Neutral and acidic oligosaccharides in Holstein-Friesian colostrum during the first 3 days of lactation measured by high performance liquid chromatography on a microfluidic chip and time-of-flight mass spectrometry

Abstract

Oligosaccharides (OS) from bovine milk are a class of bioactive molecules that are receiving increasing commercial attention for their potential health benefits. In the present work we measured, comprehensively and systematically, free milk OS in the colostrum of 7 Holstein-Friesian cows during the first 3 d of lactation in 12-h intervals by HPLC-chip/time-of-flight mass spectrometry to determine the biological variation of free milk OS in early lactation. The high sensitivity and resolution of the analytical technique made it possible to monitor all OS species, thus providing a comprehensive and quantitative analysis of OS variations during colostrum production. This study confirmed that although sialyllactose is the major OS in bovine colostrum, several neutral OS species are present in significant abundance even at the third day of lactation. Furthermore, variation in terms of OS species and relative abundances of OS between cows suggest individual animal variation. These variations are likely due to genetic factors because environmental factors such as nutrition, lactation number, and accommodation were the same for all cows. This investigation revealed that colostrum milk from Holstein-Friesian cows is a rich source of neutral and acidic OS for the food and pharmaceutical industries.

Figure 1

Distribution of oligosaccharides in colostrum samples collected during the first 60 h of colostrum production from 6 individual Holstein-Friesian cows.

Figure 2

Distribution of acidic and neutral oligosaccharides (OS) in individual cows during the first 60 h of colostrum production.

Figure 3

Extracted-ion chromatogram of ion m/z 636.23. Two sialyllactose (SL) isomers eluted at 8.0 min (α2–6 SL) and 21.0 min (α2–3 SL), respectively.

Figure 4

Area under the curve (AUC) distribution of 3′-sialyllactose (α2–3 SL) in individual cows during the first 60 h of colostrum production.

Figure 5

Area under the curve (AUC) distribution of 6′-sialyllactose (α2–6 SL) in individual cows during the first 60 h of colostrum production.

Figure 6

Distribution of 2 neutral N-acetylhexosamine (HexNAc)-containing oligosaccharides from individual cows during the first 60 h of colostrum production. The sample from cow #2611 at 48 h was excluded from the study because of the presence of contaminants.