As breeder of game fowl it is very important to maintain the bloodline that is tested and give you a high percentage of winning and championship in major stag derby like bakbakan and cock derby like world slasher cup. There are many ways used by game fowl breeders to maintain the bloodline of fighting cocks. The common is breeding of offspring back to parents or breeding of a full sister to full brother. For me that technic is good in preserving or maintaining a game fowl but I have another technic on how do I maintain a game fowl bloodline.
The method on how to maintain a fighting cock or game fowl bloodline is very important to a breeder. In my case I use the in-and-in method in maintaining my game fowl bloodline. In this method I did not mate offspring back to parents and mating full sister to full brother. What I did to maintain bloodline is I select my finest brood cock for example I would like to maintain my Roundhead bloodline, to do that chooses my best two hens for example a lemon and hatch. I breed these two hens to my roundhead brood cock and make sure to identify the eggs off two hens for example the egg of lemon is identified and also the eggs of hatch. When the eggs of a lemon hen hatches and later grown up I choose the best stag (50% roundhead and 50% lemon). And I also choose the best pullets produced by the hatch hen (50% roundhead and 50% hatch). To maintain the roundhead bloodline I breed the stag composed of 50% roundhead and 50% lemon to a pullet composed of 50% round head and 50% hatch. The result of that mating is an offspring with a high percentage of a roundhead. In that way you made to maintain your game fowl bloodline, in the example is the roundhead. You can apply this method to your own needs and on your own bloodline that you want to preserve or maintain.