A prescription for profitability: Amino acids can boost milk checks

FREEPORT, Ill. — A total mixed ration is a prescription for dairy herd profitability.

“You want your cows to give a lot of milk, be healthy and rebreed. Those are the signals for profitability,” said Phil Cardoso, University of Illinois Department of Animal Sciences associate professor.

“A cow seven days in milk needs a lot of energy and usually she can not get all the energy and that’s when she goes to negative energy balance,” Cardoso said during the Illinois Dairy Summit hosted by the Illinois Milk Producers Association and U of I Extension.

“Metabolizable protein is the same story, so she has a negative protein balance, as well, which usually lasts three to four weeks, and that is a big deal,” he said.

Research shows that a ration for dairy cows with 13% crude protein or 25% crude protein results in the same milk production, Cardoso said.

“That tells us the crude protein is not a good determinant on how the cows are performing,” he said. “Metabolizable protein is what cows use and should be our focus and proteins are made of amino acids.”

The two limiting amino acids for milk production are methionine and lysine, Cardoso said.

“We need to formulate diets with the focus of getting the cow these amino acids,” he said.

“Check your cattle diets. They should have 1.200 grams of metabolizable protein per day during the pre-fresh period,” he said.

“Talk to your nutritionist because you need to know the profile of that protein so the amount of methionine and lysine are sufficient,” he said. “It should be a 2.8-to-1 ration with 2.6% of the protein made of methionine and 7% made of lysine.”

The challenge for researchers, Cardoso said, is to determine where energy is coming from in cow’s diets.

“I can have a diet with high fat and low starch or high starch and low fat with the same amount of energy,” he said. “So, we need to figure out which component of energy will work better for your cows.”

Cardoso talked about a research project where cows were fed rumen-protected lysine before and after calving.

“Cows that were fed lysine preserved a little more body condition score,” he said.

“If you feed lysine before calving there was a tendency for the cows after calving to eat more,” he said.

Increasing the amount of protein cows produce in their milk can impact the profitability of a dairy herd. A herd of 100 cows producing 90 pounds of milk per cow per day totals 9,000 pounds of milk production per day.

“With 3.3% protein, if you increase that by 0.2 and you’re getting paid $3.65 for protein, that’s an increase of $65 per day or $1,900 per month,” Cardoso said.

“With the cost to feed amino acids at 20 to 30 cents, that equals $600,” he said. “So, it costs you $600 to get almost $2,000, which is a no-brainer since it is almost a 4 to 1 ratio of return.”

At the U of I, a research project that included 32 cows split into two groups looked at the impact of feeding methionine during heat stress.

“For the heat stress we used electric heat blankets,” Cardoso said. “We evaluated the cows for nine days for the baseline and the next nine days they had heat stress.”

During the heat stress period, the cows had higher vaginal and rectal temperatures and the respiration rate was pretty high, as well as the heart rate.

“The intake from the two groups was pretty close, but the one thing that surprised us was the heat stress cows produced more milk,” Cardoso said.

“The cows dropped less milk protein with heat stress when they were fed the rumen-protected methionine, and the same thing happened with casein,” he said.