290 likes | 393 Views
Update on AIPL research since April 2009. What’s new!. Genomic news from the bovine g-nome. Norman. NDHIA Board – 2009 ( 2 ). News from the bovine g-nome. Calling genotypes. Genotypes called by Tad Sonstegard, BFGL, through April 2009 AIPL staff trained to run GenomeStudio
E N D
Update on AIPL research since April 2009 What’s new!
Genomic news from the bovine g-nome Norman NDHIA Board – 2009 (2)
News from the bovine g-nome Calling genotypes • Genotypes called by Tad Sonstegard, BFGL, through April 2009 • AIPL staff trained to run GenomeStudio • Cluster files shared with 4 commercial labs to allow call harmonization • Labs began providing genotypes in June
News from the bovine g-nome Commercial labs • GeneSeek (Lincoln, NE) • Genetics & IVF Institute (Fairfax, VA) • Genetic Visions (Middleton, WI) • DNA LandMarks (Saint-Jean-sur-Richelieu, QC, Canada)
News from the bovine g-nome Managing sample ID • Web query established for nominations • Indicates pedigree status • Designates nominator • Provides sample status, including rejection reasons • Query used by labs to convert sample ID to registration number and detect ID entry errors
News from the bovine g-nome Genotype database • 50,972 SNP called • Calling redone to provide additional genotypes • Many corrections required to make sample ID match • Genotypes from Illumina, University of Missouri, University of Alberta, and Switzerland also included
News from the bovine g-nome SNP selection • Call rate of >90% • Not a duplicate • Parent-progeny conflicts of <2% • Minor allele frequency of >1% • Heterozygosity within 20% of expected • For bulls, X heterozygosity of <5%
News from the bovine g-nome Evaluation preparation • Pedigree file created • Checked for missing ancestors • Pedigree requested for missing ancestors • Canadian evaluations obtained for cows • Type evaluations obtained for Holsteins
News from the bovine g-nome Genomic evaluations • Evaluations official • Holstein and Jerseys (January 2009) • Brown Swiss (August 2009) • June 2009 trait changes • Net merit calculated as sum of traits rather than as an individual trait • Holstein feet & legs and rear teat placement added • Current Interbull evaluation added at final selection-index step triannually
News from the bovine g-nome Reliability calculation • Inversion and discounting • Gain in daughter equivalents times 0.6 • Simple approximation • Could be adjusted for breed or number of close relatives • Used in April 2009 to beat deadline
News from the bovine g-nome Interbull plans • Convert genomic PTAs (August 2009) • Young bulls from France, Netherlands, and New Zealand • EU requires reliability of ≥50% for marketing • Combine using G-MACE (2010) • Proven bulls next year (2010) • Domestic and genomic evaluations computed 1–2 weeks earlier to meet Interbull deadlines • Currently genomics and MACE at same time
News from the bovine g-nome Evaluation options • National • Include cows as predictors? • Include polygenic effect in model? • International • Conversion formulas for young bulls • G-MACE to exchange genomic breeding values • Direct multicountry genomic evaluation
Culling statistics Norman NDHIA Board – 2009 (13)
Culling status report • New annual AIPL Research Report by Norman, Wright, and Lombard available at AIPL web site (September 2009) • Based on destination (4) and termination (11) codes provided by DRPCs • Separate summaries by parity and breed • 6 breeds • 2 crossbred groups • Heterosis of >90% (crossbred, CB) • Heterosis of 50 to 90% (backcross, BC)
AM-PM factors Norman NDHIA Board – 2009 (18)
Cooperative research AM-PM factors • Purdue University (Mike Schutz) • Objectives • Derive factors to estimate daily yields from 1 record for 2X milking and 1 or 2 records for 3X milking • Compare factors derived by several methods for their accuracy in predicting true daily yield or somatic cell score (SCS)
Progress to date AM-PM factors • Adjustment factors developed for Holstein and Jersey milk yield from 2X and 3X milkings • Preliminary Holstein and Jersey 2X AM-PM factors developed for fat, protein, and SCS
Plans AM-PM factors • Verification of 2X AM-PM factors for fat and protein • Development and verification of 3X factors for fat and protein • Determination of whether effect of milking interval on somatic cell count is consistent enough to allow adjustment • All breeds combined for final estimation of adjustment factors
Genetic resistance to Johne’s disease Norman NDHIA Board – 2009 (22)
Johne’s disease Cooperative studies • Characteristics of milk ELISA scores and factors affecting scores • Antel BioSystems (Byrem, Norman) • Estimation of genetic parameters and transmitting ability for milk ELISA scores • University of Minnesota (Attala ... Cole)
Johne’s disease Milk ELISA characteristics • Average score of 0.04 (±0.18) for 196,412 tests from 696 herds in 16 States from 2002 through 2008 • 3.2 and 6.1% positives based on cutoffs of 0.40 and 0.10 • Same average and SD for 42,778 scores from 25 more comprehensively tested herds in Michigan and Wisconsin • 3.0 and 5.6% positives
Johne’s disease Milk ELISA(cont.) • Cows with multiple tests within parity (10%) • 95% negative for last test if 1st test negative • 52% positive for last test if 1st test positive • Cows with multiple tests across parities (27%) • 91% negative for last test if 1st test negative • 51% positive for last test if 1st test positive
Johne’s disease Milk ELISA (cont.) • Unusually high percentage (44%) of untested cows removed from herd by end of current lactation likely indicates selection of which cows to test for Johne’s • Tested cows removed from herd • 15% of positive cows • 12% of negative cows • Further analysis needed to optimize usefulness of DHI records in evaluation of milk testing for Johne's
Johne’s disease Factors affecting scores • Cow distribution by parity • Score distribution by days from calving to test • Birth and test seasons (four 3-mo seasons starting in January) normally distributed • Score distribution by year
Johne’s disease Score factors(cont.) • Scores generally increased with year, parity, and test stage • Birth and test seasons nonsignificant • Low heritability (4%) • Moderate repeatability (26%)
Johne’s disease Correlations • 185 Holstein AI sires with ≥50 daughters • PTA correlation with breeding value for ELISA score • Milk (0.08) • Fat (–0.06) • Protein (0.03) • Selection based on SCS, productive life, DPR, and net merit could improve resistance to Johne’s • SCS (-0.01) • Productive life (–0.19) • DPR (–0.15) • Net merit (–0.16)