Egg bound duck

[annray55]

One of my Muscovy hens appears to be egg bound. She seems to be straining to lay an egg but nothing happening. I noticed her acting this way last night and she is still at it now. I have tried giving her some food and water but she just turns away. There is some runny poo dribbling out but that I haven't seen her actually poop normally.
I have her sitting in a warm tub of water right now and I have been massaging her belly but to no avail. Does anyone have any other suggestions?

Thanks, Ann