Table 1.

Frequency by type and distribution of histologic lesions in the proventriculi of broiler chickens with transmissible viral proventriculitis.

Proventricular histologic lesions	Frequency
Lymphoplasmacytic and histiocytic infiltrate affecting >50% of the glands (marked)	1/73 (1)
Ductal metaplasia of the glandular epithelium	11/73 (15)
Interglandular mild number of follicular aggregates of lymphocytes	12/73 (16)
Lymphoplasmacytic and histiocytic infiltrate affecting 25–50% of the glands (moderate)	13/73 (18)
Lymphoplasmacytic and histiocytic infiltrate affecting up to 25% of the glands (mild)	21/73 (29)
Glandular epithelial necrosis	22/73 (30)
Glandular ectasia	24/73 (33)
Moderate to marked number of follicular aggregates of lymphocytes	24/73 (33)

Numbers in parentheses are percentages.