Page 9 - MWC 3-31-2022s

The Impact of Bull Selection –Part 1 The Midwest Cattleman · March 31, 2022 · P9

By Mark Z. Johnson

Let’s take a look at an ex- In this example, we use
ample of what happens to ex- herd bulls as rotational
pected herd performance in sires, selecting the best 20%
the next generation based on of heifers to develop as re-
the bull we use. placements, and sell all other
First, last fall at weaning calves at weaning.
we took the following mea- Since genetic values are
sures of herd performance. comparable across time and
•1,400-pound average ma- geography, we can use the
ture cow size (4 – 7 year old registration numbers of the
cows) continued on page 13
•85% pregnancy rate
•82% calf crop weaned
•Average weaning weight
500 pounds
•Pounds of Calf Weaned/
Exposed Female = 410
This data indicates that we
need to improve the Pounds of
Calf Weaned/Exposed Female
on a whole herd basis to im-
prove the profit potential of
this operation. Traits of eco-
nomic significance to improve
this number are weaning
weight, cowherd fertility, cow
milk level and mature weight
of cows. An EPD exists for
each and can be used as a
basis of selection to improve
the 410 value.

Callaway

Livestock

Center, Inc.

On I-70, 4 miles east of
Kingdom City, MO on outer road

573-642-7486

Feeder Sale

Monday
12:30 p.m.

1st Thursday Night
of Each Month

6:00 p.m.

Special Cow Sale

Jack Harrison
573-386-2138

John P. Harrison

573-386-5150