
It's like our own passport need a new one if the old one becomes full. At least it doesn't expire!
There are 12 spaces to record Rabies vaccination, so that should last a dog at least 12 years and possibly 36 if 3 year vaccines accepted where your travelling to.
There are only 15 spaces to record tick treatment, so that would shorten the life of the passport considerably for those using it to enter the UK!!!
There are also 15 spaces for tapeworm treatment. Also 15 spaces for other vaccinations (some countries require).
Only 5 spaces for health certification, but most airlines etc accept them on vet headed paper.