Phylogenetic relationships and pathogenicity variation of two Newcastle disease viruses isolated from domestic ducks in Southern China

Table 4 Virus titers in cloacal and oropharyngeal swabs from chickens

Strains		Days post-inoculation (log₁₀EID₅₀/0.1 mL) ± SD^a
		3 Day		5 Day		7 Day		9 Day		11 Day
		Oropharyngeal swabs	Cloacal swabs	Oropharyngeal swabs	Cloacal swabs	Oropharyngeal swabs	Cloacal swabs	Oropharyngeal swabs	Cloacal swabs	Oropharyngeal swabs	Cloacal swabs
SS-10	Infected ^b	4.30 ± 0.51 (6/6)	4.5 (6/6)	2.67 ± 0.14 (3/3)	1.75 ± 0.43 (1/3)	-^d	-	-	-	-	-
SS-10	Contact ^c	2.50 ± 0.25 (3/3)	3.17 ± 0.63 (3/3)	3.42 ± 0.58 (3/3)	2.50 ± 0.75 (3/3)	1.75 (1/1)	1.75 (1/1)	ND^e (0/1)	ND (0/1)	ND (0/1)	ND (0/1)
NH-10	Infected	3.58 ± 0.20 (6/6)	4.04 ± 0.56 (6/6)	4.5 (1/1)	5.25 (1/1)	-	-	-	-	-	-
NH-10	Contact	2.42 ± 0.14 (3/3)	2.58 ± 0.14 (3/3)	4.25 ± 0.43 (3/3)	4.67 ± 0.88 (3/3)	-	-	-	-	-	-

^aFor statistical purposes, a value of 1.5 was assigned if virus was not detected from the undiluted sample in three embryonated hen’s eggs [17].
^bChickens inoculated with virus.
^cNaive contact chickens housed with those inoculated.
^dAll the chickens died at the end of the observation.
^eNo detected.