Adding hybrid rye to dairy rations could reduce costs

FREEPORT, Ill. — Changing feeds in dairy cow transition diets can help reduce costs.

“Most of you are feeding some straw to your dry cows,” said Phil Cardoso, associate professor at the University of Illinois. “If you allow it, cows will eat more than they need, so we add wheat straw to limit the intake so they eat just what they need.”

The control energy diet typically has 25% to 35% straw on a dry matter basis to limit the intake of the cow, said Cardoso during a presentation at the 2006 Illinois Dairy Summit, hosted by the Illinois Milk Producers Association and U of I Extension.

Researchers at the U of I planted a hybrid rye, KWS Progas, to evaluate the impact of replacing wheat straw with the hybrid rye in a transition ration.

“We seeded the rye in October on about 10 acres and we harvested it at the boot and milky stage,” Cardoso said.

For the boot stage the hybrid rye was harvested in May and it produced 8.46 tons per acre.

“We made bales because we were afraid if we put it in a silo we would not remove enough of the face to get fresh material all the time,” Cardoso said.

In June, the hybrid rye was harvested in the milky stage and it produced 13.6 tons per acre. No inoculants were put on the bales.

“Four months later we collected samples from the bales and sent them for analysis to evaluate the fermentation,” Cardoso said.

“When ensiling anything, we want the acid to go up as soon as possible to prevent any bad bacteria and other contaminants to grow,” he said.

“We formulated the diets, so they were very similar,” the associate professor said. “You need a nutritionist, but there is a potential for a cheaper diet with hybrid rye because the straw has 7% crude protein and the rye is about 13% to 14% crude protein.”

Since the researchers were feeding from the bales of hybrid rye, they chopped the bale and then mixed the diet.

“Every week in our trials we use the Penn State Particle Separator and about half of the ration was in the top sieve,” Cardoso said.

“Our cows only eat from one gate during the dry period, so that means competition does not exist,” he said. “So, if you are overcrowding your dry cows, I would think about this being an issue because cows will eat different diets because of the sorting.”

Total Mixed Ration

Sorting is something the researchers need to work on, Cardoso said.

“The appearance of your TMR matters,” he said. “If you have larger particles on top, make sure the cows are not overcrowded and you give them time to eat that material.”

The researchers found no difference in intake between the rations with wheat straw and the hybrid rye.

“There was also no difference in energy balance, body condition score, body weight or urine pH,” Cardoso said.

“We also did a colostrum analysis and did not see any difference,” he said. “The intake and milk yield postpartum were the same, but we still have to evaluate the milk components.”

“It seems like we can have a cheaper diet by replacing the wheat straw with the hybrid diet,” the associate professor said. “Since the rye has higher crude protein, you can save some money on the amount of soybean meal in the ration.”