Table 2.
Total amino acid content (mg/100 g) of milk from the different lactation periods.
| Lactation Period | |||||
|---|---|---|---|---|---|
| 5–11 Days | 12–30 Days | 1–2 Months | 2–4 Months | 4–8 Months | |
| IAA † | |||||
| Histidine | 51.2 (19.9) | 44.5 § (14.1) | 36.5 § (12.6) | 34.9 § (7.2) | 25.0 § (6.8) |
| Isoleucine | 81.0 (23.4) | 71.6 § (15.4) | 64.6 § (16.8) | 54.0 § (11.6) | 53.8 (10.7) |
| Leucine | 153.7 (63.2) | 133.7 § (35.1) | 130.3 (33.5) | 108.1 § (24.9) | 122.6 § (38.8) |
| Lysine | 112.0 (31.0) | 93.8 § (23.1) | 78.8 § (18.9) | 63.4 § (13.1) | 67.9 § (13.1) |
| Methionine | 21.8 (11.7) | 16.7 § (6.6) | 13.0 § (9.0) | 9.2 § (6.1) | 11.8 § (7.1) |
| Phenylalanine | 64.4 (35.9) | 52.4 § (18.3) | 40.4 § (13.6) | 37.6 § (10.8) | 28.4 § (9.0) |
| Threonine | 85.1 (28.1) | 66.9 § (14.6) | 58.0 § (13.3) | 50.0 § (8.7) | 48.6 (11.3) |
| Valine | 97.9 (34.3) | 81.1 § (16.7) | 72.1 § (21.0) | 59.7 § (16.0) | 60.9 (12.7) |
| DAA † | |||||
| Alanine | 70.9 (23.0) | 55.9 § (14.3) | 45.9 § (15.7) | 38.7 § (10.9) | 38.6 (9.1) |
| Arginine | 106.5 (36.6) | 90.8 § (22.8) | 77.0 § (24.5) | 64.6 § (21.3) | 65.3 (16.7) |
| Asx ‡ | 132.9 (84.1) | 115.5 § (54.4) | 106.9 (40.0) | 97.2 (56.8) | 83.8 § (24.6) |
| Cystine | 25.4 (12.5) | 17.7 § (6.3) | 12.5 § (5.2) | 12.3 (3.4) | 9.9 § (5.5) |
| Glx ‡ | 248.1 (193.7) | 220.1 § (92.4) | 216.3 (59.3) | 188.6 (105.2) | 182.8 § (30.8) |
| Glycine | 46.3 (15.2) | 34.5 § (9.7) | 27.6 § (10.5) | 23.6 § (7.0) | 23.5 (6.8) |
| Proline | 140.2 (42.4) | 117.7 § (26.5) | 110.6 § (25.4) | 95.3 § (20.9) | 94.5 (17.2) |
| Serine | 77.8 (27.0) | 59.0 § (14.1) | 47.9 § (9.8) | 42.9 § (8.1) | 41.7 (8.0) |
| Tyrosine | 72.5 (30.4) | 57.7 § (14.1) | 44.1 § (19.5) | 41.4 (13.9) | 37.1 § (10.3) |
| SUM | 1608.3 (589.5) | 1296.5 § (368.4) | 1188.1 § (341.7) | 1053.2 § (291.9) | 992.4 (175.9) |
† IAA = indispensable amino acids; DAA = dispensable amino acid; ‡ Asx = sum of aspartic acid + asparagine; Glx = sum of glutamic acid + glutamine. Medians (inter-quartile ranges) of n = 90 samples per lactation period are shown. A median with a “§” superscript is significantly different from the median of the previous lactation period (p < 0.05).