Dogs don't eat for days because sponges are absorbent. After absorbing water, they swell up and fill their stomachs. Dogs don't feel hungry, so they naturally don't eat. If it is a natural sponge, you don't use tubes very much, because natural sponges are actually simple multicellular creatures, which are a bit like paramecium. But remember to supplement nutrition. If it is an artificial sponge, it is best to go to a pet hospital as soon as possible. Anyway, the health of dogs is the most important.