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.
Ivermectin is basically acts like a transporter of zinc, zinc is the real guy who is helping.
Vitamin D is also useful with full of long term data and RCTs on covid. We kinda know the mechanism already. Media doesn't even mention vitamin D for a reason.