Translation:The dog likes you because you have food.
Yes, but you'd have to change the word order: Du har mat, därför tycker hunden om dig.
därför att is a subjunction (which joins a clause and a subclause) but därför is just an adverb that can be used to join clauses, therefore both clauses are main clauses and will use the V2 rule.
Ok, I'm sorry: I see that this has been addressed, but I still don't understand: "eftersom" is 'because' and/or maybe 'since.' (To me, at this point, it's only incidental that it can start a sentence.) "Därför att" is also 'because,' but I can't tell when one is in/appropriate, or the other. I gather that 'därför,' by itself means "so, therefore." Can someone explain a rule about when to use 'eftersom' and when to use 'därför att?'
Not quite. "Feed", when used to mean giving an animal sustenance, is generally reserved for animals bred for commercial/practical purposes. I might give my beef cattle "feed", but I'd give my cat "food"; I might give my hens "feed", but I'd give my pet mouse "food". I would never say I give my dog "feed" unless I was fattening him to be part of a good Chinese meal!
It is only a stylistic difference, a spelling difference. 'Dig' is how it is taught in school. 'dej' is spelling as it sounds. More high brow authors keep the 'dig'-spelling, I keep it just by habit. Popular writers (low-brow), e.g. writing detective stories/police novels, will usually prefer 'dej'.