Age based RFFIT findings reveal protective mRVNA titers in 14, 11 and 4 puppies that were 1, 2 and 3 months old, respectively while mRVNA titer was below protective level in 20, 16 and 12 puppies at 1, 2 and 3 months age, respectively.
RFFIT is a WHO recommended gold standard serological assay used for RVNA determination (Durrani et al.
RFFIT revealed a variation of mRVNA titers among different age groups of puppies (Table I).
The RFFIT was conducted by using Lab-Tek 8-well glass slides with covers (Nalge Nunc International, Naperville, IL).
Repeating the RFFIT assays with a challenge virus from phylogroup II, such as MOKV or LBV, could have tested this hypothesis further.