A crop infection, also referred to as sour or slow crop, is a serious condition in your cockatiel. If it isn't treated quickly, your bird could die. If your cockatiel shows any signs of a crop infection, or you suspect there is a problem, contact your veterinarian immediately. With quick treatment, chances are good that your bird will make a full recovery.
The Crop's Purpose
Your cockatiel's crop is similar to your esophagus, but serves a slightly different purpose. Rather than using the surrounding muscles to move food down the throat, a crop temporarily holds food that your bird has just eaten. In the wild, this lets a cockatiel eat a large amount of available food quickly and then fly to safety, where the food can move into his stomach and through his digestive system at a steady rate, instead of all at once.
Types and Causes of Infection
A crop infection can be bacterial or yeast-based, with treatment based on the specific type. Antibiotics are used for bacterial infections, while yeast infections are treated with antifungal medication. Food that is trapped or stuck in your cockatiel's crop is the usual cause of an infection, but it can also be caused by dehydration, lacerations, burns and an organism called trichomas that dilates the crop. Food should leave the crop within 24 hours. If it doesn't, infection-causing bacteria or yeast begin to multiply.
Regurgitation or Vomiting
Regurgitation, or vomiting, is usually the first sign of a crop infection. Since cockatiels are very good at hiding illness, it may not be obvious that your bird is throwing up food if you don't catch him in the act. Look for thick mucus or moist pieces of food stuck to his beak, moisture on his head or throat, and strange snakelike neck movements. Since vomiting is so closely associated with crop infections, you should contact your veterinarian right away if your bird regurgitates or vomits.
The term "sour crop" to describe a crop infection comes from the musty or sour odor associated with the condition. This odor is caused by the combination of old food and bacteria or yeast. The gases created by the rotting food emanate from your bird's mouth, making the condition instantly recognizable as soon as you smell them. If your cockatiel's breath smells foul, the most likely cause is a crop infection.