Cisapride, metoclopramide and emeprid are all gut stimulants so if you can get hold of one of them, one is all you will need. You can't give piggies more than one of them.
Ranitidine as far as I know is for bloat but I'm not completely sure as I have no experience using it, someone else on the forum may have more knowledge on this. Also be careful giving him dog probiotics as my vet says they are different to the small animal one. However, if it has the same things piggies need in them it should be ok.
I'm pleased to hear he is at least developing mucus poops, this also happened with Dexter a few days after his surgery. Dexter is doing a bit better, day by day but noticed today he was bleeding a little and looks like he's caught his wound so I'm a bit worried but hopefully he will be OK.
Awww bless him, he is beautiful and so lucky to have a caring owner. You really are doing your best for him and you should be proud of yourself. What is his name?
Here is a picture of Dexter's mucus poops, are your piggies similar to this?
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