Balancing the Nutritional Deficiencies of Roughages for Beef Steers

Abstract

Five experiments are reported in which ground corn cobs, oat straw, soybean straw, corn silage or grass silage were fed as the sole source of roughage to calves or yearling steers. Each steer received, in addition to the roughage being tested, a daily feed of 2.25 pound soybean meal, 1 pound molasses feed, minerals and a vitamin A and D concentrate (Purdue Cattle Supplement A). When the individual roughages were fed with Purdue Cattle Supplement A, the following average daily gains were recorded: ground corn cobs, 1.28 to 1.56 pound; oat straw, 0.78 pound; soybean straw, 0.78 pound; corn silage, 2.06 to 2.21 pound; grass silage, 2.01 pound. Some modifications of the original Purdue Cattle Supplement A were made for steers being fed corn cobs. When urea was used to replace from one-third to two-thirds of the protein equivalent supplied by soybean oil meal and this supplement was fed with ground corn cobs, no significant difference in growth rate was obtained when the gains of such fed animals were compared with those of steers receiving all their protein from soybean oil meal. The addition of vitamin B₁₂ or fish meal gave some apparent growth stimulation, although the difference was not significant. Although the addition of live cell yeast gave an apparent growth stimulation, the addition of neither live cell yeast nor brewer's yeast resulted in a significantly increased growth rate. The addition of two pounds of alfalfa meal—replacing two pounds of corn cobs—resulted in significantly increased growth. Steers received no growth stimulation from the addition of distiller's dried solubles. Copyright © . .