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Beef belch fact: methane equals lost profits

With proper management, farmers can produce more with less feed.

Methane production is lost money to beef and dairy producers. While the gas that's produced in the rumen of cattle, and expelled from either the front or back end of the animal, is commonly regarded as a harmful greenhouse gas, it is more than an environmental issue.

The more methane an animal releases, the more energy it is losing. It's lost feed energy that could have been used to produce meat or milk, explains Dr. Karin Wittenberg, a University of Manitoba livestock nutritionist.

"On average about two to 12 percent of total feed energy consumed by cattle can be lost as methane gas," she says. "In other words that is like losing one out of every 10 to 20 round hay bales."

Feed quality effects feed efficiency and the amount of methane produced by cattle. Supplying cattle with higher quality feed has the dual benefit of improving beef production, and at the same time reduces methane production.

Ruminant livestock, such as beef and dairy cattle, produce methane as part of the normal digestive process. Methane gas is produced as a byproduct of the fermentation of feedstuffs in the rumen. Most of this methane is expelled from the mouth and nose through breathing or belching.

"Identifying feeding practices that reduce this methane production by cattle will improve feed utilization and address environmental concerns," says Wittenberg. "In general, when animal production efficiencies are improved - through proper nutrition, management, reproduction or genetic selection of animals- the amount of feed required to maintain an animal is reduced as more feed energy is diverted to production. This means a drop in the methane per unit of meat or milk produced. If fewer animals can be maintained in the herd with improved productivity, then the total amount of methane produced from the overall herd can also be lowered."

Improved Forage Factor

That's where improved forage and pasture management can play a big role in providing livestock with higher quality forage, ultimately improve feed efficiency, and reduce methane production by about 20 percent. Similar results can be achieved whether straight grass or mixed legume/grass pastures are grazed.

Manitoba research showed beef cows grazing an alfalfa-grass stand produced 25 percent less methane than a group on a straight grass pasture. In related studies, steers grazing a grass pasture early in the season, when grass was in its most vegetative state, had 29 to 45 percent reduced methane production compared to grazing steers at mid and late seasons. From a production standpoint, weight gains by animals grazing higher quality forage were significantly higher.

Rotational Dividends

That's where a rotational grazing system can produce dividends, says Duane McCartney, a forage and grazing specialist with Agriculture and Agri-Food Canada (AAFC) in Lacombe, Alberta. His research shows the value of creating a simple three or four pasture system, that includes an early-spring, turnout pasture, which is sometimes referred to as a sacrifice pasture.

"That sacrifice pasture makes it possible to get cattle grazing earlier and takes the pressure off native grasses, or other domestic species that may not be ready until later in the season," he says.

Crested wheatgrass works well for a turnout pasture. It's an early, hardy grass that grows well under moist or dry conditions. Fertilizing the pasture in the fall will produce even better results, he says.

"The fertilizer allows you to get cattle out 10 days to two weeks earlier than if you didn't fertilize," says McCartney. "The strategy with early spring grazing with crested wheatgrass is to graze it down to the ground. This wouldn't be recommended with most other grasses, but it works with crested wheat, especially if there's added fertility to help it bounce back."

He recommends hitting the crested wheat hard, in early May for example. Grazing it to the ground will delay seed set, and that two to three weeks will give bluegrass and brome pastures time to produce enough growth for grazing in late May or early June. The crested wheatgrass often recovers enough over the spring and summer so it can be grazed again in late fall, at the end of the growing season.

Intensive Rotational Grazing

Pasture scientist Dr. Paul McCaughey's research has looked at more intensive rotational grazing systems, which involve moving cattle through pastures weekly or even daily. McCaughey is with AAFC's Brandon Research Centre.

He notes that single pasture or season-long grazing can work, but properly done it requires more management. A number of management techniques including herding, salting and watering practices need to be used to ensure proper distribution of cattle over the whole pasture to prevent cattle from "camping" on favored spots near water.

"Properly managed it can be very labor intensive," he says. "With the portable fencing available today, it may be easier to manage a rotational system."

The objective of rotation grazing is to improve harvest efficiency, and get more efficient use of the forage by livestock while managing plant energy reserves in a way that won't deplete plant energy, says McCaughey. "This keeps pasture regrowth strong and vigorous, pastures in production longer, and prevents weeds from moving in.

"The key is to keep the grass vigorous and growing and in a vegetative state," he adds. "The grazing plan needs to ensure the forages have time to put down root reserves before the end of the growing season. Plants that are continuously grazed and don't have time to store reserves before freeze up, will be less vigorous, less productive and may eventually die out, especially if they are grazed in the same manner year after year."

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