Feed efficiencies in animal production: A non-numerical analysis

Abstract

More and more, animal production is questioned, not only by animal welfare organizations or vegans, but also in the context of climate change. Some even say that animals are the number one greenhouse gas emitters, not only directly (e.g. ruminants), but also indirectly by land use change, especially in South America. Others say that animals are a very inefficient way of food production, since feed conversion always means a certain loss. From a food production point of view, animal production can be divided into three groups. The first one is the group of extensive grazers. Since only a small percentage of the land surface is arable land, herbivores (especially ruminants) are the only way to produce on - from an anthropocentric point of view - 'useless' grounds. Also, one billion poor people in those regions are depending on animals for food, manure, draught or as 'living bank' in those harsh conditions. Animals are thus necessary to survive and everything produced by them can be seen as a net gain, increasing the land use efficiency. Secondly, animals can be used as converters of crop residues, especially meals from vegetable oil production for human consumption, chemistry or biofuels. Animals, especially ruminants, are very efficient in recycling energy and proteins which are not digestible or wanted as food by humans (or other animals). Probably, second generation biofuels shall replace at least for some part the use of animals as converters, depending on economics or policy. To balance the animals' diet, also grains are needed to make sure the animals stay healthy. If you look at feed efficiency in this way, efficiency ratios for different animal species differ from the traditional feed conversion and for some species animal production even means an efficiency gain. The third group is the surplus group. Those animals are produced not because they use 'useless' land or energy and proteins, but because some people are wealthy enough to feed them with edible products. Although some of them have the best feed conversion ratios, this group of (mostly monogastric) animals produces animal products in an inefficient way from a human-animal-competition or ecological point of view. Only this group of animals could be considered as ethically problematic. It will become a pressing issue because of the increasing demand from upcoming economies for animal luxury products.