Switching from hay to a combination of straw and grain prior to calving can save about $350 a head during the winter, says provincial beef and forage specialist Barry Yaremcio.
“The question then becomes: Is it cheaper to feed oats or barley to the cows?”
The answer to that question depends on the price and nutrient content of each grain.
“On average, barley contains seven to 10 per cent more protein and seven to 10 per cent more energy on a pound-for-pound basis compared to oats,” said Yaremcio. “So if there is six pounds of barley in the ration, it would be necessary to feed 6.6 pounds of oats to get the same amount of nutrients into the animal.”
That means oats need to be $1.50 per bushel cheaper than barley to be cost effective.
But that’s not the whole equation.
“If feeding whole grains to calves under 700 pounds, there’s no need to process the grain,” he said. “The calves will do a good job of chewing and breaking the kernels so they are digested. For animals over 700 pounds (including cows), the animals tend to ‘gulp’ their food and don’t chew as much. Whole oats to larger animals results in a five to seven per cent reduction in digestive efficiency. Barley on the other hand has a 10 to 15 per cent reduction in digestive efficiency when fed whole.”
So the next step is to factor in the processing cost.
“If it is costing more than 15 per cent of the price for barley or seven per cent of the price of oats to process the grain, it may be beneficial to feed extra grain and be money ahead in the long run, said Yaremcio.
And if you change from oats to barley in a ration, do it gradually, he said.
“Start with 25 per cent barley in the mix for three to four days, and then increase the barley by 25 per cent every three to four days. If all goes well, in 16 days the animals can be on 100 per cent barley.”
Changing to feed wheat has different limitations.
“Wheat must be cracked into two pieces (but no finer than this) when fed to larger cattle. If it is fed whole, digestive efficiency is reduced by 25 per cent.”
Wheat also ups the risk of bloat or acidosis as it is digested faster.
“Maximum feeding limits for wheat is three pounds per head per day for calves under 700 pounds and six pounds a day for mature cows,” said Yaremcio. “If switching to wheat, a gradual introduction into the ration is necessary. It’s advisable to include an ionophore into the ration when feeding wheat.”
When changing from one grain to another, there are two things to watch for:
- Feed refusal. If feed consumption declines after a change, the rumen may not be functioning properly.
- Consistency of the manure. Loose and watery manure is another indicator there are digestive problems.
“If either of these two problems occur, reduce the total amount of grain fed or go back to the previous mix of grain until the problems dissipate,” said Yaremcio.