Date of Graduation
5-2023
Document Type
Thesis
Degree Name
Master of Science in Animal Science (MS)
Degree Level
Graduate
Department
Animal Science
Advisor/Mentor
Littlejohn, Brittni P.
Committee Member
Powell, Jeremy G.
Second Committee Member
Looney, Charles R.
Keywords
Complete blood count; Endotoxin; Lipopolysaccharide; Prenatal programming; Toxic fescue
Abstract
The objective was to evaluate the influence of pregnant cattle grazing endophyte-infected tall, toxic, fescue (E+) during gestation on innate immune response of male offspring to an endotoxin challenge. Crossbred multiparous cows (n = 36) were bred to Red Angus sires and housed in replicated E+ or novel endophyte-infected, non-toxic, fescue (NE+) pastures prior to breeding and throughout gestation. From this calf-crop, a subset of post-weaned steers (n = 8 E+; n = 8 NE+) were selected for a lipopolysaccharide (LPS) challenge. Blood was collected every 30 min beginning 2 h prior to (Pre-LPS) and continuing 9 h following (Post-LPS) the administration of LPS (0.5 ug/kg of body weight). Cortisol and glucose were analyzed every 30 min, while complete blood count (CBC) and rectal temperature (RT) were analyzed every h during the pre- and post-LPS periods. Pre- and post-LPS hematocrit were increased in calves born to dams that grazed E+ relative to NE+ during gestation (P = 0.02; P < 0.01). Post-LPS lymphocyte counts were decreased in calves born to dams consuming E+ relative to NE+ during gestation (P = 0.01). Post-LPS eosinophil counts were increased in calves born to dams consuming E+ relative to NE+ during gestation (P = 0.05). No other variables were influenced by treatment (P > 0.05). Preliminary results of altered hematology profiles in response to an endotoxin challenge suggest an altered innate immune response of male offspring born to dams consuming E+ relative to NE+ fescue during gestation and highlight the need of ongoing research to determine corresponding cytokine profiles.
Citation
Dunkel, S. N. (2023). Influence of Pregnant Cattle Grazing Endophyte-Infected Tall Fescue on Offspring Immune Function. Graduate Theses and Dissertations Retrieved from https://scholarworks.uark.edu/etd/5010
