Table 1.

Gross lesions in SPF chickens inoculated with IBV strains rYN-1a-aYN, rYN-1b-aYN and rYN.

Strains	Lesions	Days post-challenge (dpi)
		3	5	7	10	14
rYN-1a-aYN	Laryngeal hemorrhage	1/2 a	1/2	1/2	1/2	2/7 b
	Tracheal exudate/hemorrhage	0/2	0/2	0/2	1/2	0/7
	Renal enlargement/urate	0/2	0/2	0/2	0/2	0/7
rYN-1b-aYN	Laryngeal hemorrhage	2/2	2/2	2/2	2/2	4/5 c
	Tracheal exudate/hemorrhage	1/2	1/2	1/2	2/2	2/5
	Renal enlargement/urate	0/2	0/2	0/2	0/2	0/5
rYN	Laryngeal hemorrhage	1/2	2/2	2/2	2/2	5/7
	Tracheal exudate/hemorrhage	1/2	2/2	1/2	2/2	4/7
	Renal enlargement/urate	0/2	0/2	0/2	1/2	0/7
PBS	Laryngeal hemorrhage	0/2	0/2	0/2	0/2	0/7
	Tracheal exudate/hemorrhage	0/2	0/2	0/2	0/2	0/7
	Renal enlargement/urate	0/2	0/2	0/2	0/2	0/7

^aNumber of chickens exhibiting gross lesions out of the examined number of birds.

^bEnd of the observation period at 14 dpi.

^cTwo chickens died during the observation period.