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1.
The aim of this experiment was to compare the level of fish female stress during induced reproduction with pituitary extract by two different methods, natural and semiextruded. The reproductive efficiency was 62.5% in the seminatural treatment and 100% in the extruded. Obtained egg volume was 5200 ml and 4000 ml, for seminatural and extruded treatments respectively. The mean number of eggs was 46.7 for the seminatural and 52.0 and for the extruded treatment. The percentage of viable eggs was, respectively, 87.2% and 8.17% for the natural treatment and extruded semimethods. Blood samples were collected to quantify cortisol and glucose levels, as well as red cell series and lymphocyte count. Fishes submitted to induction procedures showed elevated cortisol and glucose levels, compared to the control animals. The results for haematocrit, haemoglobin concentration and red blood cell count showed no significant differences among groups. Significant differences found in the number of lymphocytes and monocytes suggest the general adaptation syndrome. Our results suggest the reproductive induction process with extrusion of gametes as a more stressful method than seminatural reproduction process.  相似文献   
2.
Viruses may be viewed as genetic information whose success depends on avoiding elimination from individual hosts, or, if this is not possible, in persisting in the population of their hosts. The immune system represents the crucial defense mechanism responsible for the elimination of viruses from individual hosts and for the establishment of immunity that prevents a recurring infection by the same virus. Herd immunity, i.e., immunity of the population against infection resulting from the immunity of a certain fraction of the individuals of the population, represents an important concept in the interaction of viruses with their hosts. Thus, if the number of susceptible hosts decreases below a critical threshold, viruses may risk extinction because they literally run out of substrate. This possibility is increased due to the viruses' low resistance to inactivation outside their hosts by physical influences, such as heat and ultraviolet radiation. Some viruses have adopted a strategy of dual host tropism, i.e., they may reside in reservoir hosts that permit them to survive for extended periods of times. Examples of such viruses are the large and taxonomically diverse group of arboviruses. Moreover, although not normally discussed under this aspect, influenza viruses can also be said to have adopted this strategy, in view of water fowl representing reservoir hosts from which complete viruses may directly cross over to mammals, as was the case with the equine Jilin (Guo et al., 1995) or, more recently, the H5 subtype of influenza virus in humans (Shortridge et al., 1998). In addition, influenza viruses of birds may be transmitted, albeit only partially, through genetic reassortment (Shu et al., 1996).  相似文献   
3.
The pharmacokinetics and intramuscular (i.m.) bioavailability of cefoperazone and cefamandole (20mg/kg) were investigated in dogs and the findings related to minimal inhibitory concentrations (MICs) for 90 bacterial strains isolated clinically from dogs. The MICs of cefamandole for Staphylococcus intermedius (MIC(90) 0.125 microg/mL) were lower than those of cefoperazone (MIC(90) 0.5 micro/mL) although the latter was more effective against Escherichia coli strains (MIC(90) 2.0 microg/mL vs. 4.0 microg/mL). The pharmacokinetics of the drugs after intravenous administrations were similar: a rapid distribution phase was followed by a slower elimination phase (t((1/2)lambda2) 84.0+/-21.3 min for cefoperazone and 81.4+/-9.7 min for cefamandole). The apparent volume of distribution and body clearance were 0.233 L/kg and 1.96 mL/kg/min for cefoperazone, 0.190 L/kg and 1.76 mL/kg/min for cefamandole. After i.m. administration the bioavailability and peak serum concentration of cefamandole (85.1+/-13.5% and 35.9+/-5.4 microg/mL) were significantly higher than cefoperazone (41.4+/-7.1% and 24.5+/-3.0 micog/mL), but not the serum half-lives (t(1/2el) 134.3+/-12.6 min for cefoperazone and 145.4+/-12.3 min for cefamandole). The time above MIC(90) indicated that cefamandole can be administered once daily to dogs for the treatment of staphylococcal infections (T>MIC for S. intermedius 23.8+/-0.3 and for Staphylococcus aureus 21.6+/-0.6h).  相似文献   
4.
OBJECTIVE: To investigate whether volumetric capnography indices could be used to differentiate between horses without recurrent airway obstruction (RAO) and horses with RAO that were in clinical remission or that had clinically apparent RAO. ANIMALS: 70 adult Swiss Warmblood horses (20 used for pleasure riding and 50 used for dressage or show jumping). PROCEDURE: Horses were allocated to 4 groups on the basis of history, clinical signs, results of endoscopy, and cytologic findings (group 1, 21 healthy horses; group 2, 22 horses with RAO that were in remission; group 3, 16 horses with mild RAO; group 4, 11 horses with exacerbated RAO). Expiratory volume and CO2 curves were recorded by use of a computerized ultrasonic spirometer. Volumetric capnograms were plotted, and derived indices were calculated. RESULTS: Dead-space volume (VD) was calculated by use of the Bohr equation (VD(Bohr)) and for physiologic VD (VD(phys)). Ratios for VD(Bohr) to expiratory tidal volume (VT) and VD(phys) to V(T) as well as an index of effective CO2 elimination were significantly different among groups of horses. Age and use of the horses also significantly affected volumetric capnography indices. CONCLUSIONS AND CLINICAL RELEVANCE: Ratios of VD(Bohr) to VT and VD(phys) to VT as well as an index of effective CO2 elimination were sufficiently sensitive measures to distinguish between healthy horses and horses with RAO in remission. To optimize the ability of volumetric capnography indices to differentiate among horses in heterogeneous populations, it is important to account for effects of age and specific use of the horses.  相似文献   
5.
The rabies epidemic that reached Switzerland in 1967 developed in response to landscape factors as long as no efficient control strategies were available. The landscape acted either as barrier to the spread of rabies, or it influenced the density of red foxes and thus the habitat of the epidemic. Following the first cases in the canton of Schaffhausen, the whole northwestern Switzerland was infected followed by the eastern Alps, large parts of the Plateau and the Jura mountains. In 1978, in the canton of Valais, the first campaigns of oral immunization of foxes against rabies started. The design of vaccination campaigns during the next two decades was always closely linked to landscape features. Thus, it was possible to free first the Alps and then the Plateau from rabies and finally, at the end of the 1990s, to eliminate it completely within the country. We describe the entire development of the epidemic within the period of 30 years from the first infection up to the last registered case and the final vaccination campaign.  相似文献   
6.
A semi-nested polymerase chain reaction (snPCR) for detecting proviral DNA of ovine lentivirus (OvLV) in peripheral blood mononuclear cells was developed. Primers for snPCR were situated within the gag gene of the Maedi-Visna virus (MVV) genome. A comparison between the snPCR and serological tests (agar gel immunodiffusion test, immunoblot) were performed using 98 ovine blood samples. Thirty (30.6%) of the 98 sheep examined had antibodies specific for the MVV. PCR showed 21 of them to be positive and nine seropositive animals to be PCR negative. Six of the 68 serologically negative sheep were found to be PCR positive, probably due to delayed seroconversion. The PCR amplification products of these six sheep were sequenced and subjected to phylogenetic analysis. The resulting phylogenetic tree of partial gag gene sequences confirmed that the ovine lentivirus genotype in the Czech Republic is more closely related to the prototype MVV isolates than to the caprine arthritis encephalitis viruses.  相似文献   
7.

Background

The authors report the first case of feline gastric actinomycosis associated with infection by Actinomyces hordeovulneris.

Case presentation

A 4-year-old, neutered male, semi-feral European cat, with a 1 year history of chronic vomiting, was referred to the clinic. Abdominal ultrasound examination identified a hypoechoic focal transmural thickening with loss of normal wall layering and hyperechoic speckles at the gastric body. Initial gastroscopic examination showed a tumour-like gastric mass with an ulcerated depression at the level of the greater curvature. Histologic examination of endoscopic biopsy specimens was consistent with a severe lymphoplasmacytic gastritis. After 2 months, due to persistence of abdominal discomfort, surgical exploration and intraoperative sampling of gross abnormalities was recommended. Full thickness gastric wall biopsies, and fine needle aspiration of the gastric thickening and gastric lymph node, were performed. Histopathological examination identified a transmural pyogranulomatous gastritis. Aspirate samples of the gastric wall cultured positive, with colony morphology, biochemical testing and PCR of the 16 s rRNA gene compatible with Actinomyces hordeovulneris. After 4 months of treatment with cefovecin (8 mg/kg subcutaneously every 14 days), the vomiting completely resolved, as well as the ultrasonographic gastric alteration.

Conclusion

This case report of feline gastric actinomycosis, caused by Actinomyces hordeovulneris, suggests that gastric bacterial infection should be considered in cases of focal gastric wall thickening associated with chronic vomiting in the cat, which may otherwise closely resemble neoplastic disease. Once a diagnosis of actinomycosis was obtained, a correct treatment with antibiotic therapy can resolve it.
  相似文献   
8.
9.
To evaluate the potential benefits and risks associated with tea consumption it is important to identify the constituents of this beverage. Levels of some minerals, caffeine and catechins in green tea samples commercialized in Portugal were evaluated. Potassium is the metal present in larger amount (92–151 mg/l). The content of sodium, calcium, fluoride, aluminium, manganese and iron were 35–69, 1.9–3.5, 0.80–2.0, 1.0–2.2, 0.52–1.9, 0.020–0.128 mg/l, respectively. Chromium and selenium were not detected. The resulting data showed considerable variability in catechins content. The levels of epigallocatechin gallate (EGCG) ranged from 117 to 442 mg/l, epicatechin 3-gallate (EGC) from 203 to 471 mg/l, epigallocatechin (ECG) from 16.9 to 150 mg/l, epicatechin (EC) from 25 to 81 mg/l and catechin (C) from 9.03 to 115 mg/l. Caffeine contents in the green tea infusions studied were between 141–338 mg/l. Green tea infusions provide significant amounts of catechins and could be an important source of some minerals.  相似文献   
10.
Plant Foods for Human Nutrition - Silver linden (Tilia tomentosa Moench, TtM) flowers possess several health-promoting properties, especially at the neurological level, such as intestinal...  相似文献   
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