Genetic Technologies Limited


Maize silage for heifers

Maize silage for heifers

Well grown heifers lead to high producing cows, and the right feed will help ensure heifers meet target weights at calving which ensures high long-term milk production. Feeding maize silage will give your heifers a healthy start and guarantee you have enough feed to ensure they bring you maximum long-term profit. 

How heavy should young stock be?

New Zealand research has shown that heifer weight gain after puberty (around 11 to 12 months of age) has a direct impact on milk production.

So, just how heavy should your heifers be?

According to DairyNZ targets, young stock should be:

  • 30 percent of their mature weight by six months
  • 40 percent of their mature weight by nine months
  • 60 percent of their mature weight by 15 months (mating age)
  • 90 percent of their mature weight at 22 months.

Maize silage it is a great feed for young stock for a number of reasons:

The mix of highly digestible grain as well as fibre (from the plant) makes maize silage highly palatable and safe to feed.

Being a safe, clean feed, feeding maize silage reduces worm loadings and the risk of facial eczema, common problems for young stock grazing to low pasture residuals.

Maize silage can be stored and fed when required, protecting young stock against fluctuating pasture levels.

Maize can be grown in high fertility dairy paddocks, without the need for additional fertiliser, for 16 c to 20 c kg/DM. This makes it a cost-effective way of delivering extra energy to your heifers.

Introducing maize to replacement stock means that there is a seamless entry into herd’s feeding regime when the new heifers enter the herd of the first time.  This removes the risk of “shy or reluctant feeders”.

Maize silage feeding rates

Typical protein requirements for heifers are shown in Table 1. Recommended maize silage feeding rates will vary depending on the age and weight of your heifers and the protein content of the pasture they are being fed. Maize silage is typically introduced post-weaning at up to 25% of the diet with feeding rates rising to 40% of the diet for rising 2 year olds on high protein pasture.

Table 1: Typical protein requirements of heifers

Heifer weight

Typical protein requirements

25 – 225 kg


250 - 325 kg


350+ kg


For more on the benefits of maize silage for your farm contact your local Pioneer representative.