Kansas State University workers used field data from the North American Limousin Foundation to determine genetic parameters for cow body condition score (BCS) and various carcass traits of progeny, including carcass wt., ribeye area (REA), fat thickness, and intramuscular fat (IMF). Following is a summary of the genetic correlations between traits.

• There were favorable correlations between carcass wt. and REA (.50), REA and fat thickness (-.19), carcass wt. and BCS (.28), and REA and BCS (.60).

• There were unfavorable correlations between IMF and carcass wt. (-.23), IMF and REA (-.40), as well as a very strong negative correlation between BCS and IMF (-.64).

• The correlation between carcass fat thickness and BCS was essentially zero (-04).

These results suggest that selection for growth and muscle would reduce IMF. Selection to increase carcass wt. and REA would increase BCS. Selection for either higher or lower BCS would not affect carcass fat thickness. Selection to increase BCS would reduce IMF. Conversely, selection for increased IMF would be expected to result in reduced BCS in cows. The latter result confirms what a number of cattlemen believe they have observed in recent years among cow herds in which there has been strong selection pressure placed on IMF. It is important to note that the results of this study apply to a specific breed population, Limousin, and may not necessarily be applicable to other populations (Eborn and Moser, 2003. Kansas State Univ. Report of Progress 908).