I think it is best to have kittens vaccinated for the first 2 years.
This enables them to build up a good immune system.
When i was young and my parents always had cats we never vaccinated them because it was not available.
However now it is.
I only vaccinate for the first couple of years because having had a cat that after 6 years of being vaccinated had a bad reaction to it.
It has now left her with cold symptoms and runny eyes and nose.
I have since heard from a breeder that the first 2 years are the most important.
The other thing you have to weigh up is are they going to be out door cats?
If so are there many cats around you?
I hope this helps.

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