# Yorkshire Terriers under primary veterinary care in the UK – demography and disorders

## TL;DR

This study analyzed veterinary records to understand the health and demographics of Yorkshire Terriers in the UK in 2016, finding common disorders and a declining ownership trend.

## Contribution

The study provides the first comprehensive analysis of Yorkshire Terriers' health and longevity using primary-care veterinary data in the UK.

## Key findings

- Periodontal disease was the most common disorder in Yorkshire Terriers, affecting 21.10% of the sample.
- Yorkshire Terriers had a median lifespan of 13.56 years, indicating high longevity.
- Brain and kidney disorders were the leading causes of death in the breed.

## Abstract

The Yorkshire Terrier is a long-established and commonly owned dog breed. This study aimed to explore anonymised primary-care veterinary clinical data from the VetCompass Programme to characterise the demography, common disorders and longevity of the general population of Yorkshire Terriers in the UK in 2016.

Yorkshire Terriers composed 28,032 (3.10%) of the study population of 905,542 dogs under veterinary care in 2016. Annual proportional birth rates decreased in popularity between 2005 and 2016, from 3.54% of all dogs born in 2005 to 2.15% in 2016. The median adult bodyweight was 5.06 kg (IQR 3.81–6.49, range 1.01-15.00). Clinical records from a random sample of 3,308/28,032 (11.80%) Yorkshire Terriers were manually reviewed to extract information on all disorders diagnosed during 2016. The most commonly diagnosed disorders were periodontal disease (21.10%, 95% CI: 19.71–22.49), overgrown nail(s) (6.47%, 95% CI: 5.63–7.31), anal sac impaction (3.99%, 95% CI: 3.32–4.66), overweight/obesity (3.72%, 95% CI: 3.07–4.36) and persistent deciduous teeth (3.57%, 95% CI: 2.94–4.20). Among the 464/3,308 (14.03%) Yorkshire Terriers that died during the study period, the median age at death was 13.56 years (IQR 11.30–15.15, range 0.06–19.08). The most common disorder groups causing death were brain disorders (9.79%, 95% CI: 6.79–12.78) and kidney disorders (8.73%, 95% CI: 5.88–11.58).

The current study identifies a reducing ownership trend for Yorkshire Terriers in the UK. Disorders that are common and appear predisposed in Yorkshire Terriers include periodontal disease, persistent deciduous teeth and patellar luxation. Overall, the Yorkshire Terrier has high longevity, which is suggestive of robust overall health.

The Yorkshire Terrier breed, colloquially known as the Yorkie, was developed and subsequently fixed as a distinct breed in approximately 1865 and was historically very common among the pedigree subset of UK dogs registered with the Kennel Club (KC). However, annual KC registrations suggest that the breed has reduced markedly in popularity more recently. The breed is widely considered to be relatively healthy and long-lived. This study aimed to explore anonymised primary-care veterinary clinical records from the VetCompass Programme to report the demographics, common disorders and longevity of the general population of Yorkshire Terriers in the UK in 2016.

Yorkshire Terriers comprised 28,032 (3.10%) of the 905,542 dogs included in the study. The percentage of all dogs born each year that were Yorkshire Terrier decreased from 3.54% of all dogs born in 2005 to 2.15% in 2016. The average bodyweight of adult Yorkshire Terriers was 5.06 kg.

The veterinary clinical records of a random sample of 3,308/28,032 (11.80%) Yorkshire Terriers were read, and information on all disorders during 2016 was extracted. The most common disorders of Yorkshire Terriers were periodontal (dental) disease (21.10%), overgrown nail(s) (6.47%), anal sac impaction (3.99%), overweight/obesity (3.72%) and retained milk (deciduous) teeth (3.57%).

Among the 464/3,308 (14.03%) Yorkshire Terriers that died during the study period, the average lifespan of Yorkshire Terriers was 13.56 years. The most common reasons for death were brain disorders (9.79%) and kidney disorders (8.73%).

Conclusions.

The current study confirmed declining ownership of Yorkshire Terriers in the UK. Disorders that are common and appear predisposed in Yorkshire Terriers include dental (periodontal) disease, persistent milk (deciduous) teeth and slipping kneecap (patellar luxation). Overall, Yorkshire Terrier has high longevity, which is suggestive of robust overall health.