Lately I’ve been noticing some signs of yeast overgrowth in my flock. I have three silkies with pendulous crops which makes them prone to this common issue because feed and other material takes longer to pass through their crops. In addition to lack of appetite, isolating, and weight loss, poo that is slightly gray in color, dark diarrhea, or droppings with excess milky-white material are signs of too much yeast. It’s also possible for symptoms to appear respiratory in nature, including wheezing and open mouth breathing. According to Poultry DVM, causes range from the following: “factors such as prolonged or inappropriate antibiotic use, corticosteroids, malnutrition, stress, underlying illness, and/or excessive use of disinfectants can predispose chickens to candidiasis.” See more at: http://www.poultrydvm.com/condition/candidiasis
In addition to treatment, it’s a good idea to add probiotics to your flock’s water to help restore balance in their crop:
Yeast overgrowth is present in virtually all cases of sour crop, but it’s important to note that your flock may be struggling with an overgrowth of this bacteria even without sour crop symptoms. There are multiple ways to treat yeast overgrowth, but adding acidified copper sulfate to your flock’s waterer once monthly for 5 days can help prevent an overgrowth from turning into a more serious health issue.