While per-cow milk output in Wisconsin is below 22,000 pounds a year, the number keeps increasing every year and some top herds now average more than 40,000 pounds per cow. Individual cows have topped 70,000. Even the world record-holding Jersey cow has more than 40,000 pounds of milk in a single lactation. Just how high can milk production go?
The sky may be the limit, according to Kent Weigel, chairman of the Dairy Science Department at University of Wisconsin-Madison and professor of dairy breeding and genetics.
Mark Stephenson, director of the UW Center for Dairy Profitability, calls it an amazing trend.
"It's close to 300 pounds per year that we're increasing milk production. It's tremendous."
"They keep going a lot further than people think," adds Weigel. "We can certainly improve genetic progress" with technology like embryo transfer and sexed semen. The latter, he says, "has a very large impact" by producing more heifers out of top animals in a herd. The practice is doing away with the long-held dairyman's complaint of never having enough heifers.
Although "an animal can't produce an infinite amount" of milk, any slowing of increasing production is not apparent right now, Stephenson says. "You know there's room for improvement. It depends a little on prices as to how hard farmers are going to push their cows. Not only milk prices, also feed prices."
He's seen no evidence that cows are "burning out" by being pushed to ever-higher outputs. "It's just not the way it is. High-yielding cows are like high-yielding athletes."
Dairy farmer Tom Kestell of Waldo says he did "nothing special" with his world record cow, a registered Holstein, when she produced 72,190 pounds of milk in 365 days as a 4-year-old.
"It was mostly breeding," he feels, "but all things fell into place... I think genetics plays the largest role with high milk production" in combination with the environment, management and feeding. "The genetic improvement is in the crops too. Quality and digestibility are up."
Kestell, an international marketer of dairy embryos, puts his herd average at over 42,000 pounds of milk with a 4% butterfat test. He has a 3-year-old that recently finished a 67,800-pound lactation and "quite a few more over 60,000. I spend a lot of time" with embryo transfer "and that distracts. I can get to 43,000-44,000 without that."
His world record cow, now over 10, has been retired from the milking herd to produce embryos, passing on her high production genes to her offspring.
So, can dairy farmers continue to look for ever-higher milk production? "Yeah, I think so," says Weigel. It will come from both improved genetics and improved management, according to Stephenson. Monthly production reports, he maintains, "are part of our system of intensive dairying. It allows us to push cows and cows have responded well."
But, Weigel cautions, at what cost, suggesting that purely increasing milk output isn't always the answer to dairy profits.
"The highest herds in the state are over 40,000 pounds per cow. Is that the right matrix? I'm not sure. As you push higher and higher, rations become more expensive and need more fine tuning than ever; consultants enter the picture... On the veterinary side you have to be careful with injuries and health problems, costs might be higher."
And there are constraints, notes Stephenson. In the warmer southern states, he notes, cows have more body heat to dissipate, "making it difficult to achieve the high potential of our genetics. A lot has to do with the environment. All the low-yield states are in the South and Southeast" where some states average only about 13,000 pounds.
The ultimate question, Weigel says, "Is it profitable? What's the ultimate goal? Milk for profit. Rolling herd average is not the same as profit."
"It's not just milk per cow," Stephenson agrees, "we're more interested in farm profitability. Highest production is not the most important thing you can do, although it is a good strategy for farmers. We also think of not only how much milk but what components. We're interested in how much protein, how much butterfat. If you're low in component values, that may not always be the best strategy either."
Reaching those top levels of production, he says, combines breeding and management, and "better management really is doing everything right - cow comfort, protecting feet and legs, best quality feed. It's a complex business."
"If you're going to have high producing cows it starts and ends with genetics," says Kestell. "Genetics in the cow, in feed, maybe even the farmer... Working with consultants helps but you have to have the pieces fall into place." While he sees many more herds in the state topping 40,000 pounds of milk per cow in the next 10 years, he also advises, "Don't try to force the cow into something that isn't natural. As a dairyman, you've got to know what that is."
According to Weigel, a federally-funded project measuring feed efficiency is under way among thousands of cows in the U.S. and Canada.
"We are measuring feed intake to compare energy input in the ration with energy output in milk yield, milk composition, maintenance of body weight, and gain or loss in body weight," he says. "Some cows do better than others."
The studies are showing higher milk yield will increase the ratio of feed used for production to feed used for maintaining body weight, but at an ever-slower rate.
"There are many cows that are consuming feed to produce milk at 4, 5, or 6 times their maintenance cost," he says. "Efficiency increases at a slower rate, though, and if we are pushing too much feed into the cow at one time it might reduce her ability to digest the ration."
Dairy Moos, a dairy farmer-authored blog, shows in a graphic illustration, but listing no source, that it currently takes 63 pounds of feed to produce 100 pounds of milk, compared with 110 pounds in 1980.
"I do not breed cows to eat more," says Kestell, who is aware of the study. "I breed cows to have more efficiency with what they eat. The dairy industry has kind of ignored feed efficiency but it will be more and more important."
The study of the issue, along with others under way in the Netherlands and Australia, recognizes that. Weigel points out that the first preliminary genomic predictions of AI bulls for residual feed intake (a measure of feed efficiency) will be released by spring or summer of 2016.
He says, "Initially we'll share these with USDA and the Council on Dairy Cattle Breeding in order to determine if and how to move forward with routine predictions for Holstein bulls and cows. A big challenge is that this is a new trait that is difficult and expensive to measure, so the genomic reference population will be small, and the reliabilities for RFI might be only 25% or 30% compared with 60% or 70% for genomic predictions for other traits."
Buchholz lives in Fond du Lac.