Abstract
1. Groups of twenty-four heifers were used in three experiments lasting 51–98 days. The effect on rate of live-weight gain of the addition of 150 ml. cod-liver oil to the daily ration was studied.2. The same treatments were used in each experiment: a basal diet consisting of hay and concentrates and two experimental diets consisting of the basal diet plus (a) 3 lb. concentrates, (b) 150 ml. (0·30 lb.) cod-liver oil. In one experiment flaked maize was used in the concentrates in place of crushed barley.