RESUMEN

INTRODUCTION: Bovine anaplasmosis is caused by the bacterium Anaplasma marginale; its transmission occurs through vectors such as ticks. Crioula Lageana is a native cattle breed from the South of Brazil used for beef production, with excellent meat quality. There are no studies of the epidemiology of this disease in Crioula Lageana even though tick damage is known to be frequent. METHODOLOGY: Blood samples were collected from 311 Crioula Lageana cattle and subjected to DNA extraction and polymerase chain reaction (PCR) using specific primers for the Major Surface Protein 5 (msp5) gene for the detection of the bovine anaplasmosis agent. The animals were classified according to the gender, the category and the presence or absence of ticks at the time of collection. The animal owners completed an epidemiological questionnaire to determine factors that might be associated with anaplasma infection. RESULTS: The prevalence of A. marginale was 79.9%. The following factors were found to be protective against infection: I) the breeding objectives (whether animals were destined for beef production and trade or solely for beef production), II) tick control rate; and III) pregnant and lactating cows and calves as the categories least affected by the hemoparasite. The main risk factor for hemoparasite acquisition was the use of organophosphates and avermectins as acaricides. CONCLUSIONS: Crioula Lageana cattle are in a situation of enzootic stability, with a high prevalence of A. marginale infection. The factors associated with the infection were: I) breeding objectives, II) tick control rate, III) the acaricides used, and IV) the most tick-parasitized categories of cattle.

Asunto(s)

Anaplasma marginale/genética , Anaplasmosis/epidemiología , Enfermedades de los Bovinos/epidemiología , Anaplasma marginale/clasificación , Anaplasma marginale/patogenicidad , Anaplasmosis/sangre , Animales , Brasil/epidemiología , Cruzamiento , Bovinos , Enfermedades de los Bovinos/microbiología , ADN Bacteriano/genética , Femenino , Lactancia , Masculino , Filogenia , Prevalencia , Factores de Riesgo , Garrapatas/microbiología

RESUMEN

The present study aimed to characterize the importance of the Anaplasma marginale, Babesia bovis and Babesia bigemina in the genesis of cattle tick fever (CTF) among dairy calves in the northwest of Minas Gerais, Brazil. Blood samples from 300 calves were collected, followed by DNA extraction and nested PCR using oligonucleotide primers to amplify fragments of the semi-nested for the msp5 gene (A. marginale), sbp-4 (B. bovis) and rap-1a (B. bigemina) Among the examined calves, the prevalence of A. marginale was 55.6% (n=167/300), B. bovis was 4.0% (n=12/300) and B. bigemina was 15.3% (n=46/300), by PCR techniques. Parasitic forms of A. marginale and B. bigemina were found in 36,3% and 2,6% of the blood smears while B. bovis was not detected. There was a statistical difference between the positivity of infected animals in the age groups 1 (10-70 days) and (>70-300 days) for A. marginale and B. bigemina. A total of 15 calves with the classic symptoms of disease were examined, and the samples obtained were confirmed as a simple infection by A. marginale through semi-nested PCR. These results confirm bovine anaplasmosis as the primary cause of CTF among the calves of dairy cattle within the studied area.(AU)

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O presente estudo teve como objetivo caracterizar a importância de Anaplasma marginale, Babesia bigemina e Babesia bovis na gênese da tristeza parasitária bovina em bezerros leiteiros do noroeste de Minas Gerais. Foram coletadas 300 amostras sanguíneas de bezerros, seguidas por extração de DNA e Nested- PCR utilizando oligonucleotídeos iniciadores que amplificam fragmentos dos genes sbp-4 (B. bovis) e rap-1a (B. bigemina) e a Semi-Nested para o gene msp5 (A. marginale). A prevalência de A. marginale foi 55,66% (167/300), B. bigemina, 15,33% (46/300) e B. bovis 4,0% (12/300) dos bezerros examinados. Formas parasitárias de A. marginale and B. bigemina foram encontradas em 36,33% e 2,66% dos esfregaços sanguíneos, enquanto B. bovis não foi detectado. Houve diferença estatística entre as prevalências de animais infectados nas faixas etárias 1 (10-70 dias) e 2 (>70-300 dias). Um total de 15 animais com sintomas clássicos da doença foram examinados, e as amostras foram confirmadas como uma infecção simples por A. marginale através da Nested-PCR. Esses resultados confirmam a anaplasmose bovina como a principal agente da tristeza parasitária bovina nos bezerros do rebanho estudado.(AU)

Asunto(s)

Animales , Bovinos , Bovinos/parasitología , Enfermedades por Picaduras de Garrapatas/diagnóstico , Enfermedades por Picaduras de Garrapatas/parasitología , Anaplasma marginale/clasificación

RESUMEN

The present study aimed to characterize the importance of the Anaplasma marginale, Babesia bovis and Babesia bigemina in the genesis of cattle tick fever (CTF) among dairy calves in the northwest of Minas Gerais, Brazil. Blood samples from 300 calves were collected, followed by DNA extraction and nested PCR using oligonucleotide primers to amplify fragments of the semi-nested for the msp5 gene (A. marginale), sbp-4 (B. bovis) and rap-1a (B. bigemina) Among the examined calves, the prevalence of A. marginale was 55.6% (n=167/300), B. bovis was 4.0% (n=12/300) and B. bigemina was 15.3% (n=46/300), by PCR techniques. Parasitic forms of A. marginale and B. bigemina were found in 36,3% and 2,6% of the blood smears while B. bovis was not detected. There was a statistical difference between the positivity of infected animals in the age groups 1 (10-70 days) and (>70-300 days) for A. marginale and B. bigemina. A total of 15 calves with the classic symptoms of disease were examined, and the samples obtained were confirmed as a simple infection by A. marginale through semi-nested PCR. These results confirm bovine anaplasmosis as the primary cause of CTF among the calves of dairy cattle within the studied area.(AU)

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O presente estudo teve como objetivo caracterizar a importância de Anaplasma marginale, Babesia bigemina e Babesia bovis na gênese da tristeza parasitária bovina em bezerros leiteiros do noroeste de Minas Gerais. Foram coletadas 300 amostras sanguíneas de bezerros, seguidas por extração de DNA e Nested- PCR utilizando oligonucleotídeos iniciadores que amplificam fragmentos dos genes sbp-4 (B. bovis) e rap-1a (B. bigemina) e a Semi-Nested para o gene msp5 (A. marginale). A prevalência de A. marginale foi 55,66% (167/300), B. bigemina, 15,33% (46/300) e B. bovis 4,0% (12/300) dos bezerros examinados. Formas parasitárias de A. marginale and B. bigemina foram encontradas em 36,33% e 2,66% dos esfregaços sanguíneos, enquanto B. bovis não foi detectado. Houve diferença estatística entre as prevalências de animais infectados nas faixas etárias 1 (10-70 dias) e 2 (>70-300 dias). Um total de 15 animais com sintomas clássicos da doença foram examinados, e as amostras foram confirmadas como uma infecção simples por A. marginale através da Nested-PCR. Esses resultados confirmam a anaplasmose bovina como a principal agente da tristeza parasitária bovina nos bezerros do rebanho estudado.(AU)

Asunto(s)

Animales , Bovinos , Anaplasma marginale/clasificación , Babesia/clasificación , Bovinos/sangre , Bovinos/parasitología

RESUMEN

This study aims to evaluate the infection's clinical parameters and genetic diversity of msp1α of the AmRio1 strain in acute and chronic infections in cattle and ticks. A calf experimentally infected with the A. marginale AmRio1 strain was monitored during acute infection, and the presence of the msp1α gene was verified in the semi-nested polymerase chain reaction (PCR) during the acute and persistent phases of infection. From day seven after inoculation of the pathogen, the calf showed an increase in body temperature, decrease in hematocrit and increase in the percentage of cells infected by the agent, as well as clinical signs. Blood samples from the experimentally infected calf were positive during the acute infection and the persistent PCR infection for the msp1α gene. During the acute phase, infestation with Rhipicephalus microplus was performed. To evaluate the chronic phase, a blood sample was collected at 90 days post-infection. There was no variation of the MSP1a protein in this study. The AmRio1 strain was pathogenic as it caused severe changes in the clinical parameters of the monitored cattle. The positivity of this strain in organs and saliva of the analyzed ticks indicates a probable biological transmission.

Asunto(s)

Anaplasma marginale/genética , Anaplasmosis/microbiología , Vectores Arácnidos/microbiología , Proteínas de la Membrana Bacteriana Externa/genética , Enfermedades de los Bovinos/microbiología , Rhipicephalus/microbiología , Secuencia de Aminoácidos , Anaplasma marginale/clasificación , Anaplasmosis/transmisión , Animales , Proteínas de la Membrana Bacteriana Externa/química , Bovinos , Enfermedades de los Bovinos/sangre , Enfermedades de los Bovinos/transmisión , Reacción en Cadena de la Polimerasa , Saliva/microbiología

RESUMEN

Este estudo avaliou a incidência de infecções naturais pelos agentes da tristeza parasitária bovina (TPB), Anaplasma marginale, Babesia bovis e Babesia bigemina, em bezerros nascidos em cinco fazendas do semiárido paraibano. Em cada fazenda, foram coletadas amostras de sangue de 6 a 14 bezerros a cada 14 dias durante os primeiros 12 meses de vida de cada animal. As amostras de sangue foram processadas por microhematócrito e testadas por PCR para detecção de DNA de A. marginale, B. bovis e B. bigemina. Em paralelo, foram quantificadas as infestações por carrapatos nos bovinos nas cinco fazendas, assim como as populações de tabanídeos em três fazendas. De 41 bezerros monitorados durante o primeiro ano de vida, 25 (61,0%) apresentaram PCR positivo para A. marginale, 7 (17,1%) para B. bigemina e 3 (7,3%) para B. bovis. Os valores de incidência da infecção por A. marginale variaram de 83,3% a 100% em quatro fazendas. A infecção por B. bigemina ocorreu em bezerros de apenas duas fazendas (incidências de 12,5% e 85,7%) e a por B. bovis em apenas uma (incidência de 42,8%). Em uma fazenda os 14 bezerros permaneceram negativos para A. marginale, B. bigemina e B. bovis durante os 12 meses de acompanhamento. Os resultados de PCR foram confirmados por sequenciamento de DNA de produtos amplificados. A presença de carrapatos Rhipicephalus (Boophilus) microplus foi verificada somente em duas propriedades, nas quais houve infecção por A. marginale, B. bigemina e B. bovis (este último agente em apenas uma delas). Foram capturados 930 tabanídeos no estudo, a maioria durante os períodos de chuvas na região; 70,7% dos tabanídeos corresponderam a Tabanus claripennis. Houve associação significativa entre PCR positivo para A. marginale ou B. bigemina e menores valores de hematócrito... (AU)

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This study evaluated the incidence of natural infection by agents of cattle tick fever (CTF), Anaplasma marginale, Babesia bovis and Babesia bigemina in calves born in five farms within the semiarid region of Paraíba state, Brazil. In each farm, blood samples were collected from 6 to 14 calves every 14 days during the first 12 months of life of each animal. Blood samples were processed by microhematocrit and tested by PCR for detection of DNA of A. marginale, B. bovis and B. bigemina. In parallel, the tick infestations on animals were quantified in the five farms, as well as populations in horseflies in three farms. From a total of 41 calves monitored during the first year of life, 25 (61.0%) had positive PCR for A. marginale, 7 (17.1%) for B. bigemina and 3 (7.3%) to B. bovis. Incidence values for A. marginale infection ranged from 83.3% to 100% in four farms. Infection with B. bigemina in calves was detected at only two farms (incidence of 12.5% and 85.7%) and by B. bovis in just one (42.8% incidence). On one farm 14 calves remained negative for A. marginale, B. bigemina and B. bovis during the 12 month follow-up. PCR results were confirmed by DNA sequencing of amplified products. The presence of Rhipicephalus (Boophilus) microplus was found only in two farms in which there was infection by A. marginale, B. bigemina and B. bovis (the latter agent in only one of them). A total of 930 horseflies were captured in the study, most during periods of rain in the region; 70.7% of horseflies corresponded to Tabanus claripennis. There was significant association between a positive PCR for A. marginale and B. bigemina and lower hematocrit values. This study demonstrates that even evaluating only five rural properties, the incidence of CTF occurred heterogeneously in the region, confirming the status of enzootic instability area for CTF, previously reported for the semiarid region of Paraiba.(AU)

Asunto(s)

Animales , Lactante , Bovinos , Babesia/clasificación , Bovinos/parasitología , Anaplasma marginale/clasificación

RESUMEN

Este estudo avaliou a incidência de infecções naturais pelos agentes da tristeza parasitária bovina (TPB), Anaplasma marginale, Babesia bovis e Babesia bigemina, em bezerros nascidos em cinco fazendas do semiárido paraibano. Em cada fazenda, foram coletadas amostras de sangue de 6 a 14 bezerros a cada 14 dias durante os primeiros 12 meses de vida de cada animal. As amostras de sangue foram processadas por microhematócrito e testadas por PCR para detecção de DNA de A. marginale, B. bovis e B. bigemina. Em paralelo, foram quantificadas as infestações por carrapatos nos bovinos nas cinco fazendas, assim como as populações de tabanídeos em três fazendas. De 41 bezerros monitorados durante o primeiro ano de vida, 25 (61,0%) apresentaram PCR positivo para A. marginale, 7 (17,1%) para B. bigemina e 3 (7,3%) para B. bovis. Os valores de incidência da infecção por A. marginale variaram de 83,3% a 100% em quatro fazendas. A infecção por B. bigemina ocorreu em bezerros de apenas duas fazendas (incidências de 12,5% e 85,7%) e a por B. bovis em apenas uma (incidência de 42,8%). Em uma fazenda os 14 bezerros permaneceram negativos para A. marginale, B. bigemina e B. bovis durante os 12 meses de acompanhamento. Os resultados de PCR foram confirmados por sequenciamento de DNA de produtos amplificados. A presença de carrapatos Rhipicephalus (Boophilus) microplus foi verificada somente em duas propriedades, nas quais houve infecção por A. marginale, B. bigemina e B. bovis (este último agente em apenas uma delas). Foram capturados 930 tabanídeos no estudo, a maioria durante os períodos de chuvas na região; 70,7% dos tabanídeos corresponderam a Tabanus claripennis. Houve associação significativa entre PCR positivo para A. marginale ou B. bigemina e menores valores de hematócrito. Este estudo demonstra que, mesmo avaliando apenas cinco propriedades rurais, a incidência dos agentes da TPB ocorreu de forma heterogênea na região, corroborando o status de área de instabilidade enzoótica para TPB previamente relatado para o semiárido paraibano.(AU)

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This study evaluated the incidence of natural infection by agents of cattle tick fever (CTF), Anaplasma marginale, Babesia bovis and Babesia bigemina in calves born in five farms within the semiarid region of Paraíba state, Brazil. In each farm, blood samples were collected from 6 to 14 calves every 14 days during the first 12 months of life of each animal. Blood samples were processed by microhematocrit and tested by PCR for detection of DNA of A. marginale, B. bovis and B. bigemina. In parallel, the tick infestations on animals were quantified in the five farms, as well as populations in horseflies in three farms. From a total of 41 calves monitored during the first year of life, 25 (61.0%) had positive PCR for A. marginale, 7 (17.1%) for B. bigemina and 3 (7.3%) to B. bovis. Incidence values for A. marginale infection ranged from 83.3% to 100% in four farms. Infection with B. bigemina in calves was detected at only two farms (incidence of 12.5% and 85.7%) and by B. bovis in just one (42.8% incidence). On one farm 14 calves remained negative for A. marginale, B. bigemina and B. bovis during the 12 month follow-up. PCR results were confirmed by DNA sequencing of amplified products. The presence of Rhipicephalus (Boophilus) microplus was found only in two farms in which there was infection by A. marginale, B. bigemina and B. bovis (the latter agent in only one of them). A total of 930 horseflies were captured in the study, most during periods of rain in the region; 70.7% of horseflies corresponded to Tabanus claripennis. There was significant association between a positive PCR for A. marginale and B. bigemina and lower hematocrit values. This study demonstrates that even evaluating only five rural properties, the incidence of CTF occurred heterogeneously in the region, confirming the status of enzootic instability area for CTF, previously reported for the semiarid region of Paraiba.(AU)

Asunto(s)

Animales , Lactante , Bovinos , Babesia/clasificación , Bovinos/parasitología , Anaplasma marginale/clasificación

RESUMEN

BACKGROUND: Anaplasma marginale is a well-known cattle pathogen of tropical and subtropical world regions. Even though, this obligate intracellular bacterium has been reported in other host species different than bovine, it has never been documented in Myrmecophaga tridactyla (giant anteater) or Hippocamelus antisense (taruca), which are two native endangered species. METHODS: Samples from two sick wild animals: a Myrmecophaga tridactyla (blood) and a Hippocamelus antisense (blood and serum) were studied for the presence of A. marginale DNA through msp5 gene fragment amplification. Further characterization was done through MSP1a tandem repeats analysis and MLST scheme and the genetic relationship among previously characterized A. marginale sequences were studied by applying, eBURST algorithm and AMOVA analysis. RESULTS: Anaplasma marginale DNA was identified in the Myrmecophaga tridactyla and Hippocamelus antisense samples. Through molecular markers, we identified an identical genotype in both animals that was not previously reported in bovine host. The analysis through eBURST and AMOVA revealed no differentiation between the taruca/anteater isolate and the bovine group. CONCLUSIONS: In the present publication we report the identification of A. marginale DNA in a novel ruminant (Hippocamelus antisense) and non-ruminant (Myrmecophaga tridactyla) host species. Genotyping analysis of isolates demonstrated the close relatedness of the new isolate with the circulation population of A. marginale in livestock. Further analysis is needed to understand whether these two hosts contribute to the anaplasmosis epidemiology.

Asunto(s)

Anaplasma marginale/clasificación , Anaplasmosis/microbiología , Artiodáctilos/microbiología , Enfermedades de los Bovinos/microbiología , Xenarthra/microbiología , Anaplasma marginale/aislamiento & purificación , Animales , Proteínas de la Membrana Bacteriana Externa/genética , Bovinos , ADN Bacteriano/sangre , Femenino , Genotipo , Especificidad del Huésped , Tipificación de Secuencias Multilocus/veterinaria , Filogenia , Análisis de Secuencia de ADN/veterinaria , Secuencias Repetidas en Tándem/genética

RESUMEN

Bovine tick-borne disease (TBD) constitutes a worldwide group of diseases that result in great losses for dairy and beef cattle. With regard to the epidemiological profile of the diseases, the importance of transplacental transmission is still not very well understood. The aim of this study was to determine the transplacental transmission of TBD agents (Anaplasma marginale, Babesia bovis and B. bigemina) in a herd of dairy cattle that had been naturally infected in an area of enzootic stability in northeastern Brazil. Blood for serology of the three agents was collected from cows within 120 days of gestation and serology, haemogram and nPCR assays were performed after birth. Blood was collected from the calves within 3h of birth, and haemogram and nPCR assays were performed in all animals. Pre-colostrum serology was achieved in 34 animals. The Student's t-test was used to compare the haemogram results between animals that were positive and negative for the haemoparasites. The cows were seropositive for all agents in at least one of the examinations. We detected 15 cases of vertical transmission of A. marginale, 4 of B. bovis and 2 of B. bigemina in the 60 cows. In infected animals, co-infection was detected for A. marginale and B. bovis in 1 of 60 calves, and a triple infection was detected in one other calf. Fatal neonatal anaplasmosis was observed in 1 of 15 calves, in which death occurred within 24h of birth. From the results, we concluded that transplacental transmission of TBD agents occurs, including in cases of co- and triple-infection. Such transplacental transmission can cause neonatal death, increasing the importance of this form of epidemiological transmission and suggesting its role as a cause of undiagnosed neonatal death.

Asunto(s)

Vectores Arácnidos , Enfermedades de los Bovinos/transmisión , Transmisión Vertical de Enfermedad Infecciosa/veterinaria , Enfermedades por Picaduras de Garrapatas/veterinaria , Garrapatas , Anaplasma marginale/clasificación , Anaplasma marginale/genética , Anaplasma marginale/inmunología , Anaplasma marginale/aislamiento & purificación , Anaplasmosis/epidemiología , Anaplasmosis/transmisión , Animales , Animales Recién Nacidos , Vectores Arácnidos/microbiología , Vectores Arácnidos/parasitología , Babesia/genética , Babesia/inmunología , Babesia/aislamiento & purificación , Babesia bovis/genética , Babesia bovis/inmunología , Babesia bovis/aislamiento & purificación , Babesiosis/epidemiología , Babesiosis/transmisión , Brasil/epidemiología , Bovinos , Enfermedades de los Bovinos/epidemiología , Coinfección/veterinaria , Enfermedades Endémicas/veterinaria , Femenino , Filogenia , Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/transmisión , Garrapatas/microbiología , Garrapatas/parasitología

RESUMEN

The present study reports the genetic diversity of Anaplasma marginale during anaplasmosis outbreaks in rural properties of the states of Goiás and São Paulo, Brazil. Mortality rates of 3.5% (37/1,050) in calves, 4.7% (45/954) in heifers and 1.1% (25/2,200) in lactating cows were observed in a cattle herd of the municipality of Mambaí, state of Goiás, central-western Brazil. In a cattle herd from the municipality of Lins, state of São Paulo, in southeastern Brazil, none of the animals died, despite presenting clinical signs suggestive of bovine anaplasmosis and exhibiting a drastic decrease in milk production. Thus, blood samples were collected from 100 animals with clinical signs suggestive of bovine anaplasmosis in the municipalities of Mambaí and Lins. Based on the microsatellite structure of the MSP1a of A. marginale, the genotypes E and H were observed in Lins, and the C, D and E genotypes were found in Mambaí. The analysis of the tandem repeat structures of the MSP1a showed nine different strains (τ-10 -15, α-ß2, α-ß3-13, α-ß2 192, τ-ß-100, α-ß2-Γ, 193-ß-100, 191-13-Γ and 191-13-18) in Lins and two (α-ß3-Γ and E-F-φ2-F2) in Mambaí. Three new tandem repeats of MSP1a (191, 192 and 193) were described. The τ-10-15 and α-ß3-Γ strains were predominantly associated with the occurrence of clinical anaplasmosis and mortality in calves, heifers and lactating cows.

Asunto(s)

Anaplasma marginale , Anaplasmosis/epidemiología , Enfermedades de los Bovinos/epidemiología , Brotes de Enfermedades/veterinaria , Anaplasma marginale/clasificación , Anaplasmosis/parasitología , Animales , Brasil/epidemiología , Bovinos , Enfermedades de los Bovinos/parasitología , Femenino , Lactancia , Filogenia , Especificidad de la Especie

RESUMEN

Abstract The present study reports the genetic diversity of Anaplasma marginale during anaplasmosis outbreaks in rural properties of the states of Goiás and São Paulo, Brazil. Mortality rates of 3.5% (37/1,050) in calves, 4.7% (45/954) in heifers and 1.1% (25/2,200) in lactating cows were observed in a cattle herd of the municipality of Mambaí, state of Goiás, central-western Brazil. In a cattle herd from the municipality of Lins, state of São Paulo, in southeastern Brazil, none of the animals died, despite presenting clinical signs suggestive of bovine anaplasmosis and exhibiting a drastic decrease in milk production. Thus, blood samples were collected from 100 animals with clinical signs suggestive of bovine anaplasmosis in the municipalities of Mambaí and Lins. Based on the microsatellite structure of the MSP1a of A. marginale, the genotypes E and H were observed in Lins, and the C, D and E genotypes were found in Mambaí. The analysis of the tandem repeat structures of the MSP1a showed nine different strains (τ-10 -15, α-β2, α-β3-13, α-β2 192, τ-β-100, α-β2-Γ, 193-β-100, 191-13-Γ and 191-13-18) in Lins and two (α-β3-Γ and E-F-φ2-F2) in Mambaí. Three new tandem repeats of MSP1a (191, 192 and 193) were described. The τ-10-15 and α-β3-Γ strains were predominantly associated with the occurrence of clinical anaplasmosis and mortality in calves, heifers and lactating cows.

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Resumo O presente estudo relata a diversidade genética de Anaplasma marginale durante surtos de anaplasmose bovina no Brasil em propriedades localizadas nos Estados de Goiás e São Paulo. No rebanho bovino de Mambaí, Estado de Goiás, Centro-oeste do Brasil, observaram-se taxas de mortalidade de 3,5% (37/1050) nos bezerros; 4,7% (45/954) nas novilhas e 1,1% (25/2200) nas vacas em lactação. No rebanho bovino de Lins, Estado de São Paulo, Sudeste do Brasil, embora os animais tenham apresentado sinais clínicos sugestivos de anaplasmose bovina, culminando em redução drástica da produção leiteira, nenhum animal veio a óbito. Assim, amostras de sangue de 100 bovinos com sinais clínicos sugestivos de anaplasmose foram coletadas em Mambaí-GO e Lins-SP. Baseando-se na estrutura do microssatélite da MSP1a de A. marginale, observou-se a presença dos genótipos E e H em Lins e C, D e E em Mambaí. A análise da estrutura em “tandem repeats” da MSP1a mostrou nove diferentes estirpes (τ-10 -15, α-β2, α-β3-13, α-β2 192, τ-β-100, α-β2-Γ, 193-β-100, 191-13-Γ e 191-13-18) em Lins e duas (α-β3-Γ e E-F-φ2-F2) em Mambaí. Três novos “tandem repeats” da MSP1a (191, 192 e 193) foram descritos. Foi observado predomínio das estirpes τ-10-15 e α-β3-Γ associado à ocorrência de anaplasmose clínica e mortalidade em bezerras, novilhas e vacas em lactação.

Asunto(s)

Animales , Femenino , Bovinos , Enfermedades de los Bovinos/epidemiología , Brotes de Enfermedades/veterinaria , Anaplasma marginale/clasificación , Anaplasmosis/epidemiología , Filogenia , Especificidad de la Especie , Brasil/epidemiología , Lactancia , Enfermedades de los Bovinos/parasitología , Anaplasmosis/parasitología

RESUMEN

Anaplasma marginale is the most prevalent tick-borne pathogen in cattle in tropical and subtropical regions of the world. Major Surface Protein 1a (MSP1a) has been found to be a stable genetic marker for identifying A. marginale isolates within geographical regions. It is conserved in cattle during infection and tick-borne transmission of the pathogen. The aim of the present longitudinal study was to determine occurrences of genetic diversity associated with high prevalence of A. marginale under natural transmission conditions. Twenty calves were evaluated every 3 months during the first year of life. Rickettsemia levels due to A. marginale, measured as the number of msp1αcopies/ml in the blood of positive calves, ranged from 2.06×10(3) to 4.36×10(12). The numbers of MSP1a tandem repeats among MSP1a tandem repeats were 3 and 6. The predominant msp1α microsatellite was E, and another MSP1a tandem repeat was found that presented genotype G. Nineteen different MSP1a tandem repeats of A. marginale were found circulating in animals. The MSP1a tandem repeats 4-63-27 (27.5%), 78-24(2)-25-31 (n=21.6%) and τ-10(2)-15 (n=17.6%) were the ones most commonly observed. Twenty-two MSP1a tandem repeats resulted in new sequences with amino acid changes, as shown in this study. Thirty sequences were found for the first time in Brazil. Glycine, glutamate, serine and alanine amino acids were found at position 20. During the study, 80% (16/20) of the animals were infected by more than one genotype. Three animals were born infected, with MSP1a tandem repeats 4-63-27, 78-24(2)-25-31 and τ-10(2)-15, thus indicating occurrence of transplacental transmission. In the phylogenetic analysis, 19 different MSP1a tandem repeats of A. marginale were found in the cattle, which suggested that many MSP1a tandem repeats and high variation in MSP1a were occurring.

Asunto(s)

Anaplasma marginale/clasificación , Anaplasma marginale/genética , Anaplasmosis/microbiología , Enfermedades de los Bovinos/microbiología , Variación Genética , Filogenia , Secuencia de Aminoácidos , Anaplasma marginale/química , Anaplasma marginale/aislamiento & purificación , Anaplasmosis/epidemiología , Anaplasmosis/transmisión , Animales , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Brasil/epidemiología , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/transmisión , Femenino , Genotipo , Estudios Longitudinales , Masculino , Repeticiones de Microsatélite , Datos de Secuencia Molecular , Alineación de Secuencia

RESUMEN

Anaplasma marginale is an economically important tick-borne pathogen of cattle that causes bovine anaplasmosis. A wide range of geographic strains of A. marginale have been isolated from cattle, several of which have been characterized using genomics and proteomics. While many of these strains have been propagated in tick lines, comparative analyses after propagation in tick cells have not been reported. The overall purpose of this research therefore was to compare the degree of conservation of selected genes after propagation in tick cell culture among A. marginale strains from the U.S. (the Virginia strain) and Brazil (UFMG1 and UFMG2 strains). The genes studied herein included those which encode the proteins HSP70 and SODB involved in heat shock and stress responses, respectively, and two genes that encode major surface proteins MSP4 and MSP5. Strain identities were first confirmed by sequencing the tandem repeats of the msp1a gene which encodes for the adhesin, MSP1a. The results of these studies demonstrated that the genes encoding for both stress response and heat shock proteins were highly conserved among the three A. marginale strains. Antibodies specific for MSP4, MSP5, SODB and HSP70 proteins were used to further characterize the A. marginale strains, and they reacted with all of these strains propagated in tick cell culture, providing further evidence for antigenic conservation. Although antigenic differences were not found among the three A. marginale strains, multi-locus sequence analysis (MLSA) performed with nucleotide sequences of these genes demonstrated that the A. marginale Brazilian and U.S. strains fall in different clades. These results showed that phylogenetically distant strains of A. marginale are antigenically conserved, even after several in vitro passages, supporting the use of some of the above conserved proteins as candidates for universal vaccines.

Asunto(s)

Anaplasma marginale/aislamiento & purificación , Anaplasmosis/inmunología , Vectores Arácnidos/microbiología , Proteínas Bacterianas/genética , Proteínas Bacterianas/inmunología , Enfermedades de los Bovinos/inmunología , Garrapatas/microbiología , Anaplasma marginale/clasificación , Anaplasma marginale/genética , Anaplasma marginale/crecimiento & desarrollo , Anaplasmosis/microbiología , Animales , Variación Antigénica , Brasil , Bovinos , Enfermedades de los Bovinos/microbiología , Secuencia Conservada , Datos de Secuencia Molecular , Filogenia , Estados Unidos

RESUMEN

A study was conducted in 2008 to determine the prevalence of Anaplasma and Babesia infections in cattle in the Puntarenas Province of Costa Rica. Blood samples were taken from a total of 449 cattle during the month of March at 30 farms in the region of Espiritu Santu, Costa Rica. Commercially available enzyme-linked immunosorbent assays (ELISA) were used to determine presence of antibodies to Babesia bigemina and Anaplasma marginale, and real-time PCR was used to determine the presence of DNA from the disease-causing organisms. The ELISA results indicated that 87.5% of the cattle sampled were positive for antibodies to A. marginale, while 59.1% were positive for antibodies to B. bigemina. The real-time PCR results showed that 235 cattle were carrying A. marginale DNA (56.9%), 6 with B. bigemina DNA (1.34%), and 2 with B. bovis DNA (0.45%).

Asunto(s)

Anaplasma marginale/aislamiento & purificación , Babesia/aislamiento & purificación , Babesiosis/veterinaria , Anaplasma marginale/clasificación , Animales , Babesia/clasificación , Babesiosis/epidemiología , Babesiosis/parasitología , Bovinos , Costa Rica/epidemiología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Prevalencia , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria

RESUMEN

Anaplasma marginale is an obligate intraerythrocytic rickettsial pathogen (order, Rickettsiales: family, Anaplasmataceae) that causes bovine anaplasmosis. This disease is widely distributed in tropical and sub-tropical regions of the world and causes important economic losses to cattle production. Major surface protein (MSP)1a (msp1alpha gene) is one of the six MSPs identified on A. marginale from cattle, whose sequence and size vary according to the number of tandem 28- to 29-amino acid repeats. This study characterized the msp1alpha and msp4 genes obtained from three distinct Brazilian herds from the State of Paraná. Three strains of the msp1alpha and one strain of the msp4 gene were sequenced. The strains evaluated revealed PCR products of different size, representing three, five and six internal repeats. Sequence analyses confirmed the number of tandem sequence copies and revealed a high degree of sequence identity with strains from other Brazilian States, as well as strains from the USA, Europe and Israel. The msp1alpha DNA and amino acid sequences from A. marginale and DNA sequences of msp4 strains did not reveal distinct phylogeographical segregation. However, the amino acid sequences of msp4 demonstrated definite phylogeographical relationship. These results suggest that the amino acid sequences of msp4 should be used for phylogenetic identification of A. marginale strains and may be an important tool for the epidemiology and control of anaplasmosis. Additionally, the close similarity of the Paraná strains of A. marginale with strains from USA, Europe and Asia may reflect the introduction of these genes during the development of the Brazilian bovine herd.

Asunto(s)

Anaplasma marginale/clasificación , Anaplasma marginale/genética , Anaplasmosis/microbiología , Enfermedades de los Bovinos/microbiología , Filogenia , Secuencia de Aminoácidos , Animales , Proteínas Bacterianas/análisis , Proteínas Bacterianas/genética , Brasil , Bovinos , ADN Bacteriano/química , ADN Bacteriano/genética , Geografía , Datos de Secuencia Molecular , Enfermedades por Picaduras de Garrapatas/microbiología

RESUMEN

In Mexico, there are no commercial alternatives for the immunoprophylaxis of bovine Anaplasmosis, a disease responsible for great economic losses. Blood derived Anaplasma marginale used for immunizing susceptible cattle has shown promising results for homologous protection and controversial results against unrelated strains. The present study examined, under controlled conditions, the cross-protective potential of an immunogen composed of blood derived A. marginale of three strains against challenge with strains not included in the immunogens. Groups 1 and 2 were immunized with blood derived Anaplasma from strains Mexico, Morelos and Yucatan, group 4 with strains Morelos, Veracruz and Yucatan, two more groups (2 and 5) of equal conditions were inoculated with an adjuvant alone. Groups 1, 4 and 5 were challenged with Mexico strain; groups 2 and 3 were challenge-inoculated with strain Veracruz; groups 3 and 5 with strains Veracruz and Mexico as controls. Only animals in group 1, immunized and challenged with strain Mexico showed adequate protection. Both groups challenged with strains not included in the immunogens developed poor protection, while all the controls had to be treated to prevent death.

Asunto(s)

Anaplasma marginale/inmunología , Anaplasmosis/prevención & control , Proteínas de la Membrana Bacteriana Externa/inmunología , Proteínas Bacterianas/inmunología , Enfermedades de los Bovinos/prevención & control , Proteínas de la Membrana/inmunología , Vacunación/veterinaria , Anaplasma marginale/clasificación , Anaplasma marginale/patogenicidad , Anaplasmosis/inmunología , Anaplasmosis/microbiología , Animales , Vacunas Bacterianas/inmunología , Bovinos , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/microbiología , Eritrocitos/microbiología , Femenino