Cover crops can fulfill nutritional needs for sheep
Cover crops not only benefit sheep as a secondary feed source, but they can also be used to flush ewes, according to a North Dakota Extension specialist.
Rick Schmidt said producers who want to raise a cover crop for sheep to graze should look for something affordable that meets their objectives.
North Dakota State University (NDSU) researchers planted 11 different cover crops to determine which plants sheep would seek out to graze. Included were brassicas, like turnips, radishes, red clover and hairy vetch. Sorghum, millet and sunflowers were also planted.
“We planted them with alfalfa to determine if the alfalfa could be established after the cover crops in a one-pass seeding,” Schmidt explained. “It worked out quite well.”
Once the crops were established, the sheep were turned in, and Schmidt said they grazed the radishes, turnips, red clover and hairy vetch, even before the alfalfa.
“They left a lot of the grasses and even walked a lot of the grasses down,” he said. “We found sheep like the lush, vegetative, broadleaf plants, while cattle prefer millet, sorghum and sunflowers.”
Schmidt said the brassicas are very nutritional to sheep.
“There is a tremendous amount of nutritional value in those plants, and they can really be beneficial in flushing ewes before breeding,” he explained.
However, producers will want to use caution when they graze the ewes on cover crops prior to breeding. If the ewes are turned into the cover crops too early, they may get too fat, and it will be hard to get them to flush, Schmidt said.
Some plants contain phytoestrogens that can prevent the ewes from breeding after two cycles.
“The phytoestrogens can build up in time causing a reduction in conception rates. If the ewe isn’t bred by the second time she cycles, this could be the problem,” he explained. “The phytoestrogens don’t pose a problem for ewes once they are bred.”
Cover crops could be used to feed sheep year-round from a nutritional standpoint, Schmidt said, but the plants have such high nutritional value, producers will have to see what they can do to get the ewes to flush at breeding.
“Thin ewes are always easier to breed than a fat ewe,” Schmidt said. “Thin ewes can be turned out on a cover crop, and they should breed instantly.”
These cover crops can also make good feed through the winter months.
Brassicas won’t freeze until it gets below 10 degrees, and radishes and turnips will keep growing through the winter months. The plants will all maintain relatively high nutritional value late into the winter, Schmidt said.
However, producers may want to have a backup plan, Schmidt warned, in case the cover crops are buried in the snow too deeply for the sheep to reach.
Schmidt recommends cross-fencing the cover crops with some type of fence, like electronet, to get better utilization and less trampling of the cover crops.
“It is also important to have a good watering system in place,” he said. “I like utilizing cover crop grazing for sheep.”
“If you can get six inches of growth, I would consider the cover crop a success. Six inches will provide 2,000 pounds of biomass per acre,” Schmidt said. “The sheep can graze off 50 to 60 percent of it and still maintain soil health while providing a secondary food source for the sheep.”