Section 20. For the purpose of supervising the production of milk, any five or more registered physicians may form a corporation under this chapter. The members of the board of health of any town where such corporation is formed shall be ex officiis members of the corporation. At least one member of said board of health shall be a member of the board of directors thereof.

For the purposes of this section and sections twenty-one to twenty-five, inclusive, the word “milk” shall include goats’ milk.