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Linkage Mapping For Soybean (Glycine Max) Flood Tolerance, Wade Stiles Hummer

Graduate Theses and Dissertations

Flood tolerance in soybean (Glycine max) is not a well-characterized trait, yet flooding damage is second only to drought stress in terms of yield reduction. The objectives of this study were to determine genetic variation for flooding tolerance in two populations of soybean recombinant inbred lines (RILs) and to identify and confirm flood tolerant QTL. Population A (WHA) consisted of 111 RILs derived from the cross 5002T by 91210-350 and Population B (WHB) consisted of 79 RILs from the cross RA-452 by Osage. Experiments were conducted at the Rice Research and Extension Center (RREC) near Stuttgart, AR in 2015 and …

Evaluation Of Genetic And Environmental Influences On Broiler Meat Quality, Sara Katherine Orlowski

Graduate Theses and Dissertations

The effect of both genetic and environmental influences on broiler meat quality were evaluated over three experiments. Selection response was assessed for broiler lines selected for high (HBY4) and low (LBY4) four day percentage breast yield which were formed from a random bred control (RAN). A modern random bred population (MRB) created in 2015 was evaluated for differences in 4 day percentage breast yield and the resulting differences in the incidence and severity of the woody breast and white striping myopathies. Additionally, the use of embryonic thermal manipulation to impact cell division and early caloric feed restriction to slow growth …

Molecular Survey For The Honey Bee Trypanosome Parasites Crithidia Mellificae And Lotmaria Passim, Mary-Kate Williams

Graduate Theses and Dissertations

Honey bee populations have been fluctuating within recent years. No one cause has been attributed to colony fluctuations due to the theory that multiple stressors interact with one another to impact colony health. Consequently, microorganisms such as internal parasites of honey bees have been understudied as a contributor to colony health decline.

Molecular diagnostics were utilized to detect the presence of two honey bee trypanosome parasites, Crithidia mellificae and Lotmaria passim, in managed and feral honey bee populations from eight states in the United States (USA). Because studies on trypanosome infections are lacking in the USA, it is important to …

Investigation Of Bacterial Taxa As Biomarkers Of Fescue Toxicosis And Heat Stress In Grazing Beef Cows, Sarah Katherine Chewning

Graduate Theses and Dissertations

Fescue toxicosis in grazing beef cattle is caused by consumption of Ergot alkaloids associated with tall fescue (toxic fescue) and is responsible for substantial economic loss to the U.S. beef industry. Cattle consuming toxic fescue suffer adverse physiological responses, such as: hyperthermia, increased respiration rate (RR), poor reproduction and growth performance. Other adverse responses to fescue toxins include the retention of a winter hair coat and vasoconstriction in the extremities, which can lead to tissue necrosis. Identifying cattle with reduced susceptibility to fescue toxins would allow for efficient use of fescue pastures; thus, the objectives of this thesis was to: …