1. Beijing Key Laboratory of Optimization Design for Modern Agricultural Equipment, College of Engineering, China Agricultural University, Beijing 100083, China
2. Quality & Safety Assessment Research Unit, U. S. National Poultry Research Center, USDA-ARS, 950 College Station Rd., Athens, GA 30605, USA
3. Crop Genetics and Breeding Research Unit, United States Department of Agriculture Agricultural Research Service, 2747 Davis Road, Tifton, GA 31793, USA