Ascites will occur in the early stages of cat-to-abdominal transmission. Feline infectious peritonitis virus can cause peritonitis in cats, leading to an abnormal increase in peritoneal permeability and a decrease in its reabsorption capacity. Lymphatic vessel obstruction causes exudative ascites in cats.

Ascites will occur in the early stages of cat-to-abdominal transmission. Feline infectious peritonitis virus can cause peritonitis in cats, leading to an abnormal increase in peritoneal permeability and a decrease in its reabsorption capacity. Lymphatic vessel obstruction causes exudative ascites in cats. At this time, it can be observed that the cat's abdominal girth is enlarged, the spine and ribs on the back are exposed, and the cat is gradually losing weight.

In the early stages of feline abdominal distension, the ascites is usually colorless, transparent or light yellow. The fluid is viscous because it contains a large amount of fibrin clots, which solidify when exposed to air. The ascites contains a large number of mesothelial cells, neutrophils, and macrophages. As ascites continues to increase, it will compress surrounding organs, so early treatment is recommended.