By Lane Geiss, ASA
$API and $TI A Bull Buyer’s Best Friends
An index is not an EPD, but rather a measure of the difference in profitability for the designed scenario. Understanding each index can help you move the profitability of your cow herd in a positive direction. Lane Giess, ASA Geneticist, answers some common questions about index selection.
Bull selection impacts a cow herd for many years, often long after the bull has left an operation. You might spend months leading up to sale season combing through catalogs, studying numbers, making phone calls, and putting in the time to make sure your selection will live up to your operation’s needs. Or, you may have a simple approach and assess bulls the day-of with your eye on a few select criteria. Either way, the bull you want is going to walk through the sale ring or across your screen, and you will have a small window of time to balance the cost of the bull and the criteria he meets (or doesn’t). Even if you have a longstanding relationship with a seedstock breeder or a buyer who picks out bulls for you, simplifying the process is beneficial.
Indices take into account many EPD and combine them into one value, expressed in dollars of profitability prediction among bulls. ASA publishes two indices: $API (All Purpose Index), and $TI (Terminal Index). $API estimates profitability when a percentage of daughters remain in the herd as replacements. $TI estimates terminal profitability. Read the full article here: bit.ly/3ZKUwvQ