Table 4. Summary of vaccine efficacy results in SPF chickens

Group	Gross lesions		Histological lesion score		Virus detection rate		Mean bodyweight gain (g) at days post inoculation (DPI)
	HN	HP	Liver	Heart	Liver	CT	3	5	10
A	0/91)	0/9	0.22 ± 0.44a	0.22 ± 0.44	0/9	6/9	26.2	30.7	68.3
B	0/9	0/9	0.22 ± 0.44b	0.22 ± 0.44	0/9	0/9	28.3	27.6	80.6
C	5/9	0/9	2.11 ± 0.78ab	0.55 ± 0.72	6/9	8/9	−6.5	1.0	51.8
D	0/9	0/9	0.00 ± 0.00	0.00 ± 0.00	0/9	0/9	29.2	21.2	71.3

Positive chicken number / tested chicken number.
The statistically different values (p<0.05) were observed between groups.
SPF, specific-pathogen-free; HN, hepatic necrosis; HP, hydrppericardium; CT, cecal tonsil.