Abstract: Ninety crossbred weaning piglets were randomly divided into 3 groups with 30 piglets each. In the weaned pig period, growing pig period and finishing pig period, the pigs in control group were fed with weaned pig diet, growing pig diet and finishing pig diet, respectively. The pigs in trial group 1(Chinese herbal medicine group) were fed with diets added with 3 500, 3 000 and 2 500 mg·kg-1 Chinese herbal medicine additives into relevant control diets. The pigs in trial group 2 (plant extract group) were fed with diets added with 800, 600 and 500 mg·kg-1 plant extract, a foreign patent plant extract additive. It was found that the average daily gains of control group, trial group 1 and trial group 2 were (587.47±91.93), (604.78±91.06) and(601.44±72.26) g in total trial period,respectively. The feed conversion ratios of above groups were 3.42±0.11, 3.23±0.26 and 3.41±0.22,respectively. Antibody positive rates of classical swine fever (CSF) in trial group 1, trial group 2 and control group were 83.3%, 41.7% and 41.7%, respectively. Antibody positive rate of CSF in trial group 1 was significantly higher than those in trial group 2 and control group (P<0.005), in addition, the elimination rate decreased by 33.3% and 33.3%, in comparison to those of control group and trial group 2, respectively. The economic benefit of trial group 1 increased by 40.96% and 95.89% more than those of control group and trial group 2. The results suggested that the Chinese herbal medicine additives show improving effects on pig's productive performances, disease resistance and economic benefits．

Key words: Chinese herbal medicine additives, swine, productive performances, antibody against CSF