Table 7. The profile of free amino acids in the plasma of layers fed a diet with various metformin concentrations.
| Metformin (mg/kg) |
|||
|---|---|---|---|
| Amino acids (µmol/L) | 0 | 150 | 300 |
| Essential amino acids | |||
| Arginine | 84.0±6.9 | 109.7±8.7 | 100.4±6.8 |
| Histidine | 140.6±11.6 | 135.6±7.9 | 163.1±13.9 |
| Isoleucine | 118.5±6.9b | 151.0±8.2a | 159.2±10.9a |
| Leucine | 165.8±7.9b | 195.9±7.0a | 194.0±7.9a |
| Lysine | 293.7±23.2 | 286.0±14.1 | 313.1±15.7 |
| Methionine | 51.4±3.5 | 60.1±5.8 | 62.0±6.0 |
| Phenylalanine | 105.1±3.7 | 111.1±2.4 | 110.0±4.5 |
| Threonine | 340.6±21.6 | 314.3±5.8 | 336.1±10.2 |
| Tryptophan | 72.9±3.0 | 74.7±3.7 | 71.4±4.2 |
| Valine | 234.8±12.9 | 276.3±10.9 | 274.0±13.3 |
| Nonessential amino acids | |||
| Alanine | 370.4±20.3b | 467.8±18.7a | 440.8±17.5a |
| Asparagine | 498.0±40.1 | 666.3±49.3 | 673.2±68.6 |
| Aspartic acid | 25.5±2.8b | 27.1±4.6b | 46.0±6.2a |
| Cystine | 29.6±3.4 | 32.0±4.9 | 37.1±2.6 |
| Glutamine | 637.7±33.2 | 595.8±27.7 | 646.0±22.1 |
| Glutamic acid | 150.6±10.8b | 163.6±9.7b | 203.2±11.6a |
| Glycine | 392.4±24.2 | 405.5±20.0 | 414.3±21.2 |
| Proline | 405.7±42.3 | 477.1±32.7 | 534.7±35.2 |
| Serine | 498.8±42.4 | 507.4±18.5 | 462.1±19.5 |
| Tyrosine | 120.4±6.2 | 125.2±4.8 | 133.3±8.7 |
| α-Aminoadipic acid | 5.3±1.2b | 7.5±0.5ab | 10.9±1.3a |
| α-Aminobutyric acid | 7.4±2.6 | 6.2±0.8 | 8.5±2.9 |
| Amino ethanol | 7.0±0.5 | 7.0±0.4 | 8.3±0.4 |
| Anserine | 9.2±0.5b | 10.2±0.7ab | 12.6±1.1a |
| β-Alanine | 13.3±1.7 | 12.1±1.0 | 12.0±1.0 |
| Carnosine | 10.4±0.6b | 11.0±0.4ab | 12.7±0.5a |
| Citrulline | 6.9±0.7 | 11.5±2.2 | 11.6±2.1 |
| Cystathionine | 8.0±1.6 | 7.5±1.3 | 11.7±2.7 |
| Hydroxylysine | 2.7±0.7 | 3.5±0.6 | 3.6±0.6 |
| Hydroxyproline | 132.1±12.2b | 294.7±27.3a | 330.5±34.2a |
| Ornithine | 57.8±8.1 | 63.5±7.7 | 67.5±6.2 |
| Sarcosine | 1.7±0.3 | 1.6±0.2 | 1.7±0.3 |
| Nπ-Methylhistidine | 24.5±2.6 | 26.1±2.7 | 29.0±3.6 |
| Nτ-Methylhistidine | 9.8±1.2b | 15.2±1.2ab | 18.0±1.7a |
a, b
Means not sharinga common superscript letter in the same row were significantly different (Tukey's HSD test, P<0.05). Values are given as mean±SE. The number of chickens used in each treatment group was 8. ND; not detected.