5Pesti.G.M.et al., Study on the Effect of Feeding Cupric sulfate pentahydrate to laying hens on Cholesterol content[J]. Poultry Sci., 1998,(77): 1540~1545.
6NRC[S]. Nutrient requirments of poultry, 1983,8thed.
7David Farrell.The problems and practicalities of producing an omeqe(n)-3 enriched egg World Poultry,1996,12:39~43.
8Mannion, P.F.,Weight responses of laying hens fed different concentration of vegetable oil and linoeic acid[J].Agric,1992,(43):389~397.