WARNING !! I have heard from Ann who adopted the lovely scruffy Mojo from Cahors refuge last year. They had a nasty scare when Mojo started violently trembling and they thought he was fitting. A mad dash to the vet where they found out they he had eaten poison. The vet said that farmers are putting slug pellets down when they fertilise so it is easy for a dog to get the poison on their paws or drink it if the pellet has been rained into a puddle. So, if your dogs shows any symptoms, get him/her to the vet directly, any delay could prove fatal.
ps What could also prove fatal to humans (if I get my hands on them) is taking a dog back to the refuge in this freezing weather after they have known the comfort and warmth of being inside. For heaven’s sake couldn’t you wait just a week until the weather improves ?