[1] Univ Sao Paulo, Fac Zootecnia & Engn Alimentos FZEA USP, Duque Caxias Norte 225, BR-13635900 Pirassununga, SP, Brazil
[2] Grasslands Res Ctr, AgRes, Tennent Dr,11 Dairy Farm Rd, Palmerston North 4442, New Zealand
[3] Univ Fed Minas Gerais UFMG, Inst Ciencias Exatas, Dept Quim, Av Antonio Carlos 6627, BR-31270901 Belo Horizonte, MG, Brazil
[4] EMBRAPA Instrumentacao, 15 Novembro 1452, BR-13560970 Sao Carlos, SP, Brazil
[5] Virginia Polytech Inst & State Univ, Dept Anim & Poultry Sci, 3480 Litton Reaves Hall, Blacksburg, VA 24061 USA