Chirping noises

Question
Hi sandra, quick background story. I bought 2 pet shop rats, day one one had a sevre resp infection (im guessing also pneumonia as his nose was very wet and you could hear gargling in his chest) and was lucky to pull through, his brother also had a resp infection. When they were 6 months old i rescued 2 new boys who were 4/5 months old, They spend about 2/3 weeks in quarrantine as the previous owners rats were really healthy. theyve been in the same cage together for about a month now, One of the 2 new ones bullies every one (chasing them sideways with one leg up, hogging food and hammocks) and they are absolutely terrified of him (hes also hard to handle now and started biting, breaks the skin but not deep, hes not scared of me, he chased me trying to bite me while hissing and poofing his fur!), but hes outgrown the spare cage i had so i cant seperate the group. Since my first myco experience ive taken my rats away with me every weekend so i know their proper needs are met, but last weekend i decided not to. When i was away the cage wasnt cleaned, and i also vaccumed before i left (the vaccum lets off quite a bit of dust) but i did keep them out of the room for it. They were also treated for mites a few weeks ago (but it was probably too much protein as ive seen an improvement since cutting it down)
sorry for the long message, almost over! I was away friday-sunday, when i came back my gorgeous little boy was chirping (first pet shop rat that didnt have sevre infection), only when trying to put him away (note hes scared of one cage mate) or if hes really playful, but it sounds different to my last myco experience, he also does a big sneeze after a few chirps, i also heard ONE other rat chirp for a few seconds, and they all seem sniffly. although no one seems prophy apart from tiny amounts when they wake up.
Is it normal for it to come on this quickly?
ive made an appointment with the same vet, although shes not experienced she is open to suggestions and helped me a lot last time. What do you think caused it? reading back i sound like such a bad owner but things have been hectic lately!

p.s im from the UK

Laura

Answer
Hi Laura

I can see the aggressive rat now ...running around poofing up, running sideways and spitting and hissing. The little stinker!! I would get him in another cage as soon as you can. I dont like that he bites the others and have had rat owners lose rats after serious bites.
I am sure your already working on getting another cage for him but just thought I would still mention it.  The stress he is causing the other rats can actually lead to illness. Stress hinders the immune system and can cause the rats to be more prone to myco flare ups since they naturally harbor the bacteria anyhow, it only takes one wrong thing to occur and it can trigger the body to respond this way. Also, there is a certain way to really treat myco, and that is to use the right medication for a full 30 days. When they have a relapse, they should be put on the medication for the rest of their life or they end up with lung scarring that eventually leads to death.  My site, sandyscrittercity.com has more info about mycoplasmosis and how to prevent it the best you can and how to treat it as well. Did your vet give your rat baytril?