Canine Nutrition and Obesity

Original Editor - Oyemi Sillo Top Contributors - Oyemi Sillo, Tarina van der Stockt and Jess Bell

Introduction[edit | edit source]

Obesity is a condition in which the body accumulates excessive amounts of adipose tissue as a result of a positive energy balance that could be due to either a surplus in energy intake or a deficit in energy expenditure. Obesity is the most common disorder of nutrition in companion animals. The incidence of obesity in dogs is increasing, with studies finding that 22%-40% of dogs in various parts of the world are overweight.[1] As with humans, the prevalence of obesity in dogs is on the rise in many countries. An Australian study found that 33.5% of dogs were overweight and 7.6% were obese,[2] and a 2018 survey in the USA found that 55.8% of dogs were overweight or obese.[3]

The following cut-offs have been suggested for classifying obesity in dogs:[1]

  • Overweight = >15% above ‘optimal bodyweight’
  • Obese = >30% above ‘optimal bodyweight’

Risk Factors[edit | edit source]

Risk factors for obesity include:[2]

  • Higher energy intake than energy expenditure
  • Hypothyroidism
  • Hyperadrenocorticism
  • Certain pharmaceuticals e.g. Cortisone, anticonvulsants (can increase hunger in dogs)
  • Genetics – some breeds of dogs have a higher tendency to be obese
  • Neutering – the correlation between neutering and obesity is unclear, but studies show that neutered male dogs have a higher risk of obesity[4]
  • Gender – female dogs are more likely to be obese
  • Behavioural factors e.g. reduced physical activity
  • Dietary habits e.g. high number of meals and snacks, using food as a reward

Pathology[edit | edit source]

Some consequences of obesity in dogs are:[1][5]

  • Orthopaedic disease e.g. osteoarthritis
  • Cardiorespiratory disorders e.g. hypertension, respiratory difficulties, exercise intolerance
  • Metabolic abnormalities
  • Endocrinopathies
  • Urogenital disorders
  • Neoplasia
  • Decreased immune function
  • Functional limitations e.g. heat intolerance or heat stroke


Canine obesity has been linked to dyslipidaemia, mild hypertension, and insulin resistance.[6] Insulin resistance causes the body tissues to lose the ability to respond normally to insulin, resulting in increased secretion of insulin from the pancreas (hyperinsulinemia). This is associated with cardiovascular, renal, liver, and other diseases, as well as decreased lifespan. Obesity, particularly visceral obesity, predisposes dogs to develop insulin resistance. A study found that visceral fat with minimal increase in dogs’ body weight resulted in increased fasting insulin and hepatic insulin resistance. Obesity and insulin resistance are associated with systemic inflammation and increased oxidative stress.[7]

Evaluation[edit | edit source]

Measuring obesity is typically done by determining the body composition – the proportion of fat mass and lean body mass in the body. There are a number of methods for measuring body composition in dogs, however, none is perfectly accurate or precise. The most common quantitative measurements are morphometry (Body Condition Score and Dimensional Evaluations) and body weight measurement.[1]

Body Condition Scoring (BCS) is a visual and manual assessment of an animal’s body composition. This widely accepted clinical assessment tool is subjective, but it has been found that it can estimate body fat and is supported by dual-energy X-ray absorptiometry and deuterium oxide.[8] BCS is evaluated by observation and palpation of the animal’s ribs, abdomen, waistline, and spine to assesses subcutaneous fat, abdominal fat, and superficial musculature. While there are several BCS scales available, the 9-point scale is most commonly used.

In the 9-point scale:[9]

  • A score of 1-3 indicates that the dog is underweight - its ribs, vertebrae, and pelvic bones are easily seen, no fat is felt on the bones, and some loss of muscle mass might be observed
  • A score of 4 or 5 indicates that the dog has a healthy body composition - its ribs are easily felt, its waist is easily observed behind the ribs when viewed from above, and an abdominal tuck is evident when viewed from the side
  • A score of 6 or 7 indicates that the dog is overweight - its ribs are difficult to feel beneath the fat cover, fat deposits are seen over its back and the base of its tail, its waist is not so obvious behind the ribs when viewed from above, and no abdominal tuck is seen in profile
  • A score of 8 or 9 indicates that the dog is obese - its ribs cannot be felt beneath the fat cover, massive fat deposits are seen over its back and the base of its tail, no waist can be observed behind the ribs when viewed from above, and a distended abdomen is evident


[10]

Dimensional Evaluation combines various measures of stature to determine body fat percentage. This system of measurement comprises of:[1]

  1. Measuring a first body dimension that has a high correlation with fat mass – the circumference of the ribcage taken at the ninth rib
  2. Measuring a second body dimension that has a high correlation with lean body mass – the distance from the centre of the patella to the calcaneus (Limb Index Measurement - LIM) of the left hind limb
  3. Inserting the values from 1 and 2 into the calculation: Percentage body fat = [{(ribcage/0.7067)-LIM}/0.9156] – LIM

All measurements are made in centimetres and are taken with the animal standing, all four limbs perpendicular to the ground and head upright. This method has been validated by x-ray absorptiometry (p<0.0001). Due to the significant differences between breeds of dogs, this method of measuring body composition is better suited to cats.

Management / Interventions[edit | edit source]

Treatment of canine obesity has primarily been through dietary and lifestyle management to reduce the causes of obesity and promote a healthier body weight.[1] Dietary strategies for treating obesity in dogs include restricting fat and overall calorie content of food, supplementation with protein and micronutrients, higher fibre intake, portion control, having fewer meals or snacks,[1] The most effective diets focus on reducing signs of hunger in order to decrease a dog's begging behaviour and encourage adherence. This is usually accomplished by changing the macronutrient content of a diet.[11] Increasing physical activity is a major lifestyle change in the management of obesity, and it not only promotes loss of body fat but also preserves lean muscle mass and reduces rebound weight gain. Exercise programmes must be tailored to the needs of individual animals. Lead walking, treadmill walking, swimming, and hydrotherapy are suitable activities for dogs.[1] Dietary and lifestyle management strategies are highly dependent on owner compliance, and can thus be sometimes ineffective.[12] Drug-based management of obesity using Dirlotapide, which decreases appetite and fat absorption, can also be used as an adjunct to the traditional obesity management methods.[12]

Proper Nutrition[edit | edit source]

Dogs require a diet that provides them with all essential nutrients in the right quantities and proportions in order to maintain optimal health. These essential nutrients are amino acids from protein, fatty acids, carbohydrates, vitamins, minerals, and water. Dogs thrive on a varied diet that includes meat, bones, organs, fruits and vegetables. Dogs are preferential carnivores, unlike cats who are obligatory carnivores.[13]

The daily recommended allowance of protein for puppies is 56g, while 25g is recommended for adult dogs. For fats, 21g for puppies and 14g for adult dogs is recommended daily. Animal protein contains essential acids that are closest to those that dogs need, and are thus the ideal source of protein. The quality of protein is determined by the balance of essential amino acids it contains. Grains also contain essential amino acids but in much lower quantities. Because meat is so much more expensive, pet food manufacturers will often use grains as the source of protein and add in the necessary amino acids. Fats from animals sources and seeds contain essential fatty acids that help maintain cell structure and function. Omega-6 is an essential fatty acid that supplies linoleic acid to prevent skin and coat problems. Omega-3 is an essential fatty acid that supplies alpha-linolenic acid (ALA) which is converted to Docosahexaenoic acid (DHA) which is vital. The balance or ratio between the fatty acids is important because too much Omega-6 may inhibit the conversion of ALA or DHA. Meat, eggs, fish, and nuts are all good sources of fat for dogs. Dogs need a daily intake of vitamins (both water-soluble and fat-soluble vitamins) and minerals at low concentrations. Among the most important minerals are calcium and phosphorus needed for milk production, growth and bone formation. In the wild, dogs get this from bones and organs of prey, and pet food manufacturers use by-products, bone meal and calcium phosphates or carbonates.[13]

Caloric intake depends on the dog’s age, weight, level of activity, and health status. Up to 50% of an adult dog’s daily diet could be from carbohydrate, with 2.5-4.5% of this from fibre. Fats should make up at least 5.5% of the diet and proteins should contribute a minimum of 10%. Adult dogs should eat one or two meals daily, while puppies require two to three daily meals.[13]

Resources[edit | edit source]

Body Condition Score

References[edit | edit source]

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 German AJ. The growing problem of obesity in dogs and cats. J Nutr. 2006 Jul;136(7 Suppl):1940S-1946S. doi: 10.1093/jn/136.7.1940S. PMID: 16772464.
  2. 2.0 2.1 McGreevy PD, Thomson PC, Pride C, Fawcett A, Grassi T, Jones B. Prevalence of obesity in dogs examined by Australian veterinary practices and the risk factors involved. Vet Rec. 2005 May 28;156(22):695-702. doi: 10.1136/vr.156.22.695. PMID: 15923551.
  3. Association for Pet Obesity Prevention. 2018 Pet Obesity Survey Results. Available from: https://petobesityprevention.org/2018 (accessed 24 April 2021).
  4. Bjørnvad CR, Gloor S, Johansen SS, Sandøe P, Lund TB. Neutering increases the risk of obesity in male dogs but not in bitches - A cross-sectional study of dog- and owner-related risk factors for obesity in Danish companion dogs. Prev Vet Med. 2019 Oct 1;170:104730. doi: 10.1016/j.prevetmed.2019.104730. Epub 2019 Jul 11. PMID: 31421500.
  5. Laflamme DP. Companion Animals Symposium: Obesity in dogs and cats: What is wrong with being fat? J Anim Sci. 2012 May;90(5):1653-62. doi: 10.2527/jas.2011-4571. Epub 2011 Oct 7. Erratum in: J Anim Sci. 2012 Jul;90(7):2424. PMID: 21984724.
  6. Tvarijonaviciute A, Ceron JJ, Holden SL, Cuthbertson DJ, Biourge V, Morris PJ, German AJ. Obesity-related metabolic dysfunction in dogs: a comparison with human metabolic syndrome. BMC Vet Res. 2012 Aug 28;8:147. doi: 10.1186/1746-6148-8-147. PMID: 22929809; PMCID: PMC3514388.
  7. Colliard L, Ancel J, Benet JJ, Paragon BM, Blanchard G. Risk factors for obesity in dogs in France. J Nutr. 2006 Jul;136(7 Suppl):1951S-1954S. doi: 10.1093/jn/136.7.1951S. PMID: 16772466.
  8. Chun JL, Bang HT, Ji SY, Jeong JY, Kim M, Kim B, Lee SD, Lee YK, Reddy KE, Kim KH. A simple method to evaluate body condition score to maintain the optimal body weight in dogs. J Anim Sci Technol. 2019 Nov;61(6):366-370. doi: 10.5187/jast.2019.61.6.366. Epub 2019 Nov 30. PMID: 31844547; PMCID: PMC6906133.
  9. American Animal Hospital Association. AAHA Guidelines: BCS and MCS. Available from: https://www.aaha.org/aaha-guidelines/nutritional-assessment-configuration/bcs-and-mcs/ (accessed 24 April 2021).
  10. Royal Cannin UK. Body Condition Score your DOG. Available from: http://www.youtube.com/watch?v=r7lHRRbmpBQ
  11. German AJ. Weight management in obese pets: the tailoring concept and how it can improve results. Acta Vet Scand. 2016 Oct 20;58(Suppl 1):57. doi: 10.1186/s13028-016-0238-z. PMID: 27766974; PMCID: PMC5073926.
  12. 12.0 12.1 Gossellin J, Wren JA, Sunderland SJ. Canine obesity: an overview. J Vet Pharmacol Ther. 2007 Aug;30 Suppl 1:1-10. doi: 10.1111/j.1365-2885.2007.00863.x. PMID: 17567509.
  13. 13.0 13.1 13.2 National Research Council. Nutrient Requirements of Dogs and Cats. Washington, DC: The National Academies Press, 2006. https://doi.org/10.17226/10668.