Table 2.
Chemical composition of experimental diet fed as a TMR (% of DM, unless noted).
| Composition | Treatments (SPR)1 | ||
|---|---|---|---|
| L-SPR (Control) | M-SPR | H-SPR | |
| NEL, Mcal / kg2 | 1.7 | 1.7 | 1.7 |
| CP | 15.6 | 15.6 | 15.7 |
| RDP3 | 9.3 | 9.3 | 9.3 |
| Starch | 26.4 | 26.5 | 26.7 |
| RDS3 | 19.4 | 21.1 | 22.9 |
| SPR | 2.1 | 2.3 | 2.5 |
| Ether extract | 4.5 | 4.6 | 4.8 |
| NDF | 31.6 | 31.7 | 31.7 |
| ADF | 17.5 | 17.6 | 17.7 |
| Forage NDF | 20.3 | 20.4 | 20.3 |
| peNDF8.04 | 15.2 | 15.2 | 15.3 |
| ERDST5 | 73.5 | 79.6 | 85.9 |
| ERDCP5 | 59.6 | 59.6 | 59.2 |
1SPR, dietary rumen-degradable starch to rumen-degradable protein ratio; L-SPR, low SPR; M-SPR, medium SPR; H-SPR, high SPR.2NEL, net energy for lactation, estimated by NRC (2001).3RDP (rumen degradable protein, %) = CP (%) × ERDCP (%); RDS (rumen degradable starch, %) = Starch (%) × ERDST (%).4peNDF8.0, physically effective NDF inclusive of particles > 8 mm, measured as the NDF content of diet multiplied by pef8.0.5ERDS, effective ruminal degradability for starch; ERDCP, effective ruminal degradability for protein.