Cow ("Bos taurus") remains discovered at the Olmec Site of Lay Joya

 The following comes from:

Tanya M. Peres, Amber M. VanDerwarker, and Christopher A. Pool, "The Zooarchaeology of Olmec and Epi-Olmec Foodways Along Mexico's Gulf Coast," in The Archaeology of Mesoamerican Animals, ed. Christopher M. Götz and Kitty F. Emery (Archaeobiology 1; Atlanta: Lockwood, 2013), 106