Behavioral profiles of dog breeds

Breed behavior profiles were obtained by a method that was quantitative and free of personal biases. The profiles concerned 13 traits, eg, excitability, snapping at children, watchdog barking, and affection demand, which are of interest to people wanting dogs as pets. Authorities for the development of the profiles were 48 small animal veterinarians and 48 obedience judges, randomly selected from directories so as to represent equally men and women, and eastern, central, and western geographic regions of the United States. Each authority was asked to rank on each of the behavioral traits a list of 7 breeds chosen randomly from a list of 56 breeds. The data were analyzed in a custom-designed computer program that pooled the data and then ranked all 56 breeds on the basis of the 13 traits. The results indicated that some behavioral traits discriminate between breeds better than others. An examination of sample profiles indicated the feasibility of developing a statistically meaningful behavioral profile that integrates comparative rankings of several authorities balanced as to representation of geographic location, sex, and type of experience with dogs.     

Selecting pet dogs on the basis of cluster analysis of breed behavior profiles and gender

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.     

Comparison of behavioral characteristics of dogs in the United States and Japan

This study examined the difference in dog owning between Japan and the United States, and the effect of these differences on dogs’ behavioral characteristics. Behavioral evaluations of privately-owned dogs were obtained by using online questionnaire. We compared background and demographic information from the two countries and analyzed the effects of these differences on behavioral characteristics in dogs. The results indicated that there was a bias in the dog breeds kept in Japan compared to the United States and that Japanese dogs’ body weight was lower than the US dogs. The main source of dog acquisition was pet stores in Japan and breeders and/or shelters in the United States. Multiple linear regression analysis found that Japanese dogs showed more aggression to household members and higher energy, restlessness and fear of non-social stimuli than US dogs, while US dogs showed more fear of unfamiliar persons, separation-related behavior and excitability. US dogs also showed higher levels of trainability and attachment to owners. The lower dog’s body weight was, the higher the behavioral scores except for trainability were. When dogs that were obtained under 3 months of age were analyzed, the younger the dogs were when their owners obtained them, the higher the scores on some behavioral problem factors were. The higher rates of problem behaviors among Japanese dogs compared with US dogs suggest that the preference for small breed dogs and poor early development environment influenced the behavioral characteristics of dogs.     

Owner complaints of canine behavior in Iran–A preliminary survey

The current survey assessed 17 common behavioral complaints reported by 234 dog owners attending the Small Animal Hospital, University of Tehran using a questionnaire. According to the results, nearly 95% of dog owners reported at least 1 undesirable behavior in their dogs. Aggression toward other dogs and people, jumping up, and excessive barking were the most common behavioral complaints. Owners of large-breed dogs were more likely to complain about their dogs’ aggressive behaviors toward people/dogs and excessive barking compared with owners of small-breed dogs. Dogs without access to a yard were more likely to show phobia-associated behaviors, fearfulness, and separation-related behaviors, whereas those having access to a yard were more likely to show aggressive behaviors toward people/dogs and excessive barking. Interaction of dogs with people and type of reaction used by owners in response to the behavior were also related with some other behavioral characteristics of the animals.     

Demographic characteristics of dog population in Switzerland

Dog Registration data from three Cantons, patient data of 13 veterinary practices and registrations in the Swiss Dog Pedigree Book were collected, analysed and compared to results of a commercial household survey, to assess demographic characteristics of dog population in Switzerland. The proportion of "pure-bred" dogs was different depending on how the term was used, varying from 24% regarding registrations in the Swiss Dog Pedigree Book, to 75% regarding dogs with only one breed recorded in Veterinarian's patient-history-management systems. Most popular breeds were dogs called "German Shepherd/Shepherd", followed by the Labrador and Golden Retriever. Comparison of different data sources suggested regional differences in popularity of breeds. The average life expectancy was estimated on 10.5 and 11 years. Sex distribution was equal. One third of all male dogs and half of the female dogs were neutered. Regardless sex, neutering was more common in cross-bred dogs than in "pure-bred" dogs (OR = 1.9). Some bias in all sources had to be considered and there was a major concern regarding definition of breeds. However, the study was able to add different parameters out of different sources to a homogenous picture of demographic data of dog population in Switzerland.     

Behavioral characteristics of English Cocker Spaniels with owner-defined aggressive behavior

Information on the behavior of both aggressive and nonaggressive (control) English cocker spaniels (ECS) recruited for genetic analysis is presented. Information from a total of 122 dogs was gathered using questionnaires and owner interviews, resulting in analysis of 52 aggressive (5 aggressive dogs were excluded from the analysis) and 65 control dogs. Owners rated their dogs with 5-point frequency scales for unacceptable behavior toward humans (17 items), fear (20 items), barking (8 items), and aggression toward other dogs (4 items). The results show that serious, repeated growling is the most pronounced single behavior characterizing the aggressive ECS, and this seems to be the most important behavior causing owners to classify their dogs as aggressive. The other main behavior characteristic of the aggressive group was skin-penetrating bites. Snapping and “biting in general” were also frequently reported among these dogs. The objective of this study was to describe some behavioral characteristics of ECS showing owner-defined aggressive behavior, and behavioral differences between these dogs and a group of ECS with excellent behavior.     

Breed, age and gender distribution of dogs with chronic hepatitis in the United Kingdom

Standardised histological criteria are now available for the diagnosis of canine chronic hepatitis (CH). CH is common in dogs, but no studies have reported breed, age and gender distributions in the United Kingdom (UK). The objective of this study was to determine which breeds had an increased risk for developing CH in the UK and to report the age and gender distribution for those breeds. The databases of six veterinary histopathology laboratories were searched for cases with a histological diagnosis of CH according to standardised criteria. The breed, age and gender of dogs was recorded and compared to a control population to calculate the odds ratio and 95% confidence intervals for developing CH. A total of 551 cases of CH were identified, consisting of 61 breeds. Nineteen breeds were represented by five or more cases. Breeds with an increased risk for developing CH included the American cocker spaniel, Cairn terrier, Dalmatian, Dobermann pinscher, English cocker spaniel, English springer spaniel, Great Dane, Labrador retriever and Samoyed. The median age at diagnosis for all breeds with CH was 8 years (range 7 months to 16 years). Dalmatians, Dobermann pinschers and English springer spaniels with CH were significantly younger than Cairn terriers, English cocker spaniels and Labrador retrievers with CH. Females were over-represented when all cases were examined together. In conclusion, several breeds in the UK have an increased risk of CH, some of which have not been previously reported.     

Genetic polymorphism as a background of animal behavior

Various studies have shown the associations between differences in human behavioral traits and genetic polymorphism of neurotransmitter-related proteins such as receptors, transporters and monoamine oxidase. To clarify the genetic background of animal behavior, corresponding regions in animals have been analyzed. The study has been especially focused on primates, as the evolutionally closest animal to humans, and on dogs, as the socially closest animal to humans. In primates, polymorphisms were discovered between or within species, and the functional effects on neural transmission were found to be different by alleles. Even in apes, the closest species to humans, function was different from that in humans. In dogs, allele distributions of several genes were different among breeds showing different behavioral traits, and genes associated with individual differences in aggressiveness and aptitude of working dogs were surveyed. The survey of behavior-related genes has also been carried out in other mammals such as horses and cetaceans. Genes controlling various behaviors in birds have also been reported. The marker genes for behavior will provide useful information for human evolution, welfare of zoo animals and effective selection of working dogs and industry animals.     

Assessment of the factorial structures of the C-BARQ in Japan

In order to introduce the Canine Behavioral Assessment and Research Questionnaire (C-BARQ), which is a standardized system for evaluating the behavioral traits of dogs, to Japan, where the environment with respect to dog ownership is thought to differ from those of the United States and Europe, we compared demographic information on dogs in the United States and Japan and examined whether similar factors could be extracted from both countries using questionnaire items of the C-BARQ. The C-BARQ was completed by 11,410, and 734 dog owners respectively in the United States and Japan, and some demographic differences were found, such as breed and neuter status. Data from completed questionnaires were subjected to factor analysis, and the resulting factors were tested for reliability. In the United States, factor analysis yielded 11 factors from 63 items that accounted for 52.9% of the common variance. In Japan, 15 factors were extracted, and these accounted for 57.0% of the common variance. The present factors for the United States were almost identical to the factors identified in a previous study, and similar factors were extracted in both countries. Therefore, the C-BARQ can function effectively as a fundamental behavioral evaluation system for dogs in Japan.     

Prevalence of Giardia in symptomatic dogs and cats throughout the United States as determined by the IDEXX SNAP Giardia test

National prevalence of Giardia infection in dogs and cats presenting to clinics with vomiting and/or diarrhea was examined using the IDEXX SNAP Giardia test kit. Veterinary practices across the United States were sent an invitation to participate in the survey and asked to use the test on fecal samples from the target population. The survey requested that the clinics report the results of 20 or more tests. A total of 21,092 results were reported, comprised of 16,114 dogs and 4,978 cats. Analysis of the data (excluding the handful of results reported from Puerto Rico) showed a Giardia prevalence of 15.6% among dogs tested, and 10.8% among cats. This difference was statistically significant (p < 0.001). Regional categorization into Northeast, Southeast, West, and Midwest drew out significant (p < 0.001) differences in prevalence in most cases for dogs; the differences were not significant for cats. These differences and other variables are currently being examined with this and additional data sets. We conclude on the basis of the SNAP test diagnostic that Giardia is a common enteric agent among dogs and cats with gastrointestinal signs.     

Babesia gibsoni infection among dogs in the southeastern United States

OBJECTIVE: To identify subclinical Babesia gibsoni infection in American Pit Bull Terriers from the southeastern United States and to determine the genetic sequence of parasite DNA isolated from these dogs. DESIGN: Case series. ANIMALS: 33 American Pit Bull Terriers and 87 dogs of various other breeds. PROCEDURE: Blood smears were examined for microscopic evidence of the parasite, and DNA was extracted from blood samples and used in a polymerase chain reaction (PCR) assay designed to amplify the small subunit ribosomal RNA gene sequence of B. gibsoni. Amplification products of the expected size were sequenced, and sequences were compared with published sequences for B. gibsoni isolates. Hematocrit, platelet count, mean platelet volume, WBC count, and eosinophil count were compared between dogs with positive PCR assay results and dogs with negative results. RESULTS: Results of the PCR assay were positive for 18 of the 33 (55%) American Pit Bull Terriers, including all 10 dogs with microscopic evidence of parasitemia. Only 1 of these dogs was clinically ill at the time blood samples were collected. Results of microscopic evaluation of blood smears and of the PCR assay were negative for the 87 other dogs. Hematocrit and platelet count were significantly lower in dogs with positive PCR assay results than in dogs with negative results. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that American Pit Bull Terriers in the southeastern United States may be subclinically infected with B. gibsoni. However, subclinical infection was not identified in dogs of other breeds from the same geographic area.     

Dogs Entering the United States from Rabies‐Endemic Countries, 2011–2012

International dog imports pose a risk because of the potential movement of disease agents, including the canine rabies virus variant which has been eliminated from the United States since 2007. US regulations require a rabies vaccination certificate for dogs arriving from rabies‐endemic countries, but permit the importation of dogs that have not been adequately immunized against rabies, provided that the dogs are confined under conditions that restrict their contact with humans and other animals until they have been immunized. CDC Form 75.37, ‘Notice to Owners and Importers of Dogs’, explains the confinement requirements and serves as a binding confinement agreement with the importer. In this evaluation, we describe the characteristics of unimmunized dogs imported into the United States over a 1‐year period based upon dog confinement agreements recorded at the Centers for Disease Control and Prevention (CDC) quarantine stations. Confinement agreements were issued for nearly 2800 unimmunized dogs that entered the United States during 1 June 2011–31 May 2012, the majority of which travelled to the United States by air and without any seasonal pattern in import volume. Over 60% of these animals were puppies <3 months of age and included a wide variety of breeds. The dogs arrived from 81 countries, with the majority arriving from North America or Europe. Dogs placed on confinement agreements had final destinations in 49 states. California, New York, Texas, Washington and Florida received the largest number of dogs on confinement agreements. These results (which do not reflect human travel or US dog ownership data) suggest that a large portion of unimmunized dogs arrive from rabies‐endemic countries for commercial, shelter and rescue purposes. Further evaluation and key stakeholder involvement are needed to assess whether the current dog importation regulations are an adequate compromise between the benefits and risks of dog importation.     

Allele frequency distribution of the canine dopamine receptor D4 gene exon III and I in 23 breeds

Various canine breeds are remarkably different from each other not only in their sizes and shapes but also in behavioral traits, suggesting that some of them are under genetic control. Although dopaminergic neurotransmission system is considered to affect animal behavior, little is known about related genes in canine. Relations between specific alleles in polymorphic regions of the dopamine receptor D4 gene (DRD4) and personality or psychiatric disorders have been reported in humans, and we first found polymorphism in exon III region of the gene in 4 canine breeds. In this study we surveyed allele frequency distribution in 23 breeds including a total of 1,535 unrelated individuals. In exon III, 8 alleles including a novel allele were identified. A group of breeds in which the alleles 447b, 498 and 549 were frequent tended toward high scores in aggression-related behavioral traits than that with frequent alleles 435 and 447a. Moreover, a polymorphism based on 24 bp insertion/deletion was found in exon I region for the first time in dogs. This information may be of use for candidate gene studies of behavioral variation in dogs.     

Polymorphisms in the canine glutamate transporter-1 gene: identification and variation among five dog breeds

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.     

Update of a Retrospective Cohort Study of Changes in Hip Joint Phenotype of Dogs Evaluated by the OFA in the United States, 1989–2003

Objective— To determine whether there has been improvement in canine hip joint phenotype classifications of dogs whelped from 1989 to 2003 by the Orthopedic Foundation for Animals (OFA), by examining results of radiographic evaluations and identifying any trends in percentages of dogs classified as having desirable hip joint phenotypes.
Study Design— Retrospective cohort study.
Sample Population— OFA radiographic classifications (n=431,483) on dogs whelped between 1989 and 2003.
Methods— Numbers and percentages of dogs classified by hip joint phenotypes were determined for 2-year cohorts. Differences between breeds and sexes were assessed using the Fisher's exact test, and odds ratios with 95% confidence intervals were calculated to express associations. The Cochran–Armitage test for trend was calculated to identify significant trends over time.
Results— There were statistically significant ( P <.05) increases in the proportion of all breeds of dogs evaluated as excellent and good from 1993 to 2003, controlling for gender and age at evaluation. Labrador Retrievers, Bernese Mountain Dogs, and Rottweilers had the highest proportions of excellent and good scores, and the highest rates of improvement in excellent and good scores were seen in Bernese Mountain Dogs and Rottweilers.
Conclusions— Results support the contention that there have been improvements in hip joint phenotype classifications in dogs in the United States since the previous study (1989–1992), through increases in the proportion of dogs receiving excellent and good classifications.
Clinical Relevance— Hip joint phenotype classifications can be used by dog breeders to develop breeding programs to improve the hip joints of future generations of dogs.     

Clinical effectiveness and safety of a new NSAID, firocoxib: a 1,000 dog study

For the Previcox (firocoxib, Merial) Experience Trial, practicing veterinarians across the United States were asked to enroll dogs diagnosed with osteoarthritis (OA). At an initial visit, owners of dogs deemed suitable for NSAID therapy were given Previcox and instructed to maintain a daily diary and to return 10 and 40 days after treatment began. Approximately 86% of the 1,002 enrolled dogs completed the study. The withdrawal rate associated with gastrointestinal side effects was low (2.9% of dogs), and no serious drug-related adverse events were reported. Investigators and Owners rated 93% and 91% of dogs, respectively, as improved, and 86% of owners rated their dogs "happier" or "more active" after treatment with firocoxib. The improvements observed following initiation of firocoxib therapy were independent of gender, breed, starting body weight, age, and prior NSAID use. These results support previous findings indicating that firocoxib is well tolerated and effective when used under field conditions.     

Distraction index as a risk factor for osteoarthritis associated with hip dysplasia in four large dog breeds*

Objective : To determine if age, breed, gender, weight or distraction index (DI) influenced the risk of radiographic osteoarthritis (OA) of canine hip dysplasia (CHD) in four common dog breeds; the American bulldog, Bernese mountain dog, Newfoundland and standard poodle. Materials and Methods : This was a cross sectional prevalence study with 4349 dogs. Canine hips were evaluated using 3 radiographic projections: the hip-extended view, the compression view and the distraction view. The hip-extended view was examined for the presence of OA. The PennHIP distraction view was utilized to calculate the DI. For all breeds, a multiple logistic regression model incorporating age, weight, gender, and DI was created. For each breed, disease-susceptibility curves grouping dogs on the basis of age were constructed. Receiver-operating characteristic (ROC) curves were developed for each breed regardless of age. Results : For all breeds, DI was the most significant risk factor for the development of OA associated with CHD. Weight and age were also significant risk factors in all four breeds, but gender was not. Clinical Significance : Results from this study support previous findings, that irrespective of breed, the probability of radiographic OA increases with hip joint laxity as measured by the DI. Breed-specific differences in this relationship, however, warrant investigation of all breeds affected by CHD to determine inherent dependency of hip OA on joint laxity. Such findings guide veterinarians in helping dog breeders to make evidence-based breeding decisions and in informing dog owners to implement preventative treatments for CHD for dogs found to be at risk.     

Breeds of dogs involved in fatal human attacks in the United States between 1979 and 1998

OBJECTIVE: To summarize breeds of dogs involved in fatal human attacks during a 20-year period and to assess policy implications. ANIMALS: Dogs for which breed was reported involved in attacks on humans between 1979 and 1998 that resulted in human dog bite-related fatalities (DBRF). PROCEDURE: Data for human DBRF identified previously for the period of 1979 through 1996 were combined with human DBRF newly identified for 1997 and 1998. Human DBRF were identified by searching news accounts and by use of The Humane Society of the United States' registry databank. RESULTS: During 1997 and 1998, at least 27 people died of dog bite attacks (18 in 1997 and 9 in 1998). At least 25 breeds of dogs have been involved in 238 human DBRF during the past 20 years. Pit bull-type dogs and Rottweilers were involved in more than half of these deaths. Of 227 reports with relevant data, 55 (24%) human deaths involved unrestrained dogs off their owners' property, 133 (58%) involved unrestrained dogs on their owners' property, 38 (17%) involved restrained dogs on their owners' property, and 1 (< 1%) involved a restrained dog off its owner's property. CONCLUSIONS: Although fatal attacks on humans appear to be a breed-specific problem (pit bull-type dogs and Rottweilers), other breeds may bite and cause fatalities at higher rates. Because of difficulties inherent in determining a dog's breed with certainty, enforcement of breed-specific ordinances raises constitutional and practical issues. Fatal attacks represent a small proportion of dog bite injuries to humans and, therefore, should not be the primary factor driving public policy concerning dangerous dogs. Many practical alternatives to breed-specific ordinances exist and hold promise for prevention of dog bites.     

Prevalence of the breed-related glaucomas in pure-bred dogs in North America

Objective To determine the prevalence of the breed‐related glaucomas in pure‐bred dogs presented to the veterinary medical teaching hospitals in North America that participate in the Veterinary Medical Data Base (VMDB). Materials and methods In this retrospective study, age of first diagnosis, breed, and gender data for all breeds of dogs were collected from the VMDB with the clinical diagnosis of primary glaucoma (glaucoma‐NOS) at 5–10 year intervals from 1964 to 2002. The prevalence for each breed (affected dogs compared to all dogs of each breed), any changes over the 38 years, and any gender differences for these glaucomas were determined. Results The prevalence of the primary breed‐related glaucomas has gradually increased from 0.29% (1964–1973); 0.46% (1974–1983); 0.76% (1984–1993); to 0.89% (1994–2002). Breeds that consistently featured among the highest 10 for glaucoma prevalence from four different periods (1964 to 2002) included American Cocker Spaniel, Basset Hound, Wire Fox Terrier, and Boston Terrier. During the last observation period (1994–2002), 22 different breeds had 1% or higher prevalence of the glaucomas. The highest prevalence of glaucomas in 1994–2002 by breed included: American Cocker Spaniel (5.52%); Basset Hound (5.44%); Chow Chow (4.70%); Shar‐Pei (4.40%); Boston Terrier (2.88%); Wire Fox Terrier (2.28%); Norwegian ElkHound (1.98%); Siberian Husky (1.88%); Cairn Terrier (1.82%); and Miniature Poodle (1.68%). A predominance of females with glaucoma occurred in the American Cocker Spaniel, Basset Hound, Cairn Terrier, Chow Chow, English Cocker Spaniel, Samoyed, and perhaps the Siberian Husky, and a predominance of males in the Australian Cattle dog and St Bernard. Age affected the time for first presentation of the glaucomas in the pure‐bred dog. In the majority of breeds the glaucomas were presented for initial diagnosis in dogs between 4 and 10 years of age. Conclusion Breed‐related glaucomas in pure‐bred dogs are frequently presented to the veterinary medical teaching hospitals in North America. The prevalence of the breed‐related glaucomas in the dog appears similar to humans, and in some breeds exceeds that in humans. In many breeds the high prevalence of the glaucomas suggests a genetic basis.     

Sequences of canine glutamate decarboxylase (GAD) 1 and GAD2 genes, and variation of their genetic polymorphisms among five dog breeds

Glutamate decarboxylase (GAD) is the primary enzyme in the brain that catalyzes the synthesis of gamma-aminobutyric acid (GABA), the main inhibitory neurotransmitter. There are two isoforms named according to their molecular weights, GAD67 and GAD65, which are encoded by GAD1 and GAD2, respectively. To investigate the association between GAD genes and temperament in domestic dogs, Canis familiaris, we sequenced the full lengths of the coding regions of these genes and identified three single nucleotide polymorphisms (SNPs) in GAD1 and one in GAD2. When comparing genotype and allele frequencies of SNPs among five breeds with different behavioral traits, statistically significant interbreed differences were observed for three SNPs in GAD1. These results suggest that GAD1 SNPs may be useful for behavioral genetic studies in dogs.