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81.
This study was conducted to study absorption of glucosamine (GlucN) and chondroitin sulfate (CS) in horses immediately after feeding. Six mature mares were used in a replicated 3 × 3 Latin-square-designed experiment. The experiment consisted of three 15-day periods, which included 10 days of diet adaptation followed by a 5-day sampling period. Blood was drawn after feeding on one day during each sampling period. Horses were fed a control diet (40% hay, 60% concentrate) balanced to meet NRC requirements for maintenance of mature horses (NRC, Nutrient requirements of horses, 1989). In one experimental diet, 2.0 g CS and 5.5 g GlucN were added to the basal ration at each feeding. In the other experimental diet, 3.5 g CS and 8.5 g GlucN were added to the basal ration at each feeding. After collections, blood was centrifuged and plasma was harvested and stored until analyzed for the presence of each compound. Analyses for plasma GlucN were performed using high-performance liquid chromatography. CS in the plasma was analyzed using a color reagent, dimethylmethylene blue, followed by ultraviolet spectrophotometry. There were no significant differences (P < .05) in the concentration of either CS or GlucN in plasma, when comparing the three different diets. This leads to a conclusion that these compounds were not absorbed intact through the intestinal wall into the bloodstream. This poses a question as to whether oral forms of these compounds are absorbed and are able to migrate to joints through the blood to improve joint function.  相似文献   
82.
The aim of the present study was to determine whether arbuscular mycorrhizal (AM) inoculation with a biofertilizer containing clays as granular carriers, leek root pieces and Glomus intraradices spores could improve alkalinity tolerance of two cucumber genotypes, and to study the changes induced by AM at agronomical and physiological level. A greenhouse experiment was carried out to determine yield, growth, fruit quality, net photosynthesis (ACO2), electrolyte leakage, and mineral composition of two cucumber (Cucumis sativus L.) genotypes (hybrid “Ekron” or open-pollinated variety “Marketmore”) with inoculated and noninoculated arbuscular mycorrhizal biofertilizer. Plants were supplied with nutrient solutions at two pH values (6.0 or 8.1). The high pH nutrient solution had the same basic composition with an additional 10 mM NaHCO3 and 0.5 g l−1 CaCO3. The percentage root colonization was higher in “Marketmore” (21.8%) than “Ekron” (12.7%). Total and marketable yield and total biomass were significantly higher by 189%, 213%, and 77%, respectively, with Ekron in comparison to those recorded with Marketmore. The highest crop performance with Ekron in comparison to Marketmore was due to the improved nutritional status (higher N, P, K, Ca, Mg, Fe, Mn, and B), higher leaf area, and net photosynthesis. Increasing the concentration of NaHCO3 from 0 to 10 mM in the nutrient solution significantly decreased yield, plant growth, ACO2, N, P, Fe, Cu, Zn, Mn, and B concentration in leaf tissue, whereas the electrolyte leakage increased. The inoculated plants under alkaline conditions had higher total, marketable yield, and total biomass than noninoculated plant. Mycorrhizal cucumber plants grown under alkaline conditions had a higher macronutrient concentration in leaf tissue compared to noninoculated plants. The highest yield and biomass production in inoculated plants seems to be related to the capacity of maintaining higher net ACO2 and to a better nutritional status (high P, K, Mg, Fe, Zn, and Mn and low Na accumulation) in response to bicarbonate stress with respect to −AM plants.  相似文献   
83.

Background

In practical farming, there is often a need for short-term availability of information on the soil nutrient status.

Aims

To develop a new express method for the extraction of major plant-available nutrients and measurement of soil nutrients. In future, this method shall serve for in-field measurements of soil samples with an ion-sensitive field-effect transistor (ISFET).

Methods

Various extraction conditions such as type of extractant, soil-to-solution ratio, time, and intensity were investigated on a broad selection of dried soil samples in the laboratory. Based on 83 field-moist soil samples with varying clay contents, these conditions were compared to standard laboratory methods.

Results

With increasing extraction time, the nutrient concentrations increased. When the soil-to-solution ratio was reduced, a greater share of nutrients was extracted, independent of soil type. H2O and 0.01 M CaCl2 and standard calcium-acetate-lactate (CAL) solution proved to be too weak in the short period to reach the ISFET sensor measurement range. Higher concentrated CAL solutions performed much better. Finally, a 5-min CaCl2 extraction followed by the removal of an aliquot for the determination of soil pH and NO3 was found to be effective. The remaining solution was then mixed with 0.20 M CAL solution for the analysis of H2PO4 and K+ at 10 min of extra extraction time. This extraction method showed very good correlations with the values based on the German laboratory reference methods for pH (R2 = 0.91) and for nitrate (R2 = 0.95). For phosphorus and potassium, we obtained an R2 of 0.70 and 0.81, respectively, for all soils. When soils were grouped according to clay content higher correlations were found.

Conclusions

A new express method based on a wet-chemical approach with a soil preparation procedure was successfully developed and validated. This seems to be a valuable basis for future in-field measurements via ISFET.  相似文献   
84.
Iron-dependent outer membrane proteins (IROMPs) play an important role in bacterial pathogenesis and present several attributes of potential vaccine candidates. TBLASTN analysis of the Pasteurella multocida Pm70 genome using the same molecules of other bacterial pathogens as a query identified eight putative haemin and haemoglobin receptors for this organism. Quantitative binding assays have demonstrated that the proteins PM0040, PM0236, PM0741, PM1081, PM1428, PM0592 and HgbA bind both haemin and haemoglobin, whereas PM0576 and PM1282 ORFs only bind either haemoglobin or haemin, respectively. Furthermore, Western blot analysis showed that P. multocida-infected mice generate specific antibodies against PM0040, PM0236, PM0741, PM1081, PM1428, PM0592 and HgbA proteins. Nevertheless, inoculation of mice with any single one of these receptors alone did not protect against P. multocida infection.  相似文献   
85.
Tocopherols are compounds present in oilseeds with major effect on nutritional and technological properties of seed oils. Brassica spp. mainly contain varying concentrations of α‐tocopherol, with high vitamin E value, and γ‐tocopherol, which contributes to oil stability. The objective of this research was to select for contrasting tocopherol content and profile in Ethiopian mustard (Brassica carinata A. Braun). A collection of 211 F4:5 lines was evaluated for tocopherol content and profile, and divergent selection was conducted till the S3:4 generation. Selection resulted in two lines with increased tocopherol content (244 and 243 mg/kg seed as average of four environments), one line with reduced tocopherol content (117 mg/kg), two lines with reduced α/γ‐tocopherol ratio (0.22 and 0.28) and two lines with increased α/γ‐tocopherol ratio (3.74 and 3.34). Control line C‐101 averaged 196 mg/kg with α/γ‐tocopherol ratio of 1.10. Reduced α/γ‐tocopherol ratio was controlled by recessive alleles at a single locus. Seed to plant correlation was high (r = 0.92), which suggests the feasibility of selecting at the single‐seed level.  相似文献   
86.
ObjectiveTo compare tidal volume estimations obtained from Respiratory Ultrasonic Plethysmography (RUP) with simultaneous spirometric measurements in anaesthetized, mechanically ventilated horses.Study designProspective randomized experimental study.AnimalsFive experimental horses.MethodsFive horses were anaesthetized twice (1 week apart) in random order in lateral and in dorsal recumbency. Nine ventilation modes (treatments) were scheduled in random order (each lasting 4 minutes) applying combinations of different tidal volumes (8, 10, 12 mL kg?1) and positive end-expiratory pressures (PEEP) (0, 10, 20 cm H2O). Baseline ventilation mode (tidal volume = 15 mL kg?1, PEEP = 0 cm H2O) was applied for 4 minutes between all treatments. Spirometry and RUP data were downloaded to personal computers. Linear regression analyses (RUP versus spirometric tidal volume) were performed using different subsets of data. Additonally RUP was calibrated against spirometry using a regression equation for all RUP signal values (thoracic, abdominal and combined) with all data collectively and also by an individually determined best regression equation (highest R2) for each experiment (horse versus recumbency) separately. Agreement between methods was assessed with Bland-Altman analyses.ResultsThe highest correlation of RUP and spirometric tidal volume (R2 = 0.81) was found with the combined RUP signal in horses in lateral recumbency and ventilated without PEEP. The bias ± 2 SD was 0 ± 2.66 L when RUP was calibrated for collective data, but decreased to 0 ± 0.87 L when RUP was calibrated with individual data.Conclusions and clinical relevanceA possible use of RUP for tidal volume measurement during IPPV needs individual calibration to obtain limits of agreement within ± 20%.  相似文献   
87.
We used a spatially explicit model of forest dynamics, supported by empirical field data and socioeconomic data, to examine the impacts of human disturbances on a protected forest landscape in Kyrgyzstan. Local use of 27 fruit and nut species was recorded and modeled. Results indicated that in the presence of fuelwood cutting with or without grazing, species of high socioeconomic importance such as Juglans regia, Malus spp., and Armeniaca vulgaris were largely eliminated from the landscape after 50–150 yr. In the absence of disturbance or in the presence of grazing only, decline of these species occurred at a much lower rate, owing to competitive interactions between tree species. This suggests that the current intensity of fuelwood harvesting is not sustainable. Conversely, current grazing intensities were found to have relatively little impact on forest structure and composition, and could potentially play a positive role in supporting regeneration of tree species. These results indicate that both positive and negative impacts on biodiversity can arise from human populations living within a protected area. Potentially, these could be reconciled through the development of participatory approaches to conservation management within this reserve, to ensure the maintenance of its high conservation value while meeting human needs.  相似文献   
88.
Small ruminant lentiviruses infect sheep and goats worldwide, causing chronic progressive diseases and relevant economic losses. Disease eradication and prevention is mostly based on serological testing. The goal of this research was to investigate the presence of the small ruminant lentiviruses (SRLVs) in Jordan and to characterize the serological response in sheep and goat populations. A panel of sera were collected from flocks located in Northern Jordan and Jordan Valley. The samples were tested using three ELISA assays: a commercially available ELISA based on p25 recombinant protein and transmembrane peptide derived from British maedi–visna virus (MVV) EV1 strain, an ELISA based on P16-P25 recombinant protein derived from two Italian strains representative of MVV- and caprine arthritis encephalitis virus (CAEV)-like SRLVs, and an ELISA based on SU5 peptide from the same two Italian isolates. The results indicate that both MVV- and CAEV-like strains are present in Jordan and that the majority of the viruses circulating among sheep and goat populations belong to the MVV-like genotype.  相似文献   
89.
Abstract

A DNA vaccine containing the glycoprotein (G) gene of the North American viral hemorrhagic septicemia virus (VHSV) genotype IVb was developed to evaluate the immune response of fish following vaccination and evaluate its efficacy in protecting a susceptible species, the Muskellunge Esox masquinongy, against VHSV-IVb challenge. Seven weeks (539 degree-days) following vaccination with 10 μg of either pVHSivb-G or a control plasmid, Muskellunge were challenged by immersion with 105 plaque-forming units (pfu)/mL of VHSV-IVb. Fish vaccinated with pVHSivb-G had a relative percent survival (RPS) of 45%. Vaccinated fish also had significantly lower mean viral titers in tissues (4.2 × 102 pfu/g) and viral prevalence (4%) than fish receiving the plasmid control vaccine (3.3 × 105 pfu/g; 82%). Neutralizing antibodies were detected 28 d (308 degree-days) postchallenge (11 weeks postvaccination) in 100% of Muskellunge vaccinated with pVHSivb-G compared with only 12% of plasmid-control-vaccinated Muskellunge, suggesting robust induction of a secondary, adaptive immune response. In addition, pVHSivb-G–vaccinated Rainbow Trout Oncorhynchus mykiss challenged 7 d (100 degree-days) postvaccination with the heterologous novirhabdovirus, infectious hematopoietic necrosis virus (IHNV), experienced an RPS of 61%, compared to control fish, suggesting induction of an early and transient nonspecific antiviral immune response. This study provides an important starting point for VHSV-IVb vaccine development and useful information about the antiviral immune response elicited by DNA vaccination in a nondomesticated fish species.

Received May 1, 2016; accepted September 1, 2016  相似文献   
90.
High fibre breads were produced adding durum wheat bran fractions of different composition and particle size. Fresh products were characterized for texture, crumb grain, volume, colour, water status (water activity, moisture content, frozen water content, 1H molecular mobility).  相似文献   
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