Egg-drop syndrome 76 in Danish poultry.

After a more general mention of Egg drop Syndrome 76 (EDS 76) an account is given of 3 cases of EDS 76 in broiler parent flocks. In all cases the animals involved originated from Ireland and were imported as day-olds, either directly from Ireland or via Sweden. Serological examinations indicate that the infectious agent has not previously been present in Danish hen flocks, but that it is presumably stationary in Danish flocks of ducks. In 2 of the 3 cases of EDS 76 animals from 2 different foreign firms were involved, and everything indicates that the infection has been carried by chickens from one of the firms and spread horizontally to the other. In the first case 12 weeks lapsed from the first to the last of 6 flocks in the same locality were attacked by SDS 76. An example is also given of trans-ovarial spread of EDS 76-virus to broiler flocks which at the age of 10--20 days were attacked by a disease similar to gangrenous dermatitis. In the course of the following few weeks an intensive rise took in the frequency of positive reaction to EDS 76. It is assumed that the EDS 76-virus has been of importance to the development of the said disease in these broiler flocks.