49 research outputs found
Natural feed additives as alternative to in-feed medication
The use of antibiotics in livestock production is very common and widespread. The reason for their use can be very diverse. Examples are the treatment of clinically sick animals, the improvement of growth performance, as well as the prevention of common bacterial infections. However, the extensive use of such antimicrobials raised concerns of increasing the incidence of resistant pathogenic bacteria, which has a negative impact not only on livestock production, but also on human health. In the last years, many different substances have been investigated as suitable alternatives to the use of antibiotics as growth promoting agents and as prophylactic substances
Herschel-ATLAS: Multi-wavelength SEDs and physical properties of 250 micron-selected galaxies at z < 0.5
We present a pan-chromatic analysis of an unprecedented sample of 1402 250
micron-selected galaxies at z < 0.5 (mean z = 0.24) from the Herschel-ATLAS
survey. We complement our Herschel 100-500 micron data with UV-K-band
photometry from the Galaxy And Mass Assembly (GAMA) survey and apply the
MAGPHYS energy-balance technique to produce pan-chromatic SEDs for a
representative sample of 250 micron selected galaxies spanning the most recent
5 Gyr of cosmic history. We derive estimates of physical parameters, including
star formation rates, stellar masses, dust masses and infrared luminosities.
The typical H-ATLAS galaxy at z < 0.5 has a far-infrared luminosity in the
range 10^10 - 10^12 Lsolar (SFR: 1-50 Msolar/yr) thus is broadly representative
of normal star forming galaxies over this redshift range. We show that 250
micron-selected galaxies contain a larger mass of dust at a given infra-red
luminosity or star formation rate than previous samples selected at 60 micron
from IRAS. We derive typical SEDs for H-ATLAS galaxies, and show that the
emergent SED shape is most sensitive to specific star formation rate. The
optical-UV SEDs also become more reddened due to dust at higher redshifts. Our
template SEDs are significantly cooler than existing infra-red templates. They
may therefore be most appropriate for inferring total IR luminosities from
moderate redshift submillimetre selected samples and for inclusion in models of
the lower redshift submillimetre galaxy populations.Comment: 26 pages, 24 figures, Accepted by MNRA
Natural feed additives as alternative to in-feed medication
The use of antibiotics in livestock production is very common and widespread. The reason for their use can be very diverse. Examples are the treatment of clinically sick animals, the improvement of growth performance, as well as the prevention of common bacterial infections. However, the extensive use of such antimicrobials raised concerns of increasing the incidence of resistant pathogenic bacteria, which has a negative impact not only on livestock production, but also on human health. In the last years, many different substances have been investigated as suitable alternatives to the use of antibiotics as growth promoting agents and as prophylactic substances.</p