Who is who? Identification of livestock predators using forensic genetic approaches

Abstract

Molecular identifications of salivary DNA are increasingly applied in wildlife forensic investigations, and are successfully used to identify unknown livestock predators, or elucidate cases of large carnivore attacks to humans. In Europe most of livestock predations are attributed to wolves (Canis lupus), thought free-ranging dogs are sometime the responsible, and false predations are declared by breeders to obtain compensations. In this study we analyzed 33 salivary DNA samples collected from the carcasses of 13 sheep and a horse presumably predated by wolves in seven farms in central Italy. Reliable individual genotypes were determined in 18 samples (corresponding to samples from nine sheep and the horse) using 12 unlinked autosomal microsatellites, mtDNA control-region sequences, a male-specific ZFX/ZFY restriction-site and four Y-linked microsatellites. Results indicate that eight animals were killed by five wolves (a male and four different females), the ninth by a female dog while the horse was post-mortem consumed by a male dog. The genotype of one female wolf matched with the genetic profile of a female wolf that was non-invasively sampled 4 years before in the same area near livestock predation remains. Genetic identifications always supported the results of veterinary reports. These findings show that salivary DNA genotyping, together with detailed veterinary field and necropsy reports, provides evidence which helps to correctly identify species, gender and individual genetic profiles of livestock predators, thus contributing to clarify attack dynamics and to evaluate the impact of wolf predations on husbandry.