1. a IRTA, Monogastric Nutrition , Centre Mas de Bover , Carr. Reus-Morell, km 3.8, 43120 Constantí (Tarragona), Spain
2. b Lesaffre Feed Additives , Rue du Haut Touquet, 1, 59520 Marquette-Lez-Lille, France
3. c Department of Pathology, Bacteriology and Avian Diseases, Research Group of Veterinary Public Health and Zoonoses, Faculty of Veterinary Medicine , Ghent University , Salisburylaan 133, B-9820 Merelbeke, Belgium
4. d Saf-Agri , Mexico, Km. 57.5 Carretera Mexico-Toluca, C. P. 50200 Toluca, Estate of Mexico, Mexico