NativeCalfConcept

Many farms therefore successfully use whole milk as the basis for high milk intake, excellent daily weight gain and a healthy start to life. At the same time, whole milk is an economically attractive feedstuff, as it is available on the farm and does not need to be purchased – particularly when using milk that is not suitable for the market. Milk from cows treated with antibiotics is, of course, not included in this and should always be discarded.

However, feeding whole milk also presents certain challenges.
Quality can vary, hygiene and storage are crucial, and untreated raw milk can transmit pathogens. Furthermore, field studies show that whole milk is often unintentionally diluted on its way from the udder to the feeding trough, which can significantly reduce its energy and nutrient content.

Milk replacers offer clear benefits in calf rearing when used correctly.

Consistent quality: Each feed contains the same amount of energy, protein, fat and vitamins. This provides a sense of security for the calf, as calves prefer a consistent feed with the same composition every time.

High hygiene levels: CMR is microbiologically stable when mixed properly and handled correctly, reducing bacterial load and lowers the risk of digestive problems.

Predictability and efficiency: Milk replacer is available at any time, regardless of milking times; it is easy to measure out and simple to use. This makes calf rearing easy to plan and efficient.

Providing at least 10 to 12 litres of milk per day – ideally ad libitum – promotes growth and supports the development of the udder. In practice, calves drink around 8 to 10 litres in their first week of life when given free access to feed, and often considerably more thereafter.

From a biological perspective, an unlimited supply of milk is not an exception, but the natural state for young mammals. Restrictive feeding is more the exception than the rule.

Of course, this is conditional on the quality of the milk, hygiene and feeding techniques being up to standard – as described in the previous chapters.

A common argument is that calves that consume a high volume of milk tend to start consuming concentrate later. This is correct – but not necessarily a bad thing.

Studies show that calves that are fed intensively go on to develop a capacity to consume large amounts of feed. Their metabolism has become accustomed to processing larger amounts of nutrients. This could be one reason why these animals produce more milk later on, as they make more efficient use of the nutrients available to them.

What matters, therefore, is not how early a calf starts eating concentrate, but how consistently and effectively it develops overall.

While calves do begin to produce enzymes for digesting plant proteins and carbohydrates from the fourth to fifth week of life, it takes several more weeks, however, for the digestive system to become fully functional.

Withholding milk too early often leads to a typical scenario on many farms: the so-called weaning dip. Growth stagnates for 1 to 2 weeks – or the calf may even lose weight. This is a clear indication that the energy loss from milk cannot yet be fully offset by plant-based feed.

The situation becomes even more critical if feeding is discontinued abruptly, for example when a complete feed is suddenly omitted. The calf’s metabolism is overburdened, leading to stress – the calf becomes unbalanced.

Concentrate plays a central role in the development of ruminants. It provides fermentable nutrients that are broken down by microorganisms in the rumen. This produces volatile fatty acids, which stimulate the growth of the rumen villi, thereby increasing their surface area for nutrient absorption.

Concentrate is therefore not just a source of energy – it also stimulates rumen development.

At the same time, the ingredients must be selected with care. The aim is to provide easily digestible feed that promotes rumen development without causing over-acidification.

Energy sources such as maize and oats are often more suitable for feeding calves than sources of starch that are readily available, such as wheat. The key is to strike a balance between energy, composition and digestibility.

Concentrate intake is often used as the sole indicator to determine when to wean. A daily intake of around 1 kg of concentrate is often taken as a sign that a calf is ‘ready’. However, we know that a longer weaning period of up to around 12 weeks can be beneficial – even if the intake of concentrate increases at an early stage.

It is not just the amount of feed that matters, but the calf’s overall development. It is difficult to accurately measure individual concentrate intake when calves are kept in groups. Weight gain is therefore a more meaningful indicator. Steady, consistent weight gain indicates that digestion, metabolism and energy supply are in balance.

You can find further information on feeding concentrate in the 3-part series of articles on our blog.

On many farms, calves are only introduced to calf feeders after a period of 2 to 3 weeks. Until then, they drink from the feeding bucket in single or twin hutches and are later transferred to larger groups.

This results in additional costs, the need to repeatedly train calves to use different feeding systems, extra work and unnecessary stress for the calf.

Modern approaches therefore go one step further.

The system requires well-thought-out group sizes and clear procedures in order to function properly. We recommend:

• A maximum group size of 15 calves,
• An age difference of preferably less than 3 weeks and
• No merging of existing groups.

With a feeding period of around 10 to 11 weeks, this means several established groups with a clear structure. Although this may initially appear to require a higher investment, practical experience often reveals the benefits:

• The workload is reduced thanks to the one-time training session.
• There are fewer cases of illness because nutrition provision is better.
• Weight gain is improved by more intensive feeding.
• Data transparency is improved thanks to CalfExpert's detailed analyses in CalfGuide.