I get fresh pumpkin; steam or boil it, mash it up when soft; and freeze it in ice cube trays. Then I store it in a freezer bag and let a cube a day defrost for my kitties. I can't find canned pumpkin here in Australia, but I like making the fresh version as I know there are no additives and the fibre is there to help with Girlie's constipation issues.
@Bron and Sheba and others taught me this. I'm sure everyone knows this, so apologies if I'm stating the obvious...