Garcia-Bocanegra I.,University of Cordoba, Spain |
Allepuz A.,Autonomous University of Barcelona |
Perez J.J.,Laboratorio Of Sanidad Y Produccion Animal |
Alba A.,Autonomous University of Barcelona |
And 6 more authors.
Veterinary Journal | Year: 2014
Six serological assays for the diagnosis of ovine brucellosis, due to Brucella melitensis were evaluated. Reference serum samples from sheep of known B. melitensis infection status (n= 118) were assessed using the Rose Bengal test (RBT), complement fixation test (CFT) and four commercial enzyme-linked immunosorbent assays (ELISAs), including two indirect ELISAs (iELISAs), one competitive ELISA (cELISA) and one blocking ELISA (bELISA).The highest differential positive rates (DPR) were obtained with the cELISA and bELISA, while the lowest DPR was estimated using iELISAs. A latent class analysis was performed to estimate the accuracy of the CFT, RBT and bELISA using 1827 sera from sheep undergoing testing as part of a surveillance and control programme. Lower sensitivity and specificity were obtained for the three serological tests when the field samples were used. A higher DPR was achieved by the CFT, compared to bELISA and RBT. The results suggest that ELISAs, and particularly the bELISA, might be suitable for inclusion in the European Union legislation on intra-community trade for diagnosing B. melitensis infection in sheep, as it has a similar test performance compared to the RBT. © 2013 Elsevier Ltd.
Gonzalez-Dugo M.P.,IFAPA Centro del Llano |
Escuin S.,Agencia de Gestion Agraria y Pesquera de Andalucia AGAPA |
Cano F.,Agencia de Gestion Agraria y Pesquera de Andalucia AGAPA |
Cifuentes V.,Confederacion Hidrografica del Guadalquivir |
And 5 more authors.
Agricultural Water Management | Year: 2013
Water management at different decision levels may be supported by the assessment of evapotranspiration (ET) on large spatial scales. In this study, a previously validated approach to estimating unstressed ET, based on the ability of vegetation indices to trace crop growth and thus to derive basal crop coefficients, has been applied to the irrigated areas of the Guadalquivir river basin in southern Spain. Vegetation indices, provided by a series of high spatial resolution satellite images for 2007, 2008 and 2009, supported the assessment of daily to seasonal ET of individual fields, enabling crop-oriented and individual water use to be analysed. The segmentation of the basin into zones with homogeneous climate and crop-growth patterns was the first step towards crop identification based on temporal trends in the Soil-Adjusted Vegetation Index (SAVI). Non-permanent crops were classified with good accuracy. Existing spatial databases of permanent crops enabled land use to be determined. The applied methodology has been compiled in a planning and operational tool named MINARET (MonitorINg irrigated AgricultuRe ET) for routinely monitoring crop water consumption in the irrigated lands of the Guadalquivir basin and it is now available for the Guadalquivir river authority. © 2013 Elsevier B.V. All rights reserved.