Enhanced comment feature has been enabled for all readers including those not logged in. Click on the Discussion tab (top left) to add or reply to discussions.
Mature Height and Weight: Difference between revisions
(Created page with "<!-- To use this, add &preload=Template:Trait to the URL after clicking on the Create button or redlink and reload the page --> <!-- Place brief trait defin...") |
No edit summary |
||
| Line 7: | Line 7: | ||
Place brief trait definition/description here | Place brief trait definition/description here | ||
--> | --> | ||
Weight and height can be recorded on the cow when the calf is weaned. Mature cow size is useful to match [[Glossary#B | biological type]] to the environment those cows are expected to perform in. | |||
Weight and height can be recorded on the cow when the calf is weaned. Mature cow size is useful to | |||
===Phenotype=== | ===Phenotype=== | ||
| Line 14: | Line 13: | ||
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. | ||
--> | --> | ||
Mature weight should be collected on an individual animal scale and should be recorded to the nearest pound. | |||
Mature height should be measured when the cow is standing on a flat surface with her hips level. The measuring stick should be perpendicular to the ground with the height in inches measured directly over the hooks. Height can be converted to frame scores as shown [[Hip Height/Frame | here]]. | |||
Both traits should be measured on all cows every year. | |||
===Adjusted Value=== | ===Adjusted Value=== | ||
| Line 20: | Line 24: | ||
If the trait is not adjusted (e.g. Stayability) then say so | If the trait is not adjusted (e.g. Stayability) then say so | ||
--> | --> | ||
Mature weights should be adjusted for [[Body Condition Scores | body condition score]] and age, and mature heights should be adjusted for age. Young females are still growing, meaning their weight and height are expected to change over time, and adjusting for age accounts for these changes. | |||
===Contempory Group=== | ===Contempory Group=== | ||
<!-- Discuss how contemporary groups are formed --> | <!-- Discuss how contemporary groups are formed --> | ||
Because cows and calves are managed together, contemporary groups should be the same as those used for [[Weaning Weight | weaning weights]]. Contemporary groups include cows that calved around the same time, were managed together and had access to the same feed resources. | |||
Bull phenotypes are not useful for genetic evaluation because bulls are typically in very small contemporary groups. | |||
===Genetic Evaluation=== | ===Genetic Evaluation=== | ||
| Line 29: | Line 37: | ||
E.g., direct, maternal, permanent environment due to dam. | E.g., direct, maternal, permanent environment due to dam. | ||
--> | --> | ||
The model for the mature weight (or height) should include direct [[Glossary#A | additive genetic effects]] and permanent environmental effects because the traits are measured repeatedly on the same animal. The [[Glossary#G | genetic correlations]] between mature weights at different ages were greater than 0.95 (Costa et al., 2011) indicating weight can be considered as the same trait, no matter the age of the cow. | |||
===Usage=== | ===Usage=== | ||
| Line 34: | Line 43: | ||
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. | ||
--> | --> | ||
Mature weight and height provide an indication of cow feed costs as larger cows require more feed resources to maintain their body weight. Ideally, these traits should be incorporated into a [[Glossary#S | selection index]] to account for differences in cow costs in combination with other [[Economically Relevant Traits | economically relevant traits]]. | |||
Costa, R. B., I. Misztal, M. A. Elzo, J. K Bertrand, L. O. C. Silva, M. Lukaszewicz. 2011. Estimation of genetic parameters for mature weight in Angus cattle. J. Anim. Sci. 89:2680-2686. doi: 10.2527/jas.2010-3574. | |||
Revision as of 15:36, 14 May 2019
Weight and height can be recorded on the cow when the calf is weaned. Mature cow size is useful to match biological type to the environment those cows are expected to perform in.
Phenotype
Mature weight should be collected on an individual animal scale and should be recorded to the nearest pound.
Mature height should be measured when the cow is standing on a flat surface with her hips level. The measuring stick should be perpendicular to the ground with the height in inches measured directly over the hooks. Height can be converted to frame scores as shown here.
Both traits should be measured on all cows every year.
Adjusted Value
Mature weights should be adjusted for body condition score and age, and mature heights should be adjusted for age. Young females are still growing, meaning their weight and height are expected to change over time, and adjusting for age accounts for these changes.
Contempory Group
Because cows and calves are managed together, contemporary groups should be the same as those used for weaning weights. Contemporary groups include cows that calved around the same time, were managed together and had access to the same feed resources.
Bull phenotypes are not useful for genetic evaluation because bulls are typically in very small contemporary groups.
Genetic Evaluation
The model for the mature weight (or height) should include direct additive genetic effects and permanent environmental effects because the traits are measured repeatedly on the same animal. The genetic correlations between mature weights at different ages were greater than 0.95 (Costa et al., 2011) indicating weight can be considered as the same trait, no matter the age of the cow.
Usage
Mature weight and height provide an indication of cow feed costs as larger cows require more feed resources to maintain their body weight. Ideally, these traits should be incorporated into a selection index to account for differences in cow costs in combination with other economically relevant traits.
Costa, R. B., I. Misztal, M. A. Elzo, J. K Bertrand, L. O. C. Silva, M. Lukaszewicz. 2011. Estimation of genetic parameters for mature weight in Angus cattle. J. Anim. Sci. 89:2680-2686. doi: 10.2527/jas.2010-3574.
