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41.
42.
Torres GJ Piquer FJ Algarra L de Frutos C Sobrino OJ 《Preventive veterinary medicine》2011,98(2-3):81-87
A cross-sectional study was conducted in Spain to estimate the prevalence of Salmonella enterica in feed mills and to identify and evaluate potential risk factors associated with feed contamination. A total of 3844 samples were collected from 523 different feed mills using a stratified sampling method. Samples were tested for the presence of Salmonella using conventional culture methods. When the presence of Salmonella was detected, samples were further characterised using serotyping at the National Reference Laboratory (NRL) for animal feed. Additional data about the biosecurity and hygiene measures, feed material used and compound feed produced, were collected by official veterinarians using a questionnaire in situ. In 144 of the feed mills visited (28%), Salmonella were present. However, it was only isolated from 4.8% of samples taken from all of the feed mills (3.5% from feed materials, 3.2% from compound feed and 12.5% from dust of the feed mill facilities). Salmonella serovars of public health importance (Enteritidis, Typhimurium, Infantis, Virchow and Hadar), were detected in only 2.7% of feed mills and in 0.3% of the samples studied. Logistic regression was used to investigate potential feed-mill risk factors for the isolation of Salmonella. Feed mill intake pits were demonstrated to have an increased risk of culture-positive dust samples (OR=6.4; 95% CI: 2.7-15.1). The feed material used in the production of compound feed was associated with recovery of Salmonella. Of the feed material used, cotton seeds were identified as having the highest odds of contamination (OR=3.8; 95% CI: 1.7-8.3). Pelleting appears to reduce the chance of contamination because non-pelleted compound feed is 8 times more likely to be contaminated than pelleted compound feed (OR=8.2; 95% CI: 2.5-26.6). The role of the feed itself in the epidemiology of Salmonella seems to be of limited importance as compound feed is not frequently contaminated at the feed mill level. This should not preclude Salmonella control measures from including all stages of feed production and they should have a risk-based approach according to the findings of this study. 相似文献
43.
Oscar Gonzalez-Fernandez Ignacio Queralt Maria Luisa Carvalho Gregorio Garcia 《Water, air, and soil pollution》2011,220(1-4):279-291
The distribution and mobility of heavy metals in the non-saturated zone of the alluvial plain of a wadi in the Cartagena–La Union mining district was investigated. The elemental chemistry of soils, in-depth sediments and different plant species (namely Hirsfeldia incana, Ditrichia viscosa and Piptatherum miliaceum) was carried out by using X-ray fluorescence and X-ray diffraction techniques. Potential mobility of metals was assessed by using lixiviation test runs (DIN 38414-S4). Concentrations detected in soils and sediments were higher than the acceptable limits reported in official regulations. Regarding metals mobility, values obtained for Pb, Zn and As exceed the limits established by European Union for DIN 38414-S4 leachates. Whilst the obtained leaching percentages for Pb, Cu and As were not especially high (<2%), Zn exhibit a very high leaching potential (up to 60% of the total metal content), involving potential risk of pollution events. 相似文献
44.
Seven hundred eighty male and female turkeys representing four genetic lines were challenged in four experiments with the Texas GB strain of Newcastle disease virus (NDV). The lines of turkeys included two randombred control lines (RBC1 and RBC2), a subline (E) of RBC1 selected for increased egg production, and a subline (F) of RBC2 selected for increased 16-week body weight. Mortality in turkeys of subline F (32.5%) was significantly higher than that in turkeys of line RBC2 (15.8%), subline E (17.5%), and line RBC1 (18.4%). At the end of each experiment, surviving birds were tested for antibody to NDV using the enzyme-linked immunosorbent assay (ELISA) and hemagglutination-inhibition (HI) test. Turkeys of subline E and line RBC1 had significantly lower ELISA antibody titers than those of subline F and line RBC2. Subline F had the highest HI antibody titers, followed in decreasing order by lines RBC2 and RBC1 and subline E. No apparent correlation was found between antibody response and mortality after NDV challenge. 相似文献
45.
Teixeira M Gil F Vazquez JM Cardoso L Arencibia A Ramirez-Zarzosa G Agut A 《Veterinary journal (London, England : 1997)》2007,174(1):133-138
The purpose of this study was to provide an atlas of the normal anatomy of the canine abdomen using helical computed tomographic (CT) images of the abdomen in four mature cross-breed dogs. The dogs were supported in sternal recumbency under general anaesthesia and scans were performed with 5 mm collimation and a pitch of 1. All sections were imaged with soft-tissue window settings and the cranial abdomen was also imaged with mediastinum-vascular window settings. CT scans were performed immediately after iodinated contrast medium was injected into the cephalic vein at 2 mL/kg. Iodinated contrast medium (10 mL/kg) was administered orally 2 h before the scan with a further 3 mL/kg administered immediately prior to scanning. A cross-sectional anatomy atlas was used to identify the structures of the abdominal cavity. Clinically relevant anatomical structures were identified and labelled in the CT images. 相似文献
46.
Gregorio Carozzi Alessandro Zotti Monica Alberti Federica Rossi 《Veterinary radiology & ultrasound》2015,56(6):628-637
Computed tomography (CT) is commonly used to investigate head tumors in dogs, however little information is available for lesions of the pharyngeal area. The purpose of this multicentric, retrospective, cross‐sectional study was to describe the CT findings in a sample of dogs with pathologically confirmed pharyngeal neoplasia and determine whether any CT features allowed differentiation of tumor type. Location of lesions, size and shape, margins, relationship with surrounding structures and vessels, attenuation characteristics and enhancement pattern, regional lymph node changes, and presence of metastasis were recorded by three observers (1 DECVDI). The effect of final diagnosis on each CT feature was tested. A total of 25 dogs were included: 15 with carcinomas, five sarcomas, four melanomas, and one lymphoma. The oropharynx and laryngopharynx were more frequently involved. Among tumor groups, lesions were of similar size, irregularly shaped, had ill‐defined margins, and had moderate‐to‐marked heterogeneous contrast enhancement. Lysis of hyoid bones was recorded in two carcinomas and infiltration of the lingual artery occurred in one case. Marked medial retropharyngeal lymphoadenomegaly was recorded in 11 of 14 carcinomas, in all sarcomas and in two of four melanomas. The single lymphoma case showed ill‐defined thickening of the oropharyngeal and laryngeal wall with retropharyngeal and mandibular lymphadenomegaly. Lung metastases were found in two of five sarcomas and two of four melanomas. Findings from the current study did not support the hypothesis that CT features could be used to predict pharyngeal tumor type in dogs. However, CT was helpful for determining mass extension, lymph node involvement, and distant metastatic spread. 相似文献
47.
Gentallan Renerio P. Bartolome Michael Cedric B. Cejalvo Reneliza D. Timog Emmanuel Bonifacio S. Altoveros Nestor C. Borromeo Teresita H. Endonela Leah E. 《Genetic Resources and Crop Evolution》2021,68(7):2767-2773
Genetic Resources and Crop Evolution - Combretum indicum (L.) DeFilipps seeds have anthelmintic properties and are recognized to be medicinal; however, the array of their morphological characters,... 相似文献
48.
Francisco García-Sánchez Pablo Botia Gregorio Fernández-Ballester Antonio Cerdá Vicente Martínez Lopez 《Journal of plant nutrition》2013,36(11):1933-1945
ABSTRACT Aspects of ammonium (NH4 +) toxicity in cucumber (Cucumis sativus L.) were investigated following growth with different N sources [nitrate (NO3 ?), NH4 +, or NH4NO3] supplied in concentrations of 1, 5, 10, or 15 mM. Plant dry weights and root: shoot ratios were lower with NH4 +-fed plants than with NO3 ?-fed plants. Ammonium accumulated strongly in leaves, stem, and roots when the concentration in the growth medium exceeded 1 mM. The increase in tissue NH4 + coincided with saturation of glutamine synthetase activity and accumulation of glutamine and arginine. Low tissue levels of calcium and magnesium in the NH4 +-fed plants constituted part of the NH4 +-toxicity syndrome. Additions of small amounts of NH4 + to NO3 ? -grown cucumber plants markedly increased the growth. 相似文献
49.
Dante L. Adorada B. J. Stodart C. Vera Cruz G. Gregorio I. Pangga G. J. Ash 《Euphytica》2013,192(1):1-16
Sheath lesions, grain sterility and grain discolouration of rice caused by Pseudomonas fuscovaginae can cause yield losses of up to 100 %. The most sustainable method of managing this disease is the use of host plant resistance. To identify sources of resistance an inoculation method that is practical, rapid and reliable is needed. We compare three different inoculation methods. Results showed that the pin-prick method is appropriate for identifying sources of resistance to P. fuscovaginae, while the spray method could be useful for mass screening of rice genotypes. The seed-soaking method was also evaluated and has showed potential in detection of early disease resistance. A total of 16 Multiparent Advanced Generation Inter-Crosses and 20 OryzaSNP set varieties from the International Rice Research Institute were evaluated using the pin-prick and seed-soaking methods. All growth stages were susceptible to the pathogen and the 107 cfu mL?1 inoculum concentration was optimal for discriminating between resistant and susceptible genotypes. For the pin-prick method, a single point assessment of disease severity at 14 days post-inoculation could be used instead of the AUDPC values to classify genotypes. An index of reduction in seedling height 10 days after seed soaking was established for the classification of the genotypes reaction to the disease. Resistant varieties identified using both the pin-prick and seed-soaking methods could be verified for use in disease resistance breeding programs. Of the 36 genotypes evaluated 22 were found to be resistant at the late booting or early panicle exsertion stage by pin-prick method, while 25 were resistant at the seed to germination stage. No correlation was found between the resistance classification of varieties between the two inoculation methods, indicating that there could be different mechanisms of resistance to P. fuscovaginae in rice. 相似文献
50.
Giovanni Vazquez‐Galindo Aline S. de Aluja Isabel Guerrero‐Legarreta Hector Orozco‐Gregorio Fernando Borderas‐Tordesillas Patricia Mora‐Medina Patricia Roldan‐Santiago Salvador Flores‐Peinado Daniel Mota‐Rojas 《Animal Science Journal》2013,84(4):350-358
This study assessed the effects of five different transport periods on physiometabolic responses and gas exchange in ostriches. It included 138 ostriches that were assigned to five experimental groups. G1 included 78 birds that were set aside as a reference group (RG). Each one of the four remaining experimental groups included 20 ostriches, which were transported in the following manner: G1 on one occasion for a period of 1 h; G2 on one occasion for 2 h; and G3 on one occasion for 3 h; G4a was made up of the ostriches from G1 but they were shipped on a second occasion, for 2 h (making a total of 3 h); finally, G4b was that same group, but after a third transport period, on this occasion during 3 h (for a total of 6 h). Groups G2 and G3 presented the most marked blood alterations (P < 0.05), including an increase in pH, hypocapnia (27.8 ± 0.80 mmHg), hypernatremia (171.75 ± 1.84 mmol/L), hypocalcemia (0.95 ± 0.03 mmol/L), and hyperglycemia (224.05 ± 3.94 mg/dL). Also, group G3 presented the lowest hematocrit values (26.5 ± 0.47 HTC%). Therefore, transporting ostriches with no prior experience for 3 h caused the most pronounced physiometabolic changes. 相似文献