breeding herd
1.48 Durocs were randomly selected at 28 days of age from the second generation of American Duroc Breeding herd which was imported in 2001 from U.S. The 48 gilts werefed in nursery house till they were 70 days of age at about 33 kg body weight. For the growing-finishing phases the pigs were fed with diets at DE l3.3~13.1MJ/Kg and CP 18.01％~16.03％.
2.female Duroc were randomly selected at 28 days of age from the second generation of American Duroc Breeding herd which was imported in 2001 from U.S. The 48 females were fed in nursery house till they were 70 days of age at about 33 kg body weight. For the growing-finishing phases the pigs were fed ad libitum with diets at DE 13.39 MJ/kg and CP 18%～16%.
