Conformational risk factors of brachycephalic obstructive airway syndrome (BOAS) in pugs, French bulldogs, and bulldogs

Comparison of remote and in-person respiratory function grading of brachycephalic dogs

OBJECTIVE

To compare the reliability of respiratory function grading (RFG) scores assigned in-person and remotely via video and electronic stethoscope recordings, evaluated by novice and expert graders.

STUDY DESIGN

Prospective study.

SAMPLE POPULATION

Fifty-seven brachycephalic dogs.

METHODS

Dogs were evaluated in person by expert graders and RFG scores were assigned. Audio and video recordings were made during the in-person evaluations. Four expert and four novice graders evaluated the recordings and assigned an RFG score to each dog. Agreement between in-person and remote RFG scores was assessed using Cohen's kappa statistic. Interobserver reliability was assessed using Fleiss' kappa statistic.

RESULTS

The median RFG score from the in-person assessment was 1 (range, 0-3). Distribution of RFG scores included 12 grade 0 scores, 19 grade 1 scores, 25 grade 2 scores, and 1 grade 3 score. The raw percentage agreements between remote and in-person scores were 68.4%, 59.6%, 64.9%, and 61.4% for the four experts, and 52.6%, 64.9%, 50.9%, and 42.1% for the four novices. Reliability between remote and in-person RFG scores was poor to moderate both for the experts (Cohen's kappa: .48, .37, .46, .41) and novices (Cohen's kappa: .28, .47, .28, .21). Interobserver reliability was moderate among the experts (Fleiss' kappa: .59) and poor among the novices (Fleiss' kappa: .39).

CONCLUSION

Remote RFG scores had poor to moderate interassessment and interobserver reliability. Novice evaluators performed worse than experts for remote or in-person RFG evaluations.

CLINICAL SIGNIFICANCE

Remote RFG, as measured in this study, is not reliable for assigning RFG scores. Modifications could be made to remote evaluation to improve reliability. Based upon the performance of novice evaluators, training of evaluators is justified.

Evaluation of measurements for tracheal hypoplasia in French bulldogs

Tracheal narrowing may increase airflow resistance, resulting in clinical manifestations associated with brachycephalic obstructive airway syndrome (BOAS). When diagnosing tracheal hypoplasia, established values are based on measurements established for English bulldogs or non-specific "bulldog" breeds. The objective of this study was to investigate tracheal diameter ratios in French bulldogs to gain a better understanding of what would constitute tracheal hypoplasia in this breed. A retrospective observational analysis was conducted to measure the right lateral thoracic radiographs of 139 French bulldogs to investigate tracheal diameter ratios. Pulmonary disease was observed in 55/139 dogs. The mean TD:Ti for healthy French bulldogs was 0.15 (±0.02), and the mean TD:ML was 0.32 (±0.07). 44/84 dogs had a TD:Ti < 0.15 (±0.02), and 37/65 dogs had a TD:ML < 0.32 (±0.07). At least one thoracic vertebral anomaly was observed in 131/139 of evaluated French bulldogs, and sternal malformations were observed in 42/139 dogs. TD:ML showed an excellent interclass correlation between observers (ICCinter 0.9562). The listed covariables were compared for statistical significance when measuring relative tracheal ratios, and none were found. There was a statistically significant relationship between TD:Ti and sex. An objective value for tracheal hypoplasia in French bulldogs has previously not been established. The mean TD:Ti described for French bulldogs in this study is higher than that previously described in other "bulldog" populations. The mean TD:ML is similar to previously reported for non-brachycephalic and non-bulldog brachycephalic small breed dogs. The correlative relationship between TD:Ti and TD:ML was statistically significant but weak.

Salivary cortisol measurements in brachycephalic dog breeds as part of a standardized stress test

Introduction

Brachycephalic obstructive airway syndrome (BOAS) is a common condition in brachycephalic dogs, with Pugs (PG) and French Bulldogs (FB) appearing to be particularly typically affected. Objective and easy-to-perform tests are necessary to detect the disease at an early stage and to exclude dogs affected by BOAS from breeding.

Methods

The present study investigated the extent to which vital signs and salivary cortisol concentrations can be used to distinguish between healthy and BOAS-affected dogs in a standardized fitness test. A total of 57 PG, 56 FB and 27 meso- and dolichocephalic dogs were studied as control group (CG). In addition to vital signs, salivary cortisol concentrations were measured before and after the exercise test.

Results

It emerged that non-brachycephalic dogs showed a higher fitness level than brachycephalic dogs. The PG recovered significantly slower than the FB after the exercise test. In unaffected PG, cortisol levels rose significantly after the test and then fell again, in unaffected FB they fell significantly during the test. Unexpectedly, cortisol levels remained constant in BOAS affected dogs of both breeds.

Discussion

A possible explanation could be a disturbance of the pituitary-hypothalamic-adrenal axis, which could be due to the chronic stress of affected animals. This would have to be clarified in further studies. In conclusion, a submaximal fitness test may be a useful method to identify dogs suffering from BOAS as it is imperative to prevent the breeding and reproduction of affected dogs.

Evaluation of brachycephalic obstructive airway syndrome breeding test results in Finland from 2017 to 2022

BACKGROUND

Brachycephalic obstructive airway syndrome (BOAS), observed in many flat-faced dog breeds, is one of the most urgent welfare problems in pedigree dogs. Various breeding schemes against BOAS have been implemented in many countries during recent years, but their impact on breed health remains unknown. The BOAS breeding test, used by the Finnish Kennel Club (FKC), includes an exercise component with a recovery assessment, BOAS grading by a veterinarian that evaluates upper respiratory signs before and after exercise, and a nostril stenosis assessment. The aim of our study was to evaluate BOAS breeding test results and estimate the heritability of the BOAS grade using parent-offspring regression from FKC data collected during 2017-2022.

RESULTS

The majority (80%) of dogs (n = 957) participating in FKC BOAS testing were English Bulldogs, French Bulldogs, and Pugs. In 2022, 89-100% of the litters from these three breeds registered with the FKC had at least one parent tested for BOAS. The proportion of dogs failing the exercise test was highest in English Bulldogs (11%), followed by French Bulldogs (4%) and Pugs (3%). In these three breeds, moderate to severe BOAS signs were reported in 28%, 22% and 30% of dogs, respectively. The proportion of moderate to severe nostril stenosis was highest (71%) in Pugs, followed by French Bulldogs (55%), and English Bulldogs (40%). Estimates of heritability for BOAS grade were separately calculated for these three breeds and for all dogs, and the estimates were moderate to high, ranging from 0.39 to 0.58.

CONCLUSIONS

The exercise test alone did not sufficiently identify dogs with moderate to severe BOAS signs. To better consider the complex nature of BOAS and breed differences, exercise tolerance, the severity of upper respiratory signs (BOAS grade) and nostril stenosis should all be assessed together in breeding animals. The heritability estimates for veterinary-assessed BOAS grade indicated that BOAS grade could be used in selective breeding to obtain less-affected offspring.

Retrospective evaluation of radiofrequency volumetric tissue reduction for hypertrophic turbinates in dogs with brachycephalic obstructive airway syndrome

OBJECTIVE

The objective of this study was to retrospectively assess the effect of Radiofrequency Volumetric Tissue Reduction (RFVTR) on hypertrophic turbinates and clinical outcome in brachycephalic dogs when included in multi-level surgery (MLS).

STUDY DESIGN

Clinical retrospective multicenter study.

ANIMALS

132 client-owned brachycephalic dogs.

METHODS

132 brachycephalic dogs with high-grade Brachycephalic Obstructive Airway Ayndrome (BOAS) and hypertrophic turbinates were treated with RFVTR as part of MLS of the upper airways. Intranasal obstruction was evaluated by computer tomography (CT) and antero-/retrograde rhinoscopy before and 6 months after RFVTR. The clinical records, the CT images and the rhinoscopy videos were reviewed and clinical evolution was evaluated using a standardized questionnaire. The data was scored semi-quantitatively.

RESULTS

In this study, 132 patients were included for a follow-up period of 120 weeks. RFVTR resulted in minor complications, including serous nasal discharge within the first postoperative week in all dogs, and intermittent nasal congestion between 3-8 weeks after treatment in 24.3% of the patients. Rhinoscopy and CT follow-ups were available for 33 patients. Six months after treatment intranasal airspace was increased (p = 0.002) and the presence and overall amount of mucosal contact points was reduced (p = 0.039).

CONCLUSION

MLS with RFVTR led to a significant reduction in turbinate volume at the 6-month follow-up examination and significant clinical improvement over a long-term period of 120 weeks. This suggests the viability of RFVTR as a turbinate-preserving treatment for intranasal obstruction in dogs with BOAS.

CLINICAL SIGNIFICANCE

RFVTR is a minimally invasive turbinoplasty technique for intranasal obstruction in dogs with BOAS and can be included in MLS without increasing complication rates.

Laser-Assisted Turbinectomy in Dogs

This article discusses the laser-assisted turbinectomy (LATE) procedure and indications for its performance in dogs suffering from brachycephalic obstructive airway syndrome (BOAS). The article summarizes landmark works that reported, for the first time, endoscopic-assisted identification and treatment of structures within the brachycephalic nose that contribute to intranasal obstruction and resistance to breathing, specifically hypertrophic and aberrant nasal turbinates. Brachycephaly is discussed in the context of how these aberrations form and how definitive treatments such as LATE and adjunctive treatments such as ala vestibuloplasty, folded flap palatoplasty, and others may ameliorate the negative effects and improve patient outcomes associated with aberrant intranasal conchal configurations.

Assessment of glial fibrillary acidic protein and anti-glial fibrillary acidic protein autoantibody concentrations and necrotising meningoencephalitis risk genotype in dogs with pug dog myelopathy

BACKGROUND

Pugs commonly present with thoracolumbar myelopathy, also known as pug dog myelopathy (PDM), which is clinically characterised by progressive signs involving the pelvic limbs, no apparent signs of pain and, often, incontinence. In addition to meningeal fibrosis and focal spinal cord destruction, histopathology has confirmed lymphohistiocytic infiltrates in the central nervous system (CNS) in a considerable number of pugs with PDM. Lymphohistiocytic CNS inflammation also characterises necrotising meningoencephalitis (NME) in pugs. This study aimed to investigate the potential contribution of an immunological aetiology to the development of PDM.

METHODS

The concentrations of glial fibrillary acidic protein (GFAP) in serum and CSF and of anti-GFAP autoantibodies in CSF were measured with an ELISA. In addition, a commercial test was used for genetic characterisation of the dog leukocyte antigen class II haplotype, which is associated with NME susceptibility.

RESULTS

This study included 87 dogs: 52 PDM pugs, 14 control pugs, four NME pugs and 17 dogs of breeds other than pugs that were investigated for neurological disease (neuro controls). Anti-GFAP autoantibodies were present in 15 of 19 (79%) of the PDM pugs tested versus six of 16 (38%) of the neuro controls tested (p = 0.018). All 18 PDM pugs evaluated had detectable CSF GFAP. Serum GFAP was detected in two of three (67%) of the NME pugs and in two of 11 (18%) of the control pugs but not in any of the 40 tested PDM pugs. Male pugs heterozygous for the NME risk haplotype had an earlier onset of clinical signs (70 months) compared to male pugs without the risk haplotype (78 months) (p = 0.036).

LIMITATIONS

The study was limited by the lack of healthy dogs of breeds other than pugs and the small numbers of control pugs and pugs with NME.

CONCLUSIONS

The high proportion of PDM pugs with anti-GFAP autoantibodies and high CSF GFAP concentrations provide support for a potential immunological contribution to the development of PDM.

Morphological comparative study of canine and feline diaphragms: Effect of bodyweight, body condition score, gender, age and breed

The canine diaphragm is a muscular and tendinous dome-like plate and is largely involved in digestive and respiratory functions. Very few studies compared morphology of the diaphragm between dogs and cats and no studies have investigated the effects of individual factors on this morphology. So the aim of this study was to (1) study the effects of individual factors on the morphology of the diaphragm and (2) to compare its morphology between cats and dogs. Surface measurements of 86 diaphragms were performed. The tendinous centre (TC), the lumbar part of the peripheral muscular (LP) and the sternal and costal parts of the peripheral muscular (SCPM) were measured. Measurement ratios (surface of anatomical part of the diaphragm/total surface of the diaphragm) were used for statistical analysis (TC%S, LP%S, SCPM%S). The SCPM%S are significantly lower, and the LP%S are significantly higher when bodyweight increases in dogs and cats. The TC%S are significantly lower when the body condition score of dogs increases. The SCPM%S are significantly higher, and therefore, the TC%S and LP%S lower in brachycephalic animals as opposed to mesocephalic animals. The TC%S are significantly higher in dogs than in cats and the SCPM%S are significantly higher in cats than in dogs. This study proposed a cartography of the diaphragm morphology in cats and dogs taking into account individual animal factors. Significant differences in the diaphragm morphology between cats and dogs and between mesocephalic and brachycephalic animals were found. Further studies are necessary to confirm these results and to investigate the consequences of these variations.

Risk factors for complicated perioperative recovery in dogs undergoing staphylectomy or folded flap palatoplasty: Seventy-six cases (2018-2022)

OBJECTIVE

To analyze risk factors for complicated perioperative recovery of dogs undergoing either staphylectomy or folded flap palatoplasty.

STUDY DESIGN

Retrospective study.

ANIMALS

Seventy-six client-owned dogs.

METHODS

Medical records of dogs that underwent either staphylectomy or folded flap palatoplasty were reviewed for signalment, brachycephalic risk (BRisk) score, history of gastrointestinal signs, laryngeal collapse grade, presence of preoperative aspiration pneumonia, intraoperative respiratory and cardiovascular complications, length of general anesthesia, number of corrected brachycephalic obstructive airway syndrome (BOAS) components, and gastrointestinal and respiratory postoperative complications. Complicated recovery was defined as requirement for prolonged oxygen treatment and/or tracheostomy or perioperative death. Penalized logistic regression was used to identify risk factors.

RESULTS

Seventy-six dogs were enrolled in the study. Multivariate penalized logistic regression identified four risk factors for complicated recovery. These include surgery type (p = .0002), age (p = .0113), laryngeal collapse grade >2 (p < .0001) and length of general anesthesia (p = .0051).

CONCLUSIONS

In this population, dogs that had staphylectomy, increasing age, laryngeal collapse grade >2 and increasing length of general anesthesia were at increased risk for perioperative complicated recovery.

CLINICAL SIGNIFICANCE

The results of this study identified risk factors for perioperative complicated recovery in dogs undergoing elongated soft palate correction and may assist in surgical planning and early prediction of complications.

Fur Cortisol in French Bulldogs with Different Manifestations of Brachycephalic Obstructive Airway Syndrome

In the present study, 33 French bulldogs with varying degrees of brachycephalic obstructive airway syndrome (BOAS) were evaluated for various parameters to provide evidence of chronic stress in the dogs. For this purpose, an owner interview, a clinical examination, and cortisol concentrations in the fur of the dogs were collected. The median cortisol concentration in the fur of the dogs suffering from BOAS (n = 19) was 0.99 pg/mg (range 0.63-66.18), while that of the control group (n = 14) was 1.13 pg/mg (range 0.3-43.45). However, the statistical analysis did not reveal a statistically significant difference; therefore, it is not possible to distinguish between dogs clinically affected with BOAS and those without clinically relevant signs of the disease. There was no statistically significant difference between the age of the animals and the fur cortisol. None of the owners in the examination and control groups indicated that their dog was suffering from chronic stress which shows that the disease is easily underestimated and remains common. Thus, a thorough clinical examination by an experienced veterinarian remains the gold standard in order to diagnose BOAS.

Awareness, experiences, and opinions by owners, breeders, show judges, and veterinarians on canine Brachycephalic Obstructive Airway Syndrome (BOAS)

BACKGROUND

Exaggerated brachycephalic features have been highlighted over the last decade by their profound effect on the health and welfare of the affected dogs. The term brachycephalic obstructive airway syndrome (BOAS) was launched in the early 2000s and has received worldwide attention and awareness. At the same time, the popularity of brachycephalic dogs increased. This study aimed to reveal the awareness and experiences of health issues related to the physical appearance of brachycephalic breeds and compare perceptions and opinions on how to counteract these issues by various stakeholders (dog owners, veterinarians, dog breeders, and show judges) by performing an online survey.

RESULTS

Altogether, 1602 owners, 1551 breeders, 118 show judges, and 557 veterinarians participated. Awareness and experiences of conformation-related health issues were common among all stakeholder groups. Most participants agreed fully or partly that health issues related to conformity threaten the health of brachycephalic breeds; that the measures taken so far are positive; and that guidelines on the appearance of a dog should be based on knowledge regarding health issues related to physical appearance. A disagreement was noted on further measures to be taken and the importance of adhering to a breed standard.

CONCLUSIONS

All stakeholders were aware of health issues related to the appearance of brachycephalic dogs, but had variable personal experiences of these issues. Most participants agreed fully or partly that health issues related to conformity threaten the health of brachycephalic breeds, and that attention to these issues and measures taken so far are positive. However, there is a disagreement on further actions to be taken and the importance of adhering to a breed standard. These findings could be used to understand and bridge the gap in opinions between stakeholders and to refine methods to influence the health of dogs with exaggerated brachycephalic features.

Evaluation of the addition of adrenaline in a bilateral maxillary nerve block to reduce hemorrhage in dogs undergoing sharp staphylectomy for brachycephalic obstructive airway syndrome. A prospective, randomized study

OBJECTIVE

To assess the use of adrenaline (0.00198%) in a bilateral maxillary nerve block to reduce intraoperative hemorrhage in dogs undergoing staphylectomy for the treatment of brachycephalic obstructive airway syndrome (BOAS).

STUDY DESIGN

Prospective, randomized, double-blinded controlled study.

SAMPLE POPULATION

A total of 32 client owned, clinically affected dogs undergoing a cut and sew sharp staphylectomy for treatment of BOAS. A total of 16 dogs randomly assigned to adrenaline (A) group and 16 to no-adrenaline (NA) group.

METHODS

A bilateral maxillary nerve block was performed in all dogs prior to staphylectomy using lidocaine alone (group NA) or a combination of lidocaine and adrenaline (group A). Total hemorrhage was measured by weighing cotton-tipped applicators and swabs used on precision scales. In addition, a semi-quantitative hemorrhage score (1-5) was determined. Dogs were monitored for intraoperative hemodynamic stability during the procedure.

RESULTS

Total hemorrhage was significantly (p = .013) lower in group A compared with group NA. The median semi-quantitative hemorrhage score was significantly lower for group A (p = .029) compared with group NA. No significant adverse effects were noted due to adrenaline usage.

CONCLUSION

This study demonstrated that the use of adrenaline in a bilateral maxillary nerve block results in significantly lower intraoperative hemorrhage during cut and sew sharp staphylectomy and appeared safe to use.

CLINICAL SIGNIFICANCE

Potential clinical advantages include improved visualization, prevention of unnecessary blood loss and reduction in risk of blood aspiration.

Respiratory compromise in French bulldogs presented with intervertebral disc extrusion

BACKGROUND

French bulldogs hospitalised for the management of intervertebral disc extrusion (IVDE) are frequently affected by respiratory compromise, typically brachycephalic-associated upper respiratory obstruction and/or aspiration events. We evaluated the occurrence of such respiratory compromise events in French bulldogs presented to two referral hospitals.

METHODS

Clinical data for French bulldogs diagnosed with IVDE were retrospectively collated, including severity of neurological deficits, neuroanatomical localisation, diagnosis, details of respiratory compromise, treatment and outcome.

RESULTS

A total of 306 dogs diagnosed with IVDE were included. Sixty dogs (19.6%) experienced respiratory compromise, of which 31 dogs (10.1%) progressed to cyanosis, collapse or respiratory arrest.

LIMITATIONS

The study was limited by its retrospective nature. Furthermore, the duration of hospitalisation was not evaluated and the decision for euthanasia was often multifactorial.

CONCLUSION

One in five French bulldogs presented with IVDE experienced respiratory compromise. The detrimental welfare effects of this warrant further discussion.

BrachySound: machine learning based assessment of respiratory sounds in dogs

The early and accurate diagnosis of brachycephalic obstructive airway syndrome (BOAS) in dogs is pivotal for effective treatment and enhanced canine well-being. Owners often do underestimate the severity of BOAS in their dogs. In addition, traditional diagnostic methods, which include pharyngolaryngeal auscultation, are often compromised by subjectivity, are time-intensive and depend on the veterinary surgeon's experience. Hence, new fast, reliable assessment methods for BOAS are required. The aim of the current study was to use machine learning techniques to bridge this scientific gap. In this study, machine learning models were employed to objectively analyze 366 audio samples from 69 Pugs and 79 other brachycephalic breeds, recorded with an electronic stethoscope during a 15-min standardized exercise test. In classifying the BOAS test results as to whether the dog is affected or not, our models achieved a peak accuracy of 0.85, using subsets from the Pugs dataset. For predictions of the BOAS results from recordings at rest in Pugs and various brachycephalic breeds, accuracies of 0.68 and 0.65 were observed, respectively. Notably, the detection of laryngeal sounds achieved an F1 score of 0.80. These results highlight the potential of machine learning models to significantly streamline the examination process, offering a more objective assessment than traditional methods. This research indicates a turning point towards a data-driven, objective, and efficient approach in canine health assessment, fostering standardized and objective BOAS diagnostics.

Lifetime prevalence of owner-reported medical conditions in the 25 most common dog breeds in the Dog Aging Project pack

Introduction

Large scale data on the prevalence of diverse medical conditions among dog breeds in the United States are sparse. This cross-sectional study sought to estimate the lifetime prevalence of medical conditions among US dogs and to determine whether purebred dogs have higher lifetime prevalence of specific medical conditions compared to mixed-breed dogs.

Methods

Using owner-reported survey data collected through the Dog Aging Project (DAP) Health and Life Experience Survey for 27,541 companion dogs, we identified the 10 most commonly reported medical conditions in each of the 25 most common dog breeds within the DAP cohort. Lifetime prevalence estimates of these medical conditions were compared between mixed-breed and purebred populations. The frequency of dogs for whom no medical conditions were reported was also assessed within each breed and the overall mixed-breed and purebred populations.

Results

A total of 53 medical conditions comprised the top 10 conditions for the 25 most popular breeds. The number of dogs for whom no medical conditions were reported was significantly different (p = 0.002) between purebred (22.3%) and mixed-breed dogs (20.7%). The medical conditions most frequently reported within the top 10 conditions across breeds were dental calculus (in 24 out of 25 breeds), dog bite (23/25), extracted teeth (21/25), osteoarthritis (15/25), and Giardia (15/25).

Discussion

Purebred dogs in the DAP did not show higher lifetime prevalence of medical conditions compared to mixed-breed dogs, and a higher proportion of purebred dogs than mixed-breed dogs had no owner-reported medical conditions. Individual breeds may still show higher lifetime prevalence for specific conditions.

Evaluation of the Submaximal Treadmill-Based Fitness Test in Six Brachycephalic Breeds-A Follow-Up Study

Brachycephalic obstructive airway syndrome (BOAS) in dogs challenges veterinary surgeons both with a complex clinical picture as well as wide-ranging ways to diagnose the disease, often not easily implemented nor standardised in clinical practice. The assessment of a combination of exercise testing, the occurrence of breathing noises, recovery time, and respiratory effort proved to be an appropriate method to identify Pugs with BOAS. The purpose of this study was to apply an established standardised, submaximal, treadmill-based fitness test for Pugs to other brachycephalic dog breeds. A total of 79 participants, belonging to 6 different brachycephalic breeds, trotted 15 min with an individual comfort speed of 3-7 km/h on a treadmill. Additionally, functional BOAS grading based on respiratory clinical signs before and after exercise was applied. The test was passed if the dogs presented with a BOAS grade of 0 or 1 and their vital parameters recovered to baseline within 15 min after exercise. A total of 68% showed a BOAS grade of 0 or 1 and passed the fitness test. Of the failed participants, 65% failed due to BOAS affectedness, 9% were categorised as not affected by BOAS and failed due to not passing the fitness test only, and 26% showed both failure criteria. The fitness test can be a useful method to identify BOAS-affected dogs in other brachycephalic breeds and to diagnose BOAS in dogs that only show clinical signs under exercise.

A novel surgical approach for feline stenotic nares: Bilateral wedge resection of the dorsal lateral nasal cartilage in seven cases

OBJECTIVE

Surgical correction of stenotic nares, one component of brachycephalic obstructive airway syndrome (BOAS), is not referenced as often in cats as it is in dogs. Similar to dogs, stenotic nares emerge as a significant contributor in the development of BOAS in cats. In this study, we propose that stenotic nares in brachycephalic cats arise from an elongated dorsal lateral nasal cartilage. The aim of this paper is to illustrate a novel surgical technique to alleviate stenosis-associated clinical signs by performing full-thickness bilateral wedge resection of the excessive cartilage.

ANIMALS

Seven cats that underwent rhinoplasty with full-thickness bilateral wedge resection along the dorsal lateral nasal cartilage between 2019 and 2022 at Pan-Asia Veterinary Clinic in Taipei, Taiwan.

METHODS

Clinical data of all cats included in the study were retrospectively reviewed. Surgical procedures were recorded. A full-thickness bilateral wedge resection was made along the dorsal lateral nasal cartilage adjacent to the non-hairy area. The full-thickness wedge resection was then apposed and closed, resulting in the abduction of the wing of the nostrils. Postoperative outcomes were evaluated according to follow-up sessions by the authors, and an owner survey was conducted at least 6 months post-surgery.

RESULTS

All cats included in this study had a favourable outcome with no complications reported following surgery. The degree of nostril stenosis was improved, and relapse of clinical signs was not reported. Overall, the quality of life of cats that underwent rhinoplasty was significantly improved.

CLINICAL RELEVANCE

The results support that the innovative procedure described in this study is highly promising and holds great potential in restoring quality of life and halting disease progression of cats with BOAS.

The effect of the surgical treatment of brachycephalic obstructive airway syndrome on the thermoregulatory response to exercise in French bulldogs: a pilot study

Introduction

Due to altered anatomy of the upper respiratory tract, brachycephalic dogs exhibit increased airway resistance and reduced surface area for evaporative heat loss, predisposing them to respiratory and thermoregulatory problems, a syndrome referred to as Brachycephalic Obstructive Airway Syndrome (BOAS). Compared to non-brachycephalic dogs, brachycephalic breeds are more susceptible to heat-related injuries even at low ambient temperatures and relatively low physical activity levels. Surgical treatment alleviates clinical signs, potentially improving dogs' thermoregulatory ability with BOAS. Our study aimed to investigate the thermoregulatory response in French bulldogs before and after the surgical correction of BOAS, respectively.

Methods

Thirteen dogs were exposed to dynamic exercise on a treadmill and the dynamics of their rectal temperature (RT) and heart rate (HR) was measured. The experiment was performed in two independent sessions, before and after the surgical treatment. The test consisted of two consecutive 5-min walks at a speed of 2.5 km/h, first at an inclination of 0% and the second at an inclination of 5%, and a 30-min recovery period. Rectal temperature and HR were measured before the start of the test (t0), at the end of the first (t1) and the second part (t2), and 15 min (t3) and 30 min (t4) in the recovery.

Results

A significant increase in RT and HR was observed during exercise and recovery compared to the resting values, implying that the exercise intensity was sufficient to challenge the thermoregulatory response. The increase of RT was significantly lower during both parts (t1: p  = 0.004; t2: p  <  0.001) of exercise after the surgical treatment than before the treatment. Although a trend of lower RT after recovery was observed compared to before the surgery, it did not reach statistical significance. Similarly to RT, the HR was significantly lower during exercise after the first (p  =  0.020) and the second part (p  =  0.011) of exercise after the surgery compared to before the surgery but did not reach significance in the recovery.

Conclusion

Surgical treatment of BOAS can improve thermoregulation during exercise in French bulldogs with BOAS.

The difference between two brachycephalic and one mesocephalic dog breeds' problem-solving performance suggests evidence for paedomorphism in behaviour

Despite serious health and longevity problems, small brachycephalic breeds are becoming increasingly popular among pet owners. Motivations for choosing short-nosed breeds have been extensively investigated in recent years; however, this issue has been addressed mainly by relying on owner reports, resulting in explanations of "cute looks", referring to the baby-schema phenomenon and "behaviour well suited for companionship". We aimed to compare the behaviour of two brachycephalic (English and French bulldogs) and one mesocephalic (Mudi) breed in a problem-solving context. The dogs were given the task of opening boxes containing food rewards. We investigated human-directed behaviour elements over success and latency (indicators of motivation and ability). We found that both English and French bulldogs were significantly less successful in solving the problem than mudis. Both brachycephalic breeds had longer opening latencies than the mesocephalic breed. Brachycephalic breeds oriented less at the problem box and more at humans present. In summary, the short-headed breeds were less successful but oriented much more toward humans than mesocephalic dogs. Owners might interpret these behaviours as "helplessness" and dependence. The results support the hypothesis that infant-like traits may be present not only in appearance but also in behaviour in brachycephalic breeds, eliciting caring behaviour in owners.

Comparison of habitual physical activity in French Bulldogs, Pugs and normocephalic dogs by accelerometry

Brachycephalic obstructive airway syndrome (BOAS) is a major welfare concern in flat-faced dog breeds. As BOAS causes respiratory difficulties and exercise intolerance, it can reduce dogs' daily quality of life (QOL). However, evaluation of QOL in dogs is difficult, and many owners perceive BOAS signs as 'normal' for the breed. Accelerometers that measure frequency, duration and intensity of activities can offer an objective way of evaluating dogs' daily activity and thereby deliver potential insights into QOL. The aim of this study was to assess habitual physical activity of 48 brachycephalic and 23 non-brachycephalic dogs using accelerometers. The accelerometers were used for one week and owners filled in a questionnaire regarding their dog's well-being and activities. Veterinary-assessed BOAS grading for brachycephalic dogs was determined. Compared with controls, more severely affected French Bulldogs and Pugs had significantly lower total activity counts and spent less time in high activity. In Pugs, mildly affected dogs were also less active, but age can be a contributing factor here, as older age decreased activity in Pugs and controls showed a wider age range. In French Bulldogs, those dogs with no or mild signs of BOAS did not differ from controls regarding their daily activity. In conclusion, accelerometers were easy to use for objective measurement of daily activity in bracycephalic dogs, although a degree of discomfort due to the collar was reported. Results showed that BOAS signs were associated with decreased habitual physical activity. These findings emphasise the importance of actions taken to reduce incidence of BOAS in brachycephalic breeds.

Differences in selected blood parameters between brachycephalic and non-brachycephalic dogs

Introduction

Cranial and upper-airway anatomy of short-nosed, flat-faced brachycephalic dogs predisposes them to brachycephalic obstructive airway syndrome (BOAS). Periodic apnoea increased inspiratory resistance, and an inability to thermoregulate effectively are characteristic of BOAS, but internationally accepted objective markers of BOAS severity are missing. The objective of this study was to compare the selected blood parameters between non-brachycephalic (NC) and brachycephalic (BC) dogs, exploring the possibility of developing a blood test for BOAS severity grading in the future.

Methods

We evaluated blood biochemistry, complete blood cell counts, red blood cell (RBC) indices, reticulocyte counts, a blood-born marker of intermittent hypoxia (glutathione, NO production), RBC hydration, deformability, and blood markers of metabolic changes and stress between BC (n = 18) and NC (meso- and dolichocephalic, n = 22) dogs.

Results

Reticulocyte counts and the abundance of middle-fluorescence immature reticulocytes were significantly (p < 0.05) higher in BC dogs compared to NC dogs. BC dogs had significantly more NO-derived NO2 - /NO3 - in plasma than NC dogs. RBCs of BC dogs were shedding significantly more membrane, as follows from the intensity of eosin maleimide staining, and had a significantly higher mean corpuscular hemoglobin concentration than NC dogs. Intracellular reduced glutathione content in RBCs of BC dogs was significantly lower, while plasma lactate was significantly higher in BC dogs compared to NC dogs. Plasma cholesterol and triglycerides were significantly lower, and cortisol was significantly higher in BC dogs compared to NC dogs. Eosinophil counts were significantly lower and the neutrophil-to-lymphocyte ratio was higher in BC dogs compared to NC dogs.

Discussion

Taken together, our findings suggest that the brachycephalic phenotype in dogs is associated with alterations at the level of blood cells and, systemically, with oxidation and metabolic changes. The parameters identified within this study should be further investigated for their potential as objective indicators for BOAS.

Comparative histological analysis of the alae nasi in French bulldogs with brachycephalic obstructive airway syndrome and unaffected non-brachycephalic dogs

BACKGROUND

Brachycephalic dogs are characterised by a short and flat nose. This cranial conformation is associated with brachycephalic obstructive airway syndrome, a respiratory syndrome primarily characterised by stenotic nares, a hyperplastic soft palate and a hypoplastic trachea, among other malformations, with secondary abnormalities resulting in upper airway obstruction METHODS: In this study, we aimed to characterise and compare the histological features of tissue samples harvested from the alae nasi of French bulldogs and non-brachycephalic dogs. Samples from the alae nasi of 11 French bulldogs and 13 non-brachycephalic dogs were collected. Four-μm-thick, paraffin-embedded sections were obtained from each tissue sample and mounted on glass slides, followed by staining with haematoxylin and eosin, periodic acid-Schiff and toluidine blue for histological examination.

RESULTS

The only variation observed between the samples obtained from French bulldogs and those obtained from non-brachycephalic dogs concerned the presence of cartilage in the specimens. Cartilage was absent in 10 of 11 French bulldogs but present in nine of 13 non-brachycephalic dogs; this difference was statistically significant (p < 0.05).

LIMITATIONS

The findings of this study need further validation in future prospective studies. It would be useful to examine the entire nostril wing, to include additional brachycephalic breeds, a larger number of subjects spanning a wider age range and degree of stenotic nares severity, a larger tissue sample, and a broadening of the control group to include dolichocephalic and mesaticephalic dogs.

CONCLUSION

This study found an absence of cartilage in French bulldog nare specimens compared to those from non-brachycephalic dogs. This absence of cartilage may contribute to brachycephalic obstructive airway syndrome, although histological examination of the entire wing of the nostrils is needed to confirm this hypothesis.

Dog breeds and conformations in the UK in 2019: VetCompass canine demography and some consequent welfare implications

INTRODUCTION

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.

METHODS

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.

RESULTS

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%).

CONCLUSIONS

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.

Description of a novel method for detection of sleep-disordered breathing in brachycephalic dogs

BACKGROUND

Sleep-disordered breathing (SDB), defined as any difficulty in breathing during sleep, occurs in brachycephalic dogs. Diagnostic methods for SDB in dogs require extensive equipment and laboratory assessment.

OBJECTIVES

To evaluate the usability of a portable neckband system for detection of SDB in dogs. We hypothesized that the neckband is a feasible method for evaluation of SDB and that brachycephaly predisposes to SDB.

ANIMALS

Twenty-four prospectively recruited client-owned dogs: 12 brachycephalic dogs and 12 control dogs of mesocephalic or dolicocephalic breeds.

METHODS

Prospective observational cross-sectional study with convenience sampling. Recording was done over 1 night at each dog's home. The primary outcome measure was the obstructive Respiratory Event Index (OREI), which summarized the rate of obstructive SDB events per hour. Additionally, usability, duration of recording, and snore percentage were documented.

RESULTS

Brachycephalic dogs had a significantly higher OREI value (Hodges-Lehmann estimator for median difference = 3.5, 95% confidence interval [CI] 2.2-6.8; P < .001) and snore percentage (Hodges-Lehmann estimator = 34.2, 95% CI 13.6-60.8; P < .001) than controls. A strong positive correlation between OREI and snore percentage was detected in all dogs (rs = .79, P < .001). The neckband system was easy to use.

CONCLUSIONS AND CLINICAL IMPORTANCE

Brachycephaly is associated with SDB. The neckband system is a feasible way of characterizing SDB in dogs.

Demography, common disorders and mortality of Boxer dogs under primary veterinary care in the UK

BACKGROUND

The Boxer is a popular dog breed with a distinctive appearance. However, the breed has been linked with several health conditions, some of which have been associated with its moderately brachycephalic conformation and its white colouration. Anonymised primary-care veterinary clinical records were explored to extract data on the demography, common disorders and mortality of Boxers in the UK in 2016.

RESULTS

The study population of 336,865 dogs included 3,219 (0.96%) Boxers, of which 10.71% were recorded as white. The mean adult bodyweight was 30.43 kg (SD 5.73 kg). Annual disorder counts did not differ statistically between the sexes or between white and non-white Boxers. The most prevalent fine-level precision disorders were otitis externa (n = 230, 7.15%), epulis (188, 5.84%), corneal ulceration (161, 5.00%) and periodontal disease (149, 4.63%). Of the 34 most common fine-level disorders, none differed in prevalence between white and non-white dogs. The most prevalent disorder groups were skin disorder (n = 571, 17.74%), neoplasia (457, 14.20%) and ear disorder (335, 10.41%). White Boxers had higher prevalence than non-white Boxers for two disorder groups: dental disorder and brain disorder. The median longevity of 346 Boxers that died during the study was 10.46 years (IQR 9.00-11.98, range 2.76-18.00). Median longevity did not differ statistically between the sexes or between white and non-white Boxers. The most common grouped causes of death were death - unrecorded cause (n = 73, 21.10%), neoplasia (43, 12.43%) and brain disorder (33, 9.54%).

CONCLUSIONS

There was minimal evidence of substantial health differences between white and non-white Boxers. Among the four most common disorders recorded in Boxers, two were typically common across all types of dogs (otitis externa and periodontal disease) while two suggested strong predispositions for the Boxer breed (epulis and corneal ulceration), showing the value of eliciting breed-specific disorder patterns for insights for potential health reforms. The overall longevity of Boxer dogs was consistent with other breeds of similar body size.

The epidemiology of upper respiratory tract disorders in a population of insured Swedish dogs (2011-2014), and its association to brachycephaly

Upper respiratory tract (URT) disorders are common in dogs but neither general nor breed-related epidemiological data are widely reported. This study´s aims were to describe the epidemiology of URT disorders in a Swedish population of dogs and to investigate whether brachycephalic breeds were overrepresented among high-risk breeds. A cohort of dogs insured by Agria Djurförsäkring in Sweden (2011-2014) was used to calculate overall and breed-specific incidence rate (IR), age at first URT diagnosis and relative risk (RR) for URT disorders. For breeds with high RR for URT disorders, co-morbidities throughout the dog's insurance period and age at death were investigated. The cohort included approximately 450,000 dogs. URT disorders had an overall IR of 50.56 (95% CI; 49.14-52.01) per 10,000 dog years at risk. Among 327 breeds, the English bulldog, Japanese chin, Pomeranian, Norwich terrier and pug had highest RR of URT disorders. Eight of 13 breeds with high RR for URT disorders were brachycephalic. The median age at first URT diagnosis was 6.00 years (interquartile range 2.59-9.78). French bulldogs with URT diagnoses had a significantly shorter life span (median = 3.61 years) than other breeds with URT diagnosis (median = 7.81 years). Dogs with high risk for URT disorders had more co-morbidities than average.

Echocardiographic analysis of dogs before and after surgical treatment of brachycephalic obstructive airway syndrome

Brachycephalic dogs with brachycephalic obstructive airway syndrome (BOAS) are a valuable animal model for obstructive sleep apnea (OSA) in humans. Clinical signs of upper airway obstruction improve after surgical treatment of BOAS, but the impact of surgery on morphology and function of the heart has not been studied. Therefore, we aimed to compare the echocardiographic variables of dogs before and after surgical treatment of BOAS. We included 18 client-owned dogs with BOAS (7 French Bulldogs, 6 Boston Terriers, and 5 Pugs) scheduled for surgical correction. We performed a complete echocardiographic examination before and 6 to 12 (median 9) months after surgery. Seven non-brachycephalic dogs were included in the control group. After surgery, BOAS patients had a significantly (p < 0.05) larger left atrium to aortic ratio (LA/Ao), left atrium in the long axis index, and thickness of the left ventricular posterior wall in diastole index. They also had a higher late diastolic annular velocity of the interventricular septum (Am) and increased global right ventricular strain and left ventricular global strain in the apical 4-chamber view, as well as a higher caudal vena cava collapsibility index (CVCCI). Before surgery, BOAS patients had a significantly lower CVCCI, Am, peak systolic annular velocity of the interventricular septum (Si), and early diastolic annular velocity of the interventricular septum (Ei) compared to non-brachycephalic dogs. After surgery, BOAS patients had a smaller right ventricular internal diameter at base index, right ventricular area in systole index, mitral annular plane systolic excursion index, and tricuspid annular plane systolic excursion index, as well as lower values of Am, Si, Ei, and late diastolic annular velocity of the interventricular septum, and a larger LA/Ao compared to non-brachycephalic dogs. Significant differences between BOAS patients and non-brachycephalic dogs indicate higher right heart pressures and decreased systolic and diastolic ventricular function in BOAS dogs, which is in accordance with the results of studies in OSA patients. In parallel with the marked clinical improvement, right heart pressures decreased, and right ventricular systolic and diastolic function improved after surgery.

Influence of feline brachycephaly on respiratory, gastrointestinal, sleep, and activity abnormalities

OBJECTIVE

To determine the influence of brachycephaly on respiratory, gastrointestinal, sleep, and activity-related parameters in cats.

STUDY DESIGN

Prospective questionnaire-based study.

ANIMALS

A total of 194 BC and 1003 non-BC cats.

METHODS

Owners completed an online questionnaire regarding respiratory, gastrointestinal, sleep, and activity-related parameters. Response options were scored, and individual scores summed to give a total clinical severity score for each cat.

RESULTS

Brachycephalic cats had more frequent snoring (odds ratio [OR] 6.89; 95% confidence interval [CI]: 5.06-9.41), sneezing (OR 6.52; CI: 4.75-8.98), nasal discharge (OR 8.26; 95% CI 5.77-11.85), coughing (OR 1.75; CI: 1.17-2.59), and dyspnea (OR 5.32; CI: 3.42-8.28); shorter activity before becoming dyspneic (OR 2.71; CI: 1.93-3.79), slower recovery from activity (OR 3.17; CI: 2.19-4.57), lower activity levels (OR 2.16; CI: 1.59-2.95), and increased respiratory noise (OR 6.68; CI: 4.71-9.52); and more hypersalivation (OR 2.50; CI: 1.47-4.16), halitosis (OR 1.40; CI: 1.00-1.95), and difficulty chewing (OR 5.19; CI: 3.65-7.38). Median clinical severity scores were higher for BC cats than non-BC cats (p < .0001).

CONCLUSIONS

Brachycephalic cats (BC) were at risk for respiratory, gastrointestinal, and activity-related symptoms compared to non-BC cats.

CLINICAL RELEVANCE

Some BC cats exhibit clinically relevant symptoms and behaviors as reported by owners. Medical or surgical interventions may improve these symptoms and warrant investigation.

Ala vestibuloplasty improves cardiopulmonary and activity-related parameters in brachycephalic cats

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.

Are Brachycephalic Dogs Really Cute? Evidence from Online Descriptions

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." Shortmuzzled, 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.

Echocardiographic parameters in French Bulldogs, Pugs and Boston Terriers with brachycephalic obstructive airways syndrome

BACKGROUND

In this prospective study, we hypothesized that dogs with signs of brachycephalic obstructive airway syndrome (BOAS) would show differences in left and right heart echocardiographic parameters compared with brachycephalic dogs without signs of BOAS and non-brachycephalic dogs.

RESULTS

We included 57 brachycephalic (30 French Bulldogs 15 Pugs, and 12 Boston Terriers) and 10 non-brachycephalic control dogs. Brachycephalic dogs had significantly higher ratios of the left atrium to aorta and mitral early wave velocity to early diastolic septal annular velocity; smaller left ventricular (LV) diastolic internal diameter index; and lower tricuspid annular plane systolic excursion index, late diastolic annular velocity of the LV free wall, peak systolic septal annular velocity, late diastolic septal annular velocitiy, and right ventricular global strain than non-brachycephalic dogs. French Bulldogs with signs of BOAS had a smaller diameter of the left atrium index and right ventricular systolic area index; higher caudal vena cava at inspiration index; and lower caudal vena cava collapsibility index, late diastolic annular velocity of the LV free wall, and peak systolic annular velocity of the interventricular septum than non-brachycephalic dogs.

CONCLUSIONS

The differences in echocardiographic parameters between brachycephalic and non-brachycephalic dogs, brachycephalic dogs with signs of BOAS and non-brachycephalic dogs, and brachycephalic dogs with and without signs of BOAS indicate higher right heart diastolic pressures affecting right heart function in brachycephalic dogs and those with signs of BOAS. Most changes in cardiac morphology and function can be attributed to anatomic changes in brachycephalic dogs alone and not to the symptomatic stage.

CT volumetric analysis permits comparison of tongue size and tongue fat in different canine brachycephalic and mesaticephalic breeds

While macroglossia is a newly accepted component of brachycephalic obstructive airway syndrome (BOAS) in dogs, macroglossia with increased tongue fat is a well-known cause for obstructive sleep apnea (OSA) in people, and targeted reduction procedures such as midline glossectomy are used to treat people with OSA. While midline glossectomy has been described in dogs, tissue contributions to macroglossia have not been characterized. The purpose of this retrospective, descriptive, case-control study was to describe and compare volumetric dimensions of the tongue and tongue fat in brachycephalic (BC) and mesaticephalic (MC) dogs using CT images. Data collected included head and neck CT images from 17 BC and 18 control MC dogs. Multiplanar reformatted and 3D reconstructed images were created using image segmentation and specialized visualization software to calculate volumetric dimensions of the total tongue, tongue fat, and tongue muscle. Rostral and caudal topographical distributions of fat were compared. Total tongue and tongue muscle volume (P < 0.0001) and tongue fat volume (P = 0.01) normalized to body weight (BW) were greater in BC dogs. More fat was localized in the caudal tongue in both groups (P < 0.04). In regression analysis, BC conformation and increased weight were significant predictors of increased tongue fat volume. As in people, increased tongue fat may contribute to macroglossia and sleep-disordered breathing in BC dogs. Use of CT volumetry to identify tongue fat deposits may permit targeted surgical reduction of tongue volume in BC dogs and contribute substantially to treatment of BOAS.

Thrombocytosis in brachycephalic dogs with brachycephalic obstructive airway syndrome

Brachycephalic dogs are prone to a conformation-related respiratory disorder known as brachycephalic obstructive airway syndrome (BOAS). Due to its systemic consequences, BOAS should be considered a systemic disease. The aim of the present study was to investigate platelet count (PLT), mean platelet volume (MPV), and plateletcrit (PCT) in patients with various grades of BOAS and non-brachycephalic dogs. The latter served as a control group. We included 106 patients with BOAS and 41 non-brachycephalic dogs. According to the severity of the disease, BOAS patients were classified into grade 1 (17 dogs), grade 2 (42 dogs), and grade 3 (47 dogs). Thrombocytosis was found in 46% (49/106) of all BOAS patients. High platelet mass was found in 62% (66/106) of all BOAS patients. We found significantly (P < 0.05) higher PLT, MPV, and PCT in BOAS patients of all grades compared to non-brachycephalic dogs. However, further studies are needed to clarify the role of PLT and platelet indices in BOAS and their relationship with inflammation and hypercoagulability.

Nasopharyngeal luminal change on cervical radiography in brachycephalic dogs without respiratory signs

This study aimed to prospectively assess nasopharyngeal luminal changes in brachycephalic dogs without respiratory signs using cervical radiography. Forty brachycephalic dogs without cardiopulmonary diseases were included. The nasopharyngeal luminal change was calculated on inspiratory and expiratory cervical lateral radiographs. The median nasopharyngeal luminal change was 21.6% (range, 0.3-85.6%). In five dogs, a nasopharyngeal luminal change of >50% was identified. There was no correlation between nasopharyngeal luminal changes and age, sex, body weight, or body condition score. These results suggest that brachycephalic dogs without cardiopulmonary diseases may be over-diagnosed with partial pharyngeal collapse. Further studies comparing nasopharyngeal luminal changes between clinically healthy brachycephalic dogs and dogs with respiratory signs are warranted.

Flat-Faced or Non-Flat-Faced Cats? That Is the Question

Persian and exotic shorthair cats are the most-popular brachycephalic breeds worldwide. This study aimed to explore differences in human-cat bonding, behavioural traits, perception of clinical breed-related problems, and the motivation for purchasing between brachycephalic cat owners (BCOs) and non-brachycephalic cat owners (NBCOs). Using an online questionnaire, human-cat bonding and cats' behavioural traits were explored using the CORS and Fe-BARQ scales, respectively. Breed-related problems and motivations for purchasing were explored only in BCOs. There were 278 BCOs and 250 NBCOs who completed the survey. Respiratory diseases resulted in being the main health problem of these breeds. Most BCOs were not aware of the incidence of these disorders in brachycephalic cats. Character and appearance were the main motivations for purchasing these breeds. Perceived emotional closeness (EC), cat-owner interaction (COI), and perceived cost (PC) mean scores were significantly higher in BCOs. Playfulness and affection-/attention-seeking scores were significantly higher in NBCOs. BCOs reported a significantly higher score for separation-related behaviours. The higher scores in separation-anxiety-related behaviours and in the EC and COI scales could be related mainly to the high level of care these breeds require. The motivation for acquiring brachycephalic breeds for good companionship seems in contrast with the lower scores obtained from BCOs for playfulness and affection-/attention-seeking.

Evaluation of blood pressure and NT-proBNP in pugs with and without clinical signs of Brachycephalic Obstructive Airway Syndrome

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.

Dynamics of early stages of nose morphogenesis

The formation of sensory organs is an important developmental and evolutionary question. In the context of regenerative medicine also, it is important to know as accurately as possible how sensory organs form. The formation of ears, eyes or nose stems presumably from tissue thickenings called placodes Graham and Shimeld (J Anat 222(1):32-40, 2013), Horie et al. (Nature 560:228-232, 2018) which become these organs after processes termed inductions. However, the origin of the placodes, the mechanism of induction and the overall face organization are not understood. Recently, it has been suggested that there is a physical principle to face organization. Indeed, it has been shown that there exists a pattern of rings and rays in the early blastula which defines the position of face landmarks, especially the ears and eyes Fleury et al. (Second order division in sectors as a prepattern for sensory organs in vertebrate development, 2021), Fleury and Abourachid (Eu Phys J E 45:31, 2022). Tensions in the sectors defined by the intersections of the said rings and rays create the actual face features. I report here that a similar situation exists for the nose. This explains the robustness of face formation in the chordates phylum. By studying nasal pit formation in the chicken embryo by time-lapse (T-L) video microscopy, I show that the nasal placode originates in a narrow sector deformed by tension forces following the biaxial pattern of rings and rays mentioned above. Cells align in the pattern and exert organized forces. Further contractions of the pattern contribute to inducing the nasal pit. The observation of the early pre-pattern of lines which locks the facial features explains readily a number of facts regarding sensory organs. Especially the existence of a lacrimal canal between the eye and the nose Lefevre and Freitag (Semin Ophthalmo l 27(5-6):175-86, 2012), or of a slit connecting the nose to the mouth, the correlation between nose, mouth and eye morphogenesis Dubourg et al. (J Rare Dis 2(8), 2007), the presence of shallow valleys on the nasal and optic vesicles, the medio-lateral asymmetry of nostrils with often a bent slit Liu et al. (PLoS ONE 12: e0181928, 2017), the uneven number of nostrils in many fish Cox (J R Soc Interf 5(23):575-593, 2008) and possibly the transition between agnatha and gnathostomes Gai and Zhu (Chinese Sci Bull 57(31), 2012): all appear under this light, geometrically straightforward. The nasal pit forms in a sector of tissue which was present on the blastodic (early embryonic stage), and which is projected onto the nasal vesicle during neurulation. The nasal pit forms along a hairpin of tissue. The top part of the hairpin forms the nares, and the bottom part a groove often visible in many animals.

[Assessment of clinical signs of brachycephalic obstructive airway syndrome and other breed-specific diseases in pug dogs - an online survey]

OBJECTIVE

The aim of the study was to investigate the awareness for the breed-related brachycephalic obstructive airway syndrome (BOAS) and the occurrence of other breed-typical diseases within the framework of an online survey for pug owners.

MATERIAL AND METHODS

A digital questionnaire for owners was created, distributed via social media and subsequently evaluated.

RESULTS

The questionnaire was completed by 1220 pug owners. According to the owners, 32 % (344/1073) of the animals that did not undergo airway dilatation surgery show slight and 3 % (34/1073) show distinct breathing sounds when at rest. 86 % (326/378) of the owners perceive these breathing sounds as "normal, breed-specific" and 14 % (51/378) consider them as sign of "disease". 20 % (210/1073) of the animals are considered "somewhat" and 5 % (57/1073) "frequently tired and quickly short of breath" after a small amount of time. 24 % (245/1220) of all animals suffer from ocular diseases, 10 % (122/1220) from skin diseases and 11 % (134/1220) from spinal diseases, among others.

CONCLUSION

The survey shows that with 67 % (814/1220) more than half of the pug owners perceive clinical signs of BOAS and/or other breed-specific diseases in their animals, however, a large proportion consider these as being non-problematic.

CLINICAL RELEVANCE

The present study reveals that the animals' clinical limitations associated with brachycephaly are oftentimes not perceived as being pathologic and are hence underestimated by the owners.

Assessment of Nasal Structure Using CT Imaging of Brachycephalic Dog Breeds

The response to treatment of brachycephalic airway syndrome (BAS) varies among brachycephalic dog breeds. We hypothesized that variations in nasal structure are one of the factors responsible for this difference. To confirm this variation, we measured the ratio of the airway cross-sectional area to the total nasal cavity area (AA/NC) in three brachycephalic dog breeds. Head CT images of French bulldogs, shih tzus, and pugs were retrospectively collected. Four specific transverse planes were used to calculate AA/NC ratios. Fifty brachycephalic dogs were included in the study: French bulldogs (n = 20), shih tzus (n = 20), and pugs (n = 10). The AA/NC ratio of Shih Tzus was larger in the rostral nasal cavity and smaller toward the caudal area, whereas the other two breeds showed an inverse tendency. The results obtained from the current research indicate that the AA/NC ratio can be used to evaluate the structure of the nasal cavity. Moreover, analyzing the point with the smallest AA/NC ratio can be useful in quantifying nasal airway obstruction and the severity of BAS. These results will be useful in understanding the complexity of BAS pathophysiology and in the implementation of treatment.

Evaluation of a Treadmill-Based Submaximal Fitness Test in Pugs, and Collecting Breed-Specific Information on Brachycephalic Obstructive Airway Syndrome

Simple Summary

In the present study, a submaximal fitness test on a treadmill was evaluated to assess its feasibility under standardised conditions. Moreover, its effectiveness in identifying pugs with clinical signs of brachycephalic obstructive airway syndrome was examined. It was apparent that respiratory symptoms can be exposed during the fitness test, and intensified with an increased duration of exercise. This method of testing improves the clinical evaluation of the dogs and helps identify restrictions due to brachycephalic obstructive airway syndrome. Since most of the dogs could be familiarised with the treadmill, it may be a feasible option for performing fitness tests in brachycephalic dogs. Major benefits, therefore, are that each dog can be closely monitored during the entire process, and that the examination can be conducted under standardised conditions.

Abstract

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.

English Bulldogs in the UK: a VetCompass study of their disorder predispositions and protections

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.

Health of Pug dogs in the UK: disorder predispositions and protections

BACKGROUND

Pugs are a brachycephalic dog breed that has become phenomenally popular over recent decades. However, there is growing concern about serious health and welfare issues in the breed. To augment the evidence-base on the comparative health of Pugs, this study aimed to compare the odds of common disorders between Pugs and all remaining dogs under primary veterinary care in the UK during 2016. A cross-sectional study design of VetCompass clinical records was used to estimate the one-year (2016) period prevalence for the disorders most commonly diagnosed in Pugs and non-Pugs. Risk factor analysis applied multivariable logistic regression modelling methods to compare the odds of 40 common disorders between Pugs and non-Pugs.

RESULTS

From a study population of 905,544 dogs, the analysis included random samples of 4308 Pugs and 21,835 non-Pugs. Pugs were younger (2.36 years, range 0.07-16.24 vs 4.44 years, range 0.01-20.46, p <  0.001) and lighter (8.95 kg, range 5.00-13.60 vs. 14.07 kg, range 1.41-85.00, p <  0.001) than non-Pugs. Pugs had 1.86 (95% confidence interval [CI] 1.72 to 2.01) times the adjusted odds of diagnosis with ≥1 disorder than non-Pugs. Pugs had significantly increased adjusted odds for 23/40 (57.5%) common disorders. These included: brachycephalic obstructive airway syndrome (odds ratio [OR] 53.92; 95% CI 36.22 to 80.28), stenotic nares (OR 51.25; 95% CI 24.93 to 105.37) and corneal ulceration (OR 13.01; 95% CI 10.50 to 16.11). Conversely, Pugs had significantly reduced adjusted odds of 7/40 (17.5%) common disorders compared to non-Pugs. These included: heart murmur (OR 0.23; 95% 0.13 to 0.14), lipoma (OR 0.24; 95% CI 0.11 to 0.55) and aggression (OR 0.31; 95% CI 0.21 to 0.47).

CONCLUSIONS

The current study highlights that predispositions outnumber protections between Pugs and non-Pugs for common disorders, suggesting some critical health welfare challenges to overcome for Pugs. Highly differing heath profiles between Pugs and other dogs in the UK suggest that the Pug has diverged substantially from mainstream dog breeds and can no longer be considered as a typical dog from a health perspective.

Incidence of alimentary and respiratory disease in brachycephalic dogs presenting to primary care veterinary practices participating in the SAVSNET project

BACKGROUND

Brachycephalic dogs clinically affected by brachycephalic obstructive airway syndrome have been shown to have a high incidence of gastrointestinal disease, with French Bulldogs (FBD) identified as a particularly affected breed.

METHODS

Clinical records of 750 brachycephalic dogs attending over 500 practices participating in the small animal veterinary surveillance network (SAVSNET) project were analysed in this cohort study to determine the incidence of alimentary and respiratory disease within FBD, Bulldogs (BD) and Pugs attending primary care veterinary practice. Electronic clinical records were studied for treatment or acknowledgement of specific clinical signs that could be attributed to different anatomical locations. Disease of the different anatomical locations was marked as either being present or not present which allowed for statistical analysis.

RESULTS

Significant differences in the incidence of oesophageal (p = 0.006), gastric (p = 0.001) and intestinal (p = 0.001) diseases were present among the breeds studied. FBD had significantly increased odds ratios of having oesophageal (2.0, 2.2), gastric (2.4, 1.5) and intestinal (1.7, 1.5) diseases relative to Pugs and BD, respectively. Pugs had significantly increased odds ratios of having upper respiratory tract disease relative to BD (1.9).

CONCLUSION

The results show the incidence of gastrointestinal disease and upper respiratory tract disease is significantly different between the brachycephalic breeds studied. Furthermore, the general population of FBD has the highest incidence of gastrointestinal disease.

Lead pulling as a welfare concern in pet dogs: What can veterinary professionals learn from current research?

Veterinary professionals (VPs) are often the first source of advice for clients struggling with their dog's behaviour, and pulling on the lead is a commonplace undesirable behaviour VPs will encounter regularly in practice. Excluding bites, being pulled over while walking on a lead is the leading cause of non-fatal dog-related injuries in the UK. This narrative review investigates lead pulling as a welfare concern in pet dogs, highlighting aspects of the literature of particular interest to VPs. Lead pulling could negatively affect walk quality, frequency and duration, causing weight gain, while decreased environmental enrichment could trigger other undesirable behaviours. Aversive equipment to prevent lead pulling can cause pain, distress and injury, but even equipment considered humane can have welfare consequences. Punitive training methods could cause dogs stress, fear and anxiety and trigger aggressive behaviour. While these lead pulling outcomes are welfare concerns in themselves, they could also weaken dog-owner attachment, a risk factor in pet dog relinquishment. Given lead pulling could affect the welfare of patients in a VPs care, clinical implications and opportunities for client education are outlined. Educating clients on humane prevention and modification of lead pulling could make walks easier, safer and more enjoyable, with positive outcomes for clients, canine welfare and the practice.

Association of gastric lymphofollicular hyperplasia with Helicobacter-like organisms in dogs

Background

The relationships among gastric lymphoid follicular hyperplasia (GLFH), Helicobacter‐like organisms (HLOs), and clinical signs have not been established in dogs.

Objectives

To evaluate the epidemiologic, clinical, endoscopic, and histopathologic findings associated with GLFH in dogs, and determine the association of GLFH with HLOs and the French Bulldog (FB) breed.

Animals

Two hundred eighty‐eight dogs that underwent gastroscopy between 2013 and 2016.

Methods

Retrospective, cross‐sectional study. Gastric biopsy samples were reviewed and scored for inflammation and HLOs. Dogs were divided into 3 groups: group 1 (63 FBs), group 2 (45 non‐FB brachycephalic dogs), and group 3 (180 nonbrachycephalic dogs). Variables were evaluated for their association with GLFH.

Results

Univariate analysis determined that intact males, young age, vomiting, gastroscopic findings (discoloration, hemorrhage, and ulcers), and histopathologic findings (gastric lamina propria lymphocytic infiltration and HLO score) were associated with GLFH (P ≤ .03). In the multivariate analysis, GLFH was associated with the HLO score (odds ratio [OR] > 5 for HLO scores 1‐2 and >15 for HLO score of 3; P < .001), with vomiting (OR > 4; P = .01) but not with FB breed (P = .76) and age (P = .1). The HLO score was associated with younger age (P < .001).

Conclusion and Clinical Importance

The HLO score was associated with a high GLFH score. Vomiting was associated with GLFH. Helicobacter‐like organisms are highly prevalent in young dogs and GLFH is indirectly associated with this factor. Clinical relevance of the identification of GLFH and HLO remains to be determined.

French Bulldogs differ to other dogs in the UK in propensity for many common disorders: a VetCompass study

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.

The French Bulldog is currently a hugely popular dog breed in the UK. However, the breed is linked with a range of serious health issues. Using veterinary clinical data from the VetCompass Programme at the Royal Veterinary College, this study aimed to compare the frequency of common disorders in French Bulldogs against that of all remaining dogs to identify health strengths and weaknesses in French Bulldogs. This overall view of breed health can assist owners, breeders and veterinarians to take appropriate actions to improve the health of French Bulldogs.

From an overall population of 905,544 dogs, random samples of 2,781 French Bulldogs and 21,850 non-French Bulldogs were included in the analysis. French Bulldogs were younger (1.51 years versus 4.48 years) and lighter (12.45 kg versus 13.80 kg) than non-French Bulldogs. French Bulldogs had increased risk of 20/43 (46.5 %) specific disorders and decreased risk of 11/43 (25.6 %) specific disorders compared to non-French Bulldogs. The disorders with greatest relative risk in French Bulldogs compared to non-French Bulldogs were narrowed nostrils (x 42.14), Brachycephalic Obstructive Airway Syndrome (x 30.89), ear discharge (x 14.40), skin fold dermatitis (x 11.18) and difficulty giving birth [dystocia] (x 9.13). When the disorders were grouped into broad disease categories, French Bulldogs had increased risk of 12/32 (37.5 %) disorder groups and reduced risk of 6/32 (18.8 %) disorder groups compared to non-French Bulldogs.

This study suggests that the health of French Bulldogs is very different, and largely much poorer, that the health of the wider non-French Bulldog population. Many of these differences are closely associated with the extreme body shape that defines the French Bulldog breed. Shifting the body shape of French Bulldogs to become more moderate, and hence less extreme, is proposed as a logical opportunity to reduce the current serious and common health issues in the French Bulldog breed.

Influence of Morphometry on Echocardiographic Measurements in Cavalier King Charles Spaniels: An Inverse Probability Weighting Analysis

The development and progression of myxomatous mitral valve disease (MMVD) in Cavalier King Charles Spaniels (CKCS) are difficult to predict. Thus, the identification of dogs with a morphotype associated with more severe mitral disease at a young age is desirable. The aims of this study were to: (1) describe the physical, morphometric, and echocardiographic features of class B1 MMVD-affected Cavalier King Charles Spaniels (CKCS) according to the American College of Veterinary Internal Medicine (ACVIM) guidelines; (2) evaluate the influence of morphometric physical measurements on murmur intensity, mitral valve prolapse (MVP), regurgitant jet size, and indexed mitral valve and annulus measurements. Fifty-two MMVD-affected CKCS were included in the ACVIM class B1. This is a prospective clinical cross-sectional study. Morphometric measurements, which included the body, thorax, and head sizes of each dog, were investigated to establish the association with heart murmur intensity, valvular and annular echocardiographic measurements, MVP, and regurgitant jet size, using inverse probability weighting (IPW) analyses to adjust for confounding. The IPW analyses showed that when the head length and nose length decreased, dogs had a more severe regurgitant jet size. Furthermore, subjects with a more pronounced head stop angle had thicker anterior mitral valve leaflets. A brachycephalic morphotype, as seen in dogs similar to the King Charles Spaniel breed in terms of cephalic morphology, is associated with a more severe regurgitant jet size and with valvular characteristics that are related to the most severe forms of MMVD.

Evaluating malformations of the lacrimal drainage system in brachycephalic dog breeds: A comparative computed tomography analysis

OBJECTIVES

This study aimed to investigate and compare the anatomical features of the nasolacrimal drainage system (NDS) in three brachycephalic dog breeds with those of normocephalic dogs, taking into account how the NDS was related to the malformed brachycephalic head.

ANIMALS

Fifty-one brachycephalic dogs were examined, comprising 23 Pugs, 18 French Bulldogs, and 10 English Bulldogs. Six normocephalic dogs of different breeds served as a comparison.

METHODS

Computed tomographic dacryocystography was performed. Parameters such as length, angulation, and gradient were determined. Crossing of the nasolacrimal duct (NLD) beneath the maxillary canine root, as well as the incidence of an accessory opening, were also analyzed.

RESULTS AND CONCLUSIONS

In all three brachycephalic breeds, the NDS was grossly malformed. We regard this as a further consequence of exaggerated breeding for a short head conformation. While the length of the NLD was substantially reduced by 41 to 57 percent in brachycephalic dogs, their lacrimal canaliculi were two to three times as long as those of normocephalic dogs. Varying parts of the nasolacrimal drainage system followed an inverse direction in short-headed dogs, giving the entire nasolacrimal apparatus an anomalous U- or V-shaped appearance. The NLD exhibited a three to five times steeper alignment in brachycephalic dogs than in normocephalic ones. Obviously, this strong slope did not cause clinical symptoms only because there was an aberrant outflow pathway. The brachycephalic dogs consistently exhibited an accessory opening, through which most of fluid escaped into the posterior nasal cavity instead of through the common route into the nasal vestibule via the nasolacrimal ostia.