Alfalfa hay is traditionally a staple in dairy rations. Common knowledge dictates it is included for the protein, structural fiber and palatability it brings to the dairy ration.
For dairy farmers who don’t grow their own hay or have to purchase most of their supply, quality alfalfa hay can be one of the biggest feed expenses, but not one that’s easy to reduce without damaging production rates as well.
Peter Robinson, dairy nutrition extension specialist with the University of California – Davis, says dairy consultants have tried for years to find ways to take alfalfa hay out of the dairy ration. He says from 2010 to 2013, when the dairy industry was struggling, consulting nutritionists tried without success to construct a good dairy ration without using alfalfa hay in an effort to help farmers cut their feed costs.
“They really attempted to move alfalfa out of the ration because it was a really high cost, but the feedback was always that it had a negative effect on animal performance,” he says.
Robinson says the price of quality dairy hay in California has historically been higher than it is seemingly worth, but cutting alfalfa out of the dairy ration to reduce feed expenses wouldn’t be worth the resulting drop in production. “Intake would almost certainly decrease to some degree, and if the intake’s going to go down, then the production will go down as well,” Robinson says.
Silage solution
Silage was not introduced to dairy rations in California until the 1980s. Today, it makes up 10 to 15 percent of the dry matter in rations. Some producers have tried to lower feed costs by reducing the amount of alfalfa hay in the ration and replacing it with corn silage, reasoning the change in diet would not negatively affect the energy intake or output of the cow.
“The reason someone would put in more corn silage is primarily driven from an agronomic standpoint,” says Wisconsin-based nutritionist Bill Matzke. “In Wisconsin, my alfalfa fields would generally yield 4 to 5 tons of dry matter per acre, versus when I can grow an average yield of 6 to 7 tons of dry matter per acre with corn, so you can see the advantage in terms of yield to corn silage.”
Matzke also says milk production and nutrition levels should remain relatively the same with the increase of corn silage in the diet, making it a sound economical choice from all sides.
Silage has a valuable role in the dairy ration as well. Matzke says the dairy community has learned a lot about silage since its emergence as a key ingredient in dairy rations. “If you go back, we feed a lot more corn silage than we did 20 years ago,” he says.
Matzke says it is much easier to pinpoint exactly what benefits farmers get from feeding silage, enabling them to feed it out more effectively. “We have a lot better tools to analyze in terms of what is the true quality of corn silage,” he says.
“We have an estimate of rate of fiber digestibility, and we have our ability to process kernels, and in the last 10 years we’ve made substantial improvements in our ability to pick correct varieties that have traits of far better neutral detergent fiber digestibility.”
Like Robinson, Matzke sees no way to completely eliminate alfalfa hay from feed costs. Matzke says alfalfa hay provides a little variety in the generally corn-heavy diet. “We feed a lot of corn products.
We feed corn grain, we feed corn silage, and we feed corn byproducts, whether it be distillers or corn gluten feed,” he says. “Alfalfa brings in a little different amino acid profile, and besides just bringing in crude protein into the diet, it also brings some particle length for effective fiber to the TMR.”
Alfalfa hay brings more value to the dairy ration than simply giving variety to the mainly corn-based mixture. It has even more value to the digestion process than consulting nutritionists take into account.
Hidden benefits
Robinson says there are more benefits to using alfalfa in a hay ration than what nutritionists are currently able to analyze. He says, “There are things about alfalfa hay that we don’t seem to fully understand nutritionally, and some of those could be not just the protein level but the types of proteins and how they’re metabolized in the rumen.”
Robinson says since alfalfa hay breaks down really well when it’s put into a TMR, it gets mixed through the entire ration so the animals eat it with everything else. He says the short alfalfa fibers are important because they create an environment in the rumen where there is more eructation and ruminative chewing.
“That’s really important because when they chew, they’re salivating and getting a lot of buffer being produced, and the buffer ends up being swallowed continuously into the rumen and can buffer rumination,” Robinson says.
Robinson says alfalfa hay has a high inherent buffering capacity, which is never measured by nutritionists. “We don’t formulate the buffering capacity of the feeds,” he says. “From that perspective, it has a very high value.”
Alfalfa hay also has a relatively low fiber content for forage. Robinson says structural fiber levels, or neutral detergent fiber levels, are 60 to 65, even 70 percent for typical grass forages, but alfalfa hay is closer to the range of the high 30s. “What that means is: There’s a lot of material in there we don’t fully analyze.”
Robinson says nutritionists usually analyze for the protein, fat, structural fiber and the minerals, and leave the rest out. “We just call that non-structural carbohydrates or non-fiber carbohydrates, which is a fancy term for everything we didn’t include in the analysis,” he says. “That material has a very high percentage in alfalfa hay, so alfalfa hay has a relatively high energy value for a forage.”
Research in the future
Robinson says not a lot has changed in how dairy producers are better able to utilize their alfalfa. “We’re still playing around with the basic analytical package that we’ve been using for 25 years,” he says. “It’s variations on a theme. There’s nothing really new or different we’re doing now; it’s small adjustments.”
Robinson says the transition from the crude fiber system to the detergent fiber system in the 1970s was the last big breakthrough he can remember.
“Everything changed in ration formulation and, arguably, the ability to create rations that were better balanced nutritionally increased dramatically,” he says. “After that, it’s been relatively small increments. That’s probably going to continue into the far future, but I don’t see anything else out there that’s going to be a game-changer.”
Robinson says while he doesn’t see a lot of ground-breaking changes in ways producers can better understand how alfalfa works in a dairy ration happening in the near future, the small adjustments and improvements will keep the dairy industry moving forward in innovation. Thus, for farmers who do not grow their own hay, alfalfa will continue to be a necessary expense. 
PHOTO: Peter Robinson, dairy nutrition extension specialist with the University of California – Davis, says dairy consultants have tried for years to find ways to take alfalfa hay out of the dairy ration without success. Photo by Mike Dixon.
-
Carrie Veselka
- Associate Editor
- Progressive Dairyman
- Email Carrie Veselka
