Figure 1. Dairy Ration Formulation Pyramid
There has been a trend for dairy producers to feed higher forage rations over the last 5-10 years. A primary reason is that producers are doing a better job of harvesting and storing larger quantities of high quality forages. The use of the NDF digestibility concept has also provided additional information to assist feed professionals in formulating dairy rations with higher levels of forage. There have also been improvements in the corn hybrids and forage varieties available in terms of NDF digestibility. A key reason for including more forage in the ration in many herds is an attempt to minimize herd health disorders related to feeding high NFC and starch levels in dairy rations.
How do high forage rations work in dairy herds? What about milk production in herds feeding higher levels of forage? To look at this, we asked feed industry professionals to provide some herd and ration information for herds using higher levels of forage. For this paper, a herd is considered a high forage feeding herd if forage comprises > 55% of the total ration dry matter or > 0.9% of body weight as forage NDF (F-NDF). The results from this limited survey are in Tables 1-4. It is important to remember that this ration information is for one point in time in these herds. The quantity of forages fed in these herds over time will vary due to changes in forage quality or inventory.
Table 1. Herd Characteristics of Herds Feeding High Forage Levels
|
Herd |
Year |
Cows |
Group |
RHA
milk, lbs |
Daily
milk
lbs |
% Fat |
% TP |
Times
milked |
|
A |
2005 |
120 |
|
|
75-78 |
3.8 |
3.3 |
2 |
|
B |
2005 |
320 |
|
|
68 |
3.5 |
2.95 |
3 |
|
C |
2005 |
100 |
|
22,000 |
76 |
3.4 |
2.9 |
3 |
|
D |
2005 |
220 |
|
24,000 |
75 |
3.5 |
3.0 |
2 |
|
E |
2004 |
145 |
|
25,500 |
80+ |
3.65 |
2.92 |
2 |
|
F |
2004 |
100 |
|
|
82 |
3.7 |
3.05 |
2 |
|
G |
2004 |
100 |
High |
|
94 |
3.7 |
3.1 |
2 |
|
H |
2004 |
92 |
|
22,000 |
|
3.65 |
3.0 |
2 |
|
I |
2004 |
550 |
High |
29,000 |
100 |
3.6 |
3.0 |
3 |
|
J |
2004 |
60 |
|
25,000 |
78 |
3.7 |
3.1 |
2 |
|
K |
2004 |
60 |
|
|
87 |
3.5 |
3.02 |
2 |
|
L |
2004 |
56 |
|
22,700 |
74 |
3.4 |
2.9 |
2 |
|
M |
2004 |
200 |
High |
|
95 |
3.6 |
3.0 |
2 |
|
N |
2004 |
100 |
|
30,000 |
100+ |
4.1 |
3.0 |
3 |
|
O |
2003 |
100 |
|
|
70-75 |
4.0 |
3.0 |
2 |
|
P |
2004 |
400 |
High |
27,000 |
85 |
3.5 |
2.9 |
3 |
Table 2. Corn silage nutrient composition
|
Herd |
DM |
CP |
Sol-CP, % of CP |
ADF |
NDF |
Lignin |
Sugar |
Starch |
|
A |
28.7 |
7 |
61 |
27.3 |
44.5 |
3.3 |
0.9 |
28.1 |
|
B |
30.4 |
8.5 |
60 |
25.6 |
42.3 |
2.8 |
0.5 |
29.3 |
|
C |
21.2 |
8.3 |
52 |
33.3 |
53.0 |
3.8 |
1.8 |
16 |
|
D |
29.6 |
7.8 |
61 |
25.2 |
43.4 |
3.0 |
1.0 |
30.0 |
|
E |
45 |
7.8 |
56 |
20.1 |
35.6 |
2.5 |
1.2 |
39.6 |
|
F |
31 |
7.8 |
55 |
24 |
40 |
2.9 |
1.0 |
31.5 |
|
G |
29 |
8.5 |
60 |
24 |
38 |
2.7 |
1.2 |
35 |
|
G-
BMR |
26 |
8.6 |
60 |
25 |
40 |
2.3 |
1.1 |
33 |
|
H |
32 |
7.7 |
51 |
|
43.7 |
3.5 |
4.2 |
35.3 |
|
I-BMR |
30 |
8.6 |
55 |
26 |
41.6 |
2.9 |
1.8 |
34.6 |
|
J |
33.7 |
8.2 |
60 |
22.4 |
43.2 |
|
|
|
|
K |
35 |
8.0 |
45 |
26 |
41 |
2.9 |
2.2 |
35.5 |
|
L |
31.5 |
9.1 |
61 |
17.6 |
37 |
2.5 |
3.7 |
39.7 |
|
M |
33 |
8.2 |
67 |
25 |
40 |
3.2 |
0.8 |
35 |
|
N |
35.4 |
7.6 |
61 |
22.4 |
38.7 |
3.2 |
2.4 |
41.1 |
|
O |
31.5 |
9.2 |
48 |
22.0 |
37.7 |
3.2 |
|
34.7 |
|
P-BMR |
26.6 |
9.1 |
54 |
|
40 |
2.5 |
1.1 |
29.7 |
Corn silage nutrient content is fairly similar to other corn silages used in New York. The corn silages in these herds may be a little lower in NDF and higher in starch than other corn silage samples. Only 3 herds were using BMR corn silage (brown mid-rib corn; these hybrids contain a mutation in the gene that controls lignifications of the cell walls. As a result, lignin development is hindered and fiber digestion is much higher than for standard corn hybrids). In one herd (G), a blend of regular and BMR corn silage was fed. Herds I and P were using only BMR corn silage in their high group rations. NDF and starch digestibility data was not available for the corn silage samples in this survey.
Table 3. Nutrient composition of legume and grass forages
|
Herd |
Forage |
DM |
CP |
Sol-CP, % of CP |
ADF |
NDF |
Ligning |
Fat |
Ash |
|
A |
Leg.Sil |
38 |
21.7 |
63 |
28.6 |
34 |
6.45 |
4.2 |
11.5 |
|
B |
Leg.Sil |
44.5 |
24 |
65.5 |
31.2 |
35.6 |
6.4 |
3.9 |
9.1 |
|
C |
Leg.Sil |
36 |
19.8 |
51 |
33.4 |
43.5 |
6.7 |
3.7 |
9.8 |
|
D |
Leg.Sil |
43.7 |
18.9 |
51 |
33.4 |
43.5 |
6.9 |
4 |
10 |
|
E |
Leg.Sil |
41.8 |
22.1 |
53.2 |
33.5 |
41.2 |
6.7 |
3.7 |
11.4 |
|
F |
Leg.Sil |
40 |
20.5 |
60 |
37 |
46 |
7.2 |
4.1 |
12 |
|
G |
Leg.Sil |
35 |
20.5 |
60 |
31 |
40 |
7.9 |
4.3 |
11 |
|
H |
MMG 1 |
26.8 |
21.5 |
62 |
|
49.1 |
9.6 |
|
|
|
H |
MMG 3 |
89.3 |
17.5 |
26 |
|
56.4 |
14.2 |
|
|
|
I |
Leg.Sil |
|
|
|
|
|
|
|
|
|
J |
Grass Sil |
25.6 |
18 |
57 |
32.4 |
49.2 |
4.8 |
5.2 |
10.1 |
|
L |
MML Sil |
33.1 |
17.9 |
56 |
39.1 |
48.8 |
7.7 |
3.7 |
8.9 |
|
M |
Leg. Sil |
32 |
22 |
58 |
32 |
42.3 |
6.8 |
4 |
10 |
|
N |
MML Sil |
28.6 |
18.5 |
58 |
40.3 |
48.9 |
8.9 |
4.1 |
14.1 |
|
O |
MML Sil |
39.3 |
24.5 |
56 |
28.8 |
36.7 |
|
|
|
|
P |
Leg. Sil |
33 |
22.4 |
63 |
|
38.2 |
6.9 |
3.8 |
10.4 |
|
P |
Leg-Hay |
87 |
20.7 |
29 |
|
47.5 |
7.8 |
2.1 |
8.1 |
The herds in this survey were using mainly legume silage or hay. However, some herds used grass (J) or mixed legume-grass (H, L, N, and O) forages. This should not be used to indicate that legume forages are required for herds wanting to feed higher forage rations. This is just the result of the herds provided. Research and producer experience has indicated that high quality grass forages can support high levels of milk production. However, the majority of these forages have slightly lower NDF levels than the average for their forage type. NDF digestibility data was not available for the forages in this survey.
Table 4 contains the ration ingredients used in these herds and the quantities of each included in the ration. Most herds were feeding a combination of corn silage and haylage. Herd K was the only herd with all corn silage based ration. A majority of these herds included some dry hay in the ration. Only 4 herds were using straw in the ration. Some other observations relative to the feed ingredients used are:
Only 2 herds were feeding whole cottonseed.
Most herds were including some type of animal protein or amino acid supplement.
Heat-treated soybean meal was fed in 12 herds.
6 herds included some quantity of urea in the ration.
Tallow was used in 9 herds.
A bypass fat source was used in 5 herds.
Sodium bicarbonate was added to the ration in 12 herds.
A variety of energy and protein sources were used in these herds.
Table 4. Ration ingredient composition (click on table to enlarge)
Click here to enlarge table. 4
Table 5 contains the nutrient composition of the rations fed in these herds. When adequate information was available, the rations were run through the CPM-Dairy model. Body weights used were those provided by the feed professional. If body weight information was not provided, a 2nd lactation Holstein with a body weight of 1400 lbs. was used in the calculations. Key points from Table 5 are:
Forage NDF intake as a % of body weight ranged from 0.85 to 1.16%.
Calculated ration NE-l values ranged from 0.75 to 0.8 Mcal/lb. These values are very similar to NE-l values seen in other herds.
Ration soluble CP levels were on the higher side in these herds.
The proportion of the total MP obtained from microbial protein was > 50% of the total in most herds.
Forage NDF levels (as a % of the total ration dry matter) ranged from 24 to 28%.
The fat levels in these rations were similar to many other rations. Only 3 herds had total ration fat levels > 5%.
Table 5. Ration nutrient composition (click on table to enlarge)
>> Click here to enlarge table. 5
The overall results of this limited survey do indicate that herds with high quality forages are feeding higher forage levels and producing high levels of milk. It must again be emphasized that this information is from a “point in time” in these herds. Many of these herds continue to feed these higher forage levels when quality and quantity are adequate.
What are the risks or potential challenges in feeding higher forage rations to dairy herds? As with any management practice, there are always some considerations that need to be evaluated. Some of the most common ones for herds desiring to feed higher forage rations include:
A large supply of consistent quality forage is required. As higher forage rations are fed, less energy and protein is provide from the grain mix. Thus, variations in forage quality may be more evident since there is ability to adjust for forage quality variations via the grain mix.
Feeding and feed bunk management must be excellent to assure that fresh, high quality forages are always available.
More forage inventory and storage capacity is needed for the same number of cows. Total yearly forage needs can increase by 15-30% when higher levels of forage are fed. In some herds, it may take a number of years to match crop rotations and forage management practices to provide this quantity of forage.
Routine forage inventory or forage use evaluations need to be made. This will prevent running out of forage early before the next forage harvest season.
More attention to forage storage and allocation may be needed. Very few herds have only “high quality” forages available. Planning may be required to store forages by quality at harvest. Allocating specific forages or silos to specific animal groups during fadeout may also be required to obtain the best response from these higher quality forages. The ability to store and feed forages by quality is a problem in some herds.
The herds in this survey were all feeding stored forages. Herds using pasture were not included since “estimating” pasture forage intake is difficult. However, many pasture herds using rotational grazing will have higher quality forages than those listed in Table 3. The “predicted” forage intake in these herds will often be even higher than the ration forage levels listed in Table 4. Research data indicates that cows on pasture will often have forage NDF intakes that are > 1.2% of body weight.
Feeding higher forage rations is an opportunity that should be considered in our dairy herds. The herds in this survey do confirm that this approach can work. However, the key is to have adequate quantities of consistent, high quality forage available on the farm. The potential of feeding higher forage rations should be evaluated on most farms. In some herds, this move will take a number of years due to shifts that need to be made in cropping, forage harvesting and forage storage. The long-term potential benefits include higher levels of milk components and better herd health. A more in-depth analysis of herds is needed to better quantify these relationships. |