Search for superior dairy hybrid regains attention with producers

SALEM, Ohio – Fifty years ago in Pennsylvania, dairymen were concerned that the existence of 8,000 dairy-beef crosses were going to ruin the Pennsylvania Dairy Herd Improvement program if the crossbreds managed to escape the farmer’s table and end up in the dairy barn.

Crossbred dairy cows were a hot topic in the 1940s and early 1950s due to USDA research, although the idea raised the hair on the necks of purebred dairy advocates.

A 1946 “Hoard’s Dairyman” headline dismissed crossbreeding as akin to “Getting Blood from a Turnip,” and the subject dropped out of sight as the genetically improved Holstein became the industry standard.

Crossbreeding never disappeared entirely, however. A series of studies continued to test the economic advantages, looking for an improved hybrid commercial dairy cow, comparing various crosses with purebreds on the basis of income potential per cow.

Research results remained sidelined for decades until producer interest began to develop very recently, piqued by the success of crossbreeding in New Zealand, and by problems developing with inbreeding, particularly in Holsteins.

Producers have been finding Holsteins harder to breed, and first-calf heifer birthing problems are increasing.

Back in 1939. The first USDA study in crossbreeding began in 1939 and involved two- and three-breed crosses using Holstein, Jersey, Red Dane, and Guernsey.

The study concluded that “female progeny of crossbred cows, when sired by production proved bulls, will develop into very satisfactory dairy cows.” The increase in production attributed to hybrid vigor was about 20 percent.

By the time study results were published in 1954, however, the dairy industry had determined that the Holstein was the commercial breed of choice because of, as the Holstein association asserts, “bulk tank economics; Holsteins produce a better bottom line.”

Subsequent studies of crossbreeding, however, have never really validated that conclusion.

Into the 1980s.

Large, long-term experiments with Guernsey-Holstein, Jersey-Holstein, and Ayrshire-Holstein crosses, tracking milk yield, components, survival, persistence, reproduction, and growth – to establish a total performance profile of crossbreds in comparison to purebreds – provided evidence of positive economic benefits from crossbreeding dairy cattle.

When the USDA’s Agricultural Research Service decided recently to document production results of crossbreds today, they were able to identify DHI life records for only about 40,000 crossbreds born from 1960 to 1991, about 5.5 percent of DHIA recorded births.

Genetic compromise? Currently, there is a growing practice of crossing a Holstein heifer with a Jersey bull to produce a smaller calf that the heifer will be able to deliver without problems.

But, in the end, that practice will compromise the genetic improvement of the herd, said Dianne Shoemaker, northeast Ohio district dairy specialist with OSU Extension.

The newborn calf born to a heifer has the potential of becoming one of the best cows in the herd, Shoemaker said. When that genetic advantage is sacrificed, a whole generation of top herd replacements is lost.

A commercial hybrid.

What dairy geneticists have in mind is more than finding a solution to a specific problem with a few cross breedings.

“I’m convinced,” said University of Kentucky extension geneticist Jack McAllister, “that there is a crossbreeding system that will allow producers to capitalize on the genetic differences of dairy animals.”

McAllister believes a well-designed crossbreeding program can produce a dairy cow that will be more profitable for commercial dairies than the purebred Holstein.

McAllister, who directed a Canadian government crossbreeding study from 1976 to 1986, is fielding an increasing number of questions from producers concerned about the economies of commercial dairying and the decreasing margins on their balance sheets.

“We are not certain whether the increased problems in Holstein reproduction are environmental or genetic,” McAllister said, “but producers are not willing to wait for researchers to find the answer. They are looking for other solutions.”

Canadian study. The Canadian study McAllister directed involved the breeding of 7,000 hybrid animals over three generations, with all matings going back to the original first generation crossbred bulls.

It calculated the annual discounted net return for every female for as long as it lived.

The final result was that the return for the crossbreds was no different than that of the Holsteins, he said, “not better, but not different.”

But McAllister thinks if they had figured net return for each animal over the life of the study and not just for each year, or had even extended that analysis up to 20 years, there would have been a different answer.

His crossbreds did show some hybrid vigor, up to 5 percent, on lactation yield, and they did have a slight reproductive advantage calculated in days open.

The study also turned up evidence that there is a maternal advantage. The breed of the female makes a difference in the amount of genetic influence from each breed that gets passed along.

And even more interesting, he said, the crossbred bulls that came from crosses with a Holstein bull had a 1.6 percent increase in offspring per female, as opposed to bulls from the reverse cross, which had only a .7 percent increase.

On their own. “What do I tell producers who ask me now?” McAllister said. “I tell them to go ahead, but that they will have to conduct their own practical research study. There isn’t a lot of information to guide them, and research findings are now 40 years old. They don’t take the improvements in genetics into account.”

Producers have to decide what breeds they want to cross on the basis of their market.

“Then they have to look and see if their crossbreds produce. They have to look at live calves for their first generation crosses versus their purebreds, monitor their growth and reproduction, keep yield data. The assumption of increased health and increased productive life, often noted for crossbreeds, should also be tested.

“And they have to continue breeding their purebreds in sufficient numbers to provide a meaningful comparison of performance.”

The bottom line. McAllister said crossbreds will not produce as much milk as the Holsteins, even into the third generation of crosses. On the other hand, there may be no loss in fat and protein components.

What producers have to determine for themselves, he said, is what they gain by introducing other genetic factors and in gaining the advantages of heterosis (when offspring have stronger traits than the parents), and if it makes up for loss of milk yield.

McAllister said contrary to expectation and statistical theory, the third generation cows in the Canadian study did not lose their heterosis advantage. Theoretically, it should have been reduced by 50 percent by the third generation.

The American Jersey Cattle Association asserts that gains shown by the growing number of Jersey-Holstein crosses are due not so much to heterosis, which is highly unpredictable, but to the value of Jersey genetics, which have undergone great strides in recent years.

New study. McAllister would like to see a multi-generational, three-breed, back-crossing experiment involving at least 2,500 females and lasting for at least 12 years to determine if the principle of hybrid improvement that has been demonstrated in swine would hold true for dairy cattle.

By crossing each generation of crossbreeds back to a purebred bull in a crisscross pattern that uses a different breed bull for each generation, there should be a way to create a line of commercial dairy cattle that will retain the best of the genetic characteristics of all of the breeds, he said.

(You can contact Jackie Cummins at 1-800-837-3419, ext. 23, or by e-mail at jcummins@farmanddairy.com.)



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Tracking the evidence through DHIA

A USDA dairy geneticist researches the productivity of those crossbred dairy cows already in commercial production.

By Jackie Helstrom Cummins

WASHINGTON – Paul VanRaden, USDA research dairy geneticist at the Agricultural Research Services Animal Improvement Laboratory, has run a few numbers to see what he could find out about crossbred dairy cows in commercial production.

And he decided to do it, he said, “because I felt guilty that we don’t include crossbreds in our genetic evaluations.”

Cows with sire and dam of different breeds are excluded from DHIA evaluations unless identified as part of a breed association “grading up” program.

He searched the DHI data to see what he could find out about crossbreds in general. He wanted to document the number and types of crossbred dairy cattle, and to see what he could find out about breed differences, and then use the information to evaluate the crossbreds on a net merit scale to determine their economic merit.

Selection criteria. The November 2000 test data included records from 16,810 crossbred cows. From these, 12,565 had information on the sire and on the maternal grandparent breeds. The sire was required to have had at least 10 recorded daughters.

He analyzed 10,442 cows in 572 herds containing at least five crossbreds born since 1990. The data came from every section of the country.

The greatest majority of the second breeding of the crossbred cow were backcrosses to Holstein rather than to the other breeds.

When yield data was analyzed, it was found that heterosis advantage was present when the Holstein was the sire. A negative maternal breed effect for Holsteins was suspected but not studied.

The Holstein-Jersey cross showed 7.5 percent heterosis effect of milk production type, a 6.6 percent effect for fat production, and a 7.2 percent effect for protein production. The only higher percentage was for the Holstein-Guernsey cross, which was 7.1 percent for fat.

Productive life. The heterosis effect for productive life, or the period of time the cow stays in the herd, was only about 10 days. Breed differences were actually greater, with Jerseys now slightly exceeding Holsteins for productive life.

VanRaden’s results found no breed or crossbreed could outproduce the Holstein in milk volume, and the protein yield was about equal. The fat yield of the Holstein crosses with Jersey and with Brown Swiss slightly exceeded that of the Holsteins, making these two crossbreds more profitable than the Holsteins when evaluated for cheese yield pricing and with all traits considered.

The analysis did not include any estimate of the economic effect of fertility, calving ease or calf mortality.

There is good reason for the commercial breeder to consider crossbreeding, VanRaden said, although there isn’t any data to predict what might happen a generation or two ahead.

Missing good genes. “I would like to see some ability for other genetics to move into the herd,” VanRaden said. “We are missing out on some good genes from other breeds by concentrating only on purebred Holsteins.”

Crossbreeding, he added, would be a fast way for the dairy industry to work its way out of its inbreeding problems.

A comparison of the highest animals available for selection in each breed will always favor the Holstein, VanRaden said. The best sires available in other breeds did not rank as high as the best available Holstein sires for Holstein cows.

There are at least 93 Holstein sires available now that have a better net merit score than any of the crossbreds.

“That means the elite breeders should keep on doing what they’ve been doing,” he said. “But I don’t see it as a big gamble for the commercial-type farm to be doing some crossbreeding.”

The danger of course, he said, is the possibility of losing genetic progress for the short-term gain in heterosis. Crossbreeding may reduce the cow numbers for the purebreds, a situation that could prove a particular problem for the smaller breeds.

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