1. Institute of Bioscience and Department of Animal Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia, Guangdong Institute of Eco-Environmental and Soil Sciences, Guangzhou 510650, P.R. China, Key Laboratory of Ecological Agriculture of Ministry of Agriculture of the People’s Republic of China, and College of Nature Resources and Environment, South China Agriculture University, Guangzhou 510640, P.R. China