Growing Beef Newsletter
September 2025, Volume 16, Issue 3
Starting calves on feed – the end in mind
Garland Dahlke, IBC research scientist
A new home, a new menu and new health challenges are what all calves face when being started on feed. In this article, we will focus on the second aspect - a new menu. To start things off, on arrival it has been a long-standing practice of providing long stem hay. Not a bad idea since it is a safe and seemingly therapeutic feed for cattle, but don’t use junk. CRP hay (weeds), ditch hay, stuff that was rained on or made at a late maturity really does not help the cause for animals on arrival. Use your better forage, (note the word "forage" rather than roughage) and also note that the younger the calf, the more critical it is to use higher quality forage since we do want to provide nutrition rather than just something to chew on.
Now, taking this a step further, do not just limit these calves to only hay at arrival. We need to provide more substantial nutrition and generally young calves need and respond well to good protein nutrition. With the abundance of higher protein feeds such as distillers grains, gluten feed and soybean meal in Iowa, these natural protein sources with minimal starch and high in digestible fiber become a very good addition to the arrival diet without much threat of digestive upset. Supplements containing urea really are best to be withheld from arrival. Urea/NPN does take some further adjustment and an abundance of readily fermentable, nonstructural carbohydrate which arrival diets do not and should not have. Should we get concerned that withholding this NPN may also mean withholding mineral as is often the case where we might be using a liquid or dry supplement that contains NPN plus mineral and vitamins? My answer is “no.” The animals will be fine for a couple days without it. We may want to provide salt however, and if we strategically put the salt lick near the water source we may encourage a better, more effective rehydration after a long haul.
Next consider silage. If you are planning to feed silage or haylage later, start it now. Here I also need to qualify that we do not want to feed junk, or in the world of silage, if it is more like compost it is not good feed and should be left out. Good silage and haylage however make the arrival diet more enticing and can provide a higher level of nutrition than just hay. From a rumen standpoint note that it takes around three days for the microflora of the rumen to start changing over to a new feed ingredient. So with an arrival diet we would be looking to feed it for about 3 to 5 days and using the time as an opportunity to adjust the animal in a gentle way to the feedstuffs they will be getting over the long haul, apart from the high energy starch, sugars or oils found in the final finishing diet in order that when we do add these high energy feeds we already have many of the ingredients already in place.
The next aspect to consider is that we are also teaching these new arrivals how to eat. When bunk space is plentiful and all the calves in a pen come and eat together is preferred, but in reality, they may not or can not. This is especially the case with confinement buildings where maybe 1/3 of the calves can fit at the bunk at a given time. In these situations, we need to supply enough feed in order that all the calves can eat. But if we limit feed the diet, the aggressive calves will fill up and the rest will go hungry to some extent. Our arrival diet needs to allow the calves to eat to satiety without causing them to get sick. This generally means keeping the highly fermentable carbohydrates (starch, sugar) to a minimum initially. After the 3 to 5 days period of an "all you can eat buffet" that is composed of a digestible fiber and adequate protein, aggressive eaters tend to become satisfied and much less likely to over indulge while the more timid calves tend to learn to eat from a new bunk and become satisfied nutritionally. At this point we have the calves set up to succeed. The normal finishing rations can be introduced and we can progress as normal.
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