Your most valuable birds are ones which are good breeders. These birds should not be used for racing. Although they may be winners you could lose them and and also your future winners.
Good record keeping is key to early recognition of which the good breeding birds are. It is time consuming but will enable you to make the right decisions as to which birds to race.
Check your records often to make analyses of your birds. Keep records of all the progeny from a pair. Once you have found a good pair of breeding birds which have produced several winners build your own family around them.
There are a numner of systems available which can be used in breeding. These include cross breeding, line breeding and in-breeding.
Records of the pedigrees are important when buying birds and should show that winners were produced and that impossible gene patterns did not occur which would suggest mistaken or false records or possibly matings have occured with other birds.
It is easiest to cross breed birds whilst in breeding needs more care. Cross breeding is the mating of birds which have no relationship with the other for 5 generations or more.
Line breeding is said to occur when a pair are mated from different generations of the same line.
In breeding is used to concentrate desirable genes in a family. This system uses matings between closely related birds ie. father to daughter, mother to son, brother to sister. For inbreeding you need very good stock.The concentration of genes can also strengthen poor qualities if they exist as well as the good traits.
When inbreeding the sytematic culling of weaker birds is used to remove poorer gene characteristics and strenghthen the line, again the keeping of good records is important to identify weaker birds which lack speed or may have a less reliable homing instinct.
The strategy of inbreeding is to remove weaker variables from the line so the temptation to outcross should be resisted as this may introduce some unpredicatable elements.