Breedables Guide For Second Life
From Second Life Wiki
Breedable Animals Guide For Second Life
One of the most popular pastimes in Second Life is the caring for, feeding and breeding of virtual animals in Second Life. Over the years these animals have developed and a whole community of breeders and traders has emerged. Some players become so good at breeding animals that they are able to earn linden dollar profits from the buying and selling of them.
Most aptly described as squirrel type creatures, Snuffles are a breedable animal in Second Life with a thriving secondary market for the breeding and trading of Snuffle Burrows.
Amaretto Ranch Breedables released Amaretto Breedable Horses in Second Life in September of 2010 and very quickly became a leader in the breedables industry. Amaretto Breedable Horses are an interactive breedable that you can pet, ride, race and breed based on genetics. Amaretto Breedable Horses have a large secondary market for breeding, studding, racing, selling, trading and much more. The Amaretto Horses Main Store is located here
Amaretto Ranch Breedables released its 2nd breedable, Amaretto Breedable K-9s in Second Life in August of 2011. Amaretto Breedable K-9s are an interactive breedable that you can walk, play with and breed based on genetics. Amaretto Breedable K-9s also have a secondary market for breeding, studding, selling and trading. The Amaretto K-9s Main Store is located here.
Amaretto Barnyard Birds
Amaretto Ranch Breedables released its 3rd breedable, Amaretto Barnyard Birds in Second Life in May of 2012. Amaretto Barnyard Birds are an interactive breedable that you can hold and breed based on genetics. Amaretto Barnyard Birds have a secondary market for breeding, studding, selling and trading. The Amaretto Barnyard Bird Store is located here. Amaretto Ranch Breedables Barnyard Bird Main Store Amaretto Ranch Breedables Main Website
BioBreeds Dogs are the most realistic breedables in Second Life. BioBreeds launched in February of 2011 and prides itself on being a leader in innovation in the breedable community. The dogs respond to commands, breed, hunt and interact with BioBreeds horses. The Biobreeds genetic system mirrors real life. BioBreeds also provides a system for the owners to create unique attachments. BioBreeds users have built a strong secondary market, selling not only their dogs with unique traits, but also attachments, snacks, pets and other dog related items. You can view the existing traits on the website: 
BioBreeds Pal Ponies
BioBreeds Ponies were released in November of 2011. BioBreeds Ponies are a realistic looking ridable pony that follows commands, breeds and interacts with its owners and BioBreeds Dogs. Like the BioBreeds Dogs, an owner can create their own unique attachments. Its genetic system, and the rare traits that it produces, has spawned a strong secondary market for its breeders. You can view the existing traits on the website: 
BioBreeds Exotics introduced fantasy into the BioBreeds line of breedables. The ridable Exotics follow commands, breed, interact with their owners and also with Biobreeds Dogs. Like the BioBreeds Dogs, an owner can create their own unique attachments. Using the same genetic system as the BioBreeds Ponies, an owner can choose to crossbreed the Exotics with BioBreeds Ponies, infusing the Ponies traits into the genetic system of the Exotics, and vice versa. You can view the existing traits on the website: 
CritterBreeds are a variety of breedable pets for all ages.
The Main Store is located here.
A Fantasy Dwarf Community Building Game.
Dwarfins create their own community by crafting new Dwarfins from stone, building their own homes and interacting with items around them. The game allows you to decide how you want to play, you can work on creating ultra rare Dwarfins, focus on building your own village filled with peasants, farmers and vikings, or even a kingdom of kings, queens and jesters.
The Fennux Fennux are breedable pets that feature dueling, crafting of adapted Fennux with rare coats, community events and more. You can walk your Fennux, wear them on your shoulder, carry them around, feed them, breed them, and even duel your friends (or enemies). Come see The Fennux in-world by visiting the main sim location today!
Online market for Fennux: Fennux Market.
Gaia Breedables Website Gaia Breedables created the Gaia bird for users to enjoy, play and relax with as they watched their birds grow from chicks to full grown adults and breed new baby birds. It took 2 years with the assistance of the whole team to develop the Gaia's into what you see now, with many more plans for the future. Gaia Breedables are dedicated to the development of the Gaia birds and all aspects of Gaia Breedables. We will be looking forward to future releases and updates
KittyCatS are highly interactive cats that can be petted, cuddled and held. Owners and non-owners alike can interact with the adorable cats. KittyCatS are the first to take breeding OUTSIDE of SL with their KittyCatS Cattery. The Cattery is is a section of their website thus making breeding available to internet browsing devices, such as iPads.
KittyCatS won the Avi Choice Award 2012 for Favorite Breedable in Second Life.
Krafties are fantasy based creatures with an interesting backstory. They are the center of a free, in depth MMORPG type game in which the players can battle creatures and other players, catch new creatures and then combine them with many varieties of elemental souls, craft and enchant powerful items, and much much more. There are many species of creatures to choose from, all with different strengths and weaknesses. Visit the Krafties Island to start the journey for free.
Meeroos are a fantasy animal somewhat resembling a meerkat, with an elaborate backstory of their mythological origins. The first chapter of the story introduced the ground-based diurnal Meeroos, the second chapter introduces nocturnal Meeroos who emerged from caverns.
There is a third-party market for Meeroos: Meeroo Market.
Mossms are fun and zany space creatures that have come to our world to gather certain resources that appear to be in short supply or no longer exist in their space communities.
In order to mate, Mossms must return to space. Of course, space travel and the courting ritual both require resources. In other words, your Mossms will need to work for a living!
Mossms are incredibly interactive. Mossms know when an avatar is near and will respond to the avatar's presence. In addition, Mossms interact with other Mossms as well as their surroundings.
Mossms have a complex DNA system. Each newly born Mossm possesses genetics from its earliest ancestors. In addition, space exploration can cause genetic anomalies. The end result is an extensive array of possible breeds just waiting to be discovered.
Mossms are new to SL, arriving on scene in mid 2013 and are the first breedable to make use of several new SL technologies including: mesh, static pathfinding, keyframe movement and ray cast.
There is a fishing game associated with the breedable, as well as a 'tanking' system which can be used to build custom tanks that Oceania Breedables creatures can detect the boundaries of while swimming.
Odyssey came to Second Life in December of 2011 as the first low prim, low scripted, asexual pet in Second Life. There are over 100 different mythical seahorses of the deep, which provide meaning different breeding aspects to the user. There are one of a kind vendors to help our member sell eggs, and racing has been introduced to the mix.
Pufflings are small stylized birds which can be raised and bred for rare traits using similar genetic breeding principles as the other Ozimals product, bunnies.
Papillons are a collection of breedable butterflies, dragonflies, fireflies and plants. All the various insects and plants interact, along with accessories, to create an interdependent ecosystem. There is also an optional Adventure Game that can be played with the flutters.
Pet Peddlers was released in Dec. 2010 as the first shape changing breedable. All of Pet Peddles fish and seahorses (released Spring 2013) look like the real life version of that species. Pet Peddlers uses a unique predator system that allows you to load a food bowl and feed your predators with unwanted or breed out fish and seahorses. At present there are over 150 current fish breeds and 26 current seahorses. Pet Peddlers also has fishing game in beta now that will be released in the near future.
Wildwood Kitties are a type of breedable cat.
External Articles & Sites
Lawsuits between Ozimals and Amaretto have been in progress since 2010. Wikipedia has an article on Amaretto Ranch Breedables, LLC v. Ozimals, Inc.
Make your own open-source breedable pets with a tutorial by Ferd Frederix.