The advice hub Sour Crop

Sour crop is a yeast infection in the crop leading to thickening of the crop wall, dilation of the crop and birds losing condition and possibly dying. Sour Crop is caused by a disruption of the normal bacteria that inhabit the crop with an overgrowth of Candidia (a fungal species) often occurring.

The crop is a part of the oesophagus (food pipe) where the initial stages of digestion occur. You will find it at the base of your chicken’s neck and you can sometimes feel the contents whether it is food, grit or water. We are frequently contacted when owners have birds which appear off colour and have an enlarged crop. These chickens have often stopped eating and are dull with bad breath and they will also have large fluid filled crops.

There are two common conditions of the crop: crop impaction and sour crop.

The route cause is often difficult to determine but you should check the condition of your feed store and always ensure your chickens have fresh feed. Feeding foods unsuitable for chickens and mouldy food are thought to be potential causes of Sour Crop.

Treatment is also difficult as there is no specific treatment for sour crop. The use of copper sulphate has been successful but this must be carried out under veterinary supervision. Manually emptying the crop is difficult and the underlying fungal/yeast infection needs to be controlled. The crop can also become impacted, in which case removing feed and manually massaging the crop can be of use.

In many cases a dilated crop is difficult to treat and the prognosis is not good. This treatment involves draining the crop. One method, which we do not recommend, is to turn the bird upside down and let the fluid be regurgitated however there is a real risk of choking with this treatment. Chicken Vet recommends the use of local anaesthetic and to drain and wash the crop with sterile saline. (This is a veterinary procedure).

Although the exact cause for this condition has not yet been fully determined antibiotics may be prescribed in some cases. The problem with this is the antibiotics will kill off the friendly crop bacteria making an initial improvement but then the condition may reoccur. Using Beryl’s Friendly Bacteria has been found to restore the normal crop bacteria. This will coat the lining of the crop making it a more hostile environment for fungi to grow. You can use Beryl’s Friendly Bacteria 48 hours after the end of the antibiotic course.

Furthermore, your vet may prescribe an antifungal product for use after surgery.

This condition commonly recurs if there is an underlying cause that can be difficult to determine.