Table 4.
Effect of different inclusion levels of SRU on absolute and relative quantities of rumen microbes in a Rusitec fed a finishing beef diet‡
| P value | ||||||||
|---|---|---|---|---|---|---|---|---|
| Inclusion levels of SRU, % | Treatment | Contrasts | ||||||
| Item | 0 | 0.5 | 1 | 1.75 | SEM | Linear | Quadratic | |
| Absolute quantities* | ||||||||
| Total Bacteria 16S rRNA copies, ×107 | 7.84 | 5.74 | 8.76 | 4.88 | 1.430 | 0.36 | 0.506 | 0.674 |
| Methanogens, mcrA copies, ×104 | 1.58 | 1.05 | 3.47 | 2.24 | 0.921 | 0.41 | 0.410 | 0.792 |
| Fibrobacter succinogenes, 16S rRNA copies, ×105 | 1.49 | 0.30 | 1.20 | 0.91 | 0.210 | 0.69 | 0.988 | 0.512 |
| Selenomonas ruminantium, 16S rRNA copies, ×105 | 5.12 | 2.95 | 7.26 | 3.39 | 1.140 | 0.45 | 0.778 | 0.669 |
| Relative quantities† | ||||||||
| Methanogens, ×10−4% | 20.1 | 19.0 | 32.5 | 46.7 | 9.21 | 0.52 | 0.213 | 0.833 |
| Fibrobacter succinogenes, % | 0.19 | 0.05 | 0.14 | 0.19 | 0.034 | 0.75 | 0.691 | 0.325 |
| Selenomonas ruminantium, % | 0.25 | 0.11 | 0.55 | 0.31 | 0.095 | 0.53 | 0.519 | 0.941 |
*Absolute quantities are the average quantities of the target before normalization based on 16S rRNA total bacteria target.
†Relative quantities of the target are the average populations calculated as a percentage of the total bacterial 16S rRNA.
‡All the acronyms are defined in the text.