ASA Releases DMI and $Gain - Frequently Asked Questions
Frequently Asked Questions
The American Simmental Association has officially released the $Gain economic subindex, as well as the Dry Matter Intake (DMI) Expected Progeny Difference (EPD) in an alpha release format on Herdbook. The purpose of these traits is to help breeders better characterize terminal performance by evaluating genetic differences for feed intake and the profitability potential associated with growth relative to intake.
One of the more recent concerns in the business has been related to feed “efficiency” in feeder cattle. The reason for the quotes around “efficiency” is that in many cases, the tools developed to address feed conversion have been related to biological efficiency rather than economic efficiency, which can sometimes be antagonistic to meaningful improvement. A solution to this is the $Gain economic subindex developed by International Genetic Solutions to more appropriately address selection for improved feedlot performance by optimizing the economic efficiency during the finishing phase. Unlike traditional single-trait selection for dry matter intake (DMI) or residual feed intake (RFI), $Gain balances both the economic component of average daily gain (ADG) and DMI, ensuring that the most profitable animals are identified. The result of $Gain is already factored into both $API and $TI, meaning we already factor the relationship of value of gain to the cost of intake in both indexes.
The $Gain prediction is expressed as the difference in daily profitability of animals in the feedlot based on their combination of DMI and ADG expected progeny differences (EPD). ADG is positively weighted by the value of a pound of gain, and DMI is negatively weighted by the cost of a pound of dry matter.
ASA Geneticist Lane Giess answered the most common questions ASA has received since the release of DMI and $Gain:
How are DMI and $Gain factored into $API and $TI?
Giess: The relationship of the value of gain against the cost of intake is, and has already been, factored into $API and $TI since their inception. Because of the high genetic correlation between growth and intake, a pseudo-prediction for intake was developed using growth phenotypes and integrated into the indexes in the same structure as the $Gain prediction. This pseudo-prediction for intake does not, however, incorporate actual feed intake records, thus the development and subsequent release of DMI. Development is still underway to migrate the new DMI EPD into the calculation of $API and $TI.
Why are the DMI and $Gain predictions only updated monthly?
Giess: Currently, the DMI and $Gain evaluation is performed monthly. Development is still underway to integrate the DMI and $Gain evaluation into the weekly IGS multi-breed genetic evaluation. For this reason and until full integration with IGS, the evaluation is initiated at the start of every month with predictions published shortly after.
What should I consider when factoring DMI into my decision making?
Giess: Producers should exercise caution when making genetic selections based solely on DMI reduction. Studies have shown there is a high genetic correlation between DMI and Average Daily Gain (ADG), meaning that sole selection for reduced intake can inadvertently lead to slower-growing, smaller-framed cattle. Selection on biological efficiency does not always equate to profitability, thus the recommendation for considering $Gain in your selection decisions.
If you have more questions about evaluating and utilizing DMI and $Gain please contact the ASA office at 406-587-4531.