Related Clues:

• Pigpen comment
• Sound of swine
• Expression that may come from pen unable to write?
• 'Old MacDonald' sounds
• Sanction to restrict home producing beastly sound
• Sow's greeting
• Porker's grunt
• Hog holler
• "Sooey!" comeback
• Noise a pig makes
• Shoat shout
• Cow sound in 'Old MacDonald'
• Noise from a pen unable to write?
• Old material for writer it might make sense to hog?
• "Old MacDonald" sound