Milk replacer costs have risen slightly on 2024 prices. The average price of milk replacer in 2025 comes in at €2,625/tonne or 33 cent/litre compared with a cost of €2,535/tonne in 2024 or 32 cent/litre.

Table 1 outlines the costs and details of milk replacers available on the Irish market.

Costs

To work out how much it costs to feed a calf on milk replacer, you multiply the cost per litre of mixed milk replacer by the amount of litres that you are feeding.

In general, calves fed on milk replacer get 4l to 6l a day. You could also compare the price by the amount of grams of milk powder that they are fed daily, as the powder is the important part when it comes to nutrition.

Teagasc guidelines recommend that a calf should receive at least 13-15% of its birth weight in good-quality milk replacer.

Milk replacer is generally mixed at the rate of 125g per litre of water. The mixing rate sometimes varies between milk replacer manufacturers.

The amount of milk fed and concentrate intake determines calf growth rate in the period up to 12 weeks, with a target of getting a calf to grow from 45kg to 100kg during that time.

Teagasc also says that once calves have received 8.5% of their birth bodyweight in colostrum within two hours of birth, there is no difference in their weight gain pre- or post-weaning, compared to calves fed colostrum and four feeds of transition milk before moving on to milk replacer.

Skim vs whey

The term skim refers to a dairy protein which contains approximately 80% casein and 20% whey proteins. Skim powder is derived from butter-making. When the powder is reconstituted in the manufacture of milk replacers, vegetable oils replace the butter fat.

Traditionally, skim-based milk replacers contain a defined skim content, but today the levels can vary from 20% to 60%. Skim-based powders tend to be more expensive. Whey-based powders are derived from cheese-making.

When made into a milk replacer, vegetable proteins are used to replace the milk proteins extracted to make the cheese. Whey proteins contain a higher level of essential amino acids than skim proteins.

In addition, at low processing temperatures whey proteins can also contain high levels of the immunoglobulins found naturally in milk and colostrum.

Although some farmers believe that artificially-reared calves should be fed skim-based replacers, studies have shown that calves fed whey-based milk replacer perform at least as well as those on skim milk-based replacer in terms of daily liveweight gain.

Mixing milk replacer

When mixing milk replacer, calculate the total amount of feed you need. For example, if you are feeding 10 calves 2l of milk, you need 20l of mixed milk in total. If the feeding rate is 15%, the calves need to get 300g of powder each at each feed, or 3kg of powder for the bunch.

Because milk powder will displace water, you should reduce the amount of water used by the quantity of powder.

So instead of mixing 3kg of powder into 20l of water, you should mix 3kg of powder into 17l of water, to make 20l of mixed milk.

When mixing, pour the correct amount of milk powder into half the desired amount of water and mix with a whisk or other mixing device. Then add the rest of the water.

Never mix with boiling water, as this could corrupt the proteins. Only ever mix and feed with water at or below body temperature. Most milk replacer can be successfully fed cold.