Table 2.

Viral gene copies detected in allantoic fluid and days of embryonic death by infection with different concentrations of wild and vaccine strains of TW2575/98

Viruses	Virus titer (10n EID50/0.1 ml)	Mean of viral gene copies (n × 109)/µl among 7 days	Mean days of embryonic death after DPI
TW2575/98w	4.7	14.0 ± 7.67a	5.0 ± 1.73
	3.7	12.6 ± 7.02*	5.7 ± 1.15*
	2.7	3.3 ± 4.18*	6.0 ± 1.73*
TW2575/98vac	4.7	46.2 ± 46.53	3.3 ± 1.15
	3.7	81.9 ± 51.14*	4.0 ± 1.00*
	2.7	30.3 ± 15.18*	3.0 ± 1.00*

DPI day post-inoculation

*Significant difference between wild and vaccine strains (p < 0.05)

^aMean ± SD