Perinatal Dietary Choline Deficiency in Sows Influences Concentrations of Choline Metabolites, Fatty Acids, and Amino Acids in Milk throughout Lactation.

BACKGROUND: Choline is essential for synthesis of phospholipids, neurodevelopment, and DNA methylation. It is unknown whether dietary perinatal choline deficiency affects maternal milk composition. OBJECTIVE: We examined whether perinatal maternal dietary choline deficiency influences porcine-milk composition. METHODS: Yorkshire sows were fed choline-deficient (CD) or choline-sufficient (CS) gestation diets [544 or 1887 mg choline/kg dry matter (DM), respectively] from 65 d before to 48 h after parturition and then fed lactation diets (517 or 1591 mg choline/kg DM, respectively) through day 19 of lactation. Milk was collected from 7 sows fed each diet at days 0 (colostrum), 7-9 (mature milk), and 17-19 (preweaning) of lactation. Sow plasma was collected 65 d before and 19 d after parturition. Milk was analyzed for choline metabolite, fatty acid (FA), and amino acid composition. All outcomes were analyzed to assess main and interactive effects of choline intake and time. RESULTS: Plasma choline metabolites did not differ before treatment, but free choline, betaine, and dimethylglycine concentrations were lower in CD-fed than in CS-fed sows at day 19 of lactation (interaction; P < 0.05). Milk betaine concentrations responded similarly, with no differences due to choline intake at day 0 of lactation, but lower concentrations in CD-fed than in CS-fed sows at day 18 of lactation (interaction; P < 0.001). Certain milk long-chain FAs also exhibited no differences at day 0 of lactation but higher concentrations in CD-fed than in CS-fed sows at day 18 of lactation (P < 0.05). CONCLUSIONS: These data indicate that, in pigs, dietary choline deficiency induces alterations in plasma choline metabolites that are evident at the end of lactation. Betaine and select FAs in milk are sensitive to maternal dietary choline deficiency and day of lactation. Alterations in concentrations of these nutrients may affect early-life neonatal development.

Porcine Milk Oligosaccharides and Sialic Acid Concentrations Vary Throughout Lactation.

BACKGROUND: Milk oligosaccharides (OSs) are bioactive components known to influence neonatal development. These compounds have specific physiological functions acting as prebiotics, immune system modulators, and enhancing intestine and brain development. OBJECTIVES: The pig is a commonly used model for studying human nutrition, and there is interest in quantifying OS composition of porcine milk across lactation compared with human milk. In this study, we hypothesized that OS and sialic acid (SA) composition of porcine milk would be influenced by stage of lactation. METHODS: Up to 250 mL of milk were collected from seven sows at each of three time points: day 0 (colostrum), days 7-9 (mature), and days 17-19 (weaning). Colostrum was collected within 6 h of farrowing and 3-day intervals were used for mature and weaning milk to ensure representative sampling. Milk samples were analyzed for OS profiles by Nano-LC Chip-QTOF MS, OS concentrations via HPAEC-PAD, and SA (total and free) was assessed by enzymatic reaction fluorescence detection. RESULTS: Sixty unique OSs were identified in porcine milk. Neutral OSs were the most abundant at each lactation stage (69-81%), followed by acidic-sialylated OSs (16-29%) and neutral-fucosylated OSs (2-4%). As lactation progressed, acidic OSs decreased (P = 0.003), whereas neutral-fucosylated (P < 0.001) and neutral OSs (P = 0.003) increased throughout lactation. Six OSs were present in all samples analyzed across lactation [lacto-N-difucohexaose I (LNDFH-I), 2'-fucosyllactose (2'-FL), lacto-N-fucopentaose I (LNFP-I), lacto-N-neohexaose (LNnH), α1-3,ß-4-d-galactotriose (3-Hex), 3'-sialyllactose (3'-SL)], while LDFT was present only in colostrum samples. Analysis of individual OS concentrations indicated differences (P = 0.023) between days 0 and 7. Conversely, between days 7 and 18, OS concentrations remained stable with only LNnH (P < 0.001) and LNDFH-I (P = 0.002) decreasing over this period. Analysis of free SA indicated a decrease (P < 0.001) as lactation progressed, while bound (P < 0.001) and total (P < 0.001) SA increased across lactation. CONCLUSION: Concentrations of OS differ between colostrum and mature milk in the pig, and SA concentrations shift from free to bound forms as lactation progresses. Our results suggest that although porcine milk OS concentration and the number of structures is lower than human milk, the OS profile appears to be closer to human milk rather than to bovine milk, based on previously published profiles.