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Obesity in dogs is a major health concern. Recent studies suggest that its prevalence is steadily increasing globally. A dog is obese when it weighs more than 20% of its ideal weight. Vets use the body condition score (BCS) to determine obesity in dogs. A BCS of 4-5 is ideal, while 6-9 is overweight.

Obesity can have detrimental health effects such as diabetes, osteoarthritis, cardiorespiratory disease, and urinary tract disorders, which can shorten your dog’s lifespan. Common symptoms of obesity in dogs may include weight gain, excess body fat, difficulty in breathing, lethargy, fatigue, and an inability or unwillingness to exercise.

Several underlying causes can lead to obesity, such as the following:

    • Poor nutrition – Proper nutrition helps maintain a healthy lifestyle in dogs. The primary reasons for obesity are overeating and eating high-calorie meals. Reports show that dogs fed once a day are more prone to developing obesity than dogs fed small portions at regular intervals during the day. Researchers also report that small portions consumed frequently during the day improve digestion.
    • Physical inactivity – Dogs with little outdoor exercise or physical activity tend to gain weight gradually and may become obese in their middle age.
    • Breed – Genetics play a fundamental part in your dog’s tendency to gain weight. Certain breeds gain weight faster than others because they are less active, their metabolism is slower, or their appetites are different. Breeds more prone to obesity include American Cocker Spaniels, Basset Hounds, Beagles, Cairn Terriers, Cavalier King Charles Spaniels, Dachshunds, Labrador Retrievers, Norwegian Elkhounds, Rough Collies, and Shetland Sheepdogs.
    • Age and gender – The incidence of obesity in dogs increases as they age. As the metabolism slows, fat tissue accumulates, heightening the risk of obesity. Female dogs are more prone to obesity than male dogs, with at least 60% of obese dogs being females.
    • Neutering – Spaying or neutering is a common risk factor associated with weight gain and obesity in dogs. Loss of sex hormones after neutering reduces the metabolism, causing an imbalance between energy in and energy out, leading to fat accumulation and subsequent weight gain. Consequently, neutered dogs generally require fewer calories and more physical activity to maintain a healthy weight. Reports indicate that if you reduce your neutered dog’s food intake by one-third, increase their exercise, or do both, you can prevent weight gain. It is important to note that the risk of obesity following neutering also depends on the breed and sex of the dog.
    • Medications – Certain medications can cause obesity in dogs. For instance, some seizure treatments and steroid hormones can induce an abnormal hunger response, leading to increased food consumption, fat deposition, and weight gain.

Like humans, obesity in dogs can have serious health effects. Physical, environmental, and hormonal factors can predispose dogs to obesity. However, you can prevent your dog from becoming obese by maintaining a healthier lifestyle. A well-defined exercise routine and balanced, well-proportioned diet can help control your dog’s weight. It’s also a good idea to take your dog for regular checkups with your vet to ensure your dog is at a healthy weight.

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Last Updated: June 14, 2022

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