Question about breeding.

[Darius123]

Let s say that, i have a pure breed brahma, i cross him/her with lets say cochin, the off springs are going to be crossed with only brahma for lets say 20 more generations. The last off springs will not be a pure breed brahma, cause in their ancestry there was the brahma x cochin cross?

 

[wolfwalker]

By your definition Brahma are not Brahma as it took many differing breeds to create the Brahma's.

That said, you are ignoring one important factor.

By breeding half Brahma birds back to Bahama's you will eventually breed the Cochin out, especially over 20 generations. Most new chicken breeds are established, as in breeding true, in 6-8 generations.

Dealing with critically endangered poultry you end up dealing with issues due to inbreeding. One of the ways to correct this issue is to outcross and breed the progeny back to the inbred line and introduce genetics to correct the flaws. after selecting offspring for 6 generations it is accepted that the line is back to breed standard and can be called by their breed name again without issue.

Of course this is a two edged sword as if you are not careful with the outcrossing you can activate lethal genes and destroy the line completely within a generation or two.

There have been a lot of old timers who are fantastic at rescuing breeds that have not passed on their knowledge and are dying off and we lose that knowledge and have to constantly reinvent it due to no one bothering to write it down.

So before we go down the rabbit hole metaphorically speaking I think I have answered your original question on if you cross a Brahma with a Cochin if after twenty generations of breeding the progeny back to only brahmas if they are considered pure bred Brahma and the answer is yes they are as long as you select future generations for Braham looks.