Dairy producers across the country have complained about low milk fat this year, though nutritionists have been hard-pressed to explain it.
Some blame bare-bones rations that have all additives pulled out to save money; others say the inclusion of high-fat, highly variable byproduct feeds are to blame. In any event, researchers at Clemson University, Washington State University and Arm & Hammer Animal Nutrition may be on the path to a solution.
Studies have long shown that the inclusion of Arm & Hammer’s DCAD Plus feed grade potassium carbonate will improve milk fat in control diets that produce low levels of fat. But recent work at Washington State also showed a response in fat percentage, fat-corrected milk and a 3% bump in feed efficiency when DCAD Plus was added to control diets with 4% butterfat.
To understand why, researchers at Clemson conducted several artificial rumen experiments. Their work suggests that DCAD Plus, which provides additional potassium, allows rumen bugs to hydrogenate fatty acids without depressing milk fat.
“We know a lot of the factors that can cause bad things to happen in the rumen to depress milk fat. This is the first time we have something that positively affects it,” says Elliot Block, senior manager of technology for Arm & Hammer.
“I don’t think we have widespread deficiency of potas-sium in dairy diets,” he says. “But we could have a problem of it being limited. Cows really struggle to maintain a balance early in lactation, when there’s high milk production and a huge demand for potassium.”
More lab work and animal studies need to be done. But as word of the research gets out, some nutritionists are adding as much as a half pound of DCAD Plus per cow per day in herds with milk-fat depression.
Because that inclusion rate can cost 30¢ to 35¢ per cow per day, they will need a 0.35% unit increase in butterfat, or 2 lb. more milk, to break even. But if they get a positive response, they can ratchet back the inclusion rate to where they can maintain milk-fat levels.
Source: Arm & Hammer Animal Nutrition