RED ANGUS ONLY EPDs CARCASS WEIGHT (CW) predicts differences in hot carcass weight and is expressed in pounds. Because Red Angus’ CW EPD is a multi-trait model which includes birth, weaning and yearling weight data, the prediction is not subject to culling bias. Thus, it provides a more reliable EPD as compared to only using actual carcass weights. This computation allows for the use of weights taken on ~57,000 animals per year as compared to only ~1,500 animals per year with actual carcass weight observations. Increased Carcass Weight tends to detrimentally affect Yield Grade; the calculation of which also includes Rib Eye Area and Fat Thickness. CALVING EASE DIRECT (CED) predicts the probability of calves being born unassisted out of 2-year-old heifers. Producers want live calves born unassisted. Selecting on actual birth weight is flawed; it is influenced by non-genetic factors such as nutrition and weather (ambient temperature). While BW EPD removes these non-genetic fators, Red Angus CED has the best predictor of calving ease. The CED EPD includes variation in BW plus other influential genetic factors such as gestation length, calf shape, etc. HEIFER PREGNANCY (HPG) - predicts the probability of heifers conceiving to calve at two years of age. Many breeds offer genetic predictions of yearling bull scrotal circumference as an indicator of age of puberty. While puberty is a prerequisite, many factors influence pregnancy rate. Red Angus’ HPG EPD offers a tool which selects for what is economically relevant to ranchers — pregnant heifers. MARBLING SCORE (MARB) predicts differences for carcass marbling score as expressed in marbling score units. Higher marbling scores are positively correlated with higher carcass quality grades. MAINTENANCE ENERGY (ME) predicts differences in daughters’ maintenance energy requirements and is expressed in Mcal/Month. Recognizing that 70% of cowherd feed costs are burned up in maintaining weight and condition, Red An- gus’ ME EPD allows for the selection of bulls whose daughters will require less feed; thus, reducing cowherd expenses. Include selection pressure for ME EPD to ensure feed costs don’t get out of line when selection is made for greater performance and production. YIELD GRADE (YG) predicts differences in USDA Yield Grade score and is expressed in USDA Yield Grade units. YG EPD is calculated using the genetic predictions of CW, REA and FAT EPDs. The reliability of Red Angus’ YG EPD is enhanced by using both ultrasound and actual carcass data in the calculation of REA and FAT EPDs. Producers selecting bulls to develop profitable replacement females and maximize the value of non-replacement marketed progeny should incorporate the HERDBUILDER INDEX into their selection decisions. The HerdBuilder Index is built using the following scenario: • Red Angus bulls mated to cows and heifers • Replacement heifers retained from within the herd • All remaining progeny sold on a quality-based carcass grid Given that replacement heifers are retained, significant influence is placed on the obvious maternal ERTs of Stayability, Heifer Pregnancy and Calving Ease. Additionally, with all remaining progeny sold on a quality-based carcass grid, Marbling, Yield Grade and growth EPDs also impact the HerdBuilder Index. Use the GRIDMASTER INDEX if your operation’s primary goal is maximizing profitability of feeders in the feedyard and on the rail. The GridMaster Index is built using the following scenario: • Red Angus bulls mated to cows • All progeny sold on a quality-based carcass grid Marbling, Yield Grade and growth EPDs are the traits of primary importance in the GridMaster Index. The Profitability and Sustainability index, or ProS , is an all-purpose index that covers economically relevant traits across all aspects of the beef supply chain from conception to carcass. ProS works as a combination of the already existing HerdBuilder and GridMaster indexes, which include traits from conception to weaning, and postweaning through harvest, respectively. The ProS index is expressed in dollars per head born.
10
Made with FlippingBook - Online magazine maker