Table 6. Effect of the proportion of dietary wheat and pea starch on SCFA concentration (μmol/g of digesta) and composition (%) in the ileal contents of broilers at 28 d of age.
| Diets | SEM | Regression | R2 | Equation | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 01 | 20 | 40 | 60 | 80 | 100 | |||||
| SCFA concentration (μmol/g) | ||||||||||
| Total | 67.2 | 78.8 | 84.2 | 96.7 | 93.4 | 74.7 | 3.82 | Q = 0.025 | 0.27 | y = -0.008x2 + 1.0x + 64.7 |
| Acetic acid | 60.2 | 60.7 | 63.5 | 61.3 | 63.8 | 59.1 | 1.11 | NS | - | - |
| Propionic acid | 4.7 | 6.3 | 8.4 | 9.9 | 9.4 | 8.1 | 0.70 | L = 0.050 | 0.17 | y = 0.04x + 5.8 |
| Iso-butyric acid | 0.5 | 0.6 | 0.9 | 0.4 | 1.2 | 1.0 | 0.13 | NS | - | - |
| Butyric acid | - | 1.7 | 1.5 | 1.0 | 2.2 | 1.4 | 0.29 | NS | - | - |
| Iso-valeric acid | 0.5 | 0.8 | 1.0 | 0.6 | 1.1 | 0.7 | 0.12 | NS | - | - |
| Valeric acid | 0.4 | 0.5 | 0.6 | 0.4 | 1.0 | 0.9 | 0.14 | NS | - | - |
| Caproic acid | 1.1 | 0.8 | 1.1 | 1.0 | 1.1 | 0.8 | 0.10 | NS | - | - |
| Lactic acid | - | 7.4 | 7.3 | 22.1 | 13.6 | 2.6 | 3.45 | NS | - | - |
| SCFA mixture composition (%) | ||||||||||
| Acetic acid | 90.0 | 78.6 | 77.3 | 67.0 | 72.6 | 79.2 | 3.10 | NS | - | - |
| Propionic acid | 6.6 | 7.8 | 10.2 | 10.9 | 10.4 | 10.7 | 0.87 | NS | - | - |
| Iso-butyric acid | 0.7 | 0.6 | 1.0 | 0.4 | 1.3 | 1.4 | 0.14 | NS | - | - |
| Butyric acid | - | 2.0 | 1.6 | 0.8 | 2.3 | 2.0 | 0.29 | NS | - | - |
| Iso-valeric acid | 0.7 | 1.0 | 1.2 | 0.7 | 1.2 | 0.9 | 0.14 | NS | - | - |
| Valeric acid | 0.5 | 0.6 | 0.6 | 0.3 | 1.0 | 1.1 | 0.15 | NS | - | - |
| Caproic acid | 1.6 | 1.1 | 1.3 | 1.0 | 1.2 | 1.1 | 0.12 | NS | - | - |
| Lactic acid | - | 8.4 | 6.8 | 19.0 | 10.1 | 3.7 | 2.87 | NS | - | - |
1 Diets denominations indicate the percentage of pea starch in the starch fraction of the diet.
SEM: pooled standard error of the mean; L: linear regression P value; Q: quadratic regression P value; NS: not significant; number of replications = 12 male broilers.