The Breed game is definitely an abandonware since many years ago already, so you can find and download whole the game from multiple file sharing sources online, both CDV and Xplosiv editions are available in many sources.

Here are the links for the singleplayer demo as there is nothing wrong with sharing them at anywhere.
http://www.gamespot.com/breed/downloads/6085031/
http://www.gamershell.com/download_4426.shtml
http://www.strategyinformer.com/pc/breed/demo/853.html

If you still don't have the whole game, you can try this singleplayer demo of a single demo mission and decide whether you like the game and wish to gain the complete version with 18 missions and multiplayer.