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101.
Deltamethrin (DM) is a pyrethroid insecticide widely used in Brazilian crops and in pest-control programs because of its low environmental persistence and toxicity. It has been shown to exert a wide range of effects on non-targeted organisms including fishes. The aim of this study to evaluate the effects of deltamethrin through the hematological and biochemical parameters using Ancistrus multispinis as animal model. First, blood of A. multispinis was collected by cardiac puncture in order to evaluate the basal values of the total cell counts, hemoglobin and hematocrit rates. A. multispinis showed low number leukocytes, red blood cells and hemoglobin compared to other species. The intoxication with DM (0.1 or 0.3 mg kg−1) induced leukocytosis and increases the number of erythrocytes and hemoglobin levels 96 h after the injection when compared to vehicle-injected animals. The injection of lipopolysaccharide (LPS) also induced a significant leukocytosis and increased the erythrocytes number 4 h after the injection. The combination of the higher dose of DM with LPS showed an additional effect in the number of leukocytes and erythrocytes. The GST and EROD activities were also evaluated in the gills and liver, respectively, 96 h after intoxication with both doses of DM. The GST activity decreased after DM intoxication in both doses while EROD activity was not significantly different. These results suggest that A. multispinis is a valuable model for ecotoxicological studies. Also, DM can affect the metabolizing system (GST) and immunologic system of A. multispinis, a condition that can be worsened in the presence of inflammation or infection.  相似文献   
102.
The grapevine plays a very important role in the economic, social and cultural sectors of many regions; however vineyards are often grown in regions under stressful conditions and thus they are vulnerable to climate change. The objective of this research was to investigate the effect of partial root-zone drying (PRD) irrigation on vine water relations, vegetative growth, plant microclimate, berry composition and yield components, compared to conventional deficit irrigation (DI, 50% ETc), full irrigation (FI, 100% of ETc) and non-irrigated vines (NI). The study was undertaken in mature ‘Moscatel’ grapevines (Vitis vinifera L.) grown in Pegões, South of Portugal. Compared to the other irrigated treatments, PRD vines showed a better microclimate at the cluster zone with higher incident photosynthetic photon flux density (PPFD). Within the more open canopies of NI and PRD treatments, berry temperatures were higher than those of denser ones (DI and FI). Compared to the conventional irrigation technique the better microclimate observed in PRD vines was a consequence of a reduction in vine growth, where lower values of leaf layer number, leaf area, canopy wideness, water shoots and shoot weight were observed. In PRD vines we observed a tendency to a development of a deeper root system, while DI and FI showed a more homogeneous root distribution throughout the different soil layers. PRD showed an improvement in berry quality with higher values of flavour precursors, and total phenols concentration without any significant yield reduction compared to DI and FI.  相似文献   
103.
Zucchini lethal chlorosis virus (ZLCV) is a tospovirus that infects species of cucurbits in Brazil and is transmitted by the thrips Frankliniella zucchini. The purpose of the present work was to evaluate the reaction of seven species of cucurbits to infection with ZLCV under field and greenhouse conditions in Piracicaba County, SP. In the field experiment, ZLCV infection occurred naturally. In the greenhouse, plants were mechanically inoculated with ZLCV at the cotyledonal stage. Evaluations were based on symptoms expression and detection of the virus by PTA-ELISA. The percentages of infected plants for field and greenhouse assays, respectively, are indicated in parenthesis for each species/cultivar: Cucurbita pepo var. Caserta (72.9 and 70.7); C. maxima var. Alice (16.0 and 10.4); C. maxima var. Exposição (0.0 and 0.0); C. moschata var. Menina Brasileira (29.2 and 18.2); C. maxima × C. moschata hybrid Takaiama (63.4 and 42.7); Citrullus lanatus var. Crimson Sweet (25.0 and 25.0); Cucumis sativus var. Safira (14.3 and 41.2); and C. anguria (21.4 and 22.7).  相似文献   
104.
Resistance to the dicotyledenous parasite Orobanche cumana in sunflower is characterized by a low number of parasitic attachments and a confinement of the parasite in host tissues leading to its necrosis. To help understand what determines such resistance mechanisms, molecular, biochemical and histological approaches were employed before (early response) and after (late response) attachment of the broomrape parasite to susceptible (2603) and resistant (LR1) sunflower genotypes. The expression patterns of 11 defence-related genes known to be involved in different metabolic pathways (phenylpropanoids, jasmonate, ethylene) and/or in resistance mechanisms against microorganisms were investigated. RT-PCR and cDNA blot experiments revealed that the resistant genotype exhibited a stronger overall defence response against O. cumana than the susceptible one, involving marker genes of the jasmonate (JA) and salicylic acid (SA) pathways. Among them, the SA-responsive gene, def. (defensin), appeared to be characteristic of LR1 sunflower resistance. However, no JA accumulation and similar SA contents (250–300 ng g−1 FW) were measured by GC/MS in both genotypes, parasitized or not. In addition, three cDNAs, isolated by a suppression-subtractive hybridization, were shown to be strongly induced only in the resistant genotype 8 days post-inoculation, when the first O. cumana attachments occurred. These genes, putatively encoding a methionine synthase, a glutathione S-transferase and a quinone oxidoreductase, might be involved in detoxification of reactive oxygen species, suggesting the occurrence of an oxidative burst during the incompatible interaction. Finally, host cell-wall modifications leading to parasite-confinement were correlated with more intense callose depositions in the resistant genotype, concomitant with over-expression of the callose synthase cDNA HaGSL1 .  相似文献   
105.
The plant pathogenic fungus Corynespora cassiicola causes a severe leaf spot disease on more than 70 host plant species including Hevea brasiliensis . Genetic variability in 32 isolates of C. cassiicola collected from diverse hosts and locations in Sri Lanka and Australia was assessed using restriction fragment length polymorphism (RFLP) analysis of the internal transcribed spacer (ITS) region of ribosomal DNA and random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) analysis of total fungal DNA. Amplified ITS fragments from all 32 C. cassiicola isolates exhibited an identical size, and restriction analysis with seven different restriction endonucleases revealed identity in all of the detected DNA fragments. This finding of high genetic relatedness was further supported by the cloning and DNA sequencing of the ITS2 region from one Sri Lankan and one Australian isolate. However, RAPD-PCR profiles generated by 15 oligonucleotide decamer primers revealed significant polymorphism between groups of organisms. Genetic relationships among the isolates were determined by cluster analysis of the RAPD-PCR data and seven different RAPD groups were identified. Isolates showed strong correlations between the assigned RAPD group and the location and host plant genotype from which the isolate was collected. Correlations were also observed between the RAPD group, growth of the isolate and pathogenicity on different plant hosts.  相似文献   
106.
Microbial isolates from living petals, petal residues and leaf residues of rose, and from laboratory collections, were evaluated for control ofBotrytis cinerea in rose. In leaf residues artificially infested withB. cinerea, isolates of the filamentous fungiGliocladium roseum, FR136 (unidentified) andTrichoderma inhamatum reduced sporulation of the pathogen by >90%, other filamentous fungi were 25–90% effective, and those of yeasts and bacteria were <50% effective. In artificially inoculated petal residues, no microbe reduced sporulation ofB. cinerea by >75%, but isolates ofCladosporium oxysporum and four yeasts were 51–75% effective, and three filamentous fungi, eight yeasts andBacillus subtilis isolates were 26–50% effective. Isolates ofT. inhamatum, C. oxysporum andG. roseum performed best againstB. cinerea among isolates evaluated in leaf residues naturally infested with the pathogen and indigenous microorganisms. Totals of ten isolates of filamentous fungi (includingC. oxysporum andC. cladosporioides), two of yeasts and five ofBacillus subtilis completely prevented lesion production byB. cinerea in detached petals, and a further six isolates of filamentous fungi (includingG. roseum) and six yeasts were 90–99% effective. Isolates ofC. oxysporum, C. cladosporioides andB. subtilis, the most effective microorganisms againstB. cinerea in flower buds, reduced number of lesions in the range of 42–65% compared with 59–89% for à standard fungicide (vinclozolin). It is suggested that application of leading antagonists Jo living rose leaves and flowers should optimize control of inoculum production byB. cinerea when the tissues die. Optimal biocontrol of lesion production in flower buds requires a better understanding of the microenvironment of petals.  相似文献   
107.
Objective To evaluate standing, percutaneous, ultrasound-guided, transthoracic liver biopsy in mares, and transabdominal, laparoscopically-guided, liver biopsy under general anaesthesia in foals, as techniques for obtaining tissue for assessment of copper status. The techniques were evaluated with respect to ease of use and effect on the animal.
Procedure Twenty of 24 Thoroughbred mares and 21 of their foals were biopsied. The animals were part of a larger study of the effect of copper supplementation on copper status and the prevalence of developmental orthopaedic disease. Livers were also collected from unrelated horses and sampled to investigate the variability in the distribution of copper in liver tissue.
Result The biopsy technique caused no lasting effect on the mares, but there was an increased risk of viscus penetration associated with taking multiple biopsy cores. The use of ultrasonography to scan the target area for the liver identified four cases that were not appropriate candidates for liver biopsy, because of large intestine being located in the biopsy area. In the foals there were no serious postoperative adverse effects, nor was there any evidence of problems caused by the procedure when the abdomen was examined post-mortem at 5 months of age. In livers collected to investigate the variability of copper concentration, copper appeared to be relatively evenly distributed through the liver.
Conclusion Standing, percutaneous, ultrasound-guided, transthoracic liver biopsy in mares, and transabdominal, laparoscopically-guided, liver biopsy under general anaesthesia in foals are convenient procedures for obtaining liver tissue for assessing copper status in horses. The use of ultrasound to identify liver tissue is recommended, especially in older mares.  相似文献   
108.
Veterinary Research Communications - Propofol is a widely used drug in veterinary medicine to induce anesthesia; as well as the chosen compound for protocols of intravenous anesthesia. The present...  相似文献   
109.
Veterinary Research Communications - This study aimed to describe the transmission of T. gondii in naturally infected goats in the semiarid region of northeastern Brazil, through evaluating the...  相似文献   
110.
The antibacterial effects of extracts obtained from Persea cordata stem bark, employed in Brazil to treat infectious diseases, were studied. The ethyl acetate fraction of the hydroalcoholic extract showed activity against pathogenic bacteria which may justify the popular use of the plant.  相似文献   
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