Sour Crop in Chickens

Chickens are pretty resilient creatures but sometimes they get sick. Many times, by the time you see the signs they’ve actually been sick for a while. One thing that can be fairly common is a condition called Sour Crop…and yes, it’s kind of as gross as it sounds.

What is a Crop?

Before finding out what Sour Crop is you first need to know what the crop is and what it does. Alright now prepare yourself because I’m about to get all science-y on you.

The crop is a pouch-like organ that is very important to the digestive process and it is found at the end of the esophagus in the upper part of the chest.

If you ever see a chicken with a big baseball shaped protrusion in their chest that’s a full chicken! That means she was gorging on plenty of yummy treats. That’s a happy chicken! Yay! The girl below definitely has had a good day!

brown chicken

Once a chicken eats it goes first into the crop to wait for the digestion process to begin. Think of the crop as a waiting room in a doctor’s office. When the nurse calls you back you will go through a hallway. For a chicken this “hallway” is the proventriculus which is a rod-shaped organ located between the crop and the gizzard.

The proventriculus or glandular stomach is where digestive enzymes are released to begin the digestion process. Hydrochloric acid and enzymes then break down the food further than the initial salivary enzymes.

Then what? Well, after the nurse finishes walking you down the hall you are led to the exam room. This poultry “exam room” is called the gizzard. Once the partially broken-down food reaches the gizzard it is ready to be fully digested.

The gizzard is where the chicken, or any bird, grinds down the food into a paste with the help of grit. Grit are tiny rocks and it’s something that chickens naturally eat as they free range. If your chickens do not free range (and sometimes even if they do depending on the environment) you will need to supplement with grit.



Grit helps aid in the grinding of food in the gizzard. Since chickens don’t have teeth you can picture this grit as the tiny teeth that grind up their food. It’s essential for their health so their bodies can function the way they are meant to.

So, when does all this happen you may be wondering? This whole process from crop to gizzard typically takes place at night while the chicken is roosting. When they wake up in the morning they should have empty crops and need to go out and refill them throughout the day.

What is Sour Crop?

Are you overwhelmed by all the science yet? I sure hope not since I’m not nearly done. Lol.

Now that you understand a bit better how the chicken digests its food you can get a better grasp on diagnosing and treating sour crop.

So, what is sour crop?

Sour crop is actually a yeast infection in the crop. Yes, a yeast infection! A buildup of bad bacteria and not enough good bacteria cause the crop to stop functioning properly. Since a chicken doesn’t have a gag reflex the crop will just fill up and can eventually cause death.

Sadly, we have recently lost a chicken to sour crop. We diagnosed it too late and by the time we started treatment it had gone untreated too long and she passed away. RIP Ladybug! You were such a sweet girl!

This buildup of bad bacteria is yet another reason why we’re in the process of coming up with our own feed recipe. Many of the commercial feed companies add yeast to their food. Why, you ask? There’s a tax break that these large companies get for adding it to their products. All this added yeast, however, ends up causing issues in the flock.

Terrible, isn’t it?

How to Identify Sour Crop?

Does your chicken have sour crop? How can you tell? The easiest way to check would be to wait until morning before they’ve been able to eat anything. Nighttime is when the chicken innards are hard at work! The crop empties and the gizzard digests the food so when you check a chicken’s crop in the morning it should be flat and empty.

Because most of us don’t usually check every chicken crop on a daily basis, sometimes you can end up missing that particular sign for a while which will then lead to other more noticeable symptoms.

“Ewww what stinks?” Well that could be your chicken’s breath. Yuck!

There’s a reason they call it sour crop. It has a sour smell to it because all the food has been sitting, fermenting and not moving toward the gizzard.

Thankfully when Ladybug got sour crop, I was sick and my nose was stuffed up. Couldn’t smell a thing. The rest of my family did though. Ha ha! Most of the time I hate being sick, but this was not one of those times. Lol.

Some other things you’d want to watch out for would be lethargy, diarrhea, drowsiness or loss of appetite. Once you notice any of these things you should definitely isolate your chicken so you can keep an eye on them better.

How to Treat Sour Crop

Giving your chicken probiotics will help to break down the yeast infection that is causing sour crop. For us, we chose to empty the crop by massaging and holding her at a downward angle to force regurgitation. You MUST be very careful because there is a risk of the chicken aspirating if you don’t hold them downward.

Yes, it’s gross. Believe me I know, but I felt I needed to empty her crop so the probiotics could start breaking down the little bit that still remained in her crop. You can give Greek yogurt since it’s loaded with probiotics. I did that and also took a small syringe and put crushed probiotics mixed with water and gave it to her orally. She hated it. Lol.

Prevention is Key!

Knowing how to treat is great but your best bet is prevention. Make sure your flock always has access to clean fresh water. Providing access to grit, which helps to grind and break down their food, will allow their digestive process to continue to work properly.

Sprinkling their water with probiotics will help to keep their crop from developing a yeast infection. Apple Cider Vinegar is also a great preventative measure to take. Use ¼ cup for every gallon of water on a weekly basis and it will prove to be very beneficial for your flock.

Hopefully, you never have a chicken with sour crop but if you do these tips will help your chicken feeling their normal self in no time!

Happy Homesteading & Stay Cuckoo!