What pathological changes are associated with sudden death syndrome in laying hens?

Pathological changes of sudden death syndrome in laying hens: affected hens show ovarian follicle hemorrhage, enlarged liver, congestion, and hemorrhagic spots, pulmonary congestion, cardiac dilation, and oviduct congestion and edema. A hard eggshell is often present; glandular stomach ulceration, perforation, or thinning of the glandular stomach wall, with brown fluid flowing from the glandular stomach papillae; intestinal hemorrhage and sloughing of the intestinal mucosa. The contents are grayish-white or dark brown.