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Brachycephalic breeds are often in the news due to the challenges and ethical issues surrounding conformation-related disease in these breeds. An exponential rise in ownership of brachycephalic breeds has occurred in recent years, particularly of French bulldogs, where kennel club registrations have increased by 3000 per cent over the past 10 years in the UK. The increase in popularity of these breeds has led to increased awareness of conformation-related health issues seen in some brachycephalic dogs. Brachycephalic obstructive airway syndrome (BOAS) is perhaps the most obvious conformation-related health issue, but other welfare issues include: skin fold pyoderma; shallow orbits with protruding globes, leading to increased risk of corneal ulceration and globe prolapse; hemivertebrae, which may be accompanied by spinal cord compression; Chiari-like malformation; dystocia; and dental malocclusion. Upper airway obstruction, or BOAS, has been predominantly documented in extreme brachycephalic breeds, specifically the bulldog, French bulldog and pug. BOAS may manifest as respiratory noise, dyspnoea, exercise intolerance, heat sensitivity, sleep disorders, cyanosis or collapse.1 The prevalence of these diseases among the brachycephalic breeds is difficult to assess as many are not recognised by owners2 and some are accepted by veterinary surgeons as normal for the breed. Although many breeds, including the French bulldog, pug and bulldog, have health schemes which the breed clubs are promoting, only a small proportion of the pet population is Kennel Club registered. The increased demand for these dogs has resulted in a lucrative puppy trade where the focus may be on money rather than health. The general practice surveillance data generated from schemes such as VetCompass have shown that extreme brachycephalic breeds die younger than equivalent sized dogs, with a higher proportion of deaths due to upper respiratory disease.3 However, the value of such information depends on accurate, consistent reporting of lesions which, …

Objective To determine prognostic indicators for the surgical treatment of brachycephalic obstructive airway syndrome (BOAS) and to compare the prognosis of 2 multilevel surgical procedures. Study Design Prospective clinical study. Sample Population Client-owned pugs, French bulldogs, and bulldogs (n = 50). Methods Noninvasive whole-body barometric plethysmography (WBBP) was used to assess respiratory function before, 1 month and 6 months after upper airway corrective surgery. Postoperatively, BOAS indices (ie, ascending severity score generated from WBBP data, 0%-100%) that equaled to or exceeded the cut-off values of BOAS in the diagnostic models were considered to have a “poor prognosis.” A multivariate logistic regression was used to assess predictors for prognosis. Results The median BOAS indices decreased after surgery (from 76% to 63%, P

Background A novel test using whole-body barometric plethysmography (WBBP) was developed recently to diagnose brachycephalic obstructive airway syndrome (BOAS) in unsedated French bulldogs. Hypothesis/Objectives The hypotheses of this study were: (1) respiratory characteristics are different between healthy nonbrachycephalic dogs and brachycephalic dogs; and among pugs, French bulldogs, and bulldogs; and (2) obesity and stenotic nares are risk factors for BOAS. The main objective was to establish a diagnostic test for BOAS in these 3 breeds. Animals A total of 266 brachycephalic dogs (100 pugs, 100 French bulldogs, and 66 bulldogs) and 28 nonbrachycephalic dogs. Methods Prospective study. Exercise tolerance tests with respiratory functional grading, and WBBP were performed on all dogs. Data from WBBP were associated with functional grades to train quadratic discriminant analysis tools to assign dogs to BOAS+ and BOAS- groups. A BOAS index (0–100%) was calculated for each dog. Receiver operating characteristic (ROC) curves were used to evaluate classification ability. Results Minute volume was decreased significantly in asymptomatic pugs (P = .009), French bulldogs (P = .026), and bulldogs (P < .0001) when compared to nonbrachycephalic controls. Respiratory characteristics were different among breeds and affected dogs had a significant increase in trace variation. The BOAS index predicted BOAS status for each breed with 94–97% (95% confidence interval [CI], 88.9–100%) accuracy (area under the ROC curve). Both obesity (P = .04) and stenotic nares (P = .004) were significantly associated with BOAS. Conclusions and Clinical Importance The WBBP can be used as a clinical tool to diagnose BOAS noninvasively and objectively.

The Ca(2+) -binding protein S100A4 interacts with the C terminus of nonmuscle myosin IIA (NMIIA) causing filament disassembly, which is correlated with an increased metastatic potential of tumor cells. Despite high sequence similarity of the three NMII isoforms, S100A4 discriminates against binding to NMIIB. We searched for structural determinants of this selectivity. Based on paralog scanning using phage display, we identified a single position as major determinant of isoform selectivity. Reciprocal single amino acid replacements showed that at position 1907 (NMIIA numbering), the NMIIA/NMIIC-specific alanine provides about 60-fold higher affinity than the NMIIB-specific asparagine. The structural background of this can be explained in part by a communication between the two consecutive α-helical binding segments. This communication is completely abolished by the Ala-to-Asn substitution. Mutual swapping of the disordered tailpieces only slightly affects the affinity of the NMII chimeras. Interestingly, we found that the tailpiece and position 1907 act in a nonadditive fashion. Finally, we also found that the higher stability of the C-terminal coiled-coil region of NMIIB also discriminates against interaction with S100A4. Our results clearly show that the isoform-selective binding of S100A4 is determined at multiple levels in the structure of the three NMII isoforms and the corresponding functional elements of NMII act synergistically with one another resulting in a complex interaction network. The experimental and in silico results suggest two divergent evolutionary pathways: NMIIA and NMIIB evolved to possess S100A4-dependent and -independent regulations, respectively.

Computed tomography (CT) is used to document upper airway lesions in dogs with brachycephalic obstructive airway syndrome. The presence of an endotracheal tube during CT scanning is often required for general anesthesia. We hypothesized that the endotracheal tube placement would change the soft tissue dimensions of the upper airway. The aims of this prospective, method comparison study were to evaluate the reliability of the previously reported upper airway CT measurements with endotracheal tube placement, and to propose measurements that are minimally affected by the endotracheal tube. Twenty brachycephalic dogs were included in this study. Each dog underwent head/neck CT with an endotracheal tube, followed by a second scan without the endotracheal tube. Ten measurements of the soft palate, nasopharynx, and trachea were performed. Tracheal dimension was significantly larger with the endotracheal tube compared to without, whereas the soft palate cross-sectional area was significantly smaller with the endotracheal tube than without the endotracheal tube. The influence of the endotracheal tube on the caudal nasopharynx cross-sectional (transverse-sectional) area varied with a mean proportional absolute difference of 35%. Rostral soft palate thickness, tracheal perimeter, and cross-sectional area of the rostral nasopharynx were the measurements least affected by the endotracheal tube (intraclass correlation coefficient = 0.964, 0.967, and 0.951, respectively). Therefore, we proposed that these three measurements may be most useful for future brachycephalic obstructive airway syndrome studies that require CT scanning of intubated animals. However, with endotracheal tube placement, measurements of soft palate length, caudal nasopharyngeal cross-sectional area, and trachea height and width may not be reliable.

Non-invasive sampling is a useful tool for genetic analyses of endangered and1or elusive species, but it is often inapplicable due to the low quality and quantity of the DNA obtained. In this study we show that the blood clot located in the superior umbilicus of the feather shaft is a better source of DNA than the previously used tip samples from moulted feathers. We found that feather clots from museum specimens provided results nearly as good as footpad and better than those from the more commonly used museum skin snips. Feather clots proved to be a good source of DNA for genetic analysis that will significantly facilitate genetic monitoring of wild bird populations.