11. The duodenum, has a dark red colour and ramiform blood
vessels prominating under the serous coat, and sometimes,
haemorrhages are seen through the intestinal wall.
16. The spleen of infected birds is typically enlarged, haemorrhagic, crumbly, motted or marble-like. The
aetiological agent of HE is an adenovirus of group (type) II (HEV). The viruses or marble spleen disease in
pheasants (MSDV) and avian adenvirus splenimegaly (AAS) that are serglogically similar, beling to the
same group.
18. The liver is enlarged, crumbly and mottled with multiple haemorrhages, varying from
petechiae to ecchymoses. Dead birds are in a good condition, with pale skin. Once having
appeared in the farm, the infection is often recurring in other flocks. The HEV infection in
turkeys results in a transient immunosuppression and consequently, a secondary E. coli
septicaemia