Table 5. Effect of the proportion of dietary wheat and pea starch on SCFA concentration (μmol/g of digesta) and composition (%) in the crop contents of broilers at 28 d of age.
| Diets | SEM | Regression | R2 | Equation | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 01 | 20 | 40 | 60 | 80 | 100 | |||||
| SCFA concentration (μmol/g) | ||||||||||
| Total | 54.5 | 56.9 | 58.0 | 60.6 | 61.7 | 63.5 | 0.99 | L = 0.008 | 0.41 | y = 0.09x + 54.8 |
| Acetic acid | 22.2 | 23.2 | 23.8 | 25.0 | 25.5 | 26.3 | 0.41 | L<0.001 | 0.52 | y = 0.04x + 22.3 |
| Propionic acid | 7.6 | 9.0 | 8.5 | 8.9 | 8.9 | 9.6 | 0.21 | L = 0.019 | 0.23 | y = 0.01x + 8.0 |
| Iso-butyric acid | 1.4 | 1.4 | 1.4 | 1.4 | 1.3 | 1.3 | 0.03 | NS | - | - |
| Butyric acid | - | - | - | - | - | - | - | - | - | - |
| Iso-valeric acid | - | - | - | - | - | - | - | - | - | - |
| Valeric acid | 1.4 | 1.4 | 1.4 | 1.2 | 1.2 | 1.1 | 0.06 | NS | - | - |
| Caproic acid | 0.6 | 0.6 | 0.5 | 0.6 | 0.6 | 0.5 | 0.02 | NS | - | - |
| Lactic acid | 21.4 | 21.5 | 22.3 | 23.6 | 24.2 | 24.7 | 0.56 | L = 0.019 | 0.23 | y = 0.04x + 21.07 |
| SCFA mixture composition (%) | ||||||||||
| Acetic acid | 40.8 | 40.8 | 41.1 | 43.9 | 41.4 | 41.5 | 0.51 | NS | - | - |
| Propionic acid | 13.9 | 15.8 | 14.8 | 15.6 | 14.4 | 15.2 | 0.37 | NS | - | - |
| Iso-butyric acid | 2.6 | 2.4 | 2.4 | 2.4 | 2.1 | 2.0 | 0.06 | L<0.001 | 0.41 | y = -0.005x + 2.6 |
| Butyric acid | - | - | - | - | - | - | - | - | - | - |
| Iso-valeric acid | - | - | - | - | - | - | - | - | - | - |
| Valeric acid | 2.5 | 2.4 | 2.5 | 2.1 | 2.0 | 1.7 | 0.11 | L = 0.006 | 0.30 | y = -0.008x + 2.6 |
| Caproic acid | 1.1 | 1.0 | 0.9 | 1.0 | 1.0 | 0.8 | 0.04 | NS | - | - |
| Lactic acid | 39.1 | 37.8 | 38.3 | 41.4 | 39.2 | 38.8 | 0.67 | 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; NS: not significant; number of replications = 12 male broilers.