A happy, healthy backyard flock is something all chicken keepers desire. But sometimes injuries and ailments occur, and you need to be prepared to spot the signs.

Sour Crop is something I am very familiar with as we had a hen, Ruth, that was prone to crop issues since she was young (that’s our Ruthie in the picture, just before we started treating her for one of her Sour Crop episodes). You’ll notice her chest looks like a balloon, which is the most noticeable indication that your chicken might have a problem with it’s crop.

What is the Crop?

The crop is essentially a holding tank for food waiting to pass down to the proventriculus, then to  the gizzard where it is ground up for the intestines. First thing in the morning the crop should be flat, basically empty. After a day of foraging and eating, it will be full and firm.

What is Sour Crop?

The crop can form a yeast infection, which in turn results in a thickening of the crop wall and dilation of the crop. The yeast infection is caused by a disruption of the normal bacteria that live in the crop with an overgrowth of Candida (fungus). It is not contagious.

Sour Crop can be caused by a number of things:

• Long, coarse grass- Fibrous grasses that get stuck
• Crop Malfunction or Injury- Crops that are slow to empty can cause a traffic jam to the proventriculus
• Impacted Crop- Food cannot pass through, blockage (another condition, more serious).
• Antibiotics – The usage of antibiotics kills the good flora of the crop, which allows for the bad bacteria to grow.
• Injury – an injury to the crop area can lead to delayed emptying of the crop.
• Diet- Moldy food and foods high in yeast. A chicken should also avoid sugary foods and bread. (My hen would get sour crop every time she had bread)

How Do I Know it’s Sour Crop?

The fermentation of the trapped food and fungal process creates the puffy, gassy crop. It will almost feel a balloon, and the crop will be visibly distended. Sometimes you might hear gurgling if you listen close to their chest, and oftentimes their breath will smell sour, hence the name of the condition. In severe cases, you might see liquid discharge from their beak. A hen will most likely stop laying eggs. 

The chicken will also sometimes display body language that is indicative of their discomfort, such as pecking at their chest or cranking their neck to the side (trying to clear their crop). Weight loss can also occur the further the condition progresses.

What is the Prognosis?

This condition should not be ignored. If Sour Crop is left untreated, the chicken can die. The dilation of the crop and fungus will prohibit food from reaching the proventriculus, eventually leading to undernourishment and starvation.

How Can You Treat Sour Crop?

Sour Crop can be treated a number of ways, some are more effective than others. All treatments have one thing in common; isolation.

When you see your chicken has signs of Sour Crop, the first action should be removing the chicken from the coop and putting it in isolation. I usually have a clean dog crate on standby (the collapsible kind) to set up a makeshift infirmary.

The chicken should have access to clean water only for 24 hours. You want to give the chickens crop a chance to clear. Adding Oregano Oil to the water is helpful.  

Before you crate the chicken, you’ll want to induce vomiting. (I know, it sounds horrible, but it’s a necessary evil.) It’s actually quite simple, but you’ll want to be careful.

1. Hold the hen upside-down with her head facing the ground.
2. Massage the crop upwards to her head to induce vomiting. It will sound and feel like a burp coming from it’s chest.
3. Once you see the chicken vomit, let her clear her mouth and esophagus before massaging again. Repeat until the crop feels less distended and the liquid stops coming out of her mouth. Note: It’s important to keep the chicken upside-down during the entire process until the liquid stops coming out, as you don’t want it to aspirate the vomit.

On day two, you may introduce soft food back to the isolated chickens diet. Try plain yogurt. On day three, I usually give mashed  banana and yogurt. A probiotic powder mashed into banana, applesauce, or scrambled eggs also works well, too. On day four, if the crop feels empty, it is safe to introduce normal food that has been soaked and softened.  Do not introduce hard grains or grasses until the chicken has had zero symptoms for 48 hours.

If all of the above fails, you may be in for a visit to the vet. Our vet often prescribed Nystatin, which is an oral anti-fungal medication. This always worked for us when we orally injected it into the chicken twice daily. However, this means you must refrain from eating the chicken’s eggs for two weeks afterwards, which can be risky if you don’t know who laid what egg. Although, it may take a couple weeks for her to start laying again as her body works to recover, so this might not even be a concern.

Sour Crop Prevention

Once you’ve cleared up the Sour Crop, and you have a happy healthy chicken again, you might be wondering how to prevent future cases. The first step is to add apple cider vinegar to the water weekly (we do 1 TB per gallon). Apple cider vinegar has so many health benefits, and it’s also a natural anti-fungal.  (Make sure you buy organic with the “mother”). Adding a probiotic powder to their feed is also helpful, but can get expensive.

Make sure the chickens do not have access to twine or string from hay/straw bales, and always refrain from feeding them yeasty breads or sugary foods. It also might be a good plan to check the yard for any tough, fibrous grasses.