This is a common symptom in young birds and is seen less frequently in old birds. It can be accompanied by some of the birds vomiting; loss of appetite; and can result in a rapid decline and death in 24-72 hours.

This "sour crop" is not a disease but a symptom of a disease process which causes a severe inflammation/infection of the gastro-intestinal system.

The inflamed gut becomes static; it quits moving material downstream toward the vent. This stasis results in fluid just sitting in the crop. Often there is even reverse flow, with bilious material being refluxed into the crop. If the material is expressed or withdrawn, it is usually greenish and foul smelling.

What causes this infection? Often it is a symptom of adenovirus infection. Here the symptoms are produced by the bacteria (usually E.coli) present in the gut.

The adenovirus "opens the door" for the bacteria to invade. It also can happen (the bacterial invasion) without adenovirus predisposing. Other things can predispose or the infection can occasionally be primary (causing infection all by itself).

It can be difficult to treat because antibiotics given orally just sit in the crop, not getting assimilated into the system; therefore no therapeutic blood level of antibiotic develops, allowing the disease to progress.

Injectable antibiotics, along with removal of the stagnant crop contents can save the affected pigeon, but most will not respond once the disease gets to this stage.

Flock treating with a good broad spectrum antibiotic will usually arrest the progression of the disease. Recommended antibiotics include Saraflox, Baytril, Amoxicillin, Cephalexin, and Trimethoprim/sulfa. Treat for 7-10 days.

Dr. David E. Marx D.V.M.