Related Clues:

• Cooped up at Old MacDonald's
• Penned up
• Penned, as a pig
• Confined to a pen
• Kept in a pen
• Put in a pen
• Housed in a pen
• Like a pig in a pen
• Confined to a pig pen
• Pent up in a pigpen
• Kept in a pigpen
• Cooped up like pigs