According to statistics collected in 2014 by the Association for Pet Obesity Prevention, it is estimated that more than 50% of dogs in the United States are overweight or obese. Simply put, animals gain weight when they consume more calories than their body requires. Feeding extra dog food, treats, table scraps, human foods, rawhides, and anything else that contains calories can contribute to excess weight gain. A dog is considered overweight when he or she is more than 10% over ideal body weight, and a dog is considered obese when he or she is more than 20% above ideal body weight.
While many overweight and obese dogs are apparently otherwise healthy, others have other noticeable and potentially severe health conditions in addition to being overweight. Overweight dogs frequently have additional health conditions such as arthritis, respiratory problems, or lower urinary tract disease. These conditions may be a result of the excess body weight, or may occur in conjunction with obesity. Considering the management of overweight dogs is largely based on nutritional modification, the presence of other health conditions can complicate diet selection and nutritional management of these dogs.
Lower urinary tract disease is a general term, describing diseases of the bladder and urethra. In dogs, the most common manifestations of lower urinary tract disease are urinary incontinence, urinary tract infections and urinary stones or crystals.The most frequent signs of lower urinary tract disease include:
• Blood in the urine;
• Straining to urinate;
• Urinating small amounts more frequently.
Veterinarians can identify urinary stones and crystals using diagnostic tests such as x-rays or urinalysis.
Urinary stones and crystals are composed of different minerals that bind together in the urine. Typically, crystals form first and then bind together, forming a stone. Urinary stones and crystals can form as spontaneously or as a result of a urinary tract infection. If there is a stone present, management can be nutritional, medical, or surgical, and management depends on the stone type. The most common types of urinary stones in dogs are calcium oxalate and struvite. In cases of struvite urinary stones, nutritional modification combined with antibiotic therapy as needed for concurrent urinary tract infection may be all that is required to treat the stone. Struvite stones can dissolve using a veterinary therapeutic diet designed for struvite dissolution. In cases of emergency urinary obstruction or non-struvite stones such as calcium oxalate, surgery may be required to remove the stone. However, regardless of the chosen method to remove the stone, nutritional modification is often required after surgical removal of or dissolving a stone in order to prevent future formation of urinary stones, as recurrence is common.
If a veterinarian identifies multiple conditions in a dog such as obesity and urinary stones, management can be more complicated than if one of the conditions occurred alone. Nutrition is an important part of management of both conditions – for allowing animals to lose weight safely, to dissolve struvite stones if present, and to help reduce recurrence of all stone types including struvite and calcium oxalate.