Low-Quality Hay, High-Quality Results: Getting More from Forage in Angus Herds

Every farm ends up with some low-quality hay: late-cut, rain-damaged, or grown on thin soil. Throwing it away is expensive, and feeding it with no plan can cost you in thin cows. The good news is that a mature, dry forage can work for a beef cow if you know what it lacks and fix only that. This guide covers how to evaluate it, how to supplement it, and how to waste less of it.

Start with a forage test

You cannot judge hay by looks. Color and smell tell you something, but only a lab test tells you crude protein and energy. NDSU Extension advises laboratory analysis of all available forage before picking a supplement, and says mineral analysis, although it costs extra, can help choose a mineral. The test tells you what to buy and, as important, what not to buy.

The two thresholds that matter

NDSU gives two rules of thumb. First, when forage crude protein falls below about 7 percent, microbial fermentation in the rumen slows, which lowers digestibility and intake. Second, when total digestible nutrients fall below about 50 percent, the forage does not supply enough energy for most livestock. These are not hard cliffs, but they tell you where trouble starts.

The mechanism is worth understanding. Rumen microbes digest fiber and produce much of the energy the cow uses. If the forage is short on protein, the microbes are starved and work slowly. Cows then eat less because feed moves through the rumen slowly. As plants mature, lignin protects fiber from microbes. Utah State University Extension points out that intake rises with forage quality, ranging from about 1.55 percent of body weight at 42 percent TDN to 2.35 percent at 67 percent TDN, as given in its winter supplementation article.

Fix protein first, if protein is short

If the test shows protein below the threshold and energy is moderate, protein supplementation can lift intake and digestibility together. USU reports that supplying protein can raise dry matter intake by about 20 percent, and that if forage TDN is around 50 percent or higher and the cow is in decent condition, protein often corrects most of the energy deficit.

NDSU says a true protein supplement should be about 25 to 30 percent crude protein, and lists good-quality hay, oilseed meals and byproducts such as distillers grains and corn gluten feed as options. Non-protein nitrogen such as urea is cheap, but NDSU notes it is less efficient with low-quality forage and gives limits on how much to feed. USU suggests urea-based NPN should be no more than about one-third of total dietary protein. Read the tag, and follow the limits.

Add energy when energy is short

If TDN is below about 50 percent, protein alone will not do it. NDSU lists high-starch grains, fiber-rich byproducts such as soybean hulls, wheat midds and beet pulp, or high-quality alfalfa. A caution: feeding starch above about 0.4 percent of body weight can reduce forage intake, because the rumen shifts away from fiber digestion. Fiber-based energy feeds avoid much of that problem, so they tend to suit a forage-based diet.

Match the diet to the stage

NDSU reports that protein and energy requirements rise 15 to 20 percent from mid-gestation to late gestation. Hay that carries a cow through mid-pregnancy may fall short a few months later. Test, then re-test as stage changes, and put your best hay with the cows that need it most: first-calf heifers, thin cows and late-gestation or lactating cows. Mature cows in good condition can often use the poorest hay.

Cut waste, because poor hay wastes more

• Use feeders or hay rings, not open ground.
• Offer what cows will clean up in a day or so, because Missouri Extension's cow nutrition guide notes that daily feeding reduces waste compared with putting out several days at once.
• Store bales off the ground and under cover.
• Grind or process very coarse hay only if the cost is less than the waste.

Missouri's guide plans on about 33 pounds of hay per cow daily with 15 percent waste. Your numbers will differ, but the exercise of writing them down shows where the loss is. Our winter feeding guide shows how to adjust for cold.

Do not forget vitamins and minerals

Dry, weathered forage is low in vitamin A, and NDSU gives requirement figures and warns that vitamin potency can fall as much as 25 percent after three months of storage. Check manufacturing dates on supplements, and use a mineral suited to your forage. See our guide on supplementing beef cows for more.

Know when to say no

Some hay is not worth feeding, such as moldy hay, hay with toxic weeds, or hay so poor that the cost of supplement exceeds the price of buying better. Do the arithmetic: cost of hay plus supplement per cow per day, against the cost of a better hay. Farm.fm's page on pasture management for Angus herds shows how better pasture can reduce the amount of hay you need at all, and agriculture.directory helps you find a local lab or extension office.

The takeaway

Low-quality hay can work, if you test it, find what it lacks and fix that one thing. Confirm numbers with a local nutritionist, since they depend on cow size, stage and weather.