Why Is My Chicken's Crop Squishy and Sour-smelling? (Sour Crop)
A balloon-squishy crop with sour breath is a yeast overgrowth in stalled crop contents — treatable with patience, worsened by the upside-down folk remedy.
Most likely causes
Crop yeast overgrowth (sour crop)
What points to it: Morning crop full but liquid/squishy, foul sour smell at the beak, sometimes fluid burps when she lowers her head; appetite off.
What to do: Withhold treats and sugary anything; water yes. Feed sparse and simple (a little plain feed, scrambled egg). The keeper standard: copper sulfate or acidified water per experienced guidance, or vet-dispensed nystatin — nystatin is the clean, effective answer where a vet is available. Gentle massage, upright bird, several days of patience.
The underlying stall
What points to it: Sour crop is usually SECONDARY — something slowed the crop first: partial impaction, long fibers, illness elsewhere, or post-antibiotic flora crash.
What to do: Hunt the primary cause with the impacted-crop checklist and the lethargic-bird exam; recurrent sour crop especially means something upstream is wrong.
Check these first
Morning crop check tells the story; smell the beak. Review the last week: antibiotics, long grass, moldy anything, a molting stressed bird? Check for a pendulous crop (permanently stretched — manageable with feeding tricks but not curable).
When it's probably nothing
A big soft crop right after heavy drinking on a hot day can feel alarming and resolve by morning — recheck at dawn before treating.
This guide is experienced-keeper guidance, not veterinary care. When a bird is crashing or a symptom is spreading, a poultry vet or your state extension lab is the right call — fast.
📄 Free printable: The Chicken Never List
The 15 foods that can hurt your flock, on one page — print it, tape it inside the feed-bin lid.
Harold knows your flock's history
Homestead Paradise keeps your flock's health records, lay records, and feed history — so when something looks off, Harold answers with your birds' actual story, not generic internet advice. Snap a photo with Harold's Eyes and log what you find, so next time you'll know what worked.
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