broilers(5 groups)were fed from dqy one to day forty.The feeding periodwere divided into two parts,0～23 day period and 24～40 day peried.Different ion-type rare-earth and rich-Cerium rare-earth were added to the diets. The Concentration of the rare-earthwas 45 mg/kg. It was indicted that the growth of the broiler among the different groups werenot signifieantly different in the 0～23 day period. At 40 days,No. 1 non-yttium ion-typerare-earth had significant effect to the growth of the broiler. Compare with the CK.No. 2 yt-tium rare-earth and r...
