Rather than getting all these vaccines repeatedly for bacterial or viral respiratory illnesses, perhaps a course of oral doses of ivermectin could be used.
Was the coronvirus/adenovirus treatment oral ivermectin for 5 days? That would probably work for all animals. Just need to figure out the dosage.
Subcutaneous if really necessary. But oral is obviously safer and easier.
a farm supply store should carry the ivermectin horse paste. it's about 9 bucks a tube where i'm at. not sure how many loonies that converts to :)