Swelling or Bloating
A healthy dog normally has a trim figure with a waist that can be clearly seen when you look from above and a tuck-up right before the hind legs when you look from the side. If your dog's figure is round, she may just be overweight, or she may have a medical problem. A sudden increase in width is a definite cause for alarm. Bloat, or gastrointestinal volvulus, is a life-threatening condition that happens when a dog's stomach has twisted. Your dog needs to go to the veterinarian immediately, even if it's the middle of the night.
Some owners believe their dog is overweight when actually the abdomen is distended with fluid. Fluid can build up in the abdomen over weeks or days. This may be secondary to a heart condition, cancer, or severe inflammation. Your veterinarian will want to tap your dog's abdomen and take a fluid sample for analysis and possible culture.
Other Reasons for Swelling
Other areas of your dog's body may show swelling as well. Swollen joints can be caused by chronic arthritis or acute infections such as Lyme disease. Cancer may show up as a lump or swelling almost anywhere. These swellings could be benign such as a lipoma or serious such as osteosarcoma, or bone cancer. A swollen nose or muzzle could be caused by a bee sting. As always, it is important to know what's normal for your dog so you can immediately identify any changes. If you're concerned about an unusual swelling, ask your veterinarian to check it out.