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The predictive performance of the breed specific models (A) boxplots show the distributions of the estimated probability of being BOAS-affected. The dotted line at 50% of the probability represents the raw predictive cut-off. For pugs and French bulldogs, the cut-off values can be adjusted to improve the specificity of the models; (B) receiver operating characteristic (ROC) curves show the predictive performance of the breed specific models. Area under the curve (AUC) was computed with its 95% confidence interval in the bracket.
Source publication
Extremely brachycephalic, or short-muzzled, dog breeds such as pugs, French bulldogs, and bulldogs are prone to the conformation-related respiratory disorder—brachycephalic obstructive airway syndrome (BOAS). Affected dogs present with a wide range of clinical signs from snoring and exercise intolerance, to life-threatening events such as syncope....
Citations
... In this patient, the oropharyngeal dermoid cyst was believed to be physically obstructing the respiratory tract, leading to the clinical signs present, such as syncope and cardiac arrhythmias [10]. Physical obstruction of the oral cavity is likely attributed to the severe upper airway disease, secondarily causing vagallymediated sinus pauses and subsequent syncopal episodes; this has been documented in brachycephalic breeds [11]. In this case, however, the patient's syncopal episodes resolved with the Two-dimensional (2D) transverse plane CT images of frothy material within nasal choanae, bilaterally (blue rectangle). ...
... This connection between nasal stenosis and BOAS illustrates how anatomical features inherited through specific breeding practices can predispose certain breeds to complex and challenging conditions, emphasizing the need for awareness and careful considerations in the management and breeding of these popular breeds 2,4 . ...
... Each image was carefully assessed to determine the degree of stenosis of the nostrils, following criteria established by experts in the field. The images were then annotated using the RoboFlow tool, and according to Liu et al. 2 four classes were classified as open (i.e., non stenotic) (A), mild stenosis (B), moderate stenosis (C) and severe stenosis (D), as can be seen in Table 4. It is important to note that each image contains two nostrils, which are classified individually. ...
Nasal stenosis in bulldogs significantly impacts their quality of life, making early diagnosis crucial for effective treatment. This study developed an automated deep learning model to classify the severity of nasal stenosis using 1020 images of bulldog nostrils, including both real and AI-generated samples. Five neural network architectures were tested across three experiments, with DenseNet201 achieving the highest median F-score of 54.04%. The model’s performance was directly compared to trained human evaluators specializing in veterinary anatomy, achieving comparable levels of accuracy and reliability. These results demonstrate the potential of advanced neural networks to match human-level performance in diagnosis, paving the way for enhanced treatment planning and overall animal welfare.
... 'Pedigree Dogs Exposed') have led to a shockwave among the general public and the number of bans imposed on certain cat and dog breeds in various countries is increasing [1]. The origin of these claims and legal bans are linked to the observations that both dogs and cats suffer from a variety of genetic diseases, like canine brachycephalic obstructive airway syndrome and osteochondrodysplasia in the Scottish Fold, at high frequencies, with some of them associated with breed standards [2][3][4][5]. ...
Background
In human medicine, questions regarding heritable disorders are dealt with by clinical geneticists and genetic counselors and both the field, their roles and the tools they use are well-defined. Even though the prevalence of diseases is far higher and scientific literature agrees on expectations towards an increased importance, this does not seem to be the case in veterinary medicine. While we hypothesize that there will be an overlap, some characteristics uniquely linked to veterinary medicine might not be covered.
Methods
To investigate this in-depth and in an attempt to define the field, we compared the internationally accepted definitions and its subparts on genetic counseling in human medicine with what is found in veterinary literature and what was seen in cats and dogs presented at our dedicated small animals clinical genetics/genetic counseling clinic. The results were used in a stepwise analysis that lead to a set of three potential definitions (i.e. on what genetic counseling is, who provides it and which tools are used) that fullfill four criteria (i.e. definitions have to be clear/self-explanatory, minimally sufficient, complete and valid).
Results
The short version of the definition of genetic counseling in veterinary medicine is: "Genetic counseling is the process of helping animal owners and breeders understand – and adapt to – the medical, psychological, familial implications of genetic contributions to disease.” Genetic counseling in small animal practice is currently provided by veterinarians and the tools that are used, can be divided in five categories. The signalment of the patients revealed that both cats (30%) and dogs (70%) and various breeds, the two sexes (37% males, 63% females) and all age categories (puppy/kitten—senior) were represented. Furthermore, 73% of the patients were referred by or needed to be referred to other disciplines.
Conclusion
These definitions are derived from human and veterinary literature, and an evaluation based on patient data has demonstrated that these definitions meet all the criteria of a correct definition (i.e. clear, minimally sufficient, complete and valid). With these definitions and case descriptions, our aim is to contribute to the formal foundation of genetic counseling in veterinary medicine.
... These alterations may present in isolation or in combination, and in different degrees of morbidity [14,15,1,22]. As a result of the anatomical changes that obstruct the airways, clinical signs such as snoring, respiratory distress, exercise intolerance, rales, tachypnea, hyperthermia, dyspnea and cyanosis appear [13,12,20,23]. ...
... About 60% of veterinarians and owners do not know how to recognize the clinical signs of this disease, impairing early treatment. However, in recent years, there has been growing concern about the welfare of animals with this syndrome [17,16,20,24,22]. Physical examination, the patient's medical history, and an evaluation under general anesthesia are used for the diagnosis of BOAS. ...
An animal nose identification system could allow efficient monitoring of pets, and it can be used in applications such as identifying animal breeds or possible diseases and/or injuries. For that, a bulldog image dataset was build from French bulldogs. To carry out the validation through cross-validation, 10 folds (K-folds) were created. Afterward, five convolutional neural networks (CNN) were trained with our dataset to identify the nose: Faster R-CNN (Region-based CNN), SABL (Side-Aware Boundary Localization), RetinaNet (ResNet50+FPN), VFNet (VarifocalNet), and ATSS (Adaptive Training Sample Selection). Faster R-CNN, SABL, RetinaNet, VFNet and ATSS were used for training in the first phase, while ATSS, Faster R-CNN, ATSS and SABL in the second. The results showed that the ATSS network obtained the highest values of mAP and Accuracy in the first phase. Moreover, SABL network achieved the highest values
of mAP50, mAP75, Recall, F-Score and Accuracy at the end of the second phase.
... Depending on the cause, this may include correction of the nostrils, nasal vestibule and soft palate, laser-assisted turbinectomy, resection of everted laryngeal saccules and arytenoid lateralization (23). However, dogs with severe BOAS also have an increased risk of anesthesia (27,28). ...
... Signs of syncope or cyanosis (present or absent), nostril size (open or mild, moderate or severe stenosis), presence of stertor or stridor (present or absent) and auscultatory cardio-pulmonary sounds (normal or abnormal) of the study participants were determined. Based on these results, they were then categorized into the functional BOAS scoring system from 0 to 3 (28,29). Dogs with no BOAS (BOAS 0) or very mild BOAS (BOAS 1) were assigned to the control group. ...
... However, this could not be determined in this dog. With a BCS of 7/9, this dog's prognosis was found to be worse than that of a dog with a normal BCS which is consistent with studies by Liu et al. (28,52), which identified obesity as a significant BOAS risk factor. The mean BCS in this study's surgery group (6.4/9) was comparable to the control group (5.6/9). ...
Introduction
Brachycephalic obstructive airway syndrome (BOAS) significantly impacts the physical fitness of affected dogs. This study aimed to assess changes in physical fitness, as measured by vital signs and salivary cortisol and vasopressin concentrations, before and after BOAS surgery using a standardized fitness test.
Methods
A prospective clinical study was conducted on 35 brachycephalic dogs, including 13 Pugs, 21 French Bulldogs, and one English Bulldog. A preliminary examination included clinical anamnesis and a general examination. Physical fitness was evaluated using a submaximal treadmill test consisting of three 5-minute runs followed by a recovery phase. Vital signs were monitored throughout the test and saliva samples were taken before, immediately after and 15 min after the test. Eighteen animals underwent surgery due to moderate to severe BOAS symptoms, while 17 animals that were free of symptoms were assigned to the control group.
Results
One month post-OP (post-operatively), dogs that underwent BOAS surgery exhibited significant improvement in physical fitness based on vital signs. However, they remained significantly less fit than the control group. No statistically significant changes were observed in salivary cortisol or vasopressin concentrations before and after surgery.
Discussion
BOAS surgery reduces clinical symptoms and improves physical fitness, but affected dogs continue to exhibit substantial limitations. The consistency of cortisol and vasopressin levels across both groups reinforces the hypothesis of a stress-induced HPA-axis dysfunction, yet the limited number of evaluable samples and external influences suggest that salivary stress hormones alone may not reliably indicate surgical success. Future studies should incorporate additional biomarkers and clinical assessments to better understand the physiological impact of BOAS and its treatment.
... The rising popularity of brachycephalic dog breeds as companions is in part due to their paedomorphic features including a rounded wide skull, shortened rostrum and protruding eyes [1][2][3]. Pugs have become one of the most popular brachycephalic breeds in the last decade; they were one of the top three toy breeds registered in the past five years in the UK [4] and one of the top five most popular toy breeds registered in Australia [5]. Pugs are predisposed to more than 25 disorders in the broad groups of respiratory, neurological, ophthalmological, gastrointestinal and dermatological problems [2,3,6,7], with many problems related to their brachycephalic morphology. ...
... Pugs have become one of the most popular brachycephalic breeds in the last decade; they were one of the top three toy breeds registered in the past five years in the UK [4] and one of the top five most popular toy breeds registered in Australia [5]. Pugs are predisposed to more than 25 disorders in the broad groups of respiratory, neurological, ophthalmological, gastrointestinal and dermatological problems [2,3,6,7], with many problems related to their brachycephalic morphology. Pugs are particularly at risk of brachycephalic obstructive airway syndrome (BOAS) and corneal disorders even among brachycephalic breeds [3,8,9] with international calls for action to reduce the suffering caused by their prevalence. ...
... Pugs are predisposed to more than 25 disorders in the broad groups of respiratory, neurological, ophthalmological, gastrointestinal and dermatological problems [2,3,6,7], with many problems related to their brachycephalic morphology. Pugs are particularly at risk of brachycephalic obstructive airway syndrome (BOAS) and corneal disorders even among brachycephalic breeds [3,8,9] with international calls for action to reduce the suffering caused by their prevalence. The three most prevalent disorders in pugs in the UK in 2013 were overweight/obesity, corneal disorder and otitis externa [8]; however, while these conditions have been identified to be common in the breed, their prevalence has not been reported in Australia. ...
Pugs are highly predisposed to corneal disorders, such as brachycephalic ocular syndrome (BOS), due to their disproportionate skull, reduced corneal sensitivity and eyelid anomalies such as distichiasis, entropion and lagophthalmos. The risk of corneal disorders which cause significant suffering is substantial, prompting calls for international efforts to reduce their prevalence. While these debilitating conditions are also likely to be common in pugs in Australia, their prevalence and risk factors have not been reported. The anonymised electronic patient records (EPRs) of 1318 pugs attending 139 primary care veterinary clinics participating in VetCompass Australia (VCA) in 2017 were used to investigate the prevalence of ophthalmological pathologies and associated demographic risk factors. Pugs were diagnosed with overweight/obesity (prevalence: 20.2%, 95% confidence interval {CI}: 18.1–22.4) ophthalmological abnormalities (14.5%, 95% CI: 12.6–16.3), particularly corneal disorders (12.4%, 95% CI: 12–15.7), and other conditions. The most prevalent ophthalmological disorders were corneal ulcers (5.5%, 95% CI: 4.4–6.9), corneal pigmentation (3.6%, 95% CI: 2.8–4.8) and keratoconjunctivitis sicca (KCS) (3.3%, 95% CI: 2.5–4.5). The risk of all corneal disorders increased with age (odds ratio 1.11, 95% CI: 1.07–1.15), and corneal pigmentation, KCS and keratitis were more prevalent in older pugs (a median age of 7.6 years or older), while entropion, neovascularisation and ulcerative keratitis affected younger dogs (a median age of 3 years or under). The underlying BOS conformation defects, exophthalmos, lagophthalmos and distichiasis, and early signs of corneal damage should be identified through detailed examinations during primary care veterinary visits, and affected pugs should be removed from the breeding population and treated to reduce the severity and duration of their suffering.
... Dentro os sinais clínicos envolvidos, dispneia e tosse crônica são os mais relatados (Clarke, 2018;Warwick et al., 2021). Comorbidades relacionadas envolvem bronquites crônicas, endocardiose de mitral e obesidade (Liu et al., 2017;Reinero & Masseau, 2021). ...
Stenosis/collapse of the bronchi is a condition of luminal narrowing, often associated with obstructive syndromes in brachycephalic dogs, with the pug being one of the most predisposed breeds. The most common clinical signs include dyspnea and chronic cough. Diagnosis can be achieved through bronchoscopy, radiography, and computed tomography. The described patient presented clinical signs such as nasal discharge and dyspnea. This study reports a case of stenosis/collapse of the left main bronchus, diagnosed using a combination of imaging techniques, radiography, computed tomography, highlighting the importance of a detailed evaluation of direct and indirect findings from theses imaging modalities to reach this diagnosis
... Based on the level of fulfilment of the criteria, a traffic light system is used to indicate whether the animals can be used for breeding (green), can be accepted during a transition period (yellow), or are unacceptable (red). However, very few individuals of some breeds can meet this yellow or green criterion (Packer et al. 2015;Liu et al. 2017) so in practice this amounts to a ban on breeding a number of flat-faced dog breeds. The legal actions in The Netherlands originally focused on breeders associated with the national kennel club, neglecting the fact that many individuals from the breeds in question are imported from outside the country in which the legislation had no effect. ...
The modern idea of purebred dogs has come under increasing critical scrutiny over recent decades. In light of this critical focus and other developments in society, some new trends in how companion dogs are bred and acquired have emerged. This means a diminishing influence from traditional kennel clubs with more dogs being sold without a pedigree, stricter legal restrictions on dog breeding, growing popularity of deliberate crosses of established breeds (i.e. so-called designer breeds) and growing hype around the benefits of mixed-breed dogs. We give an overview of these trends and discuss to what extent they will serve to promote dogs that are innately healthy, have good welfare and function well in their various roles in today’s world. We argue that newly invented designer breeds and mixed breeds also have worrying health and behavioural problems, and that the predictability of purebred dogs with respect to body size, basic behaviours, known need for grooming, disorder profiles and other attributes may well offer some benefits for a satisfying human-dog relationship seen from both sides. The optimal future seems to lie in the middle ground, where the future organised dog world (i.e. kennel and breed clubs or their successor organisations) will need to re-open the breed registries, remove wording from breed standards that currently promotes extreme conformation, support selection against disease-predisposing genotypes and phenotypes and refocus dog showing and breeding to promote health and appropriate behaviour.
... Until now, the methods used for diagnosing and grading BOAS are based on several anatomical or functional approaches. Anatomical approaches range from soft-tape and visual nostril assessments (17) to computer tomography (CT) (18,19) and endoscopy (19). While soft-tape measurements are non-invasive and easy to obtain, they suffer moderate to poor inter-rater reliability (17). ...
... Anatomical approaches range from soft-tape and visual nostril assessments (17) to computer tomography (CT) (18,19) and endoscopy (19). While soft-tape measurements are non-invasive and easy to obtain, they suffer moderate to poor inter-rater reliability (17). Among externally accessible anatomical parameters, stenotic nostrils have been one of the most robust predictors of BOAS severity across different breeds, including French Bulldogs (17). ...
... While soft-tape measurements are non-invasive and easy to obtain, they suffer moderate to poor inter-rater reliability (17). Among externally accessible anatomical parameters, stenotic nostrils have been one of the most robust predictors of BOAS severity across different breeds, including French Bulldogs (17). However, nostril assessment alone does not cover the full range of anatomic anomalies in brachycephalic dogs. ...
Brachycephalic breeds suffer from respiratory distress known as brachycephalic obstructive airway syndrome (BOAS) and the multiple comorbidities associated with it. Targeted breeding toward a more BOAS-free phenotype requires accurate and least invasive detection of BOAS severity grades that are accessible and accepted by the breeders and kennel clubs. This study aimed to compare the-outcome of morphometric anatomical examination with functional tests such as exercise tests and plethysmography for the detection of BOAS severity in a group of 84 French Bulldogs. In addition, we investigated the possibility of assessing the severity of BOAS using blood parameters that were found to vary between the brachycephalic and non-brachycephalic dogs in our previous study. We found the results of the trotting test to be most reliable compared to the outcome of respiratory performance assessment using plethysmography. Of all the candidate blood parameters tested, carboxyhemoglobin and oxyhemoglobin levels were the most predictive as on-side but not self-standing indicators of BOAS severity grade. Aggravation of BOAS manifestation was associated with mild stress erythropoiesis and oxidative stress. Based on our findings, we suggest continuing to use the trotting test as the method of choice for the selection of breeding dogs; in questionable cases, a temperature increase of more than 0.4°C indicates at least grade 2. Furthermore, co-oximetry could be used as an additional test to enable assignment to one of the two BOAS grades in dispute. Among the limitations of this study are the focus on one breed and the low number of animals with severe clinical signs of BOAS in the study cohort.
... 7,8 In dog breeds such as Pugs and Bulldogs obesity results in increased risk of brachycephalic obstructive airway syndrome (BOAS), with many clinical consequences. 9 In addition to overall body mass index (BMI), recent studies in humans and dogs have focused on the role of the size of the tongue and tongue fat volume in obese patients and the relationship of these measurements to upper respiratory tract (URT) obstructive disorders. [10][11][12][13] These studies found that obese apnoeic human patients had larger tongues with a higher tongue fat percentage than obese patients without OSA. ...
Background
Obesity has been associated with human obstructive sleep apnoea and canine brachycephalic obstructive airway syndrome. The effect of body condition score (BCS) on structures of the oropharynx, nasopharynx and upper airway of the horse has not been investigated.
Objectives
To investigate the effect of BCS on tongue measurements, soft palate angle and basihyoid depth in horses.
Study design
Retrospective, analytical, cross‐sectional.
Methods
Computed tomographic (CT) images of the head of 58 horses were assessed. DICOM viewing software was used to measure head length, basihyoid‐skin depth, soft palate angle (SPA), midline tongue area, dorsoventral height (DVH) of the tongue in two locations and head angle. BCS were assigned during CT examinations. Associations between measurements were tested and following initial calculations, further associations with tongue measurements as a ratio of head length were assessed.
Results
For initial measurements, 44 horses met the inclusion criteria. Addition of head length ratios to tongue measurements resulted in 24 of 44 horses meeting the inclusion criteria for the second set of calculations. Increased BCS led to an increased mean SPA (mean difference = 2.56; p = 0.02) and increased median basihyoid depth (mean difference = 0.246 cm; p = 0.006). Following adjustments made for the effect of head length on tongue measures, significant correlation was identified between SPA and tongue area (Spearman's r = 0.544; p = 0.007); SPA and DVH of the tongue at the level of the hard palate (Spearman's r = 0.562; p = 0.004) and SPA and DVH of the tongue at the lingual process of the basihyoid bone (Spearman's r = 0.690; p < 0.001). No significant correlation was identified between variables and sex.
Main limitations
The sample size was small and the effect of breed on measures was not studied. Measurements were acquired on a single sagittal CT plane. The investigator collecting CT measures was not blinded to BCS. All horses were sedated for the CT procedure which may have affected measures obtained.
Conclusions
Increased BCS increases SPA and basihyoid bone depth. Increases in tongue size measurements increase SPA. Results from this study warrant further investigation into the clinical significance of the effects of BCS on the upper airways of the horse.
