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The recent emergence of avian pneumovirus (APV) infection among US turkey flocks has resulted in a major economic threat to the turkey industry. In order to elucidate the molecular epidemiology of APV, comparative sequence analysis of the fusion (F) protein gene of APV was performed for 3 cell culture-adapted isolates and 10 APV positive clinical samples recovered from US turkey flocks. Relatively modest levels of nucleotide and amino acid sequence divergence were identified, suggesting the prevalence of a single lineage of APV among US turkey flocks. Additionally, numerous polymorphisms were identified that were only represented in the clinical samples but not in the in vitro propagated isolates of APV. Phylogenetic analyses confirm that the subtype of APV circulating in the upper Midwestern United States is evolutionarily related to, but distinct from, European APV subgroups A and B. Overall, the results of the present investigation suggest that there has been only a single recent introduction of APV into US turkey populations in the upper Midwestern United States.  相似文献   
63.
Providencia spp. are Gram negative bacteria, belonging to the family Enterobacteriaceae and are responsible for gastrointestinal disorders both in humans and animals. We report on the isolation of multi-drug resistant Providencia spp. (n=4) from animal manure. The isolates were found to be resistant to clindamycin and to tetracycline, as well as to the macrolide and sulphonamide groups of antibiotics.  相似文献   
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The potential of potato flour as a humectant (anti-staling agent) was investigated. The experiment utilised eight variants of potato flour, prepared from processing cultivar K. Chipsona-1 and table cultivar K. Laukar, in muffins as a bakery product. On the basis of higher values of water retention and water absorption, and comparatively lower values of setback and flavour intensity, grilled (180 W for 25 min) potato flour from cultivar K. Laukar (GPF-T) was selected for muffin preparation. For optimization, muffins were prepared with GPF-T at 1, 3, 5 and 7% (w/w) level in the formulation. The storage study was conducted for 8 days at 25?±?2 °C and 55?±?5% RH. It was concluded from the product characterisation, sensory evaluation and storage study that 3% GPF-T can be used as a low-cost alternative to commercially available humectants for muffin preparation. Research findings may be adopted by small-scale industry entrepreneurs to delay the staling of muffins two-fold without adversely affecting the sensory scores.  相似文献   
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Twenty-eight hundred and seventy-two cases of respiratory disease in pigs were analyzed for their etiologic agents. Two or more pathogens were detected from 88.2% of the cases, indicating that porcine reproductive and respiratory syndrome virus (PRRSV) or swine influenza virus (SIV) combined with other bacterial agents was a common cause for porcine respiratory diseases in the mid-western USA.  相似文献   
68.
The duration of immunity after a single dose of a cold-adapted strain of Avian pneumovirus (APV) was studied. Turkeys were vaccinated at 1 wk of age and challenged with virulent virus 3, 7, 10, and 14 wk later. Nonvaccinated groups were also challenged at the same times. No clinical signs were observed in the vaccinated birds after vaccination or after any challenge. No viral RNA was shed by the vaccinated birds after any challenge. The nonvaccinated birds shed viral RNA after all challenges. Avian pneumovirus-specific humoral antibodies were detected in the vaccinated birds until 14 wk after vaccination. The results of this preliminary study indicate that inoculation with a single dose of a cold-adapted strain of APV at 1 wk of age provides protection until 15 wk of age.  相似文献   
69.
Runoff from grazing pasture lands can impact water quality in receiving streams if not well managed. Management consists of conservation practices to reduce runoff and pollutants transport. Simulation models have been effectively used to design and implement these conservation practices. The Agricultural Policy Environmental Extender (APEX), a process-based hydrologic model, was used in this study to simulate the management impacts on surface runoff from three small grazed pasture watersheds located at the North Appalachian Experimental Watersheds near Coshocton, Ohio. Specific objectives of this study were to 1) calibrate the APEX model and test runoff predictions against measured runoff and 2) simulate the long-term impacts of different management scenarios on surface runoff. Results show that the APEX model simulated surface runoff reasonably well with the coefficient of determination (R2) and Nash-Sutcliffe efficiency values varying from 0.49 to 0.72 and from 0.25 to 0.60 for calibration and validation, respectively. After validation, the APEX model was run for 37 yr (1975 ? 2011) for long-term scenarios to analyze the impacts of soil properties and management on surface runoff. Data from this study indicated that keeping the watershed land use as a hay meadow instead of grazing significantly reduced cumulative runoff by 58 ? 67%. Buffer strips of perennial grasses resulted in decreased simulated runoff. To simulate the impacts of soils on runoff, the surface (0 ? 5 cm) soil properties of the toe position were applied to the entire grazed watershed. Subsequently, the increase in soil richness resulted in reduction (≤ 5%) in surface runoff. The simulation results from the present study demonstrate the benefits of hayed meadow over grazed pasture and further predict the decreased trend of runoff due to soil properties change and buffer strips.  相似文献   
70.
Biomass plays a vital role in the energy supply of many developing countries. It is the major energy source for the rural population of Nepal, where 70 % of the total energy is derived from woody plant biomass in the form of fuelwood. The main aim of this study is to describe the fuelwood consumption pattern and the role of community forests and trees on private farmland in biomass supply to rural households in Nepal. The study investigates whether demography and socioeconomic attributes of households affect fuelwood consumption. A household survey was conducted, along with measurements of fuelwood mass for six community forest user groups in Dolakha district of Nepal. Average daily household fuelwood consumption was estimated to be 8.4 kg, giving a mean annual consumption of 3060 kg per household. Per capita fuelwood consumption per day was found to be 1.7 kg. Total fuelwood consumption of households is significantly correlated with household size, ownership of cultivated irrigated terraces and number of livestock per household, and negatively significantly correlated with ownership of cultivated rain-fed terraces. Fuelwood consumption varies significantly between seasons. Among various sources of biomass energy, fuelwood from community forests contributes 23 % and trees on private farmland contribute 12 %. The rest is provided from other biomass sources, including the remains of fodder collected from private farmland vegetation, wood previously used for fences and trellises in private farmland, crop residues, and purchased fuelwood.  相似文献   
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