Tough Fit--Technology helps, but genetics are the key to improving tenderness

If the beef industry wants to win back lost market share - 20% in 20 years - it will have to do more than try a little tenderness with consumers. Producers will have to select directly for the trait."We found you can make some improvement using technology, but you can't get where you want to be. If you start with sorry old stuff, that's where you end up," says Daryl Tatum, a Colorado State University

If the beef industry wants to win back lost market share - 20% in 20 years - it will have to do more than try a little tenderness with consumers. Producers will have to select directly for the trait.

"We found you can make some improvement using technology, but you can't get where you want to be. If you start with sorry old stuff, that's where you end up," says Daryl Tatum, a Colorado State University (CSU) animal science professor.

Tatum is describing the results of a palatability study funded by the National Cattlemen's Beef Association (NCBA) two years ago that sought to identify management schemes for improving tenderness. (See BEEF, March 1998, page 14). By some accounts tenderness is the reason beef fails the consumer as much as 25% of the time.

"Just using postmortem technology, the probability of getting a product that wasn't acceptable was 13 percent for sirloin strips and 12 percent for top sirloin," says Tatum. "When we added genetic intervention, we improved to 4 percent for the top sirloin and 1 percent for the sirloin strip steaks."

In other words, technology, like high voltage electrical stimulation and injecting beef with calcium, can reduce the failure rate. But selecting tender genetics, identified by Warner-Bratzler shear (WBS) tests and sensory panel evaluation, significantly improved product reliability.

What's more, there is enough genetic variation within breeds and between breeds to make significant genetic progress. As an example, the Conception to Consumer Study completed by Texas Tech University (TTU) last fall discovered just how much tenderness variation existed between 90 sires representing 11 different breeds.

With seven days aging on the carcass, researchers found 11 bulls that sired progeny with shear tests of 4.5 kg or more. According to TTU meat science professor Mark Miller, at that level the product would be unacceptable to at least 64% of consumers.

With the same aging, only seven bulls sired progeny that sheared at 3.0 kg or less, a level Miller says would provide 100% consumer acceptance. The bulls in between offer progeny with varying degrees of product success. For example, at 4.0 kg Miller says the product is acceptable to 89% of consumers.

Along the way, Miller and his crew also discovered, like other forms of post-mortem technology, aging improves tenderness, but it won't make a silk purse out of a sow's ear. Aging carcasses for 21 days in the study significantly enhanced tenderness, moving some from marginal to acceptable.

Aging Has Its Limitations But, Miller says, "The aging of beef will not be an effective treatment for removing tough beef from the system. The industry will have to remove these sires and their progeny that produce tough beef from the production population through genetic selection."

Bottom line, Miller says, "The study told us we definitely have variation between different sires and that we can select genetics to improve beef tenderness."

In fact, Ronnie Green, CSU animal science professor, says the heritability estimate for tenderness runs 0.20-0.45, depending on the breed, or about 0.30 for an average. So, progress can be made.

The problem is unless seedstock producers progeny test each bull - a costly multi-year process - there is currently no way to select directly for tenderness.

A New Approach The need and challenge are easiest to understand in the real world. By 1991 the R.A. Brown Ranch at Throckmorton, TX, knew that serving their bull customers and the industry meant adding carcass merit to selection decisions. The Browns have eight different breeds, including three hybrid crosses and a composite. They market 450 bulls each year.

"We don't have to measure carcass traits, but we have to compete with others who do," says Donnell (pronounced Donald) Brown. Likewise, he explains the beef industry doesn't have to get a handle on product quality, but it must compete against other meats that already have.

"Post-harvest management is wonderful, but ignoring the genetic side of tenderness would be like ignoring calving ease because you have calf pullers, or ignoring growth traits because you have growth implants," says Brown. But how?

Brown says, "We still believe growth is the most important profit factor in the current pricing system; we still get paid by the pound, so we've been reluctant to give up growth or reproductive efficiency for carcass merit." The same goes for reproduction.

With that in mind, the Browns began collecting their own data in 1991. By 1996 they felt confident enough in their information that they could start selecting for carcass merit without sacrificing other important traits.

Today, they weight maternal, growth and carcass traits equally in selection. "There must be a focus on balanced trait selection, but we must focus on eating quality, too," says Brown.

For other producers trying to make sense of this, Brown has some straightforward advice he shares with customers: "The first rule is that cows have to fit the environment. Next, select bulls that fit the market. Then, select a breeding system that fits your management."

When it comes to selecting for eating quality, the Browns, must rely on marbling EPDs. "Marbling helps us with flavor and is an indicator of juiciness and tenderness, but it's not a 1:1 correlation," says Brown.

Are Marbling EPDs An Answer? For the record, Tatum says marbling does explain 5-30% of the variation in tenderness, depending on the study. But, he explains, since over 80% of the cattle harvested in the U.S. fall into the Choice and Select quality grades, there is too little marbling variation to use as a genetic predictor of tenderness.

In the future, Brown hopes there will be tools to use in selecting for tenderness, specifically. "We support the NCBA Carcass Merit Project and believe it is a must. We believe there are tender cattle in all breeds; it's a matter of finding them and mass-multiplying them."

The project Brown mentions is the industry's first real attempt to establish genetic selection tools for tenderness. "The first basic objective is to lay out a method for people to collect data for meat quality. In other words, this is what it will take to get tenderness EPDs," says Green, who serves as breed association liaison for the project.

The 42-month study includes bulls from 16 breeds and will encompass approximately 11,000 head of cattle sired by these bulls. Carcass data, including shear forces, will be collected on each one, with sensory panel work conducted on enough of them to establish tenderness EPDs for each breed.

"Second, the project will evaluate whether the DNA markers identified in the carcass gene mapping study, conducted at Texas A&M University and funded by beef checkoff dollars, will hold up across breeds," says Green.

In that study, researchers identified 10 gene markers which impact carcass merit in Brahman and Angus cattle. This project will determine whether those same markers will work in other breeds.

"Regardless of whether the markers hold up between breeds, during the course of the study I'm hopeful Jerry Taylor and Scott Davis (A&M researchers) will uncover what the specific genes are," says Green. He explains the markers are located next to the gene in question. If researchers can locate the gene, there is no more need for markers.

Either way, by the end of the study tenderness EPDs should be available. Green says the DNA adds accuracy to a tenderness EPD constructed with WBS and sensory panel data.

The Cost Of Carcass Merit Finally, Green says, "The third area of the study, which may have as much or more value to breeders, is Steve Koontz's, a CSU ag economist, looking at what costs are associated with obtaining this information. He'll predict the costs of creating the EPDs, and what the economic value is of having this information in the industry."

Indeed, the bottom line that necessitates getting an industry handle on tenderness should also drive individual producer decisions on how they incorporate carcass merit in their own herds, if they do.

Jerry Lipsey, executive vice-president of the American Simmental Association, which was an instigator of the Carcass Merit Project asks, "Is there a reasonable chance producers could or should get rewarded for tenderness?"

While there may be no such thing as a tenderness premium today, he explains, "The way all of this alliance formation and partnership building is going, certainly out there in the future, and it may not be very distant, some distributor of beef will say, 'If you're in a program of genetically improving your beef, we want to be a part of your program.' "

At the very least, tenderness tools should help producers identify whether sires can be part of the industry solution. For instance, the Browns had a chance to put some of their Hotlander cattle, a composite they designed - Brahman, Senepol, Simmental, Red Angus - in the CSU project. They already knew these cattle were grading 65% Choice and were 70% yield grade 1 and 2. What they didn't know is how the tenderness would stack up.

Despite the pounding Bos indicus genetics have taken over tenderness, they discovered their sires produced tender carcasses. They also found sire variation through the TTU study.

That's the power of the reality unearthed by TTU and CSU researchers in their respective studies. "It wasn't a breed issue, it was a sire within breed effect that was important. It was the sires, irrespective of the breed," says Tatum.