Crossbreeding effects on growth and efficiency in beef cow-calf systems: evaluation of Angus, Caracu, Hereford and Nelore breed direct, maternal and heterosis effects

杂交育种对肉牛母牛-犊牛系统生长和效率的影响：安格斯、卡拉库、赫里福德和内洛尔品种的直接效应、母系效应和杂交优势的评估