Effect of Adding Cod Liver Oil to the Rations of Dairy Calves

Abstract

Some calves dropped in the dairy herd at University Farm are weak at birth, and develop ini~gestion or other aihnents and a few die before they are a month old. The cows in the herd are fed largely oll a barn-feeding basis throughout the entire year because little or no pasture is available. Fair to good quality roughage is fed. Meigs and Converse (6) have shown that the quality of roughage fed to cows has a marked effect on the health and vigor of their calves at birth. Similarly the beneficial effect of feeding a vitamin A supplement to calves for several weeks after birth or until they are consuming considerable quantities of hay has been demonstrated by Phillips (7). If carotene-poor roughage is fed, or if young calves, for any reason, fail to utilize the carotene supplied then the feeding of a vitamin A-rich product beyond the first few weeks should prove beneficial. Ellen- berger (4) reported that neither calves raised to 240 days of age on poor quality roughage nor those fed good hay for the same period evidenced any lack of vitamin A. Calves fed the poor hay, however, made "slower, lesser, and more costly growth" as caused by their lower consumption of nutrients in the less palatable ration. When good quality hay was fed, no benefits ap- peared from feeding cod liver oil, instead growth in some eases seemed to be retarded. Cary (2) states that calves fed skim milk, grain and hay after 30 to 60 days of age must, in order to survive, receive a vitamin A supple- ment if fed hay as poor in carotene as U. S. No. 3 alfalfa or timothy. Feed- ing at the rate of 20 milliliters of cod liver oil per calf daily to six months of age, however, had no demonstrable effect on their general appearance and rate of growth when U. S. No. 2 alfalfa hay or better was fed. Similarly, Insko and Rupel (5) observed no marked difference in the rate of growth and composition of bones between calves fed a standard ration, including' good quality legume hay, and others reared on a similar ration supplemented with cod liver oil. Similar results have more recently been reported by Reaves and Cannon (8). In a eamparison involving four pairs of calves from dams that presumably obtained a normal allowance of pasture, Dahl- berg and Maynard (3) fed varying amounts of Nopco XX, a vitamin A and D rich concentrate of cod liver oil. Both lots weighed exactly the same at the start, but the supplemented group soon forged ahead and at 26 weeks of age each averaged 18.7 pounds more than those in the check group. The