Efficiency of Performance Testing in Poultry

TO MAKE efficient performance comparisons between crosses or strains of chickens it is important to know how sample size, testing location, year of test and the amount of trapnesting influence the differences observed. A knowledge of these factors as they influence variations in egg yield and other performance traits is of increasing importance to the breeder today whether he produces inbred-hybrids, strain-crosses, breed crosses or pure strains. In fact, it would be valuable to take these factors into account in a closed flock breeding program in order to carry on more efficient sire testing. Also, with the increasing emphasis placed on random sample testing of commercial poultry today, it is evident that much more needs to be known regarding factors which influence the reliability of strain comparisons. A question of special significance in a testing program is the importance of genetic-environmental interactions. For example, will a variety that is superior …