Table 8.
Rumen fermentation characteristics from feedlot animals fed high-grain diets supplemented with no additives (CON), monensin (MON, 33 mg/kg DM), 3-nitrooxypropanol (NOP, 125 mg/kg DM), and combination of MON and NOP
| −MON | +MON | P value | ||||||
|---|---|---|---|---|---|---|---|---|
| Variable | −NOP | +NOP | −NOP | +NOP | SEM | MON | NOP | MON × NOP |
| No. of steers | 8 | 8 | 8 | 8 | — | — | — | — |
| Total VFA, mM | 101.8 | 91.9 | 96.6 | 97.2 | 8.16 | 0.99 | 0.59 | 0.54 |
| Individual VFA, mol/100 mol | ||||||||
| Acetate (A) | 48.7 | 44.1 | 48.6 | 44.8 | 0.62 | 0.70 | <0.01 | 0.59 |
| Propionate (P) | 37.5 | 42.6 | 39.0 | 42.5 | 1.44 | 0.58 | <0.01 | 0.55 |
| Isobutyrate | 1.05 | 1.06 | 1.10 | 1.00 | 0.060 | 0.89 | 0.51 | 0.36 |
| Butyrate | 7.87 | 7.18 | 7.34 | 7.19 | 0.520 | 0.57 | 0.37 | 0.55 |
| Valerate | 2.87 | 3.19 | 2.18 | 2.88 | 0.290 | 0.09 | 0.09 | 0.47 |
| Isovalerate | 1.68 | 1.44 | 1.63 | 1.28 | 0.240 | 0.61 | 0.18 | 0.78 |
| Caproate | 0.38 | 0.39 | 0.27 | 0.31 | 0.030 | 0.04 | 0.43 | 0.63 |
| A:P ratio | 1.42 | 1.06 | 1.33 | 1.07 | 0.090 | 0.61 | 0.01 | 0.52 |
| NH3-N, mM | 4.26 | 2.30 | 2.99 | 2.60 | 0.670 | 0.49 | 0.15 | 0.29 |