Feeding a protein supplement maintains animal performance
About every year there are periods when the forage on hand isn’t high enough quality or in adequate quantity to meet your cow herd’s needs. You can’t be sure just which time of year, but you can count on challenges from pasture dormancy, drought, pest infestations, blizzards, all things that can make you operation short on the energy component of feed.
Of course, as a beef producer, it warms your heart to see cows out making a living grazing forages—just turning grass into beef without interventions from management or your checking account. But that warm heart sometimes gets in the way of cold business sense. You will usually benefit economically by correcting nutrient deficiencies sooner than later. For example before you begin to see body condition losses. Doing so substantially improves animal performance. And poor animal performance gets into the checkbook, too. Poor performance from a deficit in energy for your herd leads to decreased conception in cows; reduction in milk production and lactation length; loss of body condition scores; and reduction in fetal growth.
It can also bring on a reduced tolerance to stress, which invites disease, parasites and calving challenges.
Addressing forage/energy deficiency can be tedious. A straightforward solution is to feed a supplement which is low in protein and high in energy. Corn, for example. You can supplement the additional energy in a number of ways: tubs, blocks, liquid, cubes, pellets, mash, etc.
Your cost will vary. And your herd’s potential for shrink and the ease of handling will vary. Fundamentally the objective is to get supplemental feed that directly addresses the limiting factors in the cows’ diet. Of course, you have to consider your labor costs, time and delivery options. These are too often ignored to the detriment of your payday. Still, if you study the economics of these factors are combined with the a range of feed nutrient values, you can find the best value for the money. For example, a 20-percent protein hay might have a lower unit-of-energy cost and/or protein cost than a supplement tub. But, if you are driving 50 miles to do chores, tubs make a lot of sense.
Also consider how the cows will handle the diet. Ruminal forage digestibility can be reduced when high starch levels are introduced to the diet.
Fiber digestibility increases as an all-forage diet increases in starch. Fiber digestibility reaches a peak/plateau at about 0.25 percent of bodyweight. If you are feeding corn, that means feeding 0.375 percent of body weight to get to the right spot. At higher levels, the energy concentration increases, but the fiber digestibility declines. At ever higher levels of grain, this becomes less of an issue because the amount of forage in the diet is dropping.
However, one concern with lower forage digestibility is that the rate of passage through the animal will take a lot longer.
In turn, the rumen fills with forage that can’t be pushed through the system fast enough for adequate forage to be consumed. You can help the process by mechanically chopping the forage.
Another constraint to forage digestibility can be a forage with a low crude protein content. When forage protein is below 8 percent, the protein/nitrogen in the rumen can limit rumen bacteria growth, which in turns limits forage digestibility. The rumen microbial population needs adequate nitrogen to function well. They get that nitrogen from protein/nitrogen feeds. Therefore, adding a protein supplement to the diet can increase forage intake in many cases and alleviate or reduce the energy deficiency problem. This is particularly the case where your forage inventory is abundant but slightly high in fiber and low in protein. Controlled studies indicate that the intake of lower quality forage can be increased 20 to 60 percent, and forage digestibility can be increased by 5 to 15 percent by supplementing rumen-available protein.