Abstract: 36 healthy dairy cows whose milking days are 90-150,hypo-padding are 25，LW are similar were selected，and divided into four groups （P>0.05）according to Complete Random Design. Each group received one treatment,group4 was control group, group1,2 and 3 supplemented rapeseed, rape oil and fatty acid calcium respectively。After 30days experimentation, the results shown the daily milk yield of group 1,group2 and group3 enhanced 0.88 (P<0.05), 0.31(P>0.05), 0.31(P>0.05),0.70(P<0.05) kg/h/d . No significant difference fund Between all groups' DMI and FCR; Even SNF shown an increased tendency, supplementation of rapeseed (350g/h/d), rape oil (150g g/h/d) and fatty acid (200g g/h/d) did not affect the composition of milk SNF（P>0.05）. Supplementation of fatty acid (200g g/h/d) increased milk fat significantly, but .that of rapeseed (350g/h/d), rape oil (150g g/h/d) had no any positive effect on the composition of milk SNF (P>0.05). group1 profited extract 1.08 Yuan kg/h/d, group2 lost 0.06 Yuan, group3 lost 0.14 Yuan kg/h/d;Above results shown supplemented rapeseed (350g/h/d) to the dairy cow whose milking day are 90-150, increase economical efficiency, supplementation of fatty acid enhanced the milk quality.

Key words: dairy cow; rapeseed; rape oil; fatty acid calcium; performance; milk yield