Energy metabolism in high yielding cows

Abstract

Whilst current rationing systems are used to calculate the metabolisable energy (ME) requirements of dairy cows producing more than 50kg milk/day, the extent to which the digestive efficiency of the cow may be compromised at high intake levels has not been established. Equally the effect of a sustained energy deficit on milk composition is not known whilst the extent of energy contribution from mobilised tissue has not been quantified. This study was designed to examine energy metabolism in high yielding cows offered ad libitum total mixed ration during early/mid lactation.