This Book of Abstracts is the main publication of the 66th Annual Meeting of the European Federation for Animal Science 2015 in Warsaw, Poland. It contains abstracts of the invited papers and contributed presentations. The meeting addressed subjects relating to science and innovation. Important problems were also discussed during the sessions of EAAP's nine Commissions: Animal Genetics, Animal Nutrition, Animal Management and Health, Animal Physiology, Cattle Production, Sheep and Goat Production, Pig Production, Horse Production and Livestock Farming Systems.