Evolutionary relationships were inferred using the neighborjoining
method (Saitou and Nei, 1987) with Kimura-2 parameters
(Kimura,1980). In the inference, HA sequences of some Indonesian
avian isolates dating from 2003 to 2006 available in the GenBank
database were included representing groups A, B, and C as formerly
proposed (Smith et al., 2006), i.e. Ck/Wajo/2005 (Group A; Acc. No.
DQ320933), Ck/BL/2003 (Group B; Acc. No. AY651321), and Tk/
Kedaton/2004 (Group C; Acc. No. DQ497664), as well as the first
official vaccine seed of Ck/West Java/2003 (Acc. No. KR078216).