Maria Lúcia Barreto

Contagious agalactia by Mycoplasma agalactiae in small ruminants in Brazil: first report

Two outbreaks of contagious agalactia by Mycoplasma agalactiae occurred in Paraiba State, Northeastern Region of Brazil are reported. The disease was characterized by mastitis, agalactia and polyarthritis in does and polyarthritis and conjunctivitis in kids and lambs. Fever and anorexia were also observed. Morbidy was from 26.1% to 100% in does, 36.5 to 100% in kids and 49% in lambs. In one farm 14.3% of the lactating goats and 6.4% of the kids died or were euthanized. In the other, 3.3% of the does, 36.5% of the kids and 22.9% of the lambs died and 84 affected goats were euthanized to control the disease. M. agalactiae was isolated from milk, joint exudates, nasal swabs and ear washings. The colonies were characteristic of Mycoplasma and the agent did not ferment both glucose and arginin. It was typed as Mycoplasma agalactiae by immunoperoxidase and PCR. This is the first report of M. agalactiae infection in Brazil, but the source of the infection remains unknown.

Potentially pathogenic mycoplasmas in the external ear canal of clinically normal cattle in Southeast Brazil: first report

Mycoplasmas were searched in the ear canal flushing of 60 bovine in Brazil. The prevalence obtained was 80%. The percentages of typified species were 12.5%, for M. alkalenses; 2.1%, M. arginini; 8.35%, M. bovirhinis; 2.1%, M. bovis; 25.0%, M. conjunctivae; 14.6%, M. mycoides subsp. mycoides LC and 10.4% M. capricolum.

Serologic response of SPF chickens to live vaccines and other strains of Mycoplasma gallisepticum

False positive serologic reactions and difficulties in the diagnosis of Mycoplasma gallisepticum (MG) in chickens have increased lately as a result of infection by low virulent MG strains and the use of live MG vaccines in poultry. The objective of this study was to evaluate the serologic responses of SPF chickens exposed to the three commercially available live MG vaccines, and one low virulent MG strain (MG-70), contributing to the diagnosis and monitoring of MG infection in birds. Six groups of SPF chickens were used. The control group was not infected nor challenged; one group was infected with the low virulent strain MG-70 (MG-70); three groups were immunized and named after the MG vaccine used, i.e., MG-6/85, MG-ts11, and MG-F; and finally one group was infected with the virulent MG standard strain, MGR. Random Amplification of Polymorphic DNA (RAPDPCR) was used to compare the strains to each other, to the standard MG-A5969, and to MGR. All strains were found to be genetically distinguishable from each other. Birds in the control group showed negative results throughout the experiment and showed no cross-reaction with M. synoviae in any serologic test. ELISA tests at 21 days post first exposure (P1E) and seven days after the second exposure (P2E), evidenced that 25% of the MG70 birds were positive, whereas vaccine groups yielded higher positivity rate, i.e., 57%, 43% and 29% for MG-6/85, MG-ts11 and MG-F, respectively. Serum plate agglutination (SPA) evidenced the first positive results at 35 days P1E on birds in the MG-F group at the rate of 100%; followed by 40% of birds in the MG-70 group at 63 days P1E. Chickens in MG-ts11 and MG 6/85 groups had identical behavior and yielded 100% positive SPA at 77 days P1E. In regard to hemagglutination inhibition (HI), 14 % of the birds in MG-F and MG-ts11 reacted at 42 days P1E, while MG-70 and MG-6/85 groups yielded positive results only after challenge; MG-70 birds reacted at 56 days P1E at the rate of 17% against 63 days P1E for 100% of MG-6/85 birds. The time lag for positive serologic response was monitored on a weekly basis and was statistically different among groups (p<0.05) by Analysis of Variance (ANOVA). No clinical signs or gross lesions were seen in the control, vaccinated or MG-70 infected birds. Tracheitis and airsaculitis were observed in birds in the MG-R group. MG was isolated from all studied groups.

Detection of Mycoplasma pulmonis in laboratory rats

This work was conducted on rats in two premises located in Niteroi and Rio de Janeiro, Brazil. One is classified as conventional controlled and the other, conventional. The objective of the present study was to detect the presence of Mycoplasma pulmonis in animals with symptoms of respiratory disease and low reproductive performance. In the conventional controlled premises, 16 rats of Wistar-Furth strain were necropsied while in the conventional premises necropsy was performed on 12 rats of Hooded Lister strain. The clinical samples of lungs, trachea, oropharynx, middle ear, uterus and ovaries were subjected to culturing while the sera were tested for antibody detection. From 28 rats, 57.14% (16/28) were culture positive for M. pulmonis, being 81.25% (13/16) from the conventional controlled premises, and 25.00% (3/12) from the conventional premises. The ELISA test was carried out in 20 animals of both colonies. In the conventional controlled premises, 92.86% (13/14) were positive for M. pulmonis, and 7.14% (1/14) were suspicious, while in the conventional premises, 100% (6/6) of the samples were positive. The results confirmed that M. pulmonis was the etiologic agent of the disease that affected the rats under study, and that the ELISA positivity rated higher than culture.

Associação entre Mycoplasma spp. e ácaros do conduto auditivo de bovinos

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 cattles 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 synoviae infection on Newcastle disease vaccination of chickens

A doenca de Newcastle e caracterizada por manifestacoes respiratorias associadas a sintomas nervosos e/ou digestivos. Sua prevencao e feita pela vacinacao com vacinas vivas atenuadas (cepas lentogenicas) e/ou inativadas. As cepas lentogenicas podem determinar acentuada reacao pos-vacinal, principalmente na presenca de outros patogenos. Entre eles, o Mycoplasma synoviae tem importância mundial, principalmente no Brasil. A disseminacao deste agente nos planteis avicolas tem sido facilitada, devido a dificuldades de reproducao e diagnostico da doenca em aves, variacao de virulencia entre as diferentes cepas de M.synoviae e atribuicao a outros patogenos de manifestacao tipica da micoplasmose por M.synoviae. Este estudo experimental em aves (Gallus gallus) SPF, previamente infectadas por M.synoviae e depois vacinadas contra Newcastle, foi realizado com objetivo de avaliar a patogenicidade do M.synoviae pela obtencao dareacao respiratoria pos-vacinal e a resposta sorologica para o virus vacinal da doenca de Newcastle, na ausencia de fatores ambientais. Um total de 86 aves, com tres dias de idade foram utilizadas, sendo 57 infectadas via ocular e intranasal, com cepa MS WVU 1853, ativada em galinhas. Sete dias depois, 21 aves infectadas por micoplasma e 29 nao infectadas foram vacinadas contra a doenca de Newcastle. Como resultados, aves nao infectadas e vacinadas produziram resposta sorologica para o virus vacinal da doenca de Newcastle, significativamente mais elevada e mais duradora que aquelas infectadas e vacinadas. Igualmente, aves infectadas e vacinadas produziram reacoes sorologicas para M.synoviae mais baixa, que aquelas apenas infectadas. Nao foram observadas reacoes respiratorias pos-vacinal nas aves vacinadas.

Mixed antigen ELISA of Mycoplasma pulmonis and M. arthritidis for diagnosis of murine mycoplasmosis

Mariana Thomaz de Oliveira e Silva1*, Maria Lúcia Barreto2, Jenif Braga de Souza3,4, Elmiro Rosendo do Nascimento5, Maurício Afonso Verícimo6 & Veronica Figueiredo do Amaral6 1Biologist, MSc. Núcleo de Animais de Laboratório, Pró-Reitoria de Pesquisa, Pós-graduação e Inovação – Proppi, Universidade Federal Fluminense – UFF, Niterói, RJ, Brasil 2Veterinary, PhD. Núcleo de Animais de Laboratório, Pró-Reitoria de Pesquisa, Pós-graduação e Inovação – Proppi, Universidade Federal Fluminense – UFF, Niterói, RJ, Brasil 3Veterinary, MSc. Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro – UERJ, Rio de Janeiro, RJ, Brasil 4Veterinary, MSc. Instituito de Ciências em Biomodelos, Fundação Oswaldo Cruz – Fiocruz, Rio de Janeiro, RJ, Brasil 5Veterinary, PhD. Faculdade de Medicina Veterinária, Universidade Federal Fluminense – UFF, Niterói, RJ, Brasil 6Veterinary, PhD. Departamento de Imunobiologia – DI, Instituto de Biologia – IB, Universidade Federal Fluminense – UFF, Niterói, RJ, Brasil

PRINCIPAIS ALTERAÇÕES NO LEITE POR AGENTES CAUSADORES DE MASTITE NO REBANHO CAPRINO DOS ESTADOS DE MINAS GERAIS E RIO DE JANEIRO

Goat mastitis causes significant economic losses due to the discarding of milk, costs of drugs and veterinary care, reducing the quantity and quality of milk and dairy products. In this study, 129 raw milk samples from 11 goat farms were investigated by the Tamis test, California mastitis test (CMT), bacteriological exam, presence of Mycoplasma spp. and physicochemical parameters. Seven (4.6%) and four samples (3.1%) were positive by CMT and Tamis test respectively. Bacteriological exam was positive from 57.4% of samples and coagulase-negative Staphylococcus was the most frequent bacteria isolated showing 56% of the strains resistant to penicillin and no resistance to gentamicin. Negative results were obtained from traditional culture as well as by PCR for Mycoplasma spp. The diagnosis of mastitis, the bacteriological exam and the CMT results differed significantly and no association was observed (chi squared, p 0.05). The physicochemical parameters differed significantly (ANOVA, Tukey-Kramer, p < 0.05) among the herds. These results indicate the need to associate microbiological exam when the CMT is used for the diagnosis of goat mastitis.