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Inherited defects in pedigree dogs. Part 1: Disorders related to breed standards
Abstract
The United Kingdom pedigree-dog industry has faced criticism because certain aspects of dog conformation stipulated in the UK Kennel Club breed standards have a detrimental impact on dog welfare. A review of conformation-related disorders was carried out in the top 50 UK Kennel Club registered breeds using systematic searches of existing information. A novel index to score severity of disorders along a single scale was also developed and used to conduct statistical analyses to determine the factors affecting reported breed predisposition to defects. According to the literature searched, each of the top 50 breeds was found to have at least one aspect of its conformation predisposing it to a disorder; and 84 disorders were either directly or indirectly associated with conformation. The Miniature poodle, Bulldog, Pug and Basset hound had most associations with conformation-related disorders. Further research on prevalence and severity is required to assess the impact of different disorders on the welfare of affected breeds.
... In many cases, desirable aesthetic features are the product of inbreeding and positive selection for increasingly extreme physical traits, without regard for associated health issues. There is much evidence to showcase inbreeding to achieve pedigree breed standard's association with hereditary pathology and conformational disorders [3,4], including orthopaedic and joint disorders [3,5,6]; skin disease [3,7]; aural disease [3,8,9]; ocular disease [4,10]; and breathing difficulties, such as those resulting from Brachycephalic Obstructive Airway Syndrome (BOAS) [4,[11][12][13]]. Holland's 2019 review of factors contributing to dog acquisition behaviour concluded that identifying underlying breed trends could enable stakeholders to respond to consumer behaviour more appropriately [14]. ...
... In many cases, desirable aesthetic features are the product of inbreeding and positive selection for increasingly extreme physical traits, without regard for associated health issues. There is much evidence to showcase inbreeding to achieve pedigree breed standard's association with hereditary pathology and conformational disorders [3,4], including orthopaedic and joint disorders [3,5,6]; skin disease [3,7]; aural disease [3,8,9]; ocular disease [4,10]; and breathing difficulties, such as those resulting from Brachycephalic Obstructive Airway Syndrome (BOAS) [4,[11][12][13]]. Holland's 2019 review of factors contributing to dog acquisition behaviour concluded that identifying underlying breed trends could enable stakeholders to respond to consumer behaviour more appropriately [14]. ...
... In many cases, desirable aesthetic features are the product of inbreeding and positive selection for increasingly extreme physical traits, without regard for associated health issues. There is much evidence to showcase inbreeding to achieve pedigree breed standard's association with hereditary pathology and conformational disorders [3,4], including orthopaedic and joint disorders [3,5,6]; skin disease [3,7]; aural disease [3,8,9]; ocular disease [4,10]; and breathing difficulties, such as those resulting from Brachycephalic Obstructive Airway Syndrome (BOAS) [4,[11][12][13]]. Holland's 2019 review of factors contributing to dog acquisition behaviour concluded that identifying underlying breed trends could enable stakeholders to respond to consumer behaviour more appropriately [14]. ...
Simple Summary
Over the last ten years, the UK (United Kingdom) puppy trade has moved almost entirely online. Breed demand and impulse buying have made puppies lucrative commodities in an industry driven by profitability. To compensate, production levels have risen, feasibly fuelled by unethical breeding, poor husbandry/handling practice, and reduced overheads. As a result, breeding stock and puppies may have suffered potentially fatal physiological and long-term psychological issues. Surveys of veterinary professionals report an increase in sick puppies purchased online, whilst the British Small Animal Veterinary Association (BSAVA) reports an epidemic of canine inherited disease. The rapid growth of the puppy trade leaves significant gaps in regulation, and, to date, the nature of online trade remains difficult to quantify; however, a wealth of information can be gleaned from online advertisements, voluntarily posted to the public domain. This includes litter size, breed, seller location, activity, and more. In this study, a buoyant, consumer-driven market was revealed over a two-year period, in which the top 20 most advertised breeds were in accordance with the Kennel Club (KC) registered breed statistics, signifying a significant overlap with real-world data. Of all puppies advertised online, 66% were of 20 breeds, and 46.8% of puppies were listed as breeds linked to conformational disorders. Regional and seasonal fluctuations in price were evident, suggesting a market influenced by consumer trends. The highest number of advertisements per capita were located within Wales, the reported ‘puppy farm capital’ of the UK. Mean price for all breeds was GBP 927.14, increasing by over GBP 150 per individual, over the two-year duration of the study.
Abstract
The UK online puppy trade has rapidly outgrown the current legislation, aided by the anonymity provided by classified advertisement platforms. In an effort to meet increased demand, some unregulated and regulated breeders may have employed practices that negatively impact canine welfare. A paucity of up-to-date empirical data, necessary to characterise the scale and nature of this industry, makes intervention challenging. This study quantifies the online puppy trade via web-scraped online classified advertisements, providing empirical data that reveal market trends, along with spatial and temporal patterns. A total of 17,389 unique dog advertisements were collated and analysed over a 2-year period (1 June 2018 to 31 May 2020). The second year included the COVID-19 Lockdown (23 March 2020 to 31 May 2020). Statistical comparisons between dependent and independent variables were performed by linear regression. In the case of a single continuous variable, a one sample t-test was used. Of these advertisements, 57.2% were sourced from a pet-specific classified advertisement website (Pets4Homes, n = 9948), and the remaining 42.8% from two general classified advertisement websites (Gumtree, n = 7149, 41.1%; Preloved, n = 292, 1.7%, respectively). England exhibited the greatest number of advertisements (n = 10,493), followed by Wales (n = 1566), Scotland (n = 975), and Northern Ireland (NI; n = 344). Scaled for estimated human population density, Wales possessed as many advertisements per million inhabitants (489.4) as the other three combined (England = 186.4, Scotland = 177.3, and NI = 181.1). Across both years, 559 unique breeds were advertised, yet 66% of all advertisements focused on 20 breeds, and 48% advertisements focused on only 10 breeds. Regional breed popularity was suggested, with French Bulldog as the most advertised breed in England (7.3%), Scotland (6.8%), and Wales (6.8%), but Schnauzers were most popular within Northern Ireland (6.83%). Within the 559 unique breeds advertised, only 3.4% had links to conformational disorders CD); however, these breeds were among the most commonly advertised, totalling 46.9% of all ads. Across all regions, price density peaked between GBP 300 and GBP 1000, with Bulldogs presenting the greatest cost (mean = GBP 1461.38, SD = GBP 940.56), followed closely by French Bulldog (mean = GBP 1279.44, SD = GBP 664.76) and Cavapoo (mean = GBP 1064.56, SD = GBP 509.17). CD breeds were found to be GBP 208.07 more expensive, on average, than non-CD breeds. Our results represent a buoyant online market with regional and seasonal fluctuations in price, advertised breed frequency and total counts. This suggests a market influenced by consumer trends, with a particular focus on breed preference, despite links to illness/disease associated with conformation. Our findings highlight the value of utilising online classified advertisement data for long-term monitoring, in order to assist with evidence-based regulatory reform, impact measurement of targeted campaigns, and legislative enforcement.
... Brachycephalic dogs, with their flattened faces and shortened muzzles, have long been popular pets (Skipper 2021). But the unprecedented rise in ownership of breeds such as the Pug, Boston terrier and French bulldog in recent years has prompted numerous researchers and organisations to voice concerns about the health and welfare consequences of such facial morphologies (Asher et al. 2009;Rooney & Sargan 2009;Bateson 2016;Brachycephalic Working Group 2018;British Veterinary Association 2020a,b). Discourse has focused largely on a single, central conflict: between the clinical problems associated with extreme muzzle shortening (O'Neill et al. 2015(O'Neill et al. , 2017Packer et al. 2015a,b;Packer & Tivers 2015;Liu et al. 2017;Seppanen et al. 2019;Fawcett et al. 2019) and public demand for extremely brachycephalic breeds, not least because of their putatively appealing, cute appearance . ...
... It is widely agreed that breed-related brachycephalia in dogs is a serious animal welfare problem (e.g. see Asher et al. 2009;Rooney & Sargan 2009;Bateson 2016;Brachycephalic Working Group 2017British Veterinary Association 2020a,b;O'Neill et al. 2022), yet ownership of such breeds has increased dramatically across many countries in recent years (e.g. American Kennel Club 2020; Australian National Kennel Council 2020; The Kennel Club 2020). ...
... Others have found additional mutations to be associated with brachycephalic breeds, including in the gene BMP3, which has been shown to function in cranial development in a wide range of species (Schoenebeck et al. 2012), and a mutation in the DISH-EVELLED2 (DVL2) gene, apparently associated with vertebral and skull malformations in Bulldogs, French bulldogs and Boston terriers (Mansour et al. 2018;Niskanen et al. 2021). Reduced muzzle length is a breed-defining characteristic in most of these dogs, as can be seen from kennel club breed standards (Asher et al. 2009;Packer et al. 2015b), and it appears that the degree of muzzle shortening in these breeds has increased across the past 50 to 100 years (Young & Bannasch 2006; see also Knowler et al. 2019;Skipper 2021). But the relative contribution of all of these different genes to the coronal-plane 'kindchenschema' facial features are, as yet, unexplored. ...
Brachycephalic dog breeds are highly popular, yet their conformation-related disorders represent a major welfare concern. It has been suggested that the current popularity of such breeds can be explained by their cute, infant-like facial appearances. The concept of ‘kindchenschema’ refers to the observation that certain physical features of infant humans and other animals can automatically stimulate positive and nurturant feelings in adult observers. But the proposal that brachycephalic dogs possess heightened ‘kindchenschema’ facial features, even into adulthood, has never been formally investigated. Here, we hypothesised that relative muzzle shortening across a range of breeds would be associated with known ‘kindchenschema’ facial features, including a relatively larger forehead, larger eyes and smaller nose. Relative fronto-facial feature sizes in exemplar photographs of adult dogs from 42 popular breeds were measured and associated with existing data on the relative muzzle length and height-at-withers of the same breeds. Our results show that, in adulthood, shorter-muzzled breeds have relatively larger (taller) foreheads and relatively larger eyes (i.e. area of exposed eyeball relative to overall face area) than longer-muzzled breeds, and that this effect is independent of breed size. In sum, brachycephalic dog breeds do show exaggeration of some, but not all, known fronto-facial ‘kindchenschema’ features, and this may well contribute to their apparently cute appearance and to their current popularity as companion animals. We conclude that the challenge of addressing conformation-related disorders in companion dogs needs to take account of the cute, ‘kindchenschema’ looks that many owners are likely to be attracted to.
... In brachycephalic dogs, the base of the skull is shortened, which also includes a reduction in the length of the nasopharynx. This results in disturbances in the structure of the nasal turbinates, which often overgrow [56,57]. All congenital abnormalities, mainly related to the respiratory system, that affect brachycephalic dogs are jointly called the brachycephalic syndrome, which will be discussed later in this publication. ...
... Despite the growing popularity of these breeds worldwide [55,68,94], it has been shown that the morphological changes are relatively serious and are associated with hereditary head and neck disorders [55,56]. In brachycephalic dogs, the shortened base of the skull also includes a reduction in the length of the nasopharynx [57]. ...
... Therefore, in the brachycephalic breeds, the ethmoid turbinates may show a tendency to significantly overgrow into the nasopharynx due to the limited space in the already ossified nasal cavity [44]. The resulting contact between the mucosa-covered turbinates hinders the flow of air through the nose [56]. This is not a normal structure of the initial airway, and studies have shown that turbinate hypertrophy to the pharynx is a common condition in brachycephalic dogs [44]. ...
Dogs are a good starting point for the description and anatomical analysis of turbinates of the nose. This work aimed at summing up the state of knowledge on the shape of the nasal cavity and airflow in these domestic animals and dealt with the brachycephalic syndrome (BOAS) and anatomical changes in the initial airway area in dogs with a short and widened skull. As a result of artificial selection and breeding concepts, the dog population grew very quickly. Modern dog breeds are characterized by a great variety of their anatomical shape. Craniological changes also had a significant impact on the structure and physiology of the respiratory system in mammals. The shape of the nasal cavity is particularly distinctive in dogs. Numerous studies have established that dogs and their olfactory ability are of great importance in searching for lost people, detecting explosives or drugs as well as signaling disease in the human body. The manuscript describes the structure of the initial part of the respiratory system, including the nasal turbinates, and compares representatives of various animal species. It provides information on the anatomy of brachycephalic dogs and BOAS. The studies suggest that further characterization and studies of nasal turbinates and their hypertrophy are important.
... Artificial selection has led to the domestic dog, Canis lupis familiaris, becoming the most phenotypically distinct mammalian species on the planet [1,2]. However, distinctly differing health profiles have emerged across the spectrum of modern dog breeds that are closely aligned with common conformational features selected by humans such as brachycephaly [3][4][5]. Breeds such as Pugs, French Bulldogs and English Bulldogs with a brachycephalic (flat-faced) conformation have become phenomenally popular in the UK over recent decades [6][7][8][9]. However, there is growing concern from charity and welfare groups about serious health and welfare issues associated with these popular brachycephalic breeds [10,11] based on an expanding worldwide evidence base [5,12]. ...
... Predisposition to disorders associated with selection towards extremes of conformation in dog breeds have been reported since Charles Darwin theorised in 1868 that muscular defects in Scottish Deerhounds were related to their giant size [39]. Since then, a growing and large body of evidence has accumulated on breed predispositions related to conformation in dogs [3,4]. Conversely, the extent of the health differences between a breed and all remaining dogs could be taken as a measure of divergence of that breed from the mainstream of dogs [32]. ...
... Background Artificial selection has led to the domestic dog, Canis lupis familiaris, becoming the most phenotypically distinct mammalian species on the planet [1,2]. However, distinctly differing health profiles have emerged across the spectrum of modern dog breeds that are closely aligned with common conformational features selected by humans such as brachycephaly [3][4][5]. Breeds such as Pugs, French Bulldogs and English Bulldogs with a brachycephalic (flat-faced) conformation have become phenomenally popular in the UK over recent decades [6][7][8][9]. However, there is growing concern from charity and welfare groups about serious health and welfare issues associated with these popular brachycephalic breeds [10,11] based on an expanding worldwide evidence base [5,12]. ...
... Predisposition to disorders associated with selection towards extremes of conformation in dog breeds have been reported since Charles Darwin theorised in 1868 that muscular defects in Scottish Deerhounds were related to their giant size [39]. Since then, a growing and large body of evidence has accumulated on breed predispositions related to conformation in dogs [3,4]. Conversely, the extent of the health differences between a breed and all remaining dogs could be taken as a measure of divergence of that breed from the mainstream of dogs [32]. ...
Plain English summary
Pugs have become phenomenally popular in the UK over recent decades. The breed has a flat-faced look (brachycephalic) that many humans find highly attractive and ‘cute’ but this flat face is also linked to several serious health problems. Consequently, there is growing concern about the welfare issues associated with the popularity and health issues of Pugs. To get a better overall perspective on the health of Pugs, this study aimed to compare the risks of common disorders between Pugs and all remaining dogs.
The study collected clinical information from first opinion veterinary practices in the UK that were participating in VetCompass. Dogs were grouped as either Pugs or non-Pugs. Information was gathered from the clinical records on all disorders diagnosed in each group during 2016 and a list of the most common disorders in each group was generated.
From 905,544 dogs in the overall study, there were 16,218 (1.79%) Pugs and 889,326 (98.21%) non-Pugs. Pugs (2.36 years, interquartile range [IQR] 1.16–4.53) were generally younger than non-Pugs (4.44 years, IQR 1.90–8.12). Pugs (8.95 kg, IQR 7.80–10.17) were also generally lower in bodyweight than non-Pugs (14.07 kg, IQR 8.15–25.20). From a combined list of 40 common disorders among both groups of dogs, Pugs had increased risk for 23 (57.5%) but had reduced risk for 7 (17.5%) disorders compared to non-Pugs. The disorders with the highest relative risk in Pugs included brachycephalic obstructive airway syndrome (BOAS) (× 53.92 risk), narrowed nostrils (× 51.25), eye ulceration (× 13.01), and skin fold infection (× 10.98). Disorders with the lowest relative risk in Pugs included heart murmur (× 0.23), fatty lump (× 0.24), aggression (× 0.31), and wounds (× 0.53).
The study provides a broad evidence base on the positive and negative aspects of the health of Pugs. Disease predispositions were more common than disease protections, confirming the hypothesis that there are many critical health-related welfare challenges to overcome for Pugs. The widely differing health profiles between Pugs and other dogs in the UK suggest that the Pug has now diverged to such an extent from mainstream dog breeds that it can no longer be considered as a typical dog from a health perspective.
... Domestication and breed formation have unintentionally increased the number of deleterious genetic variants within breeds [14,15]. Individual breeds also have strong predispositions to specific inherited diseases [16][17][18][19]. The Online Mendelian Inheritance in Animals website Page 2 of 9 Bannasch et al. ...
... However, lifespan differs between breeds of the same weight class indicating that more than body size is a factor [31][32][33]. Morphological characteristics of dog breeds could be one factor, since it can have a critical effect on their lifespan and health [18,34]. Results for the effect of inbreeding on mortality have varied between previous studies [9,32]. ...
Background
Dog breeds are known for their distinctive body shape, size, coat color, head type and behaviors, features that are relatively similar across members of a breed. Unfortunately, dog breeds are also characterized by distinct predispositions to disease. We explored the relationships between inbreeding, morphology and health using genotype based inbreeding estimates, body weight and insurance data for morbidity.
Results
The average inbreeding based on genotype across 227 breeds was F adj = 0.249 (95% CI 0.235–0.263). There were significant differences in morbidity between breeds with low and high inbreeding (H = 16.49, P = 0.0004). There was also a significant difference in morbidity between brachycephalic breeds and non-brachycephalic breeds ( P = 0.0048) and between functionally distinct groups of breeds (H = 14.95 P < 0.0001). Morbidity was modeled using robust regression analysis and both body weight ( P < 0.0001) and inbreeding ( P = 0.013) were significant ( r 2 = 0.77). Smaller less inbred breeds were healthier than larger more inbred breeds.
Conclusions
In this study, body size and inbreeding along with deleterious morphologies contributed to increases in necessary health care in dogs.
... It has been assumed that often the main aim was breeding for curiosity, extravagance or cuteness which was achieved by overtyping of particular anatomic attributes [12]. Even if this statement may be regarded as too strong, many breed standards stipulated by kennel clubs have a detrimental impact on dog welfare because they foster certain aspects of conformation [13]. For instance, a literature analysis on breed standards of the top 50 breeds in the UK found that each breed has at least one aspect of its conformation predisposing it to a health disorder [13]. ...
... Even if this statement may be regarded as too strong, many breed standards stipulated by kennel clubs have a detrimental impact on dog welfare because they foster certain aspects of conformation [13]. For instance, a literature analysis on breed standards of the top 50 breeds in the UK found that each breed has at least one aspect of its conformation predisposing it to a health disorder [13]. ...
Objective Several dog breeds suffer from health and welfare problems due to unfavorable anatomies and high prevalence of inherited diseases. Veterinarians should care for animal health and welfare but they may also be involved in breeding management including the use of reproductive techniques.
Material and methods An online survey was conducted to find out how veterinarians who are involved in small animal reproduction regard ethical issues, which services they provide, how they discuss and handle ethical concerns and talk about them with breeders.
Results In total, 83 participants mainly from Europe completed the online survey. Opinions on which interventions are ethical or not were heterogeneous. Most respondents (79.2 %) found it ethical to perform artificial insemination (AI) in dogs which did not reproduce naturally before. However, 62.7 % of participants stated that surgical insemination is not ethical. Elective cesarean sections are considered not ethical by approximately half of the participants. A closer look at responses to the questions of whether AI is ethical under specific conse quences suggests that most veterinarians are making ethical and value judgments in terms of what is justifiable or not. However, more than 80 % feel at least sometimes compromised by ethical conflicts.
Clinical relevance This research intended to foster discussion of this topic. International strategies should be developed to support solving conflicts and dilemmas related to ethical issues in dog breeding and assisted reproduction, as well as diminishing physical disabilities and heritable diseases.
... Aging is a continuous, lifelong process that impacts health, behavior, and care requirements in humans and non-human animals. In the domestic dog, the diversity of physical conformation and breed-related features (such as body size) means that aging can impact dogs in varying ways, dramatically effecting longevity and morbidity (1)(2)(3)(4)(5). The impact of aging on behavior is also not straightforward (Figure 1), as age can have a linear relationship with certain behavioral traits [e.g., (6,9)] but a quadratic relationship with others [e.g., (7,10,11)] or exhibit a steep change in later life [e.g., (6,12)]. ...
... This is the case for the domestic dog, where larger breeds die at younger ages, due largely to an accelerated rate of growth between birth and adult size (17), which incurs growth-induced cellular damage via oxidative processes that reduce longevity (17)(18)(19). Large breeds can also be predisposed to a considerable number of inherited diseases related to their conformation, such as cardiovascular diseases, which contribute to their early mortality and morbidity (1) in addition to higher inbreeding coefficients, which are also associated with reduced longevity (5,20). ...
Behavioral development is a lifelong process where cognitive traits such as learning and memory may be expected to take quadratic or linear trajectories. It is common practice for operational purposes to reduce study subjects into chronological categories when conducting research. However, there are no agreed-upon thresholds for this practice, and the lack of standardization may hinder comparison between studies of normative and pathological aging. In this perspective review, chronological categories have been identified that can be considered to represent normative cognitive and neurological aging in domestic family dogs. These categories work to capture age-related developmental trajectories for the majority of dog breeds. It is encouraged that researchers studying cognition and behavior, pathological cognitive deficits, or welfare of dogs across age categories utilize the categories presented here to best enable comparison between studies. The proposed groups could also support education programs informing owners of what behavioral changes to expect in their dog as they age, but they cannot be used to reflect health-based needs associated with breed-specific morbidity. The use of the age categories proposed here highlights significant welfare issues for breeds with the shortest average lifespans (e.g., the Great Dane). Studies show no evidence of an increased rate of behavioral or cognitive aging in short-lived breeds, and the shortest-lived breeds are most likely to die when classified by the proposed categories as Mature Adults. Adoption of these chronological categories in future research would aid comparison between studies and identification of non-normative age-related pathologies.
... In parallel, the overuse of a small number of reproducers in closed populations has contributed to the random dissemination of inherited disorders and potential inbreeding depression effect on fitness traits (Leroy and Baumung 2011). It has been estimated that out of 396 inherited disorders identified in dogs, 84 were associated, directly or indirectly, with breed specific morphological features (Asher et al. 2009), while 312 were not (Summer et al. 2010), with variable incidence and consequence for dog health and welfare according to disease and breeds. ...
Since its domestication, the dog species has been shaped by man to fulfil a diversity of functional as well as social roles. In this review, we investigate how socio-cultural and technical development have influenced its differentiation into a numerous
number of more or less specialised morphotypes, and then, after the 19th century, into highly differentiated and homogenous breeds. Current dog breeding practices are characterised by features, which are more or less specific to the species and may have consequences on the health of dogs. Increasing concerns on welfare and health, combined with recent technological genomic and information breakthroughs are expected to affect the practices and governance of dog breeding, and drive the future evolution of dog breeds.
... Selection pressures towards exaggerated and extreme physical traits that are associated with high levels of conformation-related and hereditary pathology has led to major discussion and rethinking, especially over the past 15 years, around the ethics and welfare implications of breed as a concept for dogs [62,[70][71][72][73][74][75]. However, despite a large evidence base on serious health and welfare concerns, breeding towards extreme conformations as laid out in breed standards that were often arbitrarily drafted over a century ago continues to be implemented to gain a competitive advantage in dogs used for showing [24,76] or to meet ongoing consumer demand for quirky or unique physical attributes in dogs kept as companion animals (Sandøe et al. 2017). ...
Growing concerns over health and welfare impacts from extreme phenotypes in dogs have created an urgent need for reliable demographic information on the national breed structures of dogs.
This study included all dogs under primary veterinary care in the UK during 2019 at practices participating in VetCompass. Demographic data on these dogs were analysed to report on the frequency of common breeds and also to report on conformation, bodyweight, sex and neuter associations with these breeds.
The study included 2,237,105 dogs under UK veterinary care in 2019. Overall, 69.4% (n = 1,551,462) were classified as purebred, 6.7% (149,308) as designer-crossbred and 24.0% (536,335) as nondesigner-crossbred. Across 800 unique breed names, the most frequent breeds at any age were nondesigner-crossbred (n = 536,335, 24.0%), Labrador Retriever (154,222, 6.9%) and Jack Russell Terrier (101,294, 4.5%). Among 229,624 (10.3%) dogs aged under one year, the most frequent breeds were nondesigner-crossbred (n = 45,995, 20.0%), French Bulldog (16,036, 7.0%) and Cockapoo (14,321, 6.2%). Overall, based on breed characteristics, 17.6% (395,739) were classified as brachycephalic, 43.1% (969,403) as mesaticephalic and 8.3% (186,320) as dolichocephalic. Of 1,551,336 dogs that were classifiable based on breed, 52.6% (815,673) were chondrodystrophic. Of 1,462,925 dogs that were classifiable, there were 54.6% (n = 798,426) short haired, 32.6% (476,883) medium haired and 12.8% (186,934) long haired. Of 1,547,653 dogs that were classifiable for ear carriage, 24.5% (n = 379,581) were erect, 28.1% (434,273) were semi-erect, 19.7% (305,475) were v-shaped drop and 27.7% (428,324) were pendulous. Overall, there was a 1.09:1.00 ratio of male (n = 1,163,512; 52.2%) to female dogs (n = 1,067,552; 47.8%).
Health and welfare issues linked to popular breeds with extreme phenotypes suggest that there is much work to do to help owners to make more welfare-friendly decisions when choosing which type of dog to own.
... Dogs have been bred from relatively small founder populations, and they have been selected based on appearance, leading to high levels of inbreeding. Many breeds are also predisposed to inherited diseases [240][241][242][243] , but this can be less the case in some mixed breeds 244 . Evidently, the variation in allele frequency and differential predisposition to disease across dog populations makes them well-suited to uncover the genetic basis of diseases. ...
Alzheimer’s disease (AD) is characterized by brain plaques, tangles, and cognitive impairment. AD is one of the most common age-related dementias in humans. Progress in characterizing AD and other age-related disorders is hindered by a perceived dearth of animal models that naturally reproduce diseases observed in humans. Mice and nonhuman primates are model systems used to understand human diseases. Still, these model systems lack many of the biological characteristics of Alzheimer-like diseases (e.g., plaques, tangles) as they grow older. In contrast, companion animal models (cats and dogs) age in ways that resemble humans. Both companion animal models and humans show evidence of brain atrophy, plaques, and tangles, as well as cognitive decline with age. We embrace a One Health perspective, which recognizes that the health of humans is connected to those of animals, and we illustrate how such a perspective can work synergistically to enhance human and animal health. A comparative biology perspective is ideally suited to integrate insights across veterinary and human medical disciplines and solve long-standing problems in aging.
... The breed standards and breeding practices of many pedigreed dog breeds have been closely scrutinized in recent times. This scrutiny has revealed potential negative impacts of cosmetic procedures on dog health and welfare (for example, through tail-docking or ear-cropping, or alternatively breeding for tail-less) and negative impacts of breeding practices relating to desirable phenotypes on dog health and longevity [1]. Breeding for novel phenotypes excluded from the breed standard (for example rare coat color or variation in size e.g., giant or miniature) is more common in animals bred for purposes other than exhibition. ...
Background
Publicly available phenotype data and genotyping array data from two citizen science projects: “Doberman Health Surveys” and “The Doberman Diversity Project” were analyzed to explore relative homozygosity, diversity, and disorder risk according to geographical locale and breeding purpose in the Doberman.
Results
From the phenotypic data cohort, life expectancy of a Doberman at birth is 9.1 years. The leading causes of death were heart disease (accounting for 28% of deaths) and cancers (collectively accounting for 14% of deaths).
By genotyping, the world Doberman population exists as four major cohorts (European exhibition-bred, Americas exhibition-bred, European work, Americas pet/informal). Considering the entire Doberman population, four genomic regions longer than 500 Kb are fixed in 90% or more of 3,226 dogs included in this study. The four fixed regions reside on two autosomal chromosomes: CFA3:0.8–2.3 Mb (1.55 Mb); CFA3: 57.9–59.8 Mb (1.8 Mb); CFA31:0–1.2 Mb (1.2 Mb); and CFA31:4.80–6.47 Mb (1.67 Mb). Using public variant call files including variants for eight Doberman pinschers, we observed 30 potentially functional alternate variants that were evolutionarily diverged relative to the wider sequenced dog population within the four strongly homozygous chromosomal regions.
Effective population size (Ne) is a statistical measure of breed diversity at the time of sampling that approximates the number of unique individuals. The major identified sub-populations of Dobermans demonstrated Ne in the range 70–236. The mean level of inbreeding in the Doberman breed is 40% as calculated by the number of array variants in runs of homozygosity divided by the assayed genome size (excluding the X chromosome). The lowest observed level of inbreeding in the Dobermans assayed was 15% in animals that were first generation mixes of European and USA bred Dobermans. Array variant analysis shows that inter-crossing between European and USA-bred Dobermans has capacity to re-introduce variation at many loci that are strongly homozygous.
Conclusions
We conclude that efforts to improve breed diversity first should focus on regions with the highest fixation levels, but managers must ensure that mutation loads are not worsened by increasing the frequencies of rarer haplotypes in the identified regions. The analysis of global data identified regions of strong fixation that might impact known disorder risks in the breed. Plausible gene candidates for future analysis of the genetic basis of cardiac disease and cancer were identified in the analysis.
... One of the effects of inbreeding is the occurrence of genetic defects in the offspring. Some researchers have been developing genetic tests that can help exclude carriers of hereditary diseases from the breeding population (1,40). It is also important to implement regular health tests (and obtain certificates). ...
The aim of the study was to analyse the impact of inbreeding on the frequency of hereditary diseases and the number of genetically tested dogs. The pedigrees of 100 Chinese Crested dogs from Polish Kennel Club and information about genetic tests for hereditary eye diseases and other veterinary diagnoses were collected. Inbreeding coefficients and relatedness were estimated for all dogs examined. The relationship between the level of inbreeding and genetic testing was analysed with logistic regression. The relationship between the occurrence of eye disease carriers and sex or the level of inbreeding was also tested. A significant relationship (P < 0.01) was found between inbreeding and the number of animals genetically tested for PLL eye disease. The effect of sex or the level of inbreeding on the eye disease carrier status was non-significant (P > 0.05). However, in some inbred animals the status of the eye disease carrier could be connected with inbreeding, although this needs further research. We found that most of the dogs had related parents and genetic defects. We also found that the breeders often used related dogs, which reduced the genetic diversity of the group and caused hereditary diseases. We suggest that Chinese Crested dog breeders be more open about publishing DNA-test results, which is fundamental for the health of the breed.
... Thousands more are abused, neglected, or mistreated by their owners for a variety of reasons, from ignorance to wilful cruelty (Clancy and Rowan 2003;Arluke 2006). Due to inbreeding, line breeding, or selection for extremely high physical conformation requirements, several purebred dog breeds suffer from painful and crippling health issues (Asher et al. 2009;Summers et al. 2010). The demand for some pets is outpacing the supply, which has led to an increase in commercial pet "farming," while the trade in exotic pets kills and causes great suffering to wild animals during their capture, transport, and subsequent acquisition by owners who are unaware of proper husbandry and care (McClennan 2012). ...
A common word used to describe the types of social
attachments that frequently develop between humans and
their pets are "human-animal bond".
... Yet this breed-related brachycephalia has become widely recognized as an important constraint on dog health and welfare (Ekenstedt et al., 2020;Farrow et al., 2014;Hendricks, 1992;Liu et al., 2017;Njikam et al., 2009;O'Neill et al., 2015;O'Neill et al., 2017;O'Neill et al., 2019;Packer, Hendricks, Tivers & Burn, 2015;Packer et al., 2019;Roedler et al., 2013;Seppanen et al., 2019). Numerous professional bodies, charities, and pressure groups have highlighted breed-related brachycephalia as a serious animal welfare problem (Asher et al., 2009;Bateson, 2016;Brachycephalic Working Group, 2018;British Veterinary Association, 2020aRooney & Sargan, 2009). Yet, across a similar period, there has been an unprecedented increase in the ownership of several short-muzzled breeds and types (e.g., Teng et al., 2016). ...
Brachycephalic dog breeds have become increasingly popular in recent years, despite showing a high incidence of conformation-related disorders and early mortality. It has been suggested that this popularity might be explained by public perceptions of these short-muzzled dogs as looking particularly infant-like or “cute.” Here, the hypothesis that short-muzzled breeds are especially likely to be described as cute was investigated by analyzing the word contents of advertisements for dogs and puppies being sold online. The ages and breeds of dogs being advertised were considered, in addition to whether the text of each advertisement included the word “cute” or two associated words: “adorable” and “sweet.” Analyses of the entire sample of advertisements (n = 43,312) indicated that younger dogs were more likely to be advertised as “cute” and “adorable,” while older ones were more likely to be advertised as “sweet.” Short-muzzled, brachycephalic breeds (cranio-facial ratio < 0.5) were more likely to be advertised as “cute,” with brachycephalic puppies under 6 months of age being particularly likely to be called “cute” and also “adorable.” However, breed size had a larger and wider effect on word use in advertisements, with smaller dogs being advertised more frequently using all three words: “cute,” “adorable,” and “sweet.” When data for adult dogs only were considered (n = 11,400), and continuous muzzle shortening and age data were used, a somewhat different and more complex pattern of results were found. Use of the words “cute” and “adorable” were not associated with degree of muzzle shortening among these adult dogs, but “sweet” was used more often in advertisements for longer-muzzled breeds. We conclude that the present dataset provides partial support for the assertion that short-muzzled dogs are described as more “cute” than longer-muzzled ones, but that small size is a better predictor of the use of “cute” and its synonyms.
... Pain associated with chronic health conditions is also being increasingly recognised as an important contributor to a wide range of clinical behaviour problems in dogs and cats (Wiseman et al., 2001;Camps et al., 2012;Barcelos et al., 2015;Fagundes et al., 2018;Mills et al., 2020). In addition, inbreeding practices among dogs and cats are associated with an increased risk of a variety of potentially painful health conditions (Asher et al., 2009;Gunn-Moore et al., 2008;Summers et al., 2010;Bannasch et al., 2021). As such, understanding the link between painful health conditions and behaviour is an important topic for companion animal welfare. ...
Pain associated with chronic health conditions in non-human animals is an important animal welfare issue. To identify animals in pain and develop an understanding of the mechanisms by which pain affects behaviour, it is therefore important to establish the direct behavioural effects of painful health conditions. We reanalyse data from a cross-sectional survey that considered the presence or absence of a painful condition in dogs and quantified their affective predispositions using the Positive and Negative Activation Scale (PANAS). By applying ideas from network theory, we conceptualise pain as a stressor that exerts direct effects on a network of interacting behavioural variables, and subsequently estimated a network model of conditional dependence relations. Painful health conditions were positively conditionally associated with age (posterior mean partial correlation, ρ = 0.34; standard deviation [SD]=0.05), and negatively conditionally associated with the item 'your dog is full of energy' (ρ = -0.14; SD=0.06). In turn, the energy item was conditionally associated with other PANAS items which were marginally associated with pain, such as items representing ease of excitability and persistence in play. This suggests these marginal effects might be indirectly mediated via the energy item. Further, utilising the posterior predictive distribution we estimated that the median conditional probability (95% credible interval) of a painful health condition given an answer of 'strongly agree' on the energy item was 0.08 (0.05, 0.11), which increased to 0.32 (0.09, 0.58), given a response of 'strongly disagree'. This provides a potentially clinically useful interpretation of the conditional dependencies detected in the network.
... It is also important to consider that English bulldogs have a high prevalence for conformation-related disorders in general, including elbow dysplasia. 19,20 Although it is possible that English bulldogs may be predisposed to radial head OCD lesions, additional cases are required to substantiate this claim. ...
Objective:
To report a case of bilateral radial head osteochondritis dissecans (OCD) in a dog treated via lateral elbow arthroscopy portals.
Study design:
Case report.
Animals:
Six month old female spayed English bulldog.
Methods:
The dog was presented for a left thoracic limb lameness localized to the elbow. Computed tomography revealed bilaterally symmetrical mineralized fragments in the lateral compartment of the elbow joint and blunting of the medial coronoid processes. The fragments were associated with a thin donation bed along the caudolateral articular surface of the radial head with moderate surrounding subchondral bone sclerosis. Bilateral elbow arthroscopy was pursued. Arthroscopy was initiated via a standard medial approach, which allowed for abrasion arthroplasty of the radial incisure and medial coronoid process but provided insufficient access to the radial head lesions. A lateral arthroscopic approach was subsequently performed and provided excellent access to the radial head for fragment retrieval and abrasion arthroplasty.
Results:
Histopathology of the radial head fragments revealed mild cartilage degeneration and retention of cartilaginous cores within subchondral bone, consistent with OCD. Complete resolution of lameness and elbow pain were observed on clinical examination 5 months postoperatively.
Conclusion:
Radial head OCD can occur as a rare component of elbow dysplasia in growing dogs, and fragment retrieval with abrasion arthroplasty via lateral arthroscopic portals may be an effective treatment option.
... Domesticated dog breeds have undergone artificial selection, which has led to extreme phenotypic diversity between breeds as well as breed predispositions to many heritable disorders (Wayne and Ostrander 2007;Asher et al. 2009;Summers et al. 2010;Gough et al. 2018;Bannasch et al. 2021). In particular, many dog breeds are at a substantially higher risk for specific cancers compared with human populations (Schiffman and Breen 2015). ...
Gene retrocopies arise from the reverse transcription and insertion into the genome of processed mRNA transcripts. Although many retrocopies have acquired mutations that render them functionally inactive, most mammals retain active LINE-1 sequences capable of producing new retrocopies. New retrocopies, referred to as retro copy number variants (retroCNVs), may not be identified by standard variant calling techniques in high-throughput sequencing data. Although multiple functional FGF4 retroCNVs have been associated with skeletal dysplasias in dogs, the full landscape of canid retroCNVs has not been characterized. Here, retroCNV discovery was performed on a whole-genome sequencing data set of 293 canids from 76 breeds. We identified retroCNV parent genes via the presence of mRNA-specific 30-mers, and then identified retroCNV insertion sites through discordant read analysis. In total, we resolved insertion sites for 1911 retroCNVs from 1179 parent genes, 1236 of which appeared identical to their parent genes. Dogs had on average 54.1 total retroCNVs and 1.4 private retroCNVs. We found evidence of expression in testes for 12% (14/113) of the retroCNVs identified in six Golden Retrievers, including four chimeric transcripts, and 97 retroCNVs also had significantly elevated F ST across dog breeds, possibly indicating selection. We applied our approach to a subset of human genomes and detected an average of 4.2 retroCNVs per sample, highlighting a 13-fold relative increase of retroCNV frequency in dogs. Particularly in canids, retroCNVs are a largely unexplored source of genetic variation that can contribute to genome plasticity and that should be considered when investigating traits and diseases.
... welfare (Asher et al., 2009), i.e. to square up to the absurdity of some breeding standards (King et al., 2012). Breeding programs thus should focus on the internal causes of undesired traits and behaviors, rather than on eliminating these by external manipulations, because the latter approach may generate other, sometimes more urgent, welfare issues. ...
Animal welfare is a multifaceted issue that can be approached from different viewpoints, depending on human interests, ethical assumptions, and culture. To properly assess, safeguard and promote animal welfare, concepts are needed to serve as guidelines in any context the animal is kept in. Several different welfare concepts have been developed during the last half decade. The Five Freedoms concept has provided the basis for developing animal welfare assessment to date, and the Five Domains concept has guided those responsible for safeguarding animal welfare, while the Quality of Life concept focuses on how the individual perceives its own welfare state. This study proposes a modified and extended version of an earlier animal welfare concept - the Dynamic Animal Welfare Concept (DAWCon). Based on the adaptability of the animal, and taking the importance of positive emotional states and the dynamic nature of animal welfare into account, an individual animal is likely in a positive welfare state when it is mentally and physically capable and possesses the ability and opportunity to react adequately to sporadic or lasting appetitive and adverse internal and external stimuli, events, and conditions. Adequate reactions are elements of an animal’s normal behavior. They allow the animal to cope with and adapt to the demands of the (prevailing) environmental circumstances, enabling it to reach a state that it perceives as positive, i.e., that evokes positive emotions. This paper describes the role of internal as well as external factors in influencing welfare, each of which exerts their effects in a sporadic or lasting manner. Behavior is highlighted as a crucial read-out parameter. As most animals under human care are selected for certain traits that may affect their behavioral repertoire it is crucial to have thorough ethograms, i.e., a catalogue of specific behaviors of the species/strain/breed under study. DAWCon highlights aspects that need to be addressed when assessing welfare and may stimulate future research questions.
... Consequently, purebred dogs have a greater risk of suffering from genetic disorders than any other species 4 . A number of scientific publications have described the health problems of purebred dogs [5][6][7][8][9][10][11] and emphasized the need for action [9][10][11][12][13][14] ; the problem has also been highlighted recently in public media 15 . As a result, many breeders are increasingly using DNA tests to reduce the frequency of deleterious mutations in their breeding programs 4 . ...
Canine hip dysplasia (HD) is a multifactorial disease caused by interactions between genetic and environmental factors. HD, which mainly occurs in medium- to large-sized dogs, is a disease that causes severe pain and requires surgical intervention. However, the procedure is not straight-forward, and the only way to ameliorate the situation is to exclude individual dogs with HD from breeding programs. Recently, prime editing (PE), a novel genome editing tool based on the CRISPR-Cas9 system, has been developed and validated in plants and mice. In this study, we successfully corrected a mutation related to HD in Labrador retriever dogs for the first time. We collected cells from a dog diagnosed with HD, corrected the mutation using PE, and generated mutation-corrected dogs by somatic cell nuclear transfer. The results indicate that PE technology can potentially be used as a platform to correct genetic defects in dogs.
... The CFR had no statistically significant influence on being BOAS+ in the multivariable model. Nevertheless, since extreme brachycephaly is a risk factor for numerous other diseases [6,8], a benefit of breeding dogs with longer muzzles seems obvious. Additionally, as the nose plays a major role in thermoregulation [1], and several owners stated in our study questionnaire that their dogs suffered from heat intolerance, breeding for a lengthening of the muzzle might improve heat exchange in brachycephalic dogs [56]. ...
Despite efforts of veterinarians and breeders, brachycephalic obstructive airway syndrome (BOAS) is still a common problem in pugs, underlining the need for objective tests to identify and prevent breeding with affected dogs. In the current study, a submaximal, treadmill-based fitness test was evaluated as a tool to identify signs of airway obstruction not recognisable under rest conditions. In addition to this, different body conformation and measurements were assessed regarding their association with BOAS. A total of 62 pugs and 10 mesocephalic dogs trotted with an individual comfort speed on a treadmill for 15 min. Before and during the examination, dogs were examined for signs of respiratory distress, and a functional BOAS grading was applied. The influence of body conformation on BOAS grading was tested in a univariable and multivariable logistic regression model. During exercise, more respiratory noises were observed, and existing respiratory noises became more apparent in comparison to when at rest. In the multivariable logistic regression model, no factor had a statistically significant influence on BOAS classification. Submaximal fitness testing helped to identify signs of respiratory distress not apparent under resting conditions, and could be a valuable addition for identifying dogs with BOAS. Performing testing on a treadmill facilitates continuous observation of the patients, and enables standardisation of the test regarding the test environment, as well as provides an uninterrupted, steady workload.
... This finding was confirmed by the current study, where 3.9% of the English Bulldogs surveyed were diagnosed with entropion, and the breed showed a markedly increased odds ratio of 11.61 compared to dogs that are not English Bulldogs. Entropion, like skin fold dermatitis, is commonly seen in brachycephalic breeds and is generally attributed to the excess facial skin that results from a foreshortened facial structure; hence, it is usually considered a conformation related disease [55,56]. ...
Background
The English Bulldog has risen sharply in popularity over the past decade but its distinctive and extreme conformation is linked to several serious health conditions. Using multivariable analysis of anonymised veterinary clinical data from the VetCompass Programme, this study compared the odds of common disorders between English Bulldogs and all remaining dogs in the UK during 2016.
Results
From 905,544 dogs under veterinary care during 2016, the analysis included a random sample of 2,662 English Bulldogs and 22,039 dogs that are not English Bulldogs. English Bulldogs had 2.04 times the odds of diagnosis with ≥ 1 disorder than dogs that are not English Bulldogs (95% confidence interval [CI] 1.85 to 2.25). At a specific-level of diagnostic precision, English Bulldogs had increased odds of 24/43 (55.8%) disorders. These included: skin fold dermatitis (odds ratio [OR] 38.12; 95% CI 26.86 to 54.10), prolapsed nictitating membrane gland (OR 26.79; 95% CI 18.61 to 38.58) and mandibular prognathism (OR 24.32; 95% CI 13.59 to 43.53). Conversely, English Bulldogs had significantly reduced odds of 6/43 (14.0%) disorders. These included: retained deciduous tooth (OR 0.02; 95% CI 0.01 to 0.17), lipoma (OR 0.06; 95% CI 0.01 to 0.40) and periodontal disease (OR 0.23; 95% CI 0.18 to 0.30). At a grouped-level of diagnostic precision, English Bulldogs had significantly increased odds of 17/34 (50.0%) disorders. These included: congenital disorder (OR 7.55; 95% CI 5.29 to 10.76), tail disorder (OR 6.01; 95% CI 3.91 to 9.24) and lower respiratory tract disorder (OR 5.50; 95% CI 4.11 to 7.35). Conversely, English Bulldogs had significantly reduced odds of 3/34 (8.8%) disorders. These were: dental disorder (OR 0.25; 95% CI 0.20 to 0.31), spinal cord disorder (OR 0.31; 95% CI 0.14 to 0.71) and appetite disorder (OR 0.43; 95% CI 0.20 to 0.91).
Conclusions
These results suggest that the health of English Bulldogs is substantially lower than dogs that are not English Bulldogs and that many predispositions in the breed are driven by the extreme conformation of these dogs. Consequently, immediate redefinition of the breed towards a moderate conformation is strongly advocated to avoid the UK joining the growing list of countries where breeding of English Bulldogs is banned.
... 9 BC breeds have been linked to many inherited disorders which can affect quality of life and longevity, including BC obstructive airway syndrome (BOAS), dystocia, ophthalmic diseases, neurological diseases and dermatological conditions. [10][11][12][13][14] BOAS is a conformation-related respiratory disorder perpetuated by selective breeding for extreme brachycephaly. Affected dogs have deformation of their upper respiratory tract due to shortening of the skull without a proportional reduction in the soft tissues of the head. ...
Background:
The popularity of brachycephalic dogs continues to increase despite inherent breed health problems. Increased education of current and potential brachycephalic dog owners could reduce the desirability of severely affected dogs.
Methods:
Members of the general public were prospectively recruited to assess their understanding and opinions of brachycephalic breed-related health problems, before and after an educational intervention on brachycephalic obstructive airway syndrome (BOAS).
Results:
A total of 587 people participated. Before the intervention most participants considered characteristics of BOAS to be normal for brachycephalic dogs. Following the intervention this was moderately reduced. Responses highlighted that defining 'normal' for a breed is difficult. Referring to a trait as 'normal', even in a negative context results in normalisation. 99.7% of participants had an improved understanding of BOAS following the intervention. However, only 53.0% of the total participants and 29.3% of brachycephalic dog owning participants had their opinion of brachycephalic dogs changed. 99.5% of participants believed that potential owners should be more aware of BOAS and 57.3% of brachycephalic dog owners would have liked further information about breed health problems before purchasing their dog.
Conclusion:
Educational interventions may be beneficial in improving understanding and awareness of BOAS however, normalisation of clinical signs of BOAS remains prevalent.
... Consequently, purebred dogs have a greater risk of suffering from genetic disorders than any other species 4 . A number of scienti c publications have described the health problems of purebred dogs [5][6][7][8][9][10][11] and emphasized the need for action [9][10][11][12][13][14] ; the problem has also been highlighted recently in public media 15 . As a result, many breeders are increasingly using DNA tests to reduce the frequency of deleterious mutations in their breeding programs 4 . ...
Canine hip dysplasia (HD) is a multifactorial disease caused by interactions between genetic and environmental factors. HD, which mainly occurs in medium- to large-sized dogs, is a disease that causes severe pain and requires surgical intervention. However, the procedure is not straight-forward, and the only way to ameliorate the situation is to exclude individual dogs with HD from breeding programs. Recently, prime editing (PE), a novel genome editing tool based on the CRISPR-Cas9 system, has been developed and validated in plants and mice. In this study, we successfully corrected a mutation related to HD in Labrador retriever dogs for the first time. We collected cells from a dog diagnosed with HD, corrected the mutation using PE, and generated mutation-corrected dogs by somatic cell nuclear transfer. The results indicate that PE technology can potentially be used as a platform to correct genetic defects in dogs.
... The extent of the differences in odds ratios for these predispositions and protections was also considered. However, it is important to recognise that comparing the relative number of predispositions to protections cannot fully reflect breed health without consideration of the severity and duration of disorders with predispositions and protections [26] and also consideration of disorders that are related to conformation [62]. The propensity (degree) of difference between the overall health of a breed compared with the overall health of all remaining dogs could be used as one indicator of the degree of divergence of individual breeds from the mainstream of current dogs. ...
Background
The French Bulldog is a highly popular dog breed but is linked with many serious health issues. A holistic view of breed health in French Bulldogs would assist efforts to appreciate the overall health strengths and weaknesses in the French Bulldog and to take appropriate steps to mitigate these.
Based on random sampling of French Bulldogs and non-French Bulldogs under primary veterinary care during 2016 within the VetCompass Programme, a cohort study design was used to estimate the one-year (2016) period prevalence of the most commonly diagnosed disorders in each group. Risk factor analysis used multivariable logistic regression modelling methods.
Results
The analysis included 2,781 French Bulldogs and 21,850 non-French Bulldogs. French Bulldogs were younger (1.51 years, IQR 0.86 – 2.77 vs. 4.48 years, IQR 1.94 – 8.14) ( p < 0.001) and lighter (12.45 kg, IQR 11.00 – 14.03 versus 13.80 kg, IQR 8.10 – 25.12) ( p < 0.001) than non-French Bulldogs. Of 43 common specific-level disorders across both groups, French Bulldogs had significantly increased adjusted odds of 20/43 (46.5 %) disorders and significantly reduced adjusted odds of 11/43 (25.6 %) disorders compared to non-French Bulldogs. Highly predisposed disorders in French Bulldogs included stenotic nares (OR 42.14; 95 % CI 18.50 to 95.99; p < 0.001), Brachycephalic Obstructive Airway Syndrome (OR 30.89; 95 % CI 20.91 to 45.64; p < 0.001), aural discharge (OR 14.40; 95 % CI 9.08 to 22.86; p < 0.001), skin fold dermatitis (OR 11.18; 95 % CI 7.19 to 17.40; p < 0.001) and dystocia (OR 9.13; 95 % CI 5.17 to 16.13; p < 0.001). At a grouped-level of diagnostic precision, French Bulldogs had increased adjusted odds of 12/32 (37.5 %) disorders and reduced adjusted odds of 6/32 (18.8 %) disorders compared to non-French Bulldogs.
Conclusions
These results identified ultra-predispositions with worryingly higher odds in French Bulldogs for several disorders, suggesting that the health of French Bulldogs has diverged substantially from, and may be lower than, the health of the wider non-French Bulldog population. Many of these predispositions are closely associated with the conformational extremes that define the French Bulldog breed. Shifting the typical conformation of the French Bulldog population towards a more moderate phenotype is proposed as a logical opportunity to reduce the serious health issues endemic in the French Bulldog breed.
... Recent research on preferred dog breeds suggests that fashion, and not good sense, can drive the selection of specific breeds. In the United Kingdom, each of the top 50 dog breeds had at least one inherited disorder [52]. Additionally, dog breeds are not selected based on good health, longevity or good behavior (i.e. the most popular dogs are often those with high frequencies of genetic disorders and poor behavior) [53]. ...
Our research goal was to investigate the primate pet trade in the United States. While dogs and cats are the most common type of pet, there are an estimated 15,000 pet primates in the United States and the demand for exotic pets in general has been rising. Most research on pet primates occurs in habitat countries and little is known about these pets in the United States. We collected data from six exotic pet-trade websites twice a month for 12 months. We recorded the type of primate for sale, sex, age, location, and price. We used Chi-Square Goodness-of-Fit tests to compare whether the number of male and female pet primates for sale and the number of different age categories of pet primates for sale differed from equality and Spearman Correlation to examine associations between price and size and price and supply. We recorded 551 pet primates for sale between June 2019-June 2020, with 69.1% platyrrhines, 21.6% strepsirrhines, and 8.9% catarrhines. Marmosets were sold most often (36.7%, N = 202) followed by lemurs (21.6%, N = 119), capuchins (11.3%, N = 62), and squirrel monkeys (10.5%, N = 58). Almost two-thirds of the pet primates for sale were male (Chi-Square = 16.056, df = 1, P = 0. 00006) and 78.7% were under one year old (Chi-Square = 440.264, df = 2, P<0.00001). The median price was $3,800 though price was highly variable, even for the same taxa. There are several potential drivers for the primate pet trade, including media influence, fashion/status, and profitable breeding though these are not mutually exclusive. Primates do not make good pets and even when captive-bred, pet primates impact the conservation of their wild counterparts. Advertisement campaigns focusing on disease transmission and legal consequences and a federal ban on pet primate ownership are two avenues to pursue to end the ownership of pet primates in the United States.
... Some musculoskeletal pathologies are not incidental but the result of sustained and negligent breeding practices. These can include hip and elbow dysplasia in large and giant breeds, and odontoid process dysplasia, shoulder dysplasia and patellar luxation in small breeds (Asher et al., 2009). Simply providing a technological solution to an otherwise breeding problem, fails to address the underlying cause and transfers the societal responsibility to address it to the veterinary profession. ...
This book contains 15 chapters on biological limits of domestic animals. Topics discuses are: use new genetic technologies and animal breeding methods carefully to avoid problems (introduction); domestication to Dolly and beyond (a brief history of animal modification); good for whom (differences between human and animal enhancement); working equids (the welfare of those worked to their limit); genetics and other technologies for increasing the productivity of cattle, sheep and pigs (welfare implications); technologies for increasing the productivity of poultry (welfare implications); selective breeding, cloning and gene editing of dogs and cats for appearance and performance traits; methods to increase fish production (welfare and sustainability implications); welfare concerns in genetically modified laboratory mice and rats; cloning, editing and GMOs for animal enhancement; from bionic cat to superdog (ethical challenges of advanced prosthetic technology in veterinary medicine); animal welfare and the brave new world of modifying animals; a duty to the enhanced, not a duty to enhance (welfare responsibilities associated with domestication); pressing animals beyond their biological limits; and animals pushed to their limits (conclusion). This book is intended for farm owners and managers, geneticists, animal scientists, veterinarians and students.
... In internal medicine of small animals, many diseases affect specific breeds of dogs (GOUGH et al., 2018). In some of them, skull morphology can determine the predisposition of animals to some clinical signs (ASHER et al., 2009;CROCKER et al., 2020). In brachycephalic canine breeds (that is, with shorter rostrum-caudal lengths), such as Lhasa Apso, Shih-Tzu, English Bulldog, French Bulldog, Boston Terrier, Pekingese, Pug, and Boxer, the incidence of respiratory syndrome is high and it has been characterized by partial airway obstruction due to meatus nasi stenosis, stretching of pharynges (soft palate), and laryngeal collapse with ventriculus laryngis evertion (FASANELLA et al., 2010). ...
This paper aimed at reporting the creation of brachycephalic and dolichocephalic 3D synthetic anatomical models of canine heads (3D SAMCH) as a complementary technique to traditional osteotechnique using Computed Tomography (CT) images in volumetric reconstruction. The study was carried out in three stages, namely: a) preparation of canine heads in natura; b) creation of digital files of canine heads using CT; and c) 3D printing of synthetic anatomical models of canine heads. As a result, two 3D SAMCH were produced due to rarer availability in Animal Anatomy laboratories collections; the important representation of the cribriform plate was possible, but a remarkable defect presented was the teeth. It concluded that the digital files creation through CT scanner allows a fine representation of canine heads if considered pros and cons regarding the use of synthetic models instead of natural bones.
... Border Collies are one of the most popular breeds in the world with at least 25 known inherited disorders 1 . As more inherited disorders and causative mutations are identified, a major concern is the level of genetic diversity available in the population and the impact of removing carriers from the population through breeding management. ...
Maintaining genetic diversity in dog breeds is an important consideration for the management of inherited diseases. We evaluated genetic diversity in Border Collies using molecular and genealogical methods, and examined changes to genetic diversity when carriers for Trapped Neutrophil Syndrome (TNS) and Neuronal Ceroid Lipofuscinosis (NCL) are removed from the genotyped population. Genotype data for 255 Border Collies and a pedigree database of 83,996 Border Collies were used for analysis. Molecular estimates revealed a mean multi-locus heterozygosity (MLH) of 0.311 (SD 0.027), 20.79% of the genome consisted of runs of homozygosity (ROH ) > 1 Mb, effective population size ( N e ) was 84.7, and mean inbreeding (F) was 0.052 (SD 0.083). For 227 genotyped Border Collies that had available pedigree information (GenoPed), molecular and pedigree estimates of diversity were compared. A reference population (dogs born between 2005 and 2015, inclusive; N = 13,523; RefPop) and their ancestors (N = 12,478) were used to evaluate the diversity of the population that are contributing to the current generation. The reference population had a N e of 123.5, a mean F of 0.095 (SD 0.082), 2276 founders ( f ), 205.5 effective founders ( f e ), 28 effective ancestors ( f a ) and 10.65 (SD 2.82) founder genomes ( N g ). Removing TNS and NCL carriers from the genotyped population had a small impact on diversity measures (ROH > 1 Mb, MLH, heterozygosity), however, there was a loss of > 10% minor allele frequency for 89 SNPs around the TNS mutation (maximum loss of 12.7%), and a loss of > 5% for 5 SNPs around the NCL mutation (maximum 5.18%). A common ancestor was identified for 38 TNS-affected dogs and 64 TNS carriers, and a different common ancestor was identified for 33 NCL-affected dogs and 28 carriers, with some overlap of prominent individuals between both pedigrees. Overall, Border Collies have a high level of genetic diversity compared to other breeds.
... This is in line with a previous study suggesting that PL is associated with small body size and particularly small leg size. 39 In addition, all of these breeds are reported to be at increased risk of medial PL (MPL). 4,13,40 The fact that cruciate ligament rupture was among the top three diagnoses in all of these breeds could partly be due to the anatomical deviations associated with MPL, such as excessive internal rotation of tibia, which are suggested to increase the risk of CCLD. ...
Background:
Stifle joint diseases (SJD) are common in dogs and include a variety of diagnoses. The objective of the study was to provide an overview of the epidemiology of SJD in insured dogs.
Methods:
An historical single cohort study of dogs insured in Agria Pet Insurance (2011-2016) in Sweden was performed. Incidence and relative risk (RR) of SJD was calculated for the whole dog population and for subgroups divided by breed, breed group and sex.
Results:
The study population included almost 600,000 insured dogs (>1.7 million dog-years). Ninety-three different stifle joint diagnoses were reported in 9624 dogs, and the most common were cruciate ligament rupture and patellar luxation. The incidence of SJD was 55.4 cases per 10,000 dog-years at risk. Bulldog and boerboel had the highest RR of SJD. The breeds that accounted for the highest proportion of all SJD claimed dogs were mixed breed and Labrador retriever. Female dogs had a slightly increased RR compared with male dogs (RR 1.06, p = 0.006). The incidence increased yearly during the observation period.
Conclusion:
The study demonstrates breed-specific differences in incidence of SJD in dogs, which may be of importance for breeders, dog owners and veterinarians.
... And, indeed, this breed-focused approach is still a major plank of current health initiatives in dogs [37]. However, this breed-centric approach often tends to prioritise mitigation efforts on disorders that are either predisposed or perceived to have high genetic components within a breed above those that are common and modifiable, especially within the lifetime of the affected animals [12,36,[56][57][58]. Especially for disorders that have high severity and duration, greater welfare gains may result from even modest reductions in the frequency of common disorders compared with even large proportional reductions in rare disorders [12,36]. ...
Background
Although dogs are a commonly owned companion animal in the UK, the species experiences many health problems that are predictable from demographic information. This study aimed to use anonymised veterinary clinical data from the VetCompass™ Programme to report the frequency of common disorders of dogs under primary veterinary care in the UK during 2016 and to explore effects associated with age, sex and neuter status.
Results
From an available population of 905,543 dogs under veterinary care at 886 veterinary clinics during 2016, the current study included a random sample of 22,333 (2.47 %) dogs from 784 clinics. Prevalence for each disorder was calculated at the most refined level of diagnostic certainty (precise-level precision) and after grouping to a more general level of diagnostic precision (grouped-level precision). The most prevalent precise-level precision disorders recorded were periodontal disease (prevalence 12.52 %, 95 % CI: 12.09–12.97), otitis externa (7.30 %, 95 % CI: 6.97–7.65) and obesity (7.07 %, 95 % CI: 6.74–7.42). The most prevalent grouped-level disorders were dental disorder (14.10 %, 95 % CI: 13.64–14.56), skin disorder (12.58 %, 95 % CI: 12.15–13.02) and enteropathy (10.43 %, 95 % CI: 10.04–10.84). Associations were identified for many common disorders with age, sex and neuter.
Conclusions
The overall findings can assist veterinarians and owners to prioritise preventive care and to understand demographic risk factors in order to facilitate earlier diagnosis of common disorders in dogs. The information on associations with age, sex and neuter status provides additional contextual background to the complexity of disorder occurrence and supports targeted health controls for demographic subsets of dogs.
Dog ownership is an increasing aspect of veterinary practice in Iraq and it needs special attention since it lacks necessary information such as prevalence of various diseases and other basic information in this regard. In this study 258 dogs referred to a small animal private practice in 2015-6 in Baghdad were assessed. The mean ± SD of these dogs' age was 9.19 ±19.4 months and men presented more dogs than women (222 compared to 36). German shepherd dog was the most popular dog breed presented in this study while the most commonly presented health conditions were GI infections, Canine parvovirus, musculoskeletal conditions, respiratory infections, and canine distemper respectively. Additional 75 dogs were healthy and presented for check up and vaccination. Finally, German shepherd dogs were more likely to be presented with a disease compared to other breeds specially mixed breeds.
This study aimed to investigate the establishment of relationship between inbreeding and life expectancy in dogs. A dataset of N = 30,563 dogs sourced from the VetCom-pass™ Program, UK was made available by the Royal Veterinary College, University of London, containing information about breed and longevity and was subject to survival analysis. A Cox regression proportional hazards model was used to differentiate survivability in three groups of dogs (mongrel, cross-bred and pure breed). The model was found highly significant (p < 0.001) and we found that mongrel dog had the highest life expectancy, followed by cross-bred dogs with only one purebred ancestor and purebred dogs had the lowest life expectancy. A second Cox regression was also found highly significant (p < 0.001) differentiating the lifespan of different dog breed and correlating positively the hazard ratio and the Genetic Illness Severity Index for Dogs (GISID). The results show that survivability is higher in mongrel dogs followed by cross-bred with one of the ancestor only as a pure breed, and pure breed dog have the highest morbidity level. Higher morbidity is associated with higher GISID scores, and therefore, higher inbreeding coefficients. These findings have important implications for dog breeders, owners, and animal welfare organizations seeking to promote healthier, longer-lived dogs.
Mobility impairments associated with musculoskeletal diseases, such as osteoarthritis and degenerative joint disease, affect approximately 200,000 dogs annually and pose a notable challenge to canine health and welfare. Osteoarthritis causes the remodelling of synovial joints, alongside inflammation and impaired mechanical function which can be extremely debilitating. Secondary osteoarthritis commonly affects dogs and can be exacerbated by previous joint abnormalities, such as patellar luxation or cranial cruciate ligament rupture. Although musculoskeletal diseases can affect dogs of any age, the early subtle signs of gait abnormalities are perhaps missed by owners, thus, dogs may be in the latter stages of osteoarthritis progression when they are presented to veterinarians. Dogs showing subtle signs of gait abnormalities must be presented to veterinary practices for acute diagnosis to prevent long-term deterioration. Musculoskeletal diseases, such as osteoarthritis and degenerative joint disease, are commonly diagnosed via visible radiographic changes. However, veterinarians can use a combination of subjective and objective clinical scoring systems, such as clinical metrology instruments and gait assessment in conjunction with radiography to aid their diagnosis and longitudinal monitoring of musculoskeletal diseases. These scoring systems may be more sensitive to earlier signs of mobility impairments in dogs, ultimately, promoting increased canine health and welfare by enabling pain reduction, improvement of muscle strength and preservation of joint function. Current canine mobility scoring systems available to veterinarians will be discussed in turn throughout this review for implementation into clinical practice.
The factors influencing why and how people decide to acquire a dog are not well understood and little is known about the extent to which prospective owners undertake preparatory research. This study aimed to better understand what factors influence whether prospective dog owners in the UK conduct preparatory research. A 2019 online survey of current (n = 8050) and potential (n = 2884) dog owners collected quantitative and qualitative data. Additional qualitative data were collected through semi-structured interviews with current (n = 166) and potential (n = 10) dog owners. Of the current owners surveyed, 54% stated that they had looked for advice or information prior to acquiring their dog. Of potential owners, 68% reported already having looked for information, while a further 14% were planning to undertake research prior to acquiring a dog. Those with previous dog ownership experience were less likely to undertake pre-acquisition research, as were those who had worked with dogs. Demographic factors were also associated with the likelihood of conducting pre-acquisition research, with younger prospective owners being more likely to have undertaken research, as well as those with formal education qualifications. Among current owners, pre-acquisition research was more likely among those who acquired their dog through a breeder; a specific breed or a mix of two breeds; or as a puppy. Qualitative data were consistent with and added additional understanding and context to these findings. Almost half of current owners did not conduct pre-acquisition research, highlighting the need for increased awareness of its importance and the development of targeted interventions to encourage this activity. Understanding the different factors that influence whether dog owners undertake research may be of interest to animal welfare and veterinary organisations, in order to inform interventions to better prepare people for dog acquisition.
Objective:
To evaluate the effects of ala vestibuloplasty on cardiopulmonary and lifestyle-related parameters in brachycephalic (BC) cats.
Study design:
Prospective cohort.
Animals:
Client-owned BC cats (n = 19).
Methods:
Cats were assessed preoperatively by airway computed tomography (CT), endoscopy, contrast echocardiography, cardiac biomarkers, and structured owner questionnaire. Ala vestibuloplasty was performed bilaterally, and blood values, imaging, and owner questionnaire responses were re-evaluated 8-20 weeks postoperatively.
Results:
Cats were presented for predominantly respiratory clinical signs attributable to brachycephaly. Preoperatively, all cats had stenotic nares, prolonged normalized pulmonary transit time (nPTT) (mean 5.43 ± 1.10 s), and a hyperattenuating pulmonary pattern. No complications occurred following surgery. Postoperatively, nPTT (mean 3.89 ± 0.74 s, p < .001) and frequencies of sneezing (p = .002), snoring (p = .006), open-mouth breathing (p = .0004), and nasal discharge (p = .019) were decreased. Cats exhibited increased activity (p = .005), less frequent dyspnea during activity (p < .001), longer duration of activity before becoming dyspneic (p = .002), faster recovery from activity (p < .001), and decreased respiratory noise (p < .001). Median questionnaire scores improved from preoperative to postoperative (p < .001).
Conclusion:
Anatomic, echocardiographic, and CT changes were common in this cohort of clinically affected BC cats. Pulmonary blood flow and respiratory function were improved after surgery.
Clinical significance:
Stenotic nares are the predominant airway abnormality in BC cats. Ala vestibuloplasty is a safe procedure that improves cardiac and CT abnormalities and respiratory and other clinical signs in BC cats.
Purpose:
Severe entropion of the medial canthus results in ocular surface diseases and tear staining syndrome. However, detailed anatomical structures of the medial canthus and lacrimal ducts in dogs are poorly understood. We aimed to understand the anatomical structures of the medial canthus by analyzing the distances from the medial palpebral commissure to the superior lacrimal punctum (DSP) and to the inferior lacrimal punctum (DIP) and by histological examinations of the medial canthal anatomy.
Methods:
Dogs that underwent modified medial canthoplasty (MMC) between April 2017 and March 2021 were studied. As a reference, non-brachycephalic dogs that underwent other surgeries were also examined. DSP and DIP were measured preoperatively in all dogs in both the non-everted and everted positions. Histological examinations of the medial canthal anatomy were performed in four eyes isolated from beagles.
Results:
The ratios of DIP to DSP (mean ± SD) at the non-everted and everted positions in 242 MMC eyes of 126 dogs were 2.05 ± 0.46 and 1.05 ± 0.13, respectively (p < .01). The ratios of everted to non-everted positions for DIP and DSP were 0.98 ± 0.21 and 1.93 ± 0.49, respectively (p < .01). Histological findings indicated that the orbicularis oculi muscle (OOM) circumjacent lacrimal canaliculus transformed into collagen fibers and were attached to the lacrimal bone.
Conclusions:
Histological studies revealed that the OOM circumjacent lacrimal canaliculus transformed into collagen fibers and these collagen fibers may be related to the difference between DSP and DIP.
Epilepsy is a challenging multifactorial disorder with a complex genetic background. Our current understanding of the pathophysiology and treatment of epilepsy has substantially increased due to animal model studies, including canine studies, but additional basic and clinical research is required. Drug-resistant epilepsy is an important problem in both dogs and humans, since seizure freedom is not achieved with the available antiseizure medications. The evaluation and exploration of pharmacological and particularly non-pharmacological therapeutic options need to remain a priority in epilepsy research. Combined efforts and sharing knowledge and expertise between human medical and veterinary neurologists are important for improving the treatment outcomes or even curing epilepsy in dogs. Such interactions could offer an exciting approach to translate the knowledge gained from people and rodents to dogs and vice versa. In this article, a panel of experts discusses the similarities and knowledge gaps in human and animal epileptology, with the aim of establishing a common framework and the basis for future translational epilepsy research.
Brachycephalic Obstructive Airway Syndrome (BOAS) is a pathologic condition of the upper airways, frequently occurring in dogs of brachycephalic breeds including pugs. It has been suspected that BOAS may be associated with cardiovascular changes and an increased risk for hypertension. The cardiac biomarker NT-proBNP can help to differentiate cardiac from non-cardiac respiratory distress. A possible influence of BOAS on NT-proBNP values has not been investigated, however. The aim of the current study was to examine blood pressure and NT-proBNP levels in pugs with and without clinical signs of BOAS and compare them to values of mesocephalic dogs. For this purpose, NT-proBNP values of 42 pugs and six mesocephalic dogs and blood pressure measurements of 34 pugs and four mesocephalic dogs were explored in the present study. Pugs were examined for clinical signs of BOAS at rest and after a submaximal fitness test, and a functional BOAS grading was applied. Blood pressure (BP) was measured at the beginning and end of the study day and NT-proBNP values were obtained before and after exercise. Measured values of pugs with different degrees of clinical impairment due to BOAS were compared among each other as well as to the CG. In terms of systolic, mean, diastolic BP, and NT-pro BNP, there were no relevant differences between pugs and the CG and no obvious connection between the severity of BOAS symptoms and measured values. BP values of all groups were lower at the second measurement at the end of the study day. NT-proBNP measurements were higher after exercise. BP and NT-proBNP values in all groups were in agreement with commonly used reference ranges. In conclusion, the study adds evidence, that BP and NT-proBNP values did not differ between mesocephalic dogs and pugs with different levels of severity of BOAS but between the measurement times. Thus, in the present study, excitement and exercise seemed to have a greater influence on BP and NT-proBNP values than presence of BOAS symptoms or breed. Discovered values show that the commonly used reference ranges for BP and NT-proBNP are applicable in pugs. This indicates that NT-proBNP can be used to differentiate between cardiac and non-cardiac respiratory distress even in pugs with clinical symptoms of BOAS.
Background: Brachycephalic obstructive airway syndrome (BOAS) in dogs indicates a particular set of upper airway abnormalities found in brachycephalic dogs (e.g., French bulldogs). Stenotic nares is one of the primary BOAS-related abnormalities restricting the functional breathing of affected dogs. For severe stenosis, rhinoplasty is required to increase the accessibility of the external nostril to air; however, the specific improvement from surgery in terms of respiratory physiology and uptake of inhaled air has not been fully elucidated
Method: This study employed Computational Fluid Dynamics (CFD) simulations to evaluate the effects of different stenotic intensities on airflow patterns in a total of eight French bulldog upper airways. A bulldog with severe stenosis after surgery was included to examine the efficacy of the surgical intervention.
Results: The results showed homogeneous airflow distributions in healthy and mild stenosis cases and significantly accelerated airstreams at the constricted positions in moderate and severe stenosis bulldogs. The airflow resistance was over 20-fold greater in severe stenosis cases than the healthy cases. After surgery, a decrease in airflow velocity was observed in the surgical region, and the percentage of reduced airflow resistance was approximately 4%.
Conclusions: This study suggests impaired breathing function in brachycephalic dogs with moderate and severe stenosis. The results also serve as a reference for veterinarians in surgical planning and monitoring bulldogs’ recuperation after surgery.
Behavior can change as a result of medical problems or physiological changes, and behavior changes are likely to be the first signs of stress, disease, and poor welfare in any animal. If shelter operations, behavior, and/or medical staff identify behaviors that may have an underlying medical cause, they can be addressed immediately, relieving suffering and increasing the adoptability of the animal. Conversely, if medical conditions that cause or exacerbate problematic behaviors are missed, time may be wasted on training or attempted behavior modification, thus prolonging suffering and time spent in the shelter. Only by safeguarding both physical and emotional health can we improve overall quality of life for animals in our care, facilitate their placement in homes, and help prevent their return to the shelter.
Our relationship with dogs runs thousands of years deep. Today, we might know dogs intimately as members of our human family, but we can also know and consider dogs on their own terms, as members of Canis familiaris , with a unique evolutionary history and species‐specific characteristics and needs. This chapter is a resource for all types of dog knowers and caretakers. It relies heavily on empirical research to anchor readers in the foundations of canine behavior—such as dog behavioral development, normal dog behavior, factors influencing behavior, and relationships with people—and considers how these topics affect dogs of all ages and backgrounds who find themselves in the shelter environment.
This article discusses updates in brachycephalic and other upper respiratory surgery of dogs and cats, including schemata for classifying brachycephalic dogs in terms of severity of disease and indications for monitoring and treatment, new characterizations of the primary and secondary components of brachycephalic obstructive airway syndrome (BOAS), and updates to traditional brachycephalic airway surgical procedures as well as novel surgeries to treat BOAS, including laser-assisted turbinectomy, the cardiopulmonary effects of brachycephaly on some feline breeds, epiglottic entrapment and retroversion, and upper airway syndrome in Norwich terriers.
OBJECTIVE
To evaluate the frequency of ophthalmic disorders in 7 brachycephalic dog breeds referred to an academic veterinary ophthalmology service.
ANIMALS
970 client-owned dogs of 7 brachycephalic breeds that were evaluated by the ophthalmology service in a veterinary teaching hospital from January 2008 through December 2017.
PROCEDURES
Medical records of 7 brachycephalic breeds (ie, Boston Terriers, English Bulldogs, French Bulldogs, Lhasa Apsos, Pekingese, Pugs, and Shih Tzus) were reviewed to collect data regarding patient signalment, ophthalmic diagnoses, affected eyes, and number and dates of visits.
RESULTS
Median age at the first examination was 7 years (range, 23 days to 22 years). The number of dogs seen for a first examination increased with age. Corneal ulcers, keratoconjunctivitis sicca, corneal pigmentation, immature cataracts, and uveitis were each diagnosed in ≥ 100 dogs and represented 40.4% (1,161/2,873) of all diagnoses. On the basis of anatomic location, 66.3% (1,905/2,873) of all disorders were located in either the cornea (1,014/2,873 [35.2%]) or adnexa (891/2,873 [31%]). There was a significant difference in breed proportion in the study population; of the 7 breeds studied, Shih Tzus (34.3% [333/970]), Pugs (20.8% [202/970]), and Boston Terriers (16.6% [161/970]) were the most prevalent breeds. The frequency of some diseases within the referral population was associated with breed.
CONCLUSIONS AND CLINICAL RELEVANCE
Findings suggested that the most prevalent disorders for the brachycephalic breeds in this ophthalmic referral population were corneal ulcers, keratoconjunctivitis sicca, corneal pigmentation, immature cataracts, and uveitis. Although all dogs shared brachycephalic features, the frequency of specific ophthalmic diseases varied between breeds.
The definition of a purebred animal, from a scientific perspective, is based on a description of biological parameters and relates to animals having both parents of the same breed or variety, denoting a pure strain obtained through many generations of controlled breeding for desirable traits. In Europe there is a legal definition of what is a purebred. It refers to animals of a breed reared within the framework of a breeding program, which are eligible for registration with a recognized club or society keeping a register of animals of that breed, in order to obtain a pedigree or zootechnical certificate.
However, such a definition is applicable to livestock animals and does not cover companion animals. This regulatory gap opens up to uncontrolled breeding of 'purebred' dogs and cats, which can jeopardize animal health more than even recognized breeders do, to a certain degree, as well as allow fraud. In Italy this gap has been filled by making dogs and cats covered by the legal definition of purebred animals as ‘pedigreed animals’. The law which provides for it is little known even in Italy, however, and generally not enforced. This work will propose the application of legal provisions on the breeding of purebred animals to dogs and cats, by adopting a binding framework at European level in order to make more controllable the work of people involved in this activity and to better protect animals.
The goals of this project were to quantify medical problems among a population of Military Working Dogs (MWDs) and analyze factors associated with common medical conditions. Medical conditions recorded in veterinary Master Problem List (MPL) entries for 774 young, non-deployed, active MWDs were categorized and combined with demographic information to analyze risk factors. Most dogs were male (74%), German Shepherd (39%) or Belgian Malinois (31%) breeds, certified in Explosive Detection (60%), and had a dark coat color (83%). Ages ranged from one to six years, with an average of 2.6 years (± 0.5 years). Eighty-three percent of dogs had a non-surgical medical problem in their record. The most common non-surgical medical problems were dermatologic (25% of MPL entries), alimentary (21%), dental (15%), soft-tissue injury (10%), and musculoskeletal conditions (4%). Factors associated with each medical condition were breed (Odds Ratios 1.96-8.24), sex and spay/neuter status (ORs 1.78-5.77), occupational duty certification (ORs 2.65-3.62), military command location (ORs 2.32-7.44), and military branch (OR 5.16). As MWDs are a valuable asset for the Department of Defense, training and work conditions for the identified at-risk groups of MWDs should be further assessed to maximize their operational capabilities and assess the potential to serve as sentinel indicators for human diseases. Improved understanding of the most common medical problems affecting MWDs, and the identification of factors associated with these conditions, can help drive changes in their preventive care.
Background:
Canine leishmaniosis (CanL) is a common infectious disease. Age, sex and breed might influence the type of clinical and pathological manifestations that dogs develop. The main objective of this retrospective cross-sectional study was to determine if an association between age, sex, breed and size and the clinical findings of CanL exists.
Material and methods:
Dogs with a diagnosis of leishmaniosis were enrolled (n = 123). Clinical information, including signalment, clinical signs and laboratory abnormalities, was retrieved from medical records from different veterinary facilities from Catalonia.
Results:
Young dogs developed less frequently systemic signs (p = 0.0046), renal (p = 0.0019) and haematologic (p = 0.0275) abnormalities, while dermatologic signs were more common in young and adult dogs compared with old ones (p = 0.0451). Young dogs showed proteinuria less often than adult and old dogs (p = 0.0029). Young dogs did not present renal azotemia, while old dogs showed occasionally renal azotemia (p = 0.0478). Young dogs were mainly classified as mild-moderate LeishVet clinical stages of the disease, and very rarely as severe-very severe LeishVet clinical stages, compared with adult and old dogs (p = 0.0457). Purebred dogs significantly developed ulcerative dermatitis more frequently than crossbred dogs (p = 0.0460).
Conclusion:
This study describes that age is associated with differences in clinicopathological findings of CanL.
American Cocker Spaniels (ACSs) develop aural ceruminous gland hyperplasia and ectasia more often than dogs of other breeds. Data on the cause and development of these breed characteristic histopathological changes are lacking. We performed video-otoscopic examinations and dermatological work-up on 28 ACSs, obtained aural biopsies from each dog and assessed the statistical associations between the presence of ceruminous gland hyperplasia and ectasia and disease history, clinical or microbiological findings and underlying cause of otitis externa (OE). Histological lesions of ceruminous gland hyperplasia and ectasia were observed in aural biopsies from 6/13 clinically healthy ears and 13/15 ears with OE from 19/28 examined dogs. Nine of 28 dogs had histologically normal ceruminous glands (odds ratio [OR] 6.2, 95% confidence interval [CI] 1.1–36.6). Bacterial growth in microbiological culture of aural exudate (OR 14.1, 95% CI 2.1–95.3) was associated with ceruminous glandular changes, whereas previous history of OE, cutaneous findings or underlying allergies were not. Pedigree analysis and a genome-wide association study (GWAS) were performed on 18 affected and eight unaffected dogs based on histopathological diagnosis. While the GWAS indicated a tentative, but not statistically significant, association of ceruminous gland hyperplasia and ectasia with chromosome 31, a larger cohort is needed to confirm this preliminary result. Based on our results, ceruminous gland hyperplasia and ectasia may also precede clinical signs of OE in ACSs and a genetic aetiological component is likely Further studies with larger cohorts are warranted to verify our preliminary results.
Dermoid (pilonidal) sinuses are defects of the dorsal midline skin that extend as blind sacs ventrally into the subcutaneous tissues. In some animals, these sinuses penetrate through the vertebral lamina and Into the dura mater, predisposing the animal to infection and neurologic abnormalities. Treatment includes surgical resection and antibiotic therapy based on culture and sensitivity. Because this disease is considered inherited in Rhodesian Ridgebacks, affected animals should not be bred.
The effect that breed standards and selective breeding practices have on the welfare of pedigree dogs has recently come under scrutiny from both the general public and scientific community. Recent research has suggested that breeding for particular aesthetic traits, such as tightly curled tails, highly domed skulls and short muzzles predisposes dogs with these traits to certain inherited defects, such as spina bifida, syringomyelia and brachycephalic airway obstruction syndrome, respectively. Further to this, there is a very large number of inherited diseases that are not related to breed standards, which are thought to be prevalent, partly as a consequence of inbreeding and restricted breeding pools. Inherited diseases, whether linked to conformation or not, have varying impact on the individuals affected by them, and affect varying proportions of the pedigree dog population. Some diseases affect few breeds but are highly prevalent in predisposed breeds. Other diseases affect many breeds, but have low prevalence within each breed. In this paper, we discuss the use of risk analysis and severity diagrams as means of mapping the overall problem of inherited disorders in pedigree dogs and, more specifically, the welfare impact of specific diseases in particular breeds.
This paper aimed to present the first results of an explorative screening program currently running in Italy and focussing on the prevalence of a specific orthopaedic disorder, elbow dysplasia (ED), in some breeds of dogs commonly reared in Italy. Data consisted of radiographic findings taken on 1370 dogs (758 females and 612 males) of 6 breeds (Bernese Mountain dog, Cane Corso, German Shepherd , Golden Retriever, Labrador Retriever and Rottweiler) screened at an age of 20.6 ± 11.6 months. Radiographs were graded for both ED and hip dysplasia (HD) according to a four- (0 to 3) or a five-grade (A to E) linear system, respectively. Logistic regression analysis was used for studying the relationships between breed, sex, age of dogs at screening and HD diagnosis with the outcome of the diagnosis for ED. Prevalence of ED (ED score ≥ 1) for the pool of breeds involved was 25%, and Labrador Retriever (17%) and Rottweiler (40%) showed, respectively, the lowest and the highest prevalence of ED among breeds in the study. Prevalence of HD (grades C or high- er) approached 15%. When compared to other breeds, Rottweiler and Bernese Mountain dogs showed significantly high- er risk to be affected by ED (odds ratio 3.2 and 3.0, respectively). Conversely, sex did not significantly affect the onset of ED. When compared to the youngest group of dogs at screening (average: 14 months), the oldest group of screened dogs (average: 40 months) exhibited a significantly higher risk of being diagnosed as affected by ED (odds ratio: 1.9). A negative status of hip joints appeared positively associated with a negative status of elbow joints, and dogs diagnosed as affected by HD had a 40% increased risk of being diagnosed as affected by ED. In conclusion, results from this study demonstrated that ED has a noticeable prevalence in some Italian dog populations, particularly in heavy breeds. Screening of dogs for ED appeared feasible and should be performed at a standard age. Phenotypic association between hip and elbow dysplasia observed in this study suggests that the genetic relationships between these skeletal disorders should be investigated.
This thesis is the cumulation of over a decade of study into the pathogenesis and treatment Chiari-like malformation and syringomyelia (CM/SM) in the cavalier King Charles spaniel (CKCS). Chiari-like malformation is a condition where the brain is too big for the skull and is crushed and pushed out the foramen magnum. This obstructs the flow of cerebrospinal fluid in and out of the head. A consequence of this is that fluid accumulates within the spinal cord forming cavities termed syringomyelia (SM). This fluid often collects in the dorsal horn of the spinal cord - an important area for collating information about pain sensation. The damage can result in signs of severe pain. As the dogs with this condition are a natural occurring example of a disease which also occurs in humans, finding new and effective ways of managing this pain will be relevant for both human and canine sufferers. CM/SM is inherited in the CKCS - as many as 50% have the condition and approximately 35% of affected dogs have clinical signs of pain. Part on the ongoing work in this study is the identification of the genes responsible for CM/SM.
Conventional methods for classifying patients with respect to utilization of health care resources are based almost exclusively on diagnostic criteria. We review a new severity of illness index which is generic to most medical and surgical conditions in a hospital, and which has been found to produce subgroups of patients more homogeneous with respect to hospital resource use (as assessed by total charges, length of stay, routine charges, and laboratory charges) than diagnostic-related groups, staging, and generalized patient management paths. We use the severity of illness groups to compare total charges and length of stay across hospitals. We find that charges and length of stay in an academic teaching hospital are similar to those in community hospitals with and without teaching programs when controlling for severity of illness. (Am J Public Health 1983; 73:25-31.)
Using histology, a coat color abnormality and the subsequent hair loss were diagnosed as black hair follicular dysplasia. A pedigree analysis of an affected litter and literature review suggests that this is inherited as an autosomal recessive trait. The melanocyte stimulating hormone receptor gene is ruled out by using linkage analysis.
Although aural neoplasia is a relatively uncommon entity in companion animals, it remains a group of heterogeneous conditions that can have a significant negative impact on quality and duration of life of dogs and cats. Chronic ear disease that responds poorly or partially to empiric therapy should raise the suspicion that an underlying condition, such as neoplasia, may be the perpetrator of inflammation. Early diagnosis followed by appropriate therapy improves the likelihood of disease control and prolonged survival.
Several neurological syndromes have been described in Cavalier King Charles spaniels and many of the conditions have similar clinical signs. The current knowledge of these syndromes is reviewed in this article, with the aim of enabling the general practitioner to formulate a differential diagnosis and plan for diagnostic tests and treatment. Specifically, the article discusses and contrasts the most common conditions seen, Including occipital hypoplasia/syringomyelia, episodic collapse, epilepsy and vestibular disorders.
To define the mode of inheritance of the dorsal ridge and investigate if the ridge predisposes to the congenital abnormality dermoid sinus in the Rhodesian ridgeback.
Segregation analysis was performed, including 87 litters (n=803) produced in Sweden between 1981 and 2002. Data were corrected to avoid bias in the segregation ratio. Chi-squared analysis was performed including 402 litters (n=3598) for the evaluation of a possible genetic correlation between the ridge and dermoid sinus.
The ridge is inherited in an autosomal dominant mode and predisposes for dermoid sinus. The frequency of ridgeless offspring in the Swedish Rhodesian ridgeback population is estimated to be 5.6 per cent.
Rhodesian ridgeback dogs that carry the ridge trait are predisposed to dermoid sinus.
To evaluate long-term success of cranial cervical decompression for management of canine Chiari-like malformation with syringomyelia (CM/SM).
Retrospective clinical study.
Cavalier King Charles spaniels (n=15).
After diagnosis by magnetic resonance imaging (MRI) dogs had cranial cervical decompression with durotomy. Seven dogs had the durotomy patched with biocompatible collagen matrix. Clinical outcome was monitored for >12 months.
All dogs either improved (80%) or were unchanged (20%) postoperatively. Postoperative MRI in 6 dogs revealed persistence of syringomyelia. Seven dogs (47%) subsequently deteriorated, 0.2-2.3 years after surgery (mean, 1.3 years) and 2 dogs were eventually euthanatized as a consequence. Twelve dogs were still alive, 1-6.5 years after surgery (mean, 2.5 years).
Cranial cervical decompression surgery is associated with low mortality and morbidity, and results in clinical improvement in most dogs. The procedure seemingly does not result in syrinx collapse and resolution. Clinical improvement may not be sustained and some dogs can be expected to deteriorate. Clinical
Cranial cervical decompression surgery may have a role in management of CM/SM. In dogs with severe pain, it can improve quality of life for several years; however, it does not appear to adequately address the primary cause of syringomyelia. Further prospective study is needed to better understand the pathogenesis and treatment of this disorder. Because this condition causes neuropathic pain but does not necessarily result in euthanasia more information is needed on appropriate pain management for these patients.
The dorsal hair ridge in Rhodesian and Thai Ridgeback dogs is caused by a dominant mutation that also predisposes to the congenital developmental disorder dermoid sinus. Here we show that the causative mutation is a 133-kb duplication involving three fibroblast growth factor (FGF) genes. FGFs play a crucial role in development, suggesting that the ridge and dermoid sinus are caused by dysregulation of one or more of the three FGF genes during development.
Based on a radiographic and morphologic study the incidence of mainly congenital changes of the vertebral column was evaluated in 228 necropsied pure-bred dogs of 52 different breeds. A total of 182 varieties were present in 116 of the 228 dogs. 37 dogs (16.22 %) showed variations from the normal number of cervical, thoracic, lumbar, or sacral vertebrae. Caudal articular surfaces or processes of thoracic vertebrae were missing in 39 dogs (17,10 %), most commonly affected were Pekingese (100 %), miniature poodle (100 %), Yorkshire terrier (80.00 %) and Maltese (66,66 %). On the contrary additional articular surfaces of cervical and lumbar vertebrae were noted only in large dogs. Cervical ribs and additional or missing thoracic ribs as well as fusion between ribs and thoracic vertebrae were found in a total of 26 dogs (11.40 %). Thoracolumbar cuneiform shaped vertebrae with their base directed dorsally were present in 52.94% of the Dachshunds. In contrast, cuneiform shaped vertebrae with their base directed ventrally were noted in the cranial and middle region of the thoracic vertebral column in 8 dogs without priority to any breed. Fusion between ilium and sacrum was present in 10 dogs (4.38 %), German Shepherd Dogs were most commonly affected. Block vertebrae of caudal thoracic vertebrae occurred in 3 dogs, Spina bifida of cranial thoracic vertebrae was also noted in 3 cases. A total of 13 dogs had transitional vertebrae, they were found at the junction between segments as well as within the cervical segment. Single findings were pronounced konvex cranial extremities of cervical vertebrae, the immoderate enlargement of the vertebral canal in the cervical and lumbar segment, strikingly round edges of thoracic vertebral end plates, fractured thoracic vertebral end plates and unusually pronounced central depressions on lumbar vertebral end plates. Besides, signs of ossified pachymeninx were present in the cervical or lumbar segment of 5 dogs.
† The Global Assessment Scale (GAS) is a rating scale for evaluating the overall functioning of a subject during a specified time period on a continuum from psychological or psychiatric sickness to health.In five studies encompassing the range of populations to which measures of overall severity of illness are likely to be applied, the GAS was found to have good reliability. GAS ratings were found to have greater sensitivity to change over time than did other ratings of overall severity or specific symptom dimensions. Former inpatients in the community with a GAS rating below 40 had a higher probability of readmission to the hospital than did patients with higher GAS scores.The relative simplicity, reliability, and validity of the GAS suggests that it would be useful in a wide variety of clinical and research settings.
This paper reviews the history of the establishment of dog breeds, summarizes current health and resultant welfare problems and makes some positive suggestions for their resolution. Some breed standards and selection practices run counter to the welfare interests of dogs, to the extent that some breeds are characterized by traits that may be difficult to defend on welfare grounds. Meanwhile, little selection pressure seems to be exerted on some traits that would improve animal welfare and produce dogs better suited to modern society. Unfortunately, the incidence of certain inherited defects in some breeds is unacceptably high, while the number of registered animals of certain breeds within some countries is so low as to make it almost impossible for breeders to avoid mating close relatives. There are several constructive ways to overcome these challenges. Breed associations can ensure that reduction of welfare problems is one of their major aims; they can review breed standards; they can embrace modern technology for animal identification and pedigree checking; they can allow the introduction of 'new' genetic material into closed stud-books; and they can encourage collaboration with geneticists in identifying and using DNA markers for the control of inherited disorders. There should be a concerted effort to produce and evaluate as companion animals first-cross (F1) hybrids from matings between various pairs of breeds. Finally, geneticists must learn to communicate their science better and in a language that non-geneticists can understand.
DEGENERATIVE intervertebral disc disease is the most common spinal disorder in the dog. This article discusses the pathophysiology of intervertebral disc and spinal cord disease, the associated historical and clinical features, differential diagnoses and aids to diagnosis. A second article, to be published in the next issue, will focus on the management options for dogs with intervertebral disc disease.
Many breeds of companion animal have inherited disorders that may impair quality of life (QoL) to the extent that it is unkind to keep them alive. If we struggle to discern when this point is reached, why do we breed compromised, short-lived animals in the first place? If we struggle to judge when environmental conditions cause an unacceptable QoL, why not breed appropriately for modern environments? In breeding pedigree dogs, five major problems arise: (1) some breed standards and selection practices run counter to dog welfare; (2) insufficient selection pressure seems to be exerted on some traits that would improve animal well-being and produce dogs better suited to modern environments; (3) the incidence of certain inherited defects in some breeds is unacceptably high; (4) the dearth of registered animals of certain breeds in particular countries makes it extremely difficult for breeders to avoid mating close relatives; and (5) there may be financial disincentives for veterinarians to reduce the incidence of inherited diseases. Before we can judge when behavioural or morphological changes caused by selective breeding result in an unacceptable QoL, we have to know which are prevalent. This paper reviews progress in two Australian schemes to monitor trends in the prevalence of inherited disorders in dogs and to promote behavioural phenotypes likely to cope with contemporary domestic environments.
Abstract— The preliminary results of an investigation into the existence of certain deleterious conditions that are, or may be, hereditary are presented. Thirteen conditions were found to be of major concern and of these five were considered to be of importance and needing immediate consideration. They are hip dysplasia, patella luxation, entropion, retinal atrophy, and prolonged soft palate. The second priority group consists of abnormal temperament, skin fold dermatitis, uterine inertia, elbow dysplasia, ectropion, trichiasis, and deafness.The report was prepared from 104 record forms completed over a period of 6 months by veterinary surgeons in practice.Résumé— Les résultats préliminaires sont présent& d' une étude se rapportant à certains états pathologiques dont L' étiologie serait héréditaire. Treize d' entre dux sont considérés comme étant d' importance majeure, et cinq de ceux-ci comme méritant une étude immédiate. Ce sont la dysplasie de la hanche, la luxation de la rotule, L' entropion, L' atrophie rétinienne, L' extension du voile du palais, la dysplasie du conde, L' ectropion, la trichiasis et la surditité.Le rapport a été préparéà partir de 104 formulairee tenus à jour pendant six mois par des vétérinaires pratiquants.Zusammenfassung— Es werden die vorläufigen Ergebnisse einer Untersuchung des Vorhandenseins gewisser schädlicher Zustände dargelegt, die erblich oder nicht erblich sein können. Es wurde festgestellt, dass dreizehn Zustände von besonderer Bedeutung sind, von denen fünf als wichtig angesehen werden mussen und sofortige Aufmerksamkeit erheischen. Diese sind Dysplasie der Hüfte, Luxation der Kniescheibe, Entropion, Atrophie der Netzhaut, weicher Gaumen f¨r länger als natürliche Zeitspanne, Dysplasie des Ellenbogens, Ektropion, Trichinose und Taubheit.Der Bericht wurde aus 104 Formularen mit Befunden zusammengestellt, die während eines Zeitraums von sechs Monaten von praktizierenden Tierärzten ausgefüllt worden waren.
The case records of 58 German Shepherds (GS group) affected by mitral valve prolapse (MVP) and/or mitral valve regurgitation (MR), and 49 dogs weighing < 15 kg (D group), affected by chronic valvular disease (CVD) were reviewed. The dogs of the GS group were presented more often without a detectable heart murmur (p < 0.01), and less frequently with a high intensity heart murmur (p < 0.01). Atrial fibrillation (AF) was more common in the GS group (p < 0.001). MVP associated with mitral valve thickening was more common in the D group (p < 0.001). Fractional shortening (FS) was lower (p < 0.0001) and end-systolic volume index (ESV-I) was increased (p < 0.0001) in the GS group, whereas end-diastolic volume index (EDV-I) did not differ between the 2 groups. Prevalence and severity of pulmonary hypertension were similar in the 2 groups. Dogs with mitral valve disease weighing more than 20 kg had a 5.8 higher chance of developing decreased FS, increased ESV-I, AF and ventricular arrhythmias. In the GS group, the decreased FS and increased ESV-I were not associated with the presence of AF or ventricular arrhythmias (p > 0.05). It appears that GS may be affected both by mitral valve prolapse and mitral insufficiency. It also appears that a comparatively large proportion of GS shows no major mitral valve thickening or MVP, but still presents with significant mitral regurgitation, possibly suggesting a different cause for the important incompetence observed in most cases.
The Global Assessment Scale (GAS) is a rating scale for evaluating the overall functioning of a subject during a specified time period on a continuum from psychological or psychiatric sickness to health. In five studies encompassing the range of population to which measures of overall severity of illness are likely to be applied, the GAS was found to have good reliability. GAS ratings were found to have a greater sensitivity to change over time than did other ratings of overall severity or specific symptom dimensions. Former inpatients in the community with a GAS rating below 40 had a higher probability of readmission to the hospital than did patients with higher GAS scores. The relative simplicity, reliability, and validity of the GAS suggests that it would be useful in a wide variety of clinical and research settings.
The prevalence of chronic valvular disease was studied in 494 cavalier King Charles spaniels with a mean (+/- sd) age of 3.0 +/- 2.7 years. Cardiac murmurs were detected in 65 (13.2 per cent) of the dogs. Among 61 cavalier King Charles spaniels with a mean age of 6.4 +/- 2.8 years, cardiac murmurs were detected in 32 (52 per cent). In both groups of dogs the prevalence of cardiac murmurs was low among dogs younger than three years (1.9 per cent) but increased with age (P < 0.001). The estimated ages at which 50 per cent of the dogs had developed murmurs were 7.5 and 6.2 years, respectively. When 39 of the 61 dogs were re-examined three years later, cardiac murmurs were detected in 28 (72 per cent), and the intensities of the murmurs had generally increased (P < 0.05). Nine (28 per cent) of the dogs which had previously had murmurs had been euthanased for signs of congestive heart failure whereas none of the dogs which had been free of murmurs had died from congestive heart failure. Animal insurance statistics from 1982 to 1990 (1983 excluded) for dogs less than 10 years old showed that claims for veterinary care or death or euthanasia were five times more common in the cavalier King Charles spaniel than in dachshunds (P < 0.001) and eight times more common than the mean for all other insured breeds (P < 0.001).
Application of generic and specific measures of health status and quality of life to different diseases, conditions, states, and populations is increasing. Four strategies for using these measures are separate generic and specific measures, modified generic measures, disease-specific supplements, and batteries. The preferred strategy depends on project aims, methodological concerns, and practical constraints. Generic measures are necessary to compare outcomes across different populations and interventions, particularly for cost-effectiveness studies. Disease-specific measures assess the special states and concerns of diagnostic groups. Specific measures may be more sensitive for the detection and quantification of small changes that are important to clinicians or patients. Comparison studies are needed of the validity, reliability, and responsiveness of generic and disease-specific measures in the same population and in minority and age-specific groups.
A retrospective study of 8975 dogs seen at 15 university veterinary medical teaching hospitals in North America (1975 to 1978) found that dogs with pendulous ears and heavy ear canal hair had significantly (P less than 0.01) more otitis externa than dogs with other ear types. Dogs with erect ears, regardless of the amount of ear canal hair, had less risk (P less than 0.01) of the disease than mongrel dogs. Direct evidence is available for the first time showing that monthly variations in ambient temperature, rainfall and relative humidity explain, to a large extent, the monthly variations in the hospital prevalence of canine otitis externa in different geographic regions.
To compare the performances of a disease-specific severity of illness index and a prototypical generic severity of illness measure, MedisGroups Admission Severity Groups (ASGs), for patients with community-acquired pneumonia.
A retrospective database study.
Adult patients (aged > or = 18 years) with an ICD-9-CM principal diagnosis of pneumonia in 78 MedisGroups Comparative Database hospitals.
The pneumonia severity of illness index (PSI) was developed to predict hospital mortality using logistic regression analyses in a 70% random sample of study patients. The performances of the PSI and the generic severity measure were assessed among the remaining 30% of patients by comparing observed mortalities within the five PSI and ASG severity classes, and areas under their receiver operating characteristic (ROC) curves. Both the PSI and the generic severity measure were used to estimate the 95% confidence interval of the expected number of deaths in each of the 78 study hospitals. Hospitals with an observed number of deaths outside these limits were identified as outliers.
There were 14,199 study patients who had community-acquired pneumonia, and 1,542 (10.9%) died during hospitalization. In comparison with the generic severity measure, the PSI more accurately identified patients at extremely low risk of death, and had a larger area under its ROC curve (0.84 vs 0.79; p < 0.0001). Of the 78 study hospitals, 17 (21.8%) were classified as outliers for mortality by at least one severity adjustment system. Among the 11 low-outlier hospitals, six were classified by the generic severity measure alone, two by the PSI alone, and three by both systems; among the six high-outlier hospitals, one was classified by the generic measure alone, three by the PSI alone, and two by both systems.
The PSI provided more accurate estimates of hospital mortality and classified different hospital outliers for mortality than did the generic severity of illness measure for patients with community-acquired pneumonia.
Peripheral deafness may be inherited or acquired, congenital or later-onset, and sensorineural or conductive. The most commonly observed forms are inherited congenital sensorineural, acquired later-onset sensorineural (ototoxicity, presbycusis) and acquired later-onset conductive (chronic otitis externa/media). In most dog and cat breeds inherited congenital sensorineural deafness results from perinatal degeneration of the stria vascularis, the vascular bed of the outer wall of the cochlear duct, which leads to hair cell degeneration. The strial degeneration appears to result from the absence of melanocytes, but their function in this structure is unknown. Ototoxicity may result from any of a large number of drugs and chemicals that directly or indirectly destroy cochlear hair cells. The effects are dose-dependent and in rare cases reversible. The most commonly recognized ototoxic drugs are the aminoglycoside antibiotics. Presbycusis, the ageing-related progressive hearing loss unattributable to other causes, is sensorineural but may also include mechanical changes in the tympanum and ossicles. Hearing aids may be accepted by some dogs as long as some residual function remains. Breeds reported to have been affected by congenital sensorineural deafness are listed and those with the highest prevalence are noted. Methods for diagnosis of deafness are described.
Histopathological and immunohistochemical examination of skin biopsies from 32 dogs with demodicosis is reported. There was no association between the different clinical presentations of the disease and the histopathological character of the biopsies, which included absence of inflammation (n = 2), dominant perifolliculitis (n = 11), interface mural folliculitis (n = 7), mural folliculitis (n = 1), furunculosis (n = 10) and nodular dermatitis (n = 1). In eight of 32 biopsies colonies of coccoid bacteria or Malassezia pachydermatis-like yeasts were observed. IgG-bearing plasma cells were found in similar numbers in the inflammatory infiltrates of all types of histological lesion, and were invariably more numerous than IgM or IgA plasma cells. The IgG plasma cells were largely IgG4 in lesions of perifolliculitis, but consisted of a mixture of IgG2 and IgG4 where folliculitis or furunculosis was present. CD3+T lymphocytes were prominent within the interface infiltrates of follicular epithelium and also within the lesions of furunculosis. Dermal inflammatory cells and epidermal Langerhans cells expressing MHC Class II were observed in similar number in all types of lesion. The study demonstrated an active local cutaneous immune response in canine demodicosis, which increased as the dermal pathology progressed from perifolliculitis to furunculosis.
The Dalmatian dog is susceptible to congenital deafness which is thought to be inherited. The condition cannot be treated or cured, but controlled breeding could prevent or minimize the occurrence. An understanding of the quantitative relationship between the relevant attributes (sex, colour etc.) and the probability of deafness is likely to be of assistance in implementing any breeding programme to eliminate the condition. Most reported studies on Dalmatians have ignored the hearing status of close parental relatives, and none has taken into account the likely positive correlations in dogs from same litters. A composite database, obtained by merging deafness data on 1234 tested Dalmatians with Kennel Club pedigree data on 22,873 Dalmatians in the United Kingdom, has enabled us to include the hearing status of parental relatives and litter effects in our analysis. Contingency tables and ordinary logistic regression were used to obtain preliminary results which could be compared with the findings from other studies based on similar analyses. Further logistic modelling included an additional random effects term for the effect of litters to which the dogs belonged. The preliminary analysis showed that the prevalence of overall deafness in the tested Dalmatians was 18.4%, of which 13.1% were unilaterally deaf, and 5.3% were bilaterally deaf. There was no association between deafness and either testing location or coat colour but prevalence was strongly associated with parental hearing status. In Dalmatians from normal dams the prevalence (15.6%) was significantly lower than in those from untested dams (21.9%). If the parents were both normal or both untested, these figures were 15.3 and 23.6%, respectively, and significantly different. There was a significant gender effect, the prevalence being significantly higher in females (21.1%) than in males (15.5%), and this was seen in all subsets of data partitioned by parental hearing status, by locations, and by dominant coat colours. The use of generalized modelling, which included the random litter effects yielded point estimates of the prevalence of deafness which were smaller, but with wider confidence limits. Breeding from only tested and proven normal dams and sires is therefore recommended, and should reduce overall deafness to below 15% and bilateral deafness to below 4%.
Skin biopsies from 13 Shar Peis showing signs of cutaneous mucinosis and 13 control dogs of different breeds with no clinical or histological evidence of skin disease were examined. One section of each tissue sample was stained with haematoxylin and eosin, and another with toluidine blue to demonstrate the sulphated acid glycosaminoglycans in mast cell (MC) granules. To investigate the MC subtypes involved, the tryptase and chymase content of mast cells was evaluated by a double enzyme‐immunohistochemical staining technique. Regardless of the staining technique, a significantly lower mast cell density in the skin of Shar Peis was demonstrated. In the dermis of control dogs, we detected a median mast cell density of 31.2 MC/mm ² using the toluidine blue staining method and 27.5 MC/mm ² using the double labelling technique. In Shar Peis only 9.1 MC/mm ² were found by toluidine blue staining ( P = 0.001) and 14.8 MC/mm ² by the double labelling method ( P = 0.0387). The percentile distribution of mast cell subtypes was also significantly different in Shar Peis as compared to control dogs. Whereas in the dermis of control dogs the predominant mast cell subtype was the tryptase and chymase containing MC (TC‐MC) (60.4 %), in Shar Pei skin the only chymase containing MC (C‐MC) predominated (62.2 %) and the percentage of TC‐MC was significantly lower (32.9 % P = 0.0016). The percentage of only tryptase containing MC (T‐MC) (4.7 %) was higher in Shar Peis compared to control dogs (1.9 % P = 0.0178). The data obtained indicate a possible involvement of mast cell subtypes in the pathogene