Lactating cows naturally have limitations with feed intake, particularly with dry matter feed. As a result, a dairy cow’s digestibility is reduced with increased feed intake (Tyrell and Moe, 1975).
This reduces the energy value of any given diet as the feed intake increases. This is particularly important in milk producing cows, where it is uncommon for feed intake to exceed 4 times the maintenance level. The decline rate in digestibility with level of feeding has been proven to be related to the digestibility of the diet at the maintenance level (Wagner& Loosli, 1967).
To be profitable from dairy farm operations, maximising the energy intake of dairy cows while minimising the negative energy balance is imperative.