Dry conditions in Kansas and other areas of the Midwest have caused many cow/calf producers to look at more cost-effective ways to adequately feed their herd. One of the hot topics in the beef sector today, especially in dealing with drought, is that more producers are considering confined feeding for cows using low-quality forages with protein by-products.
The process of using anhydrous ammonia to treat and enhance low-quality forages, such as wheat straw and corn stalks, is not a new concept to help producers save on feed costs, said Justin Waggoner, beef systems specialist for K-State Research and Extension. Ammoniation increases the digestibility and dry matter intake of low-quality forages.
Waggoner, who works at K-State’s Southwest Area Extension Office in Garden City, recently looked at using two different rates of anhydrous ammonia application on wheat straw that is fed with wet distiller’s grain to pregnant beef cows. He said the traditional rate of anhydrous ammonia application recommended for producers has been a 3 percent application (60 lbs/ton) on a dry matter basis. His latest research compares the 3 percent application to a 1.5 percent application (30 lbs/ton).
“Our primary interest in doing so is due to the current cost of anhydrous ammonia,” Waggoner said. “When the research was done to establish that rate of 3 percent, anhydrous ammonia cost about $200 a ton. Today, we’re looking at anhydrous ammonia prices at $700-$800 a ton, so there’s an opportunity for some cost savings by reducing the application rate.”
A closer look at the research
Although Waggoner and his colleague John Jaeger, a K-State beef cattle scientist at the Western Kansas Agricultural Research Center in Hays, have studied forage quality in the past, they hadn’t had the opportunity to do an actual cow feeding study until now. A total of 132 second-trimester, spring-calving, Angus-cross cows were examined. A majority of the cows were 4-5 years old.
Former research evaluating ammoniated wheat straw as a component of a beef cow diet didn’t include wet distiller’s grain, Waggoner said. This provided an opportunity to study ammoniated forage in a more modern diet with wet distiller’s grain. The cows were limit fed at 1.9 percent of their initial bodyweight.
“On a dry matter basis, the diets were about 65 percent wheat straw, 20 percent wet distiller’s grains and rolled sorghum at 15 percent,” he said.