Effect of type and site of acid neutralization on voluntary intake of corn silage by dairy heifers.

Abstract In Experiment 1, 16 Holstein heifers were used in a replicated 4 × 4 Latin square design that tested the effects of feeding 1) corn silage, 2) corn silage neutralized with 5.5% sodium bicarbonate (DM basis), 3) corn silage neutralized with 3.5% sodium carbonate, and 4) corn silage neutralized with 2.6% sodium hydroxide. Addition of neutralizing agents increased corn silage pH from 3.7 for the control to 5.1,4.9, and 5.0 for the sodium bicarbonate, sodium carbonate, and sodium hydroxide, respectively. Intake of silage DM as a percentage of BW was 2.29% for sodium bicarbonate treatment versus 2.05% for controls. Partial neutralization of silage using sodium bicarbonate resulted in higher intake of DM by heifers compared with neutralization with sodium carbonate and sodium hydroxide. Average daily gain was increased by .14 to .17 kg/d above controls regardless of neutralizing agent. In Experiment 2, four Holstein heifers were used to test the effects of partial neutralization of corn silage by sodium bicarbonate or ruminal infusion of an equivalent amount of sodium bicarbonate on corn silage intake and rumen fermentation. Intake was not affected by either feed or ruminal additions, suggesting that factors other than palatability and reducing ruminal acidity are involved in increasing the intake of corn silage treated with sodium bicarbonate.