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

Table 5 Replication in ducks of NDV after inoculated intranasally ^a

Virus replication on 3 DPI(log₁₀EID₅₀/g)^bin:	Strains
Virus replication on 3 DPI(log₁₀EID₅₀/g)^bin:	SS-10	NH-10
Heart	ND^c	1.58 ± 0.14
Liver	ND	ND
Spleen	3.58 ± 0.14	3.58 ± 0.14
Lung	2.58 ± 0.14	2.50
Kidney	2.17 ± 0.95	2.08 ± 1.01
Brain	1.58 ± 0.14	ND
Trachea	2.00 ± 0.66	2.00 ± 0.66
Small intestine	2.75 ± 0.43	3.42 ± 0.88
Bursa of fabricius	3.83 ± 0.38	3.50
Thymus	4.08 ± 1.01	4.17 ± 0.95
Pancreas	2.17 ± 0.95	1.67 ± 0.14
Cecal tonsils	2.67 ± 0.14	2.58 ± 0.14

^aTwo-week-old ducks were inoculated intranasally (i.n.) with 10⁶ EID₅₀ of each virus in a 0.2 ml volume; three ducks in each group were euthanized on 3 DPI, and virus titer was determined in samples of heart, liver, spleen, lung, kidney, brain, trachea, Small intestine, bursa of fabricius, Thymus, Pancreas and cecal tonsils in eggs [17].
^bFor statistical analysis, a value of 1.5 was assigned if the virus was not detected from the undiluted sample in three embryonated hen eggs. Virus titers are expressed as means ± standard deviation in log₁₀EID₅₀/g of tissue.
^cNo detected.