Is hog a proper noun

No, the noun 'hog' is a common noun, a general Word for a domesticated swine or any of various animals related to the domesticated swine.

A proper noun is the name of a specific person, place, or thing; for example:

• Piglet (Winnie the pooh) or Porky Pig (Looney Tunes)
• Hog Mountain Road, Jefferson, GA
• The Hog & Bull (restaurant), Gloucester City, NJ
• Bush Hog Rotary Tillers

Example common noun in a sentence: "Bob loved raising farm animals, and he had a special love for his pet hogBrandon."

Example proper noun in a sentence: "The wrestler always snorted like a pig before he attacked so most people called him 'The Hog'."