Studies on the carbohydrate content of milk of the crabeater seal (Lobodon carcinophagus).

1. The mean carbohydrate content of six samples of milk of the crabeater seal (a phocid), measured as total hexose, was 1.5 +/- 0.3% (w/v). Ultrafiltrates of the skim milk of these samples had a mean carbohydrate content of 1.9 +/- 0.2%. 2. Thin-layer chromatography of the ultrafiltrates showed that this carbohydrate consists mainly of various oligosaccharides of low chromatographic mobility; lactose and traces of free glucose and galactose were also detected. 3. These oligosaccharides consisted mainly of D-galactose and N-acetylhexosamine; L-fucose, D-glucose and sialic acid were additional minor components. 4. The mean lactose content of the ultrafiltrates, determined by a specific enzymic method, was 0.021 +/- 0.007% (w/v); this is similar to the levels which have been reported for the milk of otariids.