Breeding



Breeding is a game mechanic that allows animals of the same species to breed with each other to make new animals. Each type of "domestic" animal has a food item used to lead and breed it. (There are a couple of special cases, described under "Mechanics" below.) Animals will follow a player holding its food (once it notices the player), and will continue following the player until it is out of range, the player stops holding the item, or it begins the breeding process. If two nearby animals of the same species are fed, they will spawn a single baby animal of their type. Any animal may only breed once per item given (two parents must be fed to breed), and will be unable to breed for some time after. Note that animals are uninterested in food lying on the ground.

Using wheat or other items (carrots, and seeds) to breed animals that give food (cows, mooshrooms, pigs, chickens) is a way of getting more efficient food than bread or carrots.

Mechanics
The specific items for each breedable animal are as follows:

One item per parent is needed to breed a single baby. Each animal which is fed its food will enter "love mode", preparing to breed with another animal that is in "love mode". Animals that are "in love mode" emit hearts constantly and will path find towards animals up to eight blocks away of the same species that are also "in love mode." The two animals will "kiss" for about two and a half seconds, and then a baby animal of the same species spawns either in between the parents or on the same blocks as the parent that was spawned first, which ends love mode for the parents. Once the parents breed they also drop a small amount of experience. They will not be able to enter love mode again for 5 minutes. However, they can still be herded with the appropriate material, as can the baby.

After the baby animal has spawned, it will follow its parents for 20 minutes before growing to full size. The growth of baby animals can be slowly accelerated using the animal's breeding item. Each use takes 10% off the remaining time to grow up, with the exception of horses where different breeding items speed up the growth by different amounts.

When sheep are born, they will usually be the color of one of their parents, chosen at random. However if the parents have 'compatible' colors (meaning that their corresponding dye items could be combined into a third dye), the lamb will be a mix of the parents' colors (see Wool Dyes). This holds true even if one or both of the parents have just been sheared before breeding and have not yet grown their coats back. This is a handy way to obtain wool of a color for which you do not have a dye.

Villagers
Villagers do not have a food item; they will breed of their own accord (and in their own time) depending on the available houses, or at least "registered doors". (See the village page for full details.) When they breed, they will produce a smaller Villager but unlike most baby animals, these don't have big heads, similar to cats. Baby Villagers will run around the village and will "play" tag. In the new 1.8 update, Villagers need Trading or food from farms to breed. A baby villager killed by a zombie may produce a Baby Zombie Villager, depending on difficulty.

Breeding formula
A player may want to know how many mobs they will need in their farm to reach a certain goal, for example: to make a full-powered enchanting table with bookshelves (45 leather needed) or for full leather armor (24 leather), in case you have cow farm. So there is a formula to calculate how many mobs you will need to have at your farm, by the starting number and if you wait until all the mobs become mature (this does not apply to villagers):

where Xn is the number of mobs at generation n.

Alternatively, if you start with X mobs and want to reach a population of at least Y, it can be achieved in  generations.

Baby animals
Baby animals are smaller variations of their parents, having small bodies, relatively big heads, higher pitched sounds, and faster walking speeds. They do not drop resources or experience if killed, lambs cannot be sheared for their wool, and calves and mooshroom calves cannot be milked. Baby animals will follow one of their parents until they grow up. (If the parent dies or there is none, they will pick a nearby adult of their kind.) Tame puppies and kittens will follow their owner if the parent is absent or sitting, and puppies will attack aggressive mobs just as a mature dog would. When killed before becoming an adult, baby animals (excluding baby zombies and baby zombie pigmen) drop nothing.

Baby animals grow into full sized animals after twenty minutes (one game day, beds notwithstanding). Their growth can slowly be accelerated using the animal's breeding item, where each use takes 10% off the remaining time to grow up. There are a few variations:
 * Sheep can grow faster if they eat grass.
 * For dogs (tamed wolves), the puppy does not gain its full health automatically (even when it grows to full size), but must be fed to increase its HP.
 * Foals (baby horses) can be fed to speed their growth.

Trivia

 * Animals of the same species are able to breed with each other regardless of whether they are a parent to the animal they are bred with.
 * Baby cows or sheep will follow you if you are holding wheat, and the wheat can be fed to them to speed up their growth.
 * Baby wolves seem to be naturally attracted to the player.
 * Using the spawn egg of a mob which has baby variants on that mob will spawn the baby variant. However, this will not work on zombies or zombie pigmen before TU18 was issued.
 * When sheep are bred in the Pocket Edition, the lamb is either one sheep's color or the other - combination colors don't work.