April 2017
Feeding Facts

Spending Time With Replacements

Spring is finally here and, hopefully, warm weather and ample precipitation have pastures growing at their maximum. Hay fertilization is just around the corner and the battle to control weeds is upon us. Also, the weaning of fall calves is just around the corner.

For purebred operations, this is a time to select bulls to be grown for breeding stock and heifers to fill the bill as replacements. Selection is always a grueling task requiring careful evaluation of several traits. Combine this with evaluating each animal’s EPDs and pedigree, it is a task that seems nearly impossible. After making selections based on animals’ phenotype and genetics, operations have to wean, vaccinate and get the cattle on feed. Thus, more stress for the manager.

Let’s at least try to simplify the latter. Weaning is a crucial time and can dictate the success managers will have getting animals adjusted to feed. After calves are pulled from the cows, it is imperative to get them on some good quality hay as soon as possible. These calves have been eating hay throughout the winter. Their rumen bacteria are acclimated to this type of feedstuff. If the calves have been on creep feeders, the same feed can be fed during this process as they will already be accustomed to this ration. Because of the stress of being separated from the cows, I recommend starting weanlings on free-choice hay and 1-1.5 percent of their body weight in feed.

If the calves have been on creep feed, keep them on the same feed. If the calves haven’t been on creep feed, start them on a feed like CPC Jump Start. Again start them on about 1 percent of their body weight. The cattle need to stay on this program for approximately 14 days to acclimate them to their new way of life. If the cattle seem adjusted after this 14-day period, it’s time to start gradually increasing their feed. During this process, remember hay is your friend; so keep plenty of free-choice hay and clean, fresh water in front of the cattle at all times.

After 21 days, it is time to start progressing the cattle to the diet they will be fed during their growing phase. This diet should be around 12 percent protein and 65-72 percent TDN. This is a good, moderate energy diet with adequate protein. Make sure the feed contains proper amounts of macronutrients and trace minerals to support proper development. I also recommend it to contain an ionophore because it seems to help with digestive maladies.

Feeds such as CPC Grower and CPC Developer will fit this phase of animal development. Grower works quite well after the 21-day adjustment. It has a nice balance of protein, energy and fiber, and works well when fed free choice to cattle up to about 800 pounds.

For heifers, it provides enough nutrients for them to grow, but generally not enough energy to get them too fat.

For bulls, however, Grower can lack enough energy to push them to weights above 800 pounds. To push bulls to higher yearling weights, managers need to switch to Developer. Developer fed at 2-3 percent of body weight can produce nice growth for higher weights. Feeding bulls based on their body weight can help compensate for their increasing maintenance needs as they reach higher weights and still provide added nutrients for growth.

Feeding replacement bulls and heifers requires constant evaluation of growth and body condition. Heifers that get too heavily conditioned during the growing phase tend to not breed as readily and usually don’t milk as well as cows. On the other hand, studies have shown that undernourished replacement heifers tend to have less longevity in the herd and problems rebreeding.

The same can be true of developing bulls. Those that grow too fast and get too heavily conditioned stand a greater risk of having structural and foot problems. Both of these problems can affect their ability to breed and decrease their longevity as herd sires.

So in a nutshell, bringing cattle along at moderate growth rates seems to be the ticket when producing replacement cattle that perform and remain in the herd for longer periods of time. As you start the next replacements out, plan to spend time monitoring their development. Also plan to feed them properly with a quality ration. Your time and money will be repaid with proper replacement development.

As always, if we can help during this important time, give us a call. We’ll be glad to help navigate you through this time and help you develop some quality replacements.


Stephen Donaldson is AFC’s animal nutritionist. If I can help any of you, please get in touch with me and let’s succeed together. You can reach me at 256-476-5272 or This email address is being protected from spambots. You need JavaScript enabled to view it..