Identification of oligosaccharides in dog milk samples over time of lactation using 2 different chromatographic methods coupled with mass spectrometry and comparison of retention times with genuine pure standards.

m/z = mass to charge ratio of 2AB labelled oligosaccharide, tR(1) = retention time using method 1, tR(2) = retention time using method 2, Hex = hexose, HexNAc = N-acetylhexosamine, dHex = deoxyhexose, NeuAc = N-acetylneuraminic acid, NeuGc = N-glycolylneuraminic acid.* Identification based on mass data and comparison of tR with genuine standard, identification based on the fact that lactose-3-sulphate has previously been reported in dog milk by Bubb et.al. [21],¥two Hex3 oligosaccharides were separated by method one but only one peak is present when using method 2, so it is likely that they co-elute using method 2. nd = not detected/not determined.• = present.