13 research outputs found
Prediction of apparent digestibility of hays from natural pastures of the Northeast region of Portugal
In the Northeast region of Portugal hays from natural pastures are traditionally used as the main feed during the period of drought and the evaluation of its nutritive value is essential. The aim of this study was to predict the apparent organic matter digestibility (OMD) of 21 hays from natural pastures based on chemical composition, pepsin-cellulase solubility of organic matter (OMS) and in vitro organic matter digestibility.
Chemical composition of hays showed a wide range of values and acid detergent lignin (ADL) was the component that presented the highest variation (CV = 18.4%). The OMD varied between 516 and 658 g/kg OM. The best single OMD predictor was OMS (RSD = 2.8%, R2 = 0.52, P<0.001). Using multiple regression to predict OMD, the variables included in the model were OMS and ADL (OMD = 21.51 + 0.94 OMS – 0.83 ADL; RSD = 2.75%; R2 = 0.54; P<0.0001). According to principal component analysis (PCA) hays were divided in 3 groups and the multiple regression established for the larger group of hays (n=10) was: OMD = 4.13 + 0.85 OMS – 1.03 ADL; RSD = 2.13%, R2 = 0.77, P<0.0001.
The OMS method was superior to chemical composition and to the in vitro rumen fluid method in predicting OMD of hays from natural pastures. Results from PCA suggested that it may be useful to group these hays according to its chemical composition to accurately predict OMD
Molecular identification of Rickettsia felis in ticks and fleas from an endemic area for Brazilian Spotted Fever
Rickettsioses are arthropod-borne diseases caused by parasites from the
Order Rickettsiales. The most prevalent rickettsial disease in Brazil
is Brazilian Spotted Fever (BSF). This work intends the molecular
detection of those agents in ectoparasites from an endemic area of BSF
in the state of Espírito Santo. A total of 502 ectoparasites,
among them Amblyomma cajennense , Amblyomma σdubitatum (A.
cooperi), Riphicephalus sanguineus , Anocentor nitens and
Ctenocephalides felis , was collected from domestic animals and the
environment and separated in 152 lots according to the origin.
Rickettsia sp. was detected in pools of all collected species by
amplification of 17kDa protein-encoding gene fragments. The products of
PCR amplification of three samples were sequenced, and Rickettsia felis
was identified in R. sanguineus and C. felis. These results confirm the
presence of Rickettsia felis in areas previously known as endemic for
BSF, disease caused by Rickettsia rickettsii. Moreover, they show the
needing of further studies for deeper knowledge of R. felis-spotted
fever epidemiology and differentiation of these diseases in Brazil
Molecular detection of Ehrlichia canis in cats in Brazil
Submitted by Alvaro Nogueira ([email protected]) on 2017-11-29T09:50:32Z
No. of bitstreams: 1
1-s2.0-S1198743X14634777-main.pdf: 51036 bytes, checksum: cec8133f84d53d19eb52a5749ab7138b (MD5)Approved for entry into archive by Nathália Faria da Silva ([email protected]) on 2017-11-29T09:52:02Z (GMT) No. of bitstreams: 1
1-s2.0-S1198743X14634777-main.pdf: 51036 bytes, checksum: cec8133f84d53d19eb52a5749ab7138b (MD5)Made available in DSpace on 2017-11-29T09:52:02Z (GMT). No. of bitstreams: 1
1-s2.0-S1198743X14634777-main.pdf: 51036 bytes, checksum: cec8133f84d53d19eb52a5749ab7138b (MD5)
Previous issue date: 2009-1
Rickettsial spotted fever in capoeirão Village, Itabira, Minas Gerais, Brazil Rickettsiose do grupo da febre maculosa na Vila de Capoeirão, Itabira, Minas Gerais, Brasil
The present study investigated the infection by spotted fever rickettsia in an endemic area for Brazilian spotted fever (BSF; caused by Rickettsia rickettsii) in Minas Gerais State, Brazil. Human, canine and equine sera samples, and Amblyomma cajennense adult ticks collected in a rural area of Itabira City, Minas Gerais State were tested for rickettsial infection. Through Immunofluorescence Assay (IFA) we demonstrated the presence of antibodies anti-R. rickettsii in 8.2%, 81.3% and 100% of the human, canine and equine sera, respectively. None of the 356 tick specimens analyzed were positive for Rickettsia by the hemolymph test or Polymerase Chain Reaction technique (PCR) for the htrA and the gltA genes. Our serological results on horses and dogs (sentinels for BSF) appoint for the circulation of a SFG Rickettsia in the study area, however in a very low infection rate among the A. cajennense tick population.<br>O presente estudo investigou a infecção por rickéttsias do grupo da febre maculosa (GFM) em área endêmica para febre maculosa brasileira (FMB; causada por Rickettsia rickettsii) no Estado de Minas Gerais, Brasil. Amostras de soros de humanos, cães e eqüídeos, e carrapatos Amblyomma cajennense adultos colhidos em um povoado rural em Itabira, Minas Gerais foram testados para infecção por Rickettsia. Pela Reação de Imunofluorescência Indireta (RIFI) foram detectados anticorpos anti-R. rickettsii em 8,2% dos soros humanos, 81,3% dos cães e em 100% dos eqüídeos. Nenhum dos 356 carrapatos se mostrou positivo para Rickettsia no teste de hemolinfa e na reação em cadeia pela polimerase (PCR) objetivando amplificar fragmentos de DNA dos genes htrA and the gltA. Os resultados sorológicos em eqüinos e cães (sentinelas para FMB) apontam para a circulação de uma rickéttsia do GFM na área do estudo, porém, numa freqüência de infecção muito baixa na população do carrapato A. cajennense
Seleção recorrente recíproca na obtenção de híbridos interpopulacionais de milho-pipoca Reciprocal recurrent selection to obtain interpopulation hybrids of popcorn
O objetivo deste trabalho foi avaliar a eficiência da seleção recorrente recíproca em produzir híbridos de milho-pipoca (Zea mays) de progênies endógamas superiores, com famílias de irmãos-completos. O programa de seleção recorrente recíproca envolveu as populações de milho-pipoca 'Viçosa' e 'Beija-Flor'. Os testes dos híbridos S0xS0 e S1xS1 foram conduzidos em delineamento látice, nos anos agrícolas de 2002/2003 e 2004/2005. Os dois ensaios incluíram testemunhas comerciais comuns, que permitiram a comparação do desempenho dos híbridos. Analisaram-se a produtividade e a capacidade de expansão. Foram preditos ganhos direto e indireto com a seleção em capacidadede expansão, avaliada em pipoqueira de ar quente e na pipocadora "Metric Weight Volume Tester". Os ganhos observados foram calculados para avaliar a eficiência da seleção recorrente recíproca. As análises de covariância mostraram variabilidade genotípica nas populações. Em relação às testemunhas comerciais, os híbridos S0xS0 foram inferiores em qualidade e equivalentes em produtividade, e os híbridos S1xS1 foram equivalentes nas duas características. O ganho observado na capacidade de expansão foi substancial, cerca de 4 mL g-1, superior ao ganho predito (2,8 mL g-1). A redução observada na produtividade não foi relevante. Verificou-se redução na variabilidade genotípica quanto à capacidade de expansão. O método de seleção recorrente recíproca foi eficiente em produzir híbridos S1xS1 superiores aos S0xS0.<br>The objective of this work was to evaluate the efficiency of reciprocal recurrent selection in producing hybrids of popcorn (Zea mays) from superior endogamous progenies, with full-sibling families. The reciprocal recurrent selection program involved the 'Viçosa' and 'Beija-Flor' popcorn populations. Tests of the hybrids S0xS0 and S1xS1 were carried out in lattice design, in the agricultural years 2002/2003 and 2004/2005. The two assays included common commercial controls, allowing for the comparison of the hybrids performance. Productivity and expansion capacity were evaluated. Direct and indirect gains with selection were predicted on expansion capacity assessed in hot air and Metric Weight Volume Tester popcorn makers. The gains observed were calculated to evaluate the efficiency of the reciprocal recurrent selection. The covariance analyses showed genotypic variability in the populations. When compared to the commercial controls, the S0xS0 hybrids were inferior in quality and equivalent in productivity; and the S1xS1 hybrids were equivalent in both traits. The observed gain in expansion capacity was substantial (around 4 mL g-1) and higher than the predicted gain (2.8 mL g-1). The reduction observed in productivity was not relevant. Reduction in the genotypic variability was verified for expansion capacity. The reciprocal recurrent selection method was efficient in producing S1xS1 hybrids superior to S0xS0 hybrids