction analysis with AluI in all MMC strains the fragments size obtained were of 81, 98, 186 and 236bp, but not of 370bp that is compatible with Mycoides mycoides mycoides SC of bovine type. The presence of mycoplasmas species in the ear canal of asymptomatic bovines represent a risk of subsequent propagation of Mycoplasma spp. among bovine herds in Brazil.

• Mycoplasma mycoides

Abstract in Portuguese:

RESUMO.- Santos S.B., Nascimento E.R., Faccini J.L.H., Barreto M.L., Almeida J.F., Pereira V.L.A. & Campos C.A.M. 2010. [Detection of Mycoplasma mycoides cluster by indirect immunoperoxidase (IPI) and PCR-REA in the ear canal of bovines.] Detecção do Grupo Mycoplasma mycoides por imunoperoxidase indireta (IPI) e PCR-REA em conduto auditivo de bovinos. Pesquisa Veterinária Brasileira 30(5):465-469. Departamento de Saúde Coletiva Veterinária e Saúde Pública, Universidade Federal Fluminense, Rua Vital Brazil Filho 64, Niterói, RJ 24230-340, Brazil. E-mail: elmiro@vm.uff.br O Grupo Mycoplasma mycoides (GMM) foi diagnosticado por PCR-REA e imunoperoxidase indireta (IPI) em amostras de lavados de conduto auditivo de bovinos no Estado do Rio de Janeiro, Brasil. 60 bovinos foram selecionados aleatoriamente. As lavagens foram feitas com uso de seringas estéreis contendo um volume de 60 mL de solução salina tamponada (PBS pH 7.2). As amostras obtidas foram estocadas em glicerol (1:2) e congeladas a -20oC até uso. Estas amostras foram diluídas até 10-5 e repicadas em meio Hayflick modificado, sólido e líquido, sendo incubados a 37oC por 48-72 horas. As placas foram mantidas em microaerofilia e observadas diariamente, para visualização das colônias típicas em “ovo-frito”. Das 60 amostras cultivadas, 48 (80,00%) foram positivas para Mycoplasma spp. A prevalência obtida para o GMM na IPI foi de 20,0% (12/60) enquanto na PCR-REA foi de 41,7% (25/60). Das cepas tipificadas pela IPI 58,3% (7/12) foram M. mycoides subsp. mycoides LC e 41,7% (5/12) foram M. capricolum. Na PCR-REA o grupo M. mycoides foi confirmado pela visualização de um amplicon de 785bp, compatível com este grupo. O valor encontrado no teste Kappa para associação entre estes testes foi de 0,14 (P>0,05. Na clivagem do produto da PCR com a enzima de restrição AluI, de cepas de referências e dos isolados de ouvido os fragmentos obtidos foram de 81, 98, 186 e 236pb, mas não de 370pb, que é específica para o agente da Pleuropneumonia Contagiosa Bovina. A presença de espécies de micoplasmas no conduto auditivo de bovinos assintomáticos representa um risco para propagação de Mycoplasma spp. entre rebanhos bovinos no Brasil.

Abstract in English:

ABSTRACT.- Buim M.R., Mettifogo E., Timenetsky J., Kleven S. & Ferreira A.J.P. 2009. Epidemiological survey on Mycoplasma gallisepticum and M. synoviae by multiplex PCR in commercial poultry. Pesquisa Veterinária Brasileira 29(7):552-556. Departamento de Patologia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP 05508-900, Brazil. E-mail: ajpferr@usp.br Mycoplasmas are important avian pathogens, which cause respiratory and joint diseases that result in large economic losses in Brazilian and world-wide poultry industry. This investigation regarding the main species of mycoplasmas, Mycoplasma gallisepticum (MG) and M. synoviae (MS), responsible for the above mentioned conditions, was carried out through PCR Multiplex analysis. One thousand and forty-six (1,046) samples of tracheal swabs and piped embryos were collected from 33 farms with laying hens, breeders, broilers or hatchery, located in the Brazilian states of São Paulo, Paraná and Pernambuco, where respiratory problems or drops in egg production had occurred. The MG and MS prevalence on the farms was 72.7%. These results indicated (1) high dissemination of mycoplasmas in the evaluated farms, with predominance of MS, either as single infectious agent or associated with other mycoplasmas in 20 farms (60.6%), and (2) an increase of MS and decrease of MG infection in Brazilian commercial poultry.

• Mycoplasma gallisepticum M. synoviae PCR epidemiology chicken

Abstract in Portuguese:

ABSTRACT.- Buim M.R., Mettifogo E., Timenetsky J., Kleven S. & Ferreira A.J.P. 2009. Epidemiological survey on Mycoplasma gallisepticum and M. synoviae by multiplex PCR in commercial poultry. Pesquisa Veterinária Brasileira 29(7):552-556. Departamento de Patologia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP 05508-900, Brazil. E-mail: ajpferr@usp.br Mycoplasmas are important avian pathogens, which cause respiratory and joint diseases that result in large economic losses in Brazilian and world-wide poultry industry. This investigation regarding the main species of mycoplasmas, Mycoplasma gallisepticum (MG) and M. synoviae (MS), responsible for the above mentioned conditions, was carried out through PCR Multiplex analysis. One thousand and forty-six (1,046) samples of tracheal swabs and piped embryos were collected from 33 farms with laying hens, breeders, broilers or hatchery, located in the Brazilian states of São Paulo, Paraná and Pernambuco, where respiratory problems or drops in egg production had occurred. The MG and MS prevalence on the farms was 72.7%. These results indicated (1) high dissemination of mycoplasmas in the evaluated farms, with predominance of MS, either as single infectious agent or associated with other mycoplasmas in 20 farms (60.6%), and (2) an increase of MS and decrease of MG infection in Brazilian commercial poultry.

Abstract in English:

ABSTRACT.- Ecco R., Lazzari M.A. & Guedes R.M.C. 2009. [Enzootic pneumonia in wild boars (Sus scrofa).] Pneumonia enzoótica em javalis (Sus scrofa). Pesquisa Veterinária Brasileira 29(6):461-468. Departamento de Clinica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Cx. Postal 567, Belo Horizonte, MG 31270-901, Brazil. E-mail: ecco@vet.ufmg.br The aim of this paper is to describe the clinical, epidemiological, pathological, bacteriological and immunohistochemical aspects of a pneumonia outbreak in a wild pig farm in the Distrito Federal, Brazil. Ninety wild pigs died in a period of five months, and 63 of these had pulmonary lesions. Clinically, the pigs presented reduced growth rate, anorexia, lethargy, cough and dyspnea, especially after they were moved. High body temperature (40oC in average) was verified in some animals. Auscultation revealed moderate pulmonary crepitation and stertors. Pulmonary gross lesions were typical of lobular bronchopneumonia. Lung lesions were characterized by ventral-cranial consolidation in the majority of the cases. The color of affected pulmonary areas varied from diffuse dark red to mosaic pattern (dark red lobule intercalate by grayish lobule) or diffusely grayish. The majority of the lungs had mucopurulent exsudate in the bronchial lumen that also drained from the parenchyma cut surface. Upon microscopy, the changes were characterized by purulent and histiocytic bronchopneumonia with necrotic foci. In some animals, there was BALT hyperplasia associated with perivascular and peribronchial plasma cells and lymphocytes infiltration in most of these cases. Bordetella bronchiseptica and Streptococcus spp. were the most frequently isolated bacteria. Immunohistochemistry evaluation demonstrated Mycoplasma hyopneumoniae on the luminal surface of bronchial and bronchiolar epithelial cells, and the DNA of bacteria was detected by PCR. This is the first report of bronchopneumonia in wild boars associated with M. hyopneumoniae infection.

• Wild pigs bronchopneumonia pathology bacteriology PCR immunohisto-chemistry Mycoplasma hyopneumoniae

Abstract in Portuguese:

ABSTRACT.- Ecco R., Lazzari M.A. & Guedes R.M.C. 2009. [Enzootic pneumonia in wild boars (Sus scrofa).] Pneumonia enzoótica em javalis (Sus scrofa). Pesquisa Veterinária Brasileira 29(6):461-468. Departamento de Clinica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Cx. Postal 567, Belo Horizonte, MG 31270-901, Brazil. E-mail: ecco@vet.ufmg.br The aim of this paper is to describe the clinical, epidemiological, pathological, bacteriological and immunohistochemical aspects of a pneumonia outbreak in a wild pig farm in the Distrito Federal, Brazil. Ninety wild pigs died in a period of five months, and 63 of these had pulmonary lesions. Clinically, the pigs presented reduced growth rate, anorexia, lethargy, cough and dyspnea, especially after they were moved. High body temperature (40oC in average) was verified in some animals. Auscultation revealed moderate pulmonary crepitation and stertors. Pulmonary gross lesions were typical of lobular bronchopneumonia. Lung lesions were characterized by ventral-cranial consolidation in the majority of the cases. The color of affected pulmonary areas varied from diffuse dark red to mosaic pattern (dark red lobule intercalate by grayish lobule) or diffusely grayish. The majority of the lungs had mucopurulent exsudate in the bronchial lumen that also drained from the parenchyma cut surface. Upon microscopy, the changes were characterized by purulent and histiocytic bronchopneumonia with necrotic foci. In some animals, there was BALT hyperplasia associated with perivascular and peribronchial plasma cells and lymphocytes infiltration in most of these cases. Bordetella bronchiseptica and Streptococcus spp. were the most frequently isolated bacteria. Immunohistochemistry evaluation demonstrated Mycoplasma hyopneumoniae on the luminal surface of bronchial and bronchiolar epithelial cells, and the DNA of bacteria was detected by PCR. This is the first report of bronchopneumonia in wild boars associated with M. hyopneumoniae infection.

Abstract in English:

Portiansky E.L., Quiroga M.A., Machuca M.A. & Perfumo C.J. 2004. Mycoplasma suis in naturally infected pigs: an ultrastructural and morphometric study. Pesquisa Veterinária Brasileira 24(1):1-5. Instituto de Patología, Faculdad de Ciencias Veterinarias, Universidad Nacional de La Plata, Calle 60 y 118, C.C. 296, (1900) La Plata, Buenos Aires, Argentina. E-mail: elporti@fcv.unlp.edu.ar Swine eperythrozoonosis is a haemotrophic disease caused by Eperythrozoon suis, actually called Mycoplasma suis, an extracellular bacterial organism that apparently adheres to pig erythrocyte membrane, inducing its deformation and damage. Since little is known about the ultrastructural and morphometrical aspects of this microorganism, the present work aimed to deal with these issues. The ultrastructural study revealed the presence of structures corresponding to tubules disseminated throughout the soma of M. suis. A variable separation between the microorganism membrane and that of the erythrocyte was also observed. The structural and positional attitude of M. suis could allow speculation about its mechanism of action.

• Eperythrozoonosis Mycoplasma suis ultrastructure morphometry pathogenesis.

Abstract in Portuguese:

Portiansky E.L., Quiroga M.A., Machuca M.A. & Perfumo C.J. 2004. Mycoplasma suis in naturally infected pigs: an ultrastructural and morphometric study. Pesquisa Veterinária Brasileira 24(1):1-5. Instituto de Patología, Faculdad de Ciencias Veterinarias, Universidad Nacional de La Plata, Calle 60 y 118, C.C. 296, (1900) La Plata, Buenos Aires, Argentina. E-mail: elporti@fcv.unlp.edu.ar Swine eperythrozoonosis is a haemotrophic disease caused by Eperythrozoon suis, actually called Mycoplasma suis, an extracellular bacterial organism that apparently adheres to pig erythrocyte membrane, inducing its deformation and damage. Since little is known about the ultrastructural and morphometrical aspects of this microorganism, the present work aimed to deal with these issues. The ultrastructural study revealed the presence of structures corresponding to tubules disseminated throughout the soma of M. suis. A variable separation between the microorganism membrane and that of the erythrocyte was also observed. The structural and positional attitude of M. suis could allow speculation about its mechanism of action.

Abstract in English:

ABSTRACT.- Pretto L.G., Müller E.E., Freitas J.C., Mettifogo E., Buzinhani M., Yamaguti M. & Salvador R. 2001. [Mastitis caused by Mycoplasma bovis in dairy cattle] Mastite bovina por Mycoplasma bovis em rebanhos leiteiros. Pesquisa Veterinária Brasileira 21(4):143-145. Depto Medicina Veterinária Preventiva, Universidade Estadual de Londrina, Cx. Postal 6001, Londrina, PR 86051-970, Brazil. In this study 713 cows were examined. The animals were from three dairy farms in northern Paraná and the southwest of the State of São Paulo. From these cows, 137 had mastitis. On the three farms, 8 cows (1-12%) with Mycoplasma bovis mastitis were detected. Four were treated with tylosin and oxytetracyçlin and three with enrofloxacin There was no response to the treatments, and these animals were culled during the lactation period. One cow treated with enrofloxacin almost totally recovered milk production, but elimination of M. bovis continued during the lactation, and there was no bacteriological cure. This cow had a normal milk production in the next lactation period, without elimination of M. bovis. Culling of positive animals, the bacteriological study anel correct application of preventive practices for contagious mastitis controlled the dissemination of M. bovis to other animals.

• Mastitis dairy cattle Mycoplasma bovis Mastite gado leiteiro.

Abstract in Portuguese:

RESUMO.- Pretto L.G., Müller E.E., Freitas J.C., Mettifogo E., Buzinhani M., Yamaguti M. & Salvador R. 2001. [Mastitis caused by Mycoplasma bovis in dairy cattle] Mastite bovina por Mycoplasma bovis em rebanhos leiteiros. Pesquisa Veterinária Brasileira 21(4):143-145. Depto Medicina Veterinária Preventiva, Universidade Estadual de Londrina, Cx. Postal 6001, Londrina, PR 86051-970, Brazil. Foram examinadas 713 vacas de três rebanhos leiteiros localizados na região norte do Estado do Paraná e sudoeste do Estado de São Paulo, das quais 137 apresentaram mastite. Nas três propriedades foram detectados oito animais (1, 12%) com mastite clínica por Mycoplasma bovis. Destes animais, quatro tratados com oxitetraciclina e tilosina e três com enrofloxacina, não responderam ao tratamento e foram descartados no decorrer da lactação. Uma vaca medicada com enrofloxacina recuperou quase que totalmente a secreção láctea mas a eliminação de M. bovis persistiu por toda lactação. Esta vaca apresentou cura bacteriológica na lactação seguinte. O descarte dos animais positivos, monitoramento bacteriológico e a aplicação correta das me9idas de prevenção para as mastites contagiosas controlaram a disseminação de M. bovis nos rebanhos.

Abstract in English:

ABSTRACT.- Irigoyen L.F., Van Alstine W, Turek j. & Clark L.K. 1998. Ultrastructural observation of the airways of recovered and susceptible pigs after inoculation with Mycoplasma hyopneumoniae. [Observação ultra-estrutural das vias aéreas de suínos recuperados e suscetíveis após inoculação com Mycoplasma hyopneumoniae.] Pesquisa Veterinária Brasileira 18(1):1-7. Depto Patologia, Universidade Federal de Santa Maria, Campus Camobi, Santa Maria, RS 97119-900, Brazil. To determine the morphological differences in the epithelium of the airways of recovered and susceptible pigs after Mycoplasma hyopneumoniae challenge, twenty-four 4-week-old M. hyopneumoniae-free pigs were intratracheally inoculated with 107ccu/ml of a pure low-passaged culture of the P5722-3 strain of M. hyopneumoniae challenge material. Eight pigs (group I) were challenged at the beginning of the experiment and rechallenged 3 months late 1: Group II pigs were also challenged at the beginning of the experiment and necropsied 3 months later: Group III pigs were challenged at the sarne time as the rechallenge of group I pigs. Eight nonchallenged pigs served as contrais (group IV). Three days after the second challenge of group I and the first challenge of group III, and every 3 and 4 days thereafter, two pigs from each group were euthanatized by electrocution and necropsied. Samples of bronchi and lung tissue were examined using light and electron microscopy (SEM and TEM). Macroscopic lesions were observed in the lungs of all group III pigs (average = 4.74%) and were characterized by purple-red areas of discoloration and increased firmness affecting the cranioventral aspect of the lungs. Macroscopic lesions of pneumonia in groups I and II were minimal (less than 1%). There were no gross lesions of pneumonia in contrai (group IV) pigs. Microscopic lesions were characterized by hyperplasia of the peribronchial lymphoid tissue and mild neutrophilic infiltrates in alveoli. Electron microscopy showed patchy areas with loss of cilia and presence of leukocytes and mycoplasmas in bronchi of susceptible pigs (group III). The bronchial epithelium of rechallenged (group I), recovered (group II), and control (group IV) pigs was ultrastructurally similar indicating recovery of the former two groups. Although mycoplasmas were seen among cilia, a second challenge on pigs of group I did not produce another episode of the disease nor did it enhance morphological changes, suggesting that those pigs could become carriers of M. hyopneumoniae.

• Mycoplasma hyopneumoniae enzootic pneumonia swine pneumonia enzoótica suíno.

Abstract in Portuguese:

RESUMO.- Irigoyen L.F., Van Alstine W, Turek j. & Clark L.K. 1998. Ultrastructural observation of the airways of recovered and susceptible pigs after inoculation with Mycoplasma hyopneumoniae. [Observação ultra-estrutural das vias aéreas de suínos recuperados e suscetíveis após inoculação com Mycoplasma hyopneumoniae.] Pesquisa Veterinária Brasileira 18(1):1-7. Depto Patologia, Universidade Federal de Santa Maria, Campus Camobi, Santa Maria, RS 97119-900, Brazil. Para determinar as diferenças morfológicas no epitélio das vias aéreas de suínos suscetíveis e recuperados da infecção por Mycoplasma hyopneumoniae, 24 leitões com 4 semanas de idade, livres de infecção por M. hyopneumoniae, foram inoculados intratraquealmente com material contendo 107ccu/ml de cultura pura da cepa P5722- 3 de M. hyopneumoniae. Oito leitões (grupo I) foram inoculados no início do experimento e reinoculados 3 meses mais tarde, após apresentarem a doença e terem se recuperado. Os oito leitões do grupo II foram também inoculados no início do experimento e necropsiados 3 meses depois. Os leitões do grupo III foram inoculados ao mesmo tempo da reinoculação dos leitões do grupo I. Oito leitões não inoculados serviram como controles (grupo IV). Três dias após a reinoculação dos leitões do grupo I e a inoculação do grupo III e, a partir disso, a cada 2 dias, dois leitões de cada grupo foram sacrificados e necropsiados. Segmentos de brônquios e pulmão foram examinados em microscopia ótica e microscopia eletrônica de transmissão e de varredura. Lesões macroscópicas foram observadas nos pulmões de todos os leitões do grupo III (média: 4.74% da superfície) e eram caracterizadas por áreas firmes e avermelhadas nas porções cranioventrais. Lesões macroscópicas semelhantes foram mínimas em pulmões de leitões dos grupos I e II (menos de 1%) e ausentes.no grupo IV. As lesões microscópicas consistiam de hiperplasia do tecido linfóide peribronquial e infiltrado neutrofilico leve nos alvéolos. Na microscopia eletrônica havia lesões focais no epitélio ciliado, caracterizadas por perda de cílios e descamação de células, e presença de leucócitos e micoplasmas nos brônquios de leitões suscetíveis (grupo III). O epitélio bronquial de leitões reinoculados (grupo I), recuperados (grupo II) e controles (grupo IV) era ultraestruturalmente similar, indicando recuperação nos primeiros dois grupos. Embora micoplasmas tenham sido observados entre cilios, uma segunda inoculação em leitões do grupo I não causou outro episódio da doença nem aumentou as alterações morfológicas nos brônquios, sugerindo que esses leitões podem se tornar portadores de micoplasmas.

Abstract in English:

Subcutimeous inoculation of 30-day old SPF chickens with a·commercial oilaemulsfon Mycoplasma gallisepticum bacterin (MG-Bac, lot 23009, Salsbury Lab., Inc., Charles City,·Iowa 50616, USA) protected them against chronic respiratory disease. The·birds were challenged 30 days after vaccination with the R strain of M. gallisepticum injected into the left thoracic air·sac. The vaccinated birds presented, before and after the challenge, geometric mean titers higher than the nonvaccinated ones. Air sacculitis lesions bccurred with lower frequency and intensity among the vaccinated birds than among the nonvaccinated, showing a positive relationship between the protection and the serological response.

• Mycoplasma gallisepticum chronic respiratory disease chicken vaccination oil-emultion bacterin

Abstract in Portuguese:

A inoculação subcutânea de galinhas "SPF" de 30 dias de idade com uma vacina oleosa comercial de Mycoplasma gallisepticum (MG-Bac, partida 23009, Salsbury Lab., Inc., Charles City, Iowa 50616, EUA) protegeu-as contra a doença respiratória crônica. As aves foram desafiadas 30 dias após a vacinação pela injeção no saco aéreo torácico esquerdo com a amostra R de M gallisepticum. As aves vacinadas apresentaram, antes e após o desafio, médias geométricas dos títulos de inibição da hemaglutinação maiores do que as aves não vacinadas. As lesões de aerossaculite ocorreram com frequência e intensidade menores entre as aves vacinadas, relacionando-se positivamente proteção obtida com a resposta sorológica observada.

• Mycoplasma gallisepticum doença respiratória crônica galinhas-vacinação bacterina oleosa