Carcass Shows
&
Ultrasound
Bernie O’Rourke
& Ron Russell
UW - Madison
Gary Onan &
Dewey Wachholz
UW – River Falls
Types of Evaluation


Visual Appraisal (What do they look
like) Estimation with our eye Judging
Carcass Merit – Carcass Shows
• Actual measurements
• Sometimes we can’t see carcass

Machines to measure carcass traits
• Carcass traits area highly heritable.
Why collect carcass trait
information?



Youth project development of meat animal
projects should include information on
how their animal is viewed as a food
product (too fat, too lean, didn’t grade
(Beef), etc.
Without carcass trait information, youth
will not know how to improve their project
in the future
Reminder that youth are a producer of
food – should be as ideal as possible.
Method of Evaluation
Neither
Both
Ultrasound
Carcass Show
0
5
10
15
20
Counties Reported (52 of 72)
25
30
Who ranks the data – Ultrasound
Sent to someone else
Show committee
Technician
0
2
4
6
8
Counties Reported
10
12
14
16
18
Criteria Used Ultrasound - Lambs
other
Value gain/day
Lamb Carcass Index
%BCTRC
0
2
4
6
Counties Reported
8
10
12
14
Criteria Used Ultrasound - Pork
other
lbs. lean gain/day
% fat free lean
0
2
4
6
Counties Reported
8
10
12
14
Criteria Used Ultrasound - Beef
other
Value gain/day
Combination QG & YG
0
2
4
6
Counties Reported
8
10
12
14
Carcass Show - Advantages



Provide the opportunity to educate youth
of another segment /final segment of the
livestock industry
Presents the actual carcass on the rail
allowing the participants to truly see the
compositional traits of their animals
Provides objective evaluation of livestock
via provision of absolute / accurate
carcass measurements (depending on
expertise of evaluation) allowing the
assessment of carcass value
Carcass Show - Advantages
cont.
• Carcass composition is directly
assessable, allowing for more accurate
and complete evaluation of lean quality
• Develops more confidence in the
producer to consumer chain—
community development
• Facilitates community development via
two-way interaction with local business
operator / retailer
Carcass Show Disadvantages




Requires additional help—this can,
however, be a great educational tool
Requires the presence of and the
cooperation of one or more locker
operators
Can be traumatic to some individuals –
balance against value of reality education
and experience
May be viewed as “evaluation” of live
show and judge quality while carcass
shows only measure the “carcass”
Ultrasound



A Live Animal Tool to measure VALUE
Provides estimations of what the carcass
characteristics may be (fat thickness,
ribeye or loin eye measurements, etc…)
without harvesting the animal.
However, there is some error
• Good technicians correlations with carcass
measurements are typically .85-.90
• Marbling measurements typically result in
same grade as carcass or 1/3 grade deviation
Ultrasound

Pork quality
• Ultrasound cannot measure color or
firmness
• Some technicians can measure
intramuscular fat (marbling)
How does ultrasound work?

The probe puts out high frequency sound
waves which pass through tissues at
different rates
Air
330 m/s (meters/second)
 Fat
1430 m/s
 Water
1500 m/s
 Muscle
1620 m/s
 Bone
3500 m/s
At each change in tissue density, some waves
reflect back and some continue through the
animal.
Frequency and intensity of the reflected waves
generates an image portrayed on the screen.



B-mode Ultrasound system


Moving animals
Dirty animals
don’t get a good
imagine
Applications for Ultrasound

Breeding Stock
• Tool for making genetic improvement
• Select superior animals
• Generate Expected Progeny Differences

Feedlot
• Sorting cattle into market groups
• Estimate days on feed
• Maximize economic returns

County Fairs
Carcass Measurements
Summary of Ultrasound

Advantages
• Doesn’t require meat plant
• No need for further fair staff work the
following week
• Results available for market animal sale
• Results may be more accurate in
situations where the:


plants strip significant fat during hide, skin
or pelt removal
plants must hot-rib
• Results may be more comparable

shows where multiple plants are used
Summary of Ultrasound

Disadvantages:
• Significant time required at fair to
collect data—especially for cattle
• Increases cost of show—technician fees
• Results may be inaccurate
• Pork quality is not determined
• Exhibitors have no opportunity to see
carcasses
• Limited opportunity for explanation of
data to exhibitors
Things to think about…

What are your program goals?
• Carcass data ranking
• Performance/”Value added” ranking

Carcass winners and value added winners
will seldom be the same carcass
• Carcass champions may not come from
efficient/productive market animals
• “Value added” champions may not exhibit
“ideal” carcass characteristics.
Comments from survey

Don’t hand out information before
the live judge evaluates the show