More recently, emerging experimental evidence indicate Lf as an extremely conformationally dynamic protein that is prone to self-association. The macromolecule has a dumbbell shape, well described by a bi-axial ellipsoid with half-axis. While the levels of self-association were shown to Tilmicosin depend on the number of conditions such as Lf concentration, presence of salts, ligands, storage in solutions, iron saturation and temperature, a molecular level explanation remains yet to be understood for this phenomenon. Without salt or at physiological salt concentrations, bLf as well as hLf reportedly self-associate in aqueous solutions as dimers, trimers, and also as tetramers with tetramer being the dominant form. In these studies, gel filtration analysis also revealed small peaks of the decamer. For tetramer formation, which is the predominant molecular form of Lf in human serum, tears, and breast milk, UNC1215 calcium dependent oligomerization of hLf has been reported. Therefore the purification of bLf oligomer in our study is in agreement with the aforementioned findings of other investigators. Colostrum is known to contain higher concentrations of bLf and calcium ions than milk these could have also contributed to the self-association of bLf into HMW oligomeric complex along with the unidentified molecular trigger of self-association. HMW- bLf molecule was also found to be dissociated into the dimeric and monomeric forms of bLf when kept for 24 h in the presence of 1 M NaCl. This observation is inconsistent with earlier findings on hLf. As determined by gradient SDS-PAGE analysis followed by Western blotting with anti-bLf antibody, all the three bands were identified as bLf protein. More interestingly, a progressive increase in the intensity of monomeric,78 kDa band with a simultaneous decrease in the remaining HMW-bLf band was observed. This is clearly evident in Western blot. We have also noted that since the purified HMW-bLf sample was stored for about a year after purification and lyophilization, a much larger bLf aggregate in the stacking gel was identified that showed lower mobility protein material with a comparative decrease in its band density, than the $250 kDa oligomeric complex band observed just after the purification.