You can take enough to bide you over as your dog obviously has a digestive issue that I'm sure your vet knows about but you forgot to get a letter:-

Pet food required for health-related reasons
No more than 2 kg
are intended for the pet accompanying the passenger
are shelf-stable (do not require refrigeration)
are packaged proprietary brand products for direct sale to the final consumer
that the packaging is unbroken unless in current use]]

Colin

It seems such a stupid rule that you can pay to get your animal across the channel but you can't take a small amount of food. I think it was Julie Grafo that told us veggie food for cats is a no no anyway.

We took a couple of tins of cat food with us although she normally eats sachet food at home and there was not a mention at the UK Port that connected dog/cat with food although the notice on the window pointed out that we had an animal on board. Upon arrival in France there was not a mention of anything except a passport check at the exit.

Randa