This blog post will discuss dog bites in Portugal, with a primary focus on those aimed at children. While doing so, triggers leading to aggression in dogs, as well as the different types of aggressive behaviors dogs may display. Furthermore, the role of pain as it relates to aggressive behavior will be examined. Additionally, assessment and prevention of this particular issue will be highlighted.
Child-directed dog aggression is likely to be any parent’s worst nightmare, in addition to being a potentially traumatic event for the child involved. While allowing children to interact with dogs, whether in the home or elsewhere, can be a wonderful experience, such interactions do come with potential risks, including being bitten.
Only a small number of studies investigating dog bites exist in Portugal (Fragoso et al., 2022, p. 20). According to one report, there were 1460 dog attacks in Portugal in 2020, approximately four per day (Expresso, 2021). Fragoso et al. (2022) conducted research on dog bite incidents, including those to children, as well as their outcomes in a study totaling 729 dogs. The majority of dog bite recipients were female (78.2%); 34.2% were younger than 18 years of age, and 58.1% of the bites were directed towards the upper extremities (Fragoso et al., 2022, p. 21). In 78.1% of cases, the bites resulted in no injuries or minor injuries, and among those that required medical care, 18.6% required surgery (Fragoso et al., 2022, p. 21). Furthermore, 87.2% were single bites, and none of the multi-bite incidents were injury-free (Fragoso et al., 2022, pp. 21-22). In 78.7% of incidents, the dog was familiar with the person, with 45.1% of bites being directed towards their guardian (Fragoso et al., 2022, pp. 21-22). Children under the age of 12 were more susceptible to head injuries compared to other age groups, while in children below the age of two, no injury-free or major injury incidents were reported (Fragoso et al., 2022, p. 25). Additionally, only 3.2% of the total number of episodes were reported to the authorities (Fragoso et al., 2022, p. 24). This would indicate that the majority of dog bites are not reported, and thus, do not appear in bite statistics. As far as the higher number of head injuries in children younger than 12 years of age is concerned, this could be due to the difference in height between children and adults, as well as differences in motor ability (Fragoso et al., 2022, p. 25).
While the majority of bites in this study, including those to children, caused no injury or only minor injuries, children, potentially due to their height and motor abilities, may be particularly susceptible to being on the receiving end of a bite. Furthermore, while severe bites are less common, they can have a significant negative impact on the recipient and those around them (Fragoso et al., 2022, p. 25). Additionally, of the bites that required medical attention, including the aforementioned 18.6% that required surgery, antibiotic treatment was the most common medical intervention (Fragoso et al., 2022, p. 22). Although children in the study were more likely to sustain head injuries compared to other age groups, it is important to acknowledge that those incidents do not necessarily occur due to the size of the child (Meints, 2017, p. 392). Rather, young children, especially those aged two and three years of age, display more intrusive facial proximity behaviors, especially with novel or moving objects, which could trigger a bite to the face if exhibited toward a dog (Meints, 2017, p. 393). This is in contrast to what was suggested by the authors of the dog bite study in Portugal.
While different definitions of what constitutes aggression exist, aggressive behaviors, including growling, snarling, snapping, and biting, can be defined as attacks, attempted attacks, or threats of attack directed at an individual to escape or access certain reinforcers (O’Heare, 2017, p. 33). Except for predatory aggression, which manifests in the SEEKING system, aggressive behaviors are rooted in the RAGE system (Panksepp & Biven, 2012, p. 202). Using contingency analysis to identify the antecedent(s), e.g, stranger approaches, behavior, dog growls, and maintaining consequence(s), stranger moves away (negative reinforcement) can explain when and why the dog displays aggression (O’Heare, 2017, p. 138).
Conflict aggression, previously labeled as dominance aggression, is a form of owner-directed aggression during which the dog experiences competing states of motivation, and when they become frustrated about the inability to perform certain behaviors (Dinwoodie et al., 2021, p. 47; Landsberg et al., 2013, p. 303). These dogs are typically fearful or anxious, and due to inconsistent caretaker signals or actions, learn to display aggression to end the interaction (Landsberg et al., 2013, 303). Physical punishment or confrontational training methods are a risk factor in human-directed aggression (Howell et al., 2025, p. 12). Resource guarding, also known as possessive aggression, is a common behavior in dogs (Landsberg et al., 2013, 305). This is a normal behavior, which can become maladaptive; guarded items can include things such as food, toys, food bowls, novel or stolen objects, people, and the behavior is accompanied by physiological arousal like pupil dilation or a tense body posture (Landsberg et al., 2013, 305). Fear-based aggression is elicited by a fear-inducing stimulus, such as other dogs, people, or cars, which can trigger an aggressive behavioral response (Landsberg et al., 2013, 305). Fear is an underlying emotion in many forms of aggression, and this may stem from inadequate socialization and habituation, genetics, traumatic events, and learning experiences (Landsberg et al., 2013, 305). Dogs may display withdrawal behaviors, as well as passive avoidance, such as looking away, or active avoidance, like escaping or hiding (Overall, 2013, p. 183). Territorial aggression is identified by location, such as the dog’s home, yard, or car, and is directed toward unfamiliar people or animals (Landsberg et al., 2013, p. 310; Overall, 2013, p. 191). Protective aggression can be seen when a dog displays behaviors like growling, barking, lunging, when an individual approaches a family member, whether human or animal, which the dog perceives as threatening (Landsberg et al., 2013, p. 310; Overall, 2013, p. 191). It is not uncommon for dogs to display both territorial aggression and protective aggression, and for certain breeds, there may be a hereditary predisposition (Landsberg et al., 2013, p. 310).
Predatory aggression is a normal instinct in dogs; however, the behavior can become maladaptive when directed toward joggers, children playing/running, domestic animals, moving vehicles, or cyclists (Landsberg et al., 2013, p. 313). Predatory behavior can include stalking, chasing, biting, or killing the target (Landsberg et al., 2013, p. 313). The aforementioned SEEKING system is active during such displays, as opposed to RAGE, so labeling this as aggression, despite the fact that the recipient would perceive it as such, could be controversial. As such, maladaptive predatory behavior might be a more appropriate term. Play aggression is often seen in play solicitation; here, the dog may use barking, growling, or biting to get people to play (Overall, 2013, p. 181). If the dog has poor bite inhibition or gets too aroused, this can become problematic for the family or visitors (Landsberg et al., 2013, p. 315). Maternal aggression can be directed toward people or other animals by a bitch who is pregnant, has recently given birth, or is experiencing pseudocyesis (Landsberg et al., 2013, p. 318; Overall, 2013, pp. 179-180). The behavioral intensity can vary greatly between dogs, with some individuals growling, while others may bite and injure with little warning (Landsberg et al., 2013, p. 318). Redirected aggression occurs when aggressive behavior is directed toward a person, animal, or object that is not the stimulus for the initial response; redirection is a result of frustration related to other forms of aggression (Landsberg et al., 2013, p. 319). The primary motivation for the aggressive display could be territorial, protective, or fear-based, whereas the redirected aggression is secondary, and could be aimed at another dog in the home that happens to walk by while the aggressor is frustrated or interrupted from reaching their primary target (Landsberg et al., 2013, p. 319; Overall, 2013, p. 203). Intrahousehold dog aggression is most commonly related to resources, arousal and excitement, owner proximity and attention, as well as tight spaces (Feltes et al., 2020, p. 356; Landsberg et al., 2013, p. 321). Pathophysiological aggression stems from underlying physiological or physical abnormalities (Landsberg et al., 2013, p. 324). These could include abnormal neurotransmitter activity, neoplasia, metabolic disorders, trauma, or toxins, among others (Landsberg et al., 2013, p. 324).
Another antecedent to consider when it comes to aggression is pain. Pain-induced aggression, as well as irritable aggression, which might not cause pain, but the medical condition may increase irritability, resulting in aggressive behaviors, constitute another aggression category in dogs (Landsberg et al., 2013, p. 314). Pain can cause an individual to feel vulnerable, may create an association between the dog or person they attempt to greet and a pain response, and can also lead to resource guarding behaviors, as well as protection of certain body parts (Lindley, 2021, p. 50; Overall, 2013, p. 187). A dog in pain may also choose to avoid interactions if contact with a familiar person involves hugging or cuddling, which could exacerbate pain (Mills et al., 2020, p. 14). Pain can also play a role in fear-based aggression. For example, a dog may become fearful of different noises, as they tense up in response, causing them more pain (Mills et al., 2020, p. 14). If a scary noise or another stimulus becomes associated with said noise, and the dog is unable to escape, this could lead to aggressive behavior. As such, it is vital to rule out pain when working with aggression cases. Finally, idiopathic aggression is diagnosed when the aggressive behaviors appear unpredictable, with stimuli that do not fit any other category, and where no physical or physiological conditions can be found (Overall, 2013, p. 222).
As can be seen, several antecedents can evoke aggressive behavior in canines. Furthermore, aggression can also be divided into defensive and offensive aggression. Defensive aggression will typically involve a lower body posture, ears back, lowered tail, and looking away from the trigger; conversely, offensive aggression includes a taller body posture, hard stare, lunging, barking, and chasing the target (Siracusa, 2021, p. 193). A conflicted dog’s body language and behavior may also vacillate between the two (Siracusa, 2021, p. 193).
In a study on 111 children who were bitten by dogs, 31% were younger than six years old, and 69% were between 6 and 17 years of age (Reisner et al., 2007, p. 348). Familiar children were most commonly bitten due to resource guarding, followed by interacting with the dog in the form of hugging, petting, or bending over the dog; unfamiliar children were most commonly bitten upon entering the dog’s territory (Reisner et al., 2007, p. 348). Children below the age of six were more likely to be bitten due to resource guarding, stepping on, or falling on top of the dog (Reisner et al., 2007, p. 348). Medical conditions were identified or suspected in 50% of the dogs, including orthopedic and dermatologic conditions (Reisner et al., 2007, p. 350).
Given the aforementioned propensity of young children to utilize intrusive inspection behavior, and the high prevalence of bites due to resource guarding and interaction, parental supervision of the child and dog with the ability to intervene at all times is essential (Starling & McGreevy, 2017, p. 385). Furthermore, the supervising adult must be sufficiently proficient in dog body language to identify situations that may potentially escalate (Starling & McGreevy, 2017, p. 385). Thus, it is crucial to educate children and parents on dog body language that signals the dog is uncomfortable with the situation to avoid injury or distress (Meints, 2017, p. 398). Given the prevalence of incidents involving resource guarding, children need to be taught to avoid approaching the dog’s bed, food bowl, or removing objects from the dog (O’Heare, 2017, p. 98). Allowing the dog to have a safe space away from children such as their bed or crate, can allow them a place to escape to if needed (Siracusa, 2021, p. 195) For a fearful dog, a child starting to crawl or walk can be a trigger, and the child might approach the dog and corner it, which can remove the dog’s flight option (Landsberg et al., 2013, p. 308). Ensuring safety through the use of leashes, muzzles, and gates is important to prevent incidents, even if the dog has never bitten (Landsberg et al., 2013, p. 304; O’Heare, 2017, p. 99). Furthermore, for people adopting puppies, it is important to expose them to children and have reinforcing interactions with them during the 7-12 week period (O’Heare, 2017, p. 92). The elements combined should prevent issues from arising in many cases.
For a dog that’s displaying aggression towards children, rehoming the dog to a child-free home can be a good option (O’Heare, 2017, p. 174). Where this is not a possibility, the aforementioned safety and management recommendations and body language education should be followed, preferably with at least two layers of separation between the dog and child at all times. A behavior professional should be consulted, and a veterinary visit should be scheduled. In combination with management, counterconditioning, systemic desensitization, or differential reinforcement, among other options, may be implemented (Landsberg et al., 2013, p. 309; O’Heare, 2017, pp. 198-199). In some cases, psychoactive medication prescribed by a veterinarian or veterinary behaviorist to reduce excessive arousal and assist in behavior modification is beneficial (Siracusa, 2021, p. 196). Furthermore, while behavior modification should focus on helping the dog feel more relaxed around children, physical interaction may not be a realistic goal (Landsberg et al., 2013, p. 309).
In the case of a three-year-old neutered Border Collie mix who recently started chasing, barking, and growling toward the household toddler when she began walking, and where rehoming is not an option, a vet check is a first step. With a clean bill of health, behavioral history reveals limited information about his exposure to children prior to adoption at one year of age. Behavioral history reveals a propensity to chase bicycles, as well as controlling the movement of unfamiliar visitors when they get up from their chair; herding breeds can be more prone to displaying such behaviors (Brophey, 2018, p. 214). Furthermore, the dog has recently reached social maturity, which is an age at which many undesirable behaviors develop or fully surface (Overall, 2013, p. 197). Several factors may thus be at play, including maladaptive predatory behavior, controlling the toddler’s movements, and a potential lack of exposure to children during puppyhood. Regardless of the exact behavioral label, functional analysis, whereby the antecedents, behaviors, and reinforcing consequences are identified reveal that when the child starts walking, the dog begins chasing the child, and proceeds to barking and growling when the child continues to walk, and stops when the toddler is picked up and removed by a parent e.g. stops walking (O’Heare, 2017, p. 138). Despite the lack of air snapping or biting, an initial recommendation includes two layers of separation at all times in the form of a house leash and gates, while a muzzle is being acclimated via respondent conditioning by pairing it with an unconditioned stimulus in the form of food, until the muzzle comes to elicit a conditioned response (O’Heare, 2017, p. 85). Additionally, the child and dog should always be supervised, and a muzzle can allow for more freedom when combined with the leash or gate. Body language education to help notice the early signs of aggression, and redirect the dog’s attention, including a hard stare and a tense body, was also described to the client. Ensuring sufficient enrichment for the dog in the form of social interactions, physical exercise, object play and sensory exploration, in addition to breed-specific herding outlets directed at toys and food to ensure the dog’s needs are met, is also implemented (Landsberg et al., 2013, p. 91). Going over the variables and realistic goal setting and expectations with the family is important, as unrealistic goals or the expectation of fast results with little effort, reduce the likelihood of a successful outcome (O’Heare, 2017, p. 143). When questioned on this, the family indicated they were happy to comply with the recommendations, were willing to put in the effort needed, and were aware that some degree of management may be necessary throughout the dog’s life. Finally, a graded differential added reinforcement of alternative, and eventually, incompatible behavior, procedure, which aims to put the target (aggressive) behavior on an extinction schedule, and reinforcing a replacement behavior by means of graded errorless exposure was recommended (O’Heare, 2017, p. 197). This involves reinforcing the new behavior, in this case calmly looking at, and eventually disengaging from, the walking toddler, along several variables including distance, duration, and intensity of the toddler, e.g, orientation and animation of the child (O’Heare, 2017, pp. 193, 197). As the dog did not display fearful behavior around the child and was otherwise well adjusted to his environment with no reported or observed anxiety issues, no adjunctive measures, such as veterinary-prescribed psychoactive medication or supplements, were discussed.
In conclusion, while limited data on dog bites to children exist in Portugal, available research does highlight children being more vulnerable to certain types of bites and with a higher prevalence of head injuries. Furthermore, dogs display aggressive behaviors for a wide variety of reasons, and familiar children are particularly susceptible to bites due to resource guarding, while unfamiliar children may get bitten due to territorial aggression. As pain is a common component of aggression cases, a medical check is advisable. Additionally, education on dog body language and dog bite prevention is essential for adults and children sharing their lives with dogs.
References:
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