Table 2. Effects of dietary protein restriction on the pool size of plasma free AA 1 in growing pigs fasted for 12 h (μmol/L, n = 6).
| Diets 2 | SEM 1 | Sites | SEM | P value | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 18% CP 2 | 14% CP 2 | Carotid artery | Jejunal vein | Portal vein | Diet | Site | Diet × Site | |||||
| Essential AA | ||||||||||||
| Arginine | 148.5 | 93.2 | 5.2 | 103.6 | 139.6 | 119.3 | 6.4 | < 0.01 | 0.01 | 0.49 | ||
| Histidine | 100.7 | 54.3 | 3.9 | 72.7 | 79.4 | 80.5 | 4.7 | < 0.01 | 0.48 | 0.54 | ||
| Isoleucine | 163.4 | 73.8 | 7.8 | 106.6 | 131.6 | 117.6 | 9.5 | < 0.01 | 0.23 | 0.40 | ||
| Leucine | 312.7 | 190.6 | 14.0 | 231.4 | 267.1 | 256.5 | 17.2 | < 0.01 | 0.36 | 0.48 | ||
| Lysine | 192.8 | 184.1 | 11.9 | 177.9 | 194.8 | 192.7 | 14.6 | 0.61 | 0.68 | 0.58 | ||
| Methionine | 48.7 | 33.7 | 2.6 | 38.3 | 44.7 | 40.6 | 3.2 | < 0.01 | 0.39 | 0.87 | ||
| Phenylalanine | 135.9 | 84.7 | 5.4 | 100.5 | 116.7 | 113.6 | 6.7 | < 0.01 | 0.24 | 0.44 | ||
| Threonine | 205.0 | 186.6 | 23.8 | 181.8 | 212.4 | 193.3 | 29.1 | 0.60 | 0.76 | 0.78 | ||
| Valine | 289.6 | 176.0 | 8.0 | 218.9 | 248.5 | 230.9 | 9.8 | < 0.01 | 0.15 | 0.33 | ||
| Nonessential AA | ||||||||||||
| Alanine | 954.7 | 856.5 | 32.0 | 905.9 | 893.3 | 917.6 | 39.2 | 0.06 | 0.91 | 0.71 | ||
| Aspartate | 37.6 | 29.9 | 2.0 | 31.8 | 34.7 | 34.8 | 2.5 | 0.02 | 0.65 | 0.72 | ||
| Cysteine | 157.6 | 129.4 | 8.0 | 139.2 | 132.9 | 158.4 | 9.8 | 0.03 | 0.20 | 0.91 | ||
| Glutamate | 586.4 | 409.5 | 27.0 | 528.3 | 466.4 | 499.2 | 33.1 | < 0.01 | 0.45 | 0.64 | ||
| Glycine | 1484.8 | 1042.3 | 60.5 | 1217.1 | 1260.1 | 1313.5 | 74.1 | < 0.01 | 0.66 | 0.69 | ||
| Proline | 3022.3 | 2139.8 | 148.8 | 2807.6 | 2348.6 | 2586.9 | 182.3 | < 0.01 | 0.25 | 0.68 | ||
| Serine | 250.2 | 173.3 | 13.2 | 193.5 | 231.4 | 210.3 | 16.1 | < 0.01 | 0.30 | 0.52 | ||
| Tyrosine | 122.8 | 67.1 | 6.2 | 90.6 | 99.1 | 95.2 | 7.7 | < 0.01 | 0.74 | 0.78 | ||
| AA category | ||||||||||||
| Essential AA | 1877.8 | 1273.4 | 74.8 | 1461.4 | 1666.8 | 1598.6 | 91.6 | < 0.01 | 0.31 | 0.50 | ||
| Nonessential AA | 28661.6 | 16550.4 | 2797.8 | 20143.1 | 22756.2 | 24918.8 | 3426.6 | 0.01 | 0.63 | 0.74 | ||
| Branch chain AA | 765.7 | 440.3 | 29.7 | 556.9 | 647.3 | 605.0 | 36.4 | < 0.01 | 0.26 | 0.42 | ||
| Neutral AA | 29473.3 | 17052.8 | 2793.1 | 20690.2 | 23508.1 | 25590.9 | 3420.8 | 0.01 | 0.61 | 0.75 | ||
| Anionic AA | 624.0 | 439.4 | 28.1 | 560.1 | 501.1 | 534.0 | 34.5 | < 0.01 | 0.50 | 0.64 | ||
| Cationic AA | 442.1 | 331.6 | 14.9 | 354.2 | 413.8 | 392.5 | 18.3 | < 0.01 | 0.11 | 0.36 | ||
1 AA, amino acids; SEM, standard error of the mean.
2 18% CP and 14% CP represent experimental diets containing 18 and 14% crude protein respectively.