Making the switch from bottle or bucket feeding to an autofeeder system is a big transition — for both calves and calf feeders. We’re used to calves bellowing for their morning bottle, hungry after 12 hours without milk. But that’s not normal for mammals.
What’s normal? Frequent, smaller meals — just like they’d get from their mothers.
That’s where the 40FIT ad libitum feeding plan comes in.
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on July 22, 2025 Do you have a good feeding plan?
Making the switch from feeding calves with bottles to the autofeeder is a big transition for calves and for the owner and calf feeder. We have been used to the following situations with bottle or bucket fed calves. On arrival in the morning as milk is being mixed and bottles filled the calves are bellowing loudly. These calves are “hungry”! Their last meal may have been 12 hours ago. Can you blame them. This is not normal for mammals! Normal is for them to consume numerous smaller meals more frequently and receive more that limited amounts of milk. This is the beauty of the autofeeder system. The term has been used by Foerster Technik as the feeding plan that permits ad libitum milk intake during the early preweaning period. In Europe calves are more the first 40 days of life. In the US, it frequently is shorter. Let’s not get too tied up in the “40”, but consider this as ad libitum feeding.
The 40FIT program for one dairy is shown below.
For the first 32 days in the group pen they are on the 40FIT plan. The calves are permitted to drink as much as they want, BUT they can drink no more than 2 L every 2 hours. . The 6 and 8 at start and end values is only there to show alarms if calves consume less than these amounts. Sounds just like mom? In period two during the next 4 days we reduce milk allotment from 12 L to 8 L, hold it constant for the next 10 days and then gradually reduce milk over 14 days to 2L/day
Several items to consider with this feeding plan. First, we don’t force the calf to drink large volumes of milk as we are accustomed to when using 4 L or 4-quart bottles. Soon calves learn that milk is available at nearly all hours they develop a much more relaxed feeding behavior. Some calves may consume quite a bit one day and not so much the next day. The figure below shows the feeding behavior of one calf.
Note that this calf increased its daily milk intake from 4.0 L on the first day in the group pen to 13 L and as much as 16 L by 14 days in the group pen. Note also that it has gradually decreased milk intake while still under the 40FIT regimen.
I would add that some calves may never exceed 8 L of milk and are healthy while others drink quite a bit more.
Some farms can’t quite get used to the concept of the 40 Fit or ad libitum milk program early in the calf’s life. Remember that no one is forcing the calf to drink. They quickly adapt to a more relaxed feeding behavior. It’s also best to get calves into the group pen with the autofeeder as soon as they have a vigorous appetite and not wait too long. Calves that are bottle fed in individual pens for more than 7 days “learn” to expect milk only twice a day and are a bit slow in learning a new feeding behavior.
If one wants to ease their conscience and limit milk intake early in life that is possible too as one can set a maximum intake of 12 L/ day in place of the 40FIT. Allowing more liberal milk early in life also discourages cross sucking which can be a problem if milk intake is less than 8 L/day early in life.
Give 40FIT a try and see how your calves like it.
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