From December 2017 onwards, it will not be allowed anymore in the EU to include non-organic protein sources in diets for organic poultry. Moreover, in the EU the use of synthetic amino acids in organic diets is prohibited. The main dietary challenge in European organic egg production is to fulfil the protein requirement, especially the methionine (Met) requirement of the hens. It is concluded that there are options to fulfil the requirement of 100% ingredients of organic origin, but if the practical, economical and foot print issues are taken into account, then the list of options is very small.
Wageningen UR Livestock Research published a review paper in which several strategies to fulfil the EU requirements are discussed. The first strategy is to use protein rich ingredients with a relatively high digestible Met content. High contents of digestible Met often are found in products from animal origin, e.g. casein, fish meal, and milk powder. Although it is allowed to include animal protein sources to diets of monogastrics under tight restrictions, animal proteins cannot be used in feed mills that produce both cattle and poultry feed. This is due to the unavoidable risk of contamination of cattle feed, in which there is a zero-tolerance for animal protein. Therefore, animal protein sources don’t seem to provide the solution for 100% organic laying hen diets, as feed mills only producing poultry feed are quite rare, especially in the organic sector.
In the group of feed ingredients of plant origin, expelled sunflower seed has a relatively high digestible Met content, and this ingredient is also commonly available. Met content of plant ingredients can be increased by selection of high Met varieties and by specifically breeding on high Met content, e.g. by crossing different breeds.
Plant processing techniques might be helpful to concentrate the protein and digestible Met content of ingredients. Applying the dry fractionation technique on legumes and cereals might result in protein concentrates with crude protein contents of at least 50%. A further development of simple separation techniques, which separate the hulls from the other plant fractions, and reduce the fiber content after dehulling, might be helpful to increase the digestible Met content.
Energy dilution of the diet, concomitant with a proportional reduction in other nutrients is an option as well to fulfil the requirement of 100% organic diets. As a consequence, hens have to consume more feed to meet their nutrient requirements.