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1.
A total of 45 non-uremic dogs, with clinical signs indicating leishmaniosis, entered the study. Diagnosis was confirmed by indirect immunofluorescence assay (IFA) on serum and polymerase chain reaction (PCR) on bone marrow samples. The dogs were randomly allocated into Group A (n=37) that received allopurinol (10mg/kg B.W., per os, twice daily) for 4 consecutive months, and Group B (n=8) that were placebo-treated. Clinical signs were scored just before and at monthly intervals throughout the study period, in a blinded and independent fashion. Complete blood count, serum biochemistry profile, urinalysis, lymph node and bone marrow parasitology, IFA and enzyme-linked immunosorbent assay (ELISA) serology and bone marrow PCR were carried out at the beginning and at the end of the trial. A total of three Group A and one Group B dogs died of end stage kidney disease that developed during the trial. In Group A animals that endured the trial there was a significant improvement in the general body condition, conjunctivitis, peripheral lymphadenopathy, splenomegaly, masticatory muscle atrophy, ulcerative stomatitis, epistaxis, exfoliative dermatitis, cutaneous ulcerations, blepharitis and nasodigital hyperkeratosis. The same observation was made for anemia, lymphopenia, hyperproteinemia, hyperglobulinemia, hyperphosphatemia, increased alkaline phosphatase activity and the low albumin/globulin ratio. By contrast, no improvement of any kind was seen in Group B dogs. Lymph node and bone marrow parasite numbers were significantly decreased in Group A animals. In Group B, that occurred only in the lymph nodes. Apart from remission of clinical signs and restoration to normal of clinicopathological abnormalities, allopurinol did not eliminate Leishmania organisms, as the PCR result on bone marrow was still positive in all the dogs that finished the trial.  相似文献   
2.
The sorption data for Corsican pine wood chemically modified with a homologous series of linear chain carboxylic acid anhydrides was analysed using various models, namely, BET, Dent, Le and Ly, Hailwood and Horrobin, Nelson, and Henderson. Hailwood and Horrobin resulted in the more appropriate model to represent the equilibrium data of chemically modified wood. In the present study, the parameter representing the molecular weight of the dry cell wall in the Hailwood and Horrobin isotherm was perfectly correlated with the weight percentage gain of anhydride. A linear relation was proposed between these two parameters in order to fit all experimental isotherms (the results showed an r2=0.993).  相似文献   
3.

Silvopastoral systems integrate the complexity of forestry and forage-livestock management in an economically and ecologically sustainable way. However, these systems have undergone intensive pressure over the past decades caused by changes in land uses, as well as, in local socioeconomic priorities that suppressed traditional practices such as livestock grazing. These changes have caused land cover spatiotemporal diversifications whose effects were investigated in a traditional oak silvopastoral system at western Greece. In order to investigate the effect of human activities over the study area, the spatiotemporal land cover changes in conjunction with human and animal population changes and the environmental factors altitude, soil depth, inclination and rock type were analyzed. Also, forest-crown density changes were examined as a complimentary factor for the investigation of human intervention in the study area. Data about land-cover changes were derived from aerial orthorectified photographs of years 1945 and 2008, complimented by maps of environmental factors. Data digitization was implemented by the use of ArcGis. Based on the data analysis it derives that land cover changes are mainly attributed to direct human intervention. Environmental factors affect the ecosystem in two ways; first by affecting the location, type and intensity of human activities in the area, for example, soil depth determines where land is more productive and so predetermines the location, type and intensity of agricultural activities. Secondly, in the areas without or with minimal human intervention, environmental factors affect directly the land cover in conjunction with natural species necessities and their antagonistic capabilities.

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4.
During March 2013, we investigated the presence and the levels of Schmallenberg virus (SBV) circulation in three dairy cow herds and three sheep flocks in Central Macedonia, Greece. In two cow herds, a high number of abortions had been observed during the winter. Six bulk-tank milk samples and 147 individual sera were screened for SBV-specific antibodies by ELISA. Positive reactions were obtained from 5 out of 6 bulk-tank milk samples, 58 out of 90 sera from the 3 cow herds, and 2 sera from 2 of the 3 sheep flocks. Twenty-two ELISA-positive sera were tested by serum neutralization test (SNT). SNT confirmed the presence of neutralizing antibodies against SBV in all samples tested, with titers ranging between 1:32 and ≥1:256. No neutralizing antibodies against Akabane virus (AKAV) or Shamonda virus (SHAV) were detected, indicating that neutralizing antibodies against SBV do not cross react with AKAV or SHAV in SNT. ELISA testing of bulk-tank milk samples proved to be convenient and reliable. None of the tested sera was found positive for SBV by real-time RT-PCR, indicating that the sampling was conducted past the viremia stage. This is the first report of SBV circulation in Greece.  相似文献   
5.
Atlantic sturgeon (Acipenser oxyrhynchus), which are bottom dwelling and migratory fish, experience environmental hypoxia in their natural environment. Atlantic sturgeon, acclimated to either 5 or 15°C, were subjected to a 1 h severe (<10 mm Hg) hypoxia challenge in order to document their physiological responses. We measured hematological parameters, including O2 transport (hemoglobin, hematocrit), ionic (chloride, osmolality), and metabolic (glucose, lactate) variables under normoxic conditions (~160 mm Hg), immediately following a 1 h exposure to hypoxic water, and following a further 2 h of recovery from this challenge in normoxic water. In a second experiment, we assessed the opercular beat frequency before, during, and after hypoxic exposure. Hemoglobin concentrations and hematocrit were significantly different between fish held at 5°C vs. 15°C and also significantly different between normoxia prior to hypoxia and following recovery. Plasma lactate concentrations increased following hypoxia at both temperatures, indicative of an increase in anaerobic metabolism. In contrast, a significant increase in plasma glucose concentrations in response to hypoxia only occurred at 5°C, suggesting different fuel demands under different temperatures. Changes in opercular beat frequency (OBF) were dependent on temperature. At 5°C, OBF increased upon exposure to hypoxia, but returned to pre-exposure levels within 35 min for the remainder of the experiment. During hypoxia at 15°C, OBF increased very briefly, but then rapidly (within 20 min) decreased to levels below control values. Following a return to normoxia, OBF quickly increased to control levels. Overall, these findings suggest that Atlantic sturgeons are relatively tolerant to short-term and severe hypoxic stress, and the strategies for hypoxia tolerance may be temperature dependent.  相似文献   
6.
Red clover cultivars, including diploid and tetraploid, are commonly used in legume‐based pasture mixtures. However, information on nodulation under different starter N regimens is limited. We hypothesized that there is genetic variability among different red clover cultivars for nodulation. A root hair deformation assay was conducted using three diploid (AC Christie, Tapani and CRS15) and three tetraploid (Tempus, CRS18 and CRS39) red clover cultivars by inoculating them with Rhizobium leguminosarum biovar trifolii. Nodulation and morphological characteristics of two selected red clover cultivars, AC Christie and Tempus, were determined under five starter N concentrations (0, 0.2, 0.4, 0.8 and 1.6 mg per plant). Inoculation with rhizobia increased root hair deformation with significant interaction across cultivars. Nodulation was delayed under high starter N concentrations, and genotypic differences were evident for days‐to‐nodule initiation. There was a positive quadratic response to starter N for AC Christie and a negative quadratic response for Tempus for nodulation. Tempus had more active nodules (92 %) than AC Christie (73 %). The genetic variability of red clover cultivars should be considered in N fixation studies and their response to availability of initial N.  相似文献   
7.
8.
Forty ewes were allocated into one of four groups (n = 10) and were treated with albendazole (ALB) (3.8 mg kg(-1)) before lambing (group A), with ALB before and after lambing (group B), with moxidectin (MXD) (0.2 mg kg(-1)) before lambing (group C) or were untreated controls (group D). Counts of nematode eggs in faeces and coprocultures were carried out during the study, as well as ewes' milk yield measurements and lamb weighings. Pre-treatment mean eggs per gram (epg) counts were 640, 715, 625 and 630 for groups A, B, C and D, respectively (P > 0.05); respective counts 21 days after treatment were 5, 0, 0 and 690 epg, whilst 70 days after treatment they were 380, 145, 40 and 1120 epg. Mean lactation milk yield was 3527.5, 3893.5, 3786.4 and 3285.9 ml for groups A, B, C and D, respectively; no significant difference was evident among the four groups in milk yield collected during the suckling period, although subsequently, group B or C ewes yielded significantly more milk than controls (P < 0.05). Mean birthweight of lambs were 3.56, 3.45, 3.59 and 3.26 kg for groups A, B, C and D, respectively (P = 0.045); subsequently, lambs from treated ewes were significantly heavier than lambs from control animals (P < 0.001). We conclude that anti-parasitic treatment during the last month of pregnancy contributed to an increased birthweight of lambs of treated ewes, whilst the cumulative effect of two doses of ALB or the long persistent efficacy of MXD provided a longer protection of animals against new parasitic infections and contributed to a lactation persistence.  相似文献   
9.
Small ruminant lentivirus (SRLV) infections are widespread in Greece, but SRLVs have never been isolated and characterized. In this study, we present the sequence of a 574-nucleotide (191-amino acid) region of the gag gene of SRLV strains from four sheep and one goat from a single geographic area of Greece. All five sequences appeared to be closely related at both nucleotide (2.1-14.2% variation) and deduced amino acid (1.6-4.2% variation) level. Greek SRLV strains were closer to ovine prototypic strains (average divergence 16.8%) than to the caprine strain CAEV-Co (21% divergence). By amino acid composition, the Greek SRLVs were on the average more than twice as distant from CAEV-Co as from other ovine strains. Phylogenetic analysis suggested that Greek strains segregate into a unique group, separate from, but related to, other ovine prototype sequences.  相似文献   
10.
Genetic variability of encephalomyocarditis virus (EMCV) isolates   总被引:4,自引:0,他引:4  
In order to evaluate the variability of encephalomyocarditis virus (EMCV), field isolates originating from different European regions and inducing different clinical pictures in pigs have been molecularly characterised. The regions targeted were the poly(C) tract, a part of the 5'-UTR (360 nucleotides), the Leader gene (201 nucleotides), the complete capsid coding region (2502 nucleotides), the 2A gene (403 nucleotides), the end of the 3D polymerase gene (305 nucleotides) and the 3'-UTR (123 nucleotides). Analyses have also been performed on a virulent field isolate, which had been subjected to serial passages in vivo and in vitro resulting, in the case of the in vitro passaged virus, in attenuation, as demonstrated by animal experiments. The present study shows that different clinical pictures, such as acute fatal myocarditis or reproductive failure, may not only be caused by EMCV isolates which are genetically diverse but also by the same isolate. Thus no correlation could be demonstrated between genotype and clinical disease. However, the European isolate which showed the highest genetic divergence also gave rise to a more complex clinical picture. Despite EMCV having been isolated from cases of acute fatal myocarditis in pigs in certain areas of the world for many years, clinical disease, including a variety of clinical pictures and pathogenicity, has only been recognised in Europe since 1986 and thus it can be considered an emerging disease in this region. These findings, associated with the reported phenotype changes of the virus under environmental changes (passages), along with its wide distribution among vertebrate species (including higher primates), shows the validity of considering EMCV as a potential pathogen for recipients in xenotransplantation.  相似文献   
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