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results in a variety of conditions, ranging from subclinical infections through respiratory disease with low mortality to severe disease with high mortality. Various combinations of the 16 hemagglutinin (HA) and 9 neuraminidase (NA) sub-types of AIV have been isolated from avian species.1,8 Highly pathogenic AIV (HPAIV) subtypes such as H5 or H7 have spread throughout many countries since 1997, and outbreaks of HPAIV have caused serious economic losses in the poul-try industry worldwide. Low pathogenic AIV (LPAIV) sub-types H5 and H7 are notifiable AIVs (NAIVs) because they can mutate to HPAIVs both in the field and in the laboratory setting.3,9,10,17 The hemagglutination inhibition (HI) assay is a useful method among the various diagnostic methods available for detecting and measuring AIV subtype-specific antibodies