Article

Factors linked to dominance aggression in dogs

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Abstract

The aim of this study was to determine factors that might be linked to dominance aggression in pet dogs. Our results show that possession aggression is the first manifestation of dominance aggression and its basic form. Modifiable and non-modifiable factors that are associated with higher levels of dominance aggression and depend on the owner include first time ownership, a lack of obedience training, the owner not being the main obedience trainer, spoiling the dog, not using physical punishment, acquisition as a present, as a pet, impulsively, or to guard and spaying female dogs. Modifiable factors have the greatest influence on dominance aggression in dogs. Dog-dependent factors (gender, breed, age, size and coat color) are fewer than owner dependent factors. There was an association between certain dog behaviour patterns and higher level of dominance aggression.

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... Dogs living in rural areas have been found to more likely behave aggressively toward strangers than dogs living in cities 14 . Furthermore, time spent with the owner 14 , and owner's dog experience 14,[20][21][22] have been associated with aggressiveness, and early weaning has been suggested to increase the probability of aggressive behaviour 23 . We studied the factors associated with canine aggressive behaviour toward people (strangers and family members) in over 9000 Finnish purebred pet dogs with multiple logistic regression and we also formed a priori hypotheses based on previous literature. ...
... This large-scale survey study of over 9000 pet dogs suggests that aggressive behaviour toward people is affected by behaviour, demography, and environment. The studied factors daily time spent alone, and weaning age were novel, and factors living environment, family size, dogs in the family, dog experience, daily exercise, have previously been studied only in few articles 14,15,[20][21][22] . Dogs showing aggressive behaviour were more often fearful, smallsized, males, owner's first dogs and the only dogs in the family. ...
... We hypothesised that older dogs are more aggressive than younger dogs 10,14,15 , that male dogs are more aggressive than female dogs 1,14 , and that small sized dogs are more aggressive than larger dogs 17 . We also hypothesised that highly fearful dogs are more aggressive than non-fearful individuals 11,13 , that dogs living in households without other dogs are more aggressive than dogs living with other dogs 20 , that dogs living in rural areas are more aggressive than ones living in cities 14 , that early weaned dogs are more aggressive than late weaned dogs 23 , and that dogs living with unexperienced owners have a higher probability of aggressive behaviour [20][21][22] . We also hypothesised that Lagotto Romagnolo, Chihuahua, German Shepherd Dog, and Miniature Schnauzer are more aggressive breeds than Golden Retriever and Labrador Retriever 11,14,19,20 . ...
Article
Full-text available
Aggressive behaviour is an unwanted and serious problem in pet dogs, negatively influencing canine welfare, management and public acceptance. We aimed to identify demographic and environmental factors associated with aggressive behaviour toward people in Finnish purebred pet dogs. We collected behavioural data from 13,715 dogs with an owner-completed online questionnaire. Here we used a dataset of 9270 dogs which included 1791 dogs with frequent aggressive behaviour toward people and 7479 dogs without aggressive behaviour toward people. We studied the effect of several explanatory variables on aggressive behaviour with multiple logistic regression. Several factors increased the probability of aggressive behaviour toward people: older age, being male, fearfulness, small body size, lack of conspecific company, and being the owner’s first dog. The probability of aggressive behaviour also differed between breeds. These results replicate previous studies and suggest that improvements in the owner education and breeding practices could alleviate aggressive behaviour toward people while genetic studies could reveal associated hereditary factors.
... Other than intrinsic factors, evidence regarding the importance of environmental variables to canine aggression is also gradually accumulating. Environmental factors such as owners' characteristics (e.g., age, sex, level of education, experience with dogs, personality: Jagoe and Serpell, 1996;Serpell, 1997a, 1997b;Pé rez-Guisado and Muñ oz-Serrano, 2009), living situation (e.g., area of residence, housing type, other pets in the household, size of household: Takeuchi et al., 2001;Messam et al., 2008;Pé rez-Guisado and Muñ oz-Serrano, 2009), interaction with the owners (e.g., age acquired, time/frequency interacting with the owners, methods of reprimand: Serpell, 1997a, 1997b;Tami et al., 2008;Pé rez-Guisado and Muñ oz-Serrano, 2009) have all been reported to correlate with a dog's aggressiveness. These studies suggest that aggression in household dogs could be reduced by improving their environment, despite the importance of the dogs' intrinsic characteristics (breed, sex, age, etc.). ...
... Other than intrinsic factors, evidence regarding the importance of environmental variables to canine aggression is also gradually accumulating. Environmental factors such as owners' characteristics (e.g., age, sex, level of education, experience with dogs, personality: Jagoe and Serpell, 1996;Serpell, 1997a, 1997b;Pé rez-Guisado and Muñ oz-Serrano, 2009), living situation (e.g., area of residence, housing type, other pets in the household, size of household: Takeuchi et al., 2001;Messam et al., 2008;Pé rez-Guisado and Muñ oz-Serrano, 2009), interaction with the owners (e.g., age acquired, time/frequency interacting with the owners, methods of reprimand: Serpell, 1997a, 1997b;Tami et al., 2008;Pé rez-Guisado and Muñ oz-Serrano, 2009) have all been reported to correlate with a dog's aggressiveness. These studies suggest that aggression in household dogs could be reduced by improving their environment, despite the importance of the dogs' intrinsic characteristics (breed, sex, age, etc.). ...
... Other than intrinsic factors, evidence regarding the importance of environmental variables to canine aggression is also gradually accumulating. Environmental factors such as owners' characteristics (e.g., age, sex, level of education, experience with dogs, personality: Jagoe and Serpell, 1996;Serpell, 1997a, 1997b;Pé rez-Guisado and Muñ oz-Serrano, 2009), living situation (e.g., area of residence, housing type, other pets in the household, size of household: Takeuchi et al., 2001;Messam et al., 2008;Pé rez-Guisado and Muñ oz-Serrano, 2009), interaction with the owners (e.g., age acquired, time/frequency interacting with the owners, methods of reprimand: Serpell, 1997a, 1997b;Tami et al., 2008;Pé rez-Guisado and Muñ oz-Serrano, 2009) have all been reported to correlate with a dog's aggressiveness. These studies suggest that aggression in household dogs could be reduced by improving their environment, despite the importance of the dogs' intrinsic characteristics (breed, sex, age, etc.). ...
Article
This study used The Canine Behavioral Assessment and Research Questionnaire (C-BARQ) and regression models to explore the relative importance of dog and owner characteristics, living environment and owner–dog interaction to household dogs’ aggressiveness towards strangers, owners and other dogs. Exploratory factor analysis revealed 10 interpretable factors from the Chinese translation of C-BARQ: stranger-directed aggression, owner-directed aggression, dog-directed aggression, social fear, nonsocial fear, separation-related behavior, attachment or attention-seeking behavior, trainability, excitability and pain sensitivity. The factor structure of our study largely resembled that reported in Hsu and Serpell (2003) and van den Berg et al. (2006; Dutch translation of C-BARQ). All factors of the translated C-BARQ have adequate reliability (Cronbach α: 0.74–0.93) and are thus suitable for measuring temperament traits in Taiwan's pet dogs. Intrinsic and environmental variables important to the three aggression subscales were not entirely the same, but breed (P≤0.020) and physical punishment (P≤0.053) had significant relationships with all of them. Golden Retriever scored the lowest while dogs subjected to physical reprimands scored significantly higher on aggression subscales. In addition, higher scores on stranger-directed aggression were associated (P≤0.027) with living in rural areas, in houses with yard space and with more household members and being acquired either as puppies or for guarding purposes. Higher scores on owner-directed aggression were associated (P≤0.040) with male and older dogs, being neutered/spayed, having female owners, fewer other dogs in the household and being kept outside the house. Higher scores on dog-directed aggression, on the other hand, were associated (P≤0.050) with living in houses with either yard space or more household members and with spending less time with owners. Stranger- and dog-directed aggression had more important intrinsic and environmental variables common to them than did owner-directed aggression, which suggests that aggression towards owners may be regulated by different mechanisms from aggression towards strangers and other dogs. Although no causal relationship between dog aggression and environmental variables can be implied from observational studies, the results of this and other studies lend support to the possibility of reducing dogs’ aggressive responses through proper management by owners.
... termed "dominance aggression" [38,39] whereby the owner [39,40], the dog's living conditions and the interactions with the owner [40] had the greatest influence on affect control aggression. Other authors, in turn, did not associate neutering with aggression against people of the same household [12], against other people [12], or against other dogs [1,12]. ...
... termed "dominance aggression" [38,39] whereby the owner [39,40], the dog's living conditions and the interactions with the owner [40] had the greatest influence on affect control aggression. Other authors, in turn, did not associate neutering with aggression against people of the same household [12], against other people [12], or against other dogs [1,12]. ...
... Furthermore, dog breeds were hypothesised to differ, with Chihuahuas, German Shepherd Dogs, Lagotto Romagnolos, and Miniature Schnauzers being more aggressive than Golden and Labrador Retrievers (Duffy et al., 2008;Hsu & Sun, 2010;Serpell & Duffy, 2016;Tiira et al., 2016). Other hypotheses included assumptions that fearful dogs would be more aggressive than non-fearful dogs (Haverbeke et al., 2009), that dogs living as an only dog would be more aggressive than dogs living with other dogs (Serpell & Duffy, 2016), and that dogs belonging to first-time dog owners would be more aggressive than dogs of experienced owners (Jagoe & Serpell, 1996;Pérez-Guisado & Muños-Serrano, 2009;Serpell & Duffy, 2016). ...
Thesis
Full-text available
Behavioural traits are complex, influenced by multiple genes and environmental factors and they can also affect the health and welfare of individuals. Behaviour is equally important for companion animals, cats and dogs. Furthermore, some of their behavioural traits resemble human psychiatric diseases. Despite behaviour’s importance, its biological background is still poorly known in these animals. This thesis examines the complexity of behaviour by studying the genetic and environmental factors influencing behaviour, as well as behavioural intercorrelations simultaneously in two companion animal species: the dog and the cat. This comparative perspective may reveal insights into the background of behaviour that could also be generalized to human behaviour. Specifically, this thesis aims to study 1) breed differences of dogs and cats and heritability of behaviour in cats, 2) behaviour correlations in both species, and 3) environmental factors influencing aggression in dogs and multiple behavioural traits in cats. Behavioural and background data was collected from the dog and cat owners through online questionnaires. In both species, the frequency of fear, aggression, and abnormal repetitive behaviour was examined. Sociability and level of activity was also examined in cats and impulsivity/inattention in dogs. Large datasets of 13 715 dogs and 5726 cats were collected and analysed with different methods, including multiple logistic regression for the environmental factors of behaviour and Bayesian multivariate model for heritability analyses. The results of this thesis show that both dog and cat breeds differ in behaviour, that behaviour is heritable, that many behavioural traits are correlated, and that many environmental factors are associated with behavioural traits. Heritability estimates varied between 0.40 and 0.53 for all behavioural traits and breeds. Especially fear and aggression correlated strongly and these traits were also associated with abnormal repetitive behaviour in both species. Social environment in both early life and at the time of answering was associated with lower incidence of aggression and abnormal repetitive behaviour. The results closely paralleled in both companion animal species and showed some parallels to human psychiatry as well. This finding indicates that the biological background of behaviour is similar in dogs and cats, and likely in humans as well. The findings of this thesis had great scientific and practical impact, as, for example, regulations for separating a kitten from its mother was adapted accordingly.
... The most frequent canine behaviors considered to be problematic are usually characterized as anxiety (Flannigan & Dodman, 2001), aggressiveness towards people such as biting, growling (Perez-Guisado & Munoz-Serrano, 2009), and excessive vocalizations (Wells & Hepper, 2000;Ramazan, Day, & Phillips, 2016). The expression of such problematic behaviors can be associated with specific interactions between the dog and keeper, as an excessive attachment of a dog with his/her keeper can change their behaviors in an undesirable way (Guy et al., 2001;Jagoe & Serpell, 1996;Storengen, Boge, Strom, Loberg, & Lingaas, 2014). ...
Article
This study was used to evaluate whether the proximity of dogs to their human companions during sleep is associated with common problematic behaviors in canines, such as destroying objects, vocalizing excessively, urinating/defecating in inappropriate places (all when dogs are alone at home), and aggressive threats (growling or barking) and acts (biting) toward people. Over 60,000 dog keepers answered an online questionnaire that addressed where their dogs slept at night and the frequency with which they exhibited such behaviors. Except urinating/defecating in inappropriate places and biting people, other problematic behaviors were less frequent in dogs who slept inside the house. We conclude that dogs sleeping indoors (that is, closer to their keepers) less frequently exhibit aggressive threats and problematic behaviors that are commonly associated with separation anxiety.
... However, only two entire females were collared during the present study and further research is required to determine whether this effect is consistent at a population level. In contrast, dominance and territorial aggression was found to be more common in male dogs [41,42], which may result in fewer contacts due to avoidance behaviour exhibited by subordinate animals. ...
Article
Full-text available
Free-roaming dogs (Canis familiaris) are common worldwide, often maintaining diseases of domestic pets and wildlife. Management of these dogs is difficult and often involves capture, treatment, neutering and release. Information on the effects of sex and reproductive state on intraspecific contacts and disease transmission is currently lacking, but is vital to improving strategic management of their populations. We assessed the effects of sex and reproductive state on short-term activity patterns and contact rates of free-roaming dogs living in an Australian Indigenous community. Population, social group sizes and rates of contact were estimated from structured observations along walked transects. Simultaneously, GPS telemetry collars were used to track dogs' movements and to quantify the frequency of contacts between individual animals. We estimated that the community's dog population was 326±52, with only 9.8±2.5% confined to a house yard. Short-term activity ranges of dogs varied from 9.2 to 133.7 ha, with males ranging over significantly larger areas than females. Contacts between two or more dogs occurred frequently, with entire females and neutered males accumulating significantly more contacts than spayed females or entire males. This indicates that sex and reproductive status are potentially important to epidemiology, but the effect of these differential contact rates on disease transmission requires further investigation. The observed combination of unrestrained dogs and high contact rates suggest that contagious disease would likely spread rapidly through the population. Pro-active management of dog populations and targeted education programs could help reduce the risks associated with disease spread.
... Given the higher probability of usurpation due to the lower availability of cavities for female intruders in this population, females with low T levels may be forced to stay more time closer to the nest-box to confront conspecific intruders. It is a common observation in other species that the more dominant individuals are not necessarily the most aggressive ones (Beaugrand & Zayan 1985;Bekoff 1977;Higley 2003;Pérez-Guisado & Muñoz-Serrano 2009). ...
... Given the higher probability of usurpation due to the lower availability of cavities for female intruders in this population, females with low T levels may be forced to stay more time closer to the nest box to confront conspecific intruders. It is a common observation in other species that the more dominant individuals are not necessarily the most aggressive ones (Bekoff 1977;Beaugrand & Zayan 1985;Higley 2003;P erez-Guisado & Muñoz-Serrano 2009). Aggressiveness as measured in some studies may not relate to the capacity to dominate other individuals, so we should try to relate this capacity to T levels in further studies. ...
Article
Nesting holes are a scarce resource for obligated cavity nesting birds and an important selective force for the evolution of aggressive female behaviours, which may be mediated by testosterone (T) levels. It is known that during periods of intense intrasexual competition such as initial breeding stages, females are highly aggressive towards intruding females. Here, we studied the implications of T levels for female-female competition by comparing levels of aggressiveness towards simulated female intruders (decoys) in two populations of the pied flycatcher (Ficedula hypoleuca) with a marked difference in breeding density. To this end, we exposed free-living females to simulated territorial intrusions during 30 min when nest construction was almost complete. T levels of females were measured at the beginning of incubation under the assumption they are positively associated with T levels during nest building. We also related aggressiveness to T levels in both populations. Furthermore, we aimed at detecting if variation of T levels may explain female incubation attendance. Females showed higher T levels in the populations where pied flycatchers were exposed to a higher likelihood of conspecific interactions (high breeding density) than in the population with low breeding density. Female territorial presence, vigilance at the nest-box and proximity to decoys were negatively related to circulating T levels in the high density population, but not in the low density population. Differences in T levels between populations did not result in differences in female incubation attendance, but T levels were negatively related to the incubation attendance in females from the population showing high T levels. In our populations, T levels in females prior to laying reflect the need to defend nesting cavities which is higher at high breeding density and in subdominant females. High T levels are costly in terms of incubation attendance.
... Isso ocorre, provavelmente, porque o resultado imediato do teste não prevê a reação deste filhote à forma com que será criado até a vida adulta nem a relação desse filhote com o proprietário, idéia já sugerida por Campbell (1972) ao divulgar o teste comportamental para seleção de filhotes. Corroborando esta idéia, um estudo espanhol (Pérez- Guisado e Serrano, 2009) identificou alguns fatores associados aos casos de agressão por dominância como: o fato do cão ter alimento a vontade; cães que caminham ou interagem pouco com seus proprietários; cães sem um processo de educação básica; e proprietários que tem um cão pela primeira vez. Todos esses detalhes devem ser considerados na seleção dos filhotes, associado ao teste, para assim prevenir problemas de agressividade por dominância nos cães, principalmente raças envolvidas no presente estudo por serem populares no Brasil. ...
Article
Full-text available
Campbell, em 1972, desenvolveu um teste para seleção de filhotes de cães, com objetivo de determinar seu grau de dominância para direcioná-los para uma atividade ou família compatível. No presente estudo, o teste de Campbell, tal como ficou conhecido, foi aplicado em filhotes de cinco raças para avaliar possíveis diferenças comportamentais. Os filhotes (138 Labrador; 71 Rottweiler, 31 Bull Terrier, 13 Cocker Spaniel Inglês e 12 Pit Bull), com idade entre seis e oito semanas foram testados em seus canis de origem. Os resultados foram analisados estatisticamente através do teste de Kruskal-Wallis e a comparação entre os pares pelo teste de Mann-Whitney. Os filhotes de Labrador mostraram maior pontuação total no teste comparado aos de Rottweiler (P=0,02) e Bull Terrier (P=0,01). Com esses resultados pode-se caracterizar uma maior atração do filhote de Labrador ou uma maior independência do filhote de Rottweiler e de Bull Terrier em relação ao ser humano, considerando que as etapas do Teste de Campbell que mais evidenciaram a diferença foram àquelas em que o filhote tem que demonstrar interesse pelo examinador.
... According to this scenario, we could expect the size of white plumage patches to relate to competitive potential and social rank. However, it has been observed in other species that the more dominant individuals do not need to be aggressive to impose their status (Higley 2003, Pérez-Guisado and Muñoz-Serrano 2009, Nicol 2015. ...
Article
Full-text available
In a substantial number of species, females show some development of secondary sexual characters. These traits can function as signals of individual phenotypic or genetic qualities and status to conspecifics. Individuals may benefit potentially from expressing signals or badges of status if they are reliable and honest signals of individual quality. In many species, badge sizes have been shown to correlate with dominance rank, which may be mediated by testosterone (T) levels. Here, we explored geographic variation in the size and properties of the white wing patch of female pied flycatchers Ficedula hypoleuca and its relation to circulating T levels in three populations (two southern populations in central Spain and a northern population in Finland). Furthermore, we aimed at detecting if the size of the white wing patch and its ultraviolet (UV) reflectance indicate individual quality. We found that females in Spain had larger, brighter and more UV reflecting wing patches than those in Finland. Females with higher UV reflectance and larger primary white patches bred earlier. Younger females and females with larger primary white wing patches showed higher T levels. In contrast, higher values of UV reflectance in feathers from these patches were associated with low T levels. Despite genetic differentiation and differences in trait expression between populations, female pied flycatchers from different populations may converge and use the size of white wing patches to signal their T levels and thereby their social dominance.
... Some still argue that dogs usually avoid eye contact when fearful [41], but there are evidences that, in a friendly and cooperative situation between dogs and owners, eye contact does not pose a threat, but instead, it would facilitate communication [42]. In fact, when humans communicate with dogs, they generally use visual signals that provide information regarding the focus of attention; a recent study found that dogs displayed more attention-getting behaviors when the owners were gazing directly at them than when the owners averted their gazes [43]. ...
Article
Full-text available
Dogs discriminate human direction of attention cues, such as body, gaze, head and eye orientation, in several circumstances. Eye contact particularly seems to provide information on human readiness to communicate; when there is such an ostensive cue, dogs tend to follow human communicative gestures more often. However, little is known about how such cues influence the production of communicative signals (e.g. gaze alternation and sustained gaze) in dogs. In the current study, in order to get an unreachable food, dogs needed to communicate with their owners in several conditions that differ according to the direction of owners' visual cues, namely gaze, head, eyes, and availability to make eye contact. Results provided evidence that pet dogs did not rely on details of owners' direction of visual attention. Instead, they relied on the whole combination of visual cues and especially on the owners' availability to make eye contact. Dogs increased visual communicative behaviors when they established eye contact with their owners, a different strategy compared to apes and baboons, that intensify vocalizations and gestures when human is not visually attending. The difference in strategy is possibly due to distinct status: domesticated vs wild. Results are discussed taking into account the ecological relevance of the task since pet dogs live in human environment and face similar situations on a daily basis during their lives.
... Once an agreement is reached, the interaction may then form the basis for future encounters, avoiding the need for ongoing disputes. However, if anything changes, such as either dog's physical health, mood or the value placed on the bone, then this The Veterinary Nurse | April 2017, Volume 8 No 3 © 2017 MA Healthcare Ltd and 'dominance hierarchies' , whether patters of 'dominant' and 'submissive' behaviour imply a dominance hierarchy, interpretation of the motivation for aggressive behaviour, and whether this can be attributed to an attempt to elevate rank, as well as the methodology for studying the subject, and how data collected is interpreted (Bradshaw et al, 2009;Perez-Guisado and Munoz-Serrano, 2009;Schilder et al, 2014;Trisko and Smuts, 2015;Westgarth, 2016). ...
Article
Aggression is the canine behaviour most likely to lead to relinquishment or euthanasia. Understanding how dogs socially interact and manage conflict is therefore of particular importance to veterinary professionals. Traditional approaches to the prevention and management of canine aggression advocated owners assert themselves as ‘pack leader’ through routine control of all resources and correction of any perceived challenge for them. At its most extreme this included physical punishment and steps to inhibit any initiative by the dog, including free movement and social interaction. The theory evolved from early to mid 20th century research into captive wolf behaviour, embellished by subsequent generations of dog trainers and behaviourists. However, more recent research into the behaviour of non-captive wolves and domesticated dogs, both in the home and living ferally, has brought the dominance theory into question. Perhaps more importantly, progress in the fields of animal welfare and training have highlig...
... There is a trend in some studies for male dogs to be reported as more aggressive than female dogs, (e.g. Borchelt 1983, Fatjó and others 2007, Pérez-Guisado and Muñoz-Serrano 2009 although univariable analysis was used in these studies). Guy and others (2001aGuy and others ( , 2001bGuy and others ( , 2001c found aggression in males to be context dependent. ...
Article
Risk factors for human-directed aggression were investigated using retrospective analysis of data from a referral-level clinical behaviour population in the UK. A sample of 200 cases involving human-directed canine aggression and 200 control cases involving no instance of human-directed aggression were selected at random from a population of 746 cases. The final model suggested that clinical cases with human-directed aggression were significantly younger than those presenting with other undesired behaviours (P=0.008) and that male dogs were 1.4 times more likely to be aggressive towards human beings than female dogs (P=0.019). Dogs were 1.7 times more likely to be aggressive towards people if they had attended more than five puppy classes than if they had never attended puppy class (P=0.015) and that dogs were 2.8 times more likely to be aggressive towards human beings if there was another dog between 0 months and 24 months of age in the home (P=0.004). These factors only account for 7 per cent to 10 per cent of the variance between the human-directed aggression population and the control population, but factors such as attendance at puppy classes and numbers of dogs in the household suggest the need for longitudinal studies to investigate temporal relationships.
... The literature also supports the view that multiple factors influence aggressive behavior, regardless of a dog's reproductive status. For example, Perez-Guisado and Munoz-Serrano found owner-dependent factors to be more significant than dog-dependent factors in influencing the aggressive behavior of dogs (37). Their studies showed more aggressive behavior from dogs owned by first-time dog owners, dogs with less obedience training, and dogs acquired as a gift or to guard. ...
Article
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Gonadectomy is widely used to treat and prevent behavior problems including the aggressive behavior of dogs. The aim of this study was to determine whether aggressive behavior toward familiar people, strangers, or other dogs was significantly different in dogs gonadectomized at various ages vs. intact dogs using the Canine Behavioral Assessment Research Questionnaire (C-BARQ) with multivariate analysis. Of 15,370 initial surveys, those for dogs reported to have been gonadectomized at less than 6 weeks of age or to correct a behavior problem, and those with incomplete answers to questions regarding independent or dependent variables were excluded, leaving 13,795 for the analysis of aggressive behavior toward familiar people: 13,498 for aggressive behavior toward strangers and 13,237 for aggressive behavior toward dogs. Aggressive behavior was defined (a) using mean scores for all questions on the C-BARQ for aggressive behavior (range 0–4) and (b) comparing dogs with no aggressive behavior (all questions answered 0) to dogs with moderate or severe aggression (at least one score of 2, 3, or 4). Data for intact dogs were compared with those for dogs gonadectomized at 6 months or less, 7–12 months, 11–18 months, and >18 months. Neither gonadectomy nor age at gonadectomy showed an association with aggression toward familiar people or dogs. However, there was a low but significant increase in the odds of moderate or severe aggression toward strangers for all gonadectomized dogs compared with intact dogs, but this effect was driven entirely by data for dogs gonadectomized at 7–12 months of age, which were 26% more likely to demonstrate aggression toward strangers. This large, comprehensive study of the relationships between gonadectomy and aggressive behavior in dogs demonstrates that when the many factors affecting aggressive behavior are considered, there is no evidence that gonadectomy at any age alters aggressive behavior toward familiar people or dogs, and there is only a minimal increase in aggression toward strangers. Given the increasing evidence of significant negative health effects of gonadectomy, there is an urgent need to systematically examine other means of preventing unwanted procreation, such as vasectomy and hysterectomy.
... Younger [21] or low socioeconomic status dog owners [22] have a greater risk of reporting canine behavioural problems. Previous ownership experience also plays a role, with firsttime dog owners reporting a higher prevalence of problem behaviours such as fear, over-excitability [23,24] and owner-directed aggression [23,25]. ...
Article
Full-text available
Dog ownership is popular worldwide, with most human-dog dyads forming successful attachment bonds. However, millions of dogs are surrendered to animal shelters annually, possibly due to mismatches between owner expectations and the realities of dog ownership. The aim of the current study was to explore the benefits and challenges people expect from dog ownership and how these expectations vary with previous ownership history. An Australian-wide sample of 3465 prospective adopters completed a self-administered online questionnaire about the physical, mental and psychosocial health benefits and challenges they associated with dog ownership. Among the potential benefits, respondents expected increased walking (89%), happiness (89%) and companionship (61%) and decreased stress (74%) and loneliness (61%). Among the challenges, they expected increased responsibility (64%) and dog training (62%). Ownership history influenced respondents’ expectations, with previous/current dog owners having consistently greater odds of expecting benefits and reduced odds of expecting challenges than non-owners. A possible explanation is that previous/current dog owners’ exhibit bias when considering dog ownership by selectively recalling positive experiences from previous ownership. Our findings support the need for education of prospective dog owners to ensure their expectations align with the reality of ownership, based on current scientific evidence.
... In intraspecific aggression, females appeared to be aggressive predominantly toward other females. Aggression incidences have been reported to be higher in males than in females in many other studies [60][61][62][63][64][65][66]. ...
Article
In this paper, we review the scientific reports of sex-related differences in dogs as compared to the outcomes described for wild animals. Our aim was to explore whether the differences in male and female dogs were affected by the domestication process, in which artificial selection is the main driver. For this purpose, we used information regarding personality traits, cognitive processes, and perception, for which there is a wide theoretical framework in behavioral ecology. Aggressiveness and boldness, described as a behavioral syndrome, were reported as being higher in males than females. Females also seemed more inclined to interspecific social interactions with humans in tasks that require cooperative skills, whereas males appeared more inclined to social play, thus implying different levels of social engagement between the sexes, depending on the context. Studies on cognitive processes underlined a greater flexibility in resorting to a particular navigation strategy in males. Most lateralization studies seem to support the view that males are preferentially left-handed and females are preferentially right-handed. Reports on visual focusing coherently rank females as superior in focusing on single social and physical stimuli. Only male dogs are able to discriminate kin; however, the timing of the olfactory recording in sexes is related to the stimulus relevance. Dogs are largely in line with life-history theories, which indicate that sex differences in dogs are mainly rooted in their biological and evolutionary heritage, remaining unchanged despite artificial selection. In contrast, the higher intraspecific sociability in wild male animals was not replicated in dogs.
... Some studies found a decrease of aggression in castrated dogs (Borchelt, 1983;Gershman et al., 1994;Messam et al., 2008;Kuhne, 2012), whereas others found opposite effects Serpell, 1997a, 1997b;Guy et al., 2001;Kaufmann et al., 2017) or no significant differences at all (van den Berg et al., 2006;Bennett and Rohlf, 2007). Furthermore, one study reported that dominance aggression decreased after castration in male dogs, whereas it increased in females (Pérez-Guisado and Muñoz-Serrano, 2009). Owner-directed aggression was found to decrease after castration (Hsu and Sun, 2010). ...
Article
Hormones influence the social behaviour of dogs. Castration of male dogs induces a reduction of testosterone and has been shown to affect social behaviours associated with aggression and reproduction. Changes in social behaviour could be critical in working dogs, which should be well trainable and behave reliably. It is currently unknown whether and how castration may affect the working ability of dogs. Besides surgical castration, chemical castration using a hormonal implant offers a possibility to castrate dogs temporarily. In the present study, we chemically castrated male Swiss military dogs and assessed their working abilities in comparison to intact males in a standard behavioural test series for Swiss military dogs (obedience, protection of the handler against an attacker, search of a hidden person in a building, reaction to social environment during a city walk). Chemical castration in Swiss military dogs had no measurable effect on any of the test situations in comparison to intact males.
... The most frequent canine behaviors considered to be problematic are usually characterized as anxiety (Flannigan & Dodman, 2001), aggressiveness towards people such as biting, growling (Perez-Guisado & Munoz-Serrano, 2009), and excessive vocalizations (Wells & Hepper, 2000;Ramazan, Day, & Phillips, 2016). The expression of such problematic behaviors can be associated with specific interactions between the dog and keeper, as an excessive attachment of a dog with his/her keeper can change their behaviors in an undesirable way (Guy et al., 2001;Jagoe & Serpell, 1996;Storengen, Boge, Strom, Loberg, & Lingaas, 2014). ...
Article
We characterized the reward patterns of dogs’ owners for the expression of desired behaviors of their pets through a questionnaire made available online on a social media page for 7 days (responses from over 66,676 owners). The questions were related to the type and frequency of rewards that pet owners applied and what specific dogs’ behaviors were rewarded. Desired behaviors of dogs were frequently reported to be rewarded. Responding correctly to commands and playing with their own toys were behaviors reported to be rewarded more frequently by owners than eliminating in appropriate places, a behavior perceived commonly just later. Moreover, owners reported that they rewarded more frequently by petting and praising the dogs and less frequently by applying a combination of giving both food and toys to their dogs. Thus, dog owners commonly reward desired behaviors by petting and prasing the dogs, most likely because it is the most convenient reward to use. Moreover, rewarding is more common when dogs express desired behaviors more immediately perceived by owners, which has welfare implications for these companion animals.
... We found a significant decline in canine behavioral problems among current dog owners, which might be explained by their ability to adequately adjust problematic behavior or by corrections from the other dogs present in the household [39]. Earlier cross-sectional research showed that first time dog owners report a higher prevalence of problematic behaviors, such as fear, over-excitability, and owner-directed aggression [40][41][42]. We found no differences in the number of reported behavioral problems between experienced and unexperienced owners, and a post-hoc analysis of separate behavioral problems did not support the aforementioned findings. ...
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In the framework of the early prevention of problems in the owner–dog relationship, it is important to have a broad perspective on the development of this relationship over time, starting before people actually acquire a dog. People who currently (or previously) own(ed) a dog can rely on their experiences when considering a new dog, while this knowledge is unavailable to first time dog-owners. In this study, we explore how self-efficacy, social comparison, perceptions about the (dis)advantages of ownership and commitment to the dog (so-called social cognitive factors), problematic canine behaviors, perceived costs, and satisfaction with the dog change over time. We examine changes from the motivational phase of relationship development (before acquisition of the dog) into the experience phase (six and twelve months after acquisition of the dog). We explore if patterns are different in experienced (previous (n = 73) and current (n = 80)) versus unexperienced (first time (n = 30) dog owners. The respondents filled in three online questionnaires—once before and twice after acquisition of their dog. From T0 (before acquisition of the dog) to T1 (having the dog for six months) participants (especially those with no ownership experience) had to adjust their perceptions about dogs and dog ownership. Experiencing the relationship for an additional year (from T1 to T2) barely changed the social cognitive factors, satisfaction, and perceived costs. A small decline in problematic canine behaviors was present among the experienced dog owners between T1 and T2. To conclude, perceptions about dogs and dog ownership change over time, but after testing these perceptions with reality, they become stable after about six months.
... The most commonly reported undesirable behaviors among clinical samples of dogs include aggression, destructiveness, fearfulness, excessive barking, and inappropriate elimination (Vacalopoulos and Anderson, 1993;Wells and Hepper, 2000;Landsberg et al., 2003;Kim et al., 2009). These behavioral issues in dogs may depend on a number of their characteristics (e.g., age, sex, breed, size, and neuter status), as well as some environmental factors including owners' characteristics (e.g., age, sex, level of experience and education, extent of interaction with dogs, diet, personality, and area of residence), and time and dog source of adoption (Podberscek and Serpell, 1997;Landsberg et al., 2003;Overall, 2005;Yalcin and Batmaz, 2007;Messam et al., 2008;Perez-Guisado and Munoz-Serrano, 2009;Khoshnegah et al., 2011;Martinez et al., 2011;Col et al., 2016;Cannas et al., 2018). Owing to the importance of problematic behaviors in dogs, numerous articles and research findings have been published worldwide including Iran; however, no similar research has been already conducted on the prevalence and relationships of such behavioral issues in the southwest of Iran (Beaver, 1994;Bradshaw et al., 2002;Hsu and Serpell, 2003;Bowen, 2008;Khoshnegah et al., 2011;Mashhadi Rafiei et al., 2011;Menor-Campos et al., 2011;Tamimi et al., 2013). ...
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Canine problematic behaviors are one of the most prevalent reasons given for referrals to small animal hospitals worldwide. Thus, the aim of the present study was to investigate the prevalence and possible variables related to 13 common problematic behaviors in 401 companion dogs referred to the Veterinary Hospital of Shahid Chamran University of Ahvaz, Iran. The results showed that 345 dogs (86%) had at least one problematic behavior. The main problematic behaviors reported for 345 dogs were excessive activity (38.7%), fearfulness (27.9%), destructiveness (27.2%), aggression toward unfamiliar people (23.7%) and roaming (22.4%). Small sized dogs were found to have higher fearfulness (P<0.001) and mounting and humping (P=0.005) than large sized ones. Fearfulness (P=0.008), withdrawal (P<0.001), aggression toward: unfamiliar people (P=0.003), dogs (P<0.001), and familiar people (P=0.01), respectively, and mounting and humping (P<0.001) were higher in the adult dogs than the puppies. Moreover, the female dogs were found to have higher fearfulness (P<0.001) and withdrawal (P=0.005) than the males. House soiling was significantly higher in dogs born in summer (P=0.005) and winter (P=0.008) than spring. Higher destructiveness (P=0.02) and house soiling (P<0.001) were found in dogs with a duration of ownership less than 6 months than those with more than 6 months. In the same vein, the outdoors dogs were found to have higher excessive activity (P<0.001) and aggression toward unfamiliar people (P=0.001) and dogs (P=0.005), whereas the higher fearfulness (P<0.001), withdrawal (P=0.02) and mounting and humping (P<0.001) were found in indoor dogs. Single dogs were found to have higher fearfulness (P=0.001) and mouthing and humping (P=0.004) than dogs from multi-dog homes. It is noteworthy that the higher mounting and humping was found more commonly in dogs owned by owners with academic degrees than those whose owners did not have any academic degrees (P=0.001). The findings proved the high prevalence of problematic behaviors in the studied companion dogs in the southwest of Iran. Veterinarians are expected to determine if there are any medical factors contributing to any behavior change in dogs, and decide whether their behavior change is typical, atypical, or pathological. However, dog owners should also be trained by veterinarians to know how to deal with problematic behaviors in dogs.
... Border collie dogs carrying GG genotype were more food possessive than dogs with AA genotypes. Food possessivity is often linked to possessive aggression, involving growling, baring the teeth, snapping, or biting when the dog possesses an object (food, bone, toy) and someone (family, stranger, animal) approaches and/or attempts to take it away [46,47]. However, food possessivity was unrelated to aggression in our test, as only a few dogs growled or attempted to bite. ...
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Background: Although the molecular function of wolframin remains unclear, the lack of this protein is known to cause stress in the endoplasmic reticulum. Some variants in the Wolfram Syndrome 1 gene (WFS1) were associated with various neuropsychiatric disorders in humans, such as aggressiveness, impulsivity and anxiety. Results: Here we present an in silico study predicting a single nucleotide polymorphism (rs852850348) in the canine WFS1 gene which was verified by direct sequencing and was genotyped by a PCR-based technique. We found that the rs852850348 polymorphism is located in a putative microRNA (cfa-miR-8834a and cfa-miR-1838) binding site. Therefore, the molecular effect of allelic variants was studied in a luciferase reporter system that allowed assessing gene expression. We demonstrated that the variant reduced the activity of the reporter protein expression in an allele-specific manner. Additionally, we performed a behavioral experiment and investigated the association with this locus to different performance in this test. Association was found between food possessivity and the studied WFS1 gene polymorphism in the Border collie breed. Conclusions: Based on our findings, the rs852850348 locus might contribute to the genetic risk of possessivity behavior of dogs in at least one breed and might influence the regulation of wolframin expression.
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Human–dog dyads represent a mutually beneficial partner- ship with a 16,000-year-old history. However, when this relationship becomes dysfunctional the consequences for the human, dog, and society at large can be severe. Canine members of dysfunctional dyads often display problem behaviors, such as aggression, and are frequently allowed to roam, becoming a public health concern. The cause of this dysfunction is multifactorial and includes human and canine personality factors as well as husbandry choices. By using our knowledge of these factors, there is a possibility of early identification of such pairings so that they can be corrected or even prevented. This study evaluated the factors that can contribute to the existence of dysfunctional human–dog dyads. Dog owners were asked to fill out questionnaires regarding their dog (general characteristics and the Canine Behavioral Assessment & Research Questionnaire) and themselves (general characteristics, education, family make-up, husbandry choices, and the Eysenck Personality Questionnaire-Revised). A total of 255 responses were obtained and differences between the two dyad types were found in hus- bandry choices and in both human and dog personalities. Using these factors, logistic regression was performed, and two models were obtained that could allow for the early identification of dysfunctional dyads. These models could be used to develop targeted educational programs, to better match dogs to new owners within the context of shelter medicine and help better tailor patient care in a clinical context.
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Records of dogs presented to a behavior clinic servicing the eastern seaboard of Australia in and around Brisbane and the Gold Coast were analysed for principal behavior problems and the related factors, from information recorded at the time that the owner approached the clinic for assistance. Data relating to 7,858 dogs presenting with 11,521 behavior problems between 2001 and 2013 were analysed. Twenty-two principal behavior problems were identified, of which the most common, in declining order, were aggression towards people, barking and anxious behavior. Male dogs were at greater risk of several behavior problems, compared to female dogs. Low socioeconomic status of owners and a short period spent at home each week were also associated with a greater risk of several behavior problems. The prevalence of breeds and breed groups presented to the clinic were compared with dog registrations at the local city council, and there were more working dogs, hounds and utility dogs and fewer terriers, toy dogs and non-sporting dogs in the clinic population. Uncommon breeds were over-represented in the clinic population compared to local registrations. The risk of developing behavior problems is discussed in the light of evidence about the dogs and their owners.
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In 1972, Campbell developed a test for selection of puppies, aiming to determine their degree of dominance to direct them to a compatible activity or family. In the present study, The Campbell test, as it became know, was applied to puppies from five breeds seeking possible behavioral differences. The puppies (138 Labrador retriever; 71 Rottweiler, 31 Bull Terrier, 13 English Cocker Spaniel and 12 Pit Bull), ranging from six to eight weeks of age, were tested in the kennels where they born. The results were analyzed statistically through the Kruskal-Wallis' test, and the comparison between pairs was done using the Mann-Whiteny's test. The Labrador Retrievers' puppies scored higher when compared to Rottweilers (p= 0,02) and Bull Terriers (p=0,02). These results suggest a higher attraction of the Labrador puppy or a greater independence of the Rottweiler and Bull Terrier puppies in relation to human beings, whereas the steps of the Test of Campbell that showed the most difference were those in which the puppy has to show interest by the examiner.
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For many people a good guard dog is a dog that defends aggressively the property that is to say a dog with high levels of territorial aggression. Nevertheless, this advantage can turn into a problem when the dog attacks friends and family, or when the dog disturbs our neighbours with excessive barking at strangers. The study involved carrying out 711 surveys on dog owners. The survey analyses many factors that might be linked to territorial aggression. The results show that there are many factors that are connected to higher levels of territorial aggression and which depend on the owner: not punishing the dog when it does something bad; a high level of education (university studies) and if the animal is acquired as a guard dog. It also found dog-dependent factors associated with territorial aggression: sex (male); certain breeds; FCI groups 5 and 7 and aged between 3 and 7 years. Furthermore, we discovered certain dog behavioural factors that are associated with a higher level of territorial aggression, such as: having as favourite games tug-of-war or bring things, a long time spent eating; if the dog barks a lot; if it attacks strangers randomly; if it tends to bite upper limbs and how nervous the dog is.
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Background Although the molecular function of wolframin remains unclear, the lack of this protein is known to cause stress in the endoplasmic reticulum. Some variants in the Wolfram Syndrome 1 gene (WFS1) were associated with various neuropsychiatric disorders in humans, such as aggressiveness, impulsivity and anxiety. Results Here we present an in silico study predicting a single nucleotide polymorphism (rs852850348) in the canine WFS1 gene which was verified by direct sequencing and was genotyped by a PCR-based technique. We found that the rs852850348 polymorphism is located in a putative microRNA (cfa-miR-8834a and cfa-miR-1838) binding site. Therefore, the molecular effect of allelic variants was studied in a luciferase reporter system that allowed assessing gene expression. We demonstrated that the variant reduced the activity of the reporter protein expression in an allele-specific manner. Additionally, we performed a behavioral experiment and investigated the association with this locus to different performance in this test. Association was found between food possessivity and the studied WFS1 gene polymorphism in the Border collie breed. Conclusions Based on our findings, the rs852850348 locus might contribute to the genetic risk of possessivity behavior of dogs in at least one breed and might influence the regulation of wolframin expression.
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Pediatric gonadectomy is most commonly performed by humane organizations as a means of population control. Benefits and detriments of gonadectomy are reviewed, with special attention to literature describing effects specific to age at gonadectomy. Techniques for pediatric anesthesia and surgery are reviewed.
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This article reviews studies of different dog bites directed toward people. Typical bite events are summarized by describing the characteristics of the dog, victim, and wound; serious bites (severe and fatal bites) are described separately. Suggestions for the prevention of dog bites are presented.
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To evaluate fluoxetine for the treatment of owner-directed dominance aggression in dogs. Prospective study. 9 dogs of various breeds, ages, and either sex determined to have owner-directed dominance aggression. Placebo and fluoxetine (1 mg/kg of body weight) were compared for the treatment of owner-directed dominance aggression in a single-blind crossover study. Owners were instructed to record aggressive and nonaggressive responses of their dogs daily on a canine-overt aggression chart for the 5-week duration of the study. Total aggression scores (linear and geometric) were calculated for each week of the study. The frequency of individual responses was also analyzed independently. Fluoxetine resulted in a significant (P = 0.01) reduction in owner-directed dominance aggression after 3 weeks of treatment. No particular aggressive response accounted for the overall reduction in aggression. Fluoxetine may be useful in the management of dominance aggression in dogs.
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This study was undertaken to characterize 20 cases of dominance aggression seen at Tufts University School of Veterinary Medicine and to investigate the efficacy of our non-confrontational behavior modification program for 8 weeks. The 20 cases included 18 pure breed and 2 mixed breed dogs. Thirteen of the dogs were male. The dogs' ages ranged from 7 to 84 months (mean 32.1 +/- 22.64 SE). There was no correlation between the severity of dominance aggression and the signalment of the dogs. At the conclusion of the eight week follow up period, 14 dogs (70%) were reported to have responded to the treatment to some degree. Six dogs did not demonstrate any noticeable reduction in aggressive behavior or became more aggressive. The results of the study is powerful evidence of the efficacy of the non-confrontational behavior modification program.
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The aim of the study was to determine whether there is an association between the personality of the owners of English cocker spaniels and the expression of aggressive behaviour by their dogs. Two-hundred-and-eighty-five owners of purebred English cocker spaniels completed the Catell 16 Personality Questionnaire. One-hundred-and-twenty-eight of them owned 153 dogs previously classified as being 'low' in terms of aggressiveness and 157 owned 172 dogs classified as being 'high' in terms of aggressiveness. Both groups of owners were similar in terms of a variety of demographic variables, including the number of adults and children in the household, the type of house and the sex of the owner. The dogs in both groups were similar in age, age when acquired and sex ratio. Analyses of the data using unpaired t-tests revealed that the owners of high aggression dogs were significantly more likely to be tense (P < 0.001), emotionally less stable (P < 0.01), shy (P < 0.01) and undisciplined (P < 0.05) than owners of low aggression dogs.
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The aim of this study was to evaluate the Campbell test and discover if there is a link between a puppy's scores and factors such as age, breed, sex, sex-breed interaction, size, Fédération Cynologique Internationale (FCI) groups, and coat color. The Campbell test was performed on 342 puppies (191 males and 151 females) of different breeds. The results show that the criteria used by Campbell to classify puppies are incomplete, and that it is more appropriate to use numerical values for each type of answer. In general, the mean value obtained, regardless of sex and breed, corresponded to the Campbell's submissive stable category. The mean value was higher in male dogs than in females.