Hyperammonemia Case in an Iceland Pony

A 22 years old castrated male Iceland pony was presented at the Clinic of Vienna Veterinary University due to vague colic symptoms. The blood examination indeed revealed hyperammonemia (Ammonia: 136 μmol/L, normal value for healthy horses: <20 μmol/L). The patient received intravenous fluids aimed at flushing out toxic metabolites. Furthermore, lactulose was given per nasogastric tube. After this therapy, there was short-term improvement for some hours, but the animals again developed serious odd behavior. He was very ataxic and injured itself. Based on the bad prognosis, the owner took the decision to have the mare euthanized. Necropsy revealed cachexia, severe ascites; the liver seemed smaller, felt dense and had an irregular surface. Histopathology showed fibrotic degeneration and necro-sis of the hepacytes, a generalized accumulation of fat, medium degree of edema and in all liver lobes. The diagnosis confirmed hepatocites encephalopathy caused by hepatic cirrhosis.
Anahtar Kelimeler:

Colic, horse, hyperammonemia

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