Comparison of the use of an Electronic Control Device to chemical restraint for short term capture and release in reindeer (Rangifer tarandus tarandus)

Electronic Control Devices (ECDs) have potential to be effective alternatives to chemical restraint for short-term capture and release of wildlife. To assess immediate and delayed physiologic effects of chemical restraint... [ view full abstract ]

Electronic Control Devices (ECDs) have potential to be effective alternatives to chemical restraint for short-term capture and release of wildlife. To assess immediate and delayed physiologic effects of chemical restraint (carfentanil/xylazine (CX)), and exposure to an ECD, we randomly assigned 15 captive reindeer to one of three treatment/intervention groups: anesthetized with CX, 30 second exposure to an ECD, or exposure to the ECD while anesthetized with CX (ECD+CX). Blood samples were collected pre-treatment (T0), immediately post-intervention (Tc), 10 min (T1), 20 min (T2), 4 hours (T3) and 24 hours (T4) post-intervention. Physiologic effects were evaluated by analysis of blood, clinical observation for signs of physiologic compromise, and vital signs. For many parameters (BUN, ALT, AST, etc) there was little change from baseline and values remained within expected ranges. Parameters that did change post-exposure (eg. glucose, body temperature, blood oxygen, cardiac troponin I (cTnI), cortisol, catecholamines) returned to within baseline by 24 hours. The decrease in blood oxygen found with chemical restraint was not present in the ECD exposed individuals. Temperature increased from baseline at T1 and T2 in all groups, but didn’t vary significantly by group at any time point. Glucose and cortisol increased in all animals at T1 and T2, decreasing towards baseline by T3. Increases in cortisol and glucose were greatest for the CX and ECD+CX groups. Immediately post-intervention (Tc), epinephrine and norepinephrine increased in the ECD and ECD+CX groups, but decreased slightly in the CX group; all catecholamine levels returned to baseline by T3. Although a slight transient increase in cTnI was detected in some individuals (especially in the ECD+CX group), the levels were below what is reported with myocardial necrosis in other species, and returned to baseline by 24 hours. No long term health effects nor impacts on lactation/pregnancy were detected from either restraint method.