Moo Moo

Cows are a species of animals in the Mushroom Planet and also the real world. In the Super Mario Bros. Super Show! episode, "Mario and the Beanstalk / Bats in the Basement" Mario and Luigi had to get Gold Coins for the Mushroom Kingdom Orphanage, so they decided to sell Princess Toadstool's pet cow, the Royal Cow to Dealin' Delbert. Delbert wanted to trade one of his many cows with Royal Cow but the Mario Brothers wanted money. They instead traded Royual Cow for Garbanzo beans.

Cows can be seen in the background of Mario Kart 64 and Mario Kart DS course named Moo Moo Farm. In Mario Kart: Double Dash!!, in Mushroom City, a truck has a cow on it, with letters saying "Moo Moo Farm" on top of it.

Kamek mentioned a cow in Mario & Luigi: Partners in Time, on Yoshi's Island, before the battle with Kamek, Baby Bowser is eating too much Yoshi Cookies very fast and then starts choking. As Baby Bowser chokes, Kamek then tells him to drink some milk from an "evil cow".