Table 2.
Analyzed and calculated concentration of nitrogen, total and free amino acids in control (CON), optimal (OPT) and optimal + leucine (OPTLEU) diets1 (g/kg, as-fed basis)
| CON | OPT | OPTLEU | ||||
|---|---|---|---|---|---|---|
| Analyzed | Calculated2 | Analyzed | Calculated2 | Analyzed | Calculated2 | |
| Total | ||||||
| Dry matter | 887.6 | – | 889.5 | – | 891.5 | – |
| Nitrogen | 30.0 | 30.8 | 22.0 | 22.4 | 22.8 | 22.9 |
| Arginine | 12.3 | 12.6 | 7.5 | 7.8 | 8.0 | 7.8 |
| Histidine | 4.9 | 5.3 | 3.9 | 4.3 | 4.0 | 4.3 |
| Isoleucine | 8.5 | 8.1 | 6.1 | 6.0 | 6.4 | 6.0 |
| Leucine | 16.5 | 16.7 | 11.4 | 11.9 | 15.9 | 16.4 |
| Lysine | 11.1 | 10.4 | 10.8 | 10.1 | 11.1 | 10.1 |
| Methionine | 2.7 | 3.1 | 2.7 | 3.3 | 3.1 | 3.3 |
| Methionine + cysteine | 5.6 | 6.3 | 4.8 | 5.7 | 5.2 | 5.7 |
| Phenylalanine | 9.8 | 9.6 | 7.5 | 7.6 | 7.7 | 7.6 |
| Phenylalanine + tyrosine | 16.0 | 15.9 | 11.9 | 12.0 | 12.3 | 12.0 |
| Threonine | 7.2 | 7.3 | 6.4 | 6.8 | 6.6 | 6.8 |
| Tryptophan | 2.5 | 2.3 | 1.8 | 1.9 | 1.8 | 1.9 |
| Valine | 9.4 | 9.0 | 8.9 | 8.9 | 9.2 | 8.9 |
| Free amino acids | ||||||
| Arginine | 0.3 | – | 0.1 | – | 0.1 | – |
| Histidine | – | – | 0.7 | 0.7 | 0.7 | 0.7 |
| Isoleucine | 0.1 | – | 0.8 | 0.8 | 0.8 | 0.8 |
| Leucine | 0.1 | – | 0.1 | – | 4.3 | 4.5 |
| Lysine | 0.2 | – | 3.6 | 3.7 | 3.7 | 3.7 |
| Methionine3 | – | – | 0.7 | 1.1 | 0.7 | 1.1 |
| Methionine + cysteine | – | – | 0.7 | 1.1 | 0.7 | 1.1 |
| Phenylalanine | – | – | 1.2 | 1.3 | 1.2 | 1.3 |
| Phenylalanine + tyrosine | 0.1 | – | 1.2 | 1.3 | 1.2 | 1.3 |
| Threonine | 0.2 | – | 2.0 | 2.0 | 2.0 | 2.0 |
| Tryptophan4 | – | – | – | 0.5 | – | 0.5 |
| Valine | – | – | 2.7 | 2.9 | 2.7 | 2.9 |
1Analyzed values represents average across 3 blocks (feed mixes)
2Calculated values for the total amino acids are based on the amino acids concentration in feed ingredients according to NRC [13], and calculated values for the free amino acids correspond to the dietary inclusion rate in crystalline form
3Addition of DL-Methionine was omitted in one of the 3 blocks, thus reducing the overall free methionine concentration across all 3 blocks. The average free methionine concentration between blocks 1 and 3 was 0.11 and was zero in block 2. Therefore, across blocks 1, 2 and 3, average free Met was 0.07
4Analysis of free tryptophan was not performed