U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 close



Research
                Research Home
                            National Programs
                            Research Projects
                            Scientific Manuscripts
                            International Engagement
                            Scientific Software/Models
                            Databases and Datasets
                            Office of Scientific Quality Review
            Media
                News & Features
                            Multimedia
                            Briefing Room
                            Down on the Farm
                            Press Room
                            Science in Your Shopping Cart
                            Scientific Discoveries
                            Tellus
                            Under the Microscope
            About ARS
                About ARS Home
                            Staff Directory
                            Labs and Research Centers (Map)
                            Headquarter Offices
                            Organizational Chart
                            Employee Services (REE Employees Only)
                            Office of Outreach, Diversity, and Equal Opportunity
            Work With Us
                Work With Us Home
                            ARS Vacancies at USAJOBS
                            Careers at ARS Information
                            Scientific Collaborations
                            Extramural Agreements
                            1890 Faculty Research Sabbatical ProgramSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications

Title:   Author  item
                                            Vanraden, Paulitem
                                            Tooker, Melvin
  Submitted to: Book Chapter
                                    Publication Type: Proceedings
                                    Publication Acceptance Date: 4/4/2007
                                    Publication  Date: 4/4/2007
                                    Citation: Van Raden, P.M., Tooker, M.E. 2007. Genetic Evaluations Using Combined Data from All Breeds and Crossbred Cows. Book Chapter. W.E. Petersen Symposium, St. Paul, MN, April 2-3, p. 23-28. 2007.Interpretive Summary: An all-breed animal model was developed for genetic evaluations of US dairy cattle. Data from individual breeds were combined, and the combined pedigree file included 431,000 crossbred cows. Evaluations from the all- and within-breed systems were highly correlated, and most purebred breeders will not be impacted by the new model. Predicted transmitting abilities will be presented on within-breed bases for purebreds and breed-of-sire bases for crossbreds. Use of crossbred records may increase reliabilities for purebreds, and crossbreds in mixed breed herds will benefit from the use of cows of other breeds as contemporaries. Implementation is expected in May 2007.
                                Technical Abstract: An all-breed animal model was developed for routine genetic evaluations of US dairy cattle. Data sets from individual breeds were combined, and records from crossbred cows were included. About 1% of recent cows were first generation crossbreds. Numbers of cows with records since 1960 ranged from 10 to 22 million for the six traits analyzed, which were milk, fat, protein, somatic cell score, productive life, and daughter pregnancy rate.  Programs were modified to account for general heterosis, to group unknown parents separately by breed, to adjust variances separately by breed, and to adjust data to 36-month age equivalent instead of mature equivalent. Convergence rate of the all-breed model was similar to that of the previous within-breed animal model. Estimated breed differences were similar to those obtained previously from phenotypic breed means or from only the herds containing crossbred cows. Genetic evaluations from the all-breed and within-breed system had high correlations: >0.99 for recent Holsteins and slightly <0.99 for other breeds. Predicted transmitting abilities will be converted back to the within-breed bases for purebred animals and to the breed of sire base for crossbred animals so that most purebred breeders will not be impacted by the change to a multi-breed model. Crossbred animals can be evaluated accurately with the all-breed model. Reliabilities also increase for purebred relatives because of the additional crossbred records and in mixed breed herds because cows of other breeds are additional contemporaries. More research and education may be needed on using the new evaluations in design of breeding programs. Implementation is expected in May 2007.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov