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71.
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Newcastle disease (ND) epizootics in some European countries after the World War II were caused by ND virus (NDV) of multiple genotypes (IV-VIIa) occurring sequentially and/or simultaneously. This study was carried out to characterise the genetic composition of NDV strains during the outbreaks in the territory of the former Yugoslavia in order to enhance our understanding of the relationships of past epizootics in Europe. Sixty-eight NDV strains isolated between 1979 and 2002 were analysed by restriction enzyme digestion and partial sequencing of the fusion protein gene. All isolates were placed in genotype V, an exotic type, that was introduced to western Europe in 1970. Residue substitution analysis has allowed the recognition of four genetic variants, Vb1-Vb4, and the tracing of their movements. Vb1, a dominant variant in Bulgaria from the late 1970s, was also wide spread in the former Yugoslavia throughout the period under investigation. Vb2, a variant occurring in the neighbouring countries in the early 1970s could be the founder of the epidemic in Yugoslavia and it was present up to the late 1980s. Variants Vb3 and Vb4 could be found only after 1987. In conclusion, the ND outbreaks in Yugoslavia were part of the epizootic wave due to genotype V viruses that started in western Europe in 1970 and became endemic in the region. Inter-country transmission occurred for all variants, and Vb3 and Vb4 might have evolved during the endemic period.  相似文献   
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Zusammenfassung Aus den hier dargelegten Untersuchungsergebnissen über die Wirkung niedriger Dosen von DDT-Präparaten lassen sich für die Forschung und Praxis folgende Schlüsse ziehen:1. Nicht nur gegen Schwammspinner- und andere Raupen, welchen eine starke Veranlagung für Virosen und andere Krankheiten eigen ist, sondern auch gegen viele andere Insekten könnte man mit niedrigerer Dosierung erfolgreich vorgehen.2. Mit niedrigeren Dosen von DDT kann man 100%ige Mortalität der Raupen herbeiführen, gleichzeitig aber die Sterblichkeit der nützlichen Insekten auf ein Zehntel gegenüber Normaldosierung senken.3. Überall dort, wo wir auf ausreichende Wirkung subletaler Dosen rechnen können, sollten zur Schonung der Biocönose schwächere Konzentrationen angewendet werden.4. Die Befürchtung eine nachträglichen Resistenz ist vorläufig unbegründet, da sich die subletalen Dosen als Auslöser latenter Erkrankungen erwiesen haben.5. Die Wirkung niedriger Dosen auf jene Insekten mit hoher DDT-Empfindlichkeit, die nicht zu den latent-virotischen Arten zählen, müßte genauer untersucht werden, um über die praktische Bedeutung dieser Erscheinung Sicherheit zu gewinnen.6. Die Anwendung subletaler und kleinerer Insektiziddosen wird in Zukunft große Bedeutung erlangen, da sie die Biocönosen viel weniger stört und die biologische Schädlingsbekämpfung unterstützt, also einen Weg zur integrierten Schädlingsbekämpfung darstellt.  相似文献   
75.
This case report describes the diagnosis, demonstration and treatment of feline herpes virus-induced facial dermatitis in a cat. The cat was successfully treated with interferon omega (IFN-omega).  相似文献   
76.
Experimental groups of 15 susceptible 3-week-old turkeys were inoculated oculonasally with avian metapneumovirus (APV) subtype A and susceptible Escherichia coli O2:K1 and Ornithobacterium rhinotracheale (ORT) bacteria, with a 3 days interval between viral and bacterial inoculation and approximately 8h between the two bacterial inoculations. The aims of the present study were to assess the efficacy of drinking-water administration of enrofloxacin for 3 and 5 days, amoxicillin for 5 days and florfenicol for 5 days for the treatment of the resulting respiratory disease, based on clinical and bacteriological examinations. Antimicrobial treatment started 1 day after dual bacterial inoculation. After infection, the birds were examined and scored for clinical signs daily, weighed at different times, and their tracheae swabbed daily. Five birds were euthanised and examined for macroscopic lesions at necropsy at 5 days post-bacterial inoculation (dpbi) and the remainder at 15dpbi. Samples of the turbinates, trachea, lungs, sinuses, air sacs, heart, pericardium and liver were collected for bacteriological examination. Recovery from respiratory disease caused by an APV/E. coli/ORT triple infection in 3-week-old turkey poults was overall most successful after enrofloxacin treatment, irrespective of treatment duration, followed by florfenicol treatment. Compared with the untreated group, clinical signs as well as ORT and E. coli multiplication in the respiratory tract were significantly reduced by both enrofloxacin treatments and the florfenicol treatment, with the enrofloxacin treatments showing significantly better reductions than the florfenicol treatment. Five-day treatment with amoxicillin, compared with the untreated group, did not cause a significant reduction in any of the aforementioned parameters.  相似文献   
77.
The effect of fasting and refeeding on total antioxidant status (TAS), glutathione peroxidase (GSH-Px) activity and concentration of some non-enzymatic antioxidant compounds was studied in cockerels and pullets. Blood was collected before and after 48-h fasting and 24 h after refeeding. In cockerels, fasting resulted in a significant decrease of TAS and uric acid concentration. After refeeding, the concentration of TAS remained significantly lower as compared to the control level. At the same time, blood plasma level of total lipids increased in comparison to the control and post-fasting values. In pullets, fasting resulted in a significant decrease of whole blood haemolysate GSH-Px activity and blood plasma concentrations of albumin and uric acid. Simultaneously, a significant increase in total lipids and cholesterol was obtained. In pullets, refeeding resulted in a further decrease of TAS to undetectable values, a significant decrease of blood plasma cholesterol, and a significant increase of GSH-Px in the whole blood haemolysate and in blood plasma uric acid content. The results indicate that fasting has a negative impact on the antioxidant defence system of the blood, which leads to a reduced resistance to oxidative stress in both cockerels and pullets. However, pullets seem to be more susceptible to fasting-provoked oxidative stress than cockerels.  相似文献   
78.
ABSTRACT

Biofortification experiments with three winter wheat cultivars treated with sodium selenate through foliar- and soil-fertilisation were conducted at two locations in Croatia and Serbia in two consecutive years to increase the selenium (Se) concentration in bread-making wheat grain. The treatments were: (a) 5?g?ha?1 Se foliar-, (b) 10?g?ha?1 Se foliar- and (c) 10?g?ha?1 Se in soil surface-application and they were compared with (d) control. Both Se foliar- and soil-fertilisation increased the Se concentration in grains from 2.6- to 4.6-fold. The concentration in grain was highest with Se foliar-fertilisation of 10?g?ha?1 and it was increased by 29–32?µg Se kg?1 dry weight for each gram of Se applied per ha. The wheat cultivars differed in grain yield and Se uptake (g?ha?1 Se). However, on average, there were no differences between wheat cultivars with respect to Se grain concentrations. Agronomic use efficiency (by grain) was significantly higher for Se foliar- (19%) than for soil-fertilisation (13%). It can be concluded that agronomic biofortification of winter wheat can be effective in increasing Se grain concentration, where the efficiency depends on the rate of Se applied, application method and local environmental conditions rather than on cultivar differences.  相似文献   
79.
The aim of the current study was to investigate if there are any health effects of long-term consumption of organically grown crops using a rat model. Crops were retrieved over two years from a long-term field trial at three different locations in Denmark, using three different cultivation systems (OA, organic based on livestock manure; OB, organic based on green manure; and C, conventional with mineral fertilizers and pesticides) with two field replicates. The cultivation system had an impact on the nutritional quality, affecting γ-tocopherol, some amino acids, and fatty acid composition. Additionally, the nutritional quality was affected by harvest year and location. However, harvest year and location rather than cultivation system affected the measured health biomarkers. In conclusion, the differences in dietary treatments composed of ingredients from different cultivation systems did not lead to significant differences in the measured health biomarkers, except for a significant difference in plasma IgG levels.  相似文献   
80.
This work presents the results of 4 years long monitoring of concentrations of SO2 gas and PM10 in the urban area around the copper smelter in Bor. The contents of heavy metals Pb, Cd, Cu, Ni, and As in PM10 were determined and obtained values were compared to the limit values provided in EU Directives. Manifold excess concentrations of all the components in the atmosphere of the urban area of the townsite Bor were registered. Through application of a multi-criteria analysis by using PROMETHEE/GAIA method, the zones were ranked according to the level of pollution.  相似文献   
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