Item | Supplemental methionine level (% of dietary DM) | ||||
---|---|---|---|---|---|
|
|||||
0 | 0.032 | 0.064 | 0.096 | 0.128 | |
Ingredient composition (%, DM basis) | |||||
Steam-flaked corn | 74.95 | 73.91 | 73.88 | 73.84 | 73.81 |
Sudan grass hay | 7.68 | 7.68 | 7.68 | 7.68 | 7.68 |
Alfalfa hay | 3.84 | 3.84 | 3.84 | 3.84 | 3.84 |
Tallow | 3.09 | 3.09 | 3.09 | 3.09 | 3.09 |
Molasses | 7.37 | 7.37 | 7.37 | 7.37 | 7.37 |
Magnesium oxide | 0.18 | 0.18 | 0.18 | 0.18 | 0.18 |
Dicalcium phosphate | 0.49 | 0.49 | 0.49 | 0.49 | 0.49 |
Limestone | 1.22 | 1.22 | 1.22 | 1.22 | 1.22 |
Urea | 0.88 | 0.88 | 0.88 | 0.88 | 0.88 |
Trace mineral salt2) | 0.30 | 0.30 | 0.30 | 0.30 | 0.30 |
Smartamine3) (%) | 0 | 0.032 | 0.064 | 0.096 | 0.128 |
Aminoshure4) (%) | 0 | 1.01 | 1.01 | 1.01 | 1.01 |
Nutrient composition (DM basis)5) | |||||
Net energy (Mcal/kg) | |||||
Maintenance | 2.21 | 2.21 | 2.21 | 2.21 | 2.21 |
Gain | 1.55 | 1.55 | 1.55 | 1.55 | 1.55 |
Crude protein (%) | 11.5 | 12.2 | 12.2 | 12.3 | 12.3 |
Ether extract (%) | 6.51 | 6.51 | 6.51 | 6.51 | 6.51 |
NDF (%) | 13.25 | 13.25 | 13.25 | 13.25 | 13.25 |
Calcium (%) | 0.73 | 0.73 | 0.73 | 0.73 | 0.73 |
Phosphorus (%) | 0.36 | 0.36 | 0.36 | 0.36 | 0.36 |
Potassium (%) | 0.79 | 0.79 | 0.79 | 0.79 | 0.79 |
Magnesium (%) | 0.28 | 0.28 | 0.28 | 0.28 | 0.28 |
Sulfur (%) | 0.16 | 0.1 | 0.16 | 0.16 | 0.16 |
2) Trace mineral salt contained: CoSO4, 0.068%; CuSO4, 1.04%; FeSO4, 3.57%; ZnO, 1.24%; MnSO4, 1.07%, KI 0.052%, and NaCl, 92.96%.
3) Supplemental Smartamine (as % of dietary DM): Treatment 1 = 0%; treatment 2 = 0.032%; treatment 3= 0.064%; treatment 4 = 0.096%, and treatment 5 = 0.128%).
5) Calculated based on tabular values expressed for individual feed ingredients (NRC [3]).
Item | Supplemental methionine (% of dietary DM) | SEM | Contrast p-value | |||||
---|---|---|---|---|---|---|---|---|
|
|
|||||||
0 | 0.032 | 0.064 | 0.096 | 0.128 | Linear | Quadratic | ||
Intake (g/d) | ||||||||
DM | 4,160 | 4,202 | 4,204 | 4,205 | 4,206 | 28 | 0.16 | 0.88 |
OM | 3,928 | 3,970 | 3,972 | 3,973 | 3,974 | 26 | 0.16 | 0.88 |
N | 67.6 | 67.7 | 67.8 | 67.9 | 68.0 | 0.44 | 0.16 | 0.88 |
Leaving abomasum (g/d) | ||||||||
OM | 1,949 | 1,793 | 1,880 | 1,806 | 1,897 | 41.0 | 0.50 | 0.05 |
N | 80.6 | 79.22 | 81.5 | 83.9 | 81.6 | 1.7 | 0.22 | 0.79 |
Non-ammonia N | 77.2 | 75.9 | 78.2 | 80.44 | 77.9 | 1.7 | 0.28 | 0.69 |
Microbial N | 44.5 | 47.1 | 49.4 | 45.6 | 49.2 | 2.2 | 0.27 | 0.64 |
Feed N | 22.9 | 19.0 | 18.9 | 24.9 | 18.8 | 2.1 | 0.75 | 0.85 |
Ruminal digestion (%) | ||||||||
OM | 61.7 | 66.7 | 65.1 | 66.0 | 64.6 | 1.1 | 0.16 | 0.03 |
Feed N | 66.2 | 72.0 | 72.1 | 63.2 | 72.2 | 3.1 | 0.72 | 0.85 |
Microbial N efficiency1) | 18.4 | 17.9 | 19.1 | 17.4 | 19.2 | 0.8 | 0.66 | 0.59 |
N efficiency2) | 1.14 | 1.12 | 1.15 | 1.18 | 1.15 | 0.02 | 0.38 | 0.69 |
Postruminal digestion (%) | ||||||||
OM | 55.7 | 55.0 | 59.5 | 57.4 | 58.1 | 1.8 | 0.24 | 0.57 |
N | 70.7 | 70.5 | 74.0 | 75.2 | 72.7 | 1.2 | 0.04 | 0.15 |
Fecal excretion (g/d) | ||||||||
DM | 976 | 921 | 866 | 872 | 909 | 37.4 | 0.15 | 0.11 |
OM | 861 | 803 | 760 | 769 | 795 | 35.4 | 0.17 | 0.12 |
N | 23.6 | 23.3 | 21.1 | 20.9 | 22.1 | 0.9 | 0.09 | 0.16 |
Total-tract digestión (%) | ||||||||
DM | 76.5 | 78.1 | 79.4 | 79.3 | 78.4 | 0.89 | 0.11 | 0.08 |
OM | 78.1 | 79.8 | 80.9 | 80.6 | 80.0 | 0.89 | 0.12 | 0.09 |
N | 65.0 | 65.5 | 68.8 | 69.3 | 67.4 | 1.3 | 0.07 | 0.16 |
DE (%) | 75.7 | 76.7 | 78.1 | 78.0 | 76.7 | 0.96 | 0.32 | 0.12 |
DE diet (Mcal/kg) | 3.34 | 3.35 | 3.41 | 3.40 | 3.34 | 0.04 | 0.65 | 0.22 |
Item | Supplemental methionine level (% of dietary DM) | SEM | Contrast p-value | |||||
---|---|---|---|---|---|---|---|---|
|
|
|||||||
0 | 0.032 | 0.064 | 0.096 | 0.128 | Linear | Quadratic | ||
Methionine | ||||||||
NRC [3] level 1 | 8.02 | 8.62 | 9.22 | 9.82 | 10.42 | |||
Leaving abomasum | 7.63 | 7.95 | 8.35 | 8.62 | 8.33 | 0.2 | 0.01 | 0.12 |
Lysine | ||||||||
NRC [3] level 1 | 21.9 | 30.0 | 30.0 | 30.0 | 30.0 | |||
Leaving abomasum | 26.4 | 27.5 | 28.3 | 27.6 | 27.3 | 0.6 | 0.28 | 0.06 |
Histidine | ||||||||
NRC [3] level 1 | 9.5 | 9.4 | 9.4 | 9.4 | 9.4 | |||
Leaving abomasum | 9.1 | 8.9 | 8.9 | 9.4 | 9.2 | 0.3 | 0.56 | 0.72 |
Phenylalanine | ||||||||
NRC [3] level 1 | 21.6 | 21.3 | 21.3 | 21.3 | 21.3 | |||
Leaving abomasum | 18.7 | 18.7 | 19.0 | 19.3 | 19.1 | 0.5 | 0.47 | 0.90 |
Threonine | ||||||||
NRC [3] level 1 | 22.0 | 21.8 | 21.8 | 21.8 | 21.8 | |||
Leaving abomasum | 18.9 | 18.8 | 19.4 | 19.9 | 19.6 | 0.7 | 0.23 | 0.84 |
Leucine | ||||||||
NRC [3] level 1 | 42.8 | 42.0 | 42.0 | 42.0 | 42.0 | |||
Leaving abomasum | 34.5 | 34.4 | 34.7 | 35.7 | 35.7 | 1.2 | 0.34 | 0.85 |
Isoleucine | ||||||||
NRC [3] level 1 | 21.6 | 21.3 | 21.3 | 21.3 | 21.3 | |||
Leaving abomasum | 18.3 | 18.3 | 18.8 | 19.1 | 18.8 | 0.6 | 0.40 | 0.69 |
Valine | ||||||||
NRC [3] level 1 | 24.9 | 24.7 | 24.7 | 24.7 | 24.7 | |||
Leaving abomasum | 20.0 | 19.8 | 20.1 | 21.3 | 20.7 | 0.7 | 0.23 | 0.97 |
Arginine | ||||||||
NRC [3] level 1 | 19.2 | 19.1 | 19.1 | 19.1 | 19.1 | |||
Leaving abomasum | 17.2 | 17.1 | 17.0 | 18.1 | 17.2 | 0.7 | 0.62 | 0.89 |
Item | Supplemental methionine level (% of dietary DM) | Requirement (NRC [3]) | ||||
---|---|---|---|---|---|---|
|
||||||
0 | 0.032 | 0.064 | 0.096 | 0.128 | ||
Metabolizable amino acid (g/d) | ||||||
Period 1–56 d | ||||||
Methionine | 6.6 | 6.8 | 7.0 | 7.1 | 7.1 | 9.0 |
Lysine | 22.8 | 23.7 | 23.6 | 22.7 | 23.2 | 28.7 |
Arginine | 14.9 | 14.7 | 14.2 | 14.9 | 14.6 | 14.8 |
Threonine | 16.4 | 16.2 | 16.2 | 16.4 | 16.6 | 17.5 |
Leucine | 29.9 | 29.6 | 29.0 | 29.4 | 30.3 | 30.1 |
Isoleucine | 15.8 | 15.7 | 15.7 | 15.7 | 15.9 | 12.6 |
Valine | 17.3 | 17.0 | 16.8 | 17.5 | 17.6 | 17.9 |
Histidine | 7.9 | 7.7 | 7.4 | 7.7 | 7.8 | 11.2 |
Phenylalanine | 16.2 | 16.1 | 15.9 | 15.9 | 16.2 | 15.7 |
Period 56–112 d | ||||||
Methionine | 8.2 | 8.0 | 7.9 | 7.9 | 7.9 | 10.4 |
Lysine | 28.2 | 27.8 | 27.2 | 27.4 | 27.4 | 33.2 |
Arginine | 18.4 | 18.1 | 17.7 | 17.9 | 17.9 | 17.1 |
Threonine | 20.2 | 19.9 | 19.4 | 19.6 | 19.6 | 20.2 |
Leucine | 36.9 | 36.4 | 35.5 | 35.8 | 35.8 | 34.7 |
Isoleucine | 19.6 | 19.3 | 18.8 | 19.0 | 19.0 | 14.5 |
Valine | 21.4 | 21.1 | 20.6 | 20.8 | 20.8 | 20.7 |
Histidine | 9.7 | 9.6 | 9.4 | 9.5 | 9.5 | 13.0 |
Phenylalanine | 20.0 | 19.7 | 19.2 | 19.4 | 19.4 | 18.1 |
Period 1–112 d | ||||||
Methionine | 7.4 | 7.4 | 7.4 | 7.5 | 7.5 | 9.6 |
Lysine | 25.5 | 25.7 | 25.4 | 25.1 | 25.3 | 30.8 |
Arginine | 16.6 | 16.4 | 15.9 | 16.4 | 16.2 | 15.9 |
Threonine | 18.3 | 17.9 | 18.0 | 18.4 | 18.4 | 18.8 |
Leucine | 33.4 | 32.7 | 32.2 | 33.1 | 33.5 | 32.2 |
Isoleucine | 17.7 | 17.4 | 17.4 | 17.4 | 17.7 | 13.5 |
Valine | 19.3 | 19.1 | 18.7 | 19.2 | 19.2 | 19.2 |
Histidine | 8.8 | 8.6 | 8.4 | 8.6 | 8.6 | 12.0 |
Phenylalanine | 18.1 | 17.8 | 17.6 | 17.9 | 17.9 | 16.8 |
1) Diets formulated to meet average metabolizable protein requirements. Supply of metabolizable amino acids were estimated using NRC [3] Level 1 approach, based on tabular compositional values [3] for individual feed ingredients (Table 1), and observed dry matter intake and live weight (Table 2). Metabolizable amino acid requirements were estimated based on observed average live weight and weight gain for cattle on the three-phase feeding program (Table 2) [3,4].