1 / 10

Using Days Open Early in Lactation to Allow for Earlier DPR Sire Proofs

Using Days Open Early in Lactation to Allow for Earlier DPR Sire Proofs. Melvin Kuhn, Paul VanRaden, Jana Edwards Animal Improvement Programs Laboratory Agricultural Research Service, USDA, Beltsville, MD. Reason to Project DO Records. Two sires with 10 daughters each:.

zander
Download Presentation

Using Days Open Early in Lactation to Allow for Earlier DPR Sire Proofs

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Using Days Open Early in Lactation to Allow for Earlier DPR Sire Proofs Melvin Kuhn, Paul VanRaden, Jana Edwards Animal Improvement Programs Laboratory Agricultural Research Service, USDA, Beltsville, MD

  2. Reason to Project DO Records Two sires with 10 daughters each:

  3. Reason to Project DO Records Two sires with 10 daughters each:

  4. Prediction Equation ŷ = Int + Lct + CE + ß1*Age + ß2*Age2 + ß3*Milk + ß4*Milk2 + ß5*PrevDO + ß6*PrevNS + ß7*DOx “DOx” = days open based on most recent breeding • Example: • Cow is 180 DIM and last bred at 110 days, • DOx = “DO180” = 110

  5. How Early in Lactation Can Data Be Used Compare the predictions at the various stages of lactation

  6. Means of Actual and Predicted DO

  7. Correlations of Actual DO with Predicted

  8. Correlations of Actual DO with Predicted

  9. Which Records Get Projected • If pregnancy confirmed then “y = y” otherwise y = ŷ • Probably still impose some upper limit on DOx to avoid extreme observations

  10. Summary • Predictions for DO developed and appear to work well. • As early as 90 days may be feasible  DPR proofs ~ 5 months sooner • Projected records, could be used for terminal lactations.

More Related