1. Department of Engineering, Group of Animal Production and Rural Development, Production and Agricultural Economy, La Laguna University, La Laguna, Spain
2. ICIA, La Laguna, Spain
3. Department of Engineering, Agricultural Economy, Sociology and Policy Unit, Production and Agricultural Economy, La Laguna University, La Laguna, Spain
4. Animal Production Unit, Las Palmas de Gran Canaria University, Arucas, Spain