Thank you for your patience. There are a few things that could be going on here, but what you have described could certainly be 'laryngeal paralysis' as your friend has described. This is more common in medium to large breed dogs, and the lack of the larynx to open and close properly, does in many ways cause these types of symptoms. Other possible causes we need to consider include a collapsing trachea (windpipe - more common in small and mini breeds), a primary mass in the airway, or an elongated soft palate. Given he has been fine otherwise up until now, the most likely possibility here is the laryngeal paralysis. There is an excellent article that gives more detail on this online here: http://www.veterinarypartner.com/Content.plx?A=2331 so do have a read. The best next step here is further diagnostics to try and get a clear idea of what is going on here and whether your boy could indeed have laryngeal paralysis. This will involve a mild sedation and viewing the larynx, as well as potentially bronchoscopy of the lower airways, collecting respiratory tract samples for analysis (to rule out other underlying issues), and a couple of chest xrays to check the heart size and lungs.
If laryngeal paralysis is diagnosed, then it could well be that your boy will need a surgery to fix this issue. This is done by a 'tie-back' procedure where the floppy laryngeal folds are tied back to open up the airway. This is best left to a veterinary surgical specialist and I would recommend referral if a laryngeal paralysis is confirmed.
All the best with your boy and please do follow up on the above diagnostics with your local vet this week if you can. I hope all of the above makes sense? If you have more questions or if I can help in any other way, please do not hesitate to ask! If you would like to accept my answer, please press RATE OUR CONVERSATION (I am not compensated in any other way). Bonuses are always welcome. Thanks! I hope to work with you again soon!
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