Prevalência e fatores de risco de leptospirose bovina no Estado do Maranhão

Silva F.J., Conceicao W. L. F., Fagliari J.J., Girio R.J.S., Dias R. A., Borba M. R. & Mathias L. A. 2012. [Prevalence and risk factors of bovine leptospirosis in the State of Maranhao, Brazil.] Prevalencia e fatores de risco de leptospirose bovina no Estado do Maranhao. Pesquisa Veterineria Brasileira 32(4): 303-312. Departamento de Medicina Veterinaria Preventiva e Reproducao Animal, Faculdade de Ciencias Agrarias e Veterinarias, Universidade Estadual Paulista, Via de Acesso Professor Paulo Donato Castellane s/n, Zona Rural, Jaboticabal, SP 14884-900, Brazil. E-mail: fjsepi@gmail.com Prevalence and risk factors of bovine leptospirosis in the State of Maranhao were investigated. Based on production parameters that vary across different production systems, management practices, the purpose of exploitation, the average size of herds and market systems, the state was divided in four sampling circuits. The study aimed to investigate the epidemiological features of bovine leptospirosis in the State of Maranhao, in order to determine the prevalence of the infection in cattle and herds, to determine the occurrence of serovars of Leptospira spp., to identify risk factors associated with leptospirosis in cattle and to differentiate the livestock circuits itself regarding the prevalence of leptospirosis. The survey was conducted in 136 herds in the circuit I, in which 841 >= 24 months old females were analyzed; 238 in the circuit II and 2,582 females were analyzed; 122 in the circuit III and 869 females were analyzed; 77 in the circuit IV and 540 females were analyzed; a total of 573 herds and 4,832 females were analyzed. The presence of antibodies against Leptospira spp. was verified by microscopic agglutination test (MAT). Of the 4,832 cows examined, 1,904 (35.94%, CI 95% = 33.01% -38.98%) were positive. Of the 573 herds, 380 (64.81%, CI 95% = 61.10% -68.35%) were positive. Serovars Hardjo and Wolffi were the most frequent in the state. The circuit III showed the lowest prevalence of leptospirosis in all comparisons. The variables presence of horses (p = 0.000), presence of capybaras (p = 0.034) and herds with up to 32 adult females (p = 0.002) were identified as risk factors for leptospirosis.

Cytology of tracheobronchial and bronchoalveolar lavage in healthy Holteins calves during the first month of life

Benesi F.J., Wachholz L., Bertagnon H.G., Leal M.L.R., Mori E. & Fernandes W.R. 2012. [Cytology of tracheobronchial and bronchoalveolar lavage in healthy Holteins calves during the first month of life.] Citologia dos lavados traqueobronquico (LTB) e broncoalveolar (LBA) de bezerros holandeses sadios durante o primeiro mes de vida. Pesquisa Veterinaria Brasileira 32(3):267-270. Departamento de Clinica Medica, Faculdade de Medicina Veterinaria e Zootecnia, Universidade de Sao Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Sao Paulo, SP 05508-270, Brazil. E-mail: febencli@usp.br The neonatal calf is a critical moment for adaptation of the newborn to extra uterine life. The respiratory tract is functionally very demanded and often affected by disease, resulting in direct loss of their function and causing serious economic losses in livestock. The basic point to reduce these losses is appropriate clinical evaluation of neonates; but the diagnosis based solely in physical examination is very difficult to establish. The use of complementary analysis such cytology of the respiratory tract becomes an important diagnostic tool; however their findings must be standardized in the face of different techniques employed. This research studied the dynamics of the cellularity of the bronchoalveolar and tracheobronchial region obtained through lung lavage harvested by nasotracheal catheterization technique and tracheocenthesis respectively, during the first month of life of healthy calves. The tracheobronchial cytology was influenced by the time, showing decreased number of alveolar macrophages and greater number of neutrophils, possibly increased by local irritation caused by the technique, which was repeated sequentially, and/or through greater stimulation of inhaled microorganisms deposited in this region. In the bronchoalveolar region no variation in the cellular constituents in function of time was found. The results allowed the conclusion the cell population of the tracheobronchial region has changed over the week-old calves, possibly due to the technique used and/or to the normal region physiology, represented by higher magnitudes of neutrophils. Otherwise, the cells of the broncholaveolar region showed a stable behavior during the first month of life of newborn calves, presenting numerical predominance of alveolar macrophages. O período neonatal dos bezerros é um momento crítico para adaptação do recém-nascido à vida extra uterina e o sistema respiratório, um dos mais exigidos funcionalmente, é frequentemente afetado por enfermidades, redundando no prejuízo direto da sua função e acarretando perdas econômicas importantes na pecuária. O ponto básico para reduzir estas perdas, é representado pela adequada avaliação clínica dos neonatos, todavia o diagnóstico baseado exclusivamente no exame ísico é muito di ícil de ser estabelecido. O uso de exames complementares como a citologia do trato respiratório torna-se uma ferramenta diagnóstica importante nestes casos, porém faz-se necessário, padronizar seus achados frente às diferentes técnicas empregadas para a sua obtenção. Assim, o presente estudo propôs-se acompanhar as variações dos constituintes celulares da região traqueobrônquica e broncoalveolar obtidos por lavados respiratórios pelos métodos de traqueocentese e por colheita nasotraqueal respectivamente, durante o primeiro mês de vida de bezerros sadios. Observou-se alteração no quadro citológico ao longo do tempo, quando a região traqueobrônquica foi lavada, expresso por diminuição da porcentagem de macrófagos alveolares, com aumento de neutró ilos, possivelmente, por maior irritação local provocada pela técnica, que se repetiu sequencialmente e/ou por maior estimulo de microorganismos inalados depositados nesta região. Na região broncoalveolar, não encontraram- -se variações nos constituintes celulares em função do tempo. Os resultados permitiram a conclusão que a população celular da região traqueobrônquica modi icou-se ao longo das semanas de vida dos bezerros, possivelmente pela técnica empregada e/ou isiologia normal da região, sendo representadas por maiores magnitudes de neutró ilos. De modo diverso, na região broncolaveolar, as células evidenciaram um comportamento estável durante o primeiro mês de vida dos bezerros neonatos, apresentando predomínio numérico dos macrófagos alveolares.

Characterization of yolk sac proteins of Bos indicus cattle embryos

The yolk sac is an embryonic membrane that is essential for the embryo's initial survival in many mammals. It also plays an important role in the production of proteins necessary for development. We studied proteins of the yolk sac in bovine embryos at up to 40 days of gestation. We examined the yolk sac of 17 bovine embryos at different gestational periods, measuring a-fetoprotein, alpha-1-antitrypsin, and transferrin. This experiment was carried out by Western blot technique, associated with electrophoresis on a 6% sodium dodecyl sulfate polyacrylamide gel. Mouse monoclonal antibody anti-human-alpha-fetoprotein, mouse antibody anti-human-transferrin and rabbit polyclonal anti-human-alpha-1-antitrypsin were used as primary antibodies, and conjugated peroxidase as a secondary antibody. We detected the three proteins in some of the yolk sac samples; however, the bands in some specimens (samples) were weak, maybe a result of poor antigen-antibody reaction, since the antibodies used in this study were not specific to bovine proteins. The fact that weak bands appeared might be due to a weak cross-reaction.

Prevalence of leptospirosis in dairy goats in the semiarid region of Paraiba state

Higino S.S.S., Alves C.J., Santos C.S.A.B., Vasconcellos S.A., Silva M.L.C.R., Brasil A.W.L., Pimenta C.L.R.M. & Azevedo S.S. 2012. [Prevalence of leptospirosis in dairy goats in the semiarid region of Paraiba state.] Prevalencia de leptospirose em caprinos leiteiros do semiarido paraibano. Pesquisa Veterinaria Brasileira 32(3):199-203. Universidade Federal de Campina Grande, Centro de Saude e Tecnologia Rural, Unidade Academica de Medicina Veterinaria, Av. Universitaria s/n, Patos, PB 58700-970, Brazil. E-mail: sergio.azevedo@pq.cnpq.br This study aimed to determine the prevalence of positive dairy goat herds and seropositive animals for leptospirosis in the semiarid region of Paraiba state, Brazil. Sampling was designed to determine the prevalence of positive herds (foci) and seropositive animals for leptospirosis. A total of 975 serum samples were collected from goats of 110 dairy herds in the Monteiro municipality, Western Cariri microregion of Paraiba. For the serological diagnosis of leptospirosis the microscopic agglutination test (MAT) was carried out using 24 Leptospira spp. serovars as antigens. A herd was considered positive when existed at least one seropositive animal. The prevalence of positive herds and seropositive animals were 43.6% (95% CI = 34.2-53.4%) and 8.7% (95% CI = 58.7-12.9%) respectively. The most frequent serovars in goats were Autumnalis (1.74%; 95% CI = 0.97-3.09%), Sentot (1.71%; 95% CI = 0.82-3.52%) and Whitcomb (1.39%; 95% CI = 0.65-2.93%), and by herd, serovars Autumnalis (10.9%; 95% CI = 5.8-18.3%), Whitcomb (8.2%; 95% CI = 3.8-15.0%) and Sentot and Patoc (7.3%; 95% CI = 3.2-13.8%) were the most frequent. It is suggested that leptospirosis is spread in goats in the region, and that there is need to implement control and preventive measures in order to reduce infection and economic losses, and to avoid possible transmission of infection to humans.

Effect of nAellore cows ciclicity on conception and pregnant rates after synchronization protocols for fixed timed artificial insemination

Palhano H.B., Jesus V.L.T., Abidu-Figueiredo M., Baldrighi J.M. & Mello M.R.B. [Effect of nAellore cows ciclicity on conception and pregnant rates after synchronization protocols for fixed timed artificial insemination]. Efeito da ciclicidade de vacas Nelore sobre as taxas de concepcao e de prenhez apos protocolos de sincronizacao para inseminacao artificial em tempo fixo. Revista Brasileira de Medicina Veterinaria, 34(1):63-68, 2012. Departamento de Biologia Animal, Universidade Federal Rural do Rio de Janeiro, BR 465 km 7, Seropedica, RJ 23890-000, Brasil. Email: hbpalhano@gmail.com The present study evaluated the effect on conception and pregnancy rates of Nellore cows selected for Fixed Timed Artificial Insemination (FTAI) program, submitted to four synchronization protocols. Four hundred and ninety lactating females were used and assigned to eight groups: I-OvSynch, n=68, with selection of cycling cows; II-OvSynch + progesterone (P-4), n=67, after selection of non-cycling animals; III-OvSynch, without selection, n=68; IV-OvSynch + P-4, without selection, n=67; V-Co-Synch, n=55, with selection of cycling cows; VI-Co-Synch + P-4, n=55, with selection non-cycling cows; VII- Co-Synch without selection, n=55; VIII- Co-Synch + P-4, without selection, n=55. The conception and pregnancy rates were, respectively, 45.6%, 27.9% and 82.4%, 48.5% for groups I and III; 61.2%, 37.3% and 85.1%, 58.2% for groups II and IV; 43.6%, 25.5% and 80%, 41.8% for groups V and VII; 52.7%, 32.7% and 83.6%, 50.9% for groups VI and VIII. When compared these rates, the results after chi-square test showed significant difference (P < 0.05) among protocols with or without selection. There was no significant difference (P > 0.05) between OvSynch and Co-Synch protocols, with or without P-4 and with selection, considering Co-Synch a viable option for optimization of FTAI. In conclusion, the selection of cows before FTAI program contributed significantly to improve the conception and pregnancy rates.

Avaliação ecocardiográfica do átrio esquerdo de cães sadios por meio do modo-M convencional e do modo bidimensional

Avaliaram-se o átrio esquerdo (AE) utilizando-se o método bidimensional (2-B) (corte transverso) e a relação átrio esquerdo:aorta (AE:Ao), em um grupo de 40 cães adultos e sadios, entre um, cinco e sete anos de idade e com pesos corpóreos de 3,2kg a 38,3kg, e compararam-se esses valores aos do modo-M convencional. Observou-se diferença entre AE e Ao nos dois métodos e entre os seus respectivos índices. A correlação foi positiva alta entre peso e superfície corpórea e entre AE no modo 2-B (AEB) e AE no modo-M (AEM). Não se observou correlação entre os índices, nos dois métodos, com o peso e a superfície corpórea, isto é, os índices são independentes do peso ou da superfície corpórea. Concluiu-se que o AEB é maior do que o AEM, o índice médio para o AEB:AoB é de 1,379, e o intervalo de confiança de 1,337 a 1,422. O índice no método 2-B é, portanto, superior ao índice no modo-M.

Epidemiological characterization and risk factors associated with leptospirosis in the brazilian semiarid

Alves C. J., Alcino J. F., Farias A. E. M., Higino S. S. S., Santos F. A., Azevedo S. S., Costa D. F. & Santos C. S. A. B. 2012. [Epidemiological characterization and risk factors associated with leptospirosis in the brazilian semiarid.] Caracterizacao epidemiologica e fatores de risco associados a leptospirose em ovinos deslanados do semiarido brasileiro. Pesquisa Veterinaria Brasileira 32(6): 523-528. Universidade Federal de Campina Grande, Centro de Sa de e Tecnologia Rural, Unidade Academica de Medicina Veterinaria, Av. Universitaria s/n(o), Patos, PB 58700-970, Brazil. E-mail: clebertja@uol.com.br The aim of this investigation was to determine the herd-level and animal-level prevalence of leptospirosis in sheep from the semiarid of Paraiba State, Northeast Brazil, as well as to identify risk factors. Blood samples were collected from 1,275 sheep from 117 flocks in 19 counties in the Sertao mesoregion, Paraiba. For the serological diagnosis of leptospirosis the microscopic agglutination test (MAT) using 24 Leptospira spp. serovars as antigens was carried out. Of the 117 flocks studied 33 (28.20%) presented at least one seropositive sheep, and of the 1,275 animals 69 (5.41%) were seropositive with titers ranging from 100 to 3,200. Reactant serovars were Autumnalis (49.30%), Andamana (27.53%), Sentot (17.39%), Whitcomb (4.34%) and Australis (1.44%). Herd size > 48 sheep (odds ratio = 2.26; 95% CI = 1.33-5.07; p = 0.021) and participation in animal exhibits (odds ratio = 9.05; 95% CI = 0.96-85.71; p = 0.055) were identified as risk factors. The need was suggested for studies on the isolation of the agent, characterization of its pathogenicity and its economic impact on sheep flocks of the region, and sanitary control in sheep agglomerations was recommended.

Polymorphonuclear leukocytes CH138+apoptosis evaluation in milk with high and low somatic cell count - preliminary data

Polymorphonuclear leukocyte (PMNL) apoptosis is central to the successful resolution of inflammation. Since Somatic Cell Count (SCC) is an indicator of the mammary gland's immune status, this study sought to clarify the influence that these factors have on each other and on the evolution of the inflammatory process. Milk samples were stained with annexin-V, propidium iodide (PI), primary antibody anti-CH138A. Negative correlation between SCC and PMNL apoptosis was found, and a statistical difference between high SCC group and low SCC group was observed concerning the rate of viable PMNL, apoptotic PMNL, necrotic PMNL and necrotic and/or apoptotic PMNL. Overall, the high cellularity group presented lower proportions of CH138+ cells undergoing apoptosis and higher proportions of viable and necrotic CH138+ cells. Thus, it can be concluded that PMNL apoptosis and SCC are related factors, and that in high SCC, milk apoptosis is delayed. Although there is a greater amount of active phagocytes in this situation, apoptosis' anti-inflammatory effects are decreased, while necrosis' pro-inflammatory effects are increased, which can contribute to chronic inflammation.

Jatropha curcas pericarp toxicity in sheep

Physic nut (Jatropha curcas) is a plant cultivated for biofuel production. Pericarp is a potential livestock food source by-product. However, its use may be limited due to the presence of toxic compounds, mainly phorbol esters. Thus, this study aimed to evaluate pericarp toxicity. Twenty sheep were divided in four groups, one control group which did not receive the plant and three experimental groups which received pericarp in 15% (G15), 30% (G30) and 45% (G45) concentrations for 23 days. After 10 days of treatment, pericarp ingestion produced food intake decrease, diarrhea, dehydration and loss of body condition. All treated groups showed decrease in alkaline phosphatase activity. G30 animals presented reductions in urea and total protein concentrations, and increase in potassium and sodium levels. G45 animals showed increase in serum aspartate aminotransferase activity and in albumin, creatinin, total and indirect bilirubin levels. Anatomohistopathologic findings included ascites, hydropericardium, congestion of the gastintestinal tract and lungs, pulmonary edema and adhesions in the thoracic cavity, renal tubular cells and centrilobular cytoplasmic vacuolation and lymphohistiocytic pneumonia and lymphoplasmacytic and histiocytic enteritis. On the physiochemical analysis 0.3845mg of phorbol esters/g of pericarp were detected. It is concluded that J. curcas pericarp is toxic and is not recommended for sheep feeding.

Genetic correlations and heritability estimates of reproductive traits of Nellore bulls

Estimates of phenotypic, genetics and residual variances for reproductive traits in 5903 Nellore bulls were obtained. The experimental model used was multiple trait derivative-free restricted maximum likelihood. The values obtained for heritability were 0.24 +/- 0.05 for scrotal circumference at 450 days of age and 0.37 +/- 0.05 at 21 months for age at the time of the breeding soundness evaluation; 0.24 +/- 0.05 and 0.26 +/- 0.05 for left and right testicle length; 0.29 +/- 0.05 and 0.31 +/- 0.05 for left and right testicle width; 0.12 +/- 0.04 for testicle format; 0.33 +/- 0.06 for testicle volume; 0.11 +/- 0.03 for gross motility; 0.08 +/- 0.03 for individual motility and 0.05 +/- 0.02 for spermatic vigor; 0.20 +/- 0.04, 0.03 +/- 0.02 and 0.19 +/- 0.04 for larger defects, smaller defects and total defects, respectively. The values for heritability for testicular biometric characteristics were moderate to high while the seminal characteristics, presented low values. Genetic correlations between scrotal circumference with all the reproductive traits were favorable, suggesting the scrotal circumference as a feature of choice in the selection of bulls.

Macroscopic description of teeth of Azara's agouti (Dasyprocta azarae)

Oliveira F.S., Martins L.L., Canola J.C., Oliveira P.T., Pecora J.D. & Pauloni A.P. 2012. Macroscopic description of teeth of Azara's agouti (Dasyprocta azarae). Pesquisa Veterinaria Brasileira 32(1):93-95. Departamento de Medicina Veterinaria, Universidade Estadual de Maringa, Campus Umuarama, Cx. Postal 65, Umuarama, PR 87501-970, Brazil. E-mail: singaretti@ig.com.br The teeth of Azara's agouti (Dasyprocta azarae) were described macroscopically in order to provide biological data on one of the largest wild rodents of the Americas. Radiography was taken on six heads and the teeth were described. Enamel surrounds the coronal dentin, projects to the roots and is present as parallel inner laminae in buccolingual direction. The dentin is located among the enamel laminae and surrounds the pulp horns. The cementum is located internally to the enamel laminae. On the lingual surface, the cementum and dentin are the outer elements.

Genotyping of polymorphisms in the prnp gene in Santa Ines sheep in the State of Sao Paulo, Brazil

Santos C.R., Mori E., Leao D.A. & Maiorka P.C. 2012. [Genotyping of polymorphisms in the prnp gene in Santa Ines sheep in the State of Sao Paulo, Brazil.] Genotipagem de polimorfismos no gene prnp em ovinos Santa Ines no Estado de Sao Paulo. Pesquisa Veterinaria Brasileira 32(3):221-226. Laboratorio de Neuropatologia Experimental e Comparada, Departamento de Patologia, Faculdade de Medicina Veterinaria e Zootecnia, Universidade de Sao Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitaria, Sao Paulo, SP 05508-270, Brazil. E-mail: caio-patologia@usp.br Enzootic paraplexia or scrapie is a fatal neurodegenerative disease affecting mainly sheep and rarely goats. The disease is influenced by polymorphisms at codons 136, 154 and 171 of prnp gene that encodes the prion protein. The animals may be susceptible or resistant to the development of the disease according to the allelic sequences observed in these codons. In Brazil there were only cases of scrapie in imported animals, therefore the country is considered free of the disease. This study performed the genotyping of different polymorphisms associated to the development of scrapie. Then, based on these findings the animals were categorized in resistant and susceptible. A total of 118 samples were sequenced from the Santa Ines sheep raised on properties located in the State of Sao Paulo. From these samples, 6 alleles and 11 genotypes were identified (ARQ / ARQ, ARR / ARQ, ARQ / AHQ, ARQ / VRQ, AHQ / AHQ, ARR / ARR, ARR / AHQ, VRQ / VRQ, ARQ / TRQ, TRR / TRR, TRQ / TRQ), the genotype ARQ / ARQ presented a frequency of 56.7%. It was also detected the presence of tyrosine at codon 136, which may be considered a rare observation, since there is no report regarding Santa Ines breeding presenting this polymorphism. These results showed the great genetic variability in Santa Ines in Sao Paulo and only 1,69% of the genotypes observed are extremely resistant to scrapie. These data demonstrate that the Santa Ines sheep can be considered potentially susceptible to scrapie.

Quality and quantity of milk produced by Saanen goats submitted to stress during three sequential days

The experiment aimed to study the effect of physiological stress on cortisol levels, quality and quantity of milk through punctual administration of ACTH. Twelve Saanen goats were divided in two experimental groups: ACTH group (0,5 mu g of ACTH/Kg.L.W); Placebo group (placebo solution). Milk production, and percentages of protein, fat, lactose and SCC (somatic cells counting) of the milk were analyzed before, during and after the administration of ACTH/placebo. Simultaneously to the ACTH/placebo administration and during three sequential days, blood was collected to evaluate cortisol concentrations. At times -30 and zero, both groups presented basal concentrations of cortisol. The increase of cortisol contents was significant at times 60 (group ACTH: 59.00 +/- 5.70 and groups placebo: 5.23 +/- 1.37ng/mL) and 120 (group ACTH: 47.96 +/- 9.72 and group placebo: 4.38 +/- 1,14ng/mL) since the cortisol content was higher on the ACTH group. The values returned to the basal level at 300 minutes. Concerning milk production, no differences were found between ACTH and placebo groups. Milk, protein, fat, lactose and SCC did not distinguish one group from another. The results indicated that the physiological stress induced during three days was not harmful to milk production and milk quality of Saanen goats.

Erytrogram of healthy female Holstein calves during the first month of life

Benesi F.J., Teixeira C. M. C., Lisboa J.A.N., Leal M. L. R., Birgel Jr E. H., Bohland E. & Mirandola R. M. S. 2012. [Erytrogram of healthy female Holstein calves during the first month of life.] Eritrograma de bezerras sadias, da raca Holandesa, no primeiro mes de vida. Pesquisa Veterinaria Brasileira 32(4): 357-360. Departamento de Cl nica Medica, Faculdade de Medicina Veterinaria e Zootecnia, Universidade de Sao Paulo, Campus Universitario, Av. Prof. Dr. Orlando Marques de Paiva 87, Sao Paulo, SP 05508-000, Brazil. E-mail: febencli@usp.br In order to establish reference values, and to assess the in fluence of the age factor on the erytrogram of healthy Holstein calves, blood samples from 300 animals were used, spread over 15 experimental groups, according to age, in the first month of life. Variations of the average values for the components of erytrogram were as follows: number of red blood cells (x10(6)/mm(3)) = 6.68-7.60, packed cell volume (%) = 29.80-33.35, hemoglobin concentration (g/dl) = 9.00-10.43, mean corpuscular volume (fl) = 38.93-47.68, mean corpuscular hemoglobin (pg) = 11.75-14.69, mean corpuscular hemoglobin concentration (%) = 29.53-31.63% and number of reticulocytes (x10(3)/mm(3)) = 0.00-11.86. The in fluence of the age factor proved to be significant for the mean corpuscular volume, mean corpuscular hemoglobin and the number of reticulocytes.

Use of Leptospira spp. strains isolated in Brazil in the microscopic agglutination test applied to diagnosis of leptospirosis in cattle herds in eight brazilian states

Sarmento A.M.C., Azevedo S.S., Morais Z.M., Souza G.O., Oliveira F.C.S., Goncales A.P., Miraglia F. & Vasconcellos S.A. 2012. [Use of Leptospira spp. strains isolated in Brazil in the microscopic agglutination test applied to diagnosis of leptospirosis in cattle herds in eight brazilian states.] Emprego de estirpes Leptospira spp. isoladas no Brasil na microtecnica de soroaglutinacao microscopica aplicada ao diagnostico da leptospirose em rebanhos bovinos de oito estados brasileiros. Pesquisa Veterinaria Brasileira 32(7);601-606. Universidade de Sao Paulo, Faculdade de Medicina Veterinaria e Zootecnia, Departamento de Medicina Veterinaria Preventiva e Saude Animal, Av. Prof. Dr. Orlando Marques de Paiva 87, Sao Paulo, SP 05508-270, Brazil. E-mail: savasco@usp.br The aim of this study was to investigate the adequacy of the use of autochthonous strains of leptospires isolated in Brazil, added to antigen collection of the microscopic agglutination test (MAT) applied to the diagnosis of bovine leptospirosis. By means of non-probability sampling, 109 farms and 9,820 cattle, females at reproductive age were chosen from 85 municipalities in the states of Goias, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Parana, Rio Grande do Sul, Santa Catarina and Sao Paulo. Among the 9,820 examined animals, 5,806 (59.12%) were reactants at MAT for at least one serovar using the 23 reference serovars. Employing the collection of reference serovars and the ten autochthonous strains, 6,400 (65.24%) reactants and significant difference (p=0.001) was found. The most probable serovars identified by the collection of reference antigens were Hardjo (43.03%), Shermani (20%), Wolfi (9.96%), Grippothyphosa (5.42%) and Pomona (4.28%). With the collection amplified with the ten strains isolated in Brazil, the most probable serovars were Hardjo (31%), Guaricura-M4/84 (22.50%), Shermani (15.43%), Wolffi (4.76%), Grippothyphosa (3.71%) and Autumnalis (3.24%). The serovar Guaricura, strain M4/84, isolated from bovines and buffaloes in the State of Sao Paulo, was ranked as one of the three most probable serovars in the states of Goias, Mato Grosso, Mato Grosso do Sul, Minas Gerais and Sao Paulo. The addition of autochthonous strains to the MAT antigen collection provided the confirmation of the diagnosis of leptospirosis in 594 cattle (6%) which have been classified as non-reactants by the reference collection (p=0.001).