Chris ] writes
Is it OK to bury cat droppings?

Well, (some) cats do ;-)
The theory is that the closer the digestive system is to ours, the more
likely it is that the faeces will carry organisms that are a problem to
us. So herbivore faeces are no problem, and we happily use horse manure
on the garden. Human faeces are potentially a problem (though still
used, I believe, in some parts of the world). Dogs and cats are
carnivores, and probably not a good idea to use their faeces in bulk.

Also, if it's come from a litter tray, the litter is basically clay and
not particularly useful to your soil.

--
Kay