West Highland White Terriers under primary veterinary care in the UK in 2016: demography, mortality and disorders

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

BACKGROUND

Shih Tzus are a popular dog breed in the UK although there is relatively little reported information on their health. This study aimed to characterise the demography, common disorders and mortality of Shih Tzus under primary veterinary care during 2016 in the UK using de-identified clinical records from the VetCompass™ Programme.

RESULTS

The study population of 336,865 dogs under veterinary care during 2016 included 11,082 Shih Tzus (3.3%). The median age was 4.1 years (IQR: 2.1-7.1, range: 0.3-20.4) and mean adult bodyweight was 7.9 kg (SD: 1.9 kg). Annual proportional births increased from 2.2% of all dog births in 2005 to 3.8% in 2013, dropping to 3.3% by 2016. From a random subset of 2,423 Shih Tzus that had information extracted on disorders diagnosed during 2016, the most prevalent fine-level precision disorders were periodontal disease (n = 229, prevalence 9.5%, 95% CI: 8.4-10.7), anal sac impaction (180, 7.4%, 95% CI: 6.5-8.5) and ear disorders (134, 5.5%, 95% CI: 4.7-6.5). The most prevalent grouped-level precision disorders were cutaneous (n = 402, prevalence: 16.6%, 95% CI: 15.2-18.1), dental (322, 13.3%, 95% CI: 12.0-14.7), and ophthalmological (289, 11.9%, 95% CI: 10.7-13.3). Males were more likely than females to be diagnosed with skin disorders (P = 0.007) and musculoskeletal disorders (P = 0.010) while females were more likely than males to be diagnosed with hernias (P = 0.005). The median age of death was 12.7 years (IQR 8.7-14.3, range 2.0-19.9) and did not differ statistically between males and females. The most common grouped causes of death were enteropathy (7.9%, 95% CI: 3.9-15.4), heart disease (7.9%, 95% CI: 3.9-15.4) and poor quality of life (7.9%, 95% CI: 3.9-15.4).

CONCLUSIONS

Periodontal disease, anal sac impaction and ear disorders were identified as common health issues. Shih Tzus had higher prevalence of anal sac impaction, umbilical hernias and eye problems than reported previously in dogs overall, suggesting potential predispositions. Shih Tzus appear to be relatively long-lived compared to previous reports of lifespan in dogs overall. The results can inform veterinarians and owners on priority disorders for monitoring to protect welfare. Oral hygiene was highlighted as a healthcare priority.

Demography and disorders of English Cocker Spaniels under primary veterinary care in the UK

BACKGROUND

The English Cocker Spaniel (ECS) is a common family dog in the UK. This study aimed to describe demography, morbidity, and mortality in ECS under primary veterinary care in the UK during 2016 using data from the VetCompass™ Programme. This study hypothesised that the prevalence of aggression is higher in male than female ECS, and higher in solid-coloured than bi-coloured ECS.

RESULTS

English Cocker Spaniels comprised 10,313/336,865 (3.06%) of dogs under primary veterinary care during 2016. The median age was 4.57 years (inter-quartile range (IQR) 2.25-8.01) and the median adult bodyweight was 15.05 kg (IQR 13.12-17.35). The annual proportional birth rate was relatively stable between 2.97-3.51% from 2005-2016. The most common specific diagnoses were periodontal disease (n = 486, prevalence 20.97%, 95% confidence interval (CI): 19.31-22.62), otitis externa (n = 234, 10.09%, 95% CI: 8.87-11.32), obesity (n = 229, 9.88%, 95% CI: 8.66-11.09), anal sac impaction (n = 187, 8.07%, 95% CI: 6.96-9.18), diarrhoea (n = 113, 4.87%, 95% CI: 4.00-5.75), and aggression (n = 93, 4.01%, 95% CI: 3.21-4.81). The prevalence of aggression was higher in males (4.95%) than in females (2.87%) (P = 0.015) and in solid-coloured (7.00%) than in bi-coloured dogs (3.66%) (P = 0.010). The median age at death was 11.44 years (IQR 9.46-13.47) and the most common grouped causes of death were neoplasia (n = 10, 9.26%, 95% CI: 3.79-14.73), mass-associated disorders (n = 9, 8.33%, 95% CI: 4.45-15.08), and collapse (n = 8, 7.41%, 95% CI: 3.80-13.94).

CONCLUSIONS

Periodontal disease, otitis externa, and obesity are identified as the most common health issues for ECS, and neoplasia and mass-associated disorders as the most common reasons for death. The prevalence of aggression was higher in males and solid-coloured dogs. The results can aid veterinarians in giving evidence-based health and breed choice information to dog owners and highlights the importance of thorough oral examination and body condition score evaluation during routine veterinary examination of ECS.

Idiopathic generalised tremor syndrome in dogs

BACKGROUND

Idiopathic generalised tremor syndrome (IGTS) causes tremor and often vestibulocerebellar signs. Previous publications on IGTS in dogs are restricted to case reports or lack exclusion of structural causes.

METHODS

Medical records of 75 dogs diagnosed with IGTS that had undergone magnetic resonance imaging (MRI) of the brain were collected retrospectively.

RESULTS

Crossbreeds were affected most commonly (41.3%), followed by West Highland white terriers (14.7%) and cocker spaniels (10.7%). A higher proportion of females were affected than males (68.0%). Median age of the affected dogs was 17 months (range 6-121 months), and median bodyweight was 9.15 kg (range 2.9-26 kg). All dogs presented with tremors and most experienced concomitant neurological signs (93.3%). Seventeen (22.7%) were hyperthermic and 31 (41.3%) had gastrointestinal signs. MRI of the brain was normal in most of the cases, and cerebrospinal fluid analysis frequently revealed mild pleocytosis. All animals were treated with prednisolone, and 39 (51.3%) also received diazepam. Median follow-up time was 13 months (range 0-134 months). The overall outcome was good, although 16 (21.3%) patients were reported to have relapsing clinical signs and 10 (13.2%) patients experienced persistent mild clinical signs.

CONCLUSIONS

IGTS should be suspected in any dog with generalised tremor and vestibulocerebellar signs with younger and smaller dogs more commonly affected.

Frequency and predisposing factors for canine otitis externa in the UK - a primary veterinary care epidemiological view

BACKGROUND

Otitis externa is a commonly diagnosed disorder in dogs and can carry a high welfare impact on affected animals. This study aimed to report the prevalence and explore the role of breed and aural conformation as predisposing factors for canine otitis externa in the UK. The study used a cohort design of dogs under UK primary veterinary care at clinics participating in the VetCompass Programme during 2016. Risk factor analysis used multivariable logistic regression modelling.

RESULTS

The study included a random sample of 22,333 dogs from an overall population of 905,554 dogs under veterinary care in 2016. The one-year period prevalence of otitis externa was 7.30% (95% confidence interval [CI]: 6.97 to 7.65). Breed and ear carriage were the highest ranked risk factors. Compared with crossbred dogs, sixteen breed types showed increased odds, including: Basset Hound (odds ratio [OR] 5.87), Chinese Shar Pei (OR 3.44), Labradoodle (OR 2.95), Beagle (OR 2.54) and Golden Retriever (OR 2.23). Four breeds showed protection (i.e. reduced odds) of otitis externa: Chihuahua (OR 0.20), Border Collie (OR 0.34), Yorkshire Terrier (OR 0.49) and Jack Russell Terrier (OR 0.52). Designer breed types overall had 1.63 times the odds (95% CI 1.31 to 2.03) compared with crossbred dogs. Compared with breeds with erect ear carriage, breeds with pendulous ear carriage had 1.76 times the odds (95% CI 1.48 to 2.10) and breeds with V-shaped drop ear carriage had 1.84 times the odds (95% CI 1.53 to 2.21) of otitis externa.

CONCLUSIONS

Breed itself and breed-associated ear carriage conformation are important predisposing factors for canine otitis externa. Greater awareness of these associations for both predisposed and protected breeds could support veterinary practitioners to promote cautious and low-harm approaches in their clinical advice on preventive care for otitis externa, especially in predisposed breeds.

Epidemiology of periodontal disease in dogs in the UK primary-care veterinary setting

Objectives

Periodontal disease is a frequent diagnosis of dogs and can have severe negative impacts on welfare. It was hypothesised that breeds with skull shapes that differ most in conformation from the moderate mesocephalic skull shape have higher odds of periodontal disease.

Materials and Methods

The cohort study included a random sample of dogs under primary veterinary care in 2016 from the VetCompass Programme database. Risk factor analysis used random effects multivariable logistic regression modelling.

Results

The study included a random sample of 22,333 dogs. The 1‐year period prevalence for diagnosis with periodontal disease was 12.52% (95% CI: 12.09 to 12.97). Eighteen breeds showed increased odds compared with crossbred dogs. Breeds with the highest odds included Toy Poodle (odds ratio 3.97, 95% confidence intervals 2.21 to 7.13), King Charles Spaniel (odds ratio 2.63, 95% confidence interval 1.50 to 4.61), Greyhound (odds ratio 2.58, 95% confidence interval 1.75 to 3.80) and Cavalier King Charles Spaniel (odds ratio 2.39, 95% confidence interval 1.85 to 3.09). Four breeds showed reduced odds compared with crossbreds. Brachycephalic breeds had 1.25 times the odds (95% confidence interval 1.11 to 1.42) of periodontal disease compared with mesocephalic breeds. Spaniel types had 1.63 times the odds (95% confidence interval 1.42 to 1.87) compared with non‐spaniel types. Increasing adult bodyweight was associated with progressively decreasing odds of periodontal disease.

Clinical Significance

The high prevalence identified in this study highlights periodontal disease as a priority welfare concern for predisposed breeds. Veterinarians can use this information to promote improved dental care in predisposed dogs, especially as these dogs age.

Frequency, breed predisposition and demographic risk factors for overweight status in dogs in the UK

OBJECTIVES

To evaluate the prevalence and risk factors for overweight status in dogs under primary veterinary care in the UK.

MATERIALS AND METHODS

A retrospective study design was used to estimate the 1-year (2016) period prevalence of overweight status. The clinical records were randomly ordered and manually validated for dogs with overweight status during 2016. Univariable and multivariable logistic regression modelling were used to evaluate associations between risk factors (breed, brachycephalic status, adult bodyweight, bodyweight relative to breed-sex mean, age, sex-neuter and insurance) and overweight status.

RESULTS

There were 1580 of 22,333 dogs identified as overweight during 2016. The estimated 1-year period prevalence for overweight status recorded in dogs under veterinary care was 7.1% (95% confidence interval 6.7-7.4). After accounting for confounding factors, eight breeds showed increased odds of overweight status compared with crossbred dogs. The breeds with the highest odds included the Pug (OR 3.12, 95% confidence interval 2.31 to 4.20), Beagle (OR 2.67, 1.75 to 4.08), Golden Retriever (OR 2.58, 1.79 to 3.74) and English Springer Spaniel (OR 1.98, 1.31 to 2.98). Being neutered, middle-aged and insured were additionally associated with overweight status.

CLINICAL SIGNIFICANCE

Targeted overweight prevention strategies should be prioritised for predisposed breeds, such as Pugs and Beagles. The findings additionally raise questions about further preventative efforts following neutering. The prevalence estimate suggests veterinary professionals are underreporting overweight status and therefore could be missing key welfare opportunities.

Dog breeds and body conformations with predisposition to osteosarcoma in the UK: a case-control study

Background

Osteosarcoma is an aggressive and painful bone neoplasm in dogs. Previous studies have reported epidemiological associations suggesting that large body mass, long bone length and the genetics of certain breeds including the Rottweiler are associated with elevated osteosarcoma risk. However, these studies were often limited by selection bias and confounding factors, and have rarely offered insights into breed-associated protection for osteosarcoma. The current study includes 1756 appendicular and axial osteosarcoma cases presenting to VPG Histology (Bristol, UK) compared against a control population of 905,211 dogs without osteosarcoma from primary care electronic patient records in the VetCompass™ dataset.

Methods and study design

Retrospective, case-control study. Multivariable logistic regression analysis explored associations between demographic risk factors (including breed, chondrodystrophy, age, sex/neuter status, skull-shape, and body mass) and osteosarcoma of all anatomical sites.

Results

We identified several breeds with increased and reduced odds of osteosarcoma. At highest risk were the Rottweiler and Great Dane, with > 10 times the odds of osteosarcoma compared with crossbreds, and the Rhodesian Ridgeback, which has not featured in previous lists of at-risk breeds for osteosarcoma, and had an odds ratio of 11.31 (95% confidence interval 7.37–17.35). Breeds at lowest risk of osteosarcoma (protected breeds) included the Bichon Frise, the French Bulldog and the Cavalier King Charles Spaniel, all with odd ratios of less than 0.30 compared with crossbreds. Body mass was strongly associated with osteosarcoma risk; dogs over 40 kg exhibited osteosarcoma odds of 45.44 (95% confidence interval 33.74–61.20) compared with dogs less than 10 kg. Chondrodystrophic breeds had an osteosarcoma odds ratio of 0.13 (95% confidence interval 0.11–0.16) compared with non-chondrodystrophic breeds.

Conclusions

This study provides evidence of strong breed-associated osteosarcoma risk and protection, suggesting a genetic basis for osteosarcoma pathogenesis. It highlights that breeds selected for long legs/large body mass are generally overrepresented amongst at-risk breeds, whilst those selected for short leg length/small body mass are generally protected. These findings could inform genetic studies to identify osteosarcoma risk alleles in canines and humans; as well as increasing awareness amongst veterinarians and owners, resulting in improved breeding practices and clinical management of osteosarcoma in dogs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40575-021-00100-7.

Prevalence of commonly diagnosed disorders in UK dogs under primary veterinary care: results and applications

Background

Although dogs are a commonly owned companion animal in the UK, the species experiences many health problems that are predictable from demographic information. This study aimed to use anonymised veterinary clinical data from the VetCompass™ Programme to report the frequency of common disorders of dogs under primary veterinary care in the UK during 2016 and to explore effects associated with age, sex and neuter status.

Results

From an available population of 905,543 dogs under veterinary care at 886 veterinary clinics during 2016, the current study included a random sample of 22,333 (2.47 %) dogs from 784 clinics. Prevalence for each disorder was calculated at the most refined level of diagnostic certainty (precise-level precision) and after grouping to a more general level of diagnostic precision (grouped-level precision). The most prevalent precise-level precision disorders recorded were periodontal disease (prevalence 12.52 %, 95 % CI: 12.09–12.97), otitis externa (7.30 %, 95 % CI: 6.97–7.65) and obesity (7.07 %, 95 % CI: 6.74–7.42). The most prevalent grouped-level disorders were dental disorder (14.10 %, 95 % CI: 13.64–14.56), skin disorder (12.58 %, 95 % CI: 12.15–13.02) and enteropathy (10.43 %, 95 % CI: 10.04–10.84). Associations were identified for many common disorders with age, sex and neuter.

Conclusions

The overall findings can assist veterinarians and owners to prioritise preventive care and to understand demographic risk factors in order to facilitate earlier diagnosis of common disorders in dogs. The information on associations with age, sex and neuter status provides additional contextual background to the complexity of disorder occurrence and supports targeted health controls for demographic subsets of dogs.

Development and internal validation of a prediction tool to aid the diagnosis of Cushing's syndrome in dogs attending primary-care practice

BACKGROUND

Novel methods to aid identification of dogs with spontaneous Cushing's syndrome are warranted to optimize case selection for diagnostics, avoid unnecessary testing, and ultimately aid decision-making for veterinarians.

HYPOTHESIS/OBJECTIVES

To develop and internally validate a prediction tool for dogs receiving a diagnosis of Cushing's syndrome using primary-care electronic health records.

ANIMALS

Three hundred and ninety-eight dogs diagnosed with Cushing's syndrome and 541 noncase dogs, tested for but not diagnosed with Cushing's syndrome, from a cohort of 905 544 dogs attending VetCompass participating practices.

METHODS

A cross-sectional study design was performed. A prediction model was developed using multivariable binary logistic regression taking the demography, presenting clinical signs and some routine laboratory results into consideration. Predictive performance of each model was assessed and internally validated through bootstrap resampling. A novel clinical prediction tool was developed from the final model.

RESULTS

The final model included predictor variables sex, age, breed, polydipsia, vomiting, potbelly/hepatomegaly, alopecia, pruritus, alkaline phosphatase, and urine specific gravity. The model demonstrated good discrimination (area under the receiver operating curve [AUROC] = 0.78 [95% CI = 0.75-0.81]; optimism-adjusted AUROC = 0.76) and calibration (C-slope = 0.86). A tool was developed from the model which calculates the predicted likelihood of a dog having Cushing's syndrome from 0% (score = -13) to 96% (score = 10).

CONCLUSIONS AND CLINICAL IMPORTANCE

A tool to predict a diagnosis of Cushing's syndrome at the point of first suspicion in dogs was developed, with good predictive performance. This tool can be used in practice to support decision-making and increase confidence in diagnosis.

Demography and commonly recorded clinical conditions of Chihuahuas under primary veterinary care in the UK in 2016

BACKGROUND

The Chihuahua, the world's smallest dog breed, is a popular breed in the UK today. The VetCompass™ Programme collates de-identified clinical records from primary-care veterinary practices in the UK for epidemiological research. This study aimed to characterise the demography, age at death and common disorders of Chihuahuas under primary veterinary care during 2016 in the UK.

RESULTS

Chihuahuas comprised 11,647/336,865 (3.46%) dogs under veterinary care during 2016. The annual proportional birth rate for Chihuahuas rose from 1.01% in 2005 to 5.35% in 2016. Median adult bodyweight was 3.4 kg (interquartile range [IQR]: 2.7-4.3, range 0.8-9.8).). Median age was 2.8 years (interquartile range [IQR] 1.6-4.9). Median age at death from this young expanding population was 8.2 years (IQR 3.5-12.1). Females (10.2 years) outlived males (6.9 years) (Mann-Whitney U test: P = 0.005). The most common grouped causes of death were heart disease (18.8%, 95% CI: 10.9-29.0), lower respiratory tract disorder (16.3%, 95% CI: 8.9-26.2) and traumatic injury (13.8%, 95% CI: 7.1-23.3). The most common specific disorders were periodontal disease (13.5%, 95% CI: 12.6-14.4), obesity (5.9%, 95% CI: 5.3-6.5), retained deciduous dentition (5.7%, 95% CI: 5.1-6.4), anal sac impaction (4.9%, 95% CI: 4.4-5.5) and aggression (4.2%, 95% CI: 3.7-4.8). Among the 28 most common fine-level disorders, males had statistically (P <  0.005) higher probability than females for 5 disorders (aggression, heart murmur, otitis externa, conjunctivitis and upper respiratory tract infection). There were no disorders with statistically (P <  0.005) higher prevalence in females.

CONCLUSIONS

This study documented rising ownership and a currently youthful population of Chihuahuas in the UK. These results suggest that the Chihuahua is currently undergoing a popularity boom but veterinarians need to be watchful for welfare issues related to impulse purchase of Chihuahua puppies by owners with limited experience of dog care. Periodontal disease, obesity, retained deciduous dentition, anal sac impaction and aggression were identified as common health issues within the breed. The unique veterinary care needs of this popular miniature breed suggest that veterinarians should consider the value of advanced training in anesthesia and dentistry in small-sized dogs.