Step 3:

Vitamin boost for
better resistance

Calf immunity develops more quickly with extra vitamins and minerals

Antibodies in the colostrum can only protect the newborn calf against pathogens for the first few days of its life. The young animal must therefore develop strong immunity to disease as soon as possible after birth. The best possible resistance is built up through intensive milk feeding following the colostrum, with extra iron, vitamins and minerals. 

The antibodies in the colostrum give the calf so-called passive immunity, which it needs in order to get through its first days.  In step 2, we describe the protocol for effective colostrum management and thereby optimum development of the passive immunity, which otherwise starts to decline within a few days of the colostrum. In order to stay healthy therefore, the calf must quickly build up its own active immunity, within 14 to 21 days. From then on, calves will be less susceptible to disease.

Resistance under the critical level for as short as possible

The rule of thumb is:  the better the first (colostrum) feed and the better the milk fed from day 2, the smaller the risk of the calf having less immunity and therefore being more susceptible to disease at any point in the first 21 days. The challenge is therefore to apply optimum colostrum management to extend the passive immunity as long as possible while developing the active immunity as quickly and strongly as possible. However:  there will always be a (slight) risk of the immunity being under the critical level at some point.


Extra vitamins and minerals for the calf

This risk can be limited or even precluded by adding extra vitamins, minerals and trace elements to the milk feed for five consecutive days as from day two, including extra iron to combat anaemia.

These extra additives are useful and possibly even essential, because a calf's vitamin and mineral requirements in the first days cannot be met by what it receives via calf replacement milk.  Good calf's milk contains a balanced menu of vitamins and minerals, and the calf's requirements can be largely met by means of intensive feeding (see step 5). In the early days of feed intake however, the supply very rarely meets what the calf needs for optimum immunity development.

By enriching the milk (colostrum and calf milk) with essential nutrients, you give the calf the best possible start in life. The calf will quickly grow stronger and develop active immunity more quickly.

Note: this is only effective if the initial colostrum feed (step 2) and the start-up with calf milk (step 5) are implemented and planned well. The combination is what counts: addition of vitamins and minerals can never compensate poor colostrum management or a poor start-up with calf milk.


Good immunity development due to optimum colostrum management, intensive calf milk feeding following the colostrum and extra vitamins and minerals as from day 1.


There are various products which make it simple to mix extra vitamins, minerals and trace elements through the colostrum and the calf milk.  An example is Farm-O-San StartFit. StartFit includes substances which trigger the calf's appetite and therefore stimulate it to take in milk. An important component is easily absorbed iron. Young calves soon suffer from anaemia, so that extra iron is very welcome.  StartFit is also a suitable solution for older calves who need a nutrition boost for various reasons.

5-day course

StartFit is very simple to use.  Per meal, dissolve 5 grams of StartFit in the milk. We advise starting this straight away in the colostrum. The calf then receives a 5-day 'course of vitamins'.

Older calves which need an extra boost, following illness or transport stress for example, can also be fed 5 grams per milk feed for 5 consecutive days. Always pay attention to the temperature of the milk, which needs to be approximately 40 degrees. Overly cold milk will give problems.

Questions about the immunity of your calves?

 Could you do anything extra to bring the resistance of your newborn calves up to standard more quickly? Ask the Sprayfo rearing specialist in your region!

Direct advice


Questions about the immunity of your calves?

Could you do anything extra to bring the resistance of your newborn calves up to standard more quickly? Ask the Sprayfo rearing specialist in your region! 

Direct advice