Moo Moo

Moo Moos (also generically referred to as cows) are  that appear mainly in farm-based courses in the Mario Kart series. In some appearances, they act as obstacles for drivers. They wear blue collars with golden bells hanging from them.

Mario Kart 64
Moo Moos can be seen in the background of the Mario Kart 64 course named Moo Moo Farm.

Mario Kart: Double Dash!!
In Mario Kart: Double Dash!!'s Mushroom City stage, a truck advertising the Moo Moo Farm course features a Moo Moo.

Mario Kart DS
Moo Moos once again appear in the background of the Retro Course.

Mario Kart Wii
In Mario Kart Wii, Moo Moos serve as obstacles in the course Moo Moo Meadows. When hit, they cause the player to spin out. While the ones seen up close use full models, some in the distant background reuse flat textures from Mario Kart DS. A truck in the Moonview Highway course also has a picture of a Moo Moo printed on it with the text "Moo Moo Dairy".

Mario Kart 7
Two Moo Moos make a small appearance in Mario Kart 7 on a sign in the course, which reads "Moo Moo Dairy".

Mario Kart 8 / Mario Kart 8 Deluxe
Moo Moos return in Mario Kart 8 and Mario Kart 8 Deluxe with the return of the Moo Moo Meadows track, this time with Moo Moos of other colors, such as solid black or brown. Also, in Toad Harbor and the game's rendition of Toad's Turnpike, there are advertising trucks and signs with Moo Moos on them. There is also a sponsor known as Moo Moo Meadows Milk. In this game, Moo Moos appear in four different colors; white with blue spots, white with brown spots, black, or brown.

Mario Kart Tour
Although Moo Moos themselves do not appear in Mario Kart Tour, the Moo Moo Meadows Milk sponsor returns in several courses in the game, and a Moo Moo Mii Racing Suit is available as of the Animal Tour.

Mario Kart Live: Home Circuit
In Mario Kart Live: Home Circuit, the Windmill Meadows features some Moo Moos as obstacles.

Mario Party 3
In Mario Party 3, Moo Moos appear in the background of Fowl Play.

Mario Party: Island Tour
In Mario Party: Island Tour, Moo Moos appear on the Perilous Palace Path board as decoration on the board.

Mario & Sonic at the London 2012 Olympic Games
Moo Moos reappear in Mario & Sonic at the London 2012 Olympic Games on Moo Moo Meadows as obstacles in the Dream Equestrian event.

Yoshi's Woolly World / Poochy & Yoshi's Woolly World
Despite Moo Moos not appearing in Yoshi's Woolly World and Poochy & Yoshi's Woolly World, Moo Moo Yoshi is available as an unlockable Yoshi pattern which resembles a cow.

Yoshi's Crafted World
In Yoshi's Crafted World, the Moo Moo Meadows Milk sponsor from Mario Kart 8 makes various cameo appearances on the cartons and signs in the background of the flip side of Rail-Yard Run and Go-Go Yoshi. As first seen on the front side of Rail-Yard Run, there are also five cardboard Moo Moo crafts, which serve as Coal Blockafeller's first souvenir request.

Nintendo Badge Arcade
Moo Moos appear as badges in Nintendo Badge Arcade that the player may collect and decorate their Nintendo 3DS HOME Menu with. They are a part of the Mario Kart 8 set of badges.

Minecraft
In the Super Mario Mash-up in Minecraft, the traditional Cow's design from Minecraft is replaced with the Moo Moo design found in the Mario titles. Red Moo Moos with mushrooms on their back replace Mooshrooms.