Project Number: 1265-31000-081-00
Project Type: Appropriated

Start Date: Jul 24, 2002
End Date: Jul 23, 2007

Objective:
Objective 1: Previously identified QTL will be characterized in extended pedigrees of families segregating different QTL alleles to better resolve the genetic location of the QTL. Expanded analysis will include QTL affecting protein percentage on bovine chromosome 6 and dairy form on chromosome 27. Objective 2: Once QTL-containing intervals are better resolved, high-resolution comparative and BAC contig maps of these genetic intervals will be developed to identify positional candidate genes that may be responsible for these putative effects. Markers developed in Objective 2 will also be used to improve the QTL refinement conducted in Objective 1. Objective 3: Dairy cattle families having unique or extreme phenotypes will be identified, acquired, and studied to detect new and validate previously identified QTL of economic importance. These studies will focus on detecting QTL affecting fertility, calving ease, milk production, conformation and health traits. Objective 4: Appropriate statistical tools needed to analyze complex dairy pedigrees will be identified and applied. In addition, bioinformatics tools will be developed to automate data processing in support of QTL detection and mapping methods.

Approach:
Traditional methods of genetic selection have greatly improved milk production, but have difficulty improving lowly heritable traits like reproduction and disease resistance. Lack of selection for these economically important traits has a huge impact on global competitiveness and the sustainability of producers and the entire dairy industry. The long-term goals of this project are to identify DNA markers associated with economically important traits that can be applied in marker-assisted selection programs and to identify and characterize the genes responsible for the observed effects. We propose to accomplish these long-term goals through the following objectives: 1) fine-map and characterize previously identified quantitative trait loci (QTL); 2) develop high-resolution comparative and BAC contig maps of regions containing QTL; 3) identify new and validate previously identified QTL affecting reproduction, milk production, conformation and health traits from novel resource populations and 4) identify and adapt appropriate statistical tools for analysis of complex dairy pedigrees and develop bioinformatics tools to automate data processing in support of QTL detection and mapping methods. Research accomplished during this project will result in greater genetic improvement through marker-assisted selection and development of new and improved bioinformatic tools and statistical analysis methods. The research findings will enable dairy producers to overcome the financial impact of disease through reduced utilization of antibiotics and veterinary treatments, increased protein yield and improved fertility.

Project Team

Sonstegard, Tad Van Tassell, Curtis - Curt Connor, Erin

Project Annual Reports

FY 2003

Related National Programs

Food Animal Production (101)

Related Projects

A Functional Genomics Approach to Define Relationships Between Stress & Immunity in Cattle    Validation of Parasite Indicator Qtl for Cattle in a Sheep Resource Population