Abstract: In this study, gas chromatography (GC) and ultra-high performance liquid chromatography-quadrupole-time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS) were used to explore the effects of feeding Schizochytrium spp. on the fatty acid and lipid composition of goat milk, and the differences in fatty acid and lipid composition between goat milk and commercially available pure bovine milk and docosahexaenoic acid (DHA)-enriched bovine milk were analyzed. The results showed that the lipid content was significantly higher in goat milk than in bovine milk (P < 0.05), the major fatty acids in both goat and bovine milk were myristic acid, palmitic acid and oleic acid. The content of DHA in goat milk was significantly increased by feeding Schizochytrium spp.. Triglycerides were the major lipid components in goat and bovine milk, and the phospholipid content in goat milk was significantly higher than that in bovine milk. DHA was mainly present in an glyceride esterified form in dairy milk lipids, and goat milk contained more phospholipid (PL)-bound DHA than bovine milk. Feeding Schizochytrium spp. at 50 g/day provided the highest DHA enrichment in goat milk. In a nutshell, this study demonstrated that dietary DHA supplementation can improve the nutritional value of goat milk, thereby solving the problem of the single source of dietary DHA.

Key words: goat milk; docosahexaenoic acid; Schizochytrium spp.; lipidomics