Page 7 - DVAuction Online Catalogs

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Selecting your Genetics
After making a visual appraisal to select those bulls that best fit your unique phenotypic requirements
we highly recommend you use EPDs to determine which bulls best fit your production goals. It must
be remembered that actual weights and measurements cannot be used to compare individuals
across contemporary groups, let alone across herds. A contemporary group is simply a group of
calves of same sex and age that have been handled identically. All actual weights, including birth
weight, can be affected or even manipulated by environment, feed, age of dam, and even at what
point they are taken.
For example:
We could scan our bulls at 18 months and give you actual REA of impressive size.
 Does this make these bulls genetically superior? NO.
It is generally accepted that cold weather prior to calving will increase birth weights.
 Are these cattle genetically predisposed to higher birth weight? NO.
In the Flint Hills of Kansas, fall calves winter extremely hard. The grass is at its lowest protein (4%)
and the weather can be very harsh. On the other hand, spring born calves hit their stride about the
time green grass starts growing. They traditionally will have higher weaning weights when compared
to the fall born calves using identical genetics. It is common for our Spring born calves to wean 100
lbs heavier than our fall born calves due to environment.
 Does this mean our spring born bulls will sire calves with higher weaning weights than our Fall
born bulls? NO.
It would be misleading for us, or any seedstock provider to promote individuals using
actual data.
Comparing across contemporary groups with actual or adjusted data can be inaccurate
and could lead to selection or culling errors. To accurately compare across contemporary
groups and across herds, EPDs are your best tools!!!!
Using EPDs -A common misconception is that EPDs will tell us which animal of several being compared is ‘best’.
EPDs are merely a description of each animal’s genetic makeup. It is up to us to determine which animal is best
for us. What is best for my herd and management situation is not necessarily what is best for your environment,
herd composition and management style.
By correctly using EPDs we can each determine which animal best fits our programs, or moves them in a direction
we want to go. For instance, if your herd is of a heavily muscled continental influence, it may not make sense to
put emphasis on the REA EPD when selecting your Red Angus bull. Your calves may be inheriting all the Rib Eye
size and cutability they need from the dams. On the other hand, if your cows are lighter muscled, British type
cows, you may want to breed towards more cutability and Rib eye size by selecting a Red Angus bull that has a
higher REA EPD. In this scenario, however, it may not make economic sense to pay extra for above average
marbling ability if the cow herd itself is adequate in this trait.
The key to using EPDs is knowing what you have, what you need, and making selections accordingly. A common
misconception is that EPDs are absolute. Calves from a high accuracy +80 Yearling Weight bull have the genetic
potential to weigh 20 pounds more than calves from a high accuracy +60 pound Yearling weight bull at harvest.
Whether they express this added weight depends on if the environment or management, including feed availability,
allows them to. In many cases it may not be worth the extra costs to express the extra genetic potential.