I recently gave away our one year old Persian male cat after keeping it for 10 months. After 8 months of keeping our cat, my wife developed asthmatic symptoms, but since we gave the cat away my wife is fine.
Was it the cat or something else? Or is it possible to have such symptoms after 8 months of keeping cat?
And secondly, is there a possibility she will have same problem if we keep a dog?
Allergies to animals, particularly furry ones, can be across the board rather than species specific. Usually the source of this is dander in the fur and cats, dogs, rabbits, etc. will typically have this and so, yes, it's entirely possible that you'll have the same problem if you get a dog.
Allergy symptoms for someone may take a bit of time to develop and an allergy can come on at any time even if you previously had none. At any rate, getting an allergy test might be a good idea, just to confirm. If she does have animal allergies, there are some options for cats, such as a Devon Rex, that can work. My sister has very bad animal allergies and was able to keep a Devon Rex.
The main cause of the allergies is proteins in the saliva. When the cat grooms themselves these are deposited on the fur, when the fur and dander are flying around you get exposed to these proteins too. Some cats have a mutation where the proteins that people are allergic to are not in their saliva... this results in a cat that doesn't provoke allergies. A shorter hair cat like a Devon Rex, a Sphinx... will have less surface area (less fur, & less cleaning of fur) and thus might not provoke the same intensity allergic response.
Another option is to get shots. The offending proteins are injected into the blood of the human with the allergy. Typically the immune system learns these aren't a problem and the allergy goes away. With asthma, given that it can be severe, I'd discuss that with your doctor first.
