Nutritional and seasonal effects on the haematology and blood chemistry in reindeer (Rangifer tarandus tarandus L.)

1. The effects of seasons and nutrition on blood were studied in 251 reindeer aged 1 day to 5 yr in Northern Finland. 2. Age influenced all blood values, except creatinine, sodium, potassium and magnesium. Serum thyroxine (T4), alkaline phosphatase, creatine phosphokinase and blood glucose in calves were high during summer and autumn indicating rapid growth, maximally 400 g/day. 3. After parturition blood haemoglobin, packed cell volume, erythrocytes, serum iron and protein values decreased while serum creatine phosphokinase, aspartate aminotransferase, lactate dehydrogenase activities and erythrocyte sedimentation rate increased. 4. All haematological values, serum proteins, lipids, minerals and blood glucose showed seasonal variations with the highest values in the autumn but the figure of serum urea concentration was opposite. 5. Changes in the serum protein concentration were associated with the serum globulins (r = 0.93, n = 251, p < 0.001).