Chemical and nutritional value of organic feedstuffs: a need to address in monogastric feeding

As it is mandatory since January 2019 to feed organic pigs and poultry with 100% organic feeds in the EU, abetter knowledge of the nutritional value of organic raw materials is, more than ever, a key for farmers to develop efficient nutrition systems for organic livestock farming. Studies are being conducted in the French CASDAR programme SECALIBIO to compare organic raw materials to conventional ones, to establish the composition and nutritional value of organic feeds, and to evaluate their variability. A database of 6,577 samples of 94 organic raw materials, most of them commonly used in monogastric feeding (soybean meals, maize, faba bean, etc.), was constituted using data from the French Feed Database of the AFZ, from previous research programmes and from feed companies participating in SECALIBIO. In vivo digestibility trials on pigs and poultry were conducted to evaluate the specificities of organic raw materials and provide new data (for forage peas for example). The variability of organic raw materials was generally comparable to that of conventional ones. However, the fat content of organic sunflower (6.2 to 25.2% MS) and soybean (5.37 to 22.6% MS) meals varied a lot due to processing technologies, and it was suggested to delineate categories with consistent crude protein and fibre content. In connection with it, for poultry, the digestibility of protein could vary a lot for sunflower (76.5-83.0%) and soybean (74.4-87.32%) meals. Organic soybean meals was reported to have a lower lysine/crude protein ratio than the conventional one (5.75 vs 6.14%): further investigations will determine the impact of this difference on feed formulation. The first practical result of this study will be the creation of specific tables of composition and nutritional value of organic feeds for pigs and poultry which represents a key for farmers to develop an efficient nutrition system in organic farming.