1,405 research outputs found
Potential food production from forage legume-based-systems in Europe: an overview
peer-reviewedIntensification of EU livestock farming systems has been accompanied by the development of maize silage and intensively fertilised grasses at the expense of forage
legume crops. However in the new context of agriculture, the development of forage
legumes constitutes one of the pillars for future livestock farming systems with high
environmental and economical performances. Yield benefits of grass-clover mixtures
are equivalent fertiliser N inputs of 150 to 350 kg/ha, and productive grass-clover
mixtures can fix 100 to 380 kg N per hectare symbiotically from the atmosphere.
Animal intake of legumes is high and the rate of decline of legume nutritional
quality with advancing maturity is less than for grasses, especially in the case of
white clover, which makes mixed pastures easier to manage. Animal performances
at grazing are identical or higher on clover-enriched pastures. Due to their high
protein concentration, conserved forage legumes fit well with maize silage. Forage
legumes increase the concentration of beneficial α-linolenic acid in ruminant products.
Environmental balance of forage legumes is positive. Increasing the proportion
of white clover at the expense of mineral N fertilisation can reduce the risk of
nitrate leaching. Because forage legumes only require solar energy to fix N from the
air, they also reduce energy consumption and associated impacts. They contribute
to reduce the global warming potential of livestock systems by reducing emission
of enteric methane and nitrous oxide from pasture and crop production. As an
element of arable crop rotations, grass-clover leys suppress pests, diseases and
weeds, improve soil structure and prevent soil erosion and nitrate leaching.
Nevertheless, forage legumes have some limitations: expensive to harvest, difficulties of conservation, management of the associations. To take full advantage of forage legumes in the future, new research and development are required as well as financial support from the EU
Strongly magnetized classical plasma models
Discrete particle processes in the presence of a strong external magnetic field were investigated. These processes include equations of state and other equilibrium thermodynamic relations, thermal relaxation phenomena, transport properties, and microscopic statistical fluctuations in such quantities as the electric field and the charge density. Results from the equilibrium statistical mechanics of two-dimensional plasmas are discussed, along with nonequilibrium statistical mechanics of the electrostatic guiding-center plasma (a two-dimensional plasma model)
Multi-locus sequence typing for phylogeny and fine typing of Mycoplasma agalactiae strains
Contagious Caprine Pleuropneumonia cELISA validation : Vaccine quality assurance prevalence studies
Modified Debye-Huckel Electron Shielding and Penetration Factor
Screened potential, modified by non standard electron cloud distributions
responsible for the shielding effect on fusion of reacting nuclei in
astrophysical plasmas, is derived. The case of clouds with depleted tails in
space coordinates is discussed. The modified screened potential is obtained
both from statistical mechanics arguments based on fluctuations of the inverse
of the Debye-Huckel radius and from the solution of a Bernoulli equation used
in generalized statistical mechanics. Plots and tables useful in evaluating
penetration probability at any energy are provided.Comment: 9 pages, 3 figures, 3 table
Research methodology of grazing
Throughout Europe, grass is the main feed for dairy cattle. This report presents the main results of the first meeting of the European Grassland Federation (EGF) Working Group Grazing in Kiel on 29 August 2010. The theme of the meeting was "Research methodology of grazing". There were three sessions: - setting the scene; - modelling of grazing; and - field measurements
Recommended from our members
Potential of legume-based grassland-livestock systems in Europe
European grassland-based livestock production systems
face the challenge of producing more meat and
milk to meet increasing world demands and to achieve
this using fewer resources. Legumes offer great potential
for achieving these objectives. They have numerous
features that can act together at different stages in
the soil–plant–animal–atmosphere system, and these
are most effective in mixed swards with a legume proportion
of 30–50%. The resulting benefits include
reduced dependence on fossil energy and industrial
N-fertilizer, lower quantities of harmful emissions to
the environment (greenhouse gases and nitrate), lower
production costs, higher productivity and increased
protein self-sufficiency. Some legume species offer
opportunities for improving animal health with less
medication, due to the presence of bioactive secondary
metabolites. In addition, legumes may offer an adaptation
option to rising atmospheric CO2 concentrations
and climate change. Legumes generate these benefits
at the level of the managed land-area unit and also at
the level of the final product unit. However, legumes
suffer from some limitations, and suggestions are made
for future research to exploit more fully the opportunities
that legumes can offer. In conclusion, the development
of legume-based grassland–livestock systems
undoubtedly constitutes one of the pillars for more
sustainable and competitive ruminant production systems,
and it can be expected that forage legumes will
become more important in the future
Towards a better definition of the immuno-proteome in the frame of contagious or vector-borne animal diseases
Defining the repertoire of antigenic targets is central to better understanding the immune responses against wether contagious pathogens and those transmitted by arthropod vectors. Traditional molecular approaches of antigen discovery have identified many immunodominant antigens, but they afford limited proteome coverage. Advances in proteomic technologies that are based on peptide library and the increase in genome sequencing that enriched molecular databases, allowed the definition of new analytical strategies with interrogation of the entire proteome for antigens. At the same time, improved technologies for antibodies purification for serum as well as antigens immunocapture lead scientists to revisiting the characterisation of immuno-proteomes, particularly in the frame of contagious or vector-borne animal diseases. Here, we propose an analytical workflow to illustrate how to deepen the definition of the immuno-proteomes, and illustrate the proof of concept targeting Mycoplasma mycoïdes, the causative agent of contagious bovine pleuropneumonia (CBPP). (Résumé d'auteur
Differential impact of milk fatty acid profiles on cardiovascular risk biomarkers in healthy men and women
International audienceObjectives: to evaluate the impact of three specific ruminant (R) milk fats resulting from modification of the cow's diet on cardiovascular risk factors in healthy volunteers. R-milk fats were characterized by increased content in total trans fatty acids (R-TFA) and parallel decrease in saturated fatty acids (SFA). Methods: 111 healthy, normolipemic men and women have been recruited for a monocentric, randomised, double-blind, and parallel intervention, 4-week controlled study. Volunteers consumed 3 experimental products (butter, dessert cream and cookies) made with one of the 3 specific milk fats (55 g fat/day). During the first week (run-in period), the subjects consumed on a daily basis dairy products containing 72% SFA/2.85% R-TFA (called "L0"). For the next 3 weeks of the study (intervention period), the first group continued to consume L0 products. The second group received dairy products containing 63.3% SFA/4.06% R-TFA (called "L4"), and the third group received dairy products containing 56.6% SFA/12.16% R-TFA (called "L9"). Results: plasma concentrations of HDL-cholesterol was not significantly altered by either diet (p = 0.38). Compared to L0 diet, L4 diet contributed to reduce LDL-cholesterol (-0.140.38 mmol/L, p= 0.04), total cholesterol (-0.130.50 mmol/L, p = 0.04), LDL-cholesterol/HDL-cholesterol (-0.140.36, p = 0.03) and total cholesterol/HDL-cholesterol (-0.180.44, p = 0.02). Conclusion: different milk fat profiles can change cardiovascular plasma parameters in human healthy volunteers. A limited increase of the R-TFA/SFA ratio in dairy products is associated with an improvement in some cardiovascular risk factors. However, a further increase in R-TFA/SFA ratio has no additional benefit
The profile of a narrow line after single scattering by Maxwellian electrons: relativistic corrections to the kernel of the integral kinetic equation
The frequency distribution of photons in frequency that results from single
Compton scattering of monochromatic radiation on thermal electrons is derived
in the mildly relativistic limit. Algebraic expressions are given for (1) the
photon redistribution function, K(nu,Omega -> nu',Omega'), and (2) the spectrum
produced in the case of isotropic incident radiation, P(nu -> nu'). The former
is a good approximation for electron temperatures kT_e < 25 keV and photon
energies hnu < 50 keV, and the latter is applicable when hnu(hnu/m_ec^2) < kT_e
< 25 keV, hnu < 50 keV. Both formulae can be used for describing the profiles
of X-ray and low-frequency lines upon scattering in hot, optically thin
plasmas, such as present in clusters of galaxies, in the coronae of accretion
disks in X-ray binaries and AGNs, during supernova explosions, etc. Both
formulae can also be employed as the kernels of the corresponding integral
kinetic equations (direction-dependent and isotropic) in the general problem of
Comptonization on thermal electrons. The K(nu,Omega -> nu',Omega') kernel, in
particular, is applicable to the problem of induced Compton interaction of
anisotropic low-frequency radiation of high brightness temperature with free
electrons in the vicinity of powerful radiosources and masers.
Fokker-Planck-type expansion (up to fourth order) of the integral kinetic
equation with the P(nu -> nu') kernel derived here leads to a generalization of
the Kompaneets equation. We further present (1) a simpler kernel that is
necessary and sufficient to derive the Kompaneets equation and (2) an
expression for the angular function for Compton scattering in a hot plasma,
which includes temperature and photon energy corrections to the Rayleigh
angular function.Comment: 29 pages, 17 figures, accepted for publication in ApJ, uses
emulateapj.sty, corrects misprints in previous astro-ph versio
- …
