Table 5

Theoretical Amounts of Dry Matter Intake Required to Meet the Energy (TDN) Requirements of a 1200 lb Lactating Beef Cow Producing 20 lb Milk Per Day When Grazing Crested Wheat grass with Different Protein and Energy Concentrations

 Date of Sampling

 Avg. Crude Protein, %

 Avg. IVDMD, %

 Dry matter intake required to meet  TDN requirements for a 1200 lb lactating cow, %BW

      May

23.27

56.77

2.3

      Late May

19.77

50.20

2.9

      Mid June

18.33

45.30

3.5

      Late June

15.60

46.23

3.4

      Mid July

13.90

44.43

3.6

      Mid Aug

11.73

40.97

4.5

      Sept

9.70

38.00

5.4

      Late Oct

9.30

34.33

7.7