The National Poultry Improvement Plan (NPIP) was started in the early 1930's to coordinate state programs aimed at the elimination of pullorum diseases from commercial poultry. Pullorum is a bacterial disease of poultry that is transmitted from a hen to her chicks via the egg. By testing adult birds and eliminating disease carriers from the breeding flock, commercial chicken and turkey producers have eliminated this costly disease.

For more information on the National Poultry Improvement Plan:

http://www.aphis.usda.gov/animal_health/animal_dis_spec/poultryl