Raising dairy replacement heifers in managed grazing systems provides economic savings and ecological improvements, along with improved animal performance as they enter the milking herd, according to Jason Cavadini, University of Wisconsin Extension grazing outreach specialist.

While many dairy farms have implemented heifer grazing successfully, Cavadini said many dairy farms have not. 

“In 2015, it cost $2.77 per head per day to raise a dairy heifer,” Cavadini noted during a recent Professional Dairy Producers webinar. “In 2023, it cost $3.15 per head per day to raise a dairy heifer. Fifty percent of that cost is for feed.”

Cavadini believes grazing dairy heifers is one solution to help reduce the cost of raising them. But he said that while some farmers graze heifers, many farmers have gravitated away from the practice.

“While dairy has focused heavily on efficiencies over the years, we do have room for improvement in some areas,” he said. “Grazing could potentially be a solution for achieving efficiency and lowering the cost of raising heifers to less than $3.15 per head per day.”

Cavidini and fellow researchers asked dairy farmers what is stopping them from implementing grazing as a soil- and nutrient-saving solution on their farms.

Related:Grazing: An old idea that’s new again

“And we asked people who they work closely with and take advice from — ag lenders and dairy nutritionists — what’s stopping you from supporting grazing as a feeding and performance solution?” Cavidini said.

The researchers found that all parties are open to grazing heifers. No one questions the economics of grazing. Those surveyed cited how they have seen grazing managed very successfully and very poorly, with a range of results in between. They want to know how they can dial in and be successful at grazing.

Principles of managed grazing

Cavadini said it all comes down to teaching the three principles of managed grazing:

“Allowing pastures to rest for 30 days and keeping the stocking rate at the right level is important too,” he said.

Cavadini said there are eight common goals of managed grazing:

“You have to be able to manage successfully enough to maximize the grazing season,” he said.

Residual is key

Cavadini recommends farmers leave 4 inches or more of residual growth on pastures in October.

“We did a study and had farmers leaving 6 inches of residual grass on some pastures and 2 inches on others,” he said. “We compared both pastures for the entirety of the next season and found that the pastures that had been grazed down to 2 inches yielded 25% less, which decreased the stocking rate by just as much.”

Cavadini said when 4 or more inches of residual growth are left on pastures, photosynthesis can continue.

“When you leave less, you actually stop growth for up to 17 days because any energy that’s collected from the sun is going to restoring root resources,” he explained. “Until that is done, aboveground growth won’t happen. That’s why it is very important to maintain that residual.”