Primary bovine thyroid (BTY) cells

When grown as monolayers in tube cultures and rolled after inoculation, BTY cells have been shown to be the most sensitive for detecting field strains of all seven serotypes of FMD virus (Snowdon, 1966; Donaldson et al., 1970; Ferris and Donaldson, 1984).

Cyropreserved ovine kidney cells

House and House, (1989) compared the sensitivity of cattle, mice, primary cell cultures, cryopreserved cell cultures and established cell lines for demonstrating FMD virus and found that infectivity titres obtained in freshly prepared BTY cells and by cattle intradermolingual inoculation were highest and statistically indistinguishable. Titres obtained by neonatal mouse inoculation were significantly lower than the titres obtained in thyroid cultures for serotypes A, C, Asia 1 and SAT 3. The cell cultures from cryopreserved newborn ovine kidney and embryonic ovine kidney were significantly less susceptible to serotype Asia1 than BTY cells but not significantly different when compared with the cattle assay for all serotypes. In terms of practicability and overall susceptibility cryopreserved ovine kidney cells are a good alternative when BTY cells are unavailable.

Primary pig kidney cells, primary calf kidney cells

These systems are also sensitive for detecting FMD virus strains, although less so (log10 0.5 - 1.0) than BTY cells.

BHK-21-CT cells

When maintained in a cell suspension plaque system, BHK-21-CT cells have been found to be more sensitive than BHK cells in other assay systems or neonatal mice, and can be used to detect the presence of FMD virus under certain circumstances.

Neonatal mice

Mice are an alternative to cell cultures. For maximum sensitivity the mice must be 2-7 days of age and of selected breed strains. Some field strains of virus may require several passages before they become adapted to mice.