Remote blood collection in reindeer (Rangifer tarandus tarandus L): a preliminary study

Effect of method of blood sample collection on adrenal activity in farmed red deer and sheep following administration of ACTH

The effect of method of blood sample collection (automatic blood sampling equipment (ABSE) v. manual) on cortisol and progesterone concentrations was investigated in 20 farmed red deer hinds and 20 domestic sheep ewes following dexamethasone and exogenous ACTH administration. Ten animals were subjected to either automatic sampling or manual sampling via jugular venipuncture in 1 week, with the treatment groups reversed in the 2nd week. The ABSE was programmed to collect a blood sample, then deliver 2 mg dexamethasone, collect a further blood sample 120 min later and then inject 100 fig ACTH. Thereafter, samples were collected at 15-min intervals during a 2·5 h period (12 samples in total). In the manual injection and sampling treatment, four samples were collected: (1) before dexamethasone administration, (2) before ACTH administration, (3) 60 min after ACTH administration, and (4) 150 min after ACTH administration. The success rate of blood sampling with ABSE was 80%. The overall mean packed cell volume (PCV) from samples collected by ABSE from both hinds and ewes was significantly lower than that from samples collected manually (P < 0·01) and PCV declined with time in manually sampled animals (P < 0·01). Plasma cortisol concentrations peaked at 45 min after ACTH administration in sheep and deer. In sheep, there was a marked fluctuation in the plasma cortisol concentrations with time. Both deer and sheep showed a reduced cortisol response to ACTH during week 2 irrespective of sampling method suggesting down-regulation of the response to ACTH. Maximum mean plasma progesterone concentration was reached at 15 to 30 min after ACTH administration. No significant differences in cortisol and progesterone responses due to blood sampling method were found in animals receiving prior dexamethasone treatment. This demonstrates that the ABSE has the ability to be used to effectively conduct ACTH stimulation tests without the need to handle the animals during the test.

The effect of blood sampling method on indicators of physiological stress in reindeer (Rangifer tarandus tarandus)

The effects of manual blood sampling and remote blood sampling using automatic blood sampling equipment (ABSE) on plasma cortisol and catecholamine concentrations were studied on eight adult female reindeer (Rangifer tarandus tarandus). Contemporary body temperatures and heart rates were also recorded to determine their utility as other possible stress indicators. The animals were blood sampled once every hour with ABSE on 9-10 May and then by manual blood sampling on 13-14 May. Animals were also fitted with equipment to record heart rate and body temperature. Heart rate and body temperature were also recorded continuously without blood sampling on 17-18 May in undisturbed control conditions. Plasma cortisol concentrations were five-to-six fold greater during manual blood sampling compared to sampling with ABSE (F(1,3) = 13.34, P < 0.05). Plasma noradrenaline concentrations were significantly higher (F(1,3) = 22.98, P < 0.05) during manual blood sampling compared to sampling with ABSE, whereas plasma adrenaline concentrations did not differ. Heart rate was higher during manual blood sampling compared to control values. Body temperature was significantly higher during manual sampling compared to values recorded without blood sampling (F(1,4)= 31.65, P < 0.01). In conclusion, plasma cortisol concentration provides an excellent indicator of handling stress in reindeer. The use of ABSE for blood sampling enables measurements of plasma cortisol levels close to basal concentrations that may be used for reference values in studies where indicators of physiological stress are required.

Lactate dehydrogenase quantification and isoenzyme distribution in physiological response to stress in red deer (Cervus elaphus)

As a contribution to the description of the physiological response to stress in red deer (Cervus elaphus), the potential use of the intracellular glycolytic enzyme, lactate dehydrogenase (LDH) and its isoenzyme LDH-5, as a marker of muscle damage was assessed. The distribution of LDH isoenzymes within red deer tissues was similar to that shown in other ruminants: tissue characterisation showed isoenzyme LDH-5 to be particularly associated with skeletal muscle. High plasma concentrations of creatine kinase, a muscle-specific enzyme, were associated with both high total LDH activity and the percentage of LDH-5 activity in deer undergoing a potentially stressful procedure, transportation followed by simulated abattoir lairage, which is further evidence of the specificity of the isoenzyme for skeletal muscle damage. The activity of LDH was not correlated with the plasma concentration of cortisol, a widely used physiological measure of psychological stress. This may have been due to different time courses for release and the fact that, in the present study, the immediate pre-collection procedures may have induced a short-term stress response.