North Central Montana Sheep Seminar

By Lisa Schmidt

Profitability comes a little easier this year for sheep producers, with both lamb and wool prices at record highs and still climbing. But production costs can easily wipe out even the highest market prices so specialists from the Montana Sheep Institute recently talked strategy to about 40 Conrad, Montana area producers.

Dr. Lisa Surber, who manages the Montana State University Wool Lab, predicted these high prices are likely to continue for the next three to five years.

Surber pointed to three primary reasons for rising lamb prices: low supplies for lambs throughout the world, an Australian dollar on par with the U.S. dollar that favors exports and discourages imports and increasing demand from Muslim and Jewish communities in the Midwest and along the East Coast.

Increasing demand for wool products such as washable shirts and underwear, and a decrease in worldwide supply of wool because many producers are shifting to meat-type breeds have pushed wool prices skyward.

Both Surber and MSU Extension Sheep Specialist Rodney Kott agreed that the price difference between fine and coarse wool would continue to spread, with a premium for fine wool and fewer opportunities to sell coarse wool.

That’s good news for U.S. sheep producers. While China produces most of the world’s wool, about 85% of China’s clip is coarse. In the U.S., 20% to 30% of the national wool clip meets the criteria for fine grades.

Grazing reduces weevils

But even with rising prices on the marketing end, producers still need to reduce production costs.

MSU research scientist Hayes Goosey offered a win-win solution for sheep producers who have irrigated alfalfa fields.

Montanans harvested about 1.7 million acres of alfalfa in 2009, yielding about $360 million of hay. Much of that yield was from irrigated land where alfalfa weevils thrive, eating the most nutritious portions of the alfalfa, leaving the stems and leaf veins for livestock.

The alfalfa weevil damages Montana’s largest forage crop every year, but spring sheep grazing can disrupt the parallel cycles of the alfalfa plant and weevil to reduce weevil damage by 40% to 70%. After grazing, the alfalfa recovers quickly and gets a jump on the weevil larvae.

In fact, Goosey’s research indicates that a producer can graze between 100 and 230 sheep per acre on alfalfa in the spring and still harvest the same yield.

“Harvest will probably be delayed for a week, but you should get the same yield,” Goosey said. “And, you get the yield from grazing sheep, too.”

Grazing timing matters.

Varying climates mean green up arrives on different dates, but the number of degree days is consistent across regions. Both alfalfa and weevils need temperatures between 9 degrees Celsius (48 degrees Fahrenheit) and 31 degrees Celsius (88 degrees Fahrenheit) to grow in the spring. Both the plant and the weevil accumulate heat to keep growing and scientists measure that accumulation of temperature over time in Degree Days. Goosey recommends grazing sheep on alfalfa fields prior to 34 degree days.

“Graze the sheep until at least 106 Degree Days and quit before 150 Degree Days,” Goosey says. “Producers can calculate degree days online, by using their local weather station information and a degree day calculator at http://uspest.org/wea/. Just be sure to use Celsius temperatures in the calculator.”

New parasite control recommendations

Sheep producers have known for a long time that managing internal parasites is another way to reduce sheep production costs for a big pay off.

In the arid West, many producers worm their sheep in the spring and fall, while eastern producers run their sheep through the chute for a dose of wormer at least four times a year, with many targeting parasite control every two weeks.

That frequency, plus under-dosing, has allowed internal parasites to develop a resistance to the most common worming drenches on the market.

“We don’t have much of a problem with resistance out here, but those guys back East are running out of options,” says MSU’s Kott. “We don’t want that to happen here.”

Kott and his cohorts in other states recommend a revised worming strategy that should treat internal parasites more effectively and reduce the chance of developing resistance in parasites.

First, when calculating the dose to administer, instead of dosing for the average weight of the ewes in the flock, calculate the dose for the heaviest ewe.
“The extra dose won’t hurt your flock and you are less likely to under-dose,” Kott says.

Second, time drenching with the parasite’s life cycle.

Most parasites go into a hibernation-type phase in the winter.

“No matter what you do, you can’t kill them when they are in this stage,” Kott says.

The parasites emerge from this hibernation in the spring so producers should consider drenching each ewe about two or three weeks before lambing.

“Practically, this means at shearing or in the lambing jug,” Kott says. “If it’s a long, wet summer, you might worm again in August, but usually you only need to worm once a year.”

Third, rotate among the three most common classes of wormers. Kott classifies wormers into Levamisoles — the clear drenches, Benzimidazoles — the white drenches, and the mectins such as ivermectin and cydectin.

“Every third time you worm, use a different class of wormer and then you can go back the next time,” Kott says.

Fourth, rotate pastures. Parasite larvae can survive on pasture for up to 90 days in the summer and 180 days in the winter. Once sheep graze a pasture, stay off of it for at least 21 days, Kott says.

The North-Central Sheep Seminar in Conrad was sponsored by MSU Extension and the Montana Sheep Institute. The Montana Sheep Instititute is a partnership between MSU Extension and the Montana Wool Growers Association.