
Livestock: August 2002
|
I know what some of you are thinking right now: "This guy is crazy. 'Making' hay
is 'feeding' hay, you just do it at different times of the year." Well, I may
be crazy, but itÍs not because I contend that making hay is not always feeding
hay. The mindsets behind these two actions are sometimes as different as night
and day. Therefore, before making and feeding hay can be considered synonymous,
there are a few considerations to keep in mind.
Fortunately, most of the FoundationÍs service area has been blessed with
adequate rainfall (if there is such a thing) and mild temperatures this spring
and early summer, kicking pasture production off right. In many instances, we
have actually witnessed an overabundance of forage production for grazing
purposes, and so have recommended baling the excess to be used at other times
of the year or to sell. In any case, most, if not all, of this hay will wind up
in front of some class of livestock ? so nutritive value must be considered at
the time it is baled as well as when it is fed. The most important factors
affecting the nutritive value of hay are moisture content at baling, length and
conditions of storage, maturity at cutting, and forage species present.
Moisture content at baling and storage characteristics add considerably to the
nutritive value of the hay and are often at the control of the operator.
Excessive moisture content (greater than 22 percent) at baling is usually only
an issue when it results in significant hay spoilage or a barn fire. However,
baling wet hay results in a significant reduction in nutrient value along with
losses in dry matter production (Table 1), which are detrimental when feeding.
A natural event, commonly referred to as "heating," occurs when growing forages
are cut and continue to give off heat due to respiration. This particular heat
is of little consequence except to provide proper growing conditions for
bacteria, and will subside as the moisture content of the forage drops during
the curing process. But, if hay is baled too wet, microbe populations flourish
and exacerbate the heating process, resulting in hay that is lower in nutritive
value and dry matter availability (Table 1). In extreme cases, it results in
significant losses due to hay and/or barn fires.
| Table 1. Dry Matter and quality loss (% of initial crop yield) at
different hay storage moisture values1. |
Storage
Moisture
|
|
Dry Matter
Loss
|
|
Digestible Dry
Matter Loss
|
|
Crude Protein
Loss
|
|
11 to 20%
|
|
4.5%
|
|
6.2%
|
|
6.0%
|
|
20 to 25%
|
|
7.9%
|
|
11.8%
|
|
8.8%
|
|
25 to 34%
|
|
10.9%
|
|
13.5%
|
|
7.5%
|
1 Taken from extension publication FO-07404-GO, 1999,
" Preserving the value of dry stored hay," University of Minnesota
Extension Service. |
Moisture levels for safe storage vary with the size and density of the bale and
the type of hay. Hay in small square bales should be baled between 15 and 22
percent moisture to minimize leaf shattering, molding and heating. Larger bales
retain core moisture, thus internal heat, longer and should not be baled at
moisture levels in excess of 18 percent. If baling hay with more than 22
percent moisture is necessary, do not stack for at least 30 days and consider
this fact when feeding.
Large bales stored outside will suffer variable losses, depending on the
moisture of the hay at baling, the extent of exposure to precipitation, soil
drainage characteristics where the bales are stored, the amount of space
between the bales, and the type of hay. Store properly-baled hay in a
well-drained area, a minimum of three feet between bale rows, away from trees
or shade, and in the same direction as prevailing winds (north and south). Now
that the hay is put up right, letÍs jump ahead six months and talk about
feeding it right. First and foremost, ask yourself, "What will be the nutrient
demands (Table 2) of my cattle at feeding?" These demands will be influenced by
stage of lactation, mature weight, frame size, breed and weather conditions.
Furthermore, ask yourself "How is the existing forage base (quality and
quantity) going to contribute to the feeding program?"
| Table 2. Requirements of beef cows during different stages of
production. |
| |
|
|
|
|
|
Trimester of Gestation
|
Cow
Weight |
|
Milking
Ability1 |
|
|
Peak Milk
Yield2 |
|
1st |
|
2nd |
|
3rd |
| |
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
DMI (lbs/d) |
24.80 |
|
23.53 |
|
21.00 |
|
21.07 |
| 1000 |
|
Average |
|
CP (%) |
10.70 |
|
8.89 |
|
6.20 |
|
7.76 |
| |
|
|
|
TDN (%) |
59.70 |
|
55.47 |
|
45.87 |
|
52.27 |
| |
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
DMI (lbs/d) |
27.33 |
|
25.00 |
|
21.00 |
|
21.07 |
| 1000 |
|
High |
|
CP (%) |
12.31 |
|
10.07 |
|
6.20 |
|
7.76
|
| |
|
|
|
TDN (%) |
63.13 |
|
57.97 |
|
45.87 |
|
52.27
|
| |
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
DMI (lbs/d) |
27.67 |
|
26.53 |
|
24.10 |
|
24.20 |
| 1200 |
|
Average |
|
CP (%) |
10.24
|
|
8.57 |
|
6.22 |
|
7.84 |
| |
|
|
|
TDN (%) |
58.73 |
|
54.77 |
|
45.93 |
|
52.60 |
| |
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
DMI (lbs/d) |
30.20
|
|
28.00
|
|
24.10
|
|
24.20
|
|
1200
|
|
High
|
|
CP (%) |
11.72
|
|
9.64
|
|
6.22 |
|
7.84 |
| |
|
|
|
TDN (%) |
61.87 |
|
57.07 |
|
45.93 |
|
52.60 |
| |
|
|
|
|
|
|
|
|
|
|
|
1Average= approximately 15 to 20 lbs./d milk yield
(Angus, Hereford) High= >20 lbs./d milk yield (Simmental, Gelbvieh)
2 day 0-90 post-calving
|
| |
|
|
|
|
|
|
|
|
|
|
|
| Taken from "Nutrient Requirements of Beef Cattle,"
7th Revised Edition, 1996 (Nat'l. Academy Press) |
This information will yield insight into the quality of hay needed to be most
efficient through the feeding period. Use the information discussed above to
your benefit: observe where the hay has been stored, look for excessive mold,
ask for nutrient (protein and energy) values, and ask if weights were taken.
Instead of making the transaction solely on a per bale basis, implement the
answers to the above questions so you can meet feeding goals most effectively.
When hay producers are willing to collect and provide this type of information,
and livestock producers ask for it and use it, then "making" and "feeding" hay
become one and the same.
Note: If you are in the market to buy, or have hay to sell, visit the "Hay
Listings" section of our Web site at http://www.noble.org/ag/Cattlelog/Index.asp
to facilitate the transaction.
|