Accuracy (ACC)
A measure of certainty regarding the genetic merit of a bull. Accuracy values are calculated for each evaluation according to Beef Improvement Federation (BIF) Guidelines and reported as a decimal number between zero and one. Larger values indicate greater accuracy.
Active Sire
A bull that has had performance information reported on progeny born within the last two years or progeny born to a daughter calving for the first time at 33 months of age or less. B - DB - HB - NDR
B = Black DB = Double Black HB = Homozygous Black
NDR = Non-Diluted Red
Birth Weight
Expected progeny performance is reported in pounds. The EPD value predicts the difference in average birth eight of a bull's calves compared to calves of all other bulls evaluated. A positive value (+) indicates heavier-than-average birth weights while a negative value (-) indicates lighter-than-average birth weights.
Calving Ease
Heifers (H)- The ease with which a bull's calves are born to first calf heifers. A first-calf heifer is defined as a female calving for the first time at 33 months of age or less.
Cows (C)- The ease with which a bull's calves are born to mature cows. A cow is defined as a female calving for a second or subsequent time.
Expected progeny differences are reported as deviations in the percent unassisted births. When comparing calving ease EPDs of two sires, the larger EPD indicates a higher percent of unassisted births for calves sired by this bull.
Carcass Weight
The hot carcass weight of a bull's progeny. Expected progeny performance is reported in pounds and adjusted to a slaughter age of 475 days. The EPD predicts the difference in average carcass weight of a bull's progeny compared to progeny of all other bulls evaluated. A positive value indicates heavier than average carcass weights while a negative value (-) indicates high than average carcass weights.
D - P - H - S - HP
DP = Double Polled P = Polled H = Horned S = Scurred
HP = Homozygous Polled
Expected Progeny Difference (EPD)
The expected difference in performance of a bull's progeny when compared to average progeny performance of all bulls evaluated. Genetic Correlation Correlations between two traits that arise because the same genes affect both traits. When two traits are positively correlated (e.g., weaning and yearling weight), selection for an increase in one trait will result in an increase in the other trait. When two traits are negatively correlated (e.g. yearling weight and first-calving ease), selection for an increase in one
trait will result in a decrease in the other trait.
Heritability
The proportion of variation in a trait that is due to heredity and is transmitted to offspring (i.e. additive gene action). Heritability varies from zero to one. The higher the heritability of a trait, the more rapid should be the response to selection.
Marbling Score
A subjective evaluation of the amount and distribution of intramuscular fat. Degree of marbling is evaluated in the ribeye muscle between the 12th and 13th rib and is a major factor in determining USDA quality grade. Marbling scores range for 1 (devoid) to 10 (abundant). Expected progeny performance is reported in tenths of a marbling score and adjusted to a slaughter age of 475 days. The EPD value predicts the difference in average marbling score of a bull's progeny compared to progeny of all other evaluated bulls. A positive value indicates higher then average marbling scores while a negative value (-) indicates lower than
average marbling scores.
Maternal Calving Ease
Heifers (H) - The ease with which a sire's daughters calve as first-calf heifers. A first-calf heifer is defined as a female calving for the first time at 33 months of age or less.
Cows (C) - The ease with which a sire's daughters calve as mature cows. A cow is defined as a female calving for a second or subsequent time. Expected progeny differences are reported as deviations in the percent unassisted births. When comparing maternal calving ease EPDs of two sires, the larger EPD indicates a higher percent of unassisted births for calves born out of this sire's daughters.
Maternal Milk
The milking ability of a bull's daughters calves. Expected progeny performance is expressed in pounds of calving weaning weight. The EPD value predicts the difference (due to milking ability) in average 205-day weight of a bull's daughters' calves compared to calves of all other bulls evaluated. Positive values (+) indicate above-average milking ability of daughters while negative (-) values indicate below-average milking ability.
Maternal Weaning Weight
The weaning weight of a bull's daughters' calves. Expected progeny performance is reported in pounds. The EPD value predicts the difference in average 205-day weight of bull's daughters' calves compared from daughters of all other bulls evaluated. The evaluation reflects both the milking ability of the bull's daughters and the growth potential of their calves. A positive value (+) indicates heavier-than-average weaning weights while a negative value (-) indicates lighter-than-average weaning weights.
Percent Retail Cuts
An estimate of the yield of closely trimmed, boneless retail cuts from the round, loin, rib, and the chuck. Expected progeny performance is reported in percent and adjusted to a slaughter age of 475 days. The EPD predicts the difference in average carcass cutability with values greater then zero indicating higher than average percentage yield in retail cuts while a negative (-) value indicates less than average percentage yield in retail cuts.
Weaning Weight
Calf weight taken between 160 and 250 days of age and adjusted to 205 days of age and a mature dam equivalent. Expected progeny performance is reported in pounds. The EPD value predicts the difference in average 205-day weight of a bull's calves compared to calves of all other bulls evaluated. A positive value (+) indicates heavier-than-average weaning weights while a negative value (-) indicates lighter-than-average weaning weights.
Yearling Weight
Weight taken between 330 and 440 days of age and adjusted to 365 days of age and a mature dam equivalent. Expected progeny performance is reported in pounds. EPD value predicts the difference in average 365-day weight of a bull's progeny compared to progeny of all other bulls evaluated. A positive value (+) indicates heavier-than-average yearling weights while a negative value (-) indicates lighter-than-average yearling weights.
What The Carcass EPD Figures Mean In The Gateway Herd
Gateway Simmental has finished all their male calves that have not made the "Bull Pen" since 1994. Most of the calves have had a known sire and many are from a pedigreed dam. We have also evaluated our genetics on Angus cows in other test herds for a similar number of years. We have retrieved most of the carcass data through the years. Most of the calves have been sold on a grid of some kind. We have had pens grade an average of 80 plus percent "choice" down to 30 percent "choice". The back-fat range has been from .3 to .45. The average rib-eye areas on the same cattle in different years and kill facilities have varied 2 square inches and have significantly improved through the years. We have killed at all the major packing companies except Farmland and have sent several groups through Caldwell Pack at Windom, MN for PM Beef Group. I have wondered what certain carcass EPD meant in real number terms and what the differences implied in our herd based on our data. I thought some of you might be interested as well.
I would like to make a few comments on what we’ve learned. It seems that the year, feeding conditions, weather, and the size and degree of condition of the steers have a big influence on the carcass figures on a pen of cattle. For example, our steers have about .4 of back-fat at approximately 1300# live weight. Our cattle seem to make the most money if we feed them to that weight. It is very apparent that EPD’s are a more useful selection tool than trying to compare raw numbers on carcasses. With our data and what the American Simmental Association has assembled, we as Simmental producers are getting a grasp on what we are raising and how they can positively influence the beef industry. All breeds have cattle that excel in one or many of the measured traits. Raw growth is no longer as important as it used to be in this part of the country. Many producers now are commenting on how big their cows are getting.
We are at a crossroads in the breeding cattle business with COMPOSITION of growth being the driver in the future. We all want our calves to wean heavy, but at some point we must ask, what will the value of those pounds be at final harvest? Am I going to make more money by selecting more growth or am I at an optimum level already? What was the feedlot performance of my calves? At what weight did my cattle get harvested, what did they dress, quality and yield grade? How many outliers did I have? Standards, Yield Grade 4s or dark cutters. Is maturity at harvest an issue? Where do I need improvement? To improve yourself, you may need to look at the efficiency of getting to that weight, by reducing cow size or improving maternal heterosis. You may be able to adjust your calving season. There are a number of things you can do, but, at some point the added frame associated from adding more growth may be counterproductive.
In order to improve our programs and become more efficient, we need to know what our genetics do. Are we positioning ourselves to satisfy future industry demands?
There are programs like the Montana Beef Network available to producers that enable you to find out what you are producing without retaining ownership. Buyers like Dan Deichmann and Steve Christensen also are willing to help you retrieve data and help you analyze it.