By Gary Sliworsky
Ag rep, Emo
As cattle producers start to think about purchasing bulls and gear up for another breeding season, they need to remember the power of cross-breeding.
The boost in performance that comes from cross-breeding is called heterosis, and sometimes is referred to as “hybrid vigour.”
Many producers don’t take advantage of this heterosis. In fact, there are some very popular breeds and many commercial producers who essentially are straight-breeding.
The real value of cross-breeding is in the cross-bred cow. Commercial cattle producers need to take advantage of this maternal heterosis and plan for it as they develop their breeding programs.
Cross-breeding probably is one of the few tools commercial cattlemen can use which costs nothing and can provide high returns.
Over the last two decades, poorly-managed or unmanaged cross-breeding systems probably have decreased returns in some commercial operations, and tended to increase (rather than decrease) variability in beef cattle.
As such, many commercial cattlemen have abandoned cross-breeding in an attempt to simplify management or undo past mistakes.
However, the value of a good cross-breeding system cannot be overlooked. Individual heterosis is the increase in productivity that occurs when producing a cross-bred calf from a purebred sire and a purebred cow.
Maternal heterosis is the increase in productivity achieved by using this cross-bred calf as a cow in your herd.
U.S.D.A. researchers found that individual heterosis could boost weaning percentage by three percent, and maternal heterosis could increase that value by 6.4 percent for a total increase of nearly 10 percent.
For weaning weight per cow exposed, scientists saw a total increase of more than 23 percent when individual and maternal heterosis were taken into account.
Beef production traits that typically benefit most from heterosis are those that are related to fertility. Those traits also aren’t usually strongly related to genetics.
These are typically traits such as cow fertility, weaning percentages, survival, and other traits which tend to be influenced by the environment.
Researchers found that traits like calving rate, calf survival to weaning, and weaning rate benefited most from heterosis. However, heterosis had little influence on cutability, quality grade, ribeye area, or mature cow weight–traits that are strongly influenced by genetics.
Place all of this in the context of your farm management system as you select bulls.
Even with the increased emphasis on carcass traits that we see in the industry today, cow fertility still is the single-most important trait influencing the productivity and profitability of your herd.