Mission

The mission of the Genetics and Breeding Research Unit is to discover and understand the role of genetics in beef, lamb, and pork production and quality and to develop ways to effectively use genetic variation to reduce costs and improve meat quality.

RESEARCH PROGRAM

Research at USMARC characterizes genetic differences ranging from DNA sequence differences through breed differences.  These genetic differences arise by chance in the DNA sequence, by geographic isolation, by the mating restrictions of breed associations, by crossbreeding, and by natural and human imposed selection.  Close cooperation with scientists from many disciplines results in comprehensive evaluations of genetic differences. 

Genomic scientists skilled in obtaining DNA sequence, identifying sequence differences, developing DNA markers, and determining genotypes have worked with computational biologists trained in comparison and analysis of very large collections of data to achieve significant successes.  Until recent efforts to produce whole genome sequences for cattle and pigs, much of the publicly available DNA sequence for these species was developed at USMARC.  Many QTL studies with cattle and pigs conducted worldwide use information from the linkage maps developed by USMARC and collaborators.  A genetic marker for beef tenderness is being rapidly adopted by beef cattle breeders.  Scientists are developing more markers for potential use in selection by breeders.  A Gene Atlas is being developed to identify what genes are being expressed in different tissues.  New insights into genome organization, such as microRNA elements, are gained from whole genome sequence analysis of other species and are being evaluated in livestock.  As cattle and pig genomes are sequenced, it is quickly becoming feasible to obtain tens of thousands of genotypes on a single animal.  Scientists are evaluating how this information might be used for genetic improvement.

Geneticists skilled in quantitative genetics, experimental design, and statistics develop populations of animals that are measured for traits such as growth, efficiency of production, carcass, meat quality, reproduction, and indicators of health.  Information is analyzed to estimate breed differences, heterosis, and heritabilities.  Selected populations verify whether predicted selection responses are obtained and correlated changes in other traits are measured.  Genomic scientists work with these populations to evaluate linkage and associations of traits with genetic markers.  USMARC continues to be a premier source of information on breed differences and heterosis.  In cattle, breed differences have been incorporated into across breed EPD adjustments increasing the impact of the research.  Current research is expanding to include more direct connections to prominent industry sires.  In sheep, emphasis is on easy-care maternal breeds and sire breeds for crossing.  Selection experiments in pigs and cattle have emphasized selection for reproduction.  Results have demonstrated that genetic change can be made even for traits with low heritabilities or genetic antagonisms.  Current selection experiments incorporate genetic markers into breeding decisions to evaluate their potential contributions.