1 Bulletin UASVM Agriculture, 66 (1)/2009 Print ISSN 1843-5246; Electronic ISSN 1843-5386 The Ethical Merits of the Use of By-products in Agriculture Stefan AERTS 1,2 , Ruben BOONEN 2 , Johan DE TAVERNIER 2 , Dirk LIPS 1,2 1 Katholieke Hogeschool Sint-Lieven, Section Agro- and biotechnology, Hospitaalstraat 23, 9100 Sint- Niklaas, Belgium; 2 Boerenbond Chair Agriculture & Society, Centre for Science, Technology and Ethics, Katholieke Universiteit Leuven, Kasteelpark Arenberg 1 – bus 2456, 3001 Leuven, Belgium Stef.Aerts@kahosl.be Abstract. A dramatic gain in efficiency is an absolute necessity if we are to overcome the agricultural challenges of the third millennium. One of the ways that could lead to such a gain in efficiency is a renewed and augmented use of by-products. In an agricultural context the food industry is a major source of potentially valuable by- products. For other Western European countries VALORBIN (2003a) mentions 5 million tons in Denmark, 11 million in The Netherlands, and 14 million tons in Germany. 70 to 80 % of food industry by-products are reused in feed manufacturing. In all applications, two important ethical aspects seem to overarch all others, being (the care for) public health, and the need for recycling. Both aspects will be important with all by-products and all applications, but their relative importance will differ. This does not mean that zero-risk or maximum recycling need to be the goal. In both aspects environmental considerations are included. It is important to keep an eye out for direct and indirect impacts on other products. A hierarchy seems to exists, in which reuse as food has priority over use as feed or biomass (energy or green chemistry), and with a sustained faith as waste as the least preferable option. The by-products that one wants to use in feed production, will have to be selected based on type (e.g. category 3 animal by-products should be safe), traceability (single sourced products are preferred) and goal (e.g. is the target animal omnivorous). Keywords. Ethics, animal by-products, recycling INTRODUCTION In the third millennium, and starting already in the beginning of the 21st century, agriculture is facing some serious challenges. Population growth and climate change are well- known and important issues, but there are many others (energy cost, nature preservation, etc.). It seems that a dramatic gain in efficiency is an absolute necessity if we are to overcome these challenges. One of the ways that could lead to such a gain in efficiency is a renewed and augmented use of by-products of other economic processes. Using such animal and other by- products (rest products, waste products or genuine by-products) as inputs in agricultural processes seems a promising and fruitful way to technical and economical valorisation of such products. On the other hand, the past has already proven that such a recyclation of products in agriculture is not without risks. It is therefore a timely question to explore whether it is indeed possible to reengage in the use of by-products in agriculture (and especially animal production). Based on the situation in Belgium and the EU, this paper will engage in the technical side of this question only shortly, but focus instead on the societal and ethical questions that arise in this context.