Nutrition needs to be vital part of winter feeding

A beef specialist urges producers to test their feed, especially in a year like this when forage crops are lower quality

CARSTAIRS, Alta. — Nutrition and animal performance go hand in hand.

This year forage crops have lower energy and protein levels so rations may need extra attention to ensure livestock are properly fed, said Barry Yaremcio, beef specialist with Alberta Agriculture.

Feed testing is necessary to assess moisture levels and quality and determine where supplements are needed.

Accuracy of samples and tests are important. If samples are collected by hand, pieces of the feed may be lost along with their nutrients and won’t register in the test. Consider using a tool to collect core samples.

Yaremcio recommends requesting a wet chemistry analysis for mineral assessment because it is more accurate than near infrared spectrometry. NIR consists of wavelengths of light bounced off the feed, and calibration curves are used to measure what is there. It is an accurate test for protein and fibre levels, but not worthwhile for minerals analysis.

Protein, calcium, phosphorous, magnesium, potassium, sulfur and sodium are the basics of a good ration.

“Without that I can’t put a good ration together. That is the minimum,” he said at a cattle clinic held in Carstairs on Sept. 19.

The test should also show acid detergent fibre levels.

ADF is used to calculate the energy density in a feed. Neutral detergent fibre is used to determine how much of it cattle will consume on a daily basis. If that fibre is up to two percent of their body weight, the cattle will be filled up. It takes time to digest and there is less room for them to eat other things, said Yaremcio.

Bales that are too wet may smell like tobacco and protein levels are reduced.

Nitrate levels in feed may rise after a hailstorm or light frost. A field that received a lot of nitrogen or areas with continuous swath grazing and lots of manure may also result in a nitrate overload.

Yaremcio said cover crop fields containing lots of brassicas should be tested for sulfur accumulations. If there is more than 0.4 percent sulfur in the ration, it changes to sulfuric acid in the cow’s rumen. The acid kills the bacteria responsible for consuming thiamine or other B vitamins.

“Without thiamine, you get a swelling of the brain and you get polio and dead animals,” Yaremcio said.

Low protein in the feed will reduce the amount of fibre cattle can digest and lower their intake.

Consider the cost of protein per tonne and amount of protein in a given feed. Feed may be cheaper by the tonne but if it has less protein there is reduced benefit.

Varying amounts of protein may be found in corn distillers grains, wheat distillers grains, barley malt sprouts, urea, lentil screenings, peas, screenings and stillage.

A lot of byproducts may have good protein, but they are low in calcium and high in phosphorous, said Yaremcio.

Getting protein into cattle can be a challenge because it is hard to know if they are actually eating it when licks, tubs or blocks are offered. A 1,400 pound cow in late pregnancy requires 1,346 grams of protein per day.

“If you have no practical way to supplement with grain or hay, use a block or a tub,” he said.

Protein is short later in the grazing season when the grass is overly mature. Yaremcio advised producers to monitor cow body condition as well as manure quality and structure. If the rumen is working properly, the manure should be a flat pad but if there is not enough in the diet, the manure will pile up like a pyramid.

Online calculators are available to see how well a feed meets an animal’s needs. The Beef Cattle Research Council offers a spreadsheet to show whether feed is meeting requirements or is deficient in some area. It can be found at www.beefresearch.ca/feedtesting.

Calcium and magnesium supplementation is required in most straw-grain grass hay or cereal silage rations. Consider adding dried molasses to limestone mixes to improve intake. Limestone can dry out the mouth and phosphorous is bitter so molasses can be added until intake improves.

If the cattle are getting legumes like alfalfa, clover or vetches as well as canola, higher levels of calcium are available so less supplementation is needed.

Minerals like selenium, copper, manganese and zinc are deficient in most parts of Alberta. Cobalt and iodine are not present in Western Canada so supplements are needed.

Cows can keep warm by the feed they are digesting, said Yaremcio. The critical temperature for cattle with a good hair coat is -20 C. Add two pounds of grain per head per day for every additional 10 C drop in temperature at noon.

For example, at -20 C cattle need four lb. of grain and at -30 C they need six lb. to keep warm.

“Watch your weather forecast. If you see the weather is going to modify in the next day or two knock back that grain. If you are feeding eight pounds of grain and it chinooks, those cows will be heat stressed and they will back off feed,” he said.

Ideally calves should be fed up to 450 lb. before winter sets in. They cannot eat enough to keep warm when they are smaller.

Yaremcio said producers should consider creep feeding those that need to gain. Whole peas and cereal grain for small animals can be offered but once they weigh more than 700 lb., the kernel needs to be cracked.

For two lb. of gain on a feeder animal, feed one percent of grain per bodyweight. A 700 lb. animal would thus get seven lb. of grain.

Rumensin in the diet to guard against coccidiosis is a wise investment, said Yaremcio. However, it should not be fed free choice. It needs to be mixed and should not be spread on the ground because it can kill dogs and horses.

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