In practice, there are various ways to influence ammonia and odor emissions from fattening poultry. Be it on the one hand by reducing the protein or by using alternative protein sources, or on the other hand by adding additives in the context of feed production or use.
Before the widespread use of alternative protein sources, additives or protein-reduced feed in practice, the poultry industry needs reliable knowledge about the effects of the components used. This applies to the expected fattening performance (daily gain, final fattening weight, feed conversion), the possible release of harmful gases (ammonia and carbon dioxide) and the extent of odor emissions. Under no circumstances can the goal be to place potentially emission-reducing feed on the market, which, although it contributes to reducing ammonia and odor from poultry farming, in return reduces the expected fattening performance and counteracts economic success.
At the HBLFA Raumberg-Gumpenstein, two identical stables (each for 420 fattening animals) are available for direct comparisons of experimental and control feed. In each compartment, the air rates, temperature and humidity as well as the harmful gas levels in the animal area and in the exhaust air unit are permanently recorded using photoacoustic spectroscopy; At 7-day intervals, additional air samples are taken for olfactometry (odor measurement). Continuous automatic weighing, recording of the amounts of feed used as well as water consumption and failures during a fattening cycle complete the logging.
Currently, in Raumberg-Gumpenstein, as part of a company cooperation, a four-phase experimental feed with a reduced crude protein content is being compared to a conventional four-phase fattening feed. In the subsequent studies at the end of 2020, the effects of a plant-based feed additive will be examined more closely in experimental terms.
