Bioassays against pinewood nematode: assessment of a suitable dilution agent and screening for bioactive essential oils

Acetone was investigated and found to be an appropriate alternative to Triton X-100 as a solvent of essential oils in bioassays aimed to investigate their effects on pinewood nematode (Bursaphelenchus xylophilus) mortality. Therefore it was used as dilution agent to screen the effectiveness of fifty two essential oils against this pest. Thirteen essential oils were highly effective, resulting in more than 90% pinewood nematode mortality at 2 mg/mL, with six of them resulting in 100% mortality. LC100 values ranged between 0.50 mg/mL and 0.83 mg/mL for the essential oils of Origanum vulgare and Satureja montana, respectively. Essential oils were submitted to gas chromatography and gas chromatography-mass spectrometry analysis and their chemical composition established. Data from essential oils with 100% mortality at 2 mg/mL and other essential oils previously found to have LC100 ≤ 2 mg/mL was combined, their chemical profiles investigated by correspondences analysis plus automatic classification

Analytical solution of a plane strain pure bending problem in second gradient electroelasticity

Semi-inverse analytical solution of a pure bending problem for piezoelectric layer is developed in the framework of linear electroelasticity theory with strain gradient and electric field gradient effects. Two-dimensional solution is derived assuming plane strain state of a layer. It is shown that obtained solution can be used for the validation of size-dependent beam and plate models in second gradient electroelasticity theory

Epidemiological situation of bovine brucellosis in the State of Rondônia, Brazil

Realizou-se um estudo para caracterizar a situação epidemiológica da doença no Estado de Rondônia. O Estado foi estratificado em três circuitos produtores. Em cada circuito produtor foram amostradas aleatoriamente cerca de 300 propriedades e, dentro dessas, foi escolhido, de forma aleatória, um número pré-estabelecido de animais, dos quais foi obtida uma amostra de sangue. No total, foram amostrados 9.717 animais, provenientes de 927 propriedades. Em cada propriedade amostrada foi aplicado um questionário epidemiológico para verificar o tipo de exploração e as práticas zootécnicas e sanitárias que poderiam estar associadas ao risco de infecção pela doença. O protocolo de testes utilizado foi o da triagem com o teste do antígeno acidificado tamponado e o reteste dos positivos com o teste do 2-mercaptoetanol. O rebanho foi considerado positivo, se pelo menos um animal foi reagente às duas provas sorológicas. As prevalências de focos e de animais infectados do Estado foram de 35,2% [32,1-38,4%] e 6,2% [4,9-7,6%], respectivamente. Os resultados para os circuitos pecuários foram: circuito 1, 41,9% [36,3-47,6%] e 8,3% [5,9-10,8%]; circuito 2, 31,7% [26,5-37,2%] e 5,9% [4,3-7,6%]; circuito 3, 31,9% [26,7-37,4%] e 4,6% [2,5-6,6%]. Os fatores de risco (odds ratio, OR) associados à condição de foco foram: histórico de aborto (OR= 1,42 [1,04-1,95]) e exploração de corte (OR= 1,75 [1,30-2,38]). ______________________________________________________________________________________________________________ ABSTRACTA study to characterize the brucellosis epidemiological situation in the State of Rondônia was carried out. The State was divided into three regions. Three hundred herds were randomly sampled in each region. A pre-established number of animals were sampled in each of these herds. From 927 herds and 9,717 serum samples were collected. In each herd, it was applied an epidemiological questionnaire regarding herd features and also husbandry and sanitary practices that could be associated with risk of infection. The serum samples were screened for antibodies to Brucella spp. by the Rose-Bengal Test (RBT), and all RBT-positive sera were re-tested by the 2-mercaptoethanol test (2-ME). The herd was considered positive if at least one animal was positive on both RBT and 2-ME tests. The prevalences of infected herds and animals in Rondônia State were 35.2% [32.1-38.4%] and 6.2% [4.9-7.6%], respectively. In the regions, the prevalences of infected herds and animals were, respectively: region 1, 41.9% [36.3-47.6%] and 8.3% [5.9-10.8%]; region 2, 31.7% [26.5-37.2%] and 5.9% [4.3-7.6%]; and region 3, 31.9% [26.7-37.4%] and 4.6% [2.5-6.6%]. The risk factors (odds ratio, OR) associated with the presence of the infection were: recent history of abortion (OR= 1.42 [1.04-1.95]) and beef herd (OR=1.75 [1.30-2.38])

Epidemiologic situation of bovine brucellosis in the State of Mato Grosso, Brazil

Caracterizou-se a brucelose bovina em Mato Grosso por meio de um estudo transversal realizado em 2003 para auxiliar na implementação do Programa Nacional de Controle e Erradicação da Brucelose e Tuberculose. No Estado, estratificado em quatro circuitos pecuários, foram amostrados 13.684 animais, provenientes de 1.152 rebanhos. O protocolo de testes utilizado foi o da triagem com o teste do antígeno acidificado tamponado e os soros reagentes foram testados pelo 2-mercaptoetanol (ME) e concomitantemente retestados pelo teste de Rosa Bengala para resultado conclusivo. As prevalências de focos e de animais infectados foram: 41,2% [38,0-44,4%] e 10,2% [7,4-13,1%], respectivamente. Nos circuitos produtivos, as prevalências de focos foram 36,9% [29,2-45,2%], 27,2% [22,8-32,1%], 40,4% [38,8-46,2%] e 50,3% [44,5-56,1%]; e as prevalências de animais 7,9% [3,0-12,9%], 4,1% [2,8-5,4%], 8,1% [5,2-11,1%] e 15,3% [9,2-21,3%], respectivamente, para os circuitos 1, 2, 3 e 4. Os fatores de risco (odds ratio, OR) associados à condição de foco no Estado foram: exploração de gado de corte (OR= 1,8 [1,2-2,5]), exploração mista (OR=1,8 [1,2-2,7]), número de fêmeas no rebanho de 11 a 50 (OR=4,8 [1,1-20,8]), número de fêmeas no rebanho acima de 51 (OR=6,8 [1,6-29,0]), ocorrência de aborto (OR=1,7 [1,3-2,2]). A brucelose está homogeneamente distribuída no Estado, o que permite uniformidade de medidas sanitárias. Adicionalmente, sugere-se a intensificação da vacinação de fêmeas para todo o Estado. _______________________________________________________________________________________________________ ABSTRACTA study to characterize bovine brucellosis in the State of Mato Grosso was carried out in 2003 in order to support the implementation of the National Program for the Control and Eradication of Bovine Brucellosis. The State was divided into four productive regions, and 13,684 bovines from 1,152 herds were sampled. The serum samples were screened for antibodies to Brucella spp. by the Rose-Bengal test (RBT) and all RBT-positive sera were re-tested by the 2-mercaptoethanol test (2-ME), and again by RBT for confirmation. The prevalence of infected herds and animals in the State of Mato Grosso were 41.2% [38.0-44.4%] and 10.2% [7.4-13.1%], respectively. In the productive regions, the prevalence of infected herds were 36.9% [29.2-45.2%], 27.2% [22.8-32.1%], 40.4% [38.8-46.2%], and 50.3% [44.5-56.1%], respectively; and the prevalence of infected animals were 7.9% [3.0-12.9%], 4.1% [2.8-5.4%], 8.1% [5.2-11.1%], and 15.3% [9.2-21.3%], respectively, for regions 1, 2, 3, and 4. The risk factors (odds ratio, OR) associated with the presence of the infection in the State were: beef cattle farming (OR=1.8 [1.2-2.5]), mixed (beef and dairy) cattle farming (OR=1.8 [1.2-2.7]), farms with 11 to 50 females (OR=4.8 [1.1-20.8]), farms with more than 51 females (OR=6.8 [1.6-29.0]), and occurrence of abortion (OR=1.7 [1.3-2.2]). Given that brucellosis is homogeneously distributed in the State, uniform sanitary measures might be adopted. As a homogeneous additional measure for the State, the intensification of female vaccination is suggested

Epidemiological situation of bovine brucellosis in the State of São Paulo, Brazil

Realizou-se um estudo para caracterizar a situação epidemiológica da brucelose bovina no Estado de São Paulo. O Estado foi estratificado em sete circuitos produtores de bovinos, e 150 rebanhos com atividade reprodutiva foram aleatoriamente selecionados em cada um deles. No total, foram amostrados 1.073 rebanhos. Foram aletoriamente coletadas amostras de soro de 10 ou 15 fêmeas bovinas com idade ³24 meses, totalizando 8.761 animais. Os soros foram submetidos a um protocolo de testes em série, tendo o teste do antígeno acidificado tamponado como método de triagem e o da fixação de complemento como confirmatório. A prevalência estimada de rebanhos com pelo menos um animal soropositivo foi de 9,7% [7,8-11,6%], enquanto a prevalência estimada de animais soropositivos foi de 3,8% [0,7-6,9%], no Estado. Em cada rebanho foi aplicado um questionário epidemiológico para avaliar o grau de associação de possíveis fatores de risco (odds ratio, OR) com a doença. Propriedades com 87 ou mais bovinos (OR= 2,25) e compra de reprodutores (OR= 1,56) foram as variáveis mais associadas à condição de foco de brucelose. ____________________________________________________________________________________________________________ ARQUIVOA study to characterize the epidemiological situation of bovine brucellosis in the State of São Paulo was carried out. The state was stratified in seven cattle production regions and 150 herds with reproductive activity were randomly selected within each one. A total of 1,073 herds were sampled. In a second stage, 10 or 15 cows older than 24 month age (in herds with <100 cows and herds ≥100 cows, respectively) were bled at random. A total of 8,761 animals were bled. Sera were tested using a serial testing procedure with the Rose Bengal test as the screening method and the Complement Fixation as the confirmatory method. The estimated prevalence of herds with at least one positive animal was 9.7% [7.8-11.6%], whereas the estimated prevalence of positive cattle was 3.8% [0.7-6.9%] in São Paulo State. An epidemiological questionnaire was applied in each farm, allowing the evaluation of the association of selected risk factors with the disease. The characteristics associated with the brucellosis infected herds were farms with more than 87 bovines (OR= 2.25) and introduction of breeding cattle (OR= 1.56)