Energy Balance Measurements with Corn Meal and Ground Oats for Lactating Cows

Abstract

Energy balance was measured with lactating cows consuming diets of 40% alfalfa hay, 5.5% soybean meal, and 54.5% of either corn meal or ground oats. The net energy value for lactation (Mcal/kg dry matter) of the oats diet (1.60) agreed with that predicted by −.12 + .0266 total digestible nutrients (% of dry matter) whereas the net energy value of the corn meal diet (1.67) was lower than predicted (1.72). The lower efficiency of the corn meal diet was associated with depression in milk fat content. Net energies of corn meal and ground oats determined by difference were 1.85 and 1.73 Mcal per kg of dry matter. Total digestible nutrient values of the total diets were considerably below comparable values listed in tables of feed composition published by the National Research Council. Actual total digestible nutrient values of the corn and oats dry matter by difference were 77 and 69%. Consecutive trials with animals consuming the same diets demonstrated that 1 wk was adequate for adaptation by cows previously unfamiliar with the respiration apparatus. © 1973, American Dairy Science Association. All rights reserved.