Obesity is a modern day epidemic in companion animals and is one of the most common disorders affecting dogs. Veterinary professionals are all too aware of the welfare consequences of obesity in dogs, from associations with shortened lifespan, reduced quality of life and a higher incidence of important conditions including osteoarthritis, diabetes mellitus and certain types of neoplasia. There has been a recent call for the veterinary profession to formally recognise companion animal obesity as a disease, which has support from many veterinary healthcare professional organisations globally.
The use of bodyweight itself and our interpretation of bodyweight — body condition scoring (BCS) — are recommended to classify dogs as underweight, a healthy weight, overweight or obese. However, despite BCS being recommended as routine during veterinary examinations, recording of BCS in veterinary clinical notes is not common. Prevalence estimates for overweight status in dogs have varied widely, with estimates based on veterinary clinical records much lower than those based on planned prospective studies, almost certainly reflecting underreporting of overweight status in veterinary notes.
Risk factors for overweight status in dogs, such as breed, age, and neuter status, have been explored previously in smaller datasets, but never using a ‘big data’ approach. Therefore, we decided to harness the power of VetCompass ‘big data’ to robustly answer the question about the frequency and risk factors for overweight status in dogs, with special emphasis on breed associations. The study included 22 333 dogs whose health was followed for a year (2016) to identify 1580 (7.1%) recorded as overweight.
Eight breeds had increased risk of overweight status compared with crossbred dogs: Pug (3.12 times the risk), Beagle (x 2.67), Golden Retriever (x 2.58), English Springer Spaniel (x 1.98), Border Terrier (x 1.72), Labrador Retriever (x 1.70), Cavalier King Charles Spaniel (x 1.50) and Cocker Spaniel (x 1.32). Conversely, two breeds showed reduced risk: Shih-tzu (x 0.53) and German Shepherd Dog (x 0.55). Where breed increases risk of a problem, it means genes are likely to be at least in part to blame. Previous work by Dr Eleanor Raffan (study co-author) and colleagues suggests that genetics drives a high appetite in some breeds. Therefore, owners of food-obsessed dogs have to work much harder to keep their dogs at a healthy weight.
As well as showing that specific breeds were at differing risk, the study also highlighted that being neutered and middle-aged were additionally associated with increasing chances of dogs being overweight. Specifically, dogs aged 6 to <9 (years) had the highest risk of overweight status (x 2.99) compared with dogs <3, and neutered males had the highest risk (x 1.90) compared with entire females.
This new study estimated the prevalence of dogs under primary veterinary care that were recorded as overweight at 7.1%, although the true proportion is likely to be much higher. Regular weight recording in all dogs would provide useful baseline data and allow early identification of even modest weight changes, which may in turn increase recording of overweight status.
Veterinary nurses can play a key role in turning the tide on the obesity epidemic. Diet and exercise should be key parts of the discussions when an owner acquires a puppy and should be re-assessed throughout the dog's life. Through regular bodyweight and BCS recording from puppyhood, owners can be alerted earlier to any problematic change. In addition, veterinary nurses could show owners how to monitor their dog's BCS at home, enabling owners to play a more active preventative role. This may be especially important for those dogs identified at ‘high risk’ in our study. If a dog is already overweight, ‘weight clinics’ are a fantastic way to get owners engaged with their dog's weight loss. Open dialogue between veterinary professionals and owners is key; obesity is the enemy that veterinary professionals and owners can work together to defeat.
