Frank J. Wilstach, comp. A Dictionary of Similes. 1916.
Grunt
Grunt like a bear when he is a-moaning.
—Ulpian Fulwell
Grunting like some pounded animal.
—Maurice Hewlett
Grunted like a pig under a tub.
—John Lyly
Grunts like a hog.
—Christopher Marlowe