Table 3.

Experiment 4: clinical signs^a in broiler chickens challenged with IBV at various times after treatment with QR448(a) at 1 day of age.

Treatment group	Challengeb times post-treatment
	2 h	4 h	6 h	12 h	1 day	2 days	4 days	7 days
QR448(a) + IBV	3/10 (1.3A)c	5/10 (1.5A)	0/9 (1.0A)	3/10 (1.3A)	0/10 (1.0A)	3/10 (1.3A)	1/10 (1.1A)	9/10 (3.6B)
QR448(a)	0/10 (1.0A)	0/9 (1.0A)	0/10 (1.0A)	0/10 (1.0A)	0/10 (1.0A)	0/10 (1.0A)	0/7 (1.0A)	0/10 (1.0A)
IBV	8/10 (3.1B)	8/10 (3.1B)	9/10 (3.6B)	9/10 (3.6B)	7/9 (3.3B)	5/6 (3.5B)	8/8 (4.0B)	8/8 (4.0B)
Negative controld	0/10				0/9	0/6	0/7	0/9

^aBirds were necropsied and clinical signs recorded 5 days post-challenge. Clinical signs consisted of watery eyes, tracheal rales, and mucus in the nares and the trachea.

^bEach bird was given 1 × 10^3.5 EID₅₀ of the Mass41 strain of IBV intranasally.

^cNumber of birds with clinical signs per total (average score). Clinical signs were scored as follows: 1 = normal, 2 = watery eyes or mucus in the nares, 3 = watery eyes and mucus in the nares, and 4 = watery eyes, mucus in the nares and tracheal rales. Average scores with different capital letter superscripts are statistically significant at p ≤ 0.01 (Kruskal–Wallis test).

^dClinical sign scores for negative control birds were all normal (1.0).