Yes, CHOWSES is a Scrabble word!

Letter values in Scrabble US: C 3, H 4, O 1, W 4, S 1, E 1, S 1.

Is it a valid word?

CHOWSES is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

the imperial dynasty of China from 1122 to 221 BC; notable for the rise of Confucianism and Taoism
informal terms for a meal
breed of medium-sized dogs with a thick coat and fluffy curled tails and distinctive blue-black tongues; believed to have originated in northern China

Also: zhou dynasty, chou dynasty, chow dynasty, chow chow.

Not playable in Scrabble US: ZHOU, CHOU.