Evaluation of High Starch and High Fat Rations for Dairy Calves

Abstract

Sixty-four Holstein calves were in a 3×2 factorial experiment of 12 wk starting at 3 days of age to evaluate growth performance when calves were fed control, high starch, and high fat pelleted diets separately or with a supplemental concentrate mix offered the first 6 wk. High starch and high fat diets were formulated to contain more digestible energy (3.48 Mcal/kg dry matter) than the control diet (3.31 Mcal/kg dry matter). Calves received whole milk the first 5 wk plus one of these rations ad libitum wk 1 thru 12. The control diet contained corn, oats, and soybean meal; the high starch diet contained corn and soybean meal; and the high fat diet contained corn and an extruded whole soybean product. All pelleted diets contained 20% ground alfalfa-bromegrass hay, 5% dry molasses, and 1% each of dicalcium phosphate, trace mineral salt, and antibiotic premix. The supplemental concentrate mix contained corn, oats, and soybean meal, 9% liquid molasses, minerals, and vitamins. Weight gains, feed intakes, and ratios of feed to gain were similar for all three pelleted diets with or without the supplemental concentrate mix during wk 1 thru 5, 6 thru 12, and 1 thru 12. Calves offered the supplemental concentrate mix during wk 1 thru 6 tended to consume more total feed than calves offered only pellets. Apparent digestibilities of control, high starch, or high fat diets measured for twenty 13-wk old male calves were generally highest for the control diet. Apparent digestibilities of the respective diets were: dry matter, 81.3, 77.7, and 76.1%; energy, 80.1, 76.5, and 75.9%; nitrogen, 83.4, 77.8, and 76.1%; and ether extract, 89.0, 80.0, and 90.0%.