CGs to EPDs 2006 BIF Symposium Sponsored by

CGs to EPDs 2006 BIF Symposium Sponsored by Ultrasound Guidelines Council Dr. Lisa A. Kriese-Anderson Auburn University

Would you purchase a bull ….

Would you purchase a bull …. This top young son of Superbull had a weaning weight of 636 lbs

Would you purchase a bull …. a h t i w m t c c e 5 p 3 s f o r o p e l c a n n e o fer i t p e m c u x irc e An otal c This top young son of Superbull had a r c s weaning weight of 636 lbs

So, why would you consider….

So, why would you consider…

So, why would you consider…

Ultrasound Basics n Individual ultrasound measurements (adjusted) are as useful as individual weights and measures Really only mean something within the group they came from n Ratios are better n EPDs for ultrasound or carcass are best for selection decisions n

Ultrasound Genetics Refresher n Ultrasound measurements should be taken the same time as yearling weights n Generally 320/330 to 410/430 days of age n BIF says 335 to 395 days Entire contemporary group should be measured by a certified ultrasound technician n Genetically, ultrasound measurements for carcass traits are highly correlated to actual carcass traits n n But they are not the same traits

Ultrasound Genetics Refresher Genetic Correlation Estimates Among Yearling Ultrasound and Carcass Traits UBF and BF 0. 75 to 0. 80 UREA and REA 0. 70 to 0. 75 IMF and Marbling 0. 60 to 0. 68

Ultrasound Genetics Refresher Genetic Correlation Estimates Among Yearling Ultrasound and Carcass Traits UBF and BF 0. 75 to 0. 80 UREA and REA 0. 70 to 0. 75 IMF and Marbling 0. 60 to 0. 68 Reminder – if you do not report any carcass data, individual animal accuracy can only be a high as the genetic correlation

Genetic Evaluation Begins with P=G+E

In Genetic Evaluation E ≈ Contemporary Group

Contemporary Group n A contemporary group is a group of animals with the same: Herd t Sex t Birth Season t Weigh date t Management t n The largest contemporary group is at birth. All subsequent traits are subsets of the birth contemporary group.

In Simplest Terms: n BV = h 2 x SD n SD = Selection Differential SD = (individual – avg of group)

Example Data No 6001 6002 6003 6004 6005 6006 6007 6008 6009 Sire 1 1 2 2 2 3 3 4 4 Dam 100 101 102 103 104 105 106 107 108 CG 1 1 2 2 3 WW 781 626 845 713 663 720 841 865 PW 486 522 357 482 397 532 539 562 510 REA 11. 5 11. 3 11. 2 10. 1 10. 6 12. 5 15. 1 11. 9 BF 0. 30 0. 21 0. 28 0. 17 0. 44 0. 19 0. 32 0. 31 IMF 4. 25 4. 21 4. 35 2. 89 4. 59 5. 20 3. 82 3. 90 4. 44

Data Analysis Multiple-trait animal model n WW, PWG, UREA, UBF, %IMF in analysis n Examine Sire Rankings for above traits n

Sire EPD Rankings Trait WW Milk PWG UREA UBF IMF 4 4 2 1 2 2 1 1 1 3 3 4 2 3 3 2 2 3 4

Example Data – Just 1 CG No 6001 6002 6003 6004 6005 6006 6007 6008 6009 Sire 1 1 2 2 2 3 3 4 4 Dam 100 101 102 103 104 105 106 107 108 CG 1 1 1 1 1 WW 781 626 845 713 663 720 841 865 PW 486 522 357 482 397 532 539 562 510 REA 11. 5 11. 3 11. 2 10. 1 10. 6 12. 5 15. 1 11. 9 BF 0. 30 0. 21 0. 28 0. 17 0. 44 0. 19 0. 32 0. 31 IMF 4. 25 4. 21 4. 35 2. 89 4. 59 5. 20 3. 82 3. 90 4. 44

With Wrong CG Definitions n Do not have correct comparisons in data n Sires are compared in “head to head” competition that were not n Basics of EPD analysis is to find the group average and subtract the individual measurement from it n Group mean is wrong!

Comparing Sire Ranks – Wrong CG Trait WW Milk PWG UREA UBF IMF 4 4 2 1/3 2/1 2 1/3 1/2 1 3/1 1/3 3/1 4/3 2/4 3/2 3/1 2 2/3 3/4 4/2

Not Reporting All Data No 6001 6002 6003 6004 6005 6006 6007 6008 6009 Sire 1 1 2 2 2 3 3 4 4 Dam 100 101 102 103 104 105 106 107 108 CG 1 1 2 2 3 WW 781 0 845 713 663 720 841 865 PW 486 0 357 482 397 532 539 562 510 REA 11. 5 0 11. 3 11. 2 10. 1 10. 6 12. 5 15. 1 11. 9 BF 0. 30 0 0. 28 0. 17 0. 44 0. 19 0. 32 0. 31 IMF 4. 25 0 4. 35 2. 89 4. 59 5. 20 3. 82 3. 90 4. 44

By Not Reporting All Data n If not sending in “bottom-performing” cattle, penalize the rest Group means are incorrect once again n Competition is not reported accurately n

By Not Reporting All Data Trait Mean – All data Mean-Select Data WW 753 ± 85 lbs 769 ± 75 lbs PWG 487 ± 68 lbs 483 ± 72 lbs UREA 11. 7 ± 1. 4 sq in 11. 8 ± 1. 5 sq in UBF 0. 27 ±. 09 in IMF 4. 2 ±. 63% 4. 2 ±. 67%

Sire EPD Ranks – Incomplete Data Trait WW Milk PWG UREA UBF IMF 4 4 2 1/3 2/1 1 1 1 3/1 1/3 1/2 3 3 4 2 3/2 3 2 2 3 4

Not Reporting All Data No 6001 6002 6003 6004 6005 6006 6007 6008 6009 Sire 1 1 2 2 2 3 3 4 4 Dam 100 101 102 103 104 105 106 107 108 CG 1 1 2 2 3 WW 781 0 845 713 663 720 841 865 PW 486 0 357 482 0 532 539 562 510 REA 11. 5 0 11. 3 11. 2 0 10. 6 12. 5 15. 1 11. 9 BF 0. 30 0 0. 28 0. 18 0 0. 44 0. 19 0. 32 0. 31 IMF 4. 25 0 4. 35 2. 89 0 5. 20 3. 82 3. 90 4. 44

Sire EPD Ranks – Incomplete Data Trait WW Milk PWG UREA UBF IMF 4 4 2 1/3 2/1 1 1 1/3 3/1 1/2 3 3/2 4 2 3 3 2 2/3 3/1 4

Final Comments n Actual ultrasound data needs to be treated the same as actual data from any other trait n n Must be in a comparison mode (Ratio/EPD) For use within a contemporary group May be helpful to divide data into thirds n Always remember there can be measurement error. Don’t believe in absolutes n

Field Certification Trait SEP SER Bias Corr Rump/Back Fat ≤ 0. 1 ≥ 0. 85 Ribeye Area ≤ 1. 2 ≥ 0. 80 Percent IMF ≤ 1. 2 ≤ 0. 7 ≥ 0. 70

Final Comments n Proper reporting of contemporary groups is essential n n Don’t selectively report data n n n P = G + E is the basis for all genetic evaluation Only penalizing the top animals Only hurting yourself Don’t let a trait you may not be able to visualize well keep you from doing the right thing

Additional Items n If a breed publishes both ultrasound and carcass EPD values, want ultrasound and carcass EPDs to be similar: Trait Ultrasound Carcass REA 0. 26 0. 36 REA 0. 33 -0. 04 IMF 0. 27 IMF 0. 46 0. 10 Bull 16 Bull 110

Additional Items n n If breed published just carcass and you collect/report no carcass info, accuracy will only be as high as genetic correlation Don’t single trait select!