What are these new NALF index’s and how you should evaluate cattle accordingly? It is important to remember that the TPI index is not an index for selecting replacement heifers or female selection. This index is for identifying Terminal Sires that excel in feeding perfor- mance in today’s formula and grid-based marketing of todays fed cattle environment. The North American Limousin Foundation released its Terminal Index last February which is built utilizing iGENDEC. Recently at its summer board meeting, the NALF board of directors approved an adjustment to the Terminal Profit Index which increases the emphasis on dry matter conversion rates by incorporating weaning to yearling weight spread for cattle, PWG (YW-WW) weighted by a marginal economic value of $.277). iGENDEC is a web-based tool to enable the construction of economically optimal selection indexes. iGENDEC allows for index customiza- tion through adjustment of economic and production parameters to reflect actual historical price data and made available via the Beef Improvement Federation. The new Terminal Profit Index (TPI) has been constructed to identify sires that produce the highest profit potential for fed cattle utiliz- ing traits that directly impact feeding performance and superior carcass traits. The new index was created using the most recent 10 years of USDA reported fed cattle and grid pricing data, K-State reported feedlot cattle performance and NALF data. The new TPI index models the use of Limousin sires on Angus based cows with all calves marketed on a value-based carcass grid. The units reported represent expected differences in profit per mating. The following EPD traits are included in TPI and their corresponding Marginal Economic values used in the Terminal Profit Index. HCW $1.608, REA $23.36, FAT-$162.185, MS $43.01, DMI -$20.856, CE $.957, PWG SPREAD $.277. The marginal values which are determined by parameters in the iGENDEC program and simply multiplied by each EPD trait and then added up for a total $ index value on each animal in the herdbook. The range seen on NALF’s 4500 active sires reflects a high of $210.00 and a low of -$16.00 with a mean of $94.00. NALF’S NEW TERMINAL PROFIT INDEX (TPI) & FEED CONVERSION SUB-INDEX ($G)
RELATIVE TRAIT EMPHASIS OF TRAITS USED IN TPI INDEX
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