1. Colegio de Postgraduados-Campus Montecillo, Carretera México-Texcoco Km. 36.5, Montecillo, Texcoco 56230, México
2. Extension Animal Sciences and Natural Resources, New Mexico State University, Las Cruces, New Mexico 88003, USA
3. Colegio de Postgraduados–Campus San Luis Potosí, Iturbide No. 73, Salinas, San Luis Potosí 78600, México