Sour Crop (Candidal Ingluvitis) in Chickens: Symptoms, Causes and Treatment
Sour crop in chickens is delayed crop emptying with yeast or bacterial overgrowth, often involving Candida after diet disruption, antibiotics, or another crop disorder. The crop remains soft and fluid-filled in the morning, and the bird may have sour breath, poor appetite, and weight loss. Treatment corrects the underlying stasis, restores hydration and gut flora, and uses veterinary antifungal medication when candidiasis is confirmed.
Veterinarian Reviewed
FlockVet Veterinary Editorial Team· Reviewed January 2026
At a Glance
- Urgency
- Moderate
- Contagious
- No
- Affects Humans
- No
- Key Symptoms
- soft, squishy, pendulous crop that does not empty overnight, sour or yeasty smell from the beak, weight loss
- Prognosis
- Excellent with proper treatment. Most cases resolve within 2-3 weeks. Recurrence is common if dietary cause is not corrected.
📑 On This Pagetap to expand
🔍What Are the Symptoms of Sour Crop (Candidal Ingluvitis)?
- ●Soft, squishy, pendulous crop that does not empty overnight
- ●Sour or yeasty smell from the beak
- ●Weight loss
- ●Diarrhea
- ●Lethargy
- ●White plaques or cheesy material in mouth or throat
- ●Reduced appetite
- ●Fluffed feathers
🧬What Causes Sour Crop (Candidal Ingluvitis) in Chickens?
Sour crop is caused by Candida albicans overgrowth in the crop, triggered by disruption of normal microbial balance:
- Antibiotic use - the most common cause. Antibiotics destroy beneficial bacteria, leaving the environment open for Candida colonization
- High-sugar, high-carbohydrate diet - scratch grains, bread, fruit, cracked corn feed yeast directly
- Moldy feed - pre-existing fungal contamination
- Impaired crop motility - from pendulous crop or previous impaction
- Vitamin A deficiency - weakens mucosal defense
- Stress - suppresses immune response, allows opportunistic overgrowth
🔬How Is Sour Crop (Candidal Ingluvitis) Diagnosed?
Distinguish from impacted crop by feel:
- Sour crop: Soft, squishy, balloon-like, foul sour smell, may gurgle when pressed gently
- Impacted crop: Hard, firm, packed material, no distinctive smell
White plaques in the mouth confirm Candida involvement and indicate systemic spread.
💊How Is Sour Crop (Candidal Ingluvitis) Treated?
Step 1: Withhold feed for 12-24 hours (water allowed). This rests the crop and reduces fermentation substrate.
Antifungal treatment:
- Nystatin (prescription) mixed in feed at 100,000 IU/bird/day for 7-14 days - most effective for crop and GI candidiasis
- Fluconazole 5-10mg/kg orally for severe cases
- Miconazole cream applied to mouth plaques if present
Crop emptying (severe cases only, with experience): Gently massage crop while bird is tilted slightly forward to encourage emptying. Only attempt if crop is very full and not showing signs of improvement. Risk of aspiration.
Apple cider vinegar for sour crop
For a mild case, offer raw, unfiltered apple cider vinegar with the mother at 1 tablespoon per gallon of drinking water for several days, using a nonmetal waterer and refreshing it daily. It may support crop acidity but does not remove an obstruction or replace antifungal treatment. Stop if the bird drinks less, and seek veterinary care for weakness, aspiration risk, or a crop that remains enlarged.
Natural & Integrative Care for Sour Crop (Candidal Ingluvitis)
Sour crop is a dysbiosis condition that responds very well to ACV, probiotics, and diet correction. Natural care addresses the root cause better than antifungals alone.
Sour crop responds excellently to integrative care in mild to moderate cases - often without pharmaceutical antifungals.
Raw apple cider vinegar (primary intervention): 1 tablespoon per gallon, daily throughout treatment. ACV directly acidifies the crop environment, making it hostile to Candida. Use as sole water source. Results typically visible within 3-5 days.
Plain yogurt with live cultures: 1 teaspoon per bird per day administered directly. Lactobacillus species compete with Candida for colonization sites. This is both treatment and prevention.
Oregano oil (3 drops per gallon water): Carvacrol has direct antifungal activity against Candida species. Use 5x per week through treatment.
Dietary correction (essential): Eliminate all sugars and fermentable carbohydrates immediately. No scratch grains, bread, fruit, or treats for minimum 2 weeks. Feed only high-quality pellets and leafy greens.
Coconut oil: 1/4 teaspoon per bird per day in feed. Contains caprylic acid with documented anti-Candida properties. Also supports crop motility.
Fermented feed: Once acute phase resolves, transitioning to fermented feed maintains beneficial microbial balance and prevents recurrence.
🛡️How Can Sour Crop (Candidal Ingluvitis) Be Prevented?
- ACV in water 3x weekly as maintenance
- Probiotics or plain yogurt after every antibiotic course
- Limit scratch grains to less than 10% of diet
- Never feed moldy or spoiled feed
- Fermented feed 3-4x weekly supports long-term crop microbiome health
📞When Should I Call a Vet for Sour Crop (Candidal Ingluvitis)?
Call a vet if:
- White plaques are extensive in the mouth and throat (systemic Candida)
- Bird is not improving after 7 days of ACV and probiotic treatment
- Bird is losing significant weight or refusing to eat
❓Sour Crop (Candidal Ingluvitis): Frequently Asked Questions
How do you treat sour crop in chickens?
Withhold food for 24 hours while maintaining water access. Add 1 tablespoon of raw apple cider vinegar per gallon of drinking water to acidify the gut environment. Offer plain yogurt with live cultures or a probiotic supplement to restore beneficial bacteria. For severe cases with a very large, fluid-filled crop, veterinary drainage may be needed.
How do you cure sour crop in chickens?
Sour crop resolves in most cases with 3-7 days of treatment: fasting, ACV water, probiotics, and antifungal medication for confirmed fungal cases (nystatin or miconazole). Remove all access to moldy feed and high-sugar treats. Eliminate scratch and cracked corn during recovery. Most hens return to normal within a week.
What is sour crop in chickens?
Sour crop is a fungal or bacterial infection of the crop - the storage pouch in a chicken's throat where food waits before digestion. When the crop's normal microbial balance is disrupted, Candida yeast overgrows, producing a foul-smelling, fluid-filled crop. It feels like a water balloon on the chest.
What causes sour crop in chickens?
Sour crop is most commonly caused by antibiotic use (which kills beneficial gut bacteria), a high-sugar or high-carbohydrate diet (scratch, bread, fruit), moldy feed, or a compromised immune system. Anything that disrupts the crop's normal microbial balance creates an opportunity for Candida overgrowth.
Does apple cider vinegar help sour crop in chickens?
Yes. Raw, unfiltered apple cider vinegar at 1 tablespoon per gallon of water acidifies the crop environment, making it inhospitable to Candida yeast. Use only raw ACV with the mother - not distilled white vinegar. ACV works best for mild to moderate cases and as a weekly preventive measure.
📋Key Points
- ✓Sour crop is caused by Candida albicans overgrowth in the crop, triggered by disruption of normal microbial balance: Antibiotic use - the most common cause.
- ✓Key symptoms: soft, squishy, pendulous crop that does not empty overnight, sour or yeasty smell from the beak, weight loss, diarrhea.
- ✓Excellent with proper treatment. Most cases resolve within 2-3 weeks. Recurrence is common if dietary cause is not corrected.
🔗Related
Related Conditions
Medications
Natural Remedies & Supplements
📚Sources & References
- 1.Crop Disorders in Poultry. Merck Veterinary Manual. 2024
- 2.Common Management-Related Problems in Backyard Poultry. Merck Veterinary Manual. 2024
- 3.Management of Backyard Poultry. Merck Veterinary Manual. 2024