1	USDA Genetic Evaluations for Type Traits
2	Type Traits Describe physical characteristics of animal Final Score (overall assessment) Scored 50-99 Linear traits (13 traits) Scored 1-50
3	History of Type Evaluations 1986 – Sire model for final score 1988 – Collection of linear traits 1989 – Sire model for linear traits 1995 – Multi-trait animal model 2000 – Base change 2005 – Base change
4	Numbers of Appraisals of Does
5	Appraisals for Does in 2005 (n=4,593)
6	Evaluation model An equation that indicates what factors contribute to an observation Separates the genetic component from other factors Solutions used to predict the genetic potential of progeny
7	Type Evaluation Model MODEL: y = h + a + p + e y = Adjusted type record h = Herd appraisal date a = Animal genetic effect (breeding value) p = Permanent environment Non-genetic effect common to all a doe's appraisals e = Unexplained residual
8	Multi-trait Model Scores from one trait affect the evaluation of other traits through the genetic correlations
9	Genetic Correlations
10	Genetic Parameters Heritability – Portion of variation due to genetics Repeatability – Similarity of repeated records, includes genetic and permanent environmental effects
11	Heritability and Repeatability
12	Genetic Change per year from does born 1990 – 2003
13	Breeding value trend for type
14	Herds for Bucks Born 1999 – 2003 (n=2,451)
15	Daughters for Bucks Born 1999 – 2003 (n=2,451)
16	Distribution of Reliability for Final Score
17	Methods of Expressing evaluations Estimated breeding value (EBV) Animal’s own genetic value Predicted transmitting ability (PTA) ½ EBV Expected contribution to progeny
18	Combining type and production Production-Type index (PTI) Combines yield and type evaluations into a single value There are 2 versions: PTI 2:1, weights 2 production : 1 type PTI 1:2, weights 2 type : 1 production
19	AIPL web services http://aipl.arsusda.gov/query/public/tdb.shtml#GoatsTBL Queries provide display of: Pedigree information Yield records Herd test characteristics Genetic evaluations of does & bucks Yield Type Access information using: ID number Animal name Herd code
20	1918
21	1947
22	1977
23	2003
24	Summary Type data contributes to genetic evaluations of Final Score and 13 linear traits Multi-trait Animal Model combines information from all relatives and traits Few bucks have many daughters in many herds so reliability is low Production-type index combines evaluations Substantial genetic progress is occurring in several traits