UC Davis

There is a growing body of literature linking mitochondrial traits to health and performance outcomes due to their dynamic involvement in metabolism, energy production and apoptosis pathways. Despite mitochondria’s biologically active role, little research has been done exploring the effects of mitochondrial function on dairy cow performance due to the invasiveness of traditional methods utilizing liver tissues. The use of peripheral blood mononuclear cells (PBMC) offers a minimally invasive and high throughput model tissue to measure mitochondrial function in commercial dairy herds. Dairy cows face great metabolic pressure to meet the demands of rapid growth, reproduction, and lactation. A greater understanding of mitochondrial traits associated with cow performance could improve dairy farming by allowing for novel selection criteria of highly productive long-living cows. The selection and breeding of high merit cattle would improve profitability and sustainability of the industry by facilitating a reduction of cow numbers without reducing milk production and simultaneously reduce environmental impacts of dairy farming through the reduction of manure, methane, and nitrogen excretion. Therefore, the objectives of this dissertation were to determine if PBMC mitochondrial enzyme activities of citrate synthase, complex I, complex IV and complex V were 1. Different between high and low producing dairy cows 2. Associated with age, growth, reproduction, milk production and survival 3. Impacted by physiological and environmental conditions across multiple dairy farms.