With the grass so washy for much of the Midwest this year, there are some herds with the cows looking a little thin. Since the calves have been weaned, now is the best time to start putting weight back on those cows.
For those of us here in the Midwest, those who didn’t have most of our fields in prevent-plant, the question is why would we want to accomplish this on cornstalks?
Here's the reason why: This is the best timeframe to add those pounds because we know, just like the old saw says, winter is coming. After the brutal winter we had last year, it should have taught us we cannot wait until January to start to put weight on cows. There are two reasons: The first is that in sub-zero artic weather, the cow has difficulty eating enough to maintain her weight and stay warm, let alone add pounds. The second has to do with the concept of fetal programing.
Fetal programing is where the nutrition and environment the calf receives inside the cow corresponds to their performance later in life. An example of this comes from a research article published by Dr. Min Du in the December 2014 Journal of Animal Science. It reported that a restriction of nutrition to cows during early to mid-gestation led to decreased numbers of adipocytes (fat cells) in the offspring within their muscles. This meant there were less adipocytes to create marbling when the calves were finished, thereby making them grade lower on the rail. Therefore, cows that stay thin through the fall on stalks, which is typically mid-gestation for most beef producers, will create calves that will not finish to their genetic potential.
Plan your grazing
Traditionally we like to think of stalks as a cheap feed source to sustain the cow until the snow gets packed or the ground becomes icy. But if done correctly, and possibly with a bit of supplement, cows can gain back lost pounds during this grazing period. However, adding this weight will require some planning.
There is a feeling out there among many cattle producers that cornstalks are not quite as nutritious as they were ten years ago. The only way to know for sure what you have in your stalks is to test them prior to turnout. Focus on just the leaves and husks, as the goal with gaining weight on stalks is to move the cows when they have eaten the corn and half the leaves and husks. If protein is low, which it will likely be, then we will need to strategically supplement protein while they are grazing. However, energy should be good.
Next, look at your cow’s body condition score. A great time to do this is while preg checking. If possible, sort your low BCS cows from the good condition animals and place them on the richest stalk field. Be careful that there isn’t too much corn on the ground that we can cause acidosis—if this is the case sub-divide the field with electric fence and graze one paddock at a time.
When to move
As stated above, the goal is to move cows when they have consumed half the leaves and husks on the field. For rough math, there are usually 16 pounds of leaves and husk to the bushel of corn. The University of Nebraska has a corn stalk grazing calculator that can be used to calculate the timing of the move. However, if we are looking to add weight to cows, a simple option is to move them when you stop seeing kernels of corn in their manure. This cleans up the volunteer corn and keeps the cows on a higher-energy diet for gaining weight.
Of course, all good things must end, and the same comes with cornstalk grazing. Once we’ve removed 50% of the leaves and husks from all the fields, then we need to get those cows off the field and onto a different ration. Cows can go backward if left with insufficient nutrition on stalks in January or February. Whatever that ration will be, prepare to move the cows at the moment nutrition dictates the timing.
With the tough hand Mother Nature has dealt us this past year and the prospect that it could be difficult in the upcoming winter, there’s no reason to delay putting weight on cows. Use cornstalk grazing to your advantage to up their BCS so the cows are more prepared to handle the winter.