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NAAB Update : Base Change, Udder Health, Longevity, Fertility. Genetic Gain 1995-2000. SCS and DPR Breed Means. Udder Health Scales. Convert SCS to Udder Health?. PTA UH = -5 (PTA SCS – breed avg) Reversed scale with mean 0, SD 1 Interpreted like linear trait STA’s
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Convert SCS to Udder Health? • PTA UH = -5 (PTA SCS – breed avg) • Reversed scale with mean 0, SD 1 • Interpreted like linear trait STA’s • Positive numbers are favorable • Range similar to DPR, PL • Udder Health is term of Interbull
Longevity Trend Testing • USA Method 2 results (DYD trend) • HO bias = -.006, < limit = .035 • BS, GU bias (-.035, .032) near limit • JE, AY bias (-.072, -.089) over limit • Method 3 (data cutoff) OK for HO • Interbull rejected 5 of 15 countries
Use of MACE Longevity • Compare USA and MACE REL • MACE for single-trait (direct) PL only • AIPL then combines other trait info • Label multi-trait PL as MACE • Get foreign bull DPR from MACE PL • Better PL implies better DPR • Predict foreign DPR from PL, SCS, etc
Single vs Multi-Trait PL • Used Nov ‘01 to predict Feb ’04 PTA PL 5% benefit expected, 3% observed 547 bulls born >1995 (before vs after 1st crop daus) .1 decline in multi-trait PTA PL 3% benefit expected, 1% observed 309 bulls born 1992-94 (1st vs 2nd crop daus) .4 decline in multi-trait PTA PL • Yield correlations have been reduced • Fertility correlation now included
Cows Sold Before 1st Test • Some contribute to PL (since 2004) • Database modified to store fresh dates with 0 tests (like heifers) • 1 DRPC does not receive these, may be partial reporting (also CE?) • PL daus > milk daus for more bulls
Yield Trait Scales • Age-parity adjustments differ • 16 of 25 countries adjust to average parity • 5 adjust to mature, 4 adjust to 1st parity • Separate lactation proofs available • True protein in 5 of 21 countries: • AUS, FRA, HUN, POL, USA (as of 2000) • True% = Crude% - .19 (e.g. 3.00% vs 3.19%) • Protein yield (kg) reduced by 5-6%
Adjust Yield to Average Age? • Proposed by USDA in 1994 • Recommended by Holstein GAC, Oct 1994 • Vetoed by Council “to allow the industry time to consider the nature and effect of such a change.” • Mature EBV kg = 36 mo PTA lb • PTA lb / EBV kg = 2.2 / 2 = 1.1 • Reduced age divides by 1.1 • New Holstein base SD will multiply by 1.11 • Other breed SD increase by 1.05 to 1.18
Conformation Scales • Standardized Transmitting Ability • Mean = 0, SD = 1 • 9 of 21 countries: CHE, CZE, DNK, FRA, HUN, GBR, ITA, JPN, USA • Relative Breeding Values • Mean = 100, SD = 4, 7, 10, 12 • 8 countries in northern Europe • PTA, EBV, or other (4 countries) • Convert USA minor breeds from PTA to STA?