New alfalfa varieties enhance milk production
The best way to boost a cow’s milk production is through her stomach. Conveniently, new alfalfa varieties that help increase digestibility have recently hit the market or are making their way through the regulatory process.
This spring, Seedway and Allied Seed began marketing N-R-Gee, an improved forage-quality alfalfa conventionally developed by Don Viands, professor of plant breeding and genetics at Cornell University.
N-R-Gee’s higher concentration of neutral detergent soluble fiber helps increase carbohydrate availability, which in turn improves protein utili-zation, explains Julie Hansen, senior research associate in plant breeding and genetics at Cornell. "Animals receive two benefits: they are able to digest the alfalfa more readily and they can eat more of it," she adds.
Research shows an average daily milk production increase of 3.3 lb. compared with feeding a check variety.
Developed under New York State growing conditions, N-R-Gee is well adapted to the Northeast and Upper Midwest. It has a fall dormancy rating of 4, producing three to four cuttings per year and a seeding rate of 12 lb. to 15 lb. per acre.
Reduced lignin varieties. Testing is also occurring on biotech alfalfa plants that have reduced lignin content.
Lignin is a primary component of cell walls, and reducing lignin content in alfalfa results in increased fiber digestibility for livestock.
"Lignin is not only indigestible, it binds with cellulose to further decrease fiber digestibility," says Mark McCaslin, president of Forage Genetics International, in Shoreview, Minn. "We believe the most logical way to improve the digestibility of alfalfa is to reduce the lignin content."
In the early 2000s, the U.S. Dairy Forage Research Center in Madison, Wis., the Samuel Roberts Noble Foundation in Ardmore, Okla., and Forage Genetics teamed up to create the Consortium for Alfalfa Improvement, a research team currently working to develop reduced-lignin alfalfa.
DuPont Pioneer later joined the group.
Through genetic engineering, the consortium discovered that silencing specific lignin pathway genes resulted in alfalfa plants with reduced lignin content and increased fiber digestibility. "We will be submitting the regulatory package to USDA within the next year, and hope to have seed on the market by 2016," McCaslin says.
Forage Genetics and Monsanto are co-developing the technology but plan for wide adaptation.
"Our intent is to broadly license this new trait," McCaslin adds. "There will be multiple seed companies selling reduced-lignin alfalfa."
Production advantages. The good news regarding reduced-lignin alfalfa is that there is no yield reduction and plant standability is not affected.
Better yet, initial studies suggest that reduced-lignin alfalfa can be cut later than conventional stands without sacrificing hay quality.
"Dairy-quality hay is typically harvested in the bud stage," McCaslin says. "Reduced-lignin alfalfa may be cut up to a week later, allowing a unique combination of high forage quality, maximum forage yield and improved stand longevity."
He anticipates there will be varieties of reduced-lignin alfalfa adapted to all regions of the country.
"Reduced-lignin alfalfa will also cut down on labor," adds Dan Undersander, hay specialist at the University of Wisconsin. "Instead of taking four cuttings, growers can take three, and they’ll get 20% more yield with three cuttings than with four."
Not only will the new alfalfa varieties benefit dairy producers making hay for their own use, but commercial hay growers will also see advantages. "Hay growers get paid a premium for improved forage quality, and reduced-lignin alfalfa should increase the likelihood of harvesting high-quality hay," McCaslin adds.