Choosing the right milk replacer for young calves

The selection of milk replacers for calves is extensive – making it all the more important to know the right criteria before making a purchase decision. The requirements for the milk feed change depending on the rearing phase and age of the calf. This is because both age and previous feeding influence the production of digestive enzymes – and thus the digestibility and effectiveness of the milk replacer.

What is important for milk replacers in the first weeks of life?

Immediately after colostrum feeding, calves require a high-quality milk replacer.

Important criteria:

• Nutrient density: min. 19% crude fat & 22% crude protein
• Protein source: high milk protein content (skimmed milk powder > 50%)
• Digestibility: casein content supports protein coagulation in the abomasum
• Crude ash content: < 8% (too much reduces digestibility)
• Health additives: pro- & prebiotics, organic acids → promote gut health, especially in the first weeks of life

Conclusion for the early phase

In the first weeks of life, calves benefit from a skimmed milk-rich milk replacer with a balanced nutrient content – it is easily digestible and well-tolerated. Pro- and prebiotics as well as organic acids also strengthen the intestinal flora and contribute to healthy development.

Milk replacer for later weeks of life in calf rearing 

With increasing age, nutritional physiological requirements change. 
Calves initially reared on skimmed milk-rich products or whole milk can later be switched to more cost-effective options.

• Products with lower skimmed milk content or whey-based products are common.
• Quality and composition are crucial – not just the price.
• Crude fiber content indicates the proportion of plant components.
• A higher plant content often lowers the price but can impair the solubility and settling behavior of the product – especially if the feed is not given immediately after mixing.

Conclusion for the transition phase

When switching to follow-on milk replacers, price alone should not be the deciding factor. The right balance of nutrient content, solubility, and digestibility is essential to ensure consistently high rearing performance.

Protein sources in milk replacers 

In addition to skimmed milk powder and whey protein, plant-based protein sources such as wheat protein or soy protein concentrate are also used.

• These promote enzyme formation in the digestive system.
• They prepare the calves for the utilization of plant-based food during the weaning phase.
• Therefore, it makes sense to switch to products with plant-based protein sources from the second feeding phase.

From left to right: Soy protein - Wheat protein - Whey protein - Skimmed milk (Casein)

Fats in milk replacers – quality counts!

Fats provide energy and influence the digestibility of the feed. Palm and coconut fat are common, but rapeseed or sunflower oil are increasingly being used.

• JOSERA milk replacer Extramil 50 exclusively contains rapeseed fat as a fat source, as well as a native fat content from buttermilk powder.
• This ensures high energy density and particularly good digestibility.
• The fat droplet size is crucial for fat utilization.
• JOSERA uses spray-dried fats (< 2 μm) – they distribute evenly in the feed and are optimally digestible.

Practical tip: 

When mixing, ensure a temperature of 40–45 °C to secure emulsification.

Green = well-emulsified fat 
Red = poorly emulsified fat

Price & availability – what to look for?

Milk replacers are among the most expensive feedstuffs in rearing. Of course, price plays a role in the decision – but caution: 

• A cheap product can become expensive if the composition is not right. 
• Inferior quality leads to poorer nutrient supply → more disease risks and longer rearing time.

Read our guide on ad libitum feeding in calves here.

Conclusion: The right choice is crucial

When selecting a milk replacer, not only price and skimmed milk content matter. 
Important criteria are:

• Nutrient content (protein, fat, crude ash)
• Protein sources (milk or plant protein)
• Fat quality (source, emulsification)
• Health additives (probiotics, acids)

Only with these factors can it be determined for which rearing phase a milk replacer is suitable. 
Professional use pays off – in healthy, high-performing calves and economically successful rearing.