Hitting heifer liveweight targets
Early December marks a key transition for many dairy farmers, as weaned replacement heifers head off-farm to grazing.
Feeding the right supplement through your in-shed feeding system will ensure that you maximise milk returns and supplementary feeding profitability.
Processed maize grain is an excellent choice. Maize has a higher energy content than other grains and many other commonly available concentrates.
It can be used to increase cow energy intakes, delivering more milk or faster condition score gains.
Information published by DairyNZ shows that milk production is determined by the amount of energy a cow eats but the composition of the milksolids she produces is affected by the type of supplement fed.3
When cows are fed a starch or sugar-based supplement, they produce more milk protein.
When cows are fed a fibre based supplement, they produce more milk fat.
Since milk protein is worth two to three times more than milk fat, starch and sugar based supplements will deliver more milk revenue than fibre-based supplements.
As well as containing more energy than other concentrates (e.g. dairy meal, other grains), maize grain has advantages for rumen health.
It has a high starch content but virtually no soluble sugar.
Maize starch is less rapidly broken down in the rumen than other starch types.
This means there is a lower risk of acidosis (grain overload) when feeding maize grain compared to other grains (e.g. wheat) or high sugar feeds (e.g. molasses).
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 for cows are:
Feed a maximum of 30% of the total drymatter intake as maize grain.
Start at lower rates (e.g. 1kg maize grain per cow per day and increase feeding rates gradually over 7-10 days).
Feed a maximum of 2.5kgDM maize grain in a single feed.
Feeding rates will be lower in diets that contain other sources of carbohydrate (e.g. other grains or meals, molasses or high sugar or starch byproducts).
Maize grain is an ideal supplement for pasture-fed calves and young stock promoting rapid rumen development and excellent liveweight gains.
Processed maize grain can be purchased as required from most local grain companies.
For more information:
Tel. 0800 746 633
• Ian Williams is a Pioneer forage specialist. Contact him at This email address is being protected from spambots. You need JavaScript enabled to view it.
1 Feed values taken from Holmes et al. 2003. Milk Production from Pasture, Massey University, NZ.
2 Palm kernel extract feed value taken from Kolver E. 2006. PKE – Economically priced supplement. Dexcelink Autumn 2006. Dairy Meal energy content is an estimate only.
3 Adapted from Roche and Hedley, 2011. Supplements – the facts to help improve your bottom line. DairyNZ Technical Series July, 2011 p 6-10. Assumes grazing residuals of 1,500-1,600 kgDM (7-8 clicks on RPM). Responses decline when residuals are higher than 1,600 kgDM (i.e. cows are better fed). For a full list of assumptions see http://www.dairynz.co.nz/file/fileid/37671.
