Even if you offer your pet birds optimal care and nutrition, it can happen, that your Linnies get ill. In case of doubt a bird-expert vet should check, whether that is a bacterial infection, parasites or any other disease. Anyhow it's good, if you as a bird owner learn to deal with possible diseases, their symptoms and therapies to act fast and correct in case of an emergency.
If a bird shows symptoms of an illness like diarrhoea, apathy or loss of appetite, it can be helpful to have a "sick cage" to separate the concerned bird from his fellows. By this, if you did it early enough, an infection of other animals could be prevented. Also the treatment of the bird is much easier.
That cage should be set up spartanic, because it's important, that the cage should be easy to clean to avoid a re-infection. It also should be possible easily to catch the bird out of that cage, to do some medication or other treatment. In that case too many branches or toys just disturb or even may be a source of injury.
Of course it's a different situation, if the bird has to stay in that cage for longer, like Nele had to in the end (see photo above). She wasn't able to fly anyway, so I put in a lot of branches to give her the chance to climb around.
So, please check appropriate literature concerning bird diseases and therapy. For the case of emergency you should have the telephone number of your vet on your fingertips.
Last update on May 11th, 2014