Occurrence of antibodies anti-Toxoplasma gondii and anti-Neospora caninum in dogs from Natal, RN, Brazil

The occurrence of anti-Toxoplasma gondii and Neospora caninum in dogs from the municipality of Natal, RN, Brazil, was determined. Information about the presence of these coccidia in this species was not known. Blood samples were collected from 29 domiciled dogs which inhabit areas that surround two important protected areas of Atlantic Forest (Parque da Cidade and Parque das Dunas) and another 73 dogs that were sacrificed due to Leishmania spp. infection, in Center for Control of Zoonosis (CCZ) for the municipality of Natal. It was only possible to obtain information about the gender of dogs that live in the parks area. The presence of antibodies against each parasite was determined by indirect Fluorescence Antibody Test (IFAT), with a cutoff of 16 for T. gondii and 50 for N. caninum. Of the 102 dogs examined, 13 (12.7%, 95% CI 7.0-20.8%) were T. gondii positive and three (2.9%, CI 0.6-8.4%) for N. caninum. Association between: localities of obtaining samples (parks x CCZ) and sex of animals, with the occurrence of antibodies against each of the parasites, was determined by the Fisher exact test. For T. gondii association was found with males (p = 0.027) and dogs living close to parks (p = 0.008) had higher rates of infection. Associations were not observed in relation to N. caninum.A ocorrência de anticorpos anti-Toxoplasma gondii e anti-Neospora caninum foi determinada em cães do município de Natal, RN, onde informações sobre a presença destes coccídios nessa espécie não era conhecida. Para tanto, foram utilizados 29 cães domiciliados, que habitam áreas que circundam duas importantes Unidades de Conservação de Mata Atlântica presentes no município (Parque da Cidade e Parque das Dunas), e outros 73 cães que foram sacrificados no Centro de Controle de Zoonoses de Natal por serem positivos a Leishmania spp. Somente em relação aos cães que vivem próximos aos parques foi possível a obtenção de informações sobre o sexo dos animais. A presença de anticorpos contra cada um dos coccídios foi determinada com a Reação de Imunofluorescência Indireta com ponto de corte de 16 para T. gondii e 50 para N. caninum. Dos 102 cães examinados, 13 (12,7%, IC 95% 7,0-20,8) foram positivos para T. gondii e 3 (2,9%, IC 0,6-8,4%) para N. caninum. Associação entre: localidades de obtenção das amostras (parques x CCZ) e sexo dos animais com a ocorrência de anticorpos contra cada um dos parasitos, determinada através do teste exato de Fisher, foram positivas para T. gondii, com os machos (p = 0,027) e cães que habitam próximos aos parques (p = 0,008) apresentando maiores taxas de infecção. Associações não foram observadas em relação a N. caninum

Analysis of the cattle trade network in the state of Mato Grosso, Brazil

Caracterizamos a rede de trânsito de bovinos em Mato Grosso, Brasil – um estado responsável por uma quantidade significativa das exportações brasileiras de carne bovina. Nesta análise, o interesse foi na importância de abatedouros na rede de trânsito de bovinos, nas características do comércio para diferentes finalidades (especialmente para reprodução, engorda e abate), e sobre a importância dos principais comerciantes. Encontramos que a distância mediana de todos os movimentos foi de 79,0 km, com um intervalo interquartil entre 37,2 e 163,2 km, o que sugere um padrão de comércio de alcance relativamente curto; cerca de 20% dos estabelecimentos que compram mais animais foram responsáveis por 95% dos animais comprados e 20% dos estabelecimentos que vendem mais animais foram responsáveis por 86% dos animais vendidos, o que mostra a importância dos principais comerciantes de bovinos. Ajustando a distribuição de graus usando uma distribuição de lei de potência, obtivemos um parâmetro de escala de 2,59, indicando que a rede de movimentação de bovinos de Mato Grosso é menos densa do que outras redes de trânsito bovino observadas. As redes para engorda, reprodução e abate compreenderam 73%, 56% e 25% de todos os nós e 52%, 30% e 17% de todas as arestas, respectivamente; e os frigoríficos tiveram os mais altos graus de entrada e totais, seguidos por mercados e fazendas, desempenhando o papel de principais pontos de comércio de gado. Por conseguinte, abatedouros são potencialmente úteis como pontos de vigilância para detectar casos, e o controle de estabelecimentos importantes para o comércio pode otimizar o uso de recursos para o controle de doenças.We characterized the network of cattle movements in Mato Grosso, Brazil—a state responsible for a significant amount of Brazilian beef exports. In this analysis, we were particularly interested in the importance of slaughterhouses in the network of cattle movements, in the characteristics of the trade for different purposes (especially for reproduction, fattening, and slaughter), and about the importance of the main traders. We found that the median distance of all movements was 79.0 km, with an interquartile range between 37.2 and 163.2 km, which suggests a relatively short-range trade pattern; roughly 20% of the premises purchasing more animals were responsible for 95% of the animals purchased and 20% of the premises selling more animals were responsible for 86% of the animals sold, indicating the importance of the cattle trade hubs. Fitting the degree distribution using a power-law distribution, we obtained a scaling parameter of 2.59, indicating that the cattle movement network of Mato Grosso is less dense than other observed cattle movement networks. The networks for fattening, reproduction, and slaughtering only comprised 73%, 56%, and 25% of all nodes and 52%, 30%, and 17% of all edges, respectively; and slaughterhouses had the highest in-degrees and total degrees, followed by markets and farms, playing the role of main cattle trade hubs. Therefore, slaughterhouses are potentially useful as surveillance points to detect cases, and controlling important trader premises may optimize the use of resources for controlling diseases

Use of geographic information systems in rabies vaccination campaigns

OBJETIVO: Desenvolver método para planejamento e avaliação de campanhas de vacinação contra a raiva animal. MÉTODOS: O desenvolvimento da metodologia baseou-se em sistemas de informação geográfica para estimar a população e a densidade animal (canina e felina) por setores censitários e subprefeituras do município de São Paulo, em 2002. O número de postos de vacinação foi estimado para atingir uma dada cobertura vacinal. Foram utilizadas uma base de dados censitários para a população humana, e estimativas para razões cão:habitante e gato:habitante. RESULTADOS: Os números estimados foram de 1.490.500 cães e 226.954 gatos em São Paulo, uma densidade populacional de 1.138,14 animais domiciliados por km2. Foram vacinados, na campanha de 2002, 926.462 animais, garantindo uma cobertura vacinal de 54%. O número total estimado de postos no município para atingir uma cobertura vacinal de 70%, vacinando em média 700 animais por posto foi de 1.729. Estas estimativas foram apresentadas em mapas de densidade animal, segundo setores censitários e subprefeituras. CONCLUSÕES: A metodologia desenvolvida pode ser aplicada de forma sistemática no planejamento e no acompanhamento das campanhas de vacinação contra a raiva, permitindo que sejam identificadas áreas de cobertura vacinal críticaTo develop a method to assist in the design and assessment of animal rabies control campaigns. METHODS: A methodology was developed based on geographic information systems to estimate the animal (canine and feline) population and density per census tract and per subregion (known as "Subprefeituras") in the city of São Paulo (Southeastern Brazil) in 2002. The number of vaccination units in a given region was estimated to achieve a certain proportion of vaccination coverage. Census database was used for the human population, as well as estimates ratios of dog:inhabitant and cat:inhabitant. RESULTS: Estimated figures were 1,490,500 dogs and 226,954 cats in the city, i.e. an animal population density of 1138.14 owned animals per km2. In the 2002 campaign, 926,462 were vaccinated, resulting in a vaccination coverage of 54%. The estimated number of vaccination units to be able to reach a 70%-vaccination coverage, by vaccinating 700 animals per unit on average, was 1,729. These estimates are presented as maps of animal density according to census tracts and "Subprefeituras". CONCLUSIONS: The methodology used in the study may be applied in a systematic way to the design and evaluation of rabies vaccination campaigns, enabling the identification of areas of critical vaccination coverag

Livestock markets play an important role in the cattle movement network in Pernambuco, Brazil

The animal trade is an important risk factor that affects the spread of diseases among animals and herds. The goal of the present study was to characterize the cattle movement network in Pernambuco, Brazil, based on the animal movement permits (Guias de Trânsito Animal; GTAs) from 2012 to 2013, and identify the intensity of the commercial relationship between farm premises. A total of 737,950 GTAs were issued, and the movement of 3,481,185 cattle (1,688,585 in 2012 and 1,792,600 in 2013) was analyzed. Of the moved animals analyzed, 52.57% (1,829,907/3,481,185) were involved in the movement of cattle in or out of livestock markets, indicating that livestock markets played a major role in the network. Approximately 20% of the more-connected premises were responsible for approximately 87% of the movement related to sales and 95% of the movement related to purchases. Considering the important role of livestock markets and the intense cattle trade between farm premises, surveillance, and control measures could be more efficient if targeted to livestock markets and highly connected premises to prevent the spread of infectious diseases.O comércio de animais é um importante fator de risco para a disseminação de doenças entre animais e rebanhos. O objetivo do presente estudo foi caracterizar a rede de movimentação de bovinos em Pernambuco, com base nas guias de trânsito animal (GTAs) de 2012 a 2013, e identificar a intensidade da relação comercial entre os estabelecimentos. Foram analisadas 737.950 GTAs emitidas, e as movimentações de bovinos totalizaram 3.481.185 animais (1.688.585 em 2012 e 1.792.600 em 2013). Um percentual de 52,57% (1.829.907/3.481.185) das movimentações de bovinos envolveu entrada ou saída de feiras de gado, indicando que as feiras desempenharam um papel importante na rede. Aproximadamente 20% dos estabelecimentos mais conectados foram responsáveis por aproximadamente 87% das movimentações relacionadas às vendas, e 95% das movimentações, relacionadas às compras. Considerando o importante papel das feiras e o intenso comércio de bovinos entre as propriedades, medidas de vigilância e controle podem ser mais eficientes se aplicadas em feiras e estabelecimentos altamente conectados, para prevenir a propagação de doenças infecciosas

Uso de sistemas de informação geográfica em campanhas de vacinação contra a raiva

OBJECTIVE: To develop a method to assist in the design and assessment of animal rabies control campaigns. METHODS: A methodology was developed based on geographic information systems to estimate the animal (canine and feline) population and density per census tract and per subregion (known as "Subprefeituras") in the city of São Paulo (Southeastern Brazil) in 2002. The number of vaccination units in a given region was estimated to achieve a certain proportion of vaccination coverage. Census database was used for the human population, as well as estimates ratios of dog:inhabitant and cat:inhabitant. RESULTS: Estimated figures were 1,490,500 dogs and 226,954 cats in the city, i.e. an animal population density of 1138.14 owned animals per km². In the 2002 campaign, 926,462 were vaccinated, resulting in a vaccination coverage of 54%. The estimated number of vaccination units to be able to reach a 70%-vaccination coverage, by vaccinating 700 animals per unit on average, was 1,729. These estimates are presented as maps of animal density according to census tracts and "Subprefeituras". CONCLUSIONS: The methodology used in the study may be applied in a systematic way to the design and evaluation of rabies vaccination campaigns, enabling the identification of areas of critical vaccination coverage.OBJETIVO: Desarrollar método para planificación y evaluación de campañas de vacunación contra la rabia animal. MÉTODOS: El desarrollo de la metodología se basó en sistemas de información geográfica para estimar la población y la densidad animal (canina y felina) por sectores censales y sub-prefecturas del municipio de Sao Paulo (Sureste de Brasil), en 2002. El número de puestos de vacunación fue estimado para atender una determinada cobertura de vacunación. Se utilizaron una base de datos censales para la población humana, y estimativas para razones perro: habitante y gato: habitante. RESULTADOS: Los números estimados fueron de 1.490.500 perros y 226.954 en Sao Paulo, una densidad poblacional de 1.138,14 animales domiciliados por km2. Fueron vacunados, en la campaña de 2002, 926.462 animales, garantizando una cobertura de vacunas de 54%. El número total estimado de puestos en el municipio para atender una cobertura de vacunación de 70%, vacunando en promedio 700 animales por puesto fue de 1.729. Estas estimaciones fueron presentadas en mapas de densidad animal, según sectores censales y sub-prefecturas. CONCLUSIONES: La metodología desarrollada puede ser aplicada de forma sistemática en la planificación y en el acompañamiento de las campañas de vacunación contra la rabia, permitiendo que sean identificadas áreas de cobertura de vacunación crítica.OBJETIVO: Desenvolver método para planejamento e avaliação de campanhas de vacinação contra a raiva animal. MÉTODOS: O desenvolvimento da metodologia baseou-se em sistemas de informação geográfica para estimar a população e a densidade animal (canina e felina) por setores censitários e subprefeituras do município de São Paulo, em 2002. O número de postos de vacinação foi estimado para atingir uma dada cobertura vacinal. Foram utilizadas uma base de dados censitários para a população humana, e estimativas para razões cão:habitante e gato:habitante. RESULTADOS: Os números estimados foram de 1.490.500 cães e 226.954 gatos em São Paulo, uma densidade populacional de 1.138,14 animais domiciliados por km². Foram vacinados, na campanha de 2002, 926.462 animais, garantindo uma cobertura vacinal de 54%. O número total estimado de postos no município para atingir uma cobertura vacinal de 70%, vacinando em média 700 animais por posto foi de 1.729. Estas estimativas foram apresentadas em mapas de densidade animal, segundo setores censitários e subprefeituras. CONCLUSÕES: A metodologia desenvolvida pode ser aplicada de forma sistemática no planejamento e no acompanhamento das campanhas de vacinação contra a raiva, permitindo que sejam identificadas áreas de cobertura vacinal crítica

Ultrasound Evaluation of Lung Fields in Healthy Dogs: Scanning Technic and Aspects of Normality.

Background: The ultrasound exam has always played a secondary role in pulmonary imaging, with its applicability restricted in emergency care to screen for pleural and/or pericardial effusion, pneumothorax and pulmonary contusion. The recognition of different reverberating artifacts arising from the normal aerated lungs (A lines) and in the presence of lungs with interstitial and/or alveolar infiltrates (B lines) led to wider application of the technique in patients with respiratory syndrome. The objective of this study was to describe the ultrasound imaging methodology and the aspects of the pleura, pleural space and lung fields in healthy dogs.Materials, Methods & Results: Twenty healthy dogs of different breeds and ages, males and females were evaluated in this study; good health status was confirmed by physical examination, electro and echocardiographic assessment, thoracic radiography and systemic arterial blood pressure measurements. Dogs were scanned by a single examiner experienced in diagnostic imaging and previously trained for 6 months in thoracic ultrasound image interpretation. A MyLab 40 with a microconvex multifrequency probe (5-8 MHz) was used in this study.  Evaluation was performed in an orthopneic position (standing or sternal recumbecy) under manual containment. Ultrasound examinations were based on the VetBLUE (Veterinary Bedside Lung Ultrasound Exam) protocol. Lung fields were regionally scanned at the 2nd-3rd, 4-5th, 6-7th and 8-9th intercostal spaces in the right and left hemithorax. A subxiphoid window was added to screen for free fluid in the pleural space and/or pericardial sac. Pleural sliding and A lines, that are hyperechoic parallel equidistant lines arising from the visceral pleura-lung interface could be easily seen at all intercostal spaces in all dogs in this sample, with more difficult visualization at the 2nd-3rd intercostal space. B lines were observed in seven out of twenty dogs (35%). However, this artifact was limited to one intercostal space and a maximum of two lines were detected per field. B line artifacts were more commonly seen in the right hemithorax, at the level of the 8-9th intercostal space however without significant differences. In the subxiphoid window evaluation A lines were not detected.Discussion: The observation of B lines in healthy dogs was previously described and as in our study there were no significant differences relative to B line observation relatively to the intercostal space neither between the right and the left hemithorax. B lines are generally associated with decreased pulmonary aeration in response to interstitial/alveolar infiltration, which generates reflections and comet tail artifacts. The low number of B lines observed in this study may be associated with larger veins or lymphatics vessels, focal interstitial thickening or microatelectasia. The high respiratory frequency does not interfere in the sonographic evaluation. The dyspnea presented for animals with acute respiratory syndromes can be aggravated in stress situations, such as the displacement to the radiology service and manipulation necessary to the radiographic projections. Regional scanning by some acoustic windows allows rapid assessment of the thorax, with significant contributions to decision making in emergency situations. However, ultrasonography does not eliminate the need for other imaging modalities such as radiography and computed tomography and should be seen as a screening tool for patients presenting with acute respiratory syndromes

Congenital Transmission of Toxoplasma gondii After Experimental Reinfection With Brazilian Typical Strains in Chronically Infected Sheep

Toxoplasma gondii is a cause of congenital diseases, miscarriages and stillbirths in production animals. In Brazil, non-archetypal genotypes of the parasite may be related to severe disease. Experimental infection with T. gondii was studied in sheep to analyse congenital transmission-related parameters in reinfections with different Brazilian parasite strains. Thirteen T. gondii-seronegative sheep were orally infected with 2 × 103oocysts for the primary infection: G1 (4 animals) were inoculated with TgCatBr71 strain (Type BrI genotype) and G2 andG3 (5 and 4 animals, respectively) withTgCatBr60 strain (Type BrIII genotype). After chronification of infection, the animals were impregnated. A second infection was performed after 60 days of gestation. TheG1 andG3 animals were inoculated withTgCatBr60BrIII and the G2 animals withTgCatBr71 BrI oocysts. The effects of reinfection were compared with a control group (5 animals) through physical examination, ultrasound imaging and serology. Ovine experimental infections were evaluated using mouse bioassays, molecular analysis, serological tests, histopathology, and immunohistochemistry. No abortions occurred; a seropositive lamb and a mummified fetus from G2-BrIIIxBrI were produced. The vertical transmission rate detected in lambs from chronically infected sheep was 31.6% (6/19). It is demonstrated that reinfection and subsequent congenital transmission occured in one sheep with a primary Brl infection challenged with BrIII genotype of T. gondii. In a twin pregnancy from G2-BrIIIxBrI, congenital transmission from a latent infection was detected in both lambs. Congenital transmission could not be tracked in three lambs. Overall, previous T. gondii infection may fail to protect against congenital transmission from a reinfection and primary infection induced insufficient protection against vertical transmission which must be taken into account in decision-making for the use of seropositive animals as breeders. Similar trials with larger groups and contemplating host cellular immune response studies should be conducted to evaluate the actual impact of T. gondii reinfection involving different strains in sheep

Characterization of production zones based on animal movement networks

Uma rede é um conjunto de nós conectados entre si através de um conjunto de arestas. Redes podem representar qualquer conjunto de objetos que possuam relações entre si. Comunidades são conjuntos de nós relacionados de uma maneira significativa, provavelmente compartilhando propriedades e/ou atuando de forma similar dentro de uma rede. Quando a análise de redes é aplicada ao estudo de padrões de movimentação animal, as unidades epidemiológicas de interesse (propriedades, estabelecimentos, municípios, estados, países, etc) são representadas como nós, enquanto a movimentação animal entre elas é representada através das arestas de uma rede. Descobrir a estrutura de uma rede, e portanto as preferências e rotas comerciais, pode ser útil para um pesquisador ou gestor de saúde animal. Foi implementado um algoritmo de detecção de comunidades para encontrar grupos de propriedades que é consistente com a definição de circuito pecuário, assumindo que uma comunidade é um grupo de nós (fazendas, abatedouros) no qual um animal vai mais provavelmente permanecer durante sua vida. Este algoritmo foi aplicado na rede interna de movimentação animal de 2007 do Estado do Mato Grosso. Esse banco de dados contém informação sobre 87.899 propriedades e 521.431 movimentações durante o ano, totalizando 15.844.779 de animais movimentados. O algoritmo de detecção de comunidades encontrou uma partição da rede que mostra um claro padrão geográfico e comercial, duas importantes características para aplicações em medicina veterinária preventiva, além de possuir uma interpretação clara e significativa em redes de comércio onde ligações se estabelecem a partir da escolha dos nós envolvidos.A network is a set of nodes that are linked together by a set of edges. Networks can represent any set of objects that have relations among themselves. Communities are sets of nodes that are related in an important way, probably sharing common properties and/or playing similar roles within a network. When network analysis is applied to study the livestock movement patterns, the epidemiological units of interest (farm premises, counties, states, countries, etc.) are represented as nodes, and animal movements between the nodes are represented as the edges of a network. Unraveling a network structure, and hence the trade preferences and pathways, could be very useful to a researcher or a decision-maker. We implemented a community detection algorithm to find livestock communities that is consistent with the definition of a livestock production zone, assuming that a community is a group of farm premises in which an animal is more likely to stay during its life time than expected by chance. We applied this algorithm to the network of within animal movements made inside the State of Mato Grosso, for the year of 2007. This database holds information about 87,899 premises and 521,431 movements throughout the year, totalizing 15,844,779 animals moved. The community detection algorithm achieved a network partition that shows a clear geographical and commercial pattern, two crucial features to preventive veterinary medicine applications, and also has a meaningful interpretation in trade networks where links emerge from the choice of trader nodes