Time to cull, not skimp on feed: forage expert

Producers need to assess available hay, straw and grain and determine how to best meet livestock’s nutritional need.  |  File photo

Producers with feed shortages are advised to get rid of older or open cows and those with physical limitations

ROCKY MOUNTAIN HOUSE, Alta. — Extra planning is needed to control costs and keep cows healthy when feed is in short supply.

“If you skimp and don’t do things right on the feeding program now, it could affect the cows next year and the year after,” said forage specialist Barry Yaremcio of Alberta Agriculture.

Drought caused feed shortages in many areas this year, and although there was some recovery later in the season, pregnant cows may have to eat more straw and alternative feeds, he said at a recent cattlemen’s day sponsored by Clearwater County in west-central Alberta.

Cows will handle this challenge better if they are in good condition. Thin cows struggle through a cold winter, may have calving difficulties and may not produce enough milk.

A cow that is 200 pounds lighter than normal is missing its insulating fat cover and will need 1,400 pounds of hay to stay warm.

Cows that are in poor shape at calving may need assistance be-cause they do not have enough energy or muscle tone to push out the calf. Those in good condition return to estrus sooner than thin cows.

Producers may need to consider reducing the herd to stretch out available feed. Pregnant cows make money, and there is no point in feeding an open cow over the winter that will not produce a calf.

“If you’ve got a crotchedy old girl that wants to put you through the fence, she’s gone. If it is a 14- or 15-year-old cow, that is another candidate. Physical limitations like poor udders and poor feet are candidates for culling,” he said.

Also, consider the cow’s size. An 1,800 lb. cow eats more than a smaller one weighing 1,200 lb.

Next, figure out how much feed is available, such as hay, straw, grain and supplements.

The amount of available protein and energy is the first consideration when planning to get a pregnant cow through the winter.

Cows need seven percent protein in the ration at pre-calving, nine percent at calving and 11 percent at lactation. Energy requirements also increase as cows move from early pregnancy to lactation.

Most good hay contains 58 to 60 percent energy, so no grain is needed until after calving.

Producers who feed straw should add six to eight lb. of grain per day, four ounces of limestone, an ounce of magnesium oxide and trace mineral salt to keep the cows going.

“I feel there should be very little or no straw in an after calving ration,” he said.

“It is too low a quality with not enough energy, not enough protein. If your cows lose weight, they won’t milk properly,” he said.

It takes seven lb. of milk to produce one lb. of gain for a calf.

“If you don’t have good body condition score, she can’t produce that amount of milk at the peak, therefore you are losing that same amount of milk throughout the 250 day lactation,” he said.

Producers who are trying to stretch out feed supplies should consider how much is wasted.

Stacking bales in a pyramid is probably the worst way to store hay because snow and water seeps in and could cause spoilage. The best type of storage, if there is room, is to place single bales in rows 15 to 20 centimetres apart.

Feed waste also comes in other forms.

A bale processor could be responsible for 19 percent feed waste, while an unroller causes 12 percent loss.

Three to 20 percent waste is attributed to bale feeders, depending on the design.

Yaremcio said the outside of the bale feeder should have rods 35 to 38 cm apart at a slope so the cow has to turn its head to get in. Feed that is dropped will fall into the feeder rather than on the ground, where it is trampled.

Silage on snow causes 25 percent feed loss, so putting feed in tubs or some other container will keep cows from walking over spilled feed.

Feeds of all types should be tested for nutrient quality and sulfur and nitrate levels.

Many crops germinated in July this year and were in full bloom in September. As a result, more was turned into green feed or silage. It was a good choice because cows like it and it contains 14 to 16 percent protein.

However, nitrates and sulfur levels need to be monitored because cows could end up with polio and die if sulfur levels are too high.

There should be no more than seven percent oil if pods are starting to fill. Otherwise, the rumen does not function properly.

Crude protein may be unavailable to an animal if green feed or hay was put up tough. It may smell sweet or similar to tobacco. Green feed bales that are heated to more than 40 C will convert nitrate to nitrite, which is toxic.

Pea straw is high in protein, but cows take a couple days to adjust to the taste. It could be mixed half and half with cereal straw to boost nutrition.

Weeds such as kochia can be fed, but they might accumulate compounds that limit calcium absorption.

Other weeds can accumulate nitrates and alkaloids, which is the same kind of toxin as ergot. For safety’s sake, limit this kind of feed to 20 to 25 percent of the ration.

Reed canarygrass is a potential feed, but some varieties have high alkaloid content early in the year and may kill cows.

Some farmers cut parts of fields this year that they did not usually use and ended up with water hemlock or sea side arrow grass in the hay mix. These contain cyanide and can kill a cow in 30 minutes.

Grazing stubble is always a good option, but cows can overload on grain if too much is spilled in the field during harvest. Cows should also receive high levels of calcium supplements.

Grazing perennials such as alfalfa is a good idea as long as the crop is dormant. Many producers turn cows out too early while the crop is still growing, which can result in winter kill.

Supplementation is also needed to make sure cows receive essential minerals such as calcium and phosphorous. Trace mineral deficiencies reduce immune function in cows and calves. Deficiencies may also affect fertility and calf growth.

Calcium may be delivered by adding limestone. However, it is chalky and dries out the mouth, so it is not palatable to the animal. Adding six to eight lb. of dried molasses to the mix sweetens the feed, and the cows are more willing to eat it.

However, adding molasses to improve straw intake is probably not worth doing.

“Straw intake is limited by the intake of neutral detergent fibre,” Yaremcio said.

“Putting molasses on it may alter the taste a little bit, but their total feed intake per day will not change.”

Neutral detergent fibre is a measure of lignan, which is hard to digest.

Producers might consider using an ionophore such as rumensin or Bovatec in a year like this one to improve digestive efficiency, especially if cows are on a high fibre diet.

Remember that these products can kill horses and dogs, so they should be used with care.

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