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VIRGINIA ANGUS Magazine
EPDs: The Unintended Consequences
By Bobby Grove
Expected Progeny Differences (EPDs) are a great tool and cattle breeders have made great advances in the traits that EPDs measure. For example, EPDs are largely responsible for the simultaneous selection improvement in the negatively correlated traits of birth weight and yearling weight. However, many breeders have observed that functional traits—which are not measured by EPDs and are antagonistic to growth and carcass traits—have suffered as growth and carcass traits have improved. These cow-making functional traits include, but are not limited to, structural soundness, fertility, fleshing ability, calf survivability, longevity, udder quality, and disposition. Strength in these traits made the Angus breed the maternal breed of choice in the beef industry. Unfortunately, the indiscriminate use of EPDs has led to the unintended consequences of losing functional traits. This is due to the lack of selection emphasis for these traits, the genetic antagonisms between functional traits and current EPD traits, and other problems associated with carcass EPDs. These problems—and the fact that current EPDs only measure revenue traits—highlight the need for production cost based EPDs like cow maintenance costs, stayability, fertility, etc. (The Red Angus breed is currently publishing production cost based EPDs). Instead of developing production cost based EPDs, the Angus breed developed superfluous and potentially misleading $Value EPDs. Having revenue based EPDs without cost based EPDs is like considering the purchase of a car based on performance (acceleration and handling) without knowing the costs of operation (gas mileage, reliability, repair costs, etc.).
Loss of Functional Traits
It is important to remember that in spite of the advances in technology the last 30 years—AI, ET, EPDs, cloning, etc.—the cow calf producer has never done better than in the early 1970s when 1000-1100 pound Angus cows weaned 700 pound Charolais sired calves. These results represent the model of cow/calf production efficiency. Obviously, for technology to improve on this efficiency, it must be used properly for bottom line advances to be realized. That's why advancement of revenue based EPDs without concurrent selection discipline for functional traits can result in an increase in production costs that exceed value added revenue from better EPDs. Breeding by paper has led to a loss of economically important functional and production cost based traits, traits that are not measured by EPDs.
Some would argue that breeding by paper has prevented breeders from developing the skills needed to visually evaluate cattle for functional traits. For example, at a recent "EPD Factory" sale, the four featured donor cows had the following combined problems with their feet: long toes, corkscrew toes, corns, and vertical cracks to the hairline. There are no EPDs that measure these economically important structural faults. And if breeders are unable to notice glaring problems with a cow's feet, how can they evaluate more subtle differences in skeletal design?
The most profitable commercial breeder I know does not feed his cows in the winter. They graze stockpiled fescue. He has no expenses for hay, hay making equipment, feeding equipment, or labor. He knows the value in the ability of cows to flesh and function on grass. Yet, in today's world of EPD antagonisms, the term "grass cattle" often means lower demand cattle that lack breed leading EPDs. Cost based EPDs would be more valuable to this breeder than revenue based EPDs, yet the American Angus Association does not provide this information to its membership.
Considerable discussion was devoted to environmental adaptability at the recent BIF meetings. Progressive breeders are once again recognizing that the ability of a cow to fit her environment in a low cost manner is a nonnegotiable prerequisite for rancher profitability. Fortunately, we have an EPD that is helpful in achieving this goal. The hip height EPD, often ignored, is the most valuable EPD tool breeders currently have to predict environmental adaptability. Because these EPDs help predict maturity patterns and mature size, breeders will find that a given hip height EPD--specific for their individual environment—will help predict environmental adaptability. Cattle with hip height EPDs at or below that threshold score will be more likely to work efficiently in that environment, whereas hip height EPDs above that level will be less likely to adapt.
The Complicated Carcass Conundrum
The October 1999 issue of the Angus Journal contains an article by Ron Bolze, "Beyond Genetics" in which he correctly states, "Perhaps the answer to the antagonistic nature of quality grade vs. yield grade vs. maternal function lies in the identification and propagation of those lines that can routinely: (1) marble sufficiently…at a reasonable fat cover… (2) produce above breed-average muscling per unit of carcass weight; and (3) produce easy fleshing, functionally adapted daughters for a given environment."
This statement fits nicely with university research that shows that cow production efficiency is more important than growth and that growth is more important than carcass traits. Yet, the success of CAB has dramatically increased the demand for Angus bulls. On the other hand, selection for increased marbling for CAB acceptance has stimulated a mindless race to create Wagyu-like Angus with not only abundant marbling, but also lower fertility, less muscle, less fleshing ability, and poorer environmental adaptability, resulting in significantly higher production costs. One real world example concerns two neighboring Angus breeders, one who has bred for four generations for higher marbling, and one who has maintained traditional selection for balanced traits. Wintering costs are $200/cow higher for the high marbling neighbor, while the balanced trait neighbor's cows stay in better flesh, have a higher pregnancy rate, and even wean heavier calves. Additionally, research at the University of Florida on single trait selection for marbling revealed a significant reduction in fertility in the high marbling cattle. Fertility is still the single most important trait for cow-calf producer profitability.
Have we created an economic bubble with selection for marbling similar to when the technology driven NASDAQ was at 5000? NASDAQ 5000 was driven by the belief that demand for bandwidth was doubling every six months. The technology bubble burst when that statement was proven to be wrong, and the NASDAQ fell to 1300, a 74% decrease in valuation. Likewise, our marbling bubble is built on the belief that increasing end product value will increase profits. As discussed earlier, profits and revenue are two different things. While we should not lose marbling, we must also understand that there is nothing wrong with breed average marbling. Marbling should be increased only after maintaining muscling and functional traits.
Likewise, concern exists when using current EPDs for ribeye area (REA) evaluation. Angus breeders agree that as a breed, we need more muscle, and EPDs show that REA is increasing. Yet, when slaughter data is analyzed, REA is actually being lost in the Angus breed. How can the EPD for REA be increasing while actual REA in relation to carcass weight is decreasing year after year? It is because carcass EPDs are based on an age constant endpoint. This means that increases in REA EPD only mean that REA is increasing at a given age. In the real world, yield grade scores are influenced by REA per unit of carcass weight. In relative terms, the age constant endpoint has resulted in REA increasing at a slower rate than carcass weight. The bottom line is that REA/unit of carcass weight is continually decreasing, meaning real muscle is being lost.
The current use of the fat thickness (FT) EPD is another area of concern. Breeders select for negative FT EPDs, thinking it will result in leaner cattle at slaughter. Fat thickness at slaughter is primarily a management issue—cattle are fed until the feedlot management determines it is the best time for harvest. The FT EPD is irrelevant because the cattle are fed until they reach the desired actual FT level. Because early maturing cattle deposit fat more readily than late maturing cattle, the long trem results of selecting for negative FT EPDs generally are bigger framed, higher maintenance cows. The combination of selection for high marbling and negative fat thickness EPDs, coupled with REA selection based on an age constant endpoint has resulted in bigger framed, later maturing, harder fleshing and lighter muscled cattle both in the feedlot and in production. Fertility and maternal function—traditional strengths of the Angus breed—are being lost. Resulting increases in production costs are greater than the increases in end product value, as would be expected when mature size increases while muscle and maternal function are being lost.
Problems encountered with FT and REA EPDs can be readily solved by switching from an age constant endpoint to a fat constant or weight constant endpoint. Problems with extreme selection pressure for marbling can be solved by the creation of a high demand end product that does not place as much emphasis on marbling as traditional CAB. Copious research has proven that there is a positive relationship between tenderness and retail value and that quality grades do not adequately predict tenderness. Furthermore, research has shown that age at harvest (calf feds are more tender than yearling feds) and carcass aging provide better predictors of tenderness. A guaranteed tender, value added High Select and Low Choice CAB product, based on harvesting young cattle (15 months and younger) combined with aging carcasses 14 days would dramatically increase the number of total cattle qualifying for a premium branded program, increase revenue to the American Angus Association and to producers, and reduce the selection pressure for marbling. It should also be noted that at this writing, the Choice/Select price spread has narrowed to $1/cwt. Health conscious consumers and followers of the popular Atkins diet also demand leaner beef cuts, creating a tremendous opportunity for a guaranteed lean and tender branded CAB product.
Conclusion
In the song "So Sorry Blues", Texas singer/songwriter Robert Earl Keen laments, "I've been in this rut so long, I believe I've found my groove". EPDs may have led some breeders into a rut of unintended consequences, but they can also help breeders find a profitable groove for future mating decisions. Breeders simply need to use existing EPDs in concert with production costs and functional traits to produce cattle with long term genetic merit. To help breeders focus on production costs, whole herd reporting and cost based EPDs need immediate implementation, along with a reevaluation of carcass EPDs. A cow maintenance cost EPD could be rapidly developed from existing data quantifying frame size, milk production, and fat thickness. But, even when cost based EPDs are developed, breeders still need not rely solely on the numbers. The Angus cow made the Angus breed great. Traditional Angus values evolved without EPDs in the past, and traditional selection values need to be practiced to keep the Angus cow the number one choice of commercial breeders nationwide.
EPDs: The Unintended Consequences
By Bobby Grove
Expected Progeny Differences (EPDs) are a great tool and cattle breeders have made great advances in the traits that EPDs measure. For example, EPDs are largely responsible for the simultaneous selection improvement in the negatively correlated traits of birth weight and yearling weight. However, many breeders have observed that functional traits—which are not measured by EPDs and are antagonistic to growth and carcass traits—have suffered as growth and carcass traits have improved. These cow-making functional traits include, but are not limited to, structural soundness, fertility, fleshing ability, calf survivability, longevity, udder quality, and disposition. Strength in these traits made the Angus breed the maternal breed of choice in the beef industry. Unfortunately, the indiscriminate use of EPDs has led to the unintended consequences of losing functional traits. This is due to the lack of selection emphasis for these traits, the genetic antagonisms between functional traits and current EPD traits, and other problems associated with carcass EPDs. These problems—and the fact that current EPDs only measure revenue traits—highlight the need for production cost based EPDs like cow maintenance costs, stayability, fertility, etc. (The Red Angus breed is currently publishing production cost based EPDs). Instead of developing production cost based EPDs, the Angus breed developed superfluous and potentially misleading $Value EPDs. Having revenue based EPDs without cost based EPDs is like considering the purchase of a car based on performance (acceleration and handling) without knowing the costs of operation (gas mileage, reliability, repair costs, etc.).
Loss of Functional Traits
It is important to remember that in spite of the advances in technology the last 30 years—AI, ET, EPDs, cloning, etc.—the cow calf producer has never done better than in the early 1970s when 1000-1100 pound Angus cows weaned 700 pound Charolais sired calves. These results represent the model of cow/calf production efficiency. Obviously, for technology to improve on this efficiency, it must be used properly for bottom line advances to be realized. That's why advancement of revenue based EPDs without concurrent selection discipline for functional traits can result in an increase in production costs that exceed value added revenue from better EPDs. Breeding by paper has led to a loss of economically important functional and production cost based traits, traits that are not measured by EPDs.
Some would argue that breeding by paper has prevented breeders from developing the skills needed to visually evaluate cattle for functional traits. For example, at a recent "EPD Factory" sale, the four featured donor cows had the following combined problems with their feet: long toes, corkscrew toes, corns, and vertical cracks to the hairline. There are no EPDs that measure these economically important structural faults. And if breeders are unable to notice glaring problems with a cow's feet, how can they evaluate more subtle differences in skeletal design?
The most profitable commercial breeder I know does not feed his cows in the winter. They graze stockpiled fescue. He has no expenses for hay, hay making equipment, feeding equipment, or labor. He knows the value in the ability of cows to flesh and function on grass. Yet, in today's world of EPD antagonisms, the term "grass cattle" often means lower demand cattle that lack breed leading EPDs. Cost based EPDs would be more valuable to this breeder than revenue based EPDs, yet the American Angus Association does not provide this information to its membership.
Considerable discussion was devoted to environmental adaptability at the recent BIF meetings. Progressive breeders are once again recognizing that the ability of a cow to fit her environment in a low cost manner is a nonnegotiable prerequisite for rancher profitability. Fortunately, we have an EPD that is helpful in achieving this goal. The hip height EPD, often ignored, is the most valuable EPD tool breeders currently have to predict environmental adaptability. Because these EPDs help predict maturity patterns and mature size, breeders will find that a given hip height EPD--specific for their individual environment—will help predict environmental adaptability. Cattle with hip height EPDs at or below that threshold score will be more likely to work efficiently in that environment, whereas hip height EPDs above that level will be less likely to adapt.
The Complicated Carcass Conundrum
The October 1999 issue of the Angus Journal contains an article by Ron Bolze, "Beyond Genetics" in which he correctly states, "Perhaps the answer to the antagonistic nature of quality grade vs. yield grade vs. maternal function lies in the identification and propagation of those lines that can routinely: (1) marble sufficiently…at a reasonable fat cover… (2) produce above breed-average muscling per unit of carcass weight; and (3) produce easy fleshing, functionally adapted daughters for a given environment."
This statement fits nicely with university research that shows that cow production efficiency is more important than growth and that growth is more important than carcass traits. Yet, the success of CAB has dramatically increased the demand for Angus bulls. On the other hand, selection for increased marbling for CAB acceptance has stimulated a mindless race to create Wagyu-like Angus with not only abundant marbling, but also lower fertility, less muscle, less fleshing ability, and poorer environmental adaptability, resulting in significantly higher production costs. One real world example concerns two neighboring Angus breeders, one who has bred for four generations for higher marbling, and one who has maintained traditional selection for balanced traits. Wintering costs are $200/cow higher for the high marbling neighbor, while the balanced trait neighbor's cows stay in better flesh, have a higher pregnancy rate, and even wean heavier calves. Additionally, research at the University of Florida on single trait selection for marbling revealed a significant reduction in fertility in the high marbling cattle. Fertility is still the single most important trait for cow-calf producer profitability.
Have we created an economic bubble with selection for marbling similar to when the technology driven NASDAQ was at 5000? NASDAQ 5000 was driven by the belief that demand for bandwidth was doubling every six months. The technology bubble burst when that statement was proven to be wrong, and the NASDAQ fell to 1300, a 74% decrease in valuation. Likewise, our marbling bubble is built on the belief that increasing end product value will increase profits. As discussed earlier, profits and revenue are two different things. While we should not lose marbling, we must also understand that there is nothing wrong with breed average marbling. Marbling should be increased only after maintaining muscling and functional traits.
Likewise, concern exists when using current EPDs for ribeye area (REA) evaluation. Angus breeders agree that as a breed, we need more muscle, and EPDs show that REA is increasing. Yet, when slaughter data is analyzed, REA is actually being lost in the Angus breed. How can the EPD for REA be increasing while actual REA in relation to carcass weight is decreasing year after year? It is because carcass EPDs are based on an age constant endpoint. This means that increases in REA EPD only mean that REA is increasing at a given age. In the real world, yield grade scores are influenced by REA per unit of carcass weight. In relative terms, the age constant endpoint has resulted in REA increasing at a slower rate than carcass weight. The bottom line is that REA/unit of carcass weight is continually decreasing, meaning real muscle is being lost.
The current use of the fat thickness (FT) EPD is another area of concern. Breeders select for negative FT EPDs, thinking it will result in leaner cattle at slaughter. Fat thickness at slaughter is primarily a management issue—cattle are fed until the feedlot management determines it is the best time for harvest. The FT EPD is irrelevant because the cattle are fed until they reach the desired actual FT level. Because early maturing cattle deposit fat more readily than late maturing cattle, the long trem results of selecting for negative FT EPDs generally are bigger framed, higher maintenance cows. The combination of selection for high marbling and negative fat thickness EPDs, coupled with REA selection based on an age constant endpoint has resulted in bigger framed, later maturing, harder fleshing and lighter muscled cattle both in the feedlot and in production. Fertility and maternal function—traditional strengths of the Angus breed—are being lost. Resulting increases in production costs are greater than the increases in end product value, as would be expected when mature size increases while muscle and maternal function are being lost.
Problems encountered with FT and REA EPDs can be readily solved by switching from an age constant endpoint to a fat constant or weight constant endpoint. Problems with extreme selection pressure for marbling can be solved by the creation of a high demand end product that does not place as much emphasis on marbling as traditional CAB. Copious research has proven that there is a positive relationship between tenderness and retail value and that quality grades do not adequately predict tenderness. Furthermore, research has shown that age at harvest (calf feds are more tender than yearling feds) and carcass aging provide better predictors of tenderness. A guaranteed tender, value added High Select and Low Choice CAB product, based on harvesting young cattle (15 months and younger) combined with aging carcasses 14 days would dramatically increase the number of total cattle qualifying for a premium branded program, increase revenue to the American Angus Association and to producers, and reduce the selection pressure for marbling. It should also be noted that at this writing, the Choice/Select price spread has narrowed to $1/cwt. Health conscious consumers and followers of the popular Atkins diet also demand leaner beef cuts, creating a tremendous opportunity for a guaranteed lean and tender branded CAB product.
Conclusion
In the song "So Sorry Blues", Texas singer/songwriter Robert Earl Keen laments, "I've been in this rut so long, I believe I've found my groove". EPDs may have led some breeders into a rut of unintended consequences, but they can also help breeders find a profitable groove for future mating decisions. Breeders simply need to use existing EPDs in concert with production costs and functional traits to produce cattle with long term genetic merit. To help breeders focus on production costs, whole herd reporting and cost based EPDs need immediate implementation, along with a reevaluation of carcass EPDs. A cow maintenance cost EPD could be rapidly developed from existing data quantifying frame size, milk production, and fat thickness. But, even when cost based EPDs are developed, breeders still need not rely solely on the numbers. The Angus cow made the Angus breed great. Traditional Angus values evolved without EPDs in the past, and traditional selection values need to be practiced to keep the Angus cow the number one choice of commercial breeders nationwide.
