. 2010 Jan 21;149(1):86–94. doi: 10.1016/j.virusres.2010.01.006

Table 2.

Experiment 3: dose titration of QR448(a) spray treatment in 2-week-old specific pathogen free chickens 2 h before or 2 h after challenge with pathogenic IBV.

Treatment^a	Treatment 2 h before challenge		Treatment 2 h after challenge
	Number of birds with clinical signs/total (average score)^b	Histopathology scores^c	Number of birds with clinical signs/total (average score)	Histopathology scores^c
Undiluted + IBV	6/10 (1.6)	2.43^a	3/10 (1.4)	2.52^a
1:5 + IBV	6/10 (1.6)	2.58^a	6/10 (1.7)	2.55^a^,^b
1:10 + IBV	3/10 (1.3)	2.68^a	7/10 (1.7)	2.45^a
1:20 + IBV	4/10 (1.4)	2.72^a	6/10 (1.6)	2.45^a
1:40 + IBV	8/10 (2.0)	3.05^b	5/10 (1.8)	2.44^a
1:80 + IBV	6/10 (2.0)	3.18^b	6/10 (2.0)	2.45^a
1:160 + IBV	4/10 (2.0)	2.95^b	9/10 (2.8)	2.67^a^,^b
1:320 + IBV	5/10 (2.2)	2.89^b	6/10 (2.5)	2.74^a^,^b
1:640 + IBV	7/10 (2.7)	2.83^b	9/10 (3.7)	2.78^a^,^b
1:1280 + IBV	8/10 (3.2)	3.45^c	8/10 (3.2)	2.95^b
IBV	9/10 (3.7)	3.21^c	7/7 (4.0)	3.00^b
Undiluted	0/10 (1.0)	1.10^d	ND^d	1.10^c
Negative control	0/10 (1.0)	1.05^d	ND	1.05^c

Treatment = QR448(a) sprayed undiluted or diluted at a dose of 1 ml/bird followed by challenge with 1 × 10^4.5 EID₅₀ of pathogenic IBV, Mass41 strain.

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.

Tracheas were scored for epithelial hyperplasia, lymphocyte infiltration, and epithelial deciliation with 1 being normal and 4 being severe. Histopathology scores within a column with different superscripts are statistically different at p ≤ 0.05 (Kruskal–Wallis test).

Not done.