Maize grain feeding guidelines

Above: Cows eating a mix of feeds including maize grain and maize silage.

Feeding Rates

Maize grain feeding rates will vary depending on the age and production level of livestock and the amount and
type of other feeds in the diet. General recommendations are as follows:

  • Feed a maximum of 30% of the total drymatter intake as maize grain*.
  • Start at lower rates (e.g. 1 kg maize grain per cow per day) and increase the feeding rates gradually over 7-10 days.
  • Feed a maximum of 2.5 kgDM maize grain in a single feed.

* Feeding rates will be lower in diets that contain other sources of carbohydrates (e.g. other grains, dairy meal, molasses or high sugar or starch byproducts). Talk to your local veterinarian or nutritionist for farm specific advice.



Acidosis can occur when cows are fed either too much starch or sugar, or where the starchy/ sugary feed has been introduced too rapidly into the cow’s diet. Starch and sugars are digested quickly by microorganisms in the rumen of the cow. The end products of this digestion are acids, which the cow then uses for energy. However, when a cow eats a lot of starchy or sugary feeds and/or she is not accustomed to these feeds, she produces dangerous levels of lactic acid, becomes ill, and in severe cases can die.

To reduce the risk of rumen acidosis always:

  • Introduce high starch or sugar feeds into the diet slowly.
  • Watch total dietary levels of starchy or sugar feeds.
  • Ensure that the diet contains adequate levels of long (functional) fibre.
  • Ensure that individual animals cannot gorge high risk feeds.