Environmental and Nutritional Benefits of Biopreservation of Animal Feed

Biopreservation of moist animal feed provides an alternative to conventional conservation methods and is often beside of saving energy and antimicrobial chemicals a way to improve feed quality. In regions with temperate climate drying of cereal grains can require approximately 60% of the total energy input during plant husbandry. In tropical regions, drying can be incomplete due to high air humidity and improper handling of the material, resulting in a risk for contamination with mycotoxine forming moulds or pathogenic microorganisms. Microbial enzyme activities on feed and activation of intrinsic enzymes in plant material stored wet, increase the bioavalability of minerals and nutrients. For instance phytases can decrease the phytate content. Phytate is the main phosphate storage molecule in plants. It is only partially degraded in non-ruminants, resulting in phosphate release and eutrophication of water environments. Phytate is also an antinutrient, binding minerals and proteins and its degradation will improve the bioavailability of those substances. Biopreservation biomass can also be a locally produced protein source, which can replace soya. Soya production is frequently associated with negative environmental and socioeconomic consequences, and its worldwide trading requires energy for transport and handling. Translocation of nutrients between countries also precludes nutrient recirculation on arable land. Biopreservation often relies on spontaneous microbial developments, thus storage stability, feed hygiene, palatability and nutritional value may vary depending on the microbial composition. Microbial populations in feed are often monitored by traditional plate counting methods, but species identification of isolates demonstrated substantial changes in microbial populations even when plate counting indicated a stable flora. From economical, environmental and animal welfare perspectives it is of great interest to obtain a stable and predictable microbial population in the feed, which can be achieved by developing starter cultures.