In SOLID, WP3, a desk-top review was conducted: The overview of the literature demonstrates a wide variation in the potential novel and underutilized feed resources to be used in organic and low input dairy systems, and in many cases also the lack of scientific knowledge which may prevent the efficient use of some feeds.
By Marketta Rinne, MTT Agrifood Research, Finland, WP3
Innovative use of novel and underutilized feed resources has the potential to improve the efficiency of the “green economy” by finding the most relevant uses for different biomass fractions in synergy between agriculture, bioenergy production and other industries. By-products from agricultural, forestry, food processing and bioenergy sectors can be considered sustainable sources of additional feeds in forage based dairy diets, and agro-forestry systems may provide additional roughage.
Increasing demand of processed organic foods for human consumption gives rise to the availability of organically labelled by-products. This may broaden the feed supply for
organic livestock and increase supply of organic milk. The possibility to use the by-products as organic feedstuffs should also increase their economic value compared to
alternative uses such as consumption as conventional feedstuffs or in bioenergy production.
There is a feed for every need
The overview of the literature demonstrates a wide variation in the potential novel and underutilized feed resources to be used in organic and low input dairy systems, and in many cases also the lack of scientific knowledge which may prevent the efficient use of some feeds. The variation is caused by the diversity of the raw materials and variability in raw material composition, which are further diversified by the processing technologies applied.
The variability in the feed materials may provide opportunities to find suitable supplements in terms of e.g. energy, protein and mineral concentrations to various situations depending on the type of animals and basal feeding.
By-product feeds often have a high moisture content and transportation and/or preservation may significantly increase the cost of the feeds, emphasizing the importance
of logistics. Preservation also plays an important role in ensuring safety of the whole food-production chain. Meals from various oilseeds such as Camelina, Crambe, Safflower and rapeseed provide protein rich supplements after oil extraction. Production of them on-farm could offer a good opportunity to increase supply of oils either for human consumption or biodiesel production, to produce high quality protein supplements for animals and to improve farm economy.
High-protein and low-fat distillers’ grains are results of sophisticated industrial processes in order to extract as much as possible from the cereals (e.g. oil) and to diversify and add value to their by-products in order to meet the farmers’ requests (e.g. the case of high-protein distillers’ grains).
By-products from the pulse industry are good sources of protein. Legumes are also able to fix nitrogen from the atmosphere giving them an essential role in the nitrogen supply to the organic farming. The minor species (buckwheat, mustard and Canary seed) are scarcely characterized from a nutritional point of view although they may have significance as local feed resources.
Olive leaves and cakes are by-products from olive oil production, and if adequately supplemented, they may be successfully used in animal diets. Tomato wastes offer a
cheap source of energy and protein with high digestibility; however, the high moisture content makes the processing and storing challenging.
Carbohydrates from wood are available in large quantities, but because of very low digestibility of intact wood, heavy processing is required to improve their digestibility.
The unpredictability and variability of the feed supply from agro-forestry systems is a challenges to their use, but fast growing trees provide the potential for a large quantity of
material. Valorisation of the silvopastoral systems requires a change in the mindset of the farmer. Harvesting, preservation and transportation questions also need to be solved for agro-forestry based systems before they can be adopted in wider use.
Research can support the use of novel feeds
The amount and quality of feeds offered to animals have significant effects on feed intake and milk production, which largely dictates the economics of production, but they may also influence milk quality and health of the animals. This review was unable to draw any clear-cut conclusions on the latter because of lack of information and large variability among and within feed materials reviewed.
If the feeds contain some bioactive compounds such as tannins or salicylic acid in fodder trees, or some harmful substances or residues, substantial responses can sometimes occur in animal health or product quality. The key issue in controlling the potential positive or negative effects on product quality and animal health is to know the chemical composition and concentrations of bioactive compounds in the particular feed material used as well as
their fate in the rumen.
According to EU legislation, the producer of the feed material is responsible for the safety
of the product emphasizing the need of knowledge of potential deleterious effects of feeds.
Strict rules on the acceptability of feeds
Legislation and public opinion set rather strict rules on the acceptability of feeds, particularly in organic but also in low input conventional dairy systems. In some
cases, particularly in adopting truly novel feeding practices such as agro-forestry
systems in intensive temperate production systems, or including novel industrial
by-product feed ingredients, the socio-economic aspects play an important role. The
role of biological research in such cases is to provide reliable information of the feeding value and safety of the new feeding methods.
It is ultimately up to the whole supply-chain, consumers and authorities to decide which new feeding methods will be taken into use. The innovative and conservative approaches need to find a sound balance, and solutions are likely to vary in different regions. A broad-minded approach to valorise novel or under-utilized feed materials may also be valuable in cases of a crisis situation when availability of conventional feeds would be impaired.
In the next phases of WP3 research program, a number of potential feed materials will be subjected to laboratory analyses and in vitro screening.
Finally, some feeds will be chosen for feeding trials both to goats and cows to find out their intake and production potential and effects on milk quality.