Common Signs and Effects
Dogs and cats with lead poisoning most commonly show neurological and gastrointestinal signs. They may have loss of appetite, behavior changes, tremors and seizures. Any of these signs should spark a call to your veterinarian. Chronic lead poisoning is more rare, but it can cause signs that include abdominal discomfort, vomiting, diarrhea, lethargy, weight loss, intermittent seizures and megaesophagus (which is a loss of muscle tone in the esophagus leading to dilation) in cats.
Lead interferes with multiple body systems. It causes cell death and brain function impairment. Lead is especially toxic to the fetus and young animals, as it inhibits brain development. It also affects red blood cells, causing anemia (which is when there are too few red blood cells in the blood)
The diagnosis of lead poisoning is made by measuring whole blood lead levels. While the ideal blood lead level is zero, in most species, blood lead levels above 0.3-0.35 ppm (30-35 ug/dl) indicate significant lead exposure. Visually, lead objects can appear on X-rays and can be found in the gastrointestinal tract or, less commonly, as embedded lead projectiles, such as bullets and pellets, in the pet’s body.
Resource: http://www.vetstreet.com/our-pet-experts/lead-poisoning-still-a-concern-for-pets