Poppy keeps having bouts of heavy breathing and panting (which are quite distressing to watch) while at rest. Its almost like an asthma attack or fit of some kind. Phil has asthma and often gets attacks and her symptoms are so similar. The vets have checked her heart and lungs but cannot find anything wrong with her :( but she has gone back today. We think she may need antibiotics, she has had kennel cough before....could it be that? or is there any other causes which could be responsible?

Aparantly so, although it isn't common

http://www.animalhospitals-usa.com/dogs/asthma.html

http://www.nativeremedies.co.uk/petalive/amazapet-feline-canine-asthma-treatment.html

http://www.guide-to-asthma.com/content.asp?pagerequested=221580&category=Understanding_Asthma_in_Dogs

Have you read Lotti's thread about reverse sneezing?
Could it be that?

Have you read Lotti's thread about reverse sneezing?
Could it be that?

sooz it could be this:
It seemed at first that Eddy was having some sort of asthma attack or hyperventilating but it turns out it's something many dogs get - there's a link in my thread to explain it and how to help shorten an attack.

yes they sure can have asthma. They can also have hay feaver lol this could also be reverse sneezing as the discription given .
However we did have one dog years ago with same symtoms and that was caused by a tumor and the vets never found this untill it was too late.

Shes on antibiotics (7 day course) so will see how she goes. If there is no improvement then its something we can look into with our vets as he did suggest it to us today.