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Back Fat Thickness: Difference between revisions
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[[Category:Carcass Traits]] | |||
Back fat is an estimate of external fat, which is the most important factor in determining retail [[Yield_Grade | yield percentage]]. | |||
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Place brief trait definition/description here | Place brief trait definition/description here | ||
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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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Back fat | Back fat is measured at the 12th rib, perpendicular to the outside fat at a point three-fourths of the length of the ribeye muscle from the backbone. As external fat increases, the percentage of retail product decreases. | ||
===Adjusted Value=== | ===Adjusted Value=== | ||
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If the trait is not adjusted (e.g. Stayability) then say so | If the trait is not adjusted (e.g. Stayability) then say so | ||
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This measurement is often subjectively adjusted at the time of data collection to reflect unusual fat distribution of the carcass. The adjusted back fat thickness is then reported on an age-constant basis. | |||
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===Contemporary Group=== | |||
<!-- Discuss how contemporary groups are formed --> | <!-- Discuss how contemporary groups are formed --> | ||
A contemporary group is a set of cattle of the same sex that have been raised together and have received equal treatment up to the point of slaughter. All progeny within a contemporary group should ideally be born within a 90-day period, and male calves must be castrated. A contemporary group up to the time of weaning will be subdivided if some cattle go on feed as calves and others are started on feed as yearlings, and if the cattle are then split into two or more slaughter groups. Birth date, identification of sire and dam, breed of dam (or breed proportions in crossbred dams) should be recorded for all individuals. | |||
===Genetic Evaluation=== | ===Genetic Evaluation=== | ||
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E.g., direct, maternal, permanent environment due to dam. | E.g., direct, maternal, permanent environment due to dam. | ||
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Back fat thickness is generally included in a multiple-trait model along with its ultrasound indicator and other carcass-fat-related traits (e.g., marbling and ultrasound percentage of intramuscular fat). An early growth trait (e.g., birth or weaning weight) may also be included to account for sequential culling if the genetic covariance is sufficient. Only direct genetic effects are fitted. | |||
===Usage=== | ===Usage=== | ||
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Discuss in what circumstances the trait is an ERT or an indicator trait and how the trait should be used and not used. | Discuss in what circumstances the trait is an ERT or an indicator trait and how the trait should be used and not used. | ||
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Back fat thickness is the primary driver of [[Yield_Grade | yield grade]], the actual economically relevant trait. If EPD for both fat thickness and yield grade exist, the yield grade EPD should be used. | |||
Latest revision as of 03:03, 20 June 2024
Back fat is an estimate of external fat, which is the most important factor in determining retail yield percentage.
Phenotype
Back fat is measured at the 12th rib, perpendicular to the outside fat at a point three-fourths of the length of the ribeye muscle from the backbone. As external fat increases, the percentage of retail product decreases.
Adjusted Value
This measurement is often subjectively adjusted at the time of data collection to reflect unusual fat distribution of the carcass. The adjusted back fat thickness is then reported on an age-constant basis.
Contemporary Group
A contemporary group is a set of cattle of the same sex that have been raised together and have received equal treatment up to the point of slaughter. All progeny within a contemporary group should ideally be born within a 90-day period, and male calves must be castrated. A contemporary group up to the time of weaning will be subdivided if some cattle go on feed as calves and others are started on feed as yearlings, and if the cattle are then split into two or more slaughter groups. Birth date, identification of sire and dam, breed of dam (or breed proportions in crossbred dams) should be recorded for all individuals.
Genetic Evaluation
Back fat thickness is generally included in a multiple-trait model along with its ultrasound indicator and other carcass-fat-related traits (e.g., marbling and ultrasound percentage of intramuscular fat). An early growth trait (e.g., birth or weaning weight) may also be included to account for sequential culling if the genetic covariance is sufficient. Only direct genetic effects are fitted.
Usage
Back fat thickness is the primary driver of yield grade, the actual economically relevant trait. If EPD for both fat thickness and yield grade exist, the yield grade EPD should be used.
