Organized dogfighting is a crime in which 2 dogs, usually of the same sex and similar weight, are fought until a dog is unable or unwilling to continue, a handler concedes, or, on rare occasions, a dog dies. In addition to animal abuse and illegal gambling, dogfighting is often associated with organized crime, racketeering, illicit drugs, illegal firearms, and other forms of violence.1–6 As of 2009, dogfighting is a felony in all 50 states of the United States, and interstate movement of dogs for fighting purposes is a federal felony.2,4–6
In the United States, the American Pit Bull Terrier is the breed most commonly associated with organized dogfighting.1,3,4 The popularity of this breed in organized fighting is thought to be attributable to breed traits such as strength, stamina, agility, pain tolerance, aggression toward other animals, and willingness or desire to fight despite injury or fatigue, a trait referred to as gameness.1–6
Dogs are typically first placed in a controlled fight that serves as a training exercise at approximately 1 year of age.1,2 This is termed rolling and is usually done several times—a process referred to as schooling—before they are entered into a contract fight. In a contract fight, dogs are typically matched by weight and sex.1,4 Although most fights documented in underground fighting publications are between male dogs, organized fights between female dogs are not uncommon, as the value of male and female fighting dogs as breeding stock is increased substantially by a recorded history of winning fights.2,4
Although most contract matches are not fought to the death, losing animals may be tortured and killed by angry or embarrassed owners. Even winning dogs can sustain extensive injuries, including deep puncture wounds, fractured bones and teeth, wounds of the buccal and gingival mucosa, dehydration, and infection. Some of these injuries may result in death.1–6
To avoid detection by authorities, many dogfighters attempt to treat their injured animals themselves rather than seek professional veterinary care.1–6 When these individuals do seek veterinary care, they may provide a variety of explanations for their dog's injuries. A frequent claim is that the dog was involved in a spontaneous fight, or so-called yard accident.1–5 Veterinarians are not traditionally trained to recognize nonaccidental injuries, such as those that occur during an organized dogfight; therefore, injuries suggestive of or consistent with organized dogfighting might not be reported to appropriate authorities in cases where professional veterinary care is sought.
Most canine aggression is highly ritualized. During a spontaneous fight, dogs with normal social behavior inhibit their bites and stop fighting when the other dog shows signs of submission, such as whining, turning away, or rolling over.1,3,7 It has previously been thought that bites tend to be directed to the scruff, shoulder, and haunches in these spontaneous fights and that only a few bites may produce puncture wounds the full depth of the canine teeth.1,3 In contrast, veterinarians who regularly work with law enforcement on cases of organized dogfighting report that dogs that are intentionally fought frequently have wounds on the head, forelegs, and chest.1–4 These injuries are usually numerous and often severe, including deep puncture wounds, avulsions of the skin from the underlying tissue, and occasional underlying fractures.1–3 The prevailing theory is that dogs used in organized fights are bred and trained to have reduced bite inhibition—inflicting maximum damage on their opponents rather than only driving them away—and to continue to face their opponent and fight in spite of their own injuries.1,3 Additionally, such dogs may have wounds present that are in different stages of healing, which would be indicative of multiple instances of trauma and thus not consistent with the claim of a single spontaneous fight.1–3
Several studies8–12 have examined the locations of injuries sustained in dogfights, but to the authors' knowledge, no study has been performed with the intent of differentiating between wounds sustained in spontaneous versus organized dogfighting. The purpose of the study reported here was to evaluate the types and prevalence of injuries found in a population of dogs involved in spontaneously occurring dogfights and to compare these with those of dogs known to have been used in organized dogfighting. It was hypothesized that dogs that had not been bred and trained for fighting but were involved in spontaneously occurring dogfights would have different patterns of injury than those of dogs involved in organized dogfighting. The goal was to establish evidence-based patterns of injury as a means to help clinicians identify signs of organized dogfighting and aid in the prosecution of this crime.
Materials and Methods
Criteria for selection of dogs involved in spontaneous fights
All dogs evaluated at the Foster Hospital for Small Animals at the Cummings School of Veterinary Medicine at Tufts University for injuries related to fighting with another dog between January 1, 2003, and June 1, 2014, were eligible for study inclusion. The hospital acts as a primary emergency facility and regional referral hospital.
Spontaneous fighting was categorized as BDLD (in which injury resulted from a fight between a small dog and a larger dog, irrespective of sex) or MDMD (in which a medium-sized dog was injured in a fight with another dog of the same sex and similar weight) on the basis of information available in the medical record. Dogs involved in BDLD fights were included not because the injuries were expected to be similar to those incurred in organized fighting, but because dogs injured in this type of spontaneous fighting are commonly seen by veterinarians, and the mechanism, and therefore the pattern, of injury is thought to be distinct from those incurred by other types of dogfighting.13–16 This category was included to help determine whether the methods used in this study could differentiate between injuries incurred in different types of dogfights. The dogs seen following MDMD fights were included because these were considered the best population for comparison with those involved in organized dogfighting, where dogs are typically matched by sex and weight.
Criteria for selection of dogs in BDLD fights—Dogs were identified through a keyword search of the hospital's electronic medical records system with the search terms “big dog little dog” and “BDLD.” The term BDLD was used in the hospital to describe incidents in which smaller dogs were injured by larger dogs (often having been grabbed and shaken); however, there were no specific criteria for what constituted a small dog, and thus, the use of the term BDLD to describe an incident relied on the clinician's discretion. Dogs were excluded if the fight involved > 2 dogs, if the cause of injury was assumed but not definitively known to be a BDLD fight, if a complete physical examination was not performed or documented, or if they were < 6 months of age.
Criteria for selection of dogs in MDMD fights—A keyword search of the hospital's electronic medical records system was performed with the search terms “dog fight,” “dog bite,” and “bite wound.” Dogs were excluded if the fight involved > 2 dogs, if the injury was assumed but not definitively known to result from an MDMD fight, if a complete physical examination was not performed or documented, or if they were < 6 months of age. Dogs were also excluded if the owner reported that the injury was an accident that occurred while the 2 dogs were playing, if the fight occurred through a fence or barrier, if the fight occurred > 7 days before the examination, or if the dog was known to have been rescued from an illegal organized dogfighting operation. Finally, to provide the best comparison with the conditions of organized dogfighting, dogs were excluded if they weighed < 12 kg (26.4 lb) or > 42 kg (92.4 lb), if the weight and sex of the other dog in the fight was not reported, if the other dog was not of the same sex as the patient, or if the weight difference between the 2 dogs was > 5 kg (11 lb).
Criteria for selection of dogs involved in organized dogfights
Case dogs were those that were seized in connection with dogfighting law enforcement raids and examined between May 2, 2009, and March 26, 2013, and had electronic medical records made available from the American Society for the Prevention of Cruelty to Animals and Commonwealth of Virginia Department of Agriculture and Consumer Services. Dogs were excluded if they were < 2 years of age (as it was unlikely that they would have been previously fought in a contract match), if there were no wounds or scars reported, or if no wound and scar diagram (also known as a scar chart) was available.
Procedures
Medical records were reviewed, and data were collected by use of a standard data collection sheet. Demographic variables recorded were breed, body weight, age, sex, and spay or neuter status. For dogs involved in MDMD fights, the weight difference between the 2 dogs was also recorded, and BCS (determined on a scale of 1 to 9 as described elsewhere17) was recorded if available. For dogs used in organized fighting that did not have weight reported, BCS (according to the same scale) was noted instead.
To record the anatomic location and extent of injury to integument or eyes, the body surface was initially divided into 51 sections that were based on division of a drawing of a generic dog into roughly equal parts. For each section, a value of 1 was assigned if wounds or scars were present, and a value of 0 was assigned if no wounds or scars were indicated. The 51 sections were then grouped into 13 larger zones, each roughly corresponding to a clinically useful anatomic location. Then the extent of injury in each zone was calculated by adding together the numeric values of the combined sections. For example, if a given dog had wounds or scars in the dorsal cervical section and left lateral cervical section but not the right lateral cervical section, the assigned numeric values would be 1, 1, and 0, respectively. When these 3 sections were combined to form a larger, more clinically useful body surface zone (comprising the dorsal and lateral aspects of the neck), the extent of injury in that zone would be calculated as 2 (1 + 1 + 0).
The 13 body surface zones were the dorsal and lateral aspects of the head, the eye and periorbital region, the pinnae, the muzzle and oral mucosa, the dorsal and lateral aspects of the neck, the ventral neck and thoracic region, the scapular region, the thoracic limbs, the thoracic and lumbar vertebral region, the lateral thoracic and abdominal region, the ventral thoracic and abdominal region, the pelvic limbs, and the pelvis and tail (Figure 1). Apart from wounds and scars of the integument or eyes, different skeletal fractures and dental injuries were assigned a value of 1 if present or 0 if absent. Mean group scores for each injury type and location were then calculated.
Illustration depicting 13 body surface zones used to record anatomic location and calculate extent of injury to the integument or eyes in a study to characterize and compare patterns of injuries incurred in spontaneous versus organized dogfights. Zones are indicated by number as follows: 1 = dorsal and lateral aspects of the head, 2 = eye and periorbital region, 3 = pinnae, 4 = muzzle and oral mucosa, 5 = dorsal and lateral aspects of the neck, 6 = ventral neck and thoracic region, 7 = scapular region, 8 = thoracic limbs, 9 = thoracic and lumbar vertebral region, 10 = lateral thoracic and abdominal region, 11 = ventral thoracic and abdominal region, 12 = pelvic limbs, and 13 = pelvis and tail.
Citation: Journal of the American Veterinary Medical Association 251, 12; 10.2460/javma.251.12.1424
Data analysis
Data were analyzed by use of standard statistical software.a According to the central limit theorem, which states that the distribution of the sample means for any population will be approximately normal provided that the sample size is sufficiently large (generally considered to be ≥ 30),18 use of nonparametric tests was unnecessary.
A 1-factor ANOVA was performed to compare extent of injury scores for each injury type and location among the 3 groups of dogs (BDLD, MDMD, and organized fighting dogs). Values of P < 0.05 were considered significant.
To determine the prevalence of injuries for each of the 3 groups of dogs, the percentage of dogs in each group that incurred body surface injury in each zone or had dental trauma or specific skeletal injuries was calculated. Patterns of injury for each group were then described on the basis of prevalence data; the 5 or 6 body surface zones or types of skeletal or dental injury with the highest prevalence were selected to represent a pattern of injury for each group, and these patterns of injury were then graphically compared.
Results
The veterinary hospital medical records search identified 225 dogs thought to be involved in BDLD incidents. Of those, 17 had been in fights that involved > 1 other dog, 20 were not definitively known to have been injured in a BDLD fight, 9 did not have a complete physical examination recorded, and 19 were < 6 months of age. The remaining 160 dogs met the inclusion criteria for the study.
The search of the same medical records system identified 2,121 dogs potentially involved in MDMD fights. Of those, 1,269 dogs weighed between 12 and 42 kg, were > 6 months of age, and had complete medical records. Of the 1,269 dogs, 53 had been involved in a fight with multiple dogs, 344 had wounds but were not definitively known to have been in a dogfight, 33 were evaluated at the behavioral service of the small animal hospital only (and thus did not receive medical treatment at the hospital), 72 were evaluated for another condition (not wounds) and had only a mention of fighting in their history, 1 was bitten through a fence, 2 were rescued from an organized dogfighting operation, 703 did not have sex or weight information recorded for the other dog in the fight, and 25 were involved in fights with another dog of the same sex but the weight difference between the dogs was > 5 kg. The remaining 36 dogs met the study inclusion criteria.
Records of 143 dogs seized by the American Society for the Prevention of Cruelty to Animals or the Commonwealth of Virginia in connection with organized dogfighting were available for analysis. Of the 143 dogs, 51 were < 2 years of age, 23 had no wounds or scars identified, 5 had no wound and scar diagram available, and 2 had incomplete physical examination data. The remaining 62 dogs thus met the study inclusion criteria.
Of the 160 dogs involved in BDLD fights, 26 (16.3%) were sexually intact males, 64 (40%) were castrated males, 17 (10.6%) were sexually intact females, and 53 (33.1%) were spayed females. Of the 36 dogs involved in MDMD fights, 2 (5.6%) were sexually intact males, 11 (30.6%) were castrated males, 2 (5.6%) were sexually intact females, and 21 (58.3%) were spayed females. Of the 62 dogs involved in organized dogfighting, 32 (51.6%) were sexually intact males and 30 (48.4%) were sexually intact females.
The most commonly represented breeds among the 160 dogs involved in BDLD fights were Yorkshire Terriers and Yorkshire Terrier crosses (24 [15%]), Chihuahuas and Chihuahua crosses (17 [10.6%]), Shih Tzus and Shih Tzu crosses (12 [7.5%]), and Bichons Frises (12 [7.5%]). Of the 36 dogs seen for MDMD fights, the breeds most commonly identified were pit bull–type dogs and pit bull crosses (8 [22.2%]), Beagles and Beagle crosses (3 [8.3%]), Australian Cattle Dogs (2 [5.6%]), Labrador Retriever crosses (2 [5.6%]), Doberman Pinschers (2 [5.6%]), and Border Collie crosses (2 [5.6%]). All 62 of the dogs seized from organized dogfighting operations were pit bull–type dogs.
The mean ± SD age for the 149 dogs that were involved in BDLD fights and had data available was 6.3 ± 3.8 years, and that for the 36 dogs involved in MDMD fights was 4.7 ± 2.6 years. Age was estimated on the basis of dentition for 35 of the 62 dogs involved in organized fighting, with a mean ± SD estimate of 3.3 ± 0.9 years.
Weight data were available for 77 dogs involved in BDLD fights and 36 involved in MDMD fights, with mean ± SD values of 6.1 ± 3.0 kg (13.4 ± 6.6 lb) and 27.8 ± 9.6 kg (61.2 ± 21.1 lb), respectively. The mean ± SD weight difference between the dog of record and the other dog involved in a given MDMD fight was 1.6 ± 1.3 kg (3.5 ± 2.9 lb). Weight information was available for only 3 of the 62 dogs involved in organized dogfighting; these dogs weighed 20.5 kg (45.1 lb), 17.7 kg (38.9 lb), and 20.4 kg (44.9 lb). Summary data were not calculated for these dogs because the subgroup information was from a single source of data and not considered representative of the sample. However, BCS data were available for all 62 dogs used in organized dogfights (mean ± SD score, 4 ± 1.3 on the 9-point scale). In contrast, BCS was recorded for only 14 of the 36 dogs involved in MDMD fights, and these had a mean ± SD score of 5.7 ± 0.7. These 14 dogs included 6 pairs of dogs that had fought against each other; the mean difference in BCS between the 2 dogs in a given fight was 0.8 ± 0.8.
The prevalence of injury in each of the 13 body surface zones, as well as the skeletal and dental injuries recorded, is summarized (Table 1). The results of the ANOVA comparing extent of injury scores among dogs involved in BDLD, MDMD, and organized fights are reported (Table 2). The mean extent of injury scores differed significantly among the 3 groups for all body surface zones except for the eye and periorbital region. Of the skeletal and dental injuries, only the mean scores for missing, loose, or fractured teeth and rib fractures differed significantly among groups.
Prevalence of injuries caused by fighting in 258 dogs in a retrospective study to characterize and compare injuries incurred in spontaneous and organized dogfights.
| Variable | BDLD (n = 160) | MDMD (n = 36) | Organized dogfighting (n = 62) |
|---|---|---|---|
| Injuries of integument or eyes (body surface zone) | |||
| Dorsal and lateral aspects of the head* | 15 (9) | 7 (19) | 58 (94) |
| Eye and periorbital region | 25 (16) | 3 (8) | 11 (18) |
| Pinnae | 6 (4) | 16 (44) | 34 (55) |
| Muzzle and oral mucosa* | 2 (1) | 9 (25) | 55 (89) |
| Dorsal and lateral aspects of the neck* | 42 (26) | 15 (42) | 45 (73) |
| Ventral neck and thoracic region | 17 (11) | 5 (14) | 36 (58) |
| Scapular region | 12 (8) | 1 (3) | 27 (44) |
| Thoracic limbs* | 14 (9) | 15 (42) | 60 (97) |
| Thoracic and lumbar vertebral region | 32 (20) | 0 (0) | 6 (10) |
| Lateral thoracic and abdominal region | 56 (35) | 0 (0) | 17 (27) |
| Ventral thoracic and abdominal region | 27 (17) | 1 (3) | 13 (21) |
| Pelvic limbs | 21 (13) | 6 (17) | 32 (52) |
| Pelvis and tail | 9 (6) | 1 (3) | 9 (15) |
| Missing, loose, or fractured teeth | 5 (3) | 0 (0) | 25 (40) |
| Fractures of the head | 9 (6) | 0 (0) | 3 (5) |
| Mandible | 9 (6) | 0 (0) | 2 (3) |
| Maxilla | 0 (0) | 0 (0) | 1 (2) |
| Skull | 2 (1) | 0 (0) | 0 (0) |
| Vertebral fractures | 8 (5) | 0 (0) | 0 (0) |
| Rib fractures | 22 (14) | 0 (0) | 0 (0) |
| Pelvic or sacral fractures | 4 (3) | 0 (0) | 0 (0) |
Data shown are the number (%) of dogs with injuries (wounds or scars of the integument or eyes or dental or skeletal injuries) in each location. The BDLD group comprised dogs that had been involved in a spontaneous fight with a larger dog, and the MDMD group comprised medium-sized dogs (body weight, 12 to 42 kg [26.4 to 92.4 lb]) that had spontaneously fought with another dog of the same sex and similar size (body weight difference, ≤ 5 kg [11 lb]); the dogs in both of these groups were selected from dogs that were evaluated at a single veterinary teaching hospital. The organized dogfighting group comprised dogs that had been seized in connection with dogfighting law enforcement raids.
Body surface zones that were among the most common sites of injury in both the MDMD and organized dogfighting groups.
Mean ± SD extent of injury scores for the same 258 dogs as in Table 1.
| Variable | BDLD (n = 160) | MDMD (n = 36) | Organized dogfighting (n = 62) | P value |
|---|---|---|---|---|
| Injuries of the integument or eyes (body surface zone) | ||||
| Dorsal and lateral aspects of the head* | 0.10 ± 0.32 | 0.22 ± 0.49 | 2.40 ± 0.90 | < 0.001 |
| Eye and periorbital region | 0.21 ± 0.52 | 0.08 ± 0.28 | 0.23 ± 0.53 | 0.34 |
| Pinnae* | 0.05 ± 0.27 | 0.50 ± 0.61 | 0.95 ± 0.93 | < 0.001 |
| Muzzle and oral mucosa* | 0.01 ± 0.11 | 0.39 ± 0.84 | 2.47 ± 1.16 | < 0.001 |
| Dorsal and lateral aspects of the neck* | 0.41 ± 0.78 | 0.44 ± 0.56 | 1.24 ± 1.04 | < 0.001 |
| Ventral neck and thoracic region* | 0.11 ± 0.31 | 0.17 ± 0.45 | 1.05 ± 1.11 | < 0.001 |
| Scapular region* | 0.11 ± 0.46 | 0.06 ± 0.33 | 0.71 ± 0.97 | < 0.001 |
| Thoracic limbs* | 0.09 ± 0.31 | 0.53 ± 0.74 | 5.03 ± 2.39 | < 0.001 |
| Thoracic and lumbar vertebral region† | 0.24 ± 0.52 | 0 | 0.18 ± 0.64 | 0.039 |
| Lateral thoracic and abdominal region† | 0.53 ± 0.82 | 0 | 0.47 ± 0.88 | 0.001 |
| Ventral thoracic and abdominal region* | 0.19 ± 0.44 | 0.03 ± 0.17 | 0.32 ± 0.70 | 0.016 |
| Pelvic limbs* | 0.18 ± 0.50 | 0.25 ± 0.65 | 1.15 ± 1.55 | < 0.001 |
| Pelvis and tail* | 0.06 ± 0.27 | 0.03 ± 0.17 | 0.16 ± 0.41 | 0.046 |
| Missing, loose, or fractured teeth* | 0.03 ± 0.18 | 0 | 0.44 ± 0.56 | < 0.001 |
| Fractures of the head | 0.07 ± 0.30 | 0 | 0.05 ± 0.22 | 0.35 |
| Mandible | 0.06 ± 0.23 | 0 | 0.03 ± 0.18 | 0.29 |
| Maxilla | 0 | 0 | 0.02 ± 0.13 | 0.21 |
| Skull | 0.01 ± 0.11 | 0 | 0 | 0.54 |
| Vertebral fractures | 0.05 ± 0.22 | 0 | 0 | 0.08 |
| Rib fractures† | 0.14 ± 0.35 | 0 | 0 | 0.001 |
| Pelvic or sacral fractures | 0.03 ± 0.16 | 0 | 0 | 0.29 |
For each dog, wounds or scars of the integument or eyes were mapped to 1 of 51 separate anatomic regions (created by dividing a generic dog diagram into roughly equal sections). Each of the 51 regions was then scored as 1 (wounds or scars present) or 0 (wounds or scars absent). The 51 anatomic regions were then grouped into 13 larger, more clinically useful body surface zones, and the extent of injury score for each zone was calculated by adding together the numeric values that had been assigned to each region contained within the zone. Dental and skeletal injuries were scored as 1 (present) or 0 (absent). Values of P < 0.05 were considered significant.
For this location, mean extent of injury differed significantly among groups and was greatest for the organized dogfighting group, indicating association of this injury location with organized dogfights.
For this location, mean extent of injury differed significantly among groups and was greatest for the BDLD group, indicating association of this injury location with BDLD fights.
See Table 1 for remainder of key.
Of the injuries for which the extent of injury score differed significantly among the 3 groups according to the ANOVA, 3 were associated with BDLD fights: body surface injuries in the thoracic and lumbar vertebral region, body surface injuries to the lateral thoracic and abdominal region, and fractures of the ribs (Table 2). All other injuries that differed significantly among groups (ie, body surface injuries in 10 other zones and dental injuries) were associated with organized dogfighting.
The patterns of injury based on prevalence data (Table 1) are graphically compared (Figure 2). The locations with the highest prevalence of injury in BDLD fights (n = 160 dogs) were the lateral thoracic and abdominal region (56 [35%]), the dorsal and lateral aspects of the neck (42 [26.3%]), the thoracic and lumbar vertebral region (32 [20%]), the ventral thoracic and abdominal region (27 [16.9%]), and the eye and periorbital region (25 [15.6%]). Fractures of the ribcage were also fairly common (22 [13.8 %]). For dogs used in organized dogfights (n = 62), the body surface zones with the highest prevalence of injury were the thoracic limbs (60 [96.8%]), the dorsal and lateral aspects of the head (58 [93.5%]), the muzzle and oral mucosa (55 [88.7%]), the dorsal and lateral aspects of the neck (45 [72.6%]), and the ventral neck and thoracic region (36 [58.1%]). For MDMD dogs (n = 36), the most common sites of injury were the pinnae (16 [44.4%]), the dorsal and lateral aspects of the neck (15 [41.7 %]), the thoracic limbs (15 [41.7%]), the muzzle and oral mucosa (9 [25%]), the dorsal and lateral aspects of the head (7 [19.4%]), and the pelvic limbs (6 [16.7%]).
Patterns of injury mapped on the basis of prevalence data for 258 dogs in a retrospective study to characterize and compare injuries incurred in spontaneous versus organized dogfights. Shaded areas depict the 5 or 6 body surface zones with the highest prevalence of injury in 160 dogs involved in spontaneous fights with a larger dog (BDLD group; A), 62 dogs that were seized in connection with dogfighting law enforcement raids (organized dogfighting group; B), and 36 medium-sized dogs (body weight, 12 to 42 kg [26.4 to 92.4 lb]) that spontaneously fought with another dog of the same sex and similar size (body weight difference, ≤ 5 kg [11 lb]; MDMD group; C).
Citation: Journal of the American Veterinary Medical Association 251, 12; 10.2460/javma.251.12.1424
Although comparison of the most commonly injured locations for dogs used in organized dogfighting versus those involved in MDMD fighting revealed an overlap in commonly injured regions between the 2 groups, the proportion of dogs with injuries in a given zone varied substantially (Figure 2; Table 1). For example, evaluation of the prevalence data revealed that 8 zones were affected in ≥ 33% of dogs used in organized dogfighting, whereas only 3 zones were affected in ≥ 33% of dogs involved in MDMD fights. In addition, missing, loose, or fractured teeth were identified in 25 of 62 (40.3%) dogs used in organized fighting but in 0 of 36 dogs involved in MDMD fighting.
Discussion
In the present study, subjective and objective measures identified differences in the patterns of injury incurred between spontaneous (BDLD or MDMD) and organized dogfighting. When the prevalence of injuries was compared between organized fighting dogs and medium-sized dogs that spontaneously fought with another dog of the same sex and similar weight, it was clear that organized fighting dogs not only more commonly had injuries to a given area, but also more typically had multiple injuries.
Although it is unlikely that clinicians would encounter difficulty distinguishing injuries incurred through BDLD fights from those resulting from organized dogfighting, the goal of describing a pattern of injury for BDLD fights was to determine whether the methods used in this study would reveal a pattern that corresponded with the frequently observed mechanism of injury and that matched the typical clinical findings in such cases, thus supporting the validity of the method proposed in the present study to determine patterns of injury. Injuries to body surface regions in dogs evaluated after BDLD fights (n = 160) most commonly involved the thoracic and abdominal areas (the lateral aspect [56 {35%}], dorsal aspect [32 {20%}], and ventral aspect [27 {16.9%}]), the dorsal and lateral aspects of the neck (42 [26.3%]), and the eye and periorbital region (25 [15.6%]). In BDLD fights, the larger dog typically grasps the smaller dog around the midsection or by the scruff of the neck, which would be consistent with the high prevalence of body surface injuries in these regions as well as rib fractures. The larger dog also often bites down and shakes the smaller dog, essentially treating the smaller dog as prey or as a toy.13–16 Extrapolation from human studies could support the theory that shaking of the smaller dog could be related to the relatively high prevalence of ocular injury in the BDLD incidents evaluated in the present study; violent shaking may cause intraocular damage because of the increase in intracranial and intraocular venous pressure19 along with the acceleration-deceleration forces associated with whiplash.20 Thus, the pattern of injury described for dogs involved in BDLD fights in the present study was found to correspond with the mechanism of injury and the clinical findings frequently observed on evaluation, thereby supporting the use of this method in describing patterns of injury.
Results of the ANOVA indicated that the injuries that were significantly associated with BDLD fighting were body surface injuries to the lateral thoracic and abdominal region, fractures of the ribcage, and injuries to the thoracic and lumbar vertebral region. The ANOVA also showed that 10 of the 13 body surface zones as well as dental injuries (missing, loose, or fractured teeth) were significantly associated with organized fighting. However, the testing for statistical significance was likely influenced by the tremendous number of injuries that the organized fighting dogs sustained relative to the spontaneous fighting dogs, and highlighting all those regions of the body would not produce a clinically useful pattern of injury. Therefore, prevalence data were used instead to illustrate patterns of injury for each group.
In the present study, dogs that were used in organized fighting most commonly had injuries to the thoracic limbs (60/62 [96.8%]), the dorsal and lateral aspects of the head (58 [93.5%]) and muzzle or oral mucosa (55 [88.7%]), the dorsal and lateral aspects of the neck (45 [72.6%]), and the ventral neck and thoracic region (36 [58.1%]). This pattern of injury was also found to correspond well with what is known about organized dogfighting on the basis of underground literature and advertisements. Individual dogs often preferentially attack certain areas of the other dog's body in a fight. Breeders and handlers frequently describe their dogs according to these behaviors, referring to their dogs by the region of the body that they typically target, and underground fighting literature and advertisements have been found to primarily use terms such as head-dog, chest-dog, and leg-dog,1–4 which correspond to the areas that were found to be most commonly injured in the organized fighting dogs in the present study. Additionally, dogs used for organized fighting are bred and trained to always face the other dog and continue to fight (as turning away may result in a loss), which could be consistent with the high prevalence of injuries to the head and cranial aspects of the body among the organized fighting dogs evaluated in the present study.
In contrast to the organized fighting dogs, the prevalence of injuries in dogs involved in MDMD fights was substantially lower (although the values were not compared statistically). These dogs typically had wounds to the pinnae (16/36 [44.4%]), the dorsal and lateral aspects of the neck (15 [41.7 %]), the thoracic limbs (15 [41.7%]), the muzzle and oral mucosa (9 [25%]), the dorsal and lateral aspects of the head (7 [19.4%]), and the pelvic limbs (6 [16.7%]). In the present study, results regarding dogs involved in MDMD fights differed slightly from what was previously believed, namely that bites in spontaneous dogfights tend to be directed to the scruff, shoulder, and haunches.1,3 This difference could likely have been attributable to the source of MDMD fighting data in the present study (the emergency department of a veterinary teaching hospital that serves as a primary emergency facility and regional referral hospital), as some dogfights may not culminate in a visit to a veterinarian. In 1 study21 of interdog aggression, owners sought veterinary treatment for their dogs after ≥ 1 fight in only 15 of 30 (50%) cases.
Dogs that are brought to a veterinary facility, particularly an emergency hospital, for treatment after a dogfight are presumably those with more severe, or at least more severe-looking, injuries. The scruff, shoulders, and haunches are less vascular than the head and limbs and are also generally covered in longer or thicker fur that might conceal injuries. Therefore, owners could be less likely to notice wounds in these regions or less likely to believe that wounds in these regions require emergency veterinary treatment. This may also have contributed to the unexpected injury distribution patterns in the MDMD group in the present study.
There were several limitations to the present study. Dogs involved in spontaneous fights were selected from a population of dogs evaluated at a veterinary hospital in central Massachusetts, whereas dogs that had been used in organized fighting were mostly obtained from the southern United States. Studies conducted with different populations of dogs may yield different results.
Because the inclusion criteria for each group were strict, every dog that satisfied the criteria was included in the study, so these were convenience samples and not random samples. Therefore, the dogs involved in spontaneous fights in the present study may not have been the best representation of that population. As mentioned, all dogs included in the present study for spontaneous dogfighting had been brought to the emergency room of a primary emergency facility and regional referral hospital, and a previous study21 of interdog aggression noted that only 50% of dogfights even resulted in evaluation by a veterinarian. The study hospital is also open when general practices are not, and it is unclear whether spontaneous dogfights that occur in the evening, at night, or on weekends are substantially different from those that occur at times when the dog may be brought to its primary care veterinarian instead of an emergency facility. Additionally, the inclusion criteria for dogs involved in MDMD fights were chosen to provide the best comparison to the conditions of organized dogfighting, and thus it was necessary that the sex and weight of the other dog in the fight be known. Because of this requirement, each dog involved in MDMD fights had spontaneously fought with another dog in the same household. A study22 of household and nonhousehold aggression between dogs concluded that fights between housemates were more intense and resulted in more serious injury than those in which the dogs did not live in the same house, and this may have affected the patterns of injury seen in the present study, as could the possible intervention of human observers. Body condition score data were not available for many of the dogs involved in MDMD fights, so it is possible that large discrepancies between the BCS of the 2 dogs involved in the fight could have also affected injury patterns.
The dogs in the present study that had been used in organized dogfighting might not have been representative of the population of dogs used in such fights as well. Fighting styles may vary by locale, and the dogs found and seized during law enforcement raids may have included a disproportionate number of winners of previous fights. Considering that winning dogs are less likely to be severely wounded, the injuries observed in the organized fighting dogs in the present study may have been an underrepresentation of the injuries caused by organized dogfighting in general. However, the authors believe that owners would be more likely to seek professional veterinary care for dogs that win fights, so the sample of organized fighting dogs included in the present study may be fairly representative of the cases that a practicing veterinarian might encounter.
Finally, the inclusion criteria for dogs involved in MDMD fights had to be loosened to obtain a sufficiently large sample size. The ideal group for comparison with dogs used in organized fighting would comprise only sexually intact, medium-sized dogs that spontaneously fought with 1 other dog of the same sex and nearly identical weight.
Dogs involved in spontaneous dogfights had different patterns of injury than dogs seized from illegal organized dogfighting operations. Although medium-sized dogs that had fought with another dog of the same sex and similar weight had injuries in some of the same body surface zones as organized fighting dogs, the latter group more commonly had injuries to multiple locations as well as a higher prevalence of injuries, particularly of the thoracic limbs, head, neck, and thorax. Future studies to validate these patterns of injury are warranted. Evidence-based patterns of injury for organized dogfighting will help clinicians to identify dogs harmed in this manner and aid in the prosecution of this crime.
Acknowledgments
Supported by the National Institutes of Health and the Cummings School of Veterinary Medicine at Tufts University.
The authors have no conflicts of interest to declare.
Presented as an oral presentation at the International Veterinary Forensic Sciences Association Conference, Orlando, Fla, May 2015, and as a poster at the Merial-NIH Veterinary Scholars Symposium, Cornell University, Ithaca, NY, August 2014.
The authors thank Dr. Randall Lockwood for his guidance in the preparation of the manuscript.
ABBREVIATIONS
| BCS | Body condition score |
| BDLD | Big dog–little dog |
| MDMD | Medium dog–medium dog |
Footnotes
SPSS Statistics, version 22, IBM Corp, Armonk, NY.
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