Choline and choline esters are present in milk and are important for the suckling neonate. Choline concentrations in porcine milk had not been previously reported, therefore choline, glycerophosphocholine, phosphatidylcholine and phosphocholine concentrations in porcine prepartum mammary secretions, colostrum and milk were determined herein by HPLC and GC-MS. Milk samples were collected from second parity cross-bred sows by manual expression ~12 hr prepartum and on day 1 to 28 postpartum. The choline content of prepartum secretions was 5,121 ± 268 μmol/L. With the onset of lactation, the choline concentration initially declined to 2,235 ± 261 μmol/L, which was lower than prepartum secretions (P < 0.05). Between d 2 and 28 postpartum, the total choline concentration in porcine milk was relatively stable at 3,117 ± 498 μmol/L, however, the contribution of the individual choline compounds varied with lactation. Glycerophosphocholine predominated prepartum secretions 978.9 ± 1.7%) and on day 1 postpartum (42.9 ± 11.5%), whereas phosphocholine was the predominant choline moiety in milk after day 2 (55-78% of total choline). In general, the concentrations of choline and glycerophosphocholine declined, phosphocholine rose (from 24.3 ± 20.2% to 78.6 ± 4.7% of total choline) and phosphatidylcholine remained relatively constant (6.8 ± 1.0% of total choline) as lactation progressed. In summary, the total choline content of mature porcine milk averaged 3 mM. Assuming milk intake of 800 mL/day and an average body weight of 4 kg between days 1 and 28 postpartum, choline intake of the suckling piglet wold be ~600 μmoles/kg/day.
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism
- Molecular Biology
- Nutrition and Dietetics
- Clinical Biochemistry