From everything I have heard and my own experience you can expect them to have no interest for 3-4 days or at least when the yolk sac is totally gone. And did you mean black worms? I think I would avoid blood worms if it was me....well that could be because I am deathly allergic to them but I also heard they arn't as good as black worms anyway. Oh and congrats on the pups they look awesome.