Possible Clues:

• Miner's small dog
• Depression the situation for a dog
• Line leaving coal mine
• Sheep gatherer
• Might an officer lie so doggedly?
• If the old king is about fifty-one it's enough to make him sheepish
• One works with those that are sheepish
• Sounds as if one's heard to be sheepish, perhaps
• Dogged enough to be sheepish at work (6)
• One will work with what's heard, by the sound of it