If your dog previously ate from their bowl then it could be that they have made a negative association with the bowl and that's putting them off. You need to rule out pain and discomfort, so check his teeth are in good condition and that he isn't having difficulty bending or leaning into the bowl.
Why my dog only eats from the floor?
As for eating off the floor, many dogs take food from their bowl and drop it onto the floor or take it to another location to eat it, so there is something instinctive about the behavior and nothing to worry about if he does this.
How do I get my dog to eat out of his bowl?
Try pouring a little chicken broth or stock in the bowl to encourage him to eat from the bowl and give him lots of praise when he decides to go ahead and eat. Keep food availability to a minimum, say for around 20 minutes before picking up the bowl. Keep trying until he is ready to eat the minute you put the bowl down.
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