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1.
Overweight and obesity are multifactorial diseases caused by an imbalance in energy metabolism. An underlying genetic predisposition is often a factor in these conditions. In the cat breeding family of the Institute of Animal Nutrition at the Vetsuisse Faculty, University of Zurich, a segregating overweight phenotype with a genetic contribution was observed. From this breeding family, 26 kittens were followed from birth up to 8 months of age. During this time, food intake was measured using an automatic feeding station, and energy expenditure was investigated using indirect calorimetry at the ages of 4 and 6 months. Dual‐energy X‐ray absorptiometry (DEXA) was performed and blood glucose, leptin and insulin were measured at the ages of 4, 6 and 8 months. The kittens were also weighed daily for the first 2 weeks of life, every second day until weaning and once per week until 8 months of age. The body condition score (BCS) was evaluated monthly between 2 and 8 months of age. The main finding of this study is that a predisposition to overweight is connected to a higher food intake early in life, with no significant alterations in energy expenditure. The leptin blood levels were related to body fat percentage, and insulin sensitivity did not seem to be affected.  相似文献   
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Fossil fuel-derived inputs can increase cow-calf production per unit of land or labor but can raise financial and environmental concerns. Eleven US cow-calf systems from nine ecological regions in Iowa, South Dakota, Tennessee, and Texas were analyzed to determine quantities of energy used and carbon (C) emitted due to fossil fuel use (excluding emissions from soils and biota) and to determine how management and environment influenced those quantities. Total energy and C cost, calculated cow?1 or ha?1, were highly correlated (0.99). Energy use cow?1 and ha?1 varied greatly across systems, ranging from 3 000 to 12 600 megajoules (MJ) · cow?1 · yr?1 and from 260 to 20 800 MJ · ha?1 · yr?1. As stocking rate increased, MJ · cow?1 increased at an increasing rate. Differences in quantity of fertilizer accounted for most variation in energy use. Fertilizer allowed higher stocking rates but reduced energy efficiency of liveweight marketed. Compared to intensive, higher stocking rate systems, rangeland systems based on native or naturalized forages used little or no fertilizer, but used more energy cow?1 for crude protein (CP) supplementation, fencing, and pickup trucks. Across all systems, energy used to produce winter feed ranged from 0% to 46% of total energy. Northern systems used higher percentages of total energy for winter feed and fed for more days year?1, but southern systems that included large amounts of bermudagrass (Cynodon dactylon L.) hay used the most MJ · cow?1 for winter feed. Systems with high MJ · cow?1 were vulnerable to shocks in energy prices. Reducing energy use and C emissions from cow-calf operations is possible, especially by reducing fertilizer and hay use, but would likely reduce productivity ha?1. Forages with high nitrogen use efficiency, locally adapted plants and animals, and replacement of hay with unfertilized dormant forage and CP supplementation could reduce energy use.  相似文献   
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Plant Foods for Human Nutrition - Herbal teas are used as therapeutic vehicles in many forms of traditional medicine and are a popular global beverage. The purpose of this scoping review was to...  相似文献   
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Trace element fingerprints were deciphered for wines from Canada's two major wine-producing regions, the Okanagan Valley and the Niagara Peninsula, for the purpose of examining differences in wine element composition with region of origin and identifying elements important to determining provenance. Analysis by ICP-MS allowed simultaneous determination of 34 trace elements in wine (Li, Be, Mg, Al, P, Cl, Ca, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Mo, Ag, Cd, Sb, I, Cs, Ba, La, Ce, Tl, Pb, Bi, Th, and U) at low levels of detection, and patterns in trace element concentrations were deciphered by multivariate statistical analysis. The two regions were discriminated with 100% accuracy using 10 of these elements. Differences in soil chemistry between the Niagara and Okanagan vineyards were evident, without a good correlation between soil and wine composition. The element Sr was found to be a good indicator of provenance and has been reported in fingerprinting studies of other regions.  相似文献   
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We evaluated phenotypic markers in full-genome sequences of avian influenza isolates to identify avian strains with increased potential for transmission and pathogenicity in mammals. Of 149 markers examined, 67 were positive in the consensus sequences from 206 avian isolates. Analysis of deep sequencing data in a subset of 24 isolates revealed that 344 subpopulations occurred at marker positions. Markers in subpopulations were significantly more likely to be negative (258/344) than positive (86/344), but nearly all of the marker-positive subpopulations (78/86) were associated with marker-negative consensus sequences. Our analysis revealed significant variation in important markers among avian isolates, and showed that consensus sequences do not fully convey an isolate's potential for increased transmissibility and pathogenicity in mammals.  相似文献   
7.

Background

Avian influenza virus (AIV) subtypes H5 and H7 attracts particular attention because of the risk of their potential pathogenicity in poultry. The haemagglutination inhibition (HI) test is widely used as subtype specific test for serological diagnostics despite the laborious nature of this method. However, enzyme-linked immunosorbent assays (ELISAs) are being explored as an alternative test method.H5 and H7 specific monoclonal antibodies were experimentally raised and used in the development of inhibition ELISAs for detection of serological response specifically directed against AIV subtypes H5 and H7. The ELISAs were evaluated with polyclonal chicken anti-AIV antibodies against AIV subtypes: H1N2, H5N2, H5N7, H7N1, H7N7, H9N9, H10N4 and H16N3.

Results

Both the H5 and H7 ELISA proved to have a high sensitivity and specificity and the ELISAs detected H5 and H7 antibodies earlier during experimental infection than the HI test did. The reproducibility of the ELISA’s performed at different times was high with Pearson correlation coefficients of 0.96-0.98.

Conclusions

The ELISAs are a potential alternative to the HI test for screening of large amounts of avian sera, although only experimental sera were tested in this study.  相似文献   
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This study integrated physical, chemical, and molecular techniques to assess relationships between soil bacterial community structures and the quantity and quality of soil organic carbon (SOC) at the soil microenvironment scale (e.g., within different aggregate size-fractions). To accomplish this goal, soil samples (0–5 cm) were collected from the Texas High Plains region under a variety of dryland and irrigated cropping systems. The soil was separated into macroaggregates, microaggregates, and silt + clay fractions that were analyzed for (1) bacterial diversity via pyrosequencing of the 16s rRNA gene and (2) SOC quantity and quality using a combustion method and mid-infrared diffuse reflectance spectroscopy (mid-IR), respectively. Results from pyrosequencing showed that each soil microenvironment supported a distinct bacterial community. Similarly, mid-IR data revealed distinct spectral features indicating that these fractions were also distinguished by organic and mineral composition. Macroaggregates showed relatively high abundance of Actinobacteria (excluding order Rubrobacteriales) and α-Proteobacteria and contained the most SOC. Microaggregates showed high relative abundance of Rubrobacteriales and the least amount of SOC. Predominance within the soil microenvironment and correlations along the mid-IR spectra were different between members of the order Rubrobacteriales compared with all other members of the Actinobacteria phyla, suggesting they have different ecological niches. Mid-IR results revealed microaggregates had greater absorbance in the 1370–1450 cm?1 region for phenolic and alkyl groups (possibly recalcitrant C). Silt + clay fractions were distinguished by Gemmatimonadetes and OP10 phyla, which positively correlated with spectral absorption in the1250–1150 cm?1 range (indicating both degradable and recalcitrant C forms). In contrast to general diversity index measurements, distributions of the more rare bacterial phyla (phyla representing <6% of the identified population) were more important for differentiating between communities in soil microenvironments. To our knowledge, this is the first study to investigate soil bacterial communities among soil aggregates using pyrosequenging and to associate these communities to specific soil C chemistries as indicated by mid-IR absorbance.  相似文献   
9.
低碳氮比对蛋鸡粪与蔗渣好氧堆肥的影响   总被引:2,自引:0,他引:2  
通过对低碳氮比(C/N)的蛋鸡粪与蔗渣好氧堆肥研究,旨在探讨充分利用蔗渣资源开展蛋鸡粪资源化利用的现实性与可行性.试验将蛋鸡粪与蔗渣混合制成C/N比值分别为17.88和13.94的两个处理组,好氧堆肥,测定6周堆肥过程中堆体温度、物料C/N、水溶性碳、水溶性氮、铵态氮、硝态氮、全钾、总磷含量的变化.结果表明:2个堆体温度都能快速升至50℃以上,并维持3周,但C/N 17.88组更快升至60℃并在此温度维持时间较长,同时加快了物料铵态氮向硝态氮转化,相对缩短了物料腐熟时间;C/N 13.94组铵态氮较高,pH值也高,N素损失较多,延长了腐熟时间;蔗渣可导致堆肥物料可利用碳少.分析表明,在减少N素损失和提高蔗渣降解率的措施下,低C/N的蛋鸡粪与蔗渣好氧堆肥在生产上具可行性.  相似文献   
10.
It is widely accepted that the commensal gut microbiota contributes to the health and well-being of its host. The solitary tunicate Ciona intestinalis emerges as a model organism for studying host–microbe interactions taking place in the gut, however, the potential of its gut-associated microbiota for marine biodiscovery remains unexploited. In this study, we set out to investigate the diversity, chemical space, and pharmacological potential of the gut-associated microbiota of C. intestinalis collected from the Baltic and North Seas. In a culture-based approach, we isolated 61 bacterial and 40 fungal strains affiliated to 33 different microbial genera, indicating a rich and diverse gut microbiota dominated by Gammaproteobacteria. In vitro screening of the crude microbial extracts indicated their antibacterial (64% of extracts), anticancer (22%), and/or antifungal (11%) potential. Nine microbial crude extracts were prioritized for in-depth metabolome mining by a bioactivity- and chemical diversity-based selection procedure. UPLC-MS/MS-based metabolomics combining automated (feature-based molecular networking and in silico dereplication) and manual approaches significantly improved the annotation rates. A high chemical diversity was detected where peptides and polyketides were the predominant classes. Many compounds remained unknown, including two putatively novel lipopeptides produced by a Trichoderma sp. strain. This is the first study assessing the chemical and pharmacological profile of the cultivable gut microbiota of C. intestinalis.  相似文献   
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