Selecting Pasture Proven Profit Driven Genetics
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After making a visual appraisal 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 that reason do not compare adjusted or actual weights between
our Spring and Fall born bulls or cows.
Consider the following:
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 scientifically proven 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. Consequently it is common for our Spring born calves to wean 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
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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. 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 +90 Yearling Weight bull have the genetic potential
to weigh 20 pounds more than calves from a high accuracy +70 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.
