4Havenstein G B, Ferket P R, Qureshi M A. Growth, livabil- ity, and feed conversion of 1957 versus 2001 broilers when fed representative 1957 and 2001 broiler diets [J]. Poult Sci, 2003, 82(10): 1500-1508.
5Lumpkins B S, Batal A B, Lee M D. Evaluation of the bacte- rial community and intestinal development of different genetic lines of chickens [J]. Poult Sci, 2010, 89(8) : 1614-1621.
6Torok V A, Hughes R J, Ophel-Keller K, et al. Influence of different litter materials on cecal microbiota colonization inbroiler chickens [J]. Poult Sci, 2009, 88(12): 2474- 2481.
7Torok V A, Kathy Ophel-Keller, Maylene Loo, et al. Appli- cation of methods for identifying broiler chicken gut bacterial species linked with increased energy metabolism [J]. Appl Environ Microbiol, 2008, 74(3):783-791.
8Wang Y, Cho J H, Chen Y J, et al. The effect of probiotie BioPlus 2B on growth performance, dry matter and nitrogen digestibility and slurry noxious gas emission in growing pigs [J]. LivestockSci, 2009, 120(1/2): 35-42.