How can you tell if a dog has ascites (fluid in the abdomen)?

A dog’s ascites is mostly hepatic (liver) ascites. Externally, the body keeps wasting while the belly enlarges and sags, swollen like a ball – a clear sign. Early on appetite may be normal or even increased, yet the dog never fattens and shows continued wasting; severe cases add jaundice. Some dogs arch the back with dry coats, then weaken with rapid breathing – at that point it is urgent; take the dog to the vet promptly.