The New Budgerigar Disease (In England)
The Latest Report
© By John Baker. (England)
© By John Baker. (England)
Since the last insert in "The Budgerigar" there have been some developments with regard to this condition. It was thought that the disease first appeared in November of last year (2002), but it now seems very probable that there were a number of cases earlier than this and the first one that I saw dates back to Spring, although at the time, it was not recognised. There have also been reports of some fanciers losing large numbers of birds during last Summer and early Autumn. The most recent case I saw was in early January 2003.
The disease spreads relatively slowly through a stud, with deaths occurring over several weeks. While a few birds do recover and others never go down with the disease, it seems that on average about 80 to 90% of birds in an affected stud will die, as there is no effective treatment for the condition. All the cases (with one possible exception) seen since last November, can be traced back, either directly or indirectly, to a source in the South-East.
The cause of the disease is not definitely known but it seems probable that it is caused by a germ called Adenovirus. Tests to confirm this or to find other viruses that might be involved are continuing, but do take a long time, results are expected in the next 2 to 4 weeks. There are many strains of adenovirus, some of which are mild in their effects, and some that are very virulent, if this is confirmed as Adenovirus, it will be one of the nasty ones. This disease certainly has nothing to do with the outbreak of BIRD FLU occurring on the continent at the moment.
As this disease seems rather to have died down at the moment and may have disappeared, the fancy as a whole, does not need to take any action and there is no need to cancel shows. As far as the individual fancier is concerned, the buying of birds is fine, as long as sensible precautions, as detail in an earlier, publication are followed. Certainly, if a fancier, has a number of birds dying for no apparent reason, then NO birds should sold or shown until the condition is diagnosed and treated, or it disappears.
Adenovirus causes disease in all types of birds, although some types of Adenovirus only affects certain types of birds. In Budgerigars, it is reported as causing :- depression, loss of appetite, diarrhoera, and bleeding from the back passage. With some types there are also signs of the nervous system with tremors and convulsions. Not all of these symptoms will be seen in every case, in budgerigars, death following a period of enteritis is the usual presentation. In some cases, the bird dies acutely, and may found dead on the floor of the flight. Internally the disease can affect the intestines, the liver, the spleen, the pancreas and the kidneys and on occasions, the brain. Sometimes there is also some conjunctivitis. The main route of transmission is via the droppings but it can also be transmitted to the chicks through the eggs, but it is NOT known if this happens in budgerigars. Although some preliminary evidence that the virus causing the "NEW" disease, does not transfer from generation to generation via the eggs. If this proves to be Adenovirus, then not only the birds which have recovered from the disease, but also those who have not shown any symptoms, may well carry the infection, for how long, is not known.. Once outside the bird the virus is very resistant and unless it is killed by disinfectants, will survive for long periods.
One of the features of this infection is that it causes depression of the immune system and thus the birds are prone to any other infection which happen to be about. In the present outbreak both Psittacosis and Escherichia coli infections have been seen and in some cases, have been responsible for the death of the birds before the virus could kill them. As this disease seems to have largely disappeared, I don't think it should be of major concern to the fancy as a whole, although the relatively few studs that have been affected, have suffered serious losses. Obviously veterinary colleagues and I am keeping a close eye on the situation and you will be informed should it reappear.
Published : 18/5/2003
Editors Note: The views expressed in this article are provided for your information and your personal assessment. They are not necessarily the views of the BSNSW or endorsed by the BSNSW.