Peer Reviewed Evaluation of the Potential for Injury With Remote Drug-Delivery Systems MARC R. L. CATTET, 1 Canadian Cooperative Wildlife Health Centre, Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada ALBERT BOURQUE, Government of the Northwest Territories—Department of Resources, Wildlife and Economic Development, Yellowknife, NT X1A 2P9, Canada BRETT T. ELKIN, Government of the Northwest Territories—Department of Resources, Wildlife and Economic Development, Yellowknife, NT X1A 2P9, Canada KRAMER D. POWLEY, Royal Canadian Mounted Police—Forensics Laboratory, Regina, SK S4P 3J7, Canada DEAN B. DAHLSTROM, Royal Canadian Mounted Police—Forensics Laboratory, Regina, SK S4P 3J7, Canada NIGEL A. CAULKETT, Department of Small Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada Abstract We evaluated the potential for different types of remote drug-delivery systems (RDDS) to injure target animals. We recorded dart velocity, time, and distance from projector muzzle at 8.5-millisecond intervals by Doppler radar chronograph for 4 types of RDDS. We used darts of different volume and unique combinations of charges, power settings, and distances in accordance to manufacturer’s recommendations. Variation in the drop of repeated shots was .10 cm for 28 of 90 trials (5 replicates per trial) with heavy-mass darts having the lowest precision. Impact velocities were high (.50 m/sec) in many trials using heavy darts and some trials using light-mass, rapid-injection darts. We evaluated the permanent wound cavity (PWC) formed by firing dye-filled darts into ordnance gelatin covered tightly by a fresh elk hide and into the thighs of calf carcasses. Rapid-injection darts fitted with end-ported needles consistently 1) forced hair and skin beneath the hide; 2) formed a PWC that was 2–3 3 the needle length; and 3) pulled the hide away from the gelatin before the dye was completely ejected into the gelatin. We conclude injury to target animals is minimized in RDDS that use lightweight, slow-injection darts, fitted with side-ported needles and broad-diameter needle seals, and that impact target animals at moderate velocity (40–50 m/sec) with high precision. We recommend against using darts with rapid- injection mechanisms and end-ported needles because of their potential to cause deep, chronic wounds. (WILDLIFE SOCIETY BULLETIN 34(3):741–749; 2006) Key words dart, injury, ordnance gelatin, permanent wound cavity, precision, rapid-injection, remote drug-delivery systems, slow-injection, velocity. The development of reliable remote drug-delivery systems (RDDS) in conjunction with safer anesthetic drugs over the past 4 decades has greatly facilitated the capture and handling of many different free-ranging species and the medical care of zoo animals (Harthoorn 1970, Bush 1992). Today, the large variety of commercial RDDS available creates a challenge to select the appropriate one. Some guidance can be obtained through published reviews and technical manuals that highlight the strengths and weaknesses of different RDDS ( Jones 1976, Kock 1987, Bush 1992, Nielson 1999, Kreeger et al. 2002). The possibility that RDDS can cause significant injury has been noted by some authors (Thomas and Marburger 1964, Smith and Huse 1980, Valkenburg et al. 1983, Spurlock and Spurlock 1988). However, most injury has been attributed to user inexperience or inappropriate use of the drug-delivery system ( Jessup 2001). Minimal attention has been directed toward design features or manufacturer’s recommendations that also might cause injury. An exception is the study by Valkenburg et al. (1999) in which the velocity, consistency, and penetration of darts was compared between CO 2 - and powder-charge-propelled darts. Despite widespread use of RDDS, the potential for injury in target animals remains largely unknown because the contributing factors have not been clearly identified. Further, it is likely the frequency of injury is underestimated because many dart injuries go undetected, concealed well by fur and skin. Although the development of RDDS has progressed over the years, more controlled laboratory studies and experimentation in the field are needed to further reduce morbidity or mortality caused by this equipment. Using techniques employed to study wound ballistics in humans (Fackler 1988, MacPherson 1994, Haag and Haag 2002), we determined, in a controlled laboratory study, some of the characteristics of RDDS that could contribute to injury in target animals. We then used this information to assess the potential for injury using different types of RDDS selected primarily on the basis of dart mass and mechanism of drug injection. Methods We conducted the study on an indoor firing range at the Royal Canadian Mounted Police (RCMP) Forensics Laboratory at Regina, Saskatchewan, Canada (50827 0 00 00 N–104837 0 00 00 W) in September 2003. We tested 4 different remote drug-delivery systems selected to represent both a wide range in dart mass (heavy vs. light) and 2 different mechanisms of drug injection (rapid vs. slow; Table 1). The rapid-injection darts expel their liquid content by means of a powder charge placed between the rubber plunger and tailpiece that detonates upon impact and quickly advances the plunger. The slow-injection darts rely upon compressed air to 1 E-mail: marc.cattet@usask.ca Cattet et al.  Remote Drug-Delivery System Injuries 741