Table 1.

Lesions evaluated and scored by histology

Trachea (upper and lower part)	Kidney
Loss of epithelial cells	Focal lymphoid cell infiltration
Degeneration of epithelial cells	Diffuse lymphoid cell infiltration
Lymphoid cell infiltration of the lamina propria	Degeneration of tubular epithelial cells
Depletion of mucus secreting cells	Lymphoid infiltration in the collecting duct or ureter
Heterophil exudate in the lumen
Hyperplasia of mucus-secreting cells	Gastrointestinal tract
Metaplasia of epithelial cells	Lymphoid infiltration in the glandular stomach
Hyperplasia of epithelial cells	Lymphoid infiltration in the small intestine
Lung	Reproductive tract
Bronchitis, mesobronchitis	Oophoritis
Focal lymphoid cell infiltration	Calcium deposition in the oocytes
Diffuse lymphoid cell infiltration	Lymphoid infiltration of the wall of the oviduct
Peribronchitis	Dilation of the oviduct
	Orchitis, epididymitis