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Finally, there's general agreement that data generated by ultrasound on
yearling bulls to predict carcass traits on their slaughter progeny is as
accurate, and much faster, than collecting carcass data in the
packinghouse. As a result, using ultrasound data to calculate carcass EPDs
(expected progeny differences) has breed associations signing up. The American Angus Association (AAA) began collecting such data in January,
says John Crouch, AAA director of performance programs. Their first set of
carcass EPDs from ultrasound will be published this fall. The Angus program is called 'Triple A Cup,' for AAA Centralized Ultrasound
Processing laboratory (AAACUP). The program originated two years ago when
AAA officials, concerned about the accuracy of image interpretations, asked
Iowa State University (ISU) scientists Doyle Wilson, Gene Rouse and Scott
Griener to develop a centralized processing laboratory. Its staff would
interpret ultrasound images. Under AAACUP, a breeder selects a qualified technician from a published
list who comes to the ranch and collects ultrasound images on yearling
bulls, heifers or their progeny. The images go to the ISU laboratory in
Ames, IA. There, Craig Hays and his technical staff interpret all images
for ribeye area, rib and rump fat thickness, and intramuscular (IM) fat
(marbling). The data goes back to the association where age adjustments are
calculated. Brangus Was First
In 1995, the International Brangus Breeders Association (IBBA) was the
first to publish a carcass EPD for ribeye area based on ultrasound
measurements of yearling bulls. Fat thickness and IM fat EPDs were
published on their Web site a few weeks ago, according to Loren Jackson. Last fall, the American Hereford Association (AHA) published its first
genetic analysis using ultrasound as a supplement to its sire summary. It
was a multiple-trait animal model combining weaning weight, fat thickness,
ribeye area and percent IM fat EPDs. Some 9,500 yearling cattle, mostly
bulls ranging in age from 330 to 430 days -- adjusted for age and age of
dam -- were measured to procure the data. Until now, most ultrasound research has been on English cattle. That will
change soon as other breed organizations, including American International
Charolais, North American Limousin Foundation (NALF) and American
Simmental, get on board. 'We're in the process of getting organized to collect ultrasound data,'
says Robert Williams, Charolais director of breed improvement. 'Hopefully,
we can do it one to two years.' The NALF board of directors recently voted to develop centralized
processing services for its members. 'AAACUP is what we want to work
through,' Kent Anderson, director of education and research, says. Anderson likes the idea of centralized processing. 'It would be easier if
all data came in the same format so we could process it electronically
rather than hand-punch it,' he says. The association has calculated experimental EPDs for the three traits on a
couple of thousand records, but hasn't decided when to publish them. 'If we could add another 2,000 records on yearling bulls, females and
steers, we could publish it as early as next fall and perhaps put out a
research report later this spring on some of our more accurate bulls,'
Anderson says. Simmental officials say the depth of their records will determine their
entry. 'Our goal is to eventually merge ultrasound with actual carcass data
into one evaluation,' says research director Bruce Cunningham. Two Options With Ultrasound Currently, breeders have two options: *AAACUP with its centralized processing, or *Individual technicians certified in one of the AUP (Association of
Ultrasound Practitioners) training schools for one or more of four
procedures: fat thickness measured at the 12-13th rib, rump fat, ribeye
area and percent IM fat. This new centralized processing concept has raised discussion about who
should process the images. So far, Angus, Limousin and Simmental use
AAACUP; Brangus and Hereford use individual certified technicians. AAACUP doesn't require every technician to be AUP certified, but they'd
like to see them go through the school, says Wilson. 'It's good training,'
he adds. 'With centralized processing, if someone has a problem on a trait,
we can correct it because we oversee every image they collect.' Wilson advocates centralized processing for two reasons: *Improving the uniformity of interpretation and quality checking of
technicians, and *Data collection and identification of contemporary groups. 'It is critical that the image is selected properly and processing done
correctly,' he says. 'We have trained people to do that quickly and
efficiently.' Kansas-based Matthew Lane was one of 14 certified on the Aloka 500 with its
17.2 transducer and Critical Vision software for all four. He's also on the
AAACUP list and has qualified under CPEC (Cattle Performance Enhancement
Company), a system designed by scientist John Brethour of Kansas State
University. CPEC is used primarily for sorting feedlot cattle to a common
slaughter endpoint. Lane scans cattle from Texas to Montana using both systems. He thinks
AAACUP works well, but there's still need for AUP certification. 'I'd prefer a technician involved in this program also goes through AUP
certification for a couple of traits,' he says. 'They would better
understand what's involved when these images go to the lab for
interpretation.' University of Missouri animal scientist William Herring works closely with
the AHA program. He believes ultrasound technology has improved and is
cheaper than gathering carcass data. 'But it's still expensive,' he adds.
'Competition among technicians can keep costs down.' As Good As Carcass Data
Regardless of the discussion over procedures, there's general agreement
that ultrasound techniques are as good as carcass data and visual grading. Gardiner Angus Ranch has collected feedlot and carcass data since 1970.
Today, they use ultrasound to measure backfat, ribeye area and percent IM
fat on all yearling bulls. 'It lets us test thousands of bulls instead of hundreds as we did with
carcass collection on progeny in the packing house,' says owner Henry
Gardiner. 'We can find outliers in relatively short time.' The ranch's goal is to produce genetically superior bulls for the
commercial industry. The only criterion for improvement is knowing exactly
how your cattle perform, not only through genetic selection, but in the
feedlot and on the rail. That same philosophy occurs at the 10,000-acre Camp Cooley Ranch near
Franklin, TX. In 1993, ranch owner Klaus Birkel bought the well-known
Brinks Brangus purebred herd at Eureka, KS. The Brinkmans were among the first to use real-time ultrasound to measure
backfat and ribeye area on yearling bulls and heifers. Klaus continued that
program -- a contributing factor in IBBA being the first to publish ribeye
area EPDs. 'Carcass merit is more important today than ever before,' says ranch
manager Mark Cowan. 'But we believe if you don't keep that trait in balance
with the other important economic traits, you're not helping your customers
or yourself.' The American Angus Association (AAA) has set up the following AAACUP
guidelines for scanning yearling bulls: *Contact John Crouch, AAA director of performance programs, at 816/383-5100
at least three weeks prior to scanning date for instructions and a list of
certified technicians. *Identify all animals to be scanned so barn sheets can be available at the
farm or ranch the day of scanning. *All yearling bulls in a contemporary group are scanned no more than two
days apart at 320 to 440 days of age. Individual bull weights must be taken
within seven days. *Each bull contemporary group must have two sires represented. One must be
a reference sire in the Angus structured sire evaluation program for
carcass merit. Central-test scans will not be accepted unless bulls are
maintained in their weaning contemporary group. *The technician bills you for the trip to the ranch to get ultrasound
images. This doesn't include interpretation of images, which is done in
Ames, IA, at an add itional charge. *Processing follows the same format used for weight traits with the Angus
Herd Improvement Records. Ultrasound measures are adjusted to 365 days for
yearling bulls, with end-point adjustments for developing heifers, feedlot
steers and heifers at 420 days.
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