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Watch Extremes
ELDON COLE
MT. VERNON, MO.
In my career I’ve seen a lot of changes in beef cattle breeding habits. As a young person in the 40’s and early 50’s the emphasis in beef cattle was placed on producing what was called “baby beef.” Cattlemen wanted calves to be thick and deep. The deeper and thicker they were, the better. Two genetic problems arose from this drive and they were dwarfism and double muscling. Each condition was bad and caused numerous herds to disperse due to “dirty” pedigrees and the recessive gene carrier animals.
These problems disappeared and over a number of years thanks to more moderate selection practices on frame and thickness. Much of this trend began about the time I graduated from college. The scale, frame measuring sticks and performance testing became tools of the trade for most breeders. In the mid-60’s and 70’s it seemed the British breeds were stuck in the 2, 3 and 4 frame score range.
The barrier was finally broken and 5 and 6 frames became numerous. In commercial herds European breeds boosted frame scores beyond that as crossbreeding was used extensively. I remember the largest frame bulls sold at the state tested bull sale in 1987-88 were Simmentals that were 10 plus. I’m sure in the 60’s there were 1 frames among comprest or dwarf carrier animals. Since each frame change represents 2 inches, going from a 1 to a 10 means a 20 inch increase in hip height at the same age.
The use of objective measurements in selection is important and today we can change cattle much quicker than we did thanks to genomics, objective measures and expected progeny differences (EPDs). This is good but could be bad if not used wisely. The bottom line is, be cautious in selecting extremes. Sure, that extreme animal helps bring change quicker but EPDs are powerful and will bring about change more quickly than you might imagine.
Extremes aren’t just about frame size and visual thickness. They’re about calving ease, birth weights, milk, ribeye size and scrotal circumference. The term “middle-of-the-road” may be a wiser choice to make as you make breeding decisions. I hear many saying selection for extremes in calving ease is resulting in smaller calves at birth and that carries through in weaning weights. ∆
ELDON COLE: Extension Livestock Specialist, University of Missouri
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