For as long as the beef industry has existed, crossbred commercial cattle have made up the lion's share of the beef cattle population. Now, it seems every publication and expert is talking about heterosis.

"That leads people to ask, 'What's this fancy word "heterosis," and can I capitalize on it in my herd?,'" says Robert Wells, a livestock specialist at the Noble Foundation. "Well, simply put, heterosis is hybrid vigor, or the added advantage in performance of a crossbred over the average of its purebred parents."

So, have producers been doing things right all along and didn't realize it? Well, not so fast …

“There is more to hybrid vigor than just taking a crossbred cow and breeding her with any old bull," Wells says. "Numerous studies have been conducted over the years to look at this very subject. If you want to take full advantage of this phenomenon, there has to be some thought put into the process."

Hybrid vigor is most fully expressed when bulls and cows of known ancestry are used – not just breeding any bull to a cow picked up from a neighbor down the road or bought at the sale barn because the price was right. Work conducted at Texas A&M University by Dr. Jim Sanders has shown a 10 to 20 percentage point increase in calf crop born to F1 cows (a cow which is a first-generation cross between two breeds) when compared to straight-bred cows. The advantage will fall dramatically when F2 (F1 x F1 bred cows), or greater, cows are used.

"One of the most effective and simplest ways for calves to exhibit hybrid vigor is to use an F1 cow and a pure-blood bull of known performance and ancestry; this is what the Foundation livestock specialists have been suggesting," Wells says.

Use of a pure-blood bull allows the producer to have some predictability of how the bull’s progeny will perform. The prediction is made through the bull’s expected progeny differences (EPDs). Breeding a pure-blood bull to a crossbred cow is one way to maximize hybrid vigor. Research has shown, though, that taking crossbred bulls and breeding them with crossbred cows reduces the amount of hybrid vigor that can be expected. This is the reason the Foundation's livestock discipline is recommending an F1-type cow bred to a straight-bred bull of known performance data (EPDs) and ancestry.

"It doesn't matter if you are selling your calves at weaning, as yearlings or retaining ownership through the feedlot; you cannot afford to give up the advantages that hybrid vigor will convey to your bottom line," Wells concludes.

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The Samuel Roberts Noble Foundation (www.noble.org), headquartered in Ardmore, Okla., is a nonprofit organization conducting agricultural, forage improvement and plant biology research; providing grants to non-profit charitable, educational and health organizations; and assisting farmers and ranchers through educational and consultative agricultural programs.