As ruminants, cattle can ideally use forage as a source of energy and protein. However, this requires a fully formed forestomach system with a well-developed rumen. After birth, it takes up to half a year until a forestomach is completely mature and ready to perform to its full potential.

Since young animals are not able to digest much of the basic feed at this stage, it is important to provide them with a good supply of concentrate. For this reason, there is a widespread belief that only easily digestible concentrate should be used for calves. In fact, butyric and propionic acid, as degradation products of easily digestible carbohydrates, ensure good development of the rumen villi in the rumen. This results in an enormous increase in surface area in the rumen and the volatile fatty acids that are produced during digestion in the rumen can be absorbed perfectly.

A newborn calf can only digest milk components. The enzymes in the abomasum are adapted to digest milk protein and lactose (lactase or chymosin and cathepsin). It is only after 3-5 weeks that this changes and the digestive enzymes amylase for digesting starch and pepsin and trypsin for breaking down plant protein begin to dominate.

In fact, it is only after an age of 4 weeks that you notice that the concentrate intake of the calves slowly increases. This could be even later when feeding is intensive (e.g. ad libitum).

Nevertheless, it makes sense to provide calves with roughage during the first two weeks of life. They play with it and start to get used to its smell, taste and texture. Offering concentrated feed at an early stage also has a positive effect on the way the enzyme system develops and promotes the development of the rumen from an early stage (see above). Offering hay in pens, nets or toy balls also encourages the calves to be active.

It shouldn't really be necessary to point out the importance of the cheapest feed available, but we still see major deficiencies in the supply of water to calves. Whether for reasons of hygiene or simply the fact that there is no water trough in front of many individual huts, one thing is certain –

we are not only legally but also ethically obliged to provide all animals with fresh water and that includes young calves.

Calf feed or cereals are relatively expensive. The question therefore arises as to when to switch to silage (preferably the high-performance ration of dairy cows). The answer can be found at the beginning of this blog – a heifer's forestomach system is not fully developed until she is about 6 months old. This is why at least high-quality concentrate should be fed until this time. However, you must always keep an eye on animal conditioning. Nevertheless, it is generally true that heifers can and should be fed intensively up to 6 months of age in order to achieve high weight gains during this important phase of their development.

The transitions are important. Feeding silage is difficult in many calf barns due to their design (no space, no access for the feed mixer cart etc.). It is also unclear how to deal with leftover feed, of which there is a lot at the beginning of the transition. What was previously introduced with great effort has to be removed again the next day.