Related Clues:

• Sign of a pen problem?
• Barnyard cry
• Bull sound
• Chester White remark
• Sound on a 58-Across, perhaps
• Pen pal's protest?
• Swine sound
• Show scorn, in a way
• Pig's sound
• Quick shot
• Pigpen sound
• Nasal sound
• Swine squeal
• Sow's remark
• Reply to a pen pal?