Brown midrib (BMR) corn is gaining attention from dairy farmers. And no wonder.

Evidence is mounting that BMR corn, known for its enhanced silage digestibility, boosts milk production.

"Unofficially, we are hearing reports from the field of cows producing 3-8 lbs more milk per day," says Mike Hutjens, a University of Illinois dairy specialist who's testing the corn.

In earlier Michigan State University research, cows consumed 5 lbs more of a total-mixed ration with BMR silage and produced 5.5 lbs more milk per day.

Lower in lignin than conventional corn silage, BMR silage digests and passes through the rumen faster, explains Michigan State dairy scientist Mike Allen. The result: greater feed intake, higher milk production and/or body condition, says Allen.

But BMR seed isn't cheap. It costs about three times as much as conventional corn and produces less tonnage, says Hutjens.

"It takes about 1 1/2 lbs more milk per cow per day to pay for the added seed cost and offset the lower tonnage," he states.

"As a dairy producer, I'd experiment with brown midrib on a third to a quarter of my silage acres this year and run it through my cows to see how it performs."

He and his colleagues are conducting BMR research on seven farms. Full results of the first research phase - evaluation of BMR yield and forage composition - will be available later this year. But Hutjens offers his initial observations.

"We had expected a 5-7% tonnage reduction on brown midrib, compared to conventional hybrids. But our cooperating producers were running 16-17% less tonnage," he says. "However, we were matching it against the very best grain and silage hybrids available."

BMR has about half as much lignin as conventional corn silage and is 6-8 percentage units higher in total-plant digestibility, says Hutjens.

He advises dairymen to make adjustments when feeding BMR. "Reduce the grain and increase the fiber because BMR is a high-energy feed," he notes.

Nutritionists for Cargill Hybrid Seeds recommend altering dairy rations to 55% forage and 45% grain before starting to feed BMR silage.

Cargill has four BMR hybrids, ranging from 100- to 118-day maturities, available this spring.

"I would ask Cargill for the very best hybrid for my region, and would plant it on my least stressful fields," advises Hutjens. "That will minimize tonnage reduction."