Alternatives for evaluating daughter performance of progeny-test bulls between official evaluations Abstr. #10

Background All artificial insemination (AI) organizations want genetic information quickly to manage their semen production operations effectively Most don’t want official information too frequently as they’re pressured to update sales material when new official information is provided

Background cont.) Receiving timely genetic information allows use of superior bulls earlier, thus increasing genetic improvement Each week of earlier delivery of sires’ Predicted Transmitting Abilities for milk is worth about $5 million annually as a result of better genetics

Background (cont.) USDA changed from quarterly to triannual genetic evaluations in August 2007 to coincide with Interbull schedule Industry cooperators had requested unofficial interim evaluations for progeny-test (PT) bulls to offset delay in receiving information

Objectives Investigate value of interim evaluations for PT bulls based on recent first-parity records of daughters and their contemporaries in cooperator herds Determine if interim evaluations provide information accurate enough for semen collection and storage (banking) for bulls of potentially superior genetic merit Secondarily assess value of interim evaluations for older bulls currently being marketed

Data Focused on Holstein PT bulls from August 2006. Extracted all the first-parity milk yield records of their daughters and their daughters’ contemporaries 4 data subsets based on recent calvings in cooperator herds Most recent 12 mo for herds with ≥5 PT daughter Most recent 18 mo for herds with ≥5 PT daughter Most recent 12 mo for herds with ≥1 PT daughters Most recent 18 mo for herds with ≥1 PT daughters

Methods Compute interim evaluations for PT bulls and sires of contemporaries (non-PT) using current USDA animal model system and 4 data subsets Calculate correlations of interim evaluations with May 2006, August 2006, and August 2007 official evaluations for bulls with ≥10 daughters for the interim evaluation and an increase in reliability

Bulls with increased reliability* AI status Calving period included No. of PT daughters in herd No. of bulls Mean daughters per bull (no.) May 2006 official August 2006 Interim Official PT 12 mo 5 695 18 39 46 1 795 21 47 18 mo 743 41 48 885 25 49 50 *May 2006 official to Aug. 2006 interim evaluation

Bulls with increased reliability* AI status Calving period included No. of PT daughters in herd No. of bulls Mean daughters per bull (no.) May 2006 official August 2006 Interim Official PT 12 mo 5 695 18 39 46 1 795 21 47 18 mo 743 41 48 885 25 49 50 Non-PT 150 58 72 318 60 76 89 190 74 413 65 81 93 *May 2006 official to Aug. 2006 interim evaluation

Correlations between evaluations* Bull AI status Calving period included No. of PT daughters in herd May 2006 official, Aug. 2006 interim Aug. 2006 interim, Aug. 2006 official May 2006 official, Aug. 2006 official PT 12 mo 5 0.78 0.95 0.86 1 0.83 0.98 0.88 18 mo 0.80 0.96 0.87 0.85 0.90 *Bulls with increased reliability from May 2006 official to Aug.2006 interim evaluation

Correlations between evaluations* Bull AI status Calving period included No. of PT daughters in herd May 2006 official, Aug. 2006 interim Aug. 2006 interim, Aug. 2006 official May 2006 official, Aug. 2006 official PT 12 mo 5 0.78 0.95 0.86 1 0.83 0.98 0.88 18 mo 0.80 0.96 0.87 0.85 0.90 Non-PT 0.82 0.92 0.93 0.94 0.89 *Bulls with increased reliability from May 2006 official to Aug.2006 interim evaluation

Evaluation reliabilities (%)* Bull AI status Change in evaluation reliability** May 2006 official Aug. 2006 interim Aug. 2006 official PT All 65 72 75 Increase 59 73 Decrease 79 71 80 Non-PT 89 82 90 77 81 83 91 *Based on most recent 18 mo of calvings in herds with 1 PT daughter **Change from May 2006 official to Aug. 2006 interim evaluation; decrease includes no change

Correlations between evaluations* Bull AI status Change in evaluation reliability** No. of bulls May 2006 official, Aug. 2006 interim Aug. 2006 interim, Aug. 2006 official May 2006 official, Aug. 2006 official PT All 1,274 0.87 0.96 0.93 Increase 885 0.85 0.98 0.90 Decrease 389 0.99 *Based on most recent 18 mo of calvings in herds with 1 PT daughter **Change from May 2006 official to Aug. 2006 interim evaluation; decrease includes no change

Correlations between evaluations* Bull AI status Change in evaluation reliability** No. of bulls May 2006 official, Aug. 2006 interim Aug. 2006 interim, Aug. 2006 official May 2006 official, Aug. 2006 official PT All 1,274 0.87 0.96 0.93 Increase 885 0.85 0.98 0.90 Decrease 389 0.99 Non-PT 2,938 0.86 0.88 413 0.89 0.95 2,525 *Based on most recent 18 mo of calvings in herds with 1 PT daughter **Change from May 2006 official to Aug. 2006 interim evaluation; decrease includes no change

Correlations with 2007 evaluation* Aug. 2006 interim official 2007 official May 2006 official 0.85 0.90 0.81 Aug. 2006 interim 0.98 0.89 Aug. 2006 official *Based on most recent 18 mo of calvings in herds with 1 PT daughter for PT bulls with increased reliability from May 2006 official to Aug. 2006 interim evaluation

Conclusions High correlations (0.95 to 0.98) between interim and official evaluations for PT bulls Highest correlation when data were from most recent 18 mo of calvings from herds with ≥1 PT daughter Higher reliability for interim evaluation than previous official evaluation for almost all PT bulls Lower reliability for almost all non-PT bulls

Impact Council on Dairy Cattle Breeding and dairy records processing centers support June, September, and November interim evaluations with release limited to PT bulls with ≥10 daughters and an increase in reliability since the most recent official evaluation

Applications Interim evaluations will provide valuable information for PT bulls between official evaluations Savings of ~$11 million/yr by eliminating delay in delivery of genetic information to US dairy producers