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Fermented liquid feed is feed that has been mixed with water at a ratio ranging from 1:1.5 to 1:4. By mixing with water, lactic acid bacteria and yeasts naturally occurring in the feed proliferate and produce lactic acid, acetic acid and ethanol which reduces the pH of the mixture. This reduction in pH inhibits pathogenic organisms from developing in the feed. In addition, when this low pH mixture is fed, it reduces the pH in the stomach of pigs and prevents the proliferation of pathogens such as coliforms and Salmonella in the gastrointestinal tract. For piglets, the use of fermented liquid feed offers the possibility of simultaneously providing feed and water, which may facilitate an easier transition from sow’s milk to solid feed. Secondly, offering properly produced fermented liquid feed may strengthen the role of the stomach as the first line of defense against possible pathogenic infections by lowering the pH in the gastrointestinal tract thereby helping to exclude enteropathogens. Finally, feeding fermented liquid feed to pigs has been shown to improve the performance of suckling pigs, weaner pigs and growing-finishing pigs. In this review, current knowledge about the use of fermented liquid feed in pig diets will be discussed. This will include a discussion of the desirable properties of fermented liquid feed and factors affecting fermentation. In addition, advantages and disadvantages of fermented liquid feed will be discussed including its effects on gastrointestinal health, intestinal pH and the types of bacteria found in the gastrointestinal tract as well as the effects of fermented liquid feeds on pig performance. 相似文献
55.
The time dependence of the orientation of Earth's inner core relative to the mantle was determined using a recently discovered 10-degree tilt in the axis of symmetry of the inner core's seismic-velocity anisotropy. Two methods of analyzing travel-time variations for rays traversing the inner core, on the basis of 29 years of data from the International Seismological Centre (1964-1992), reveal that the inner core appears to rotate about 3 degrees per year faster than the mantle. An anomalous variation in inner-core orientation from 1969 to 1973 coincides in time with a sudden change ("jerk") in the geomagnetic field. 相似文献
56.
Toll‐like receptor and related cytokine mRNA expression in bovine corpora lutea during the oestrous cycle and pregnancy 下载免费PDF全文
JE Gadsby AM Tyson Nipper HA Faircloth M D'Annibale‐Tolhurst J Chang PW Farin IM Sheldon DH Poole 《Reproduction in domestic animals》2017,52(3):495-504
Improving our understanding of the mechanisms controlling the corpus luteum (CL) and its role in regulating the reproductive cycle should lead to improvements in the sustainability of today's global animal industry. The corpus luteum (CL) is a transient endocrine organ composed of a heterogeneous mixture steroidogenic, endothelial and immune cells, and it is becoming clear that immune mechanisms play a key role in CL regulation especially in luteolysis. Toll‐like receptors (TLR) mediate innate immune mechanisms via the production of pro‐inflammatory cytokines, especially within various tissues, although the role of TLR within CL remains unknown. Thus, the objectives of this study were to characterize TLR mRNA expression in the CL during the oestrous cycle and in pregnancy (day 30–50), and to examine the role of TLR signalling in luteal cells. Corpora lutea were collected at various stages of the cycle and pregnancy and analysed for TLR and cytokine mRNA expression. In addition, luteal cells were cultured with the TLR4 ligand (lipopolysaccharide, LPS) for 24 h to evaluate the role of TLR4 in regulating luteal function. Toll‐like receptors 1, 2, 4, 6, tumour necrosis factor alpha (TNF), interferon gamma (IFN‐G), and interleukin (IL)‐12, mRNA expressions were greatest in regressing CL compared with earlier stages (p < .05), whereas no change was observed for IL‐6 mRNA expression. Cytokine mRNA expression in cultured luteal cells was not altered by LPS. Based on these data, one or more of the TLRs found within the CL may play a role in luteolysis, perhaps via pro‐inflammatory cytokine mRNA expression. 相似文献
57.
Higher grain yield and higher grain protein deviation underline the potential of hybrid wheat for a sustainable agriculture 下载免费PDF全文
Patrick Thorwarth Hans P. Piepho Yusheng Zhao Erhard Ebmeyer Johannes Schacht Ralf Schachschneider Ebrahim Kazman Jochen C. Reif Tobias Würschum Carl Friedrich Horst Longin 《Plant Breeding》2018,137(3):326-337
Grain yield and protein content are traits of major importance in wheat breeding, but their combination is challenging due to a tight negative correlation. Protein yield and grain protein deviation have been proposed as selection criteria to simultaneously improve both traits. Sedimentation volume is an indicator of protein quality, which plays an important role for bread‐making quality in wheat. All these traits have been investigated in our study with 135 parental inbred lines, their 1,604 hybrids and 10 commercial check varieties evaluated at five environments. The focus of our study was to investigate the usefulness of the grain protein deviation and to define a bivariate model for calculating the grain protein deviation. Further, we compared line and hybrid wheat for grain yield and quality‐related parameters such as protein content and sedimentation volume. The grain protein deviation determined with a bivariate model delivered robust estimates of variance components and enabled a balanced selection of genotypes with improved protein content and grain yield across different quality classes. Although heterosis for protein content and sedimentation volume was negative, hybrids had a higher grain protein deviation as well as higher grain yield at a given sedimentation volume or a given protein content than line varieties. 相似文献
58.
Solution properties of single-walled carbon nanotubes 总被引:3,自引:0,他引:3
J Chen MA Hamon H Hu Y Chen AM Rao PC Eklund RC Haddon 《Science (New York, N.Y.)》1998,282(5386):95-98
Naked metallic and semiconducting single-walled carbon nanotubes (SWNTs) were dissolved in organic solutions by derivatization with thionychloride and octadecylamine. Both ionic (charge transfer) and covalent solution-phase chemistry with concomitant modulation of the SWNT band structure were demonstrated. Solution-phase near-infrared spectroscopy was used to study the effects of chemical modifications on the band gaps of the SWNTs. Reaction of soluble SWNTs with dichlorocarbene led to functionalization of the nanotube walls. 相似文献
59.
Design of a surface alloy catalyst for steam reforming 总被引:1,自引:0,他引:1
F Besenbacher I Chorkendorff BS Clausen B Hammer AM Molenbroek JK Norskov I Stensgaard 《Science (New York, N.Y.)》1998,279(5358):1913-1915
Detailed studies of elementary chemical processes on well-characterized single crystal surfaces have contributed substantially to the understanding of heterogeneous catalysis. Insight into the structure of surface alloys combined with an understanding of the relation between the surface composition and reactivity is shown to lead directly to new ideas for catalyst design. The feasibility of such an approach is illustrated by the synthesis, characterization, and tests of a high-surface area gold-nickel catalyst for steam reforming. 相似文献
60.
In the year 2002 the breeding initiative Lower Elbe (Züchtungsinitiative Niederelbe, ZIN) was founded with the aim to establish a private financed breeding program of apple cultivars in North Germany. Members of the breeding initiative are fruit farms, the fruit co-operative Marktgemeinschaft Altes Land and some fruit retailers. Breeding work happens in close cooperation with the nursery firm Carolus (Belgium) and the institutes of fruit growing and nursery of the University of Applied Sciences Osnabrück. In the year 2005 selection work in selection step I started. From 2010 12.000 to 14.000 clones will be tested each year. In 2008 the first 24 clones of the selection step II were planted on two locations. Yearly 25 to 50 clones will follow in this selection step. Scientific research projects flank the breeding work. 相似文献