EFFECTS OF HANDLING AND PHYSICAL RESTRAINT ON RECTAL TEMPERATURE, CORTISOL, GLUCOSE AND LEUKOCYTE COUNTS IN THE SILVER FOX (VULPES-VULPES)

The present paper describes the effects of handling and one hour of ph ysical restraint on rectal temperature (T-rec), plasma cortisol, plasm a glucose and leucocyte counts in six 8-months old silver fox vixens ( Vulpes vulpes). Mean T-rec in silver foxes 5 min after capture was 40. 1 degrees C and increased during restraint, showing a maximum of 40.8 degrees C at 30 min thereafter. Supplementary, deep body temperature ( T-b) was recorded with surgically implanted biotelemetry devices in 6 adult silver fox vixens kept isolated from environmental disturbances in a barn. Mean T in these foxes ranged between 38.0-38.4 degrees C, s howing a diurnal variation and being at the lowest between 0700-1600 h our. When a person approached a fox and was present for 5 min, T-b inc reased rapidly. The results indicated that a stress-induced hypertherm ia (SIH) was evoked rapidly within the first registration at 5 min aft er capture, and that this response continued during one hour of physic al restraint. Plasma glucose and plasma cortisol levels increased duri ng one hour of physical restraint, whereas numbers of lymphocytes, tot al white blood cell counts, and total granulocytes decreased. Furtherm ore, previously reported base levels of plasma cortisol and plasma glu cose were exceeded. The results indicate that the hypothalamic-pituita ry-adrenal (HPA) axis and the sympathoadrenal medullary (SAM) system w ere activated within 5 min of handling and restraint. Furthermore, hyp erthermia is a promising indicator of acute stress in silver foxes.