Translation:Does the sheep drive?
Sorry, all sheepherders don't always use a dog. From the sentence, one does not know whether there is a single sheep or a flock of unknown number. Also, "Does the sheep drive?" does not mean what you may be interpreting it as. Out of context, one does not know whether or not the person asking the question simply means by "drive", i. e. can a particular sheep be herded or is it "stubborn" and one cannot "drive it". Those of us who grew up on farms and ranches may interpret this sentence different from the person who has lived in a town or city and learned everything from books, TV, etc.
The verb ending ~느냐 already determines that this is an interrogative sentence, a question. This is probably the reason the interrogation mark (?) is left out.
That said, punctuation marks should always be used for clarity and consistency. Just imagine for a moment if this sentence had a "요" ending ...
In Korean, the type of a sentence (declarative, interrogative, propositive, imperative...) is usually defined by the ending of the final verb.
In this example, "(V)느냐" (archaic form of "(V)니") indicates that the sentence is a question. There is no real need for a "question mark".
It's worth noting that punctuation marks only made their way into the Korean language in the late 19th century partly to facilitate reading and understanding for non-natives.