I will warn you that the surgery should not be your first course of action. Also, you massage the crop rather than trying to squeeze it out. The olive oil works to soften and lubricate the mass and massage will help break it up. Also, provide grit so that as it starts to break up, the chicken can take in grit to further break up the mass. Adding apple cider vinegar (ACV) to the chickens' drinking water will help by reducing any mucous that may be contributing to the problem. Repeat the olive oil and massage several times throughout the day.
One treatment for sour crop is to make the chicken regurgitate, but this can be dangerous because the chicken can aspirate (breathe in) the vomit.
Here is more comprehensive information from the first link in my signature:
Impacted and Sour Crop
Chickens need grit to digest food in the crop. When food gets blocked in the crop and cannot be digested, the result is an impacted crop. It presents as a hard lump in the chest. Check for this in the morning as it can be confused for a full crop, which is normal. The crop will naturally empty overnight if it is simply a full crop, but an impacted crop will not. Sometimes and impaction will rot in the crop and become squishy and foul smelling. This is a sour crop. Both impacted crop and sour crop keep the bird from digesting food properly.
Impacted Crop
Olive oil and massage - olive oil can help loosen an impaction. Simply put a two or three drops of olive oil at the back of the chicken's throat so that she swallows it and gently massage the crop. This may need to be repeated. Make grit available to the chicken, as well.
Sour Crop
Powdered copper sulfate - has anti-fungal properties. Dosage is 1/4 teaspoon per gallon of water, changed daily for several days. This will also inhibit the growth of certain types of bacteria, an added benefit. Can be used with apple cider vinegar.
Apple cider vinegar (ACV) - aids in the removal of mucus build up in the digestive tract that may contribute to sour crop. Can be used with the powdered copper sulfate.
** Recipe for sour crop (
found offsite) **
Coper Sulfate measurements.. be exact
Use 1 gm (0.035 oz) of Copper Sulfate (bluestone) to 2 litres (3.52 pints) of water be very careful about the measurements of the Copper Sulfate too much will kill your bird
Add 2 teaspoons of Apple Cider Vinegar
Mix in some Cranberry Juice to make it more palatable for the birds to drink and disguise the taste of the copper sulfate and vinegar
Give this medicated water as the sole source of drinking water for 4 to 7 days, in some cases you may need to extend this time until you feel that the condition is over
Do not use metal containers only plastic ones
Put the mixture out fresh each day
Suction - in severe cases of sour crop, connect a soft catheder tube to a needless syringe. The catheter must be inserted down the throat and into the crop. This is uncomfortable for the chicken and you may give her a drop or two of Bach's Rescue Remedy to help calm her for this process. Once the catheter is in the crop, carefully pull the plunger of the syringe to suck liquid from the crop.
