Puppy is 10.5 weeks - she's not my first dog but the first I've had from a puppy. She's been on Beta Puppy since weaning, and has always had fairly soft poo, Mr Whippy-style (sorry TMI!). As she has been happy and healthy otherwise, I've not been too worried. However, yesterday morning I came downstairs to a large brown puddle on the floor from where she'd clearly had an upset stomach overnight. Behaviour was completely normal and she bounced around very happy to see me. I gave her scrambled egg instead of kibble for breakfast, and have been alternating eggs and chicken with rice since then. In herself she is completely normal - alert, playful, hungry, etc, but her poo is still pretty liquid.
With an adult dog, I'd give it another couple of days treating at home before calling the vet. Where would you draw the line with a puppy though? Other than a stomach upset she's absolutely fine, but thinking I might need to take her in tomorrow? I have a feeling it may be due to eating pigeon poo - I have a large tree overhanging my garden and she is permanently snuffling around in the grass under it...