Komadan, Nieve2026-07-212026-07-212025-01https://www.suaire.sua.ac.tz/handle/20.500.14820/7806DissertationHeat stress is a growing concern to the livestock industry as temperatures continue to rise globally. Heat stress negatively impacts the productivity, health and welfare of livestock. LPS is detected in blood of heat stressed animals which contributes to systemic inflammatory response, that may compromise heat dissipation from the body during heat stress. We anticipate that animals resilient to LPS-induced stress will also be more resilient to heat stress if LPS contributes to heat stress pathology. Therefore, the purpose of this thesis was to investigate the effects of an in-vitro heat shock challenge on bovine peripheral blood monocular cells (PBMCs) isolated from high (HSR), middle (MSR), and low (LSR) stress responder dairy cows. These cows were identified as either LSR, MSR or HSR based on the peak cortisol response to an LPS challenge. Assessing PBMC function in these phenotyped animals could support future goals to genetically select cows with increased resilience to heat stress.enblood mononuclear cellsdairy cowsperipheral bloodstress phenotypedlipopolysaccharideThesis