Ohio Farmer

Researchers are looking for genetic traits that affect how efficiently cattle use feed.

Gail C. Keck, freelance writer

May 3, 2019

7 Slides

At its beginning, ST Genetics specialized in sorting cattle semen by gender, but the company has gone far beyond that in its research efforts.

For instance, researchers at the company’s Ohio dairy farm are currently narrowing down the genetic traits that affect how efficiently cattle use the feed they eat. The farm also uses robots to milk the cows and cellphone apps for data entry, and it recycles manure for bedding using a dryer powered by a manure-fueled gasifier.

“We’re a normal operating dairy farm — in an unusual way,” says Paul Detwiler, general manager of the ST Genetics Ohio Heifer Center near South Charleston, Ohio.

The heifers raised at the Ohio Heifer Center and the cows milked there are being used to develop better dairy genetics. In the past, most feed efficiency research focused on what to feed cattle to get the best performance.

“It’s always been about more inputs, more inputs, more inputs,” explains Detwiler.

However, ST Genetics’ EcoFeed research is aimed at identifying cattle that have the desired rate of gain or milk production with the lowest feed intake. The company has found that feed conversion is not correlated with any other genetic trait. And breeding for a single trait without considering others can lead to improvement in the selected trait, while other traits show genetic declines. That makes it difficult to achieve genetic improvements in feed conversion, but ST Genetics is seeing promising progress, Detwiler says.

The potential benefit of genetically improving cattle feed conversion really adds up, explains Gregg BeVier, chief operating officer for ST Genetics. Consider a heifer that requires an average of 10 pounds less feed each day than an average heifer. In the two years it takes for her to grow to maturity, that adds up to more than 7,000 pounds of feed, or about 3.5 tons. If the feed cost averages $180 per ton, it would cost $630 less to raise that heifer.

Improving feed conversion for cows in a milking herd would have similar advantages, BeVier points out. “Feed represents about 60% of the cost of production.”

Efficiency is key

To identify animals with superior feed conversion, the researchers are monitoring cows through a 160-day test period, measuring feed intake and milk production. They’re looking for the cows that convert feed to milk most efficiently.

“We want those animals that are going to produce on less feed,” Detwiler says.

Heifers are monitored through a 90-day test period, measuring feed intake and growth. The researchers aren’t looking for the fastest rate of gain, but rather the most efficient rate of gain, Detwiler explains. For example, consider two heifers that are full sisters with all genetic indexes almost identical. Both grow at nearly the same rate, but one averages 7 pounds less feed intake per day. The one with the lower feed intake shows better feed conversion, so she would advance to the farm’s breeding herd as an embryo donor to multiply her genetics. Meanwhile, the other heifer would most likely end up as an embryo recipient to carry a calf from a donor.

Farm development

ST Genetics is a global company with labs and research facilities around the world. The company bought the Ohio research farm in 2010 and initially used the facilities to assemble and breed groups of dairy heifers before exporting them. Most were headed for Turkey or Russia, and the company exported about 30,000 heifers over a four-year period. However, as political and economic situations changed, the market for bred heifers evaporated, Detwiler explains. The farm then began focusing on research efforts and producing genetically superior embryos.

The farm had previously been a beef cattle feedlot, with eight finishing barns each 1,440 feet long. The facilities have been repaired and upgraded to house the dairy cows, heifers and calves in the research herd.

About 50 to 60 heifers are born at the farm each week. They start out in a crib barn, where they are isolated with no nose-to-nose contact to help minimize health problems. At 3 weeks old, they are moved into group pens, where they can socialize. There, they are fed with a robotic system that allows them to eat as much as they want, whenever they want. They’re gradually shifted into larger groups; and at 70 days, they start on the monitored feeding trial.

Efficient bedding

The farm’s milking herd is housed in solid-bedded pack barns. That’s the second-best environment for cows — next to open pasture, says Detwiler. The scale of the farm makes pasture impractical; but in the bedded pack barns, cows are free to mingle, eat and rest in open pens on dry bedding. Studies of cow behavior show cows will sleep more in bedded pack housing than in freestalls because they’re more comfortable, says Detwiler. “She feels good, and she’s healthy.”

The bedding system does require more bedding than a typical freestall setup, Detwiler notes. “It’s a big commitment to keep them clean and dry.”

The sawdust and straw used for bedding on the farm is dried and recycled after it becomes dirtied with manure. To provide heat for the 32-foot drum dryer used for the manure, the farm uses a gasifier. The gasifier needs a little natural gas to start, but it is mainly fueled with manure. Gasification releases energy from the manure fuel, using heat and a limited amount of oxygen that does not allow combustion.

The manure drying system takes manure moisture from about 55% to 25%, and that dried manure can be reused as bedding. On a sunny, dry day, the system can dry 20 tons of manure per hour. On average, Detwiler explains, they make about 3.5 semiloads of recycled manure bedding per day. The manure system has been in use for five years and cost $2.5 million. It has more than paid for itself, Detwiler points out, because recycling bedding saves the farm about $750,000 each year in bedding purchases.

The gasifier also produces biochar as a byproduct. Compared to biochar produced from wood, it has lower carbon content and more micronutrients, Detwiler says. It could be used as a soil amendment, but there are higher-value markets for the biochar. For instance, AbTech Industries, an Arizona-based water treatment company, is testing the biochar as a binder for phosphorus. The biochar is currently being used on a project to keep contaminated runoff from an abandoned New Jersey industrial site out of the Hackensack River.

Phone apps and robots

To help employees record information on research projects and farm operations, the farm uses an Android-based data entry system. The system lets employees enter data using their cellphones as they go about their work, Detwiler points out. Of the 70 farm employees, about 50 are under 30 years old, so they’re used to managing information with their phones, he says. “They’re going to be on their phones anyway.”

The farm’s most recent management change came with the installation of 16 Lely robotic milkers earlier this year. With the robotic milkers, the company is converting to a management system that allows cows to follow their own schedules: eating, resting and going in to be milked whenever they want. “It’s designed for the cow,” Detwiler says. “She’s in charge of everything.”

Cows even get to choose whether to be milked from the left side or the right. Half the robotic milkers approach cows from one side and half from the other, because each cow has her own preference, he explains. The robotic milkers are arranged in groups of four, and each group will handle up to 200 cows. The computerized milking system tracks milk production as well as multiple health and heat indicators.

Cow-centric milking

Using the robotic milkers is not necessarily the most convenient for people when it comes to breeding, hoof trimming or other management tasks, Detwiler explains. “But it’s the most efficient for the cows.”

The staff establishes how many times a day each cow can be milked, based on her stage of lactation. For instance, for a cow producing 100 pounds a day, they would set the system to give the cow permission for milking four times in 24 hours. The number of milking permissions is tapered off for cows ending a lactation.

While the cows are being milked, they each get a measured amount of pelleted feed. The feed has an apple pie scent and flavoring to attract cows to the milking stalls, Detwiler explains. “We want cows to want to come to the robots.”

Cows can enter the milking stalls as often as they want, but they only get fed and milked when the computerized system indicates they have permission. Some cows go in and out repeatedly because they want the feed, says Detwiler.

The record-holder is a cow named Stacy, who entered 28 times in a 24-hour period, but only had permission for four milkings.

Keck writes from Raymond, Ohio.

 

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