Figure 2

Biofilm formation for the different conditions tested. Fourteen Mycobacterium avium subspecies hominissuis (seven from humans, six from swine, one from a bird), and three M. avium subsp.avium isolates from birds were used to optimise the method. Results are represented as mean OD⁵⁹⁵ value after crystal violet staining of biofilm + SEM (Standard error of the mean). Isolates forming biofilm (#1646, #1838, #1851, #VI101) are illustrated with black bars, and isolates not forming (#H1, #H3, #H5, #H12, #H15, #H28, #H38, #1591, #1831, #989, #1247, #ATTC25291, #R13) as grey bars. Abbreviations; w = week; 7H9 = Middlebrook 7H9 with OADC and Tween; 7H9 ÷ (OADC+Tween) = Middlebrook 7H9 with neither OADC nor Tween; 50:50 7H9:dH₂O = 50% Middlebrook 7H9 with OADC and Tween and 50% distilled water; Hanks' = Hanks' balanced salt solution and dH₂O = distilled water.