In theory any modern composite breed of known ancestry could be recreated by crossing the foundation breeds used to create it. There is nothing wrong with this concept, it's sound, good, theoretically a practical approach.
However, this recreation should not be done lightly! In my opinion, it would best be done if you did not have the breed in your country and no practical way to import it, or, the breed was extinct. The problem with a recreation is that the Malay and the Leghorn of yesterday are NOT the same as they are today, and you will not be able to get a good Belgium Game at all. Good Malay and good Leghorns are expensive and not easy to come by, especially the Malay. If you would use hatchery stock birds to do the remake, you will end with birds probably worse than the current hatchery Kraeinkoppes. Any type of project like this would be best if it used the best possible examples of the breeds. Even if you could find good Malays, for the cost of one, you could get a ton of chicks from a hatchery. Malay are very very expensive, the good ones. The ones from Ideal are not worthy of the name. We already have kraienkoppe here in the USA. Why recreate them when we have them already? Two hatcheries carry them, and several breeders as well, although, I must add all stock is related. They may not be the best, but they are real Kraienkoppes. Why not get some chicks from both hatcheries, select the best from each, cull down really hard, and cross the 2 lines? Then, if possible, pick up a few breeder birds. If you don't think you are making progress after a few years, get a great Malay and or Leghorn, and start a grading process. That is, cross a pure Kraienkoppe with either breed, then, select the best chicks, and cross them back to the kraienkoppe. Do this for 3-6 generations, this process should help fix any problem you think there is without recreating the whole breed.
Yes, using a BB Red Old English/American game as part of the process might be as good if not better than using a Leghorn.
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