While crossbreeding is not new to the dairy industry, the genomic revolution has helped spark a renewed interest in it as participating dairy producers move toward a more systematic approach.
Crossbreeding not only promotes hybrid vigor and cranks up fertility rates, it gives dairy farmers one more option to match the type of cow they have to their management system and milk market, said Dr. Chad Dechow, Penn State University associate professor of dairy cattle genetics, during the August Hoard's Dairyman webinar, "The New World Of Genetics."
The event, which attracted more than 135 listeners, was co-hosted by Steve Larson, Hoard's Dairyman, and Dr. Mike Hutjens, University of Illinois, and sponsored by Neogen Corp. (www.neogen.com/Agrigenomics)
"If we've gone incorrectly in the past, it's that we've tried to select that cow that suits everybody's purposes and tried to maximize milk yield and type for Holstein cows," Dechow said. "It works well for some management systems and not for others."
For example, a freestall barn with smaller stalls might use crossbreeding with Jersey, Swedish Red and Norwegian Red to create a cow that's a little bit smaller to fit the stalls more comfortably.
On the other hand, a barn with large stalls would lend itself to the use of a larger colored breed, like Brown Swiss. Such a cross would work well, Dechow said, in terms of its competitiveness to pure Holstein cows.
Nearly half of Dechow's widespread audience was using crossbreeding, with 22 percent opting for domestic breeds including Jersey or Brown Swiss; 11 percent using foreign breeds including Nordic Red and Montbeliarde; and 11 percent using both foreign and domestic breeds.
Dechow noted it is difficult to pinpoint exactly how much crossbreeding is happening in the U.S. because not all cows are on an official test program, and, if they are, crossbred data may not be captured completely.
One way of getting a handle on crossbreeding in commercial production, especially for foreign breeds, is to look at semen usage.
In 2004, there was little Montbeliarde or Norwegian Red semen imported and a bit of Swedish Red. The use of Swedish Red spiked to a peak in 2006, when Montbeliarde semen forged ahead before both leveled out at 30,000 units. Of late, there has been a pretty substantial spike in imported Norwegian Red semen
While the numbers are a bit biased because a virus in Europe in 2011-12 limited the import of semen, Dechow interpreted the data as the spikes showing producers trying the particular breed and then those liking it sticking with it. "Now there's a growing interest in Norwegian Red, and we'll see where that levels out," he said.
Dairy producers now have a sense of what they should expect in daughter performance by crossing with the three particular foreign breeds.
"Some of these bulls that we've imported actually have enough daughters that they have an official U.S. genetic evaluation," Dechow said.
Researchers looked at how the bulls performed on a Holstein scale, adding hybrid vigor into the equation.
The data showed Montbeliarde, Norwegian Red and Swedish Red daughters would not produce as much as a typical Holstein but would be very competitive for fat and protein and quite a good for somatic cell count. Bear in mind that the Holstein bulls used would be very high in PTA milk, high for fat and protein and very favorable for somatic cell score, Dechow pointed out.
Where the Holsteins can't keep up is in the fertility column. "The fertility rates for the foreign breeds were pretty much off the charts, compared to the very best Holstein bulls," Dechow observed. "So what we have is these foreign breeds are maybe not elite for fat and protein, but reasonably competitive, with a big boost in fertility levels."
There are a lot of ongoing research trials, including one in Minnesota looking more closely at Montpelier and Swedish Red. "Over time, we'll have an even better way to compare these crosses, but I think, based on research results I've seen, this fairly well represents what we should expect — in particular, a big jump in fertility when we start to crossbreed," he added.
While the foreign breeds get a lot of attention because they are a bit unique and different, crossing with more common domestic colored breeds can also work in multiple situations.
Dechow referenced a USDA study on Brown Swiss and Jersey cows from 2006, detailing the difference in net merit and cheese merit on a Holstein base. On a net merit basis, the first-generation Jersey/Holstein and Brown Swiss/Holstein crosses were very competitive with purebred Holsteins.
The oft-poised question then is what to do after that first generation.
"Hopefully, we think that through before we actually go down that road," Dechow observed.
There are a couple of options in a net merit scheme. One is adding a third breed to the rotation, especially if pounds of fluid milk is viewed as more valuable.
"While Holsteins still outperform the three breed rotation, after we got out into the cross — Holstein x Brown Swiss x Jersey — those cows perform very well," Dechow said.
Based on the date, a three-breed rotation is generally recommended.
"We use three-breed rotations because it helps us keep high levels of hybrid vigor for fertility and health, but at the same time, keep enough of that Holstein influence in there to keep production levels fairly high," Dechow explained.
On the cheese merit side, where protein and fat are more valuable, three-breed crosses tend to do fairly well, compared to, for example, breeding a Holstein to a Jersey and then breeding that first generation cross back to a Holstein.
There have not been a lot of head-to-head comparisons for the different breed combinations.
"We've seen different crosses compared to Holsteins in research trials and research herds, but we haven't seen, for example, Holstein/Montbeliarde crosses compared directly to Holstein/Brown Swiss crosses," Dechow said.
That lack of direct comparison of particular combinations makes concrete crossbreeding recommendations a bit tricky — a situation Dechow expects to last. While it will take a long time to fill in the puzzle pieces because there is just not enough research in the area, he's convinced the results of the last few years illustrate the merit of using crossbreeding to fire up fertility and better match dairy facilities and milk markets.
"The poultry and hog industries really take advantage of crossbreeding, and I think it's something we'll see more of in the future of dairy as well," he concluded.