UNDERSTANDING CHROMOSOMES TO MAKE GENETIC IMPROVEMENTS IN RUMINANT LIVESTOCK SPECIES

With a changing world, there is a need to produce adaptable and efficient livestock. Producers have been using selective breeding for the production of better livestock. As technologies have advanced, so has our understanding of genetics, however there is much work needed to continue improving livestock species. This work aims to create a better understanding of methods associated with making genetic improvements in ruminant livestock species. One focus area is the observation of meiotic recombination or crossovers in the spermatocytes of Beefalo, a cattle-bison hybrid, cattle, and sheep. These data show differences in crossover numbers, the positive correlation between the number of crossovers per homologous chromosome pair compared to chromosome length, location of crossovers on homologous chromosome pairs, and defects present in those chromosomes, which will provide insight into genetic predictions and hybrid mating. Another part of this thesis discusses a method to isolate the sex chromosomes in sheep to provide sequencing of the Y chromosome, which is not well characterized in ruminant livestock. These projects provide insight to the livestock industry in understanding methods for genetic improvements.masters, M.S., Animal and Veterinary Science -- University of Idaho - College of Graduate Studies, 2018-0