Effects of Earthworms Cultivated in Munieipal Sewage Sludge on Feeding Laying Hens
城市下水污泥养殖的蚯蚓对产蛋鸡的影响

The earthworms cultivated in municipal sewage sludge was treated with boiling water and then added to the diets of laying white Leghorn hens at rates of 10% (fresh weight), The diets containing earthworms were fed to hens for 60 days. Feed intake, egg production, egg weight and the rate of egg lay were determined daily throughout the experiment. Relative liver weight was measured and tissues were collected for chemical analyses and pathological examination at the end of experiment. The results showed that the consumption of feed increa-led significantly (P<0.05) during the experifeht, egg production reduced significantly (P<0.05) after 30 days and hen livers were injured. Health and performance were affected adversely. However, the elemental concentrations of six metals (Cd, Pb, Hg, Ni, Cu and Zn) in eggs and breast muscle did not increase significantly.