Oops, it doesn't look like 'visit a zoo day' is a national day..

Other days

healing

Healing Day
mean girls

Mean Girls Day
my little pony

My Little Pony Day
blanket fort

Blanket Fort Day
polyamory

Polyamory Day
offer

Offer Day
china

China Day
stud

Stud Day
kiss a ginger

Kiss A Ginger Day
book

Book Day