Pathophysiology, Clinical Symptoms, and Nutritional Management of Kidney Swelling and Tracheal Inflammation in Commercial Broilers at Early and Mid-Grower Phases

Abstract: In commercial broiler production, kidney swelling in a striped form and tracheal inflammation are recurrent clinical conditions observed around 5–8 days and 22–25 days of age. These signs correlate with viral and toxin-related etiologies and are often exacerbated by environmental stressors and nutritional imbalances.

1. Introduction
Broiler chickens are genetically selected for rapid growth, which predisposes them to metabolic, infectious, and toxic challenges. Notably, renal pathology and respiratory involvement are critical concerns during the early brooding period and mid-grower phase. Observations of striped renal swelling and tracheal inflammation during these phases often suggest a multifactorial etiology, including nephropathogenic infectious bronchitis virus (NIBV), mycotoxins, and immunosuppressive stress.

2. Clinical Symptoms; 5–8 Days:
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Depression, ruffled feathers
Respiratory distress (mild chirping to gasping)
Pale urates in droppings (renal involvement)
Dehydration signs

22–25 Days:

Sudden drop in feed intake
Tracheal rales, open-mouth breathing
Swollen kidneys with linear striations on postmortem
Tracheal congestion, hemorrhage

3. Postmortem Findings

Kidneys: Enlarged, pale, with striped (striated) pattern – indicative of tubular necrosis or urate deposition.
Trachea: Inflamed mucosa, sometimes with hemorrhage or mucus plugs.
Air sacs: Mild to moderate turbidity, in some cases.

4. Possible Etiologies
4.1 Nephropathogenic Infectious Bronchitis Virus (NIBV)

Affects respiratory tract and renal tissue.
Replicates in renal tubular epithelium causing interstitial nephritis.
Common during early brooding and re-emerges under immunosuppression.

4.2 Mycotoxins (Ochratoxin A, Citrinin, Fumonisin)

Affect renal tubular cells.
Enhance susceptibility to nephropathogenic viruses.
Frequently found in poorly stored corn, rice bran, DDGS.

4.3 Dehydration and Electrolyte Imbalance

Imbalance in sodium and potassium may cause renal swelling and urate accumulation.
Inadequate water intake or high water salinity (Na, Cl, sulfate).

4.4 Secondary Bacterial Infections

Escherichia coli or Mycoplasma gallisepticum can exacerbate tracheitis.

5. Prevention and Biosecurity

Use NIBV vaccine strains (Mass and variants ) via coarse spray or eye drops in hatchery or early brooding phase.
Strict biosecurity and all-in-all-out policy to prevent viral persistence.
Monitor water quality, particularly sodium and sulfate levels (<50 ppm for sodium, <250 ppm for sulfate).
Ensure feed quality, free of mold and fungal toxins using pH-stable toxin binders.

6. Clinical Nutrition and Supportive Therapy

Nutritional Additive	Role	Dosage
Natural Betaine(Hepatron/Betaforte)	Osmoprotectant, supports kidney function and recovery from dehydration	500–1000 ml/1000 L in drinking water for 3–5 days
LiverPro (L-carnitine + Inositol + Betaine)	Supports hepatic and renal detoxification, antioxidant	1 ml/L water for 5 days
Biotox (pH-stable toxin binder)	Binds ochratoxin, citrinin, fumonisin in feed	1–2 kg/ton feed continuously
Electrolyte and Acidifier Blend	Helps maintain acid–base balance, improves renal clearance	1 gm/L for 3 days during stress
Liquivit/Activiton (Vit D3 + E)	Enhances mucosal immunity, reduces inflammation	1 ml/L water for 3–5 days

7. Case-Based Recommendations

5–8 Days: Start Natural Betaine and Liquivit along with Enterococcus faecium probiotic. Avoid nephrotoxic antibiotics like gentamicin unless necessary.
22–25 Days: Reassess feed and water. Provide pH-stable toxin binder, start LiverPro with Natural Betaine for 5–7 days to support kidney and liver. Address any IBV-related recurrence with herbal or supportive antiviral formulations.

8. Conclusion
Renal swelling and tracheal inflammation in commercial broilers around 5–8 and 22–25 days of age represent a classic multifactorial challenge involving viral nephropathies, mycotoxins, and management stressors. Timely vaccination, strict biosecurity, water quality management, and the use of supportive clinical nutrition—especially Natural Betaine, toxin binders, and vitamins—are crucial in maintaining flock health and productivity.

9. References

Cavanagh, D. (2007). Coronavirus avian infectious bronchitis. Veterinary Research, 38(2), 281–297.
Reddy, K. E., et al. (2018). Effects of ochratoxin A on renal function and immune response in poultry: a review. Toxins, 10(9), 394.
Leeson, S., & Summers, J. D. (2009). Commercial Poultry Nutrition. Nottingham University Press.
Wyatt, R. D., & Hamilton, P. B. (1975). Ochratoxicosis in broiler chickens. Poultry Science, 54(5), 1831–1837.
Bozkurt, M., et al. (2012). Effect of dietary betaine and organic acid addition on performance and immune response in broilers. Poultry Science, 91(4), 956–965.