No Aspen bedding does not cause respiratory illness. It my have been a viral infection and because the ratties stayed together it spread to all of them. If any of the remaining ratties display illness, immediately seperate them from the others.
Here is some info on this:
QUARINTINE - QUARINTINE!
Treat your new rat like it has the rattie plague! If you have other rats or mice, you must quarintine your rat. Most viral respiratory illnesses are airborne. That means your rat can give or get an invisible illness that floats about on the air. Put your rat's home in a place far away from your other rats. The most preferable place to quarintine is in a separate building. Quarintine you rats for two weeks, at least. If they have been exposed to a virus, they will develop symptoms of it, in this time. Symptoms include, diharrea, sneezing, discharge that is red from eyes and nose, sleepiness, refustal to eat or drink, lethargy, depression or a swollen face. If your rat becomes ill, treat your baby rat appropriately. The internet search engines are full of home remedies for rats. But, in any case, unless you really know what you are doing, do not self-medicate, take your rat to a veterinary for treatment. After your rat has recovered, then start the two weeks quarintine over.
A bit about Viruses...
Unfortunately, rats are not inocculated for common rat viruses. There are many rat viruses that your rat can contract that would cause it to have a cold. Some viruses cause symptoms from a few sneezes to violent respiratory illnesses such as caused by Sendai virus or SDA virus. These viruses can potentially kill your baby rats in a matter of days.
Your rat could have been exposed to a virus at a pet store or at the breeders. How could that happen, you ask? Your rat came from an in-home breeder that only breeds her own quarintined rats. Rat viruses could come into a closed in-home rattery on a breeze through the window. They could have come into the rattery on a bag of food or toys bought at the local pet store that had rats. If the breeder allowed you into their home, they could have allowed others who may have had a virus on their clothes or hands.
Example of virus transmission (the example can be replaced by lice or mites):
When I owned my pet store in 2002, I had many people come in looking for a new pet to replace the one they had that just died of respiratory illness. They thought that because my rats were pedigreed, they were immune to illness. Many people told me stories of how they had to take their beloved rat to the veterinary for treatment of respiratory infection, only to have it die anyway.
They want a healthier rat and begin to "look" at my rats. They hovered over the rat cage and they looked closely at the rats. If my rats are in an aquarium, they have a screen top. If in a cage, they are behind bars. Some people, in their excitement to get a new pet, opened the cages in my pet store and handled the rats.
Now, some viruses can live on a person or object for days. It can take 2-7 days for symptoms of a virus to show after the rat has been infected by the disease. What has these good intentioned people just done to the potentially disease free rats? They have just given them the same virus that killed their rat.
If you have a sick rat or have had one in the past, sterilize your habitats, wash your clothes and shower. Do not go immediately to the pet store or breeder to get a replacement. This is one reason why rats from pet stores or from a breeder can be sick a few days after you bring it home. Always ask permission to handle an animal. Assume you cannot. Wash your hands before and after handling a rat. When you buy a new rat...take it home and quarintine it to protect the rats you already have. Protect your rats from a potential virus that you could bring home and protect the pet store or breeders rats from virus they may have.
Some rats that have already survived a virus or have been innoculated temporarly by antibodies in their mother's milk, will not show illness. But these rats can potentially carry and give other rats a viral illness. This is another reason to quarintine.
If you think your rat has SDAv or a virus...click here for my article about what to do.
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