Behavior Genetics Studies Using the Canadian Beef Reference Herd
a brief summary about behavior research and associated growth and carcass characteristics
This webpage was posted on December 2, 2001 by Sheila Schmutz schmutz@sask.usask.ca
| Behavior was an important trait for early domestication. Many ranchers still consider behavior a trait used to cull animals from their herd for the safety of themselves as well as the other cattle. Although most ranchers will tolerate some agression near calving, even then too much agressive behavior results in a trip to the slaughterhouse for the cow and her calf at weaning time. |
Dr. Joe Stookey and his students used the Canadian Beef Reference Herd of 17 embryo transfer calf families to study behavior. They used a Motion Measurement Device and which was an adaptation on an electronic weigh cage to record the amount and degree of movement of each animal during a one minute period. The initial measurement was done the day of weaning and we term it "temperament" here. This procedure was repeated at bi-monthly intervals and the difference between the initial and third measurement, we term habituation. This is because the animals that adjust to handling "habituate" and are usually acceptable in a ranch setting, whereas some animals become more agitated the more they are handled.
In order to benefit by selection, a trait must be heritable. Comparison of the temperament scores and habituation scores among the full siblings in the ET families allowed us to calculate heritability. The heritability of temperament was 0.36 and of habituation was 0.46. Therefore both of these traits are of moderate to high heritability and selection should be effective.
QTL Mapping of Behavior Traits
QTL= quantitative trait locus or gene. This abbreviation is typically used to indicate the region of a chromosome where a statistically significant peak was found showing close association or linkage between a marker or gene and a trait. One such "peak" was found on cattle chromosome 14. The corresponding known gene under this peak is thyroglobulin. This gene was mapped onto chromosome 14 using a technique called in situ hybridization by Jim Womack's group. A former graduate student, Tim Daskalchuk, developed a PCR-RFLP test or SNP test to map this gene onto the linkage map of chromosome 14 amongst microsatellite markers.
More recently the use of a polymorphism in thyroglobulin has been patented as the GeneStar® test by Genetic Solutions of Australia. They suggest one allele occurs more often in marbled beef.
| Behavior Trait | Growth Trait | Correlation | Significance |
|---|---|---|---|
| Temperament | Adjusted Yearling Weight | r=0.27 | P=0.0001 |
| Habituation | Adjusted Yearling Weight | r=0.209 | P=0.02 |
Associations to Carcass Traits
Although we associate a particular physique with energetic, outdoorsy people and another with the "couch potato" type, this is not usually done with cattle. Our preliminary data would suggest there may be a correlation to the amount of fat cattle develop, relative to their temperament. Such a correlation does not extend to marbling fat or to shear force measurements of meat tenderness, however.
Association to Temperament Score
| Carcass Trait | Correlation | Significance |
|---|---|---|
| Grade Fat | r=0.276 | P=0.002 |
| %Lean | r=0.198 | P=0.026 |
| Marbling | r=0.55 | P=0.54 |
| Shear Force | r=0.019 | P=0.84 |
Other Related Cattle Websites
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for further information contact:
Department of Animal and Poultry Science
University of Saskatchewan
Saskatoon, Canada S7N 5A8
phone: (306)966-4153 fax: (306)966-4151
e-mail
schmutz@sask.usask.ca