Effects of ration, season and animal handling on composition of bison and cattle blood

Composition of ration and season of sampling markedly affected the composition of blood in six tamed bison (Bison bison) steers and eight Hereford cattle (Bos taurus) steers. Observed values extended reported ranges for albumin, phosphorus and blood urea nitrogen (BUN) in bison serum. There were several differences between species in blood composition. In particular, erythrocytic and BUN values were higher in bison than in cattle. Overall mean values for bison and cattle receiving experimental rations were, respectively: BUN, 17.1 mg/dl and 14.1 mg/dl; hemoglobin, 17.8 g/dl and 13.3 g/dl; packed cell volume (PCV), 47.6% and 35.6%; red blood cells, 9.3 x 10(6)/mm3 and 8.2 x 10(6)/mm3; mean corpuscular volume (MCV), 51.3 mean 3; mean corpuscular hemoglobin, 18.9 pg and 16.1 pg. The significant changes in blood composition associated with changes in ration composition support the use of blood composition as an index of nutritional status. There were no sex-specific differences in blood of 20 bison from Elk Island National Park and 34 bison from Wood Buffalo National Park, Alberta. Alkaline phosphatase (ALP) level was higher in juvenile than in adult bison. Impoundment of wild bison for 24 hr was accompanied by a decrease in BUN and an increase in PCV. Wild bison that were killed during handling had significantly higher blood levels of ALP, glutamate oxaloacetate transaminase, MCV and phosphorus.