Table 4. Species richness and diversity of rumen bacteria in Holstein and Jersey steers with different levels of mineral supplementation
Parameters | Holstein | Jersey | SEM | Mixed p-value |
CON | NM | HM | CON | NM | HM | B | T | B × T |
ASVs | 1,329.00 | 1,385.33 | 1,387.00 | 1,279.33 | 1,272.00 | 1,189.00 | 56.581 | 0.051 | 0.836 | 0.564 |
Chao1 | 1,332.60 | 1,392.55 | 1,391.04 | 1,284.44 | 1,275.88 | 1,190.71 | 57.306 | 0.052 | 0.823 | 0.562 |
Shannon | 8.91 | 9.05 | 9.17 | 8.74 | 8.86 | 8.67 | 0.105 | 0.019 | 0.605 | 0.395 |
Inverse Simpson | 0.995 | 0.995 | 0.996 | 0.992 | 0.993 | 0.992 | 0.001 | 0.023 | 0.781 | 0.737 |
Good’s coverage | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 0.000 | 0.846 | 0.533 | 0.741 |
Con, only TMR (without mineral supplementation); NM, TMR + NRC recommended concentration of mineral supplementation (Se 0.1 ppm + Zn 30 ppm + Cu 10 ppm)/kg DM; HM, TMR + higher than recommended concentration of mineral supplementation (Se 3.5 ppm + Zn 350 ppm + Cu 28 ppm)/kg DM; B, breed effect; T, trace mineral supplementation effect; B × T, interaction effect between breed and trace mineral supplementation.
ASV, amplicon sequence variant; TMR, total mixed rations; NRC, National Research Council; DM, dry matter.