It seems you can’t catch a break these days. The cost of major inputs – feed, fuel, fertilizer – continues to scoff at your profits.
When it comes to feed cost, there are some strategies, like feeding a high-forage diet, that can help you wipe that smirk off the face of high concentrate prices.
High-forage diets represent a prime opportunity – a silver lining, if you will – during tough economic times. Some herds have already found this silver lining and made it work.
Surveys of high-producing herds in Wisconsin over a six-year period found that forages made up 50 to 60 percent of ration dry matter. What’s more, these forages contributed substantial percentages of certain nutrients to the diet. And it was not just fiber, but also protein, starch and energy – what you would expect concentrates to provide.
Now is a prime time to be more aggressive with the forage portion of your lactating-cow rations. Here are some strategies to help you reach 50 to 60, even 70 percent forage dry matter, without hampering feed intake and milk yield.
Choose low-fiber forages
Forages vary significantly in their neutral detergent fiber (NDF) concentration (Please see the table at right.) Forages with a high NDF content are more filling, which can limit feed intake, says Mike Allen, dairy nutritionist with Michigan State University.
To offset this problem, select forages with a lower NDF concentration when you’re feeding a high-forage diet.
“So, for instance, if we balance for 21 percent forage NDF in the ration, using a forage with 35 percent NDF would give us a ration with 60 percent forage,” Allen says. “But if we used a forage with 45 percent NDF, only 10 units higher, then our ration drops to 47 percent forage.”
Keep in mind that the maximum amount of forage NDF that you can add to a ration will vary based on several factors.
“It varies with milk yield, but it also varies with the digestibility of forage NDF and with forage type,” Allen says,
“Although perennial grasses generally have greater fiber digestibility than legumes and corn silage, the fiber is more filling because it is more resistant to particle size breakdown and passage from the rumen.”
That, combined with higher fiber concentrations, limits the forage concentration of rations that include grass compared to rations containing legumes and corn silage.
You can feed a higher forage diet without losing milk production as long as the fiber in the forages is highly digestible, Allen says.
High fiber digestibility is a key attribute of brown midrib (BMR) corn silage hybrids, which make them an excellent fit in high-forage diets.
BMR corn silage is the predominant forage in the rations at Koepke Farms Inc., Oconomowoc, Wis. John Koepke, who operates the farm in partnership with his dad Jim and his uncles Alan and David, has been feeding BMR corn silage for about eight years now.
When you’re feeding BMR silage, your forage needs will increase, Koepke says, so make sure that you budget your forage supply accordingly.
“With my diet, which is approximately 50 percent BMR corn silage and 50 percent legume silage, that typically means 2 to 4 pounds more corn silage per cow per day (on a dry matter basis),” Koepke says. “I would say in most years it’s on the upper end of that. It might even get above 4 to 5 pounds of dry matter.”
Koepke also has learned to make diet changes gradually. The key, he says, is to slowly introduce more forage into the diet.
“I started by bringing in the BMR corn silage gradually and then increasing the amount of pounds fed and decreasing the amount of grain fed,” he says.
All cows benefit
Forages with high NDF digestibility benefit all cows, allowing you to feed higher forage rations to cows and maintain, or even increase, milk yield.
However, cows respond differently to changes in forage fiber digestibility and concentration. During a webinar hosted by Dairy Herd Management last month, Allen shared research showing that the benefits of a lower forage NDF diet increased with level of milk yield.
“So as milk yield of the cows increased, the response was greater,” he says. “Only cows over 80 pounds of milk responded positively in fat-corrected milk yield to the lower (16 percent) forage NDF diet.”
To access the webinar hosted by Dairy Herd Management, go to dairyherd.com Once there, point your browser at the “News” tab, scroll down to “Events” and click on “Webinars.”