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The aim of this study was to define the differences between the Brazilian states that export and do not export meat to the European Union (EU) and to identify the variables that are important to meet the export requirements. Infrastructure and computerization of the control of animal transit in Brazil that impact on regional health status were evaluated and linked to other variables such as status for foot and mouth disease (FMD) and qualification to export meat to EU. Variables related to transit control of bovines implemented by the state agencies of animal health and inspection in each Brazilian state were evaluated. Using a discriminant analysis, four variables were selected that explained the variation between Brazilian states that were “free” and “not free” of FMD while another four were selected to explain the variation between the zones “approved” and “not approved” to export meat to the EU, including number of official veterinarians, total transit of bovines and buffaloes, total number of animal transit certificates issued for bovine and buffaloes at the state or zone level, and total number of municipalities in the state or zone. It was possible to correctly discriminate between “free” and “not free” FMD states or zones. Variables related to animal transit are important in assessing the state for the classification of animal health situation and for EU approval for the exportation of meat.  相似文献   
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An outbreak of human leishmaniosis was confirmed in the southwest of the province of Madrid, Spain, between July 2009 and December 2012. Incidence of Leishmania infection in dogs was unchanged in this period, prompting a search for alternative sylvatic infection reservoirs. We evaluated exposure to Leishmania in serum samples from animals in the area with an indirect immunofluorescence test (IFAT). Using promastigotes from six culture passages and a 1/25 threshold titer, we found anti-Leishmania infantum seroreactivity in 9.3% of cats (4 of 43), 45.7% of rabbits (16/35) and 74.1% of hares (63/85). Use of promastigotes from >10 in vitro passages resulted in a notably IFAT lower titer, suggesting antigenic changes during extended culture. Postmortem inspection of seropositive animals showed no clinical signs of infection. The results clearly suggest that asymptomatic hares were the main reservoir in the outbreak, and corroborate IFAT as a sensitive serological surveillance method to detect such cryptic Leishmania infections.  相似文献   
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Leptospirosis is a zoonotic disease that occurs in humans and several animal species, including cattle, pigs, and horses, and it has a worldwide distribution. In equids, leptospirosis manifests through recurrent uveitis and abortion and other reproductive disorders. The objective of the present study was to investigate the epidemiological situation of Leptospira spp. infection in equids from the Brejo Paraibano microregion in the northeast of Brazil, that is, to assess the prevalence of and identify the major risk factors for infection. For this purpose, blood samples were taken from 257 equids (204 horses, 46 mules, and 7 donkeys), and a microscopic agglutination test (MAT) was used as serological analysis, with 24 serovars of Leptospira spp. as antigens. Antibodies were observed in 16.2% of horses, 13.0% of mules, and 28.6% of donkeys. Animals between the ages of 2.5 and 11 years had a risk of infection 0.4 times lower than those younger than 2.5 years old (odds ratio, 0.4; 95% confidence interval, 0.18-0.90). Further studies are needed to identify potential wild reservoirs and the main routes of infections.  相似文献   
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This study was aimed at describing post-fire mushroom production in a Mediterranean ecosystem dominated by Pinus pinaster Ait. in the northwest of Spain and assessing the results by classificatory models. During the autumn periods of 2003–2006, fruit bodies from 115 fungal taxa were collected in burned and unburned areas and were further grouped into the following categories: saprotrophic/mycorrhizal; and edible/non-edible. After wildfires, a significant reduction in the number of fungal species and fruit body biomass production was observed. Based on this relevant information, the first simple classificatory model for this aim is provided. Nine alternative models based on classifications according to combinations of edibility and functional groups were fitted, and four fruiting body biomass production classes were defined as possible responses. As explanatory factors, time after fire and climatic variables significantly related to fruit body production were included. The best predictive results were obtained for edible and edible-mycorrhizal models, for which the correct classification rate of production classes was between 92 and 85 %. Moreover, the models obtained were applied to analyse the effect of time after fire on fungal production. Mycorrhizal and edible fungal production after fire was classified into the lowest class, whereas saprotrophic and non-edible species followed a contrary trend. The classificatory models can be useful to optimise management and harvest of these increasingly appreciated non-timber forest resources.  相似文献   
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Shrimp aquaculture is an important industry that experiences significant losses from Vibrio species, especially at the larval and juvenile stages. Proteinaceous virulence factors, including alkaline proteases, metalloproteases, cysteine proteases and alkaline serine proteases, have been identified as important elements in Vibrio pathogenesis. This review summarizes current knowledge regarding the principal pathogenic Vibrio species in shrimp, with emphasis on relevant exotoxins and their modes of action, principal characteristics and molecular database. This pathogenic factors and their relation with other molecules produced by microorganisms may be help to understand the virulence mechanisms present in Vibrio strain.  相似文献   
27.
Nine commercial feeding attractants and stimulants for Litopenaeus vannamei were evaluated by observation of behavioral responses in animals allotted in one Y-maze aquarium apparatus. In the validation phase, fishmeal–Brazilian origin (FMBO); fishmeal–Peruvian origin (FMPO); blood meal (BM), meat and bone meal (MBM), squid meal (SM), fish oil (FO) and fish solubles (FS) were evaluated. There was also a control without stimulatory raw material. The tested materials were included at 3% in neutral gelatin pellets (wet basis). In each behavioral observation, two different ingredients were offered at the same time in equal quantities, being allotted in the end of each chamber's arm. In Phase II after system validation, the following commercial attractants were tested: 80% crude protein (CP) vegetable dried biomass (VDB80), 68% CP vegetable dried biomass + glutamate + betaine (VDB68), complex of amino acids (alanine, valine, glycine, proline, serine, histidine, glutamic acid, tyrosine and betaine) with enzymatically digested bivalve mollusk (CAA), condensed fish soluble protein (CFSP), squid liver meal (SLM), betaine (Bet), dried fish solubles–low biogenic amines (DFSLB), dried fish solubles–high biogenic amines (DFSHB) and whole squid protein hydrolysate (WSPH). Attractants were used at a 3% level wet basis with neutral gelatin, without any additional ingredient source available. The best four commercial attractants from this phase (CAA, CFSP, SLM and WSPH) were compared under 0.5% and 1.0% levels. In Phase I of the study, a higher percentage of choices were observed for FMPO and FMBO. BM and FO were the least chosen ingredients. In Phase II, the worst results were observed for Bet, DFSHB and, mainly, for VDB80 and VDB68. When two-by-two comparisons were performed, results suggested that CFSP and CAA were the best commercial attractants tested. In the last phase, both CFSP and CAA at 1.0% level were significantly more chosen by shrimp than CFSP (0.5%), SLM (0.5 or 1.0%) or WSPH (0.5 or 1.0%). At both 0.5% and 1.0% levels, shrimp spent a similar amount of time feeding on CFSP and CAA. However, only CAA was statistically better than SLM and WSPH together. Further work is required to better elucidate the chemical drivers of chemostimulation for L. vannamei for each one of the attractants tested.  相似文献   
28.
Diverse actinomycetes produce a family of structurally and biosynthetically related non-ribosomal peptide compounds which belong to the chromodepsipeptide family. These compounds act as bisintercalators into the DNA helix. They give rise to antitumor, antiparasitic, antibacterial and antiviral bioactivities. These compounds show a high degree of conserved modularity (chromophores, number and type of amino acids). This modularity and their high sequence similarities at the genetic level imply a common biosynthetic origin for these pathways. Here, we describe insights about rules governing this modular biosynthesis, taking advantage of the fact that nowadays five of these gene clusters have been made public (thiocoraline, triostin, SW-163 and echinomycin/quinomycin). This modularity has potential application for designing and producing novel genetic engineered derivatives, as well as for developing new chemical synthesis strategies. These would facilitate their clinical development.  相似文献   
29.
Neospora caninum is a protozoon that causes abortion in cattle and neuromuscular lesions in dogs, with the formation of cysts mainly in the central nervous system. Since N. caninum is an intracellular parasite with tropism for the cells of nervous system, this study evaluated the respiratory metabolism of glial cells infected by this* parasite. Glial cultures obtained from the cerebral cortex of newborn rats were kept in DMEM enriched with 10% fetal bovine serum, 1 mM pyruvic acid and 2 mM of L-glutamine. They were infected at a ratio of approximately 1:1 (cell/parasite). Oxygen consumption was evaluated by polarography in the non infected and N. caninum infected groups, 24 and 72 h following infection. Glial cell respiration after 24 and 72 h was 307.2 +/- 34.7 and 308.9 +/- 64.1 microL of oxygen per mug of total protein per minute, and 566.2 +/- 54.6 and 579 +/- 117.5 microL O2/microg of total protein/minute in the control and infected groups, respectively. These results show that N. caninum does not interfere with glial respiration in vitro.  相似文献   
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