Title: Effects of Silage pH on Voluntary Intake of Corn Silage
Abstract: We evaluated effects of silage pH on corn silage intake.Sixteen Holstein heifers (292 kg) were fed control corn silage during a 2-wk preliminary period.This was followed by an 8-wk experimental period in which animals were fed silage neutralized with 0, 2, 4, or 6% sodium bicarbonate (dry matter) added prior to feeding with corresponding pH's 3.72, 4.46, 5.62, and 8.05.Organic matter intake was increased 1.0 and 1.2 kg/day by addition of 2 and 4% sodium bicarbonate versus controls whereas 6% sodium bicarbonate reduced intake .7 kg/day.An equation developed to predict organic matter intake from silage pH was: Y = --3.20 + 3.92 (pH) --.35 (pH) 2 with coefficient of determination .66.This equation predicted maximum organic matter intake at pH 5.6.It appears that silage pH is a factor that affects voluntary consumption of corn silage and that pH 5 to 6 is optimum, whereas silage pH above and beIow may reduce intake.