Environmental
🟡 Moderate
✓ Treatable
Nephrocalcinosis
🦠 CO2 supersaturation in water (>20 mg/L); also associated with excess dietary calcium · Non-infectious
📋 Definition
Deposition of calcium carbonate and calcium phosphate crystals in the kidney tubules of fish exposed to chronically elevated CO2 levels in water.
📊 Key Facts
Causative Agent
CO2 supersaturation in water (>20 mg/L); also associated with excess dietary calcium
Agent Family
Non-infectious
Geographic Range
Worldwide — recirculating aquaculture systems (RAS)
Transmission Routes
Non-infectious
Primary Host
Rainbow Trout, Atlantic Salmon, other salmonids
Vaccine
✗ None / Experimental
🩺 Clinical Signs
Swollen/pale kidney with white chalky deposits; reduced growth; abdominal distension; impaired osmoregulation.
🔬 Symptoms
🔬
White chalky kidney deposits
Renal Chronic
🔬
Swollen pale kidney
Renal Subacute
🔬
Reduced growth
Systemic Chronic
🧪 Diagnosis
Post-mortem (gritty kidney with white crystals), histopathology, measure CO2 in water.
💊 Treatment
Reduce CO2 levels in system water to <10 mg/L. Aeration/degassing.
🛡️ Prevention
ℹ️ Prevention is the most effective strategy for managing this disease in aquaculture and aquarium settings.
Monitor and control CO2 in intensive RAS systems; ensure adequate degassing.