Background Canine obesity is the cause of several health issues, and may predispose other diseases, such as orthopaedic disorders, endocrinopathies, metabolic abnormalities and cardiorespiratory disease which can lead to a decreased quality of life and reduced lifespan. Dog are considered overweight when their body weight is ≥15% above their ideal body weight, and as obese when their body weight exceeds 30% of optimal. Prevalence of canine obesity is estimated to be around 5%–20%, and up to 30%–40% when all overweight dogs are considered. Treatment is based on weight loss programmes, focused on caloric restriction associated with exercise. However, success rate of treatment is low. Objectives The aim of this study was to investigate the reasons for weight loss failure of obese dogs during treatment with low‐calorie diets. Methods Records of obese dogs undergoing weight loss programmes between May 2014 and May 2017, assessed by a team specialized in veterinary nutrition, were retrospectively evaluated. Dogs were classified according to weekly weight loss rate (WWLR) (<1%, between 1% and 2%, and more than 2%) and owner compliance with a dietary prescription and physical activity recommendations. Results The mean WWLR was not satisfactory (<1%) in 64.4% ( n = 47/73) of dogs. Regarding owner compliance with the dietary prescription, 44.7% ( n = 21/47) of owners did not follow diet prescriptions and physical activity recommendations for their dogs. There was a significant association ( p = .01) between compliance of owners and satisfactory weight loss rate; however, there was no association between weight loss success, diet composition sex, reproductive status, age of the dogs and their physical activity ( p ≥ .05). Conclusions Non‐compliance represents a great challenge in the treatment of canine obesity, and may be of more importance than other aspects.

Canine obesity is associated with genetic, environmental, and behavioural factors, with the latter including both the behaviour of the dog and the owner. Knowledge about owner perception of canine obesity and its treatment can inform the development of new strategies to help prevent and manage this disease. Therefore, the aim of this study was to evaluate the opinions of dog owners regarding canine obesity and weight management. Dog owners residing in the city of Sao Paulo (Brazil) completed a questionnaire, either at home or in the waiting rooms of 3 veterinary hospitals. Owners determined their dog's body condition score (BCS), and this was compared with BCS determined by a veterinarian. Questionnaire findings from dogs that were in overweight (BCS 6-7/9) or obese (BCS (8-9/9) condition were compared with those in ideal weight (4-5/9) using chi-square tests and odds ratios. A total of 926 dogs were included, of which 480 (52%), 317 (34%) and 129 (14%) were in ideal, overweight and obese condition, respectively. Many owners underestimated their dog's weight status, with the proportion increasing as the dog's weight status increased (ideal 60/480, 13%; overweight 174/317, 55%; obese 88/129, 68%; P<0.001). Although most owners (890/926, 96%) believed that canine obesity could pose health risks, the proportion that disagreed increased as weight status increased (ideal 12/480, 2%; overweight 14/317, 4%; 10/ 129, 8%; P = 0.006). Finally, although most owners (880/926, 95%) stated that they would let their dog undergo weight management, only a minority (182/926; 20%) believed that a trained professional was needed, and they had various misperceptions including potential cost and what the strategies that would be effective. Based on the findings of this study, it would be advisable for veterinarians to spend time addressing these misperceptions, in the hope of both improving awareness of obesity and the outcomes of weight management.