Due to the dry summer conditions and lack of hay supply many cattle producers implementing more corn silage into their feed rations than they have in the past. This has led to many questions on how to properly implement corn silage into the feed ration, says Julie Walker, SDSU Extension Beef Specialist.
"I have received numerous calls from cattle producers asking how much corn silage they can use and what is the minimum amount of hay that a cow needs," Walker said.
To help answer these questions, Walker points to a research project she completed at Purdue University which evaluated limit feeding corn silage to meet the nutrient requirements of the beef cow.
"We found that limit feeding corn silage can be a good option for overwintering beef cows. As you know corn silage typically has higher energy than the typical beef quality hay, so the cow's energy requirements will be met with less total dry matter intake of silage compared to a hay diet," she said.
However, Walker says producers need to be aware of the fact that protein supplementation may be needed - depending on the protein content of the silage.
"The specific amount can only be determined by testing the feedstuffs and then balancing a ration," she said. "Also, with the drought conditions this summer, it is important to test the corn silage for nitrates."
Walker's research also looked at replacing part of the hay in the diet with corn.
The diets were 0.5, 1.0, or 2.0 percent of the cow's body weight as hay plus corn to meet the cow's nutrient requirements.
"We found that the 0.5 percent of the cow's body weight of hay plus corn had the same performance as the 2.0 percent the cow's body weight of hay treatment," she said. "At calving time the cows were in similar body condition and no calving problems were found."
She does point out that although the 0.5 percent and 1.0 percent hay treatments met the cows' nutrient requirements, they did not completely satisfy their appetites.
"The cows were hungry during the adaptation period, and we learned the value of good fences," Walker said.
All of these treatments were balanced for energy and protein to ensure the desired performance. During the research project, Walker says they made sure that all of the cows had adequate bunk space
The rations were fed as a total mixed ration using a mixer wagon. Because some producers may not have a mixer wagon, Walker says limiting the hay supply with this method may be difficult.
"Remember the key to success with this program of feeding in 1) testing your feedstuffs, 2) balancing a ration, and 3) ensuring adequate bunk space," she said. "It's also important that producers ensure their cows are on a good mineral and vitamin program. With limiting feeding, cows might over consume the recommended consumption rates, so producers can use white salt to limit consumption."