Eighteen crossbred Holstein finishing steers of 200±25 kg weight were assigned randomly to one of the three groups of having 6 animals in each with different rations and different levels of calcium soap of long chain of fatly acids (Ca-LCFA) to study the effect on growth, feed conversion efficiency and dry matter intake in Mary Rose private dairy farm in Gorgan city, Golestan province of Iran. The experiment lasted for 120 days. Steers on the 1st group (control) received 0% of Ca-LCFA followed by 3% in 2nd group and in the 3rd group 6%. In this experiment average daily body weight (ADBWG), fed conversion efficiency (FCE) and dry matter intake (DMI) were measured. The average daily gains for the steers of 1, 2, and 3rd groups were 1.083, 1.0111 and 1.115 kg, respectively with fed conversion efficiency of 5.340, 5.688 and 5.898 with the differences among the treatment means been not significant. Average DMI for the entire period was 7.433, 7.467 and 7.565 kg, respectively which was not significant by different groups (P<0.05).
