An Unusual Case of Predation: Dog Pack or Cougar Attack?

Injuries produced by animals are capable of leaving severe patterns and in some cases may result in the death of the attacked individual. Law enforcement authorities may come to erroneous conclusions about the source of the bites based on their awareness of animals present and similarities of the injuries to the untrained eye, with dreadful consequences. Expertise of a carnivore biologist and an odontologist that indentifies the particularities of bite marks may be useful for identifying the attacking species. We present the investigation of a fatal dog pack attack involving a 43‐year‐old man in Bell Ville (Argentina) where the evidence provided by a forensic dentist and a biologist was categorical for establishing the animal species involved. Because of the unusual characteristics of the wounds and the initial hypothesis made by local authorities of a cougar attack, habits and specific patterns of both dog pack and cougar predation on humans are discussed.     

Interpretation of ante-mortem stature estimates in South Africans

We developed a simple method for animal species identification of humans, dogs and cats, using a multiplex single-base primer extension reaction in the cytochrome b gene. Using this method, three points of a single nucleotide in the cytochrome b gene were examined in these species using primers of different lengths. Our method was found to be able to successfully identify humans (26 samples), dogs (21 samples) and cats (9 samples), and no differences were found among the samples from each animal species in this study. The amount of template DNA required was over 0.01 ng for humans and dogs, and over 0.1 ng for cats. The present method was able to identify animal species from hair shaft (2 cm) and forensic casework samples (blood stains and hair shafts), and is thus a useful tool for animal species (human, dog and cat) identification in forensic science.     

Death caused by "attack dog" bites. A contribution to current discussion

Two cases of fatal dog-bite incidents caused by males of the "American Staffordshire terrier" breed currently known as "fighting dogs" are reported. Both happened in elderly women, one of them handicapped. Reconstruction of the accidents revealed some peculiar characteristics of these dogs, namely the ability to attack undesirably and forcefully as well as the enormous grip of their jaws. Considerable public attention has been drawn to some breeds which seem to predominate in dog-bite statistics and are summarized as "pit bulls". For the animal behaviourist it is not justifiable to condemn only the dog and blame it solely for damage inflicted. Scientific casework has to encompass the situational background of any case and the animal's holder because there is often a close association between the character of the dog and its human counterpart. Implications of such incidents for public safety policy and forensic science are to be discussed.     

Real-time polymerase chain reaction quantification of canine DNA

The accurate quantification of target DNA is an important step in the short tandem repeat analysis of forensic biological samples. By utilizing quantification data to control the amount of template DNA in the polymerase chain reaction (PCR), forensic scientists can optimize testing and minimize the consumption of limited samples. The ability to identify and quantify target DNA in mixed-species samples is crucial when it may be overwhelmed by nontarget DNA, as in cases of dog attack. We evaluated two quantitative real-time PCR assays for dynamic range, species specificity, and inhibition by humic acid. While both assays proved to be highly sensitive and discriminating, the Melanocortin-1 Receptor (MC1R) gene Taqman assay had the advantages of a shorter run time, greater efficiency, and safer reagents. In its application to forensic casework, the MC1R assay has been advantageous for quantifying dog DNA in a variety of mixed-species samples and facilitating the successful profiling of individual dogs.     

Mitochondrial profiling of dog hairs

In order to make greater use of dog hairs as forensic evidence, we have developed a robust method for duplex amplification of adjacent 306 and 332bp amplicons within the 5' hypervariable region (5' HVR) of the canine mitochondrial control region. In support of this, a 595bp region covering 35 polymorphic sites has been sequenced from the blood of 105 UK dogs. In total, 30 different haplotypes were observed, 13 only once whilst the commonest was seen 14 times; the overall exclusion capacity is 0.929. One animal was heteroplasmic in blood for a single base deletion and showed phenotypes ranging from near complete deletion to a predominance of the base among a sample of 12 hairs. In contrast, no evidence of heteroplasmy was seen in single hairs from 20 dogs which were not visibly heteroplasmic in blood. Phylogenetic analysis and comparisons with other published databases highlighted instances of possible recurrent mutation which may be relevant when interpreting single base differences between samples.     

Analysis of forensic SNPs in the canine mtDNA HV1 mutational hotspot region

A 60 bp sequence variation hotspot in the canine mitochondrial DNA hypervariable region 1 was evaluated for its use in forensic investigations. Nineteen haplotypes containing 18 single nucleotide polymorphisms were observed among laboratory-generated and GenBank-derived domestic dog sequences representing five regional localities in the U.S. Samples from the different localities were highly variable with the levels of intra-population variability being similar among the populations studied. AMOVA further confirmed that there was no significant genetic structuring of the populations. Assays using these haplotypes were robust, canid specific and portend a rapid method for correctly excluding individual dogs as noncontributors of forensic evidence. Species-specificity of the primers was confirmed by means of in-tube polymerase chain reaction of human and cat DNA and in-silico assessment of the genomes of several animal species. Breed-specific fragments were not detected among the common haplotypes but there is evidence that this assay may be capable of differentiating domestic dog, wolf, and coyote sequences.     

Forensic DNA-typing of dog hair: DNA-extraction and PCR amplification

The forensic application of DNA-typing for the identification of dog hair provides objective evidence in the characterisation of traces found at crime scenes. During the past few years forensic dog identity testing has been improved considerably using multiplex PCR systems. However, DNA-typing from samples of one up to 10 dog hairs is often problematic in forensic science. A single dog hair contains very small quantities of DNA or the hair sample consists of hairs with roots of bad quality or even of broken hairshafts without roots. Here we describe an experimental study about dog hairs by means of a Ca(2+) improved DNA-extraction method, quantification and amplification.     

The Influence of Evidence on Animal Cruelty Prosecution and Case Outcomes: Results of a Survey

Two hundred prosecuting attorneys completed a survey concerning priorities in taking on animal cruelty cases and the factors that help or hinder prosecuting such cases. Respondents commented on the priority given such cases. Questions also addressed specific kinds of evidence that had been used to decide whether to take on a cruelty case and were used in court. Results showed that prosecutors most frequently relied upon “traditional” sources of evidence, including detailed medical and crime scene reports and good quality photographic evidence. Other sources of forensic evidence such as DNA, computer forensics, forensic accounting, blood, and trace evidence were rarely employed. Veterinary forensic evidence, including forensic necropsies and detailed medical reports, was viewed as an important factor by a majority of prosecutors in deciding whether to accept a case for prosecution and in achieving a successful outcome, but a need for additional training for investigators was indicated.     

Multi-agent scavenging patterns in Hawai‘i: A forensic archaeological and skeletal case study

Knowledge of the behavior of local fauna can aid forensic investigators in developing awareness of site formation processes. In Hawai‘i, little has been published on the effects of feral domestic pig (Sus scrofa) and feral domestic dog (Canis familiaris) scavenging and bone dispersal on field recovery and laboratory observations. In this Pacific tropical setting, the most consequential terrestrial taphonomic agents are pigs and dogs, both in terms of hard tissue modification and dispersal of remains across the landscape. In 2017, an archaeologist discovered the remains of an unidentified decedent on the island of Kauaʻi, State of Hawai‘i during a cultural resource management survey. Subsequently, a forensic recovery team in conjunction with Kaua‘i police and crime scene investigators used archaeological techniques, including pedestrian survey, tape-and-compass, and GPS mapping, to map and recover the remains. A feral pig trail transected various areas of the recovery site and corresponded with the distribution pattern of recovered skeletal material, including both the main concentration more broadly dispersed skeletal elements. While much of the skeleton was present, missing or unrecovered skeletal elements are consistent with expectations based on existing literature. Much of the postmortem bone deformations were characteristic of marks related to feral dog and/or feral pig scavenging. These results assisted local investigators in deciding the manner of death, as well as providing the family with an accounting of the decedent’s remains for burial. Thus, forensic anthropologists and archaeologists need to understand and develop knowledge of local animal behavior to recover and interpret human remains of medicolegal significance.     

Extensive and mutilating craniofacial trauma involving defleshing and decapitation: unusual features of fatal dog attacks in the young

Four cases of fatal dog attacks are reported in 3 children aged 6, 10, and 11 years and in an infant aged 3 weeks. The cases were all characterized by extensive and mutilative stripping of soft tissues from the face and scalp, progressing to decapitation in the infant. The attacks were highly focused, involving 2 dogs in all but 1 case, with the area of trauma localized to the craniofacial region. The injuries resembled those found after postmortem animal depredation. The involvement of more than 1 dog may account for the severity of the injuries due to "pack" behavior. Deaths were due to exsanguination, air embolism, and decapitation. Necropsy examination of the attacking dogs revealed tissues from the victims in 2 of the animals' stomachs. These cases demonstrate the vulnerability of infants and young children to fatal dog attacks, with an unusual concentration of severe injuries to the head regions. Necropsy of the canine assailant, with collaboration between pathologists and veterinarians, is an important part of such investigations as it may provide information helping to establish the identity and ownership of the animal, along with trace evidence confirming that the dog was involved in the attack.     

Species identification in routine casework samples using the SPInDel kit

The identification of species in casework samples is of fundamental importance for forensic investigations. Laboratories are increasingly compelled to provide accurate and fast identifications in trace materials left on crime scenes, wildlife poaching, illegal trade of protected species, fraudulent food products cases, etc. However, the field of nonhuman forensic genetics is still working on the standardization of typing methods and practices. Here we describe the successful implementation of the Species Identification by Insertions/Deletions (SPInDel) method in routine casework analyses in 11 laboratories worldwide. The SPInDel was developed to detect human DNA, at the same time that identifies common animal species. The fragment size analysis of six mtDNA regions allows identification in suboptimal DNA samples, including mixtures, with no need for sequencing. The samples were collected from 2013 to 2018 and included hair, blood, meat, saliva, faeces, bones, etc. The SPInDel kit successfully identified >95% of the samples, being dog, human and pig the most frequently detected species. The six SPInDel loci were successfully amplified in mixtures and degraded samples (river water, sand, stains in clothes, etc.). Interestingly, several species that were not originally targeted by SPInDel primers were also identified (e.g., red fox, brown bear, fallow deer and red deer). In conclusion, the SPInDel kit was successfully used in crime scene investigations (often involving human DNA detection) and in cases of poaching, environmental contamination and food fraud. It is now becoming a useful tool for the routine analysis of nonhuman DNA samples within the high quality standards of forensic genetics.     

D20S161和D8S384两个基因座在法医学中的应用

评估D2 0S16 1和D8S384两个基因座在法医学中的应用价值。用自制的D2 0S16 1和D8S384两个DNA分型试剂盒 ,对人血、人精液、人唾液、动物血、人血与动物血的混合检材和人血痕、人精液斑、人唾液斑、动物血痕、人血与动物血的混合斑痕检材 ,以及陈旧血痕检材进行检测分型 ,并用这两个基因座PCR引物序列与DNA数据库进行联网对比分析。自制的D2 0S16 1和D8S384两个DNA分型试剂盒能对人血、人精液、人唾液、人血与动物血的混合检材分型 ,而动物血没有PCR产物 ;自制的D2 0S16 1和D8S384两个DNA分型试剂盒能对人血痕、人精斑、人唾液斑和人血与动物血的混合斑痕检材正确分型 ,而动物血痕没有PCR产物 ;斑痕检材分型结果与对应体液检材分型结果无差异 ;5 0份陈旧血痕检材全部获得阳性分型结果。DNA数据库联网比较提示 ,D2 0S16 1和D8S384基因座引物除了能与各自的模板序列发生特异性扩增外 ,理论上不能与DNA数据库中 6 0 6 36 4种已知序列产生PCR产物。D2 0S16 1和D8S384两个基因座具有高度的种属特异性 ,抗污染能力强 ,不易受降解的影响 ,是解决法医现场生物检材个人识别和亲子鉴定的理想手段     

Behavior of animal blood in blood typing systems. Isoelectric focusing of erythrocyte acid phosphatase and phosphoglucomutase

Isoenzyme band patterns of animal blood erythrocyte acid phosphatase (EAP) and phosphoglucomutase-1 (PGM) were studied by isoelectric focusing on ultrathin polyacrylamide gels. For blood from all animals tested (dog, cat, cow, sheep, and goat), the overall band patterns for both isoenzymes were different from those of the most common human types of these enzymes, although some animal EAP and PGM bands appeared in the human band areas. When mixtures of human and animal red blood cells were studied, it was found that misinterpretation of human types was possible only if the overall band pattern of the mixtures was ignored. For the animal blood tested, the strong PGM bands appearing outside the human band areas could be used as "markers" for the possible presence of animal blood in the samples tested.     

呼和浩特夏秋季嗜尸性苍蝇群落组成与演替

目的研究呼和浩特夏秋季常见嗜尸性苍蝇生态群落组成与演替规律。方法连续3年用观察法研究7—10月份,家兔、狗尸体、鸡、鱼内脏等试验材料上的嗜尸性苍蝇生态群落组成与演替。结果该地区上述尸体上出现的双翅目嗜尸性苍蝇是最先到达尸体上的昆虫,而且在尸体上出现时间及部位表现出很强的生态群落演替规律性。结论研究结果可成为在呼和浩特地区对尸体进行死亡时间、死亡地点推断的依据。     

A multidisciplinary investigation of chronic animal abuse: Collaboration between veterinary forensics and forensic anthropology

An unknown juvenile female mixed breed dog was found non‐ambulatory on a dead‐end street in an urban setting adjacent to a public park. During initial veterinary examination, she was assessed to have untreatable injuries and was humanely euthanized. The forensic veterinarian requested consultation from a forensic anthropologist to assist with documenting antemortem skeletal trauma. Analyses of skeletal tissues indicated numerous injuries in various stages of healing diagnostic of non‐accidental injuries. Veterinary forensic cases may benefit from collaborative analysis of bony remains by forensic anthropologists.     

Forensic scatology: preliminary experimental study of the preparation and potential for identification of captive carnivore scat

Carnivore scats recovered from animal attack and/or scavenging contexts frequently contain forensic evidence such as human bone fragments. Forensic cases with carnivore involvement are increasingly prevalent, necessitating a methodology for the recovery and analysis of scat evidence. This study proposes a method for the safe preparation of carnivore scat, recovery of bone inclusions, and quantification and comparison of scat variables. Fourteen scats (lion, jaguar, lynx, wolf, and coyote) were prepared with sodium-acetate-formalin fixative; analytical variables included carnivore individual, species, body size, and taxonomic family. Scat variables, particularly bone fragment inclusions, were found to vary among carnivore individuals, families, species, and sizes. The methods in this study facilitate safe scat processing, the complete recovery of digested evidence, and the preliminary identification of involved animals. This research demonstrates that scat collected from forensic contexts can yield valuable information concerning both the victim and the carnivore involved.     

Domestic Predation of an Elder: A Fatal Dog Attack Case

We present the case of a 91‐year‐old woman lived alone at her home with two domestic dogs, that is,, a Labrador Retriever and a Staffordshire Bull Terrier and found dead. The investigation of the scene revealed that the Bull Terrier's jawbone and chest were covered with blood. The autopsy revealed multiple, histologically confirmed, life‐threatening skin and bone lacerations without scavenging marks. The punctures and tearing of each of the wounds on the skin were compatible with bites. A left humeral fracture and multiple fractures of the right facial bones were observed. The death was attributed to external hemorrhages due to several dog bites. A veterinary physical and behavioral examination indicated that the Bull Terrier was involved in the attack. A domestic predation hypothesis was deemed here most likely due to the presence of food supplies at the scene, the dog's previous history of attack, and the breed of the dog.     

Comparative radiographic study of human and animal long bone patterns

The objective of this study was to test the hypothesis that certain radiographic features can be found to distinguish between human and animal long bone fragments, and therefore would be useful as an adjunct in forensic science identification. Using proposed radiographic criteria, 13 archeologists and 12 dentists were asked to identify 20 radiographic samples as representing human or animal bone. Results showed that archeologists correctly identified 86.8% of the samples, and dentists correctly identified 81.9%. Based on the results of this study, it was concluded that radiographic interpretation of long bone fragments may be a useful aid in a forensic science investigation of human and animal remains.     

动物DNA分析在法庭科学中的应用

近年来,在法庭科学领域中,遇到越来越多的非人类DNA分型的问题,特别是来源于动物本身或者是动物的分泌物。作为证据,通过对犯罪现场非人类DNA的分型,不但可以知道在何地对何人或何物实施犯罪,而且,如果犯罪的实施方是动物,也可以知道其来自哪里。目前,在法医学领域,有关动物DNA分析方法的标准较少。根据国际法医遗传学会最新的研究成果,综述动物DNA在法庭科学中的应用现状和相关建议。