Abstract
A new management programme for improvement of hatchability and reduction of transmission of bacterial potential pathogens from breeders to hatchery products was applied on a Saudi Arabian poultry farm. The technical changes included better nest engineering, improved cleaning of hatching eggs and better criteria for selecting eggs for incubation. The new nests led to a change in laying behaviour with 86.6% of eggs layed in nests which was significantly higher than was achieved previously. Bacterial penetration in dirty floor eggs was significantly higher than in clean nest eggs. The average hatchability was significantly higher for the flock under the new management than for the same age flock under the old management. The new management reduced transmission of paratyphoid organisms and Escherichia coli from infected breeders to their hatchery products. The old and new managements differed in the percentage of products infected with Salmonella.