1. Centre for Nuclear Energy in Agriculture; N.A.P.T.I.S.A.; University of São Paulo; Piracicaba São Paulo Brazil
2. Faculty of Agriculture and Veterinary Medicine; University of Brasília; Brasília Distrito Federal Brazil
3. Centre for Research and Development of Animal Nutrition and Pastures; Institute of Animal Science; APTA; SAA-SP; Nova Odessa São Paulo Brazil
4. Institute of Biological Sciences; University of Brasília; Brasília Distrito Federal Brazil