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.