Long time finch breeders will be aware of this problem but newcomers may not. Cochlosoma is one of those diseases that can cause problems within a flock yet is easily controlled.

A cochlosoma infection will lead to debilitated chicks, chicks with shrivelled skin, dehydration  and yellow stained feathers. Moulting problems, being fluffed up and moist bulky droppings are also common with Cochlosoma. Once the problem is recognised the treatment is as easy as Ronivet S in the water!.

Cochlosoma is a protozoa, an organism that lives in the gut of the bird and has the ability to move using 6 little “ tails “ ( flagella ). It does not cause major microscopic damage to the gut wall but certainly upsets gut function and probably reduces the ability of the bird to absorb its food.

Chicks are infected  between 10 days and  12 weeks of life. Often infection is suspected when the fledging rates are very low due to chicks dying in the nest.

Adult birds, although they rarely die from the disease can have bulky, moist, yellowish droppings and also pass whole seed ( whole seed in the droppings is never normal! ). Chronically infected adults may also have feather loss around the face which does not respond to treatment.

The organism can survive outside the bird in moist conditions and is believed to be transmitted by direct faecal contact or direct feeding from adults. Bengalese are considered a carrier species and are often implicated as spreading this disease to fostered chicks of other species.

Diagnosis is difficult, a fresh warm dropping is the best sample to examine under the microscope for the moving protozoa.

The safest drug to use is Ronivet S. 1 gram per litre  of Ronivet for 7 days is highly effective as a treatment for this disease. Finches should be treated 2 - 3 times yearly and all introductions should be quarantined and treated before release into the aviary.

Cochlosoma is becoming more common in Australia so finch breeders should be on the lookout for the telltale signs of an infection and if in doubt begin a treatment programme before deaths escalate.

Ref: Brown, D. Annual Conference Proceedings, AAVAC, Oct. 1998. Canberra.

P 175 - 193.