Available at: https://digitalcommons.calpoly.edu/theses/129
Date of Award
MS in Agriculture - Animal Science
Dr. Bruce L. Golden
The objective of this thesis was to determine the viability of alternative genetic improvement strategies (GIS). Each alternative GIS combined the use of whole genome selection (WGS) with common reproductive methods (non-sexed semen artificial insemination (AI), sexed semen AI, embryo transfer utilizing non-sexed semen AI) that can be found on a commercial dairy operation. The viability of each GIS was determined using a discounted gene flow model, designed with parameters of a typical western dairy operation, to evaluate the following variables: reproductive method, selection intensity, accuracy of prediction and female age-class. Of the GIS investigated, a heifer-based strategy that used embryo transfer with 11% selection intensity and 85% accuracy was viable. This GIS generated 2.7 million dollars in present value of cumulative gross marginal returns. Despite such encouraging results, at the current prices for genotyping, reproductive methods and achievable prediction accuracy levels, all other GIS resulted in negative returns. Whole genome selection could be a powerful genetic improvement tool for the commercial dairy industry if high accuracy genotyping solutions and reproductive methods that allowed for high selection intensity were combined and priced less than $379.07 per individual.