Identity

A high-priority, feed-related toxicological disease caused by Ochratoxin A. It specifically targets the proximal convoluted tubules of the kidney, halting protein synthesis and causing severe nephrosis, hyperuricemia, and visceral gout.

Overview

Ochratoxicosis is a severe mycotoxicosis prevalent where grains are stored in damp, cool-to-warm conditions. Ochratoxin A competitively inhibits cellular protein synthesis and stimulates lipid peroxidation, selectively destroying the renal tubular epithelium. This prevents uric acid clearance, leading to hyperuricemia and visceral gout. It also impairs Vitamin D3 activation, compromising skeletal development and eggshell quality. Management involves grain storage moisture control (<13%), targeted mycotoxin binders, and administering urinary acidifiers (ammonium chloride) to dissolve urate deposits.

Structured Facts

Classification

Toxicological > Non-Infectious

Epidemiology

• Prevalence in India: High commercial importance
• Severity: High
• Affected Species: Poultry
• Affected Age: All age groups; growing broilers show high susceptibility
• Transmission: Ingestion of contaminated feed (barley, wheat, maize)
• Seasonality: Associated with damp, cool-to-warm storage conditions
• Mortality: 10% to 40%
• Morbidity: High (10% to 40% clinical; subclinically higher)
• Economic Importance: High (kidney damage, poor eggshell quality)

Clinical Signs

• Early/Intermediate: Severe depression, growth retardation, increased water consumption (polydipsia), watery-white diarrhea (polyuria) causing wet litter
• Advanced: Drop in lay, eggs with blood spots/thin shells. Targets Renal system (Tubules), Skeletal system, and Immune system
• Postmortem Findings: Severely swollen, pale, firm kidneys with prominent white lines (urate crystals in ureters/ducts). Visceral gout (urate crystals on serosal surfaces).

Diagnosis

• Field Diagnosis: Polydipsia, polyuria, swollen pale kidneys
• Laboratory Tests: HPLC or ELISA on feed samples. Histopathology: epithelial necrosis/karyomegaly in renal proximal tubules
• Differential Diagnosis: Infectious Bronchitis (nephrotropic), Calcium-Phosphorus imbalance

Treatment

• Immediate Actions: Remove contaminated feed
• Medicines: Urinary acidifiers: Ammonium chloride (100 to 200 mg/day orally)

Prevention

• Vaccination: None
• Biosecurity: Mitigated by standard Biosecurity Protocols
• Farm Management: Grain storage moisture < 13%; incorporate specific mycotoxin binders capable of adsorbing/bio-transforming OTA

Quantitative Data

• Morbidity Rate: 10% to 40%
• Mortality Rate: 10% to 40%
• Lethal Dose (LD50): 2 to 3 mg/kg of body weight
• Target Moisture Level: < 13%
• Ammonium Chloride Dose: 100 to 200 mg/day

Relationships

• Vaccines: None
• Medicines: Ammonium chloride, Mycotoxin Binders
• Predisposing Relationships: Causes Visceral Gout (hyperuricemia); triggers Cage Fatigue (Vitamin D3/Calcium impairment)