1. Department of Agriculture, West Texas A&M University, Canyon, TX
2. USDA-ARS Conservation and Production Research Laboratory, Livestock Nutrition Management Unit, Bushland, TX (Retired)
3. Escuela de Medician Veterinaria, Colegio de Ciencias de la Salud, Universidad San Fransisco de Quito USFQ, Quito, Ecuador
4. Texas A&M AgriLife Research, Amarillo, TX