Make sure alternative forages contain adequate nutrients
For livestock producers facing hay shortages this winter, finding alternative forages is not as much of a challenge as providing feed sources with adequate protein and energy for overall ruminant health.
Francis Fluharty, an Ohio State University animal sciences researcher, said that maintaining a high-protein, high-energy combination can be achieved. It just takes a bit of juggling to get the right nutrient balance.
“We have several sources of alternative high-energy feeds such as corn, distillers grains and pelleted soybean hulls. However, the prices of these are going up rapidly. Additionally, many producers do not have the facilities to store distillers grains or soybean hulls,” said Fluharty, with the Ohio Agricultural Research and Development Center. “This has led many people to turn to corn stover or even soybean stubble bales as a primary source of feed. However, neither is high in protein, so a readily digestible protein source must be supplemented if these feeds will be used.”
Cattle need adequate protein to grow, mount an immune response, reproduce, maintain a pregnancy, or give birth to and nurse a healthy calf. Adequate protein supplementation also facilitates the digestion of feedstuffs.
Feedstuffs, such as corn stalks and soybean stubble, are also high in lignin, an indigestible complex chemical compound that gives strength to plant cell walls. The higher the lignin content, the harder it is for a ruminant to digest the feed.
“Two things must happen to aid in the digestion of low-protein, high-lignin feeds. Adequate supplemental protein must be provided, and the particle size of the material should be reduced,” said Fluharty, who also holds an Ohio State University Extension appointment. “If low-protein feeds that are high in lignin such as straw, corn stover, and soybean stubble are not chopped and supplemented with appropriate sources of protein, then animal performance is reduced.”
If producers are using corn stover, baled soybean stubble, straw or similar low-quality forages as a feed, the following are some key points to remember:
* Dry beef cows will need a diet that is 8 percent protein in the middle third of pregnancy and 9 percent protein in the last third of pregnancy. Pregnant yearling heifers will need a diet that is at least 11-12 percent protein, and heifers and cows nursing calves will need a diet that contains at least 12 percent protein.
* If heifers and young cows are not separated from older cattle, they may be pushed aside when given supplemental feeds, and they may not receive the protein or energy they require.
* With low-quality feeds, it is best to feed combinations of ruminally available (urea, soybean meal) and ruminally escape (corn gluten meal, distillers dried grains, fishmeal) protein sources.
* Soybean meal is an excellent protein source with low-quality forages, because approximately 80 percent of the soybean meal is degraded in the rumen, and the rumen microbial population must be given a source of nitrogen so that they can reproduce, before they can digest the low-protein forages.
* If you are using corn stover, straw, or baled soybean stubble as the main source of forage, it may be necessary to supplement a high-energy feed to your cattle such as dried distillers grains, corn gluten feed or pelleted soybean hulls in order to keep the animals in the proper body condition.
* If labor is an issue, and it is not feasible to feed protein supplements daily, it might be appropriate to use protein tubs or protein kegs for supplementation with low-protein feeds such as straw, corn stover, or soybean stubble. However, expect to pay two to four times more for the same amount of protein than you would have paid if a soybean meal and distillers dried grain combination had been used as a top-dress.
* Keep in mind that the mineral nutrition of your cow herd should not be compromised due to the need to purchase additional feed. Having a good mineral program will enhance performance, allow the animals to convert energy more efficiently, improve calf survivability and growth, and reduce the post-partum interval from calving to rebreeding.
Fluharty said that when deciding what types of feed to provide to livestock based on costs, calculate the feedstuffs based on price per pound rather than simply comparing bushel price.
“For example, comparing corn to bale price of stover, if corn is $3.36 per bushel, it’s 6 cents per pound. If a 1,000-pound bale of stover costs $30, it’s 3 cents per pound. However, the net energy for maintenance of stover is only 51 percent of that for corn. Therefore, on an energy basis, they cost the same,” said Fluharty. “However, the net energy for corn grain is 2.7 times higher than that of corn stover, making corn a more economical energy feed for grain. And if corn has a digestibility of 95 percent and corn stover has a digestibility of 55 percent, which one is a better source of energy?"
For more information on forages, refer to the Ohio State University Extension Beef Team newsletter at http://beef.osu.edu .