Interleukin-6 and tumor necrosis factor-alpha values in elk neonates

Serological indicators of general condition would be helpful for monitoring or assessing ungulate wildlife. Toward that end, we report the Ist reference values for 2 cytokines, interleukin-6 (IL-6) and tumor necrosis factor-alpha TNF-alpha), in neonatal elk (Cervus elaphus). We obtained blood samples from 140 calves <= 6 days old in Yellowstone National Park during summer 2003-2005. IL-6 values ranged from 0 to 1.21 pg/ml with a median of 0.03 pg/ml. TNF-alpha values ranged from 0 to 225.43 pg/ml with a median of 1.85 pg/ml. IL-6 and TNF-alpha concentrations were not significant predictors of elk calf survival through 21 days. Development of ungulate-based IL-6 and TNF-alpha assays that provide greater sensitivity than cross-reacting human-based assays could be helpful in monitoring ungulate condition and health status comparisons among herds. Such information could provide indirect assessments of range quality or environmental influences among herds.