Candida (Yeast Infection)

Causes

Candida albicans is a yeast infection. It frequently occurs as a problem secondary to another disease, but also can develop on its own as well - perhaps from eating foods that have been left out too long or from stress or anything else that might create a weakened state in the bird's body.

Antibiotic treatment also can lead to yeast infections. The theory behind this phenomenon goes something like this: Antibiotics wipe out the gut flora, good and bad. However, antibiotics are useless against yeast. Thus, the naturally occurring Candida organisms in the gut suddenly find themselves in a position where they have no competition for resources. Even if you believe Dr Rob Marshall's sterile bowel theory that ascertains that gut flora and yeasts are not found in healthy finches, you still have to consider that when treating with antibiotics, you are not dealing with a healthy bird. Since yeast is an opportunistic infection, it is especially likely to be present and present in higher numbers when a bird is ill from another problem. Once the yeast finds itself without competition, it begins to multiply rapidly, quickly reaching numbers high enough to cause illness in its own right.

Symptoms

In my experience, Candida is a slow developing problem. It usually is not a sudden killer where the bird is perfectly healthy one day and then dead the next. Instead, fluffed bird syndrome develops slowly, where the bird becomes less and less active, sleeps more and more, fluffs up, and loses interest in its environment. In my experience, it can creep up on you: the initial symptoms are subtle and you dismiss them, then you get used to the bird appearing this way, then the symptoms get subtly worse very slowly over a long period of time. Another characteristic of Candida that I have noticed is that when the bird is awake, it is frequently in the seed dish, appearing to eat a lot. I assume this is because the yeast interferes with proper digestion and absorption of nutrients, so the bird needs to eat more to keep up its energy. This is also characteristic of Avian Gastric Yeast, in my experience.

Prevention

You can take steps to prevent Candida by keeping the environment clean, removing fresh food before it gets old, and administering a probiotic on a regular basis. Probiotics are frequently prescribed during and after antibiotic treatment to prevent yeast infections. Probiotics will generate gut flora, thus creating competition with the yeast for resources and "starving" it out. The flora produced by probiotics also will make the gut more acidic and thus less hospitable for yeasts. Even Dr Marshall acknowledges that probiotics reduce the risk of yeast infections after antibiotic treatment, although he attributes this mainly to the acidifying of the gut. Avoid routine treatment of your flock with antibiotics as not only will this increase drug resistance and affect the natural immunities of your birds, it will also lead to yeast infections.

I administer probiotics (Avi-Culture) in the eggfood 3 times a week as a preventative. In healthy birds that have shed a few branching yeasts in their droppings, I have seen probiotics administered every day for two weeks eliminate the problem without needing medication. Apple cider vinegar - a substance frequently touted to prevent yeast infections because of its acidic nature - did not show me any results, even when increased from the recommended dosage of 5 ml per liter all the way to 2 Tablespoons per 6 ounces. It has been suggested to me by aviculturists who also study nutrition, that the apple cider vinegar is neutralized before it can have any significant effect. However, adding apple cider vinegar will raise the pH of the water it is mixed with and thus keep bacteria in the water supply under control.

After adding the probiotics to my regimen, I went 1.5 years without seeing yeast in my birds. I currently (time of writing: August 2006) do have an owl finch with a yeast infection. This bird also was carrying a protozoa, so the yeast infection may be secondary to other health issues. This bird also has a history of Avian Gastric Yeast infections, suggesting his immune system is not what it should be.

Treatment

If one finds a significant number of yeast organisms in the droppings or if the bird is visibly ill from a yeast infection, probiotics alone are not likely to help (in my experience). Medication is necessary. Nystatin is the most commonly prescribed medication. You can get this from your vet in an oral suspension that likely needs to be administered twice a day.

Because yeast is not a quick killer, if the bird is not showing symptoms, I sometimes decide to treat myself before bringing the bird to a vet. Nystatin is available from pigeon supply stores like Foys and Jedds in a product called Medistatin. Instructions are given for mixing this product with soft food. However, I have found that this does not work well - it cannot provide the necessary dosage in a reliable manner - at least in finches.

Instead, I have chosen to make my own suspension. I started with the formula used to administer Medistatin to handfed chicks via crop dose. At this time, I do not have experience with a crop needle, so I adjusted the formula to create a small but concentrated sample that could be administered orally to the beak via a small (.3 cc) syringe. For a 10-gram bird, this came to mixing 2 grams of powder to 8 ml of water. I keep this mixture refrigerated (I don't know if this is necessary, but it seems the safest approach), shake well before using, and administer .02 cc inside the beak twice daily. I cannot guarantee that it is safe or effective to treat this way - it is an experiment I have tried. If you choose to try it, you do so at your own risk.

Because yeast infections frequently surface alongside other problems, you may need to administer nystatin at the same time as other medications. I have been told that nystatin is fairly safe and can be used with most drugs (although never combine multiple drugs in the same water unless you have confirmed that this is okay). The only drug I have administered at the same time as nystatin is ronidazole (Ronivet-S) for protozoa. I witnessed no adverse reactions to using both medications at the same time.

If nystatin fails to eliminate the problem, there are many other choices. Nystatin is usually the first choice because it is a very safe drug. However, Candida can become resistant to nystatin. Also, with time, Candida infections can become systemic - spreading beyond the digestive system. Since nystatin must come in contact with the yeast to eliminate it, it will not be effective at eliminating a systemic infection. What you will likely see is that the bird looks better when on medication. Under the microscope, the medication will eliminate many but not all of the branching and budding yeast organisms. However, once treatment is stopped, the bird very quickly returns to looking ill and the yeast organisms are again seen in high numbers in the droppings.

Ancoban is another drug that can be prescribed by your vet. I have found this drug to be as effective as nystatin, but to also have trouble if the infection is systemic. I have been told that Diflucan is effective against systemic infections, but have not yet had the opportunity to try it. Your vet will likely have to prescribe this drug for you.