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211.
Guillén Llera JL López García ML Martín Reinoso E De Vivar González R 《Veterinary parasitology》2002,109(3-4):185-190
A mixed indirect fluorescence antibody test (IFAT), based on cultured promastigotes Leishmania infantum and formol-inactivated suspension of cells infected with the bacteria Ehrlichia canis, was applied to make a differential diagnosis between canine ehrlichiosis and leishmaniosis. A titre greater than 80 was considered positive for antibodies to E. canis and suggestive of antibodies to L. infantum. Positive sera were titrated subsequently by serial dilutions to confirm antibodies positive to Leishmania and establishing the antibody titre of both pathogens. Fluorescence was absent with negative control sera and background staining was minimal. No serological cross-reactions between positive sera for L. infantum or E. canis were detected. Results obtained by mixed IFAT did not differ when the same serum IFAT standard was compared. The test showed equivalent sensitivity (100%). The specifities were 100% for L. infantum and 98.5% for E. canis. The equivalence in sensitivity was confirmed by calculating the correlation coefficient between IFAT standards and mixed IFAT (r>or=0.99 for both pathogens). The results of our investigations demonstrated that mixed IFAT is a specific means of establishing serological differential diagnosis of canine leishmaniosis and ehrlichiosis. 相似文献
212.
Chiaradia E Gaiti A Scaringi L Cornacchione P Marconi P Avellini L 《Veterinary research》2002,33(6):661-668
To better define the species-specific antioxidant systems and to ascertain the influence of the intracellular redox status on the immune system of different animal species, we determined lymphocyte glutathione peroxidase (GSHPx) activity, plasmatic glutathione levels (GSH) and the effect of H2O2 on the responsiveness of lymphocytes to proliferative stimuli. Among the three species considered, sheep presented the lowest plasmatic GSH and the highest lymphocyte GSHPx activity. On the contrary, dogs showed an inverted pattern (high GSH - low GSHPx). Horses displayed intermediate values for both parameters analysed. The effect of H2O2 on the proliferative capacity of lymphocytes was the same for all three species; the 200 microM dose in particular was strongly inhibiting. Each species, however, showed different rates of inhibition: sheep exhibited the highest sensitivity to the antiproliferative effect of H2O2. Our results confirmed that high H2O2 concentrations (200 microM) are noxious for the cellular functions of all animals; however this effect is mediated by a rigorously species-specific relationship between the intracellular reactive oxygen species (ROS) and the molecular systems involved in cell proliferation. 相似文献
213.
Olby N Muñana K De Risio L Sebestyen P Hansen B 《Journal of the American Animal Hospital Association》2002,38(4):321-326
Two dogs were presented to North Carolina State University Veterinary Teaching Hospital following blunt trauma to the head delivered by a horse kick. On presentation, both dogs had resolving clinical signs directly related to the head trauma, but both also had compromise to their upper airway as a result of indirect injury to the soft tissues of the neck, visible on plain radiographs. One dog made a full recovery following a period of assisted ventilation. The other dog was euthanized at the request of the owner. These injuries illustrate the importance of evaluating the cervical spine and soft tissues of the neck following blunt trauma to the head. 相似文献
214.
De Vico G Sfacteria A Maiolino P Mazzullo G 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2002,31(1):16-18
Background — Nuclear morphometry may provide useful diagnostic and prognostic information for neoplasms in animals. Most available data have been obtained from histologic sections. Nuclear morphometry of cytologic smears may provide important pre-operative information.
Objectives — The goal of this study was to compare nuclear morphometric parameters in cytologic smears and histologic sections from spontaneous canine tumors.
Methods — Mean nuclear area (MNA), mean nuclear perimeter (MNP), mean nuclear form factor (FF; nuclear perimeter2 /4π nuclear area) and their respective SDs were assessed by image analysis of both hematoxylin and eosin-stained histologic sections and May-Grünwald-Giemsa-stained cytologic smears from the same case in 20 spontaneous canine tumors of different histogenesis. The above parameters were selected as being the best morphometric tools for measuring variation in shape and size in cells after neoplastic transformation. Data were compared by ANOVA with P<.01 considered significant.
Results — There was a significant difference between histologic and cytologic specimens for MNA, MNP, and their SDs. Only the differences between FF and the SD of FF were not statistically significant.
Conclusions — Only nuclear morphometric data related to nuclear shape and nuclear shape variability are comparable between histologic and cytologic specimens. Nuclear area and perimeter may be affected by the different fixation and smear preparation techniques used in histology and cytology. 相似文献
Objectives — The goal of this study was to compare nuclear morphometric parameters in cytologic smears and histologic sections from spontaneous canine tumors.
Methods — Mean nuclear area (MNA), mean nuclear perimeter (MNP), mean nuclear form factor (FF; nuclear perimeter
Results — There was a significant difference between histologic and cytologic specimens for MNA, MNP, and their SDs. Only the differences between FF and the SD of FF were not statistically significant.
Conclusions — Only nuclear morphometric data related to nuclear shape and nuclear shape variability are comparable between histologic and cytologic specimens. Nuclear area and perimeter may be affected by the different fixation and smear preparation techniques used in histology and cytology. 相似文献
215.
Leptin and leptin receptors during malaria infection in mice 总被引:2,自引:0,他引:2
Leptin, which is involved in a range of physiological processes, could be an important factor in the pathogenesis of malaria. We found that levels of leptin in serum and urine in Plasmodium berghei-infected mice increased progressively after infection, reaching a maximum value on day 6 post-infection. Serum values were approximately five-fold higher in infected mice than in non-infected controls. A similar relation was found for values of leptin in urine. Soluble leptin receptor levels also increased significantly in serum, more or less in line with the leptin increase. Our work represents the first report of visibly augmented leptin and soluble leptin receptor secretion in malarial infection. 相似文献
216.
Delahay RJ De Leeuw AN Barlow AM Clifton-hadley RS Cheeseman CL 《Veterinary journal (London, England : 1997)》2002,164(2):90-105
Bovine tuberculosis caused by Mycobacterium bovis is a zoonotic infection with a wide range of mammalian hosts. In parts of the UK M. bovis infection in cattle is a persistent problem. The European badger (Meles meles) is implicated in the transmission of M. bovis to cattle, and is widely believed to constitute the most important reservoir of infection in UK wildlife. However, few studies have been carried out on the status of M. bovis infection in other UK mammals. In this review we present information on the incidence and pathology of M. bovis infection in UK wild mammals from both published and previously unpublished sources. Although the evidence does not support the existence of a significant self-maintaining reservoir of infection in any wild mammal other than the badger, there is a clear lack of sufficient data to rule out the involvement of other species. In the light of this and the dynamic nature of epidemiological patterns, further surveillance for M. bovis infection in UK wild mammals, using modern methods of diagnosis, is essential. 相似文献
217.
ABSTRACT Production of conidia of Penicillium oxalicum (ATCC number pending), a biocontrol agent of Fusarium oxysporum f. sp. lycopersici, was tested in liquid and solid fermentation. P. oxalicum produced 250-fold more conidia in solid than in liquid fermentation at 30 days after inoculation of substrate. Solid fermentation was carried out in plastic bags (600 cm(3)) especially designed for solid fermentation (VALMIC) containing 50 g of peat/vermiculite (PV) (1:1, wt/wt) with 40% moisture, sealed, sterilized, and then inoculated with 1 ml of a conidial suspension of P. oxalicum (10(5) conidia g(-1) dry substrate), sealed again, and incubated in darkness at 20 to 25 degrees C for 30 days. Addition of amendments to PV in a proportion of 0.5 (wt/wt) significantly increased conidial production of P. oxalicum. The best production was obtained on PV plus meal of cereal grains (barley) or leguminous seeds (lentil) (100-fold higher). Conidial production obtained after 5 days of inoculation was similar to that obtained at 30 days. However, viability of conidia produced in PV plus lentil meal was 35% higher than that of conidia produced in PV plus barley meal. Changes in proportions (1:1:0.5, wt/wt/wt; 1:1:1, wt/wt/wt; 1:0.5:0.5, wt/wt/wt; 1:1:0.5, vol/vol/vol) of components of the substrate (peat/vermiculite/lentil meal) did not enhance production or viability of conidia. Optimal initial moisture in the substrate was 30 to 40%. At lower moistures, significant reductions of production of conidia were observed, particularly at 10%. There was a general decline in the number of conidia in bags with time of storage at -80, -20, 4, and 25 degrees C, or at room temperature (range from 30 to 15 degrees C), with the highest decline occurring from 60 to 180 days. Conidial viability also was reduced with time, except for conidia stored at -20 degrees C. Fresh conidia produced in solid fermentation system or those conidia stored at -20 degrees C for 180 days reduced Fusarium wilt of tomato by 49 and 61%, respectively. 相似文献
218.
De Guise S Bernier J Lapierre P Dufresne MM Dubreuil P Fournier M 《American journal of veterinary research》2000,61(3):339-344
OBJECTIVE: To study effects of in vitro exposure of bovine leukocytes to mercury, cadmium, and lead on phagocytosis, natural killer cell activity, and lymphocyte proliferation. SAMPLE POPULATION: Leukocytes from 6 nonpregnant Holstein heifers. PROCEDURE: Leukocytes were exposed in vitro to the aforementioned metals, and leukocyte functions were assessed. RESULTS: Phagocytosis was suppressed by 10(-5) to 10(-7) M CdCl2 and by 10(-5) and 10(-6) M HgCl2, but not 10(-7) M HgCl2 nor 10(-4) to 10(-6) M PbCl2. Spontaneous and concanavalin A- or phytohemagglutinin-stimulated proliferation of metal-treated bovine blood mononuclear cells was not significantly different from that of nontreated control cells, except for enhanced spontaneous proliferation in response to 10(-5) M HgCl2. When proliferation was expressed as a stimulation index, a dose-dependent increase of spontaneous proliferation was observed in response to exposure to HgCl2 and PbCl2. Compared with response to 10(-6) or 10(-7) M CdCl2, reduction of mitogen-induced and spontaneous proliferation was observed on exposure to 10(-5) M CdCl2. Natural killer cell activity against YAC-1 target cells, evaluated by flow cytometry, was decreased only in cells exposed to 10 M HgCl2. CONCLUSION AND CLINICAL RELEVANCE: Bovine leukocytes are susceptible to the immunomodulatory effects of in vitro exposure to heavy metals at concentrations equal to or higher than those at which similar effects are seen for leukocytes from most other animal species for which data are available for comparison. Exception is phagocytosis, which is severely affected by low concentrations of CdCl2 and HgCl2 in cattle. Reduction of defense mechanisms on exposure to metals could lead to increased susceptibility to potential pathogens. 相似文献
219.
In this study performed between 1993 and 1997, infectious bursal disease virus (IBDV) antibody titers and performance data were recorded in a vertically integrated monitoring scheme in order to make a follow-up from day-old parents down to the broilers at slaughter. All measured data were used two by two in a simple correlation study to calculate the degree to which they were linearly correlated. It appeared that high and/or uniform antibody titers in the parents were correlated with increased daily weight gain and decreased mortality and slaughterhouse condemnation in the broilers. Antibody titers and their CVs were negatively correlated in broiler parents and their offspring at day-old and even at slaughter. Results indicate that high and uniform antibody titers against IBDV in broiler parents are important for good performance of the broiler offspring, at least under the epidemiologic conditions of this study, which included the presence of very virulent IBDV strains in the field and the sole use of live intermediate vaccines in broilers as well as broiler parents. 相似文献
220.
Enhanced specific antibody response to bovine serum albumin in pigeons due to L-carnitine supplementation 总被引:1,自引:0,他引:1
Janssens GP Mast J Goddeeris BM Cox E Hesta M De Wilde RO 《British poultry science》2000,41(4):448-453
1. Thirty adult female pigeons (Columba livia domestica) were randomly divided into 3 equal groups; the 1st and 2nd groups were immunised with bovine serum albumin (BSA) at 0 and 20 d, the 2nd group also received 1 g L-carnitine per litre of drinking water from -5 to 25 d post-immunisation (dpi) and the 3rd group, a control group, received neither treatment. 2. Body weights and serum samples were taken at 0, 5, 10, 15, 20, 25, 30 and 35 dpi. 3. Both BSA-specific IgG and IgM responses were enhanced by about 10% by L-carnitine supplementation. 4. L-carnitine supplemented pigeons showed a higher water consumption. Body weight loss during the onset of the immune response showed a slight tendency to be counteracted by L-carnitine supplementation. 5. The impact of L-carnitine on resistance and resilience to an immunological challenge is discussed. 相似文献