Noisy breathing

Hello - my 12 year old border collie has had noisy breathing and a changed bark for over a year. But it's noisy on the exhale rather than the inhale. The vet did a scope to check for LP and said there were no problems there. Plus heart was OK and no evidence of tumours. But an X ray revealed lung inflammation and they said she had chronic bronchitis. Which was a surprise to me because she didn't have the trademark cough. She started on the dread prednisolone but I'm trying to get her off oral steroids - even lowish doses have immediate side effects. For the part 3 weeks I have been giving her inhaled Flixotide (fluticasone propionate) via an Aerodawg - which is reckoned to be a safer method of administering steroids - plus 2 mg oral prednisolone on alternate days.
The vet also prescribed Vivitonin - on account of the bronchodilator effects - but that hasn't seemed to help.
The vet agreed there could be an allergic component but was reluctant to prescribe something as she said there were so many different kinds and I could end up trying different ones for ages. She suggested Piriton (chlorphenamine maleate). That worked wonders - for all of 4 days Then I tried the generic form of the US version of Benadryl (diphenhydramine) with no effect at all. I should add I don't use chermicals in the home and keep it as dust free as possible.
I'm just wondering whether there is anything else going on in addition to the bronchitis. She has not been tested for heartworm/lungworm. Could it be that? Also they never tested for infection so antibiotics were never considered. But I'm reluctant to put her under more anaesthesia for tests. Or maybe I should be asking the vet for a different, prescribed antihistamine?
She did have the occasional single cough or wheeze - say once a day - but that has mostly stopped.
Just to add she is otherwise fit and well and romps around the house no problems. It's just that on a walk she starts with the raspy exhale and increasing panting - sometimes after a couple of hundred yards and sometimes much sooner. It's worse in the heat so she is under house arrest at the mo.
I'm going back to the vets next week and would welcome any ideas. Cheers

This has been going on far too long, as for a referral to Calder Vets in Dewsbury, they are not that far from you. I have nearly lost several of my dog in the past, with most vets I would have but Calder gave them a really good quality of life for several years.

I used to have a Staffie, she was a foster girl I kept, I nearly lost her when she went in to have lumps removed, thankfully they have Consultants there and were able to save her life. This is Ellie's story http://tracheotomy-in-dogs.yolasite.com/ We had to have all lumps taken off because most were malignant, even after the tracheotomy she had quite a few taken off successfully.

Thanks I don't want to turn this into a rant about the current vet but the same practice advised a friend to put down a blind five year old collie that she had rescued 'because it would never settle'. That dog has turned into the most amazing happy and healthy companion. You would hardly know he was blind.
I've even been looking at holistic vets which offer acupuncture etc. At my practice they look at you as if you dropped off the moon if you even ask about making your own dog food .

My advice is always the same in these cases. If you are not happy and satisfied with what your present vet tells you or the treatment they are giving your dog.

Go and see another vet. Get a second opinion.

When my Greyhound had an operation on his spine Calder used arnica cream because his back legs bruised as well as frozen peas to bring down the swelling, Joachim the vet who did the operation and is one of the consultants was very upset because Merlin had bruised it had never happened before. I asked him was this the first Greyhound he had done this operation on as their was no fat on him.

The have branches at Brigghouse Huddersfield, Mirfield and Heckmondwick if you want to change vets but this needs the consultants at the hospital in Dewsbury. The web site is www.caldervets.co.uk.

Vets are not trainers or behaviourists, they do very little about this when training, they are vets, I trust all my dogs with them when they are ill or injured but for training and behaviour I ignore what they say.