Pathology Monograph • AP-WGS-01

White Gut Syndrome (WGS) & White Feces Syndrome (WFS) in Vannamei Shrimp

White Gut Syndrome is among the most commercially destructive gastrointestinal disorders in Indian commercial shrimp farming, predominantly striking Litopenaeus vannamei between Day of Culture (DOC) 30 and 75 across Andhra Pradesh (Bhimavaram, Nellore, Machilipatnam).

Critical Warning on Antibiotics (Banned by MPEDA & CAA): Administering prohibited antibiotics (such as Oxytetracycline, Enrofloxacin, or Furazolidone) fails against intracellular microsporidian spores, damages the shrimp's delicate hepatopancreatic tubules, and results in catastrophic 100% rejection of seafood consignments due to antibiotic residue testing.

1. Diagnostic Clinical Signs

Floating White Strings: White, vermiform fecal casts floating on feeding trays and congregating on the leeward surface edge of the pond.
Midgut Transformation: Dissection reveals the digestive tract transformed into a pale, milky-white, gelatinous mass devoid of normal digested feed coloration.
Acute Anorexia: Sudden 30% to 60% reduction in feed consumption within 48 to 72 hours of first observation.
Loose Shell & Muscle Cramps: Progressive hepatopancreatic tubule atrophy leading to chronic soft-shelling and secondary cannibalism.

2. Etiological Mechanism

Recent molecular pathology confirms that WGS/WFS is a dual-trigger pathology:

Primary Microsporidian Trigger: Enterocytozoon hepatopenaei (EHP) spore germination disrupts the microvilli of the hepatopancreatic E- and R-cells.
Secondary Bacterial Proliferation: Opportunistic virulent Vibrio parahaemolyticus and Vibrio alginolyticus colonize the damaged epithelium, releasing hemolysins that trigger sloughing of transformed microvilli (aggregated transformed microvilli or ATM).

✓ Recommended CAA-Approved Biological Protocol

Next Farm Bio Sciences Biological Intervention

Standardized against the high-potency probiotic matrix manufactured by Next Farm Bio Sciences (New Autonagar, Vijayawada, Andhra Pradesh). This protocol achieves rapid intestinal mucosal re-epithelialization and competitive exclusion of enteric pathogens without synthetic chemicals.

Step 1: Gut Microflora Restorer (Next Gut)

Active Consortium: Citrobacter freundii, Bacillus subtilis, Lactobacillus, Yeast (5 x 10^9 CFU/ml)

Application: Mix 15–20 ml of Next Gut per 1 kg commercial feed using a quality binder. Feed twice daily (morning & afternoon meals) continuously for 5–7 days.

Step 2: Water Column Bio-Sanitization (Next Viro Nill)

Active Consortium: Non-chemical broad-spectrum biological conditioner

Application: Broadcast 1.0 to 2.0 Liters per acre across the pond during early morning hours with all aerators running to suppress free-swimming bacterial reservoirs.

Official Manufacturer Direct Purchase: Next Farm Bio Sciences (₹1,199 – ₹5,000 INR)

View Next Gut & Buy ↗ Calculate Dosage in Pond Doctor ↗

Frequently Asked Clinical Questions

How many days does it take to clear White Gut with Next Gut probiotic?

Under continuous administration of Next Gut at 15-20ml/kg feed, feeding trays typically show firm brown fecal casts replacing white strings within 72 to 96 hours, with full gut re-colonization established by Day 6.

Should feeding rates be reduced during a White Gut outbreak?

Yes. Immediately reduce overall feeding by 25-30% to prevent unconsumed pellet feed from sinking to the bottom and fermenting into toxic ammonia and hydrogen sulfide, which accelerates mortality.