pig, hog
豬 centers on the animal pig or hog, referring to the domesticated swine.
豬 combines 豕 (pig) with 者, which likely contributes the sound. The character is an older form of 猪, with 豕 representing the pig more explicitly.
The left side 豕 is a pig, and the right side 者 looks like a person. Imagine a person leading a pig to market.
For チョ, picture a pig named Cho who loves to roll in the mud: Cho -> チョ.