Institution: | a International Livestock Research Institute (ILRI), ILRI/ICRISAT, 12404, Niamey, Niger;b Animal Production Systems Group, Wageningen Agricultural University (WAU), 338, 6700 AH, Wageningen, The Netherlands;c Research Institute for Agrobiology and Soil Fertility (AB-DLO), 14, 6700 AA, Wageningen, The Netherlands |