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Aggressive behavior in the English Cocker Spaniel
Abstract
A high percentage of aggression problems and a tendency to display noninhibited aggression in the English cocker spaniel (ECS) have been suggested by many authors. The authors of this paper designed a retrospective study to analyze the aggressive behavior of 145 ECSs presented for aggression problems to the Animal Behavior Service at the Barcelona School of Veterinary Medicine's veterinary teaching hospital. Aggressive ECSs were compared with a population of dogs of the same breed presented for a behavior problem other than aggression and with a population of aggressive dogs of other breeds. The most common forms of aggression in the ECS were owner-directed aggression (67.6%), aggression toward unfamiliar people (18.4%), aggression toward unfamiliar dogs (10.1%), and aggression toward family dogs (3.3%).Owner-directed aggression was more common in the ECS than in other breeds, although in similar contexts. In the ECS, the golden coat color was more common in the aggressive dogs than in nonaggressive dogs. ECSs showed impulsive aggression more frequently than aggressive dogs of other breeds. The aim of the study was to analyze cases of aggressive ECSs seen in a referral practice.
... A review of breed predisposition of diseases across all dog breeds identified 63 disorders with some evidence of predisposition for the ECS [9], including otitis externa [10], immune-mediated haemolytic anaemia [11,12], pancreatitis [13], chronic hepatitis [14], and several ocular conditions such as glaucoma [15]. Further, ECS are over-represented in studies evaluating canine aggression [16,17], and the prevalence of aggression has been generally reported as higher in males than in females [16,[18][19][20]. It has also been reported that solidcoloured ECS are more likely to show signs of aggression than bi-coloured or tri-coloured, and that golden and red-coated ECS are more likely to show aggression than black-coated [20][21][22][23]. ...
... Further, ECS are over-represented in studies evaluating canine aggression [16,17], and the prevalence of aggression has been generally reported as higher in males than in females [16,[18][19][20]. It has also been reported that solidcoloured ECS are more likely to show signs of aggression than bi-coloured or tri-coloured, and that golden and red-coated ECS are more likely to show aggression than black-coated [20][21][22][23]. However, the majority of studies reporting aggression in ECS were published over 15 years ago [16,17,[19][20][21] and were based on study populations attending referral animal behavioural clinics [16,19,20], which limits the generalisability of the results to the current general ECS population. ...
... It has also been reported that solidcoloured ECS are more likely to show signs of aggression than bi-coloured or tri-coloured, and that golden and red-coated ECS are more likely to show aggression than black-coated [20][21][22][23]. However, the majority of studies reporting aggression in ECS were published over 15 years ago [16,17,[19][20][21] and were based on study populations attending referral animal behavioural clinics [16,19,20], which limits the generalisability of the results to the current general ECS population. ...
Plain English summary
The English Cocker Spaniel (ECS) is a popular family dog in the UK, but there is limited information regarding common disorders affecting the breed. The goal of this study was to describe demography (age, sex, neuter, and bodyweight), disease occurrence, lifespan, and reasons for death in ECS by using data from the VetCompass™ Programme. The VetCompass™ Programme collects information from anonymised clinical records of dogs attending first-opinion veterinary practices in the UK. This study hypothesised that aggression is more common in males than in females, and in solid-coloured than in bi-coloured ECS dogs.
English Cocker Spaniels comprised 10,313/336,865 (3.06%) of dogs under primary veterinary care during 2016. Breed popularity did not vary much from 2005 to 2016, comprising around 3% of all dogs born each year. The average age of dogs in 2016 was 4.57 years and the average adult bodyweight was 15.05 kg. The most common disorders were periodontal disease (infection of the tissues that hold the teeth in place, affecting 20.97% of the dogs), inflammation of the external ear canal (10.09%), obesity (9.88%), anal sac impaction (8.07%), diarrhoea (4.87%), and aggression (4.01%). Aggression was more common in males (4.95%) than in females (2.87%) and in solid-coloured (7.00%) than in bi-coloured (3.66%) dogs. The frequency of aggression also varied across the four most common solid colours (black, liver, golden, red), with golden-coloured dogs showing the most aggression (12.08%). The average lifespan was 11.44 years and the most common cause of death was tumours.
This study shows that first-opinion clinical records can help us to understand and enhance breed health. The results can guide veterinarians in giving breed-adapted information to owners of ECS and help breeders to optimise breeding decisions. Further, this information can be used by future ECS owners to make more informed decisions when acquiring a dog if avoidance of aggression is a key priority. Periodontal disease was the most common condition affecting the breed, which highlights the importance of regular veterinary dental checks and as well as tooth brushing in ECS.
... Aggression can be influenced by genetics and environmental factors. Evidence of genetic effects on aggressive behavior has suggested that there may be breed effects (Amat et al., 2009;Duffy et al., 2008;Hart and Hart, 1985;Liinamo et al., 2007;Pérez-Guisado et al., 2006;Scott and Fuller, 1965). However, many studies have shown a large individual variation in behavior within breeds (Hart and Hart, 1985;Scott and Fuller, 1965;Wilsson and Sundgren, 1998) which indicates that preventive programs should be based on individuals rather than breed, itself. ...
... The effect of sex hormones was also considered a factor related to aggressive behavior in dogs. Some studies have found that males are overrepresented in the population of aggressive dogs (Amat et al., 2009;Borchelt, 1983;Fatjó et al., 2007;Reisner et al., 2005). Testosterone seems to act as a behavior modulator that allows the dog to react more quickly and intensely and for a prolonged period of time (Overall, 2013), and this may explain why male dogs are overrepresented in some studies of aggression. ...
... Moreover, in the present study, there were also aggressive dogs in the control group. In general, testosterone can act as a behavior modulator that allows the dog to react more quickly and intensely and for a prolonged period of time (Overall, 2013) and this may explain, at least in part, why, in some studies (Amat et al., 2009;Borchelt, 1983;Fatjó et al., 2007;Reisner et al., 2005), males are overrepresented. ...
Canine aggression toward family members represents a potential hazard for the owner's health and can severely compromise the welfare of the affected dogs. The aim of this retrospective study was to investigate the main features of canine aggression toward family members using cases from a referral practice. The cases were examined with respect to behavioral and environmental factors that may be related to this problem. Forty-three cases of canine aggression toward family members seen at the Animal Behavior Clinic (Barcelona School of Veterinary Medicine) were analyzed and compared with 50 canine cases with no such history. A logistic regression model was applied to identify environmental and behavioral factors that may be related to aggression toward family members. Dogs adopted before 7 weeks of age and those receiving treats from the table were more likely to present aggression toward family members. Dogs presenting an underlying painful condition were also more likely to be aggressive toward family members. According to the owner's description, most of the dogs showed an ambivalent posture during the aggressive events. These findings provide an insight into some of the factors related to canine aggression toward family members and may help to develop more effective preventive and treatment strategies. Even if causative links cannot be made, our findings certainly provide direction for further investigation.
... In mountain sheep, higher rank has been shown to be associated with increasing darkness of coat, and darker rams were seen more often tending oestrous ewes (Loehr et al., 2008). In the case of dogs, a relationship exists between coat colour and aggressive behaviour in the case of English cocker spaniels, where animals with a solid coat colour show higher levels of aggression than those that are parti-coloured Serpell, 1996, 1997;Pérez-Guisado et al., 2006;Amat et al., 2009). ...
... Quantitative, experimental investigations of the relationships between coat colour and behaviour have been carried out since the 1940s with studies on laboratory rats, ranch mink and foxes. Several mechanisms have been suggested to explain observed connections between coat colour and temperament traits (Keeler, 1942;Hemmer, 1990;Amat et al., 2009). One such possible mechanism is that that melanin which is key to pigmentation has a similar biochemical synthesis pathway to dopamine and other neurotransmitters, which contribute to the control of behaviour. ...
... In this study, no significant differences based on the coat colour could be observed in terms of aggressive reactivity. This is not consistent with the previous studies which used different behavioural evaluation methods from the present study and found differences in the level of aggression within the same breed of English cocker spaniels depending on different coat colours Serpell, 1996, 1997;Pérez-Guisado et al., 2006;Amat et al., 2009). There are many potential causes of aggressive behaviours in dogs, among which those that trigger aggressive behaviour for territorial defence seem to be the most prominent. ...
This study aimed to compare the behavioural reactivity of Jindo dogs with two different coat colours. Fawn (16 males, 15 females; mean age+/-S.D.=7.2+/-2.1 years) and white (10 males, 10 females; mean age+/-S.D.=6.9+/-2.1 years) Jindo dogs were exposed to a set of behavioural tests. All of the dogs were videotaped during the testing period to allow further analysis. The intensity of social, aggressive, fearful, and submissive reactivity and the frequency of urination as a scent-marking behaviour were scored on a scale running from 0 to 4 points. For each dog, each variable was defined as the average of the scores of nine behaviour tests. Then, the behavioural reactivities of Jindo dogs of each coat colour were compared. The results suggested that Jindo dogs of fawn coat colour exhibited a significantly lower intensity of fearful and submissive reactivity than those of white coat colour. In addition, fawn Jindo dogs produced scent-marking behaviour significantly more frequently. The results of the present study may provide useful information for scientific researchers, potential owners and breeders of Jindo dogs.
... However, the same construct has been tentatively applied to dogs, where high impulsivity is thought to be a correlate of different maladaptive behavioural manifestations or cognitive processes. For instance, impulsivity may play a role in aggression [17,18], and more generally in the expression of behavioural problems [19]. Furthermore, some evidence suggests that impulsivity is associated with lower problem-solving abilities [20,21]. ...
... A much smaller variety of tasks assess impulsive choices. Although with some variations in the nature or the source (social or non-social) of the reward, these methods are based on the same general paradigms which measure dogs' ability to tolerate temporal delays on the expectation of a larger/more valuable reward [17,25,[27][28][29]. A common disadvantage of these delay-discounting tasks is that they generally require dogs to undergo a long training (in most cases lasting more than one day), which also makes it difficult to complete the test as proved by a relatively low success rate (e.g., 58.8% [19]; 51.4% [30]). ...
Simple Summary
Impulsivity is believed to play a role in problematic behaviors in dogs. In this study, we developed a test to assess dogs’ tendency to make impulsive choices, that is their preference for smaller immediate reward instead of larger, but harder to obtain ones. Dogs were first trained that a bowl presented on a certain side always contained a large food amount, whereas the one presented on the opposite side (although at the same distance from the dog) contained less food. Then, the bowl with less food was progressively placed closer to the dog. As expected, dogs’ choices to feed from the bowl with less food increased as the distance of the latter decreased. Choices did not depend on factors that could interfere, such as dogs’ level of motivation for food, training experience, or learning ability. This indicates that the test is likely to be actually assessing impulsivity, not other traits. Also, female dogs were more likely to make impulsive choices than males, in accordance with what is known in humans and rodents, supporting the validity of the test. The test was completed in less than 1 h, making it a valid option to assess impulsivity in dogs in various contexts.
Abstract
Impulsive choices reflect an individual’s tendency to prefer a smaller immediate reward over a larger delayed one. Here, we have developed a behavioural test which can be easily applied to assess impulsive choices in dogs. Dogs were trained to associate one of two equidistant locations with a larger food amount when a smaller amount was presented in the other location, then the smaller amount was placed systematically closer to the dog. Choices of the smaller amount, as a function of distance, were considered a measure of the dog’s tendency to make impulsive choices. All dogs (N = 48) passed the learning phase and completed the entire assessment in under 1 h. Choice of the smaller food amount increased as this was placed closer to the dog. Choices were independent from food motivation, past training, and speed of learning the training phase; supporting the specificity of the procedure. Females showed a higher probability of making impulsive choices, in agreement with analogue sex differences found in human and rodent studies, and supporting the external validity of our assessment. Overall, the findings support the practical applicability and represent a first indication of the validity of this method, making it suitable for investigations into impulsivity in dogs.
... Also, male dogs with stranger-directed aggression were more likely to bite or attempt to bite when compared to female dogs. Male dogs have previously been reported to show higher rates of aggression than females (Amat et al., 2009;Borchelt, 1983;Casey et al., 2014;Fatjo et al., 2007;Gershman et al., 1994;Lund et al., 1996). One study looked at the interaction between neutering and sex, and found that neutering was associated with stranger-directed aggression in females, but the relationship disappeared when dogs that were neutered due to aggression issues were removed from the model (Podberscek and Serpell, 1996). ...
... However, another study found that stranger-directed aggression was lowest in neutered females when compared to all other categories (Casey et al., 2014). Studies examining the effect of neutering independent of sex have found mixed results (Amat et al., 2009;Gershman et al., 1994;Goodloe and Borchelt, 1998;Matos et al., 2015;Podberscek and Serpell, 1997;van den Berg et al., 2006). The differences could be due to sex-based differences in relation to neutering effect, sample size and statistical variability, or differences in classification of aggressive behaviour. ...
Aggression in dogs is a safety concern both for humans and animals, and can lead to decreased animal welfare in affected dogs due to potential abuse, neglect, relinquishment or euthanasia. We examined risk factors associated with stranger-directed aggression in dogs using the previously validated, Canine Behavioural Assessment and Research Questionnaire (C-BARQ). Results are based on participant reports of dog behaviour. Data were analyzed using mixed logistic regression, with participant ID and country as random effects. Dogs (n = 14,310) were more likely to demonstrate stranger-directed aggression if the participant rated them as mildly or severely fearful of strangers, or mildly, but not severely, fearful in non-social situations, when compared to dogs with no fear. There was an interaction between sex and neuter status, with neutered males being more likely to be aggressive than any other group. Furthermore, adult dogs were more likely to be aggressive compared to adolescents or seniors, and dogs were less likely to be aggressive if acquired as an adult when compared to being acquired as a puppy or adolescent. The random effects for country and participant were significant (p. <. 0.001) with ICCs of 0.01 (CI: 0.00-0.08) and 0.40 (CI: 0.35-0.46), respectively, indicating that there was some correlation in behaviour among dogs within the same country and owned by the same person. The moderate effect of participant suggests that household effects need to be examined further. When looking only at dogs categorized as aggressive towards strangers (n = 11,240), dogs were significantly more likely to be categorized as having severe aggression if they were male, and if the owner rated them as mildly or severely fearful of strangers, or mildly, but not severely, fearful in non-social situations, when compared to dogs with no fear. Breed group and where the dog was acquired also had an association with severe aggression. The random effects for country and participant were significant (p. <. 0.001) with ICCs of 0.06 (CI: 0.02-0.15) and 0.34 (CI: 0.22-0.48), respectively, indicating once again that there was some correlation in behaviour among dogs within the same country and owned by the same person. These results suggest that variables related to the environment, owner experience and the dog's level of fearfulness are associated with aggressive behaviour towards strangers in dogs. Therefore, it might be possible to identify dogs at risk of developing stranger-directed aggression and implement plans to prevent behavioural issues from developing.
... For example, competitive displacement of adrenocorticotropic hormone (ACTH) from the melanocortin 2 receptor would inhibit glucocorticoid synthesis (Almasi et al., 2010), and lower glucocorticoid levels have been linked to diminished aggression in dogs (Rosado et al., 2010) and other vertebrates (Kruk et al., 2004;Summers and Winberg, 2006). In support of this mechanism, there is evidence that black dogs have lower basal cortisol levels (Bennett and Hayssen, 2010) and aggression rates (Houpt and Willis, 2001;Amat et al., 2009) than nonblack dogs. Previous studies on this population indicate glucocorticoid levels changed with dominance status but not with intra-pack aggression (Creel, 2005). ...
... It is possible that the K-locus, like other melanin-based coloration genes, is associated with physiological and behavioral traits (e.g. immune function, stress response) through pleiotropic effects on the melanocortin system (Ducrest et al., 2008) as has been shown in black dogs having lower basal cortisol levels (Bennett and Hayssen, 2010) and aggression rates (Houpt and Willis, 2001;Amat et al., 2009) than nonblack dogs. Our results indicate the K-locus may influence hormones and consequently influence behavior, as black wolves were less aggressive than gray wolves during aggressive encounters. ...
... However, in a study by Hart and Miller (1985), breeds ranked by judges as showing the greatest tendency to "exert dominance over their owners" or snap at children were not consistent with these more recent owner surveys. Studies of veterinary caseloads consistently report the English Cocker Spaniel (Amat et al., 2009;Beaver, 1983;Borchelt, 1983;Fatjó et al., 2007;Wright and Nesselrote, 1987) and the English Springer Spaniel (Guy et al., 2001;Landsberg, 1991;Reisner et al., 1994) as exhibiting the highest levels of ODA. ...
... The reverse effect was found for English Springer Spaniels, such that conformation-bred individuals tended to be more owner-aggressive than fieldbred individuals (Duffy et al., 2008). Aggressive individuals within a breed have also been linked to yellow coat color in Labradors (in Houpt and Willis, 2001;Kobelt et al., 2007) and golden coat color in English Cocker Spaniels (Amat et al., 2009;Podberscek and Serpell, 1996). This may be due to an overlap in the biochemical synthesis pathways of melanin and dopamine and other neurotransmitters (e.g., low levels of serotonin) that contribute to the expression of aggressive behavior (Hemmer, 1990). ...
... Further studies evaluating the possible differences in physical exercise and diet between breeds could be useful. ECSs are obtained more frequently from pet shops that dogs of other breeds (Amat et al., 2009), perhaps owing to the popularity of this breed (Serpell and Jagoe, 1995). Dogs obtained from pet shops have more behavioral problems than those obtained from other sources, probably owing to the early weaning and a stressful environment in the pet shop (Serpell and Jagoe, 1995). ...
... Studies in laboratory rats indicate that decreasing serotonergic activity intensifies impulsiveness, whereas increasing serotonergic activity enhances the preferences for delayed rewards (Manuck et al., 2003). A previous study found that ECSs show impulsiveness more frequently than other purebred dogs (Amat et al., 2009 ), and impulsive aggression is one of the main risk factors for euthanasia of aggressive dogs (Reisner et al., 1994). Violent impulsive humans have lower levels of 5-HIAA in cerebrospinal fluid than violent individuals who had committed a crime with premeditation (Virkkunen et al., 1995 ). ...
Aggression is one of the most common behavioral problems in dogs and may have important negative effects on public health, human–animal bond, and animal welfare. There is ample evidence showing a negative correlation between serum serotonin concentration and aggressive behavior in a variety of species, including the domestic dogs. This negative correlation is particularly pronounced in dogs that show impulsive aggression. Data obtained in some previous studies suggest that the English cocker spaniel (ECS) is more likely to show impulsive aggression than other breeds. Therefore, the aim of this study was to analyze possible differences in serum serotonin levels between aggressive ECS and aggressive dogs of other breeds. Nineteen ECSs presented for aggression at the Animal Behavior Service (School of Veterinary Science, Barcelona, Spain) were evaluated and compared with 20 aggressive dogs of other breeds attended at the same center. Serum serotonin levels were measured using an enzyme-linked immunosorbent assay method. Statistical analysis was done using the SPSS 15.0 for Windows. Aggressive ECSs had significantly (P < 0.001) lower levels of serum serotonin than aggressive dogs of other breeds (318.6 ± 67.1 and 852.77 ± 100.58 ng/mL, respectively). Variances were not significantly different between ECSs and other breeds (standard deviation = 449.84 ng/mL vs. 292.47 ng/mL, P > 0.05). This finding may explain why ECSs are more likely to show impulsive aggression than other breeds, and suggests that the ECS could be a good model to study the neurophysiologic mechanisms underlying impulsive aggression.
... Although most dogs are well behaved within the English Cocker Spaniel (ECS) breed, single dogs with significant behavioural problems have been periodically described for several decades (Amat et al. 2009;Mugford 1984;Podberscek & Serpell 1996). Breeders and owners observed that aggression tended to be associated with specific breeding lines, indicating a strong genetic component. ...
... In an earlier recognition of aggression in the ECS (Amat et al. 2009;Mugford 1984;Pérez-Guisado et al. 2006;Podberscek & Serpell 1996), a higher frequency of aggression has been reported in solid coloured (especially in solid dogs with the red colour) compared with parti-coloured dogs. Within our study population, only 10% of the aggressive dogs are particoloured compared to 65% of the controls. ...
Human-directed canine aggression was studied using 50 aggressive and 81 non-aggressive dogs. We examined 62 single nucleotide polymorphisms (SNPs) occurring in or in the close vicinity of 16 neurotransmitter-related genes. Allelic associations with aggression were identified for DRD1, HTR1D, HTR2C and SLC6A1. Risk or protective haplotypes for aggressive behaviour based on 2-5 SNPs were identified. The frequency of aggressive dogs varied significantly between the haplotypes within loci and the odds ratios of aggression in dogs with risk haplotypes compared with protective haplotypes varied from 4.4 (HTR2C) to 9.0 (SLC6A1). A risk haplotype across the neurotransmitter receptor gene HTR1D harboured a non-synonymous SNP with a potential effect on protein function. We identified no haplotypes in complete association with the recorded phenotypes, supporting a complex inheritance of aggression.
... Estas diferencias, pueden ser debidas a las diferencias regionales y culturales. El hecho de que la raza Cocker tienda a ocupar el primer lugar en agresividad hacia personas dentro de las consultas de etología clínica, y que ocupe el segundo lugar en el factor de riesgo, luego del Rottweiler, coincide con reportes internacionales (Amat, Manteca, Mariotti, Ruiz de la Torre & Fatjó, 2009;Beaver, 1983;Blackshaw, 1991;Fatjó et al., 2007;Pageat, 1998;Podberscek & Serpell, 1996;Scott & Fuller, 1965;Wright & Nesselrote, 1987). Por otro lado, la raza Cocker no aparece en forma frecuente en los registros del SAM-MSP. ...
Statistics about clinical data is lacking in Uruguay. Herein, we present an account of canine behavioral problems recorded from different sources: a) clinical reports on canine behaviour, from 30 veterinary clinics in Montevideo city from 2005 to 2007 (n = 179); b) records of dog attacks to people (n = 992) reported at the Servicio de Atención al Mordido (Ministerio de Salud Pública, same period); and c) conflicts from records of Comisión Nacional Honoraria de Zoonosis (n = 44,000). Based on these data we discus common behavioral problems, types of aggression involved, the frequency of male / female, if they were neutered or not and the age at the onset of the first episodes of aggression. For each record we obtained an aggressive risk factor associated to breed. The results are consistent with international reports, where the aggression was the most common behavioral problem (58.9%), and dominance aggression has the highest proportion (56%). The RDPCC records revealed that the proportion of animals involved in aggression is similar in both genders. However, SAM-MSP records showed that males (71%) were a significantly greater proportion than females (29%). Our data from RDPCC showed that 100% of males involved in aggression towards people were whole, while 38.5% females were castrated. The first signs of canine aggression towards people were observed in first year of life in 56.5% of cases. On the other hand, while the RDPCC record suggests that Cocker breed tended to show more attacks of aggression toward people, the SAMMSP record pointed to the German Shepher as the more aggressive breed. The Rottweiler and Uruguayan Cimarron, occupied the first and third place respectively in the aggressive risk factor rank associated to breed, both in RDPCC and SAM-MSP set of records. This is the first descriptive work on dog behavior problems and aggression in Montevideo, where also is shows the implication of the Cimarron uruguayo race in aggression.
... Furthermore, the short form of the tyrosine-hydroxylase gene seems to be involved in dopamine synthesis in German Shepherd and Siberian Huskies with altered social behaviors [47]. Because of this, behavioral genetics studies on aggressive dogs aim to quantify blood and cerebrospinal fluid dopamine levels, as well as its expression in the brain. ...
According to Acheson Roy, the constant aim in epidemiology is that of answering the question ‘why did this individual develop this disease in this moment of time?.’ Similar to studies applied in classical epidemiology, observational epidemiological studies in genetics are divided into descriptive and analytical. Descriptive studies verify the variance model of the disease or behavior and can offer clues about the involvement of genetic or environmental factors. Analytical studies establish the causal effect (genetic cause) on the disease or behavior phenotype; in the case of an existing genetic cause, it remains to be identified. An analytic study model would be appropriate for the analysis of idiopathic aggressivity and epilepsy in dogs. In some cases, common etiological factors can be the basis of both situations. One such potential factor can be changes in dopaminergic function codified by the SLC6A3 gene. In the central nervous system of mammals, dopamine is a key neurotransmitter involved in locomotory activity, objectives, and reward processing-oriented behavior, as well as in convulsive activity.
... In previous studies, male dogs have shown high rates of stranger-directed aggression but this was not repeated in this study [45][46][47][48][49][50][51]. Use of behavior medications in the shelter was associated with higher stranger-directed aggression scores post adoption. ...
Despite millions of dogs entering and exiting shelters annually, little is known about dog behavior long-term after adoption. Entering a shelter is stressful for dogs which may inhibit or exaggerate behavior. There is a common public sentiment that dogs have a “honeymoon period” after adoption where dogs do not show their full repertoire of behaviors, both positive and negative, until getting more comfortable in their new home. The aim of this prospective observational cohort study was to identify prevalence of and changes in behavior issues in dogs throughout the first six months following adoption. The owners of ninety-nine dogs adopted from five Ohio shelters between October 1, 2020 and June 1, 2021 were surveyed 7, 30, 90, and 180 days after adoption, using the Canine Behavioral Assessment & Research Questionnaire (C-BARQ). Owners were also asked about household changes that may affect behavior. Estimated age, sex, weight, length of shelter stay, shelter intake reason, use of gastrointestinal, antibiotic, and psychotropic medications in the shelter, whether the animal had been previously returned to the shelter, and whether the owner was a first-time dog owner, were evaluated as predictors in a mixed effect regression model of different behavior measures over time. At various timepoints, dogs showed high prevalence for stranger-directed aggression (81.7%), owner-directed aggression (32.3%), dog-directed aggression (75%), familiar dog aggression (37.8%), stranger directed fear (58.2%), nonsocial fear (95.8%), dog directed fear (80.0%) and separation-related behaviors (92.6%). Over 180 days, stranger-directed aggression, excitability, touch sensitivity, training difficulty, and chasing increased, while separation-related behaviors, attachment and attention-seeking decreased. Owners reported high satisfaction with their dogs’ behavior. Use of psychotropic medications in the shelter was predictive of stranger-directed aggression and touch sensitivity at home. These findings help veterinarians and shelter professionals council owners on potential behavior changes after adoption.
... Companionship is the primary reason for the adoption of dogs today by humans [2,3]. Dog behavior problems, which include unacceptable behaviors to the owners, are a serious concern to public health and economic and animal welfare [4]. Aggressive behavior and biting incidences among Thai dogs are often reported in the media, and these behaviors can be found among both pet and stray dogs. ...
Background and Aim: Dog behavior problems pose serious public health and economic and animal welfare concerns. There are many factors influencing dog behavior. This study aims to explore factors associated with pet dog behavior in Thailand using the Canine Behavioral Assessment and Research Questionnaire (C-BARQ).
Materials and Methods: The Thai version of the C-BARQ was validated in 2022. The online C-BARQ survey (Google Forms) was advertised and distributed on social media for 3 months. There were a total of 1827 respondents to the survey. The relationship among 12 subscales and variables was analyzed using Spearman’s correlation.
Results: “Excitability,” “attachment- and attention-seeking,” and “chasing” were the three most reported behavior problems. “Trainability,” a favored dog behavior, also had a high score in the study. These behaviors were associated with the owner’s age, house type, the dog’s historical background, the number of dogs and the presence of other species in the household, the dog’s training, diet types, and the daily number of meals. The lowest mean score was for “owner-directed aggression,” and it was associated with the dog’s gender and size, the number of dogs and the presence of other species in the household, the dog’s training, and the number of daily meals.
Conclusion: This is the first empirical study demonstrating factors related to dog behavior in Thailand. It provides an in-depth understanding of the prevalence and factors associated with Thai pet dog behavior and important knowledge for further studies to advocate for dog–human relationships and contribute to a reduction in dog abandonment in Thailand.
... Within the literature on psychiatric disorders involving aggressive behaviour in humans, high impulsivity and poor executive control have been highlighted (Dalley & Robbins, 2017). Previous work on dogs has considered impulsivity in relation to a heightened risk from aggressive behaviour due to reduced preceding threat signals (Amat et al., 2009;Peremans et al., 2003), and this may be very pertinent to the perceived dangerousness of a dog (i.e. ability to predict aggression from lower level threats and take appropriate steps to prevent a bite). ...
Aggressive behaviour by dogs is a considerable social problem, but the ability to predict which individuals may have increased aggressive tendencies is very limited, restricting the development of efficient preventive measures. There is a common perception that certain breeds are more likely to exhibit aggressive behaviour, which has contributed to the introduction of breed‐specific legislation. The rationale for such legislation explicitly assumes high heritability of this trait while also implying relatively little variation within breeds; these assumptions are largely untested. We compared behavioural tendencies between 8 breeds that are subject to legislation in at least one country and 17 breeds that are not subject to legislation using two validated psychometric tools: the Dog Impulsivity Assessment Scale (DIAS), which scores elements of impulsivity, including a tendency for aggressive behaviour, and Positive and Negative Activation Scale (PANAS), which scores sensitivity to positive and negative stimuli (which may trigger aggressive responses). We found that the two groups of breeds do not differ significantly in the specific DIAS factor relating to aggressive behaviour, “Aggression Threshold and Response to Novelty”, or any other DIAS and PANAS factors. We found large variations in all behavioural tendencies measured by both psychometric scales within both groups and within each breed studied. Taken together, our findings indicate that breed alone is not a reliable predictor of individual behavioural tendencies, including those related to aggression, and therefore breed‐specific legislation is unlikely to be an effective instrument for reducing risk.
... Another mechanism mediated by executive control is impulsivity (42), which is often described in the context of canine aggression (5,43,44). While the association between selfcontrol, measured as performance in delay of gratification test, and aggression has not yet been assessed in dogs, it has been proposed that delay of gratification test is an index of impulsive behavior and that lack of self-control in dogs may also be referred to as impulsivity (5). ...
Inhibitory control describes a multitude of cognitive processes that prevents an impulsive response and enables a more appropriate behavior in a given situation. The ability to inhibit undesirable behaviors, such as aggression, is particularly important in dogs for safe and successful interspecific interaction and cooperation. The present study investigated the associations between two aspects of inhibitory control in dogs, self-control and cognitive inhibition, and the tendency to respond aggressively when provoked. Sixteen police and fourteen privately owned dogs of the same sex, breed group and similar age participated. Self-control, often described as impulsivity, was measured with an exchange paradigm themed the delay of gratification test, and cognitive inhibition with an object discrimination paradigm called the reversal learning test. Aggressive reactivity was assessed with a standardized aggression-eliciting behavior test. When comparing police and privately owned dogs, police dogs showed higher aggression levels and poorer self-control, while the two groups did not differ in cognitive inhibition. Regardless of the dog group, the main results indicated impairments in self-control in dogs with high levels of aggressive reactivity. Dogs showing biting behavior had worse self-control abilities compared to dogs with no signs of aggression. No association between cognitive inhibition and aggression was found. We conclude that self-control, measured as the ability to tolerate delayed rewards, appears to be an important aspect of inhibitory control involved in the tendency to respond aggressively, particularly in police dogs.
... Where size is not a factor (i.e., Pit Bull Terrier versus Golden Retriever), one could theorize that genetic predisposition might play a role in the incidence of behavioral problems. However, while there is certainly a genetic contribution to behavior [60] and specific breeds might be over-represented for behavioral phenotypes [61,62], it is important to avoid placing too much emphasis on breed as a sole risk factor [63,64]. ...
The purpose of this retrospective case study was to evaluate trends over time in case distribution, sources, and breeds of dogs presenting to the behavioral medicine service at a veterinary college referral hospital in the United States. For case distribution and sources, the available records from the behavior service (n = 1923) from 1997 to 2017 were evaluated. Breeds of dogs presenting to all services (n = 51,052) were compared to behavior cases (n = 822) from 2007 to 2016. Over twenty years, 72.2% of dogs presented for aggression, 20.1% for anxieties/fears/phobias, and 7.4% for miscellaneous behavioral problems. Dogs acquired from breeders decreased and dogs from shelters, rescues, or adopted as a stray increased over twenty years (p < 0.0001). The Herding (p = 0.0124) and Terrier (p < 0.0001) groups were overrepresented for behavior problems as compared to all other services over ten years. Variations in terminology and diagnostic approach made comparisons with earlier studies difficult, which underscores a need for a more consistent methodology in veterinary behavioral medicine. Understanding trends in sources of dogs could direct resources aimed at guiding owners when acquiring a pet dog and preventing behavioral problems. Findings related to breeds could help guide research focused on the genetic contributions to behavior.
... It is important to highlight the common perception of camel herders that animals with a variable proportion of white fur (piebaldness) are the least aggressive but also the most fearful and submissive [89], which impairs their individual ability to lead collective actions. The same conclusion has been reached in dogs [78,90] and foxes [91] in domestic settings. ...
Simple Summary
Genetic selection of camels for behavioral traits is not an extended practice in livestock scenarios. Given the existence of pleiotropic genes that influence two or more seemingly unrelated phenotypic traits, here we studied the sociodemographic, zoometric and phaneroptical characteristics potentially determining the intraherd leadership role in Canarian camels. This local endangered breed is mainly reared in same-sex groups because of biased morphostructural preferences, that is, tourism/leisure and milk production for males and females, respectively. The attribute most influencing leadership role was sexual status, as gelded animals more frequently initiated group movements. Furthermore, younger camels were mainly endorsed as group leaders, a condition that could be ascribed to their recognized fluid intelligence and need for constant social and environmental interaction. Referring to zoometrics and phaneroptics, the heaviest and darkest-coated dromedaries were significantly more prone to reaching higher positions in the leadership hierarchy. The presence of white-haired zones in the extremities, head and neck as well as iris depigmentation had non-negligible influence on this type of social organization. This information is valuable for application both in refining animal handling procedures and in genetic selection of animals for their social behavior.
Abstract
Several idiosyncratic and genetically correlated traits are known to extensively influence leadership in both domestic and wild species. For minor livestock such as camels, however, this type of behavior remains loosely defined and approached only for sex-mixed herds. The interest in knowing those animal-dependent variables that make an individual more likely to emerge as a leader in a single-sex camel herd has its basis in the sex-separated breeding of Canarian dromedary camels for utilitarian purposes. By means of an ordinal logistic regression, it was found that younger, gelded animals may perform better when eliciting the joining of mates, assuming that they were castrated just before reaching sexual maturity and once they were initiated in the pertinent domestication protocol for their lifetime functionality. The higher the body weight, the significantly (p < 0.05) higher the score in the hierarchical rank when leading group movements, although this relationship appeared to be inverse for the other considered zoometric indexes. Camels with darker and substantially depigmented coats were also significantly (p < 0.05) found to be the main initiators. Routine intraherd management and leisure tourism will be thus improved in efficiency and security through the identification and selection of the best leader camels.
... Dogs are also occasionally neutered due to problem behaviors, such as male aggression. Some of these behavior problems (e.g., aggression) may also be linked to impulsivity or persistence [10][11][12]14,70,71], which may further complicate the picture. ...
Simple Summary
Various behavioral differences exist between male and female dogs, but very little research has focused on how sex influences cognition. Even fewer studies have taken sex hormones into account. Our aim was to investigate whether dogs’ sex and neutering status can influence two important cognitive traits: inhibitory control and social cognition. Inhibitory control was assessed using the cylinder test. In this task, the dog is required to inhibit reaching for a treat directly through a transparent barrier, and instead go around the barrier to access the treat. Social cognition was assessed using the unsolvable task, during which a food reward is visible but impossible to access. Dogs have three opportunities for action in this situation: (a) persisting with the problem independently, (b) seeking attention from a human, or (c) abandoning the task. Males were more impulsive and independent compared to females, whereas females had greater inhibitory control and were more likely to gaze at a human during a problem-solving situation. Since neutering status did not affect the results, it seems likely that these sex differences arose during early development and were not affected by levels of circulating sex hormones to a great extent.
Abstract
Sex differences in a variety of cognitive traits have long been reported in various species, including dogs. However, only a few canine studies have taken the possible effect of reproductive hormones into account. The aim of this study was to investigate the effects of sex and reproductive status of pet dogs (N = 1032) on two cognitive traits: inhibitory control and social cognition. Inhibitory control was assessed using the cylinder test, and the dogs’ tendency to initiate social contact with a human during a problem-solving situation was assessed using the unsolvable task. Female dogs had a significantly higher success rate in the cylinder test compared to males, and they spent significantly more time in human-directed behavior during the unsolvable task. In contrast, males spent significantly more time in independent behavior during the unsolvable task. Reproductive status had no significant effect on the results of the cylinder test or the unsolvable task. Our results showed that female dogs asked for more help/used a more cooperative strategy during a problem-solving situation and had greater inhibitory control compared to males. According to our results, it seems likely that these sex differences were not influenced to a large extent by reproductive hormones.
... Such behaviors are considered problematic if they pose a nuisance or a danger to household members [2]. In turn, behaviors that are unacceptable for dog owners are described as undesirable, even if they are consistent with an animal's ethogram of normal behavior [3][4][5]. Examples of undesirable behavior include excessive activity, excitation, vocalization or unprovoked aggression [6,7]. Stereotypies are repetitive, constant acts that serve no obvious purpose [8]. ...
Simple Summary
Abnormal, repetitive behaviors often pose a problem for dog owners. Such behaviors are considered undesirable if they pose a nuisance or a danger to humans. This study aimed to identify factors (breed, sex, origin, housing conditions) and situations that contribute to undesirable behaviors, such as aggression towards humans and other dogs/animals, separation anxiety, excessive vocalization, and oral and locomotion behaviors in the ancient dog breeds Akita, Alaskan Malamute, Basenji, Samoyed and Siberian husky. Undesirable behaviors were analyzed based on the results of a survey involving dog owners. Undesirable behaviors were most frequently reported in Akitas, Siberian huskies and Samoyeds, and they were more prevalent in males than in females and dogs living indoors with or without access to a backyard. Aggressive behaviors towards other dogs and animals, excessive vocalization and undesirable motor activities posed the greatest problems in ancient dog breeds.
Abstract
Abnormal repetitive behaviors often pose problems for dog owners. Such behaviors are considered undesirable if they pose a nuisance or a danger to humans. Ancient dog breeds are intelligent, sociable, active, boisterous and need regular outdoor exercise, but are also independent and reluctant to follow commands. This study aimed to identify factors (breed, sex, origin, housing conditions) and situations that contribute to undesirable behaviors, such as aggression towards humans and other dogs/animals, separation anxiety, excessive vocalization, and oral and locomotion behaviors in Akita, Alaskan Malamute, Basenji, Samoyed and Siberian husky. Undesirable behaviors in dogs were analyzed based on the results of 897 questionnaires. Breed influenced aggressive behavior towards other dogs/animals, aggression towards humans, undesirable oral and locomotion behaviors, and excessive vocalization. Aggressive behaviors were more prevalent in females than in males. Housing conditions were linked with aggression towards other dogs/animals, aggression at mealtime, and excessive vocalization. Undesirable behaviors were most frequently reported in Akitas, Siberian huskies and Samoyeds, and they were more prevalent in males than in females and dogs living indoors with or without access to a backyard. Aggressive behaviors towards other dogs and animals, excessive vocalization and undesirable motor activities posed the greatest problems in ancient dog breeds.
... En revanche, pour les six études suivantes, les races ou types raciaux étudiés sont comparés à l'effectif de la ou des races étudiées dans la population générale canine d'un pays durant une période donnée (effectif rapporté par les auteurs). L'étude de Amat et al. (2009) rapporte que les cockers spaniels anglais expriment plus de comportements d'agression envers leurs propriétaires que les autres races. indiquent que les races croisées sont les plus représentées parmi les chiens mordeurs de leur étude s'intéressant à 251 cas de morsures par agression de protection de ressources et 2 600 cas contrôles. ...
Advice of the French Food Safety Agency on the risk of dog bites and the relevance of breed specific laws made by a subgroup of the Animal Health and Welfare Committee. An evaluation of risk process : identification of the hazard, evaluation of risk i.e emission X expostion and consequences. Advice given on demand of Department of Agriculture related to Laws of 1999, 2007 and 2008 concerning dangerous dogs. Relevance of categorization of dog breeds is discussed as well as the methods of behavioural evaluation.
... The capacity for the CBD103 gene to competitively bind other melanocortin receptors (Candille et al., 2007) that modulate aggressive behaviour (Ducrest et al., 2008) may decrease aggression in melanistic wolves. Support for this mechanism comes from evidence that black-coated dogs have lower aggression rates than nonmelanistic dogs (Amat, Manteca, Mariotti, Torre, & Fatjo, 2009;Houpt & Willis, 2001). ...
Aggression is a quantitative trait deeply entwined with individual fitness. Mapping the genomic architecture underlying such traits is complicated by complex inheritance patterns, social structure, pedigree information and gene pleiotropy. Here, we leveraged the pedigree of a reintroduced population of grey wolves (Canis lupus) in Yellowstone National Park, Wyoming, USA, to examine the heritability of and the genetic variation associated with aggression. Since their reintroduction, many ecological and behavioural aspects have been documented, providing unmatched records of aggressive behaviour across multiple generations of a wild population of wolves. Using a linear mixed model, a robust genetic relationship matrix, 12,288 single nucleotide polymorphisms (SNPs) and 111 wolves, we estimated the SNP‐based heritability of aggression to be 37% and an additional 14% of the phenotypic variation explained by shared environmental exposures. We identified 598 SNP genotypes from 425 grey wolves to resolve a consensus pedigree that was included in a heritability analysis of 141 individuals with SNP genotype, metadata and aggression data. The pedigree‐based heritability estimate for aggression is 14%, and an additional 16% of the phenotypic variation was explained by shared environmental exposures. We find strong effects of breeding status and relative pack size on aggression. Through an integrative approach, these results provide a framework for understanding the genetic architecture of a complex trait that influences individual fitness, with linkages to reproduction, in a social carnivore. Along with a few other studies, we show here the incredible utility of a pedigreed natural population for dissecting a complex, fitness‐related behavioural trait.
... Our findings did not assess whether the Cocker Spaniels in the study were classified as having 'rage syndrome' but it is known that there is a genetic component to this UB (Podberscek & Serpell 1996). It has also been shown that Cocker Spaniels are one of the breeds that are most represented in attacks on humans, along with terrier breeds (Amat et al 2009). Although science has shown correlations between individual breeds and certain behav- iours, much of the information, especially regarding aggres- sion, has come from reports based on bite statistics which could be biased due to increased risk of injury from larger dogs (Duffy et al 2008) and therefore it is important to remember that every dog is an individual. ...
Undesirable behaviours (UBs) are common in dogs and can jeopardise animal and human health, leading to dog abandonment and euthanasia. Dogs exhibiting UBs may have compromised welfare from underlying emotional motivations for the behaviour (eg anxiety) or from the methods used by owners to resolve the problem (eg aversive techniques). The objective of this study was to estimate proportional mortality due to UBs and risk factors for death due to UBs, including death from road traffic accidents, in dogs under three years of age attending primary-care veterinary practices in England from 2009-2014. Cases were identified by searching de-identified electronic patient records from primary-care veterinary practices participating in the VetCompass Programme. The findings highlight that dogs under three years of age are at a proportionately high risk of death due to UBs (33.7%) compared with other specific causes of death (eg gastrointestinal issues: 14.5%). Male dogs had 1.40× the odds of death from UB compared with females. The proportional mortality from UB for male dogs where information on the cause of death was available was 0.41. Neutered dogs had 1.94× the odds of death due to a UB compared with entire dogs. Aggression was the most prevalent UB overall. Veterinarians had recommended referral in 10.3% of cases where dogs died due to exhibiting a UB and had dispensed nutraceutical, pheromone or pharmacological treatment to 3.0% of the UB cases that died. This study shows that undesirable behaviours require better preventive measures and treatment, through further research and education of veterinarians, other professionals within the dog industry and owners.
... In Labrador Retrievers, chocolate dogs were more "agitated when ignored" and showed more "excitability" than black dogs, and lower "trainability" and "noise fear" than both yellow and black dogs (Lofgren et al., 2014). In English Cocker Spaniels, solid-colored dogs were rated as more aggressive than parti-colored dogs, and red and golden dogs were found to be more aggressive than black dogs (Amat, Manteca, Mariotti, de la Torre, & Fatjo, 2009;Perez-Guisado, Lopez-Rodriguez, & Munoz-Serrano, 2006;Podberscek & Serpell, 1996). Fawn-colored Korean Jindo dogs were found to be less fearful and display less submissive reactivity than white dogs (Kim et al., 2010). ...
Coat color influenced the likelihood of a dog being reclaimed from a shelter as well as the length of stay (LOS) of abandoned dogs at the shelter. The shortest LOS was found in brindle and multicolor dogs (median time until adoption: 17 and 18 days, respectively) followed by white, fawn, red, brown, black and tan, and grey dogs. Black dogs had the greatest LOS (median 32 days). In lost dogs, coat color had no significant effect on the time spent at a shelter, the median time until a dog was reclaimed by his/her caretaker being one day, irrespective of the coat color. However, the results of our study suggest that black, brown, and brindle dogs are more likely to be abandoned by their caretakers, and that fawn, black and tan, grey, and red dogs, if lost, have a better chance of being reclaimed by their caretakers.
... 3 Some dogs can react aggressively with no obvious warning signs. 13 Team members should be educated about signs of stress in dogs and steps they can take to avoid eliciting aggression or fear. 1 2 d Food rewards can be given through the muzzle. Gaps in the muzzle can be enlarged so rewards can be given more easily. ...
... Therefore, the aptitude for wild boar hunt in IMSH is not influenced by the colour of coat. Differently, a relationship between coat colour and aggressive behaviour in the case of English cocker spaniels, where animals with a solid coat colour show higher levels of aggression than those that are parti-coloured (Podberscek & Serpell 1996P erez-Guisado et al. 2006;Amat et al. 2009). Also Kim et al. (2010) reported behavioural differences between fawn and white coat Jindo dogs. ...
This study aimed to evaluate the effect of four non-genetic factors (sex, coat colour, competition judges, type of trial) on the five hunting traits (search, approach, tracking of prey, standstill barking and physical skills) used to estimate the aptitude for wild boar hunt in Italian Maremma Scent Hound. A total of 1147 dogs (734 males, 399 females, and 14 not sexed dogs) were evaluated in competitions held in North-Central Italy, from 2010 to 2011. Dogs were tested as individuals, pairs and packs. Coat colour had no effect on the five tested traits. A significant difference (p < 0.01) between males and females was observed only for search. Type of trial had a significant effect (p < 0.01) on all the five hunting traits. Judges factor was significant (p < 0.01) for physical skills and barking remaining firm in place. A significant positive phenotypic correlation was observed among tracking of prey, approach and physical skills (p < 0.01). Approach and physical skills were positively correlated with approach (p < 0.05) and tracking of prey (p < 0.01). Search was negatively correlated with all the other four, whereas standstill barking showed no correlation with any traits. These data are the basis to improve our knowledge about the values of variability in considered hunting traits and they provide genetic criteria to the breeders to achieve more stringent selective choices.
... Fawn-colored Korean Jindo dogs exhibited significantly less fearful and submissive reactivity, and significantly more scentmarking behavior, than white-colored Jindos (Kim et al., 2010). Using the Campbell Test, aggression was found to be decreasingly likely in golden, black, and particolored Cocker spaniels (Amat et al., 2009). The likelihood of success in guide dog training was significantly different between black and yellow Labrador retrievers (Batt et al., 2008). ...
In this study, behavioral characteristics in purebred cats were hypothesized to associate with breed, eye color, coat color, and coat pattern. Owners of 574 single breed, registered cats completed the Feline Behavioral Assessment and Research Questionnaire (Fe-BARQ), which generates a standardized behavioral profile incorporating 20 factors. Subjects were also screened for evidence of fear-related aggression, territorial aggression and inappropriate social skills, fear of noises, redirected aggression, separation-related problems, and inappropriate elimination. Subject breeds included Abyssinians, Bengals, Birmans, Burmese, Devon rexes, Maine coons, Norwegian forest cats, Orientals, Persians, Ragdolls, Siamese, and Tonkinese. Coat colors included agouti, black, brown, cinnamon, blue, lilac, fawn, caramel, taupe, red, cream, blue cream, apricot, and white. Phenotypic variants associated with albinism, tabby and tortoiseshell patterning, inhibition of melanin, production of phaeomelanin, and white spotting were represented. Statistical analysis revealed significant differences in the Fe-BARQ scores and frequency of behavior problems in cats of multiple coat colors, coat patterns, and breeds (P < 0.05). Interestingly, nearly all associations between behavior and coat type could be attributed to breed-based behavior differences. Associations independent of breed included increased cat aggression in agouti cats and prey interest in red cats, decreased stranger-directed aggression in piebald cats, and increased likelihood of separation-related problems in Siamese and Tonkinese patterned cats.
... There is evidence that this trait is stable in humans, dogs and other animals [1][2][3][4] . In dogs, impulsivity has been considered largely in relation to aggressive behaviour 5 , with higher levels of impulsivity associated with low levels and poor regulation of serotonin and dopamine 6 . In humans, it is related to violent behaviour and behavioural disorders, such as attention deficit hyperactivity disorder (ADHD) 1,7 . ...
Impulsiveness describes the inability to inhibit behaviour in the presence of salient cues. Trait-level impulsivity exists on a continuum and individual differences can be adaptive in different contexts. While breed related differences in behavioural tendency in the domestic dog (Canis familiaris) are well established, the phenomenon within lines of a breed which have been selected more recently is not well studied, although it may challenge the popular notion of breed-typical behaviour. We describe differences in impulsivity between and within two dog breeds with working and show lines selected for different levels of impulsivity: Border Collies (herding work) and Labrador Retrievers (gun work). Recent show line selection might have lessened differences in impulsivity between breeds. We tested this hypothesis on a dataset of 1161 individuals assessed using a validated psychometric tool (Dog Impulsivity Assessment Scale - DIAS). Collies were more impulsive on average, consistent with the original purpose of breed selection. Regarding line, working Collies differed from working Labradors, but show lines from the two breeds were not significantly different. Altered or relaxed artificial selection for behavioural traits when appearance rather than behaviour become the primary focus for breeders may reduce average differences in impulsivity between breeds in show lines.
... Many scientists are actually looking for other parameters to use in the diagnosis of canine aggression as the detection of specific neurotransmitters in cerebrospinal fluid or blood that permit direct therapeutic interventions tailored to individual neurobiological needs. As an example, Amat et al. (2009) indicate that aggressive English cocker spaniels have lower serum serotonin than do aggressive dogs of other breeds that could explain why they seem to be more likely to show impulsive aggression when compared to other breeds. Another methods are the use of medical imaging where serotonin receptors, serotonin transporters, dopamine transporters, and other functions can be shown by scans, often combined with perfusion (Vermeire et al., 2011;Peremans, et al., 2002) and neuroimaging of serotonin 2A receptors as a valid biomarker for canine behavioral disorders (Vermeire et al., 2011). ...
... A subset of these dogs manifest sudden, explosive aggression either without an apparent trigger or grossly disproportionate to the stressor. This form of canine aggression shares similar characteristics to intermittent explosive disorder in humans 17 and has been variously called "idiopathic aggression" 45 ; "impulsive aggression" 46 ; "impulse-control aggression" 47 ; or, colloquially, "rage syndrome." 48 The prognosis for dogs exhibiting this form of aggression is extremely guarded to grave. ...
This article reviews the various causes of human-directed aggression in dogs and provides a step-by-step plan guiding the general practitioner through history taking, behavior observations, diagnosis, consultation, treatment, and follow-up care. Charts summarizing how to obtain behavioral information, the client's management options, treatment recommendations, diagnosis and treatment of human-directed aggression, and the clinician's role in preventing human-directed aggression are included. A graphic illustration of canine body language is also provided.
... Estas diferencias, pueden ser debidas a las diferencias regionales y culturales. El hecho de que la raza Cocker tienda a ocupar el primer lugar en agresividad hacia personas dentro de las consultas de etología clínica, y que ocupe el segundo lugar en el factor de riesgo, luego del Rottweiler, coincide con reportes internacionales (Amat, Manteca, Mariotti, Ruiz de la Torre & Fatjó, 2009;Beaver, 1983;Blackshaw, 1991;Fatjó et al., 2007;Pageat, 1998;Podberscek & Serpell, 1996;Scott & Fuller, 1965;Wright & Nesselrote, 1987). Por otro lado, la raza Cocker no aparece en forma frecuente en los registros del SAM-MSP. ...
... If we consider, however, that spaniels are also part of this breed-group and, for example, the English Cocker Spaniel (which comprise nearly one-third of our sample) is prone to show problem behaviours (e.g. Amat et al., 2010) our result may not come as a surprise. In parallel, more and more attention (and increased empathy) is being paid to mixed-breed dogs. ...
In this paper we present a novel adjective-based dog personality questionnaire, which was successfully implemented to characterise the behaviour of individual dogs. The scales obtained by Principal Component Analysis (Stranger-directed Sociability, Activity, Aggressiveness and Trainability) correspond well with the results of other studies published earlier. The obtained personality scales were also used to compare breed-groups registered in Fédération Cynologique Internationale (FCI) and a distinct group of mongrels was also included in the total sample (N = 352 dogs). Results suggest that in the case of pet dogs there are only slight detectable differences in personality dimensions between breed-groups and breeds. Furthermore, the present investigation also includes the comparison of two breeds, the Hungarian Vizsla and the German Shepherd Dog. After matching for demographic differences, we could not reveal differences in personality traits between the two breeds kept as pets. These observations caution against making hasty claims about the presence or absence of breed differences because environmental factors can mask, or even enhance potentially existing genetically potentiated breed differences.
Aggression is the most common dog behavioral problem, with important implications for public health. The aim of this study was to determine the perception of veterinarian clinicians of Montevideo regarding canine aggression, the sex effect, and the main breeds involved. One hundred veterinary clinics of Montevideo city were randomly selected to complete a survey about aggressiveness in dogs. Most veterinarians opined that males are more involved than females in canine aggression and that the Pit bull, the German Shepherd, and Uruguayan Cimarron breeds were the most involved in both types of aggression considered (between canines and towards people), while the Cocker Spaniel breed was involved in aggression towards humans and the Rottweiler breed in aggression between dogs. This work highlights that both veterinarians and other experts within the community identify the Uruguayan Cimarron as being aggressive, which indicates that the behavior of this breed may be of particular concern.
The optimal mixture of NaCl, KCl, MgCl2 and CaCl2 for obtain salted meat of chigüire with determined physical-chemical and sensory characteristics was obtained. The meat was cut into pieces and was salted for four days using different mixtures, according to a D-optimal design mixtures. After the salting, the moisture content (Xa), salt (Xs), sodium content (XNa), potassium content (Ka), magnesium content (XMg), calcium content (XCa), ashes content (XC), acceptance by flavor (Sa), acceptance by texture (Tex) and overall acceptance (A) were determined in the different samples. Also the yield (Y) of salting was calculated. Mathematical models fitted to data explained from 78.41 to 99.24% of the variation in the response variables, with a probability of 95%. Numerical and graphical methodologies determined the optimum composition of mixture as 0.47 g NaCl/g; 0.25 g KCl/g; 0.20 g MgCl2/g and 0.08 g CaCl2/g and the salted meat will have 0.25 g water/g; 0.48 g NaCl/g; 22621 mg sodium/kg; 15416 mg potassium/kg; 13732 mg magnesium/kg; 7392 mg calcium/kg, 4.2 (neither like or dislike); 4.9 (like) and 4.2 (neither like or dislike), respectively. Sensory acceptance indicated the need to obtain descriptors that characterize the product and allow a subsequent improvement of the composition of the mixture.
Dogs have an ever-increasing presence in our lives from being a child’s best friend to detecting roadside bombs to guiding people with visual impairments. Examining the personalities of these animals can help us to better understand them. This chapter reviews many topics related to dog personality, beginning by examining the structure of dog personality. Studies have found that dog personality consists of two to more than five dimensions with little consensus as to the optimal number of dimensions needed to best describe dog personality. This chapter then examines the reliability and validity of dog personality assessments. Finally, this chapter reviews the evidence for various genetic, biological, and environmental factors related to dog personality and concludes that what we currently know is largely mixed. Future studies on dog personality should further examine several personality dimensions and factors likely associated with dog personality.
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.
This clinical forum discusses a real-life behavioural case history of canine resource guarding, conducted by the lead author. The case highlights the importance of consulting directly with the client and viewing the dog within the home environment, and the complexity and challenges that each individual case presents. A summary of the case was presented to three animal behaviourists, together with a series of questions.
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.
The authors explored a possible relationship between coat color and aggressive behaviors in the domestic cat. This study used an Internet-based survey to collect information on coat color, affiliative behaviors toward cats/humans, agonistic behaviors toward cats/humans, other "problem" behaviors, and cat and guardian demographic data. A total of 1,432 cat guardians completed the online survey; after exclusions based on study protocol, data analysis included 1,274 completed surveys. Guardians reported sex-linked orange female (tortoiseshells, calicos, and "torbies"), black-and-white, and gray-and-white cats to be more frequently aggressive toward humans in 3 settings: during everyday interactions, during handling, and during veterinary visits. Kruskal-Wallis 1-way analysis of variance was used to compare possible differences between the 2 sexes and among different coat colors. Analyses of aggression due to handling, as well as aggression displayed during veterinarian visits, showed little difference among coat colors in these settings.
Associations between mammalian coat color and behavior have been investigated in a number of species, most notably the study of silver foxes by the Institute of Cytology and Genetics at the Russian Academy of Sciences. However, the few studies conducted regarding a potential relation between coat color and domestic cat personality have shown mixed results, even though many people believe that differently colored cats have distinct personalities. Understanding how humans might perceive personality in relation to coat color may have important ramifications regarding whether cats are relinquished to shelters or adopted from them. In order to assess human perceptions of differently colored cats, we conducted an anonymous, online survey, using a 7-point Likert scale and 10 terms describing personality traits that were chosen based on previous studies of animal personality. This survey examined how people assigned these given terms (active, aloof, bold, calm, friendly, intolerant, shy, stubborn, tolerant, and trainable) to five different colors of cats (orange, tricolored, white, black, and bi-colored). There were significant differences in how participants in this study chose to assign personality terms to differently colored cats. For example, participants (n = 189) were more likely to attribute the trait “friendliness” to orange cats, “intolerance” to tri-colored cats, and “aloofness” to white and tri-colored cats. No significant differences were found for “stubbornness” in any colors of cats. White cats were seen as less bold and active and more shy and calm than other colors of cats. While survey respondents stated that they placed more importance on personality than color when selecting a companion cat, there is some evidence that they believe the two qualities are linked. We anticipate our findings will be relevant to further study in domestic cat personality and to those who work in animal rescue, particularly in how shelters promote differently colored cats and educate potential adopters.
The agouti locus influences coat color by antagonizing melanocyte-stimulating hormone (MSH) at its receptor on pigment cells and may antagonize MSH in neural tissue. This study replicates work on rats to assess whether behavioral (neural) effects of the agouti locus are as similar across mammals as those on coat color. Handling, open-field, platform jump, and food-novelty tests were conducted on agouti and nonagouti deer mice (Peromyscus maniculatus) following protocols in C. A. Cottle and E. O. Price (1987). As with rats, nonagouti deer mice were less aggressive, less active, and easier to handle compared with their agouti counterparts. Nonagouti deer mice also groomed more than agouti subjects. Thus, behavioral effects of the agouti locus are conservative, and agouti may be an important modulator of melanocortins in neural as well as integumentary tissue.
The objective of the present study was to determine the extent to which the nonagouti pelage-color allele influences selected behaviors (including docility) of the wild Norway rat. Agouti and nonagouti (black) littermates were compared in tests for handling, open-field behavior, platform jumping, and response to a novel food item, all of which clearly differentiate wild and domestic rats. Nonagouti rats were significantly easier to approach, capture, and handle than their agouti sibs. However, differences between agouti and nonagouti rats for the other variables studied were not significant. Although the presence of the nonagouti allele cannot fully account for the behavioral differences between wild and domestic Norway rats, it may have facilitated the domestication of this species by improving ease of handling.
Despite the popular idea that dog owners are often responsible in some way for their animals' behaviour problems, the scientific evidence is scarce and contradictory. Some studies have failed to detect any links between the quality of the owner-dog relationship and the occurrence of behaviour problems, while others suggest that some behaviour problems may be associated with certain aspects of owner personality, attitudes and/or behaviour.Using retrospective data from a sample of 737 dogs, the present study investigated the association between the prevalence of different behaviour problems and various aspects of either owner behaviour or owner-dog interactions. A number of statistically significant associations were detected: (a) between obedience training and reduced prevalence of competitive aggression (P < 0.02), separation-related problems (P < 0.001), and escaping and roaming (P < 0.05); (b) between the timing of the dogs' meal times and the occurrence of territorial-type aggression (P < 0.01); (c) between sleeping close to the owner and increased prevalence of competitive aggression (P < 0.01) and separation-related problems (P < 0.01); (d) between first-time ownership and the prevalence of dominance-type aggression (P < 0.001), separation-related problems (P < 0.05), fear of loud noises (P < 0.001), and various manifestations of overexcitability (P < 0.001); (e) between owners' initial reasons for acquiring a dog and the prevalence of dominance-type (P < 0.001), competitive (P < 0.01) and territorial aggression (P < 0.01). The possible practical implications of these findings are discussed.
Behavioural problems directly affect the welfare of dogs and cats. The existence of a behavioural problem is a factor in the euthanasia and relinquishment of animals to shelters — a significant proportion of companion animals that are abandoned and euthanased are attributed to behavioural problems. Some behavioural problems are linked to stress and anxiety. In order to prevent and treat behavioural problems it is essential to have good epidemiological data. Most studies regarding the prevalence of behavioural problems use data from veterinary behaviourists. To our knowledge, no studies regarding the prevalence of small animal behavioural problems have been conducted in Spain. Therefore, a study was designed to estimate different aspects of canine and feline behavioural problems in Spain from the perspective of the veterinary practitioner. Of 433 valid questionnaires returned during a six month period, 46.2% of veterinarians referred cases to veterinary behaviourists and 12.3% to dog trainers; 34.7% never referred cases. Destructiveness, aggression and house soiling were the most frequent complaints regarding behavioural problems in dogs, whereas house soiling was clearly considered the main behavioural complaint in cats, followed by furniture scratching and excessive vocalisation. Behavioural modification was considered the most effective treatment for dogs, followed by drugs and castration. In cats the most effective treatment was castration, followed by drug therapy and behavioural modification.
A group of ‘low’ (n = 217) and ‘high’ (n = 218) aggression purebred English Cocker Spaniels were compared in relation to demographics and owner interactions. Owners of ‘low’ aggression dogs were more likely to be: older (65 years +; χ2 = 18.753, P < 0.01) and more attached to their dogs (U = 20346, P < 0.001). Dogs in the ‘high’ aggression group were: significantly more likely to be of a solid colour (χ2 = 38.13, P < 0.001); more likely to have been chosen for pet purposes only (χ2 = 25.161, P < 0.001); more likely to have suffered an illness during the first 16 weeks of life (χ2 = 14.899, P < 0.001); groomed less often (t = 2.252, P < 0.05); given less time for walks/exercise (t = 2.618, P < 0.01); slow in obeying commands (U = 17967.5, P < 0.001), more likely to pull on the lead (U = 16663, P < 0.001); and more likely to react to loud or high-pitched noises (χ2 = 14.142, P < 0.001). Factors often quoted to be important in the development of dominance-related aggression, such as feeding the dog before the owner eats, a lack of obedience training, and playing competitive games with the dog, were not found to be significantly different between the two groups. Determining the importance of various factors in the development of canine aggression will enable us to better advise owners in the rearing of their dogs.
Two thousand questionnaires were distributed randomly via the Kennel Club (UK) to owners of purebred English Cocker Spaniels (ECSs). Owners were asked to give details about the ECSs they owned: age, sex, neuter status, coat colour. They were also asked to indicate whether their dog showed aggression (on a 1–5 scale; 1, never or almost never; 5, always or almost always) in any of 13 situations. These were: aggression towards strange dogs (A1), towards strangers approaching the dog (A2), towards persons approaching/visiting the home (A3), towards persons approaching the owner away from home (A4), towards children in the household (A5), towards other dogs in the household (A6), when the owner gives attention to other person or animal (A7), toward owner or member of owner's family (A8), when disciplined (A9), when reached for or handled (A10), when in restricted spaces (A11), at meal times/ defending food (A12) and, suddenly and without apparent reason (A13).
Episodic dyscontrol (rage) was diagnosed from the clinical history, electroencephalographic findings, and response to oral treatment with phenobarbital in 3 dogs. Clinical features included a mood change heralding aggressive incidents, explosive aggression directed at people or objects, and a postaggressive phase characterized by lethargy and lack of responsiveness. Abnormal electroencephalographic findings included spike activity in the temporal recordings. All 3 dogs responded well to anticonvulsant medication with phenobarbital.
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.
The objective of the present study was to determine the extent to which the nonagouti pelage-color allele influences selected behaviors (including docility) of the wild Norway rat. Agouti and nonagouti (black) littermates were compared in tests for handling, open-field behavior, platform jumping, and response to a novel food item, all of which clearly differentiate wild and domestic rats. Nonagouti rats were significantly easier to approach, capture, and handle than their agouti sibs. However, differences between agouti and nonagouti rats for the other variables studied were not significant. Although the presence of the nonagouti allele cannot fully account for the behavioral differences between wild and domestic Norway rats, it may have facilitated the domestication of this species by improving ease of handling.
Using a computer-generated data base of rankings of 56 breeds of dogs on 13 behavioral traits, a factor analysis was performed to determine the extent to which a few general underlying behavioral tendencies are manifested in specific characteristics. Three factors, referred to as reactivity, aggression, and trainability, accounted for 81% of the variance in the 13 behavioral traits. Subsequently, a cluster analysis was performed to generate 7 clusters of dog breeds on the basis of similarity in scores for each of the 3 main factors. The clusters reflected to some degree the conventional groupings of dogs into working, sporting, hound, and terrier breeds. A quantitative analysis of the ranking of male dogs vs female dogs for the 13 characteristics revealed that males differed from females on 10 traits. It was concluded that these gender and cluster profiles will allow people to select a breed or gender of dog that is most likely to match the emotional and physical needs of the person who will provide a home for the pet.
Establishing a prognosis for dogs with dominance-related aggression is difficult. Some dominant-aggressive dogs respond well to treatment; others continue to be serious risks for their owners. A study was performed to identify characteristics of dominance-related aggression and to identify risk factors associated with whether the aggressive behavior led to euthanasia. Medical records of 110 dogs with dominance-related aggression were examined retrospectively; characteristics of owner-directed aggression and eventual outcome of the dogs were recorded. By means of logistic regression, 2 different models were found to describe the association between behavior characteristics and outcome. In the first model, severe aggression in response to benign dominance challenges and body weight > 18.2 kg were associated with outcome. In the second model, unpredictability of aggression and a history of being purchased were associated with outcome. We concluded that dominance-related aggressive behavior can be subclassified according to severity and type and that outcome (ie, euthanasia) may be predictable in some cases.
To determine the success rate of positive training methods and behavioral modification techniques in dogs with dominance aggression and to compare personality profiles between owners of dominant-aggressive and nondominant dogs.
Prospective clinical study.
10 dominant-aggressive dogs and 10 non-dominant, nonaggressive control dogs.
Dominance aggression was quantified, using an aggression score, in the 10 dominant dogs before and after a nonconfrontational behavior modification program. The personality profile of the owners of dominant and control dogs, assessed by means of a Keirsey temperament sorter, was compared, as was the influence of owner personality on the outcome of behavioral modification in the dominant dogs.
9 of 10 dominant dogs responded to the nonconfrontational treatment program by a decrease in aggressive response to similar eliciting stimuli. Significant differences were not found between the personality of the owners of dominant versus control dogs, and owner personality did not significantly affect the outcome of behavior modification treatment.
Nonconfrontational behavior modification programs are effective in reducing owner-directed dominance aggression in dogs. Owner personality does not necessarily predispose certain individuals to assaults by dominant dogs or profoundly affect their ability to engage in a successful behavioral modification program.
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.
The D4 dopamine receptor (D4DR) polymorphic region, which is possibly related to the personality trait known as novelty seeking in humans, was examined in 34 dogs from two breeds (Golden retriever and the Japanese indigenous breed, Shiba) by the polymerase chain reaction (PCR), and the DNA sequences of each allele were determined. The polymorphic region of the dog D4DR gene was composed of 39- and 12- base pair (bp) units, and four alleles (A-D) were identified based on the number and/or order of these units. Intra- and inter-breed allele variations were observed. The frequency of the short A allele was dominant (78.9%) in the Golden retriever, while the long D allele was most common (46.7%) in the Shiba. These findings suggested that the allele frequency varied significantly between different breeds, and that analysis of the polymorphism in D4DR might be of use for understanding the behavioral traits of dogs.
Background
Atrial fibrillation (AF) is an important independent risk factor for stroke. Randomised controlled trials have shown that this risk can be reduced substantially by treatment with warfarin or more modestly by treatment with aspirin. Existing trial data for the effectiveness of warfarin are drawn largely from studies in selected secondary care populations that under-represent the elderly.
The Birmingham Atrial Fibrillation Treatment of the Aged (BAFTA) study will provide evidence of the risks and benefits of warfarin versus aspirin for the prevention of stroke for older people with AF in a primary care setting.
Study design
A randomised controlled trial where older patients with AF are randomised to receive adjusted dose warfarin or aspirin. Patients will be followed up at three months post-randomisation, then at six monthly intervals there after for an average of three years by their general practitioner. Patients will also receive an annual health questionnaire.
1240 patients will be recruited from over 200 practices in England. Patients must be aged 75 years or over and have AF. Patients will be excluded if they have a history of any of the following conditions: rheumatic heart disease; major non-traumatic haemorrhage; intra-cranial haemorrhage; oesophageal varices; active endoscopically proven peptic ulcer disease; allergic hypersensitivity to warfarin or aspirin; or terminal illness. Patients will also be excluded if the GP considers that there are clinical reasons to treat a patient with warfarin in preference to aspirin (or vice versa).
The primary end-point is fatal or non-fatal disabling stroke (ischaemic or haemorrhagic) or significant arterial embolism. Secondary outcomes include major extra-cranial haemorrhage, death (all cause, vascular), hospital admissions (all cause, vascular), cognition, quality of life, disability and compliance with study medication.
Aggressive behavior induces an adrenocortical stress response, and sudden stressors often precipitate violent behavior. Experiments in rats revealed a fast, mutual, positive feedback between the adrenocortical stress response and a brain mechanism controlling aggression. Stimulation of the aggressive area in the hypothalamus rapidly activated the adrenocortical response, even in the absence of an opponent and fighting. Hypothalamic aggression, in turn, was rapidly facilitated by a corticosterone injection in rats in which the natural adrenocortical stress response was prevented by adrenalectomy. The rapidity of both effects points to a fast, mutual, positive feedback of the controlling mechanisms within the time frame of a single conflict. Such a mutual facilitation may contribute to the precipitation and escalation of violent behavior under stressful conditions.
Dopamine and noradrenaline are catecholamine neurotransmitters that are produced by biosynthetic enzymes such as tyrosine hydroxylase (TH) and dopamine beta -hydroxylase (DBH). As a first step to elucidate the genetic background of canine behavioral traits, we selected these genes as targets and sequenced these canine genes, and found that both were highly homologous with those of human beings. Then brain cDNAs derived from ten unrelated Beagles were used to search for polymorphisms in these genes. Four single nucleotide polymorphisms (SNPs) (C97T, G168A, G180A and C264T), one of which (C97T) will cause amino acid substitution in the TH gene, and two SNPs (C789A and A1819G), both of which will cause amino acid substitutions in the DBH gene were identified. The allelic frequencies among five dog breeds (47 Golden Retrievers, 41 Labrador Retrievers, 40 Malteses, 26 Miniature Schnauzers, and 39 Shibas) were examined and found to have significant variation between them with regards to all these SNPs, except for C97T in the TH gene and A1819G in the DBH gene. The polymorphisms of C97T and A1819G were found only in the Shiba. The present results suggest that the polymorphisms of the genes encoding catecholamine biosynthetic enzymes may become important markers for examining the genetic background of behavioral characteristics in dogs.
To determine prevalence of owner-directed aggression and identify associated environmental and genetic factors in English Springer Spaniels.
Prevalence survey.
1,053 adult English Springer Spaniels.
A mail survey was sent to 2,400 randomly selected owners of adult American Kennel Club-registered English Springer Spaniels. Dogs with a history of aggression to family members and familiar humans were compared with dogs without such a history.
1,053 questionnaires (56.1% of the 1,877 delivered) were completed. A history of owner-directed growling or more intense aggression was reported in 510 (48.4%) dogs. Two hundred seventy-seven (26.3%) dogs had bitten a human in the past; 65.2% of bites were directed at familiar (owner or nonowner) adults and children. Variables associated with owner-directed aggression included sex of dog (male), neuter status (neutered, regardless of sex), show or bench lines, age > 4 years, aggression to unfamiliar adults and children, acquisition from a hobby breeder, less responsiveness to obedience cues, and a specific kennel and 1 popular sire from that kennel in a 4-generation pedigree.
Owner-directed aggression in adult English Springer Spaniels was associated with a number of environmental, sex-related, and inherited factors. To reduce the risk of aggression, prospective owners might seek a female, hunting-type English Springer Spaniel from an experienced breeder. However, because risk factors are broad and varied, there are limitations to the extent to which behavior can be predicted and further study is needed of the inheritance of aggression in this breed.
Excitatory amino acid transporters (EAATs) are important for terminating glutamatergic neurotransmission and protect central nervous system (CNS) neurons from glutamatergic excitotoxicity. We selected these genes as targets that may relate to canine behavioral traits. After screening four EAAT genes (glutamate transporter-1; GLT-1, excitatory amino acid transporter 4; EAAT4, excitatory amino acid carrier; EAAC1, glutamate/aspartate transporter; GLAST) for single nucleotide polymorphisms (SNPs), we identified two silent SNPs (C129T and T471C) in the GLT-1 gene. We genotyped 193 dogs of 5 breeds and found significant variation among breeds in these two SNPs in GLT-1. The C129T polymorphism was not observed in Malteses and Miniature Schnauzers. These results suggest that polymorphisms in the GLT-1 gene may be useful markers for examining how the genetic background relates to the behavioral traits of dogs.
To clarify the behavioral profiles of 56 pure breeds of dogs in Japan, 96 small-animal veterinarians participated in a questionnaire survey using the same criteria as in preceding studies conducted in the United States and the United Kingdom. We found significant differences among breeds in all behavioral traits examined. In addition, gender differences were revealed in terms of aggression to dogs, territorial defense, excitability, general activity, dominance over owner, destructiveness, watchdog barking, and snapping at children, which were all rated higher in males than females, whereas obedience training and housebreaking ease were rated higher in females. No gender differences were evident in playfulness, excessive barking, or affection demand. Using factor analyses, "aggressiveness", "reactivity", and "trainability" were determined to be consistent with results found in the US and UK surveys. On the basis of these factor scores, seven groups of breeds were determined by cluster analysis to compare to the US survey; 22 of the 38 breeds common with the US survey were categorized into the same groups as those in that survey. The results demonstrated differences in canine behavioral predisposition among breeds and between genders. The similarity in the results between our study and previous surveys, which involved distinct geographical locales, suggests that the genetic basis of breed-specific temperamental traits is manifested irrespective of the cultural or regional identities of the owners.
In its 18 chapters, this multiauthor book covers all major aspects of the genetics of horses from systematics and phylogeny to molecular genetics, and comprehensively surveys the literature of the past few decades. It is addressed to a wide readership from research workers to those concerned with more practical aspects of the breeding and keeping of horses. The book has both a glossary of terms and a subject index.
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. Language: en
A retrospective study was designed to assess the prevalence and clinical presentation of canine aggression problems in a referral practice in Spain. One thousand forty canine aggression cases seen at the Animal Behavior Clinic (Barcelona School of Veterinary Medicine) were analyzed. Each aggression problem was characterized according to 7 predefined diagnostic categories. Breed- and sex-related risk factors were calculated by comparing the aggressive dogs to a control population. Aggression problems were the most common behavior complaint (52.28% of all canine behavior cases). Complaints of owner-directed aggression were the most frequent (38.55%), followed by aggression toward other dogs (34.85%) and toward unfamiliar people (21.95%). A mean of 1.4 diagnoses of aggression per dog were established. Social conflict aggression toward family members was the most common diagnostic category (35.34%). Of the aggressive dogs, 69% were males and 31% were females, of which only 11% and 12% were neutered, respectively. Two breeds, the English cocker spaniel and the Catalan sheepdog, presented a particularly high risk for aggression in the studied population.
A total of 51 seven-week-old English Cocker Spaniel puppies were measured for dominant–aggressive behaviour using the Campbell Test. The dogs consisted of a F1 full sibs and half sibs from matings of 4 sires with 10 dams. The purpose of this study was to determine if the variability observed in this behavioural characteristic has an additive genetic component and if so, to estimate heritability (h2). Coat colour and sex were examined as fixed effects.According to the results of the study: (1) there are highly significant differences between sexes; with males being more dominant than females, regardless of coat colour; (2) there are highly significant differences in aggressive behaviour depending on coat colour with greater to lesser dominance found in golden, black and particolour coats in that order; (3) there is no interaction between sex and colour when exhibiting greater or lesser dominance; (4) heritability, estimated on sire components, is hS2=0.20, indicating that the variability observed in dominant–aggressive behaviour is in part due to genetic factors; and (5) heritability estimated on dam components is hD2=0.46, which implies that the maternal effect (genetic and environmental) is an important factor in this type of behaviour.It is concluded that there is an additive genetic, and therefore, hereditary factor for dominant–aggressive behaviour in the English Cocker Spaniel. Some of the fixed factors include: sex (males are dominant over females), coat colour (golden-coated are the more dominant dogs followed by the black-coated and finally by the particolour coat dogs) and the common environmental effect due to litter.
Dogs show considerable variation in morphology, genetics and behaviour caused by long periods of artificial selection. This is evident in the large number of breeds we have today. Behavioural differences among breeds have often been regarded as remnants from past selection during the breeds’ origin. However, the selection in many breeds has, during the last decades, gone through great changes, which could have influenced breed-typical behaviour. In order to investigate this, breed differences were studied using data from a standardized behavioural test from 13,097 dogs of 31 breeds from the Swedish dog population. Based on the test results, breed scores were calculated for four behavioural traits: playfulness, curiosity/fearlessness, sociability and aggressiveness. These traits have previously been found to be stable and valid, and hence regarded as personality traits in the dog. The present results suggested large differences between breeds in all of the investigated traits, even though there were within-breed variations. No relationships between breed-characteristic behaviour and function in the breeds’ origins were found. Instead, there were correlations between breed scores and current use of the breeding stocks, which suggest that selection in the recent past has affected breed-typical behaviour. The breeds’ use in dog shows, the dominating use in general, was negatively correlated with all investigated traits, both in sires and in dams. In contrast, use in Working dog trials was positively correlated with playfulness and aggressiveness in sires. Thus, these results suggest that selection for dog show use is positively correlated with social and non-social fearfulness, and negatively with playfulness, curiosity in potentially threatening situations and aggressiveness, whereas selection for Working dog use is positively correlated with playfulness and aggressiveness. Furthermore, correlation analyses show that popular breeds have higher sociability and playfulness scores than less popular breeds, suggesting that a positive attitude towards strangers is an important characteristic of a functional pet dog and desirable by dog owners. This indicates that selection towards use in dog shows may be in conflict with pet dog selection. Furthermore, these results suggest that basic dimensions of dog behaviour can be changed when selection pressure changes, and that the domestication of the dog still is in progress. A standardized behavioural test, like the one used in this study, is suggested to be highly useful as a tool in dog breeding programs.
Many of the structural modifications of modern breeds of domestic dog,Canis familiariscan be explained by changes in the rate of development, during domestication from the wolf,C.lupusThese changes have been dominated by paedomorphosis, or underdevelopment, so that the adult passes through fewer growth stages and resembles a juvenile stage of its ancestor. In this paper the effects of these processes on the signalling ability of 10 breeds selected for their degree of physical dissimilarity to the wolf are examined. The number of ancestral dominant and submissive behaviour patterns used during signalling within single-breed groups ranged from two (Cavalier King Charles spaniel) to 15 (Siberian husky), and this correlated positively with the degree to which the breed physically resembles the wolf, as assessed by a panel of 14 dog behaviour counsellors. When the signals displayed by each breed were grouped according to the stage of wolf development in which they first appear, those breeds with the smallest repertoires were found to draw most of their signals from those appearing before 20 days of age in the wolf, suggesting that physical paedomorphism has been accompanied by behavioural paedomorphism.
Concentrating on the importance of changes in mammal behaviour, morphology and coloration to the processes of domestication, this book discusses ways that feral, semi-domesticated and fully domesticted animals perceive, interpret and respond to their environment. The main chapters are on: diversity of appearance; origins; behavioural changes; stress; acquisition and processing of information; transmitter substances for information processing; coat colour and behaviour; coat colour selection; endurance limits; taming and return to the wild; new domestications; and domestication and evolution. -P.J.Jarvis
The records of dogs in an animal shelter in Chester County, PA were analyzed for a 3 1/2 year period to describe the canine population dynamics and to identify the risk factors for dogs' failure to be reclaimed and to be euthanized. Dogs ≥1 year of age accounted for the majority (72.5%) of incoming dogs. Forty-one percent of dogs received by the shelter were purebred. The six most common breeds were Labrador Retriever (14.6%), German Shepherd (9.8%), Golden Retriever (7.5%), Beagle (7.1%), Cocker Spaniel (5.5%), and Siberian Husky (5.3%), accounting for 50% of all incoming purebred dogs. Nearly one fifth (17.2%) of the live surrendered dogs were brought in by their owners specifically to be euthanized. A similar proportion (18.8%) of adopted dogs were returned to the shelter. Fifty-two percent of surrendered dogs and 77% of stray dogs were discharged alive from the shelter (53.8% of the stray dogs were returned to their owners). The reclaim rate was lowest (10.8%) for dogs < 4 months of age, and highest (68.8%) for dogs ≥10 years of age. Over two-thirds (67.7%) of purebred dogs were reclaimed by their owners, compared with 41.2% of mixed breed dogs. More purebred dogs were reclaimed the same day they were admitted than mixed breed dogs (46.1% vs. 38.0%). Approximately 60% of all stray dogs ≥1 year old were reclaimed each month while only 23.2% of dogs less than 1 year were reclaimed. Mixed breed dogs were 1.8 times as likely to be euthanized as purebred dogs. The risk of euthanasia increased with age for mixed breed dogs, but not for purebred dogs. Purebred dogs ≥3 years old were at an increased risk of euthanasia only when compared with dogs < 4 months of age. Of the dogs that were adopted, purebred dogs < 1 year of age spent fewer days (4.27) in the shelter than mixed breed dogs < 1 year (5.94), purebred dogs ≥1 year (5.92), or mixed breed dogs ≥1 year (10.06). Approximately one fifth (19.4%) of purebred dogs were adopted through a breed rescue group.
In the period 1987–1991 the consultant service established by the Danish Animal Welfare Society and the Danish Civil Dog Training Association reported 3975 problems in relation to pet dogs in Denmark. With nine categories of problem behaviour a total of 2719 problems were recorded in 2238 dogs. The data were analysed for the influence of breed, gender and age on the risk of developing behaviour problems. The analysis was designed as a case-control study using two control groups: (1) dogs registered by Danish Kennel Club in a 5-year period and (2) dogs treated at The Royal Veterinary and Agricultural University, Copenhagen, Denmark in a 4-month period. Thirteen breeds or breed groups including mixed breeds were compared with a reference group consisting of Labrador Retrievers. Compared with the reference group, Alsatians seemed to have higher risks of aggression towards other dogs, aggression towards strangers and general anxiety. For Cocker Spaniels higher risks of aggression towards the owner, aggression towards strangers and indoor urination/defecation were found. Collies seemed to have higher risks of aggression towards strangers, indoor urination/defecation and general anxiety. Furthermore, a higher risk of general anxiety was found in Poodles and Fox Terriers. Generally, Dachshunds, a group consisting of all terriers excluding Fox Terriers and mixed breeds, seemed to have a low risk of behaviour problems. Compared with females, males seemed to have a lower risk of general anxiety and a higher risk of problems related to lack of training and all kinds of aggression. About 80% of the behaviour problems were reported within the first 3 years of life. Only 5.5% of the dogs were suggested to be or were in fact euthanized.
During the 1986 National Health Interview Survey (NHIS), data on injuries resulting in a doctor visit or restricted activity for at least a half day were collected and assigned E-codes. Based on 603 injuries, the estimated number of nonfatal injuries for civilian, noninstitutionalized U.S. residents in 1986 was 60,212,000. The most frequent cause of injury was a fall (11,547,000), followed by motor vehicle traffic crashes (4,361,000) and adverse effects of drugs and biologics (3,363,000). While cause-specific detail was limited by small numbers of injuries in the sample, the NHIS can provide a valuable snapshot of the causes of nonfatal injuries.
One of the most frustrating problems for veterinarians is the animal with a recurring behavioral disorder that is apparently a seizure disorder. Similar human disorders have been shown to be caused, in most cases, by organic disease in the cerebrum. There are reports in the veterinary literature that appear to support the same theory; however, there is no well-designed study with adequate animal numbers that proves the syndromes to be the same as in human medicine. It is clear that much research needs to be done. Diagnostic work up should be done meticulously, with emphasis on looking for intracranial disease. Treatment with phenobarbital is recommended to control the seizures, although the results will be variable.
A frequency of more than 10(-2) of the de novo appearance of piebald spotting (star) was established in silver-black foxes selected for domestic behavior. The star phenotype is determined by the autosomal semidominant gene S. Ten genealogical groups of foxes, in which star arose independently, were analyzed. Of these, the star character is determined by S alleles in at least seven groups. The S gene is located in a linkage group other than the earlier described W (Georgian white) locus. The star gene is incompletely penetrant, but its penetrance is significantly higher in offspring from tame mothers than from aggressive ones, or when S is received from a heterozygous vixen (Ss). There was a notable shortage of homozygous (SS) offspring from Ss X Ss crosses, which cannot be adequately explained by selective embryonic mortality, differential zygotic and gametic death, or transgression of homozygous and heterozygous phenotypes. Some foxes, proven carriers of a homozygous (Ss) genotype, showed the phenotype and mode of inheritance characteristic of heterozygotes (Ss). Presumably, the mechanism responsible of these observations is a heritable functional activation-inactivation of the star gene. Some implications of this concept in terms of destabilizing selection are discussed.
The purpose of this study was to examine the relationship between behavior and serotonin by using a nonhuman primate model of aggression and impulse control.
During a routine capture and medical examination, 26 adolescent male rhesus macaques (Macaca mulatta) were selected as subjects from a free-ranging population of 4,500 rhesus monkeys inhabiting a 475-acre sea island. Physiological data were obtained from 22-23 of the subjects. Blood and CSF samples were obtained, and each subject was fitted with a radio transmitter collar for rapid location. The subjects were released into their social groups, and quantitative behavioral observations were made over a 3-month period.
CSF 5-hydroxyindoleacetic acid (5-HIAA) concentrations were inversely correlated with "escalated" aggression, i.e., a measure of more intense or severe aggression as defined by the ratio of chases and physical assaults to all aggressive acts. CSF 5-HIAA concentrations were significantly lower in those subjects who showed evidence of physical wounding than in subjects with no wounds. Low CSF 5-HIAA concentrations were also correlated with greater risk-taking as determined by an analysis of leaping behaviors in the forest canopy. The ratio of long leaps (leaps that traversed the longest distances at dangerous heights) to all leaps was negatively correlated with CSF 5-HIAA concentrations.
Adolescent male rhesus macaques with low CSF 5-HIAA concentrations are at risk for 1) exhibiting more violent forms of aggressive behavior and 2) loss of impulse control as evidenced by greater risk taking during movement through the forest canopy.
Behavioral complaints reported from surveys of dog owners were compared with those from owners whose dogs were examined in referral behavior practices. Types of behaviors that dog owners considered to be problems varied from those only mentioned in surveys to those considered serious enough to seek professional help. The most common complaints listed by owners in surveys included territorial aggression, excessive protection of the owner, and excessive vocalization. Problems reported for referred behavior cases were aggression, especially dominance-related, and house soiling. Types of referral cases reported in the literature were similar to those examined at a university behavior clinic, but distribution of problems varied.
Aggression has been shown to be related to reduced serotonergic activity in humans and non-human primates, and in rodents. We now studied the relationship between cerebrospinal fluid (CSF) monoamine metabolites and canine aggression in 21 dominant-aggressive dogs (Canis familiaris) and 19 controls. The diagnosis of dominance-related aggression was based upon a history of biting family members in contexts associated with dominance challenges. Post-mortem CSF 5-HIAA, MHPG and HVA were measured by high-performance liquid chromatography using electrochemical detection. Concentrations of CSF 5-HIAA (P = 0.01) and HVA (P < 0.001) were lower in the aggressive group (median values: 5-HIAA 202.0 pmol/ml; HVA 318.0 pmol/ml) than in controls (5-HIAA 298.0 pmol/ml; HVA 552.0 pmol/ml). No differences were noted in CSF MHPG levels. Differences in 5-HIAA were maintained after controlling for breed and age of dogs, but HVA differences may have been breed-dependent. Lower levels of 5-HIAA (P = 0.02) and HVA (P = 0.04) were found in the subgroup of aggressive dogs with a history of biting without warning (5-HIAA 196.0 pmol/ml; HVA 302.0 pmol/ml) compared to dogs that warned (5-HIAA 244.0 pmol/ml; HVA 400.0 pmol/ml). This study suggests that reduced serotonergic function is associated with aggressive behavior and impaired impulse control in dogs, a finding that is consistent with observations in primates, and suggests that serotonin modulates aggressive behavior throughout mammals.
As noted previously, it is likely that the tendency to lash out verbally or physically at others is influenced by an interaction among multiple complex biologic factors. We need to investigate how these systems interact with each other to develop a more thorough understanding of the brain's influence over aggressive behavior. We are at a very early stage in our understanding of the neurobiology of aggression. There are no simple tools for studying the complex neurophysiology of the human brain. The studies cited in this article include techniques limited in their utility. As our technologies improve, discovering a more thorough picture of the brain's influence over aggressive behavior may be possible. For example, functional neuroimaging may help to localize abnormal neurotransmitter functioning in the brains of individuals with impulsive aggressive behavior. Our technologies are beginning to reveal the differential effects of subsystems of neurotransmitter regulation. Subtypes of serotonin receptors may differentially mediate impulsive aggressive behaviors. Animal studies suggest that 5-HT 1A receptor stimulation results in a decrease in aggressive behavior. As noted previously, aggressive personality-disordered patients show a blunted prolactin response to the 5-HT1A agonist buspirone. Antagonism of 5-HT 2 receptors appears to decrease aggression, and this effect may explain the ability of newer antipsychotic agents (which, unlike older antipsychotic medications, block 5-HT 2 receptors) to produce a dramatic reduction in aggression and agitation independent of effects on psychotic symptoms. Neglecting psychosocial factors in the causes of aggressive behavior would also be naive. Although environmental factors account for much of the predisposition to aggression, there have been few systematic studies to explore the relationship between life experiences and aggression. In addition, there have been no well-designed studies of the interaction between biology and an individual's environment in the genesis of aggressive behavior. There is some evidence of an association between childhood abuse and neglect and adult antisocial personality disorder, but this relationship might be merely an artifact of the genetic relationship between parental and offspring antisocial personality disorder. As we discussed in the introduction, one of the biggest hurdles in the study of the neurobiology of aggression is the lack of a consensus on definitions. "Intermittent Explosive Disorder" is the only category in DSM-IV that directly addresses individuals with problems with aggression, but the criteria are vague and only focus on a handful of the many patients who exhibit problems with aggressive behavior. It is our hope that investigators in this field can work together toward developing more precise and encompassing diagnostic criteria to study effectively both the neurobiology and treatment of these disorders.
The agouti locus influences coat color by antagonizing melanocyte-stimulating hormone (MSH) at its receptor on pigment cells and may antagonize MSH in neural tissue. This study replicates work on rats to assess whether behavioral (neural) effects of the agouti locus are as similar across mammals as those on coat color. Handling, open-field, platform jump, and food-novelty tests were conducted on agouti and nonagouti deer mice (Peromyscus maniculatus) following protocols in C. A. Cottle and E. O. Price (1987). As with rats, nonagouti deer mice were less aggressive, less active, and easier to handle compared with their agouti counterparts. Nonagouti deer mice also groomed more than agouti subjects. Thus, behavioral effects of the agouti locus are conservative, and agouti may be an important modulator of melanocortins in neural as well as integumentary tissue.
The questionnaire survey of Hart and Hart (1985,Journal of the American Veterinary Medical Association186, 1811–1815) ranked the 56 most popular breeds of dog in theon 13 behavioural traits and is compared here with results of a similar survey conducted on the 49 most popular breeds in the. Of the 36 breeds in common between the studies, 24 were similar for the traits aggressivity, reactivity and ease of housetraining between the two countries. However, the characteristics of nine breeds (Airedale Terrier, Old English Sheepdog, Welsh Corgi, Irish Setter, Standard Poodle, Beagle, Samoyed, Boxer, Dalmatian) differed markedly between the two countries, and a further three (Chihuahua, Scottish Terrier, Standard
Dachshund) showed smaller, but probably meaningful, shifts. These differences should be recognised when giving advice to prospective owners, and when treating unwanted behaviour in these breeds.
In humans and other primates low cerebrospinal fluid (CSF) levels of the major serotonin (5-HT) metabolite 5-hydroxyindoleacetic acid (5-HIAA) have been correlated to high aggressiveness. This finding forms the basis of the 5-HT deficiency hypothesis of aggression. Surprisingly, this correlation has not been confirmed in rodents so far, while manipulation studies aimed to investigate the link between 5-HT and aggressive behaviour are mostly carried out in rodents. In this study the relation between aggression and CSF monoamine and metabolite concentrations was investigated in male Wildtype Groningen rats. In sharp contrast to the hypothesis and our expectation, a clear positive correlation was found between the individual level of trait-like aggressiveness and CSF concentrations of 5-HT, 5-HIAA, norepinephrine (NE), dopamine (DA), and 3,4-dihydroxyphenylacetic acid (DOPAC). Shortly after the acute display of aggressive behaviour (as a state-like phenomenon), decreased 5-HT levels and an increase in 5-HIAA/5-HT ratio and NE concentrations were found. Surprisingly, pharmacological challenges known to influence 5-HT transmission and aggressive behaviour did not affect CSF 5-HT and 5-HIAA concentrations, only the NE level was increased. Lesioning 5-HT terminals by 5,7-dihydroxytryptamine (5,7-DHT) administration caused a decrease in CSF 5-HT and 5-HIAA, but without affecting aggressive behaviour. The observed positive correlation between CSF 5-HIAA and trait aggressiveness makes it questionable whether a direct extrapolation of neurobiological mechanisms of aggression between species is justified. Interpretation of CSF metabolite levels in terms of activity of neural substrates requires a far more detailed knowledge of the dynamics and kinetics of a neurotransmitter after its release.