Ornithosis, also called Psittacosis is caused by an infection by Chlamydia Psittaci.
Much has been written about this but it is my opinion its role in many having poor breeding results is underestimated. If one looks at the symptoms, infertility, dead in shell, failure to lay eggs, sudden death of breeding hens, young birds dying all of a sudden being only a few weeks old, balance problems, we would be tempted to think this is where we are in Border breeding. Other kind of infections also could show similar symptoms, but this would be occasional, and not with this kind of broad spectrum symptoms.
The problem with this disease is we almost don’t notice it outside the breeding season, the birds look all right, hens looking good, cocks singing loud, nothing seems wrong…. until the breeding season starts. At this time, demanding for our birds, problems pop up, eggshell problems, not laying hens, dying hens, some lethargic hens, and an occasional cock not getting the right breeding condition. There might also be a link with the calcium metabolism problem we have, as this infection can impair liver and kidney function, necessary for vitamin D activation. Even those who consult a vet pre breeding with examination and standard cultures of stool samples do not reveal any problem as it can’t be demonstrated in regular stool cultures. If wanted one can ask the vet to look for it, but for this swabs have to be taken from the conjunctiva, choana and stools. Special tests can be done to demonstrate if our birds are infected. These tests are expensive and the results take some time. But I think in our breed worth thinking about!
It is my opinion this disease is underestimated by us because of the absence of symptoms out of the breeding season, as in most cases this is a “low grade” infection.
I think this is one of the diseases which do not often give problems in strong breeds of birds, but in the more fragile breeds like the border, I think we have inbred some kind of lower level of natural immunity, which makes the birds more vulnerable to these kind of infections. I have knowledge of one fancier breeding borders and using fifes for fostering and having an outbreak of ornithosis in his borders, but with not one noticeable problem in his fifes, to me a matter of natural resistance and immunity. Building up natural immunity from winter on is also very important, an art known by experienced fanciers who know nothing is free!
Much has been written about some pre breeding antibiotic cures in order to get some better breeding results. Most do think about coccidiosis and give some sulpha or Baycox treatment over winter, but when speaking of other pre breeding cures there seems to be some mystery, as we all seem to avoid this being spoken of.
I know some fanciers do an over winter cure with doxycycline, a 30 day treatment , something in us telling this seems a long way, with the possibility getting the some candida infection during this period of time, and being afraid getting the birds out of condition. The duration of this therapy, in contrast with humans, in which we only treat for 7 days, is because of an increased level of re infection in bird sheds, transmission by moving dust, re infection from the environment almost absent in humans.
Enrofloxacin (Baytril) is also effective as to clean up the birds but the normal dosage of Baytril 10%, 2 ml per liter of drinking water seems not enough and higher dose regimens have to be used. Research in now being done as to look for the right dose to get the job done. I will keep you updated on this as right now some European fanciers are trying different dose regimens pre breeding. Care has to be taken not to get toxic levels which could give rise to renal dysfunction and balance problems. Positive results have shown Baytril 10% medicated food but at a dose of 1000 mg/kg of food, also for 21 days.
Tiamulin ( Chevimulin T) has been used by others as to combat Mycoplasm organisms which, as stated by some, often seem to go hand in hand with the circovirus infections as for now, the possible cause of the “black spot” syndrome. But when it comes to ornithosis tiamulin does not seem to be able to eliminate the Chlamydia organisms from the bird body, as intracellular concentrations seem to be too low for eradication.
Another setting, as often met, is meeting the problem during the breeding season, and this is where things get tricky, if one knows he has a problem, but the use of docycyline and enrofloxacin is a contra indication of being used, as doxycycline could bring us soft shelled eggs and bone development problems and enrofloxacin could interfere with cartilage formation in the incubating chick. Consulting a specialized vet is recommended as if nothing is done, the breeding season is over.
A new treatment at this time of breeding could be the use of azithromycin, a drug also effective in eliminating Chlamydia and Mycoplasm infections with success. It is being used in human medicine for these indications and can be used by babies and if needed, by pregnant women. Some studies have being done in birds, and the first results seem very promising. I will keep you updated, but if so, this could be a promising drug for the future, as well in the pre breeding period, only to be given for 3 days, as well when needed in the breeding season as no negative effects as to fertility, eggshell strength or bone formation is known. This drug accumulates in the white blood cells of the body, so they are integrated in the first line defence of the body, and after being given for 3 days, still do the job for about another 12 days.
It is not my advice to promote the use of drugs in our birds, but as breeding problems are common in our sheds, I hope this could trigger some discussion, and as often said, breeding reports, as well in the positive and negative way can teach us which way we have to go in this.
Maybe the most important lesson is to spend some more on pre breeding vet examinations, especially in concern with this particular infection.
Dr. Jan Vanderborght MD