Polycystic kidney disease

This is a common disease in goldfish that causes a slow progressive swelling of the belly over many months or years. In some cases, the fish may swell up so much that they look like they may burst. It is thought to be due to a developmental /genetic abnormality or a parasite that damages the kidneys. Large cysts develop in the kidney which enlarge and occupy a large part of the body cavity. Although it is easily confirmed on an ultrasound scan, there is no treatment for the disease.

Goldfish polycystic kidneys
Goldfish polycystic kidneys

Severely swollen belly is common in fish and although there can be several different causes, polycystic kidneys are common in goldfish

Goldfish polycystic kidneys
Goldfish polycystic kidneys

Side view X-ray showing moderate swelling of the belly and increased distance between the two swim bladder chambers (2 black central areas)

Goldfish polycystic kidneys
Goldfish polycystic kidneys

Post mortem of an affected goldfish showing the swollen kidneys can be more than 10 times their normal size and occupy most of the body cavity

Goldfish polycystic kidneys
Goldfish polycystic kidneys

Severely swollen belly is common in fish and although there can be several different causes, polycystic kidneys are common in goldfish

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