Project Number: 5438-31000-090-00
Project Type: Appropriated

Start Date: Aug 01, 2012
End Date: Jul 31, 2017

Objective:
Objective 1. Improve breeding and management decisions by characterizing current genetic and phenotypic variation within and between predominant beef breeds and crosses using novel genomic and genetic evaluation technologies. Objective 2. Reduce mortality and morbidity of beef cattle and sheep by identifying genetic factors affecting susceptibility to respiratory diseases and by developing effective selection programs. Subobjective 2a. Increase resistance and resilience to bovine respiratory disease complex (BRDC) through improved genetic and genomic selection tools. Subobjective 2b. Reduce the prevalence of ovine progressive pneumonia (OPP) in sheep by developing selection guidelines based on four TMEM154 haplotypes affecting susceptibility to infection. Objective 3. Enhance the competitiveness, profitability and sustainability of lamb production with reduced labor inputs by developing and evaluating an easy-care maternal line of prolific hair sheep. Objective 4. Increase effectiveness of beef cattle selection programs focused on carcass merit and reproduction by determining correlated responses in relevant traits to marker based selection.

Approach:
The overall goal is to improve genetic merit of purebred and crossbred beef cattle and sheep by enhancing knowledge of genetic variation affecting efficiency and sustainability of production. The ability to prudently exploit various genetic effects in livestock production is limited because key information is lacking. Beef cattle and sheep producers need to know how much performance differs among influential breeds based on current genetics, as well as the degree of genetic variation within breeds. Discovery and development of genetic markers affecting essential traits, determination of gene action for marker alleles, and knowledge of the net outcome of using markers are limited, yet necessary for improvement of production efficiency and product quality. These genetic effects are the foundation for improvement of breeds by selection and for development of effective purebred and crossbred mating systems. Collectively, we have designed experiments to estimate genetic differences among breeds, heterosis effects, genetic variation within breeds, and effects of genetic markers. As precise estimates of genetic effects are required for efficient implementation, we will use large experimental populations of beef cattle and sheep to collect data on a broad range of traits affecting efficiency and sustainability of life-cycle production. Experimental results will provide information as requested by beef cattle and sheep producers to help address profitability and sustainability concerns. Project scientists will provide leadership to deliver these research products to the beef cattle and sheep industries so that producers can make informed genetic and management decisions.