1. a LEPAE, Department of Chemical Engineering, Faculty of Engineering , University of Porto , Rua Dr Roberto Frias, s/n, 4200-465 Porto, Portugal
2. b CECAV-Veterinary and Animal Science Research Center, Veterinary Science Department , University of Trás-os-Montes e Alto Douro , Apartado 1013, 5001-801 Vila Real, Portugal