Dry (Far off) | Close (Close up) | Cow - Fresh | Cow - Early | Cow - Mid | Cow - Late | 6-mo Heifer | 12-mo Heifer | 18-mo Heifer | 24-mo Heifer (Close up) | |
---|---|---|---|---|---|---|---|---|---|---|
Body wt (kg) | 675 | 675 | 675 | 675 | 675 | 675 | 200 | 300 | 450 | 625 |
DMI (kg/day) | 14 | 10 | 15 | 30 | 24 | 20 | 5 | 7 | 11 | 10 |
Milk productiona (kg/day) | 35 | 55 | 35 | 25 | ||||||
Crude protein (%)b | 9.9 | 12.4 | 19.5 | 16.7 | 15.2 | 14.1 | 12.3 | 11.4 | 8.8 | 15.0 |
RDP (%) | 7.7 | 9.6 | 10.5 | 9.8 | 9.7 | 9.5 | 9.4 | 9.5 | 8.8 | 10.1 |
RUP (%) | 2.2 | 2.8 | 9.0 | 6.9 | 5.5 | 4.6 | 2.9 | 1.9 | 0.004 | 4.9 |
MP (%) | 6.0 | 8.0 | 13.8 | 11.6 | 10.2 | 9.2 | 7.2 | 7.0 | 5.3 | 9.7 |
NEL (Mcal/kg) | 1.32 | 1.43 | 1.8c | 1.61 | 1.47 | 1.36 | — | — | — | 1.58 |
ME (Mcal/kg) | 2.05 | 2.27 | 1.80 | |||||||
NDF (%) | 40 | 35 | 30 | 28 | 30 | 32 | 30 | 32 | 33 | 35 |
ADF (%) | 30 | 25 | 21 | 19 | 21 | 24 | 20 | 22 | 24 | 25 |
NFC (%) | 30 | 34 | 35 | 38 | 35 | 32 | 35 | 30 | 25 | 34 |
Calcium (%) | 0.44 | 0.48 | 0.79 | 0.60 | 0.61 | 0.62 | 0.41 | 0.41 | 0.37 | 0.40 |
Phosphorus (%) | 0.22 | 0.26 | 0.42 | 0.38 | 0.35 | 0.32 | 0.28 | 0.23 | 0.18 | 0.23 |
Magnesium (%) | 0.11 | 0.40 | 0.29 | 0.21 | 0.19 | 0.18 | 0.11 | 0.11 | 0.08 | 0.40 |
Chlorine (%) | 0.13 | 0.20 | 0.20 | 0.29 | 0.26 | 0.24 | 0.11 | 0.12 | 0.10 | 0.20 |
Sodium (%) | 0.10 | 0.14 | 0.34 | 0.22 | 0.23 | 0.22 | 0.08 | 0.08 | 0.07 | 0.14 |
Potassium (%) | 0.51 | 0.62 | 1.24 | 1.07 | 1.04 | 1.00 | 0.47 | 0.48 | 0.46 | 0.55 |
Sulfur (%) | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 |
Vitamin A (IU/day) | 80,300 | 83,270 | 75,000 | 75,000 | 75,000 | 75,000 | 24,000 | 24,000 | 36,000 | 75,000 |
Vitamin D (IU/day) | 21,900 | 22,700 | 21,000 | 21,000 | 21,000 | 21,000 | 6,000 | 9,000 | 13,500 | 20,000 |
Vitamin E (IU/day) | 1,168 | 1,200 | 545 | 545 | 545 | 545 | 240 | 240 | 360 | 1,200 |
Adapted from National Research Council. Nutrient Requirements of Dairy Cattle: Seventh Revised Edition. Washington, DC: The National Academies Press, 2001. https://doi.org/10.17226/9825. Reprinted with permission. | ||||||||||
DMI, dry-matter intake; RDP, rumen degradable protein; RUP, rumen undegraded protein; MP, metabolizable protein; NEL, net energy lactation; ME, metabolizable energy; NDF, neutral detergent fiber; ADF, acid detergent fiber; NFC, nonfiber carbohydrates. Trace mineral added to ration: cobalt: 0.11 mcg/g; copper 10–18 mcg/g; iodine: 0.3–0.4 mcg/g; iron: 13–130 mcg/g; manganese: 14–24 mcg/g; selenium: 0.30 mcg/g; zinc: 22–70 mcg/g. | ||||||||||
aMilk components: 3.5% fat, 3.0% true protein, and 4.8% lactose. | ||||||||||
bAll concentrations are on a dry-matter basis. | ||||||||||
cThe maximum energy concentration that can be formulated without resulting in insufficient dietary fiber or excess fat concentrations is 1.8 Mcal/kg dry matter. This energy concentration will typically not meet the energy requirements at this lactation stage, and these cows will lose weight. |