Minecraft wiki entry for Cow, associated text: Cows are visually based on the Norwegian Red cattle.
Cows in the PC Gamer Minecraft Demo are branded with a 'PCG' logo on their side.
Notch stated in a Tumblr post that all "breedable" peaceful mobs displayed traits of both genders and could breed with any other individual of their species.[1] This applies to cows as they have horns and give milk (although, in some breeds, female cows also have horns).
Cows prefer to stay on lit places to dim places.