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Outline

1	Effectiveness of genetic evaluations in predicting daughter performance in individual herds
2	Background Response to genetic selection has been well documented on a population basis Dairy producers are more likely to appreciate its value if it is demonstrated in their own herd Prediction on an individual herd level should be a useful extension tool
3	Data First lactation cows calving from 2005-2008 Required to have both sire and dam PTAs Matched cow’s phenotypic record with sire and dam PTA from evaluation prior to cow’s first calving Herds with a minimum of 50 cows meeting above criteria 7,697 Holstein herds; 412 Jersey herds
4	Prediction model – ran for each herd Phenotypic trait= Parent Average of same trait + cow’s calving yr + Error
5	Traits predicted: 1^st lactation ME Milk 1^st lactation ME Fat 1^st lactation ME Protein 1^st lactation ME SCS Days open (using PTA DPR * -4) Productive life (PL)
6	Individual herd regression (b) - Holstein Trait Mean and SD of b 1^st lactation ME Milk 1.01 ± 0.45 1^st lactation ME Fat 0.90 ± 0.44 1^st lactation ME Protein 0.81 ± 0.43 1^st lactation ME SCS 0.88 ± 0.60 1^st lactation Days open 1.03 ± 1.10 Productive Life 0.71 ± 0.69
7	Individual herd regression (b) - Jersey Trait Mean and SD of b 1^st lactation ME Milk 1.02 ± 0.42 1^st lactation ME Fat 0.91 ± 0.39 1^st lactation ME Protein 0.91 ± 0.43 1^st lactation ME SCS 0.86 ± 0.69 1^st lactation Days open 1.03 ± 1.12 Productive Life 0.69 ± 0.80
8	Distribution of regressions (b) - Holstein
9	Distribution of regressions (b) - Jersey
10	Why herds might show different progress than expected Too few records to show an accurate picture Different management level Misidentification Predicting 1^st lactation phenotypes, based on PA calculated from lactations 1-5
11	Mean regressions (b) from predicting 1^st lactation traits from PA by number of cows - Holstein
12	Standard deviations of the regressions (b) from predicting 1^st lactation traits from PA by number of cows - Holstein
13	Mean regressions (b) from predicting 1^st lactation traits from PA by number of cows - Jersey
14	Standard deviations of the regressions (b) from predicting 1^st lactation traits from PA by number of cows - Jersey
15	Mean regressions (b) from predicting 1^st lactation traits from PA by production level - Holstein
16	Standard deviations of the regressions (b) from predicting 1^st lactation traits from PA by production level - Holstein
17	Mean regressions (b) from predicting 1^st lactation traits from PA by production level - Jersey
18	Standard deviations of the regressions (b) from predicting 1^st lactation traits from PA by production level - Jersey
19	Conclusions
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