Difference between revisions of "Ultrasound rib eye area"

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     E.g., for birth weight discuss digital scale, mechanical scale, hoof tape, etc.
 
     E.g., for birth weight discuss digital scale, mechanical scale, hoof tape, etc.
 
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Accurate  live  animal,  ultrasound  estimation of  ribeye  area  is  dependent on three major items: clear and distinct medial and lateral end borders, not being over any  portion  of  12th or  13th rib,  and  good  transducer-animal  contact.    The  presence  of well-defined  intercostal  muscles  under  the  longissimus  dorsi  is  an  indication  that  the transducer  is  properly  aligned  directly  between  the  12th and  13th ribs  for  this measurement. Ultrasound technicians and image processing labs should be certified or accredited by the Ultrasound Guidelines Council.
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Accurate  live  animal,  ultrasound  measurement of  ribeye  area  is  dependent on three major items: clear and distinct medial and lateral end borders, not being over any  portion  of  12th or  13th rib,  and  good  transducer-animal  contact.    The  presence  of well-defined  intercostal  muscles  under  the  longissimus  dorsi  is  an  indication  that  the transducer  is  properly  aligned  directly  between  the  12th and  13th ribs  for  this measurement. Ultrasound technicians and image processing labs should be certified or accredited by the Ultrasound Guidelines Council.
  
 
===Adjusted Value===
 
===Adjusted Value===
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===Contemporary Group===
 
===Contemporary Group===
 
<!-- Discuss how contemporary groups are formed -->
 
<!-- Discuss how contemporary groups are formed -->
Animals of the same  sex,  reared  and  managed  together  up  until  the  time  of  scanning  form  a contemporary group.  Scanning  contemporary group  definition  includes  the  following:  herd  code,  weaning  date, weaning  management  group  (pasture,  creep,  non-creep,  etc.), scanning  date,  and  post-weaning  management  group  designation.  For  animals  scanned  at  a  central  test,  the  contemporary  group  definition  for  an  animal should  include its  herd  of  origin  and  other  birth  and  weaning  contemporary  group information.
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Animals of the same  sex,  reared  and  managed  together  up  until  the  time  of  scanning, form  a contemporary group.  Scanning  contemporary group  definition  includes  the  following:  herd  code,  weaning  date, weaning  management  group  (pasture,  creep,  non-creep,  etc.), scanning  date,  and  post-weaning  management  group  designation.  For  animals  scanned  at  a  central  test,  the  contemporary  group  definition  for  an  animal should  include its  herd  of  origin  and  other  birth  and  weaning  contemporary  group information.
  
 
===Genetic Evaluation===
 
===Genetic Evaluation===

Revision as of 11:08, 23 December 2019


Accurate live animal, ultrasound measurement of ribeye area is dependent on three major items: clear and distinct medial and lateral end borders, not being over any portion of 12th or 13th rib, and good transducer-animal contact. The presence of well-defined intercostal muscles under the longissimus dorsi is an indication that the transducer is properly aligned directly between the 12th and 13th ribs for this measurement. Ultrasound technicians and image processing labs should be certified or accredited by the Ultrasound Guidelines Council.

Adjusted Value

Ultrasonic ribeye area is adjusted to a common age (e.g., 365 days of age), and in multiple-breed settings is also adjusted for breed composition and heterosis.

Contemporary Group

Animals of the same sex, reared and managed together up until the time of scanning, form a contemporary group. Scanning contemporary group definition includes the following: herd code, weaning date, weaning management group (pasture, creep, non-creep, etc.), scanning date, and post-weaning management group designation. For animals scanned at a central test, the contemporary group definition for an animal should include its herd of origin and other birth and weaning contemporary group information.

Genetic Evaluation

Given the ultrasound measure of ribeye area is an indicator of the economically relevant trait of carcass ribeye area, it is generally included in multiple-trait models that include carcass ribeye area and potentially other traits such as carcass weight. There are no maternal effects fitted for ultrasound or carcass traits given the maternal influence declines post-weaning.

Usage

Ultrasound ribeye area is an indicator trait that is measured on seedstock animals. It is used to help predict the genetic merit of animals for carcass ribeye area. The majority of beef breed organizations do not publish an ultrasound ribeye area EPD but rather publish an EPD for carcass ribeye that is the product of a multiple-trait model including the ultrasound indicator trait.