  BeefTalk:
Data Study Helps Evaluation of Moderate Framed Beef Cows
By Kris Ringwall, Extension Beef Specialist,
NDSU Extension Service
As the bull buying season continues, it’s critical that producers define how
they want their future calf crops to look. The North Dakota State University
Dickinson Research Extension Center has used a pool of 21 AI Angus bulls in
recent years. As new bulls become available, bulls are added to the pool and
others are removed.
Throughout the years, consistent use of certain bulls helps us measure
genetics over different environmental conditions. Weather conditions directly
affect calf crop performance but calves sired by the same bull over time have
very similar genetics and allow us to evaluate performance under various
conditions.
Our cow herd is primarily a combination of black, black baldies, red baldies
and red-colored cattle. The color patterns do not imply the actual performance
of the herd, so I will also note, according to last year’s CHAPS analysis, the
cows weighed 1,279 pounds at weaning with a 4.9 frame score.
The herd produced steer calves weighing an average of 543 pounds at weaning
and heifer calves weighing an average of 506 pounds at weaning. In general,
these cows are slightly smaller than typical cows (frame 4.9 versus 5.3),
slightly lighter (1,279 pounds versus 1,306 pounds), and wean slightly lighter
steer calves (543 pounds versus 555 pounds) and slightly lighter heifers (506
pounds versus 530 pounds).
Without going into immense detail, our objectives are being met with these
cows. We maintain a medium-framed, medium-weight cow herd.
One of the questions we deal with is whether to stay with the current pool of
AI Angus bulls or add new genetics. In general, the current pool of AI bulls has
sired calves seven pounds lighter in birth weight than the average calf in the
herd, and eight pounds heavier at seven months of age. The trend is an excellent
one to maintain and was accomplished by restricting birth weight EPD (Expected
Progeny Difference) to two pounds or less and selecting moderate-growth bulls
with weaning weight EPDS of +25 to +48 pounds.
Recent additions to the pool have focused on working the weaning weight EPDs
into the low 40s. The question that rolls through my mind deals with whether or
not there is enough growth in this herd to justify retained ownership of the
calves.
Glancing at the first few years of carcass data, the first additions to the
bull pool averaged more than 3.25 pounds average daily gain. Some of the recent
bulls have averaged more than 3.5 average daily gain. In fact, the most recent
additions are averaging more than four pounds average daily gain in the feed
yard.
What I found interesting, by focusing on moderate growth with low birth
weight, was that feedlot gain did not suffer. This does not mean feedlot gain
could not be improved. Adapting a cow herd means controlling cow size,
eliminating birth problems and still pushing growth, the No.1 profit indicator.
For this year, without boring you with several more pages of data, the Angus
bull selection thresholds for the Center are becoming clearer. The birth weight
EPD needs to be less than +2 pounds, the weaning weight EPD needs to be greater
than +40 pounds, the yearling weight EPD needs to be greater than +74 pounds and
yearling height less than +.7. Keeping the upper 30 percent of the breed for
milk, ribeye area and marbling would round off the sire selection. So much for
the window shopping, I need to get some semen ordered.
May you find all your ear tags.
Your comments are always welcome at www.BeefTalk.com.
For more information, contact the North Dakota Beef Cattle Improvement
Association, 1133 State Avenue, Dickinson, ND 58601 or go to www.CHAPS2000.COM
on the Internet. In correspondence about this column, refer to BT0135.
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Source: Kris Ringwall, (701) 483-2427, kringwal@ndsuext.nodak.edu
Editor: Tom Jirik, (701) 231-9629, tjirik@ndsuext.nodak.edu
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Graphic --
EPD Selection Threshold Goals for AI Angus Sires
NDSU Dickinson Research Extension Center
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Birth weight less than + 2 lbs
Weaning weight greater than + 40 lbs
Yearling weight greater than + 74 lbs
Yearling height less than + .7
Milk greater than + 20
Carcass ribeye area greater than + 0.20
Carcass marbling greater than + 0.15
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