Comparison of Sampling Methods for mtDNA Analysis for Identification of Predator Species Causing Wounds in Veterinary Forensic Cases.

In forensic veterinary investigations of suspicious animal deaths involving loss of body parts, it is essential to determine whether the wounds were caused by human intervention or by other animals. Detailed postmortem examination of the wounds, combined with DNA analysis to identify biological traces left by the offending animal, play a critical role in such cases. Two primary methods are available for sample collection: muscle tissue sampling from the wound site and surface swabbing of the wound area; however, comparative studies evaluating these two approaches remain limited. In this study, mitochondrial DNA (mtDNA) analysis was performed using both muscle tissue sampling and surface swabbing in three forensic veterinary necropsy cases involving suspicious animal deaths with wounds or missing body parts, with the aim of identifying the animal species responsible for the injuries. As a result, in Case 1, canine DNA was detected from the wound of a cat carcass using both sampling methods. In Case 2, canine DNA was detected only with the swab method from the wound of another cat carcass. In Case 3, feline DNA was detected only with the muscle tissue sampling method from the wound of a duck carcass. Muscle tissue sampling, which targets deep tissues, offers advantages in preserving DNA integrity and quality. In contrast, the surface swab sampling is non-invasive and enables sample collection over a broader surface area, making it a valuable complementary tool. Although this study is based on a small number of cases, the findings suggest that combining both sampling techniques in wound-associated DNA analysis can leverage the strengths of each method, thereby improving DNA detection efficiency and enhance the reliability of forensic examinations.