As mentioned earlier, forage is
an extremely important part of the diet of all horses
and ponies and has three functions:
- Contains digestible fibre broken
down by the microbial population in the hindgut
to provide energy.
- Provides indigestible fibre
or roughage to help maintain gut motility and efficient
digestion.
- Meets the horse's psychological
need to spend a significant proportion of his time
chewing.
FRESH FORAGE may be provided
as fresh grass from the pasture (avoid feeding grass
mowings or clippings as they may cause major digestive
disturbances and can cause serious gas or impaction
colic.)
PRESERVED FORAGE may be provided, either in long fibre
form as hay, haylage (semi-wilted, fermented grass in
bags) or in short chopped fibre form commonly known
as chaff.
Long Fibre
HAY is the most traditional method of preserving grass
for horses. Meadow hay is made from established 'old'
or 'permanent' pasture, which has developed a wide variety
of different grasses and other species. Seed hay is
cut from fields of especially sown grasses or 'leys'.
Seed hay leys are usually a maximum of three years old
and normally contain only one or two grass species.
Threshed or Thrashed Hay
When grass is grown to produce grass seed, the threshing
or thrashing process removes the seeds and the stalks
are left to dry. These stalks and the limited amount
of leafy material are baled as threshed or thrashed
hay. The nutrient levels in this type of hay are often
rather low as the grass is usually quite mature and
stalky when the seeds are ready for threshing.
Mould Contamination in Hay
Recent surveys suggest that up to 80% of hay made in
the British Isles contain significant amounts of mould
contamination usually caused by too much moisture when
baling. Dusty and mouldy hay is probably the single
greatest cause of allergic respiratory disease in horses
and it aggravates the symptoms of infectious respiratory
disease. Thus many people are looking for alternative
sources of forage.
Grasses and Plants of English Hay
Soaking Hay
Many people soak hay, hoping the spores will be washed
out or 'stick to' the plant material and be swallowed
rather than inhaled. However, as the hay dries the spores
again become airborne and are inhaled. In addition research
has shown that there are significant nutrient losses
when hay is soaked.
Barn Dried Hay
Rather than drying hay in the field, barn dried hay
is cut, wilted in the field, and then further dried,
usually for 7-10 days, by fan-driven air in a barn.
Because of the additional handling and air drying costs,
barn dried hay is often in short supply and is expensive.
Semi-wilted, Bagged Forage
A method of preserving grass which overcomes all the
problems of dust and mould in hay is semi-wilted forage.The
leading brand is HorseHage which is grown and produced
specifically for feeding to horses. It is made from
selected quality grass (seed leys) cut and turned just
like hay but, instead of being allowed to dry completely
on the field, it is baled when the grass has wilted
and the moisture content is between 35 and 45 per cent
(55-65% dry matter). This takes around 24 hours in good
drying weather.The bales are then compressed to half
their original size and heat sealed into tough double-skinned
plastic bags. No artificial preservatives are added,
and natural fermentation inside the bag prevents the
development of fungal spores and preserves the grass.
Grasses and Plants of English
Hay
Once the bags have been sealed to exclude air, naturally
present bacteria and yeast start to break down the
sugars - a process called fermentation - in order
to preserve the grass and retain maximum nutrient
levels.
The aim of the HorseHage manufacturing process is
to encourage a mild lactic fermentation brought about
by the presence of the beneficial micro-organisms
such as lactobacilli. This reduces the pH, that is,
naturally produces a slightly acid environment sufficient
to prevent the activity of harmful organisms, and
it is this fermentation which gives HorseHage its
characteristic attractive smell.
The problems of nutrient loss from fresh grass during
traditional hay-making, and the unsuitability of most
silage for horses, are well documented. Due to the
special method of preservation, HorseHage retains
up to 90% of the feeding value of fresh pasture.
HorseHage Production Process
Unlike some semi-wilted forage or silage, no acid
additives are used in the production of HorseHage
- mould growth is prevented by the method of production
and hence is naturally inhibited.
Semi-wilted bagged forage is so effective at preventing
allergic respiratory disease that many owners feed
it for this reason alone. In this way they avoid respiratory
problems which might otherwise prevent a horse from
reaching a required level of fitness, which in turn
would badly affect its performance. Recent research
has shown that dust-free bagged forage usually provides
a higher level of digestible fibre than most hay samples
and thus bagged forage can provide a greater proportion
of the horse's energy requirements. This allows a
reduction in the energy needed from concentrate feeds
and helps to prevent starch overload disorders. Furthermore,
bagged forage retains the naturally present B complex
and other vitamins which are usually lost within weeks
of making and storing conventional hay due to exposure
to sunlight and oxygen. The B complex vitamins are
important in:
- Feed utilization
- Stimulating appetite
- Synthesizing certain components
of blood
Other advantages are that
bagged forage, such as HorseHage, is supplied in several
types, i.e. Ryegrass, High Fibre, Timothy and Lucerne
(Alfalfa) with nutrient values to suit different horses.
Most importantly, unlike hay, it provides a consistent
nutrient value. It is therefore much easier to assess
how much concentrate feed is needed to provide the required
energy and a balanced diet.
Big Bale Haylage
Big Bale Haylage is made in a similar way to semi-wilted
bagged forage, but in bales weighing up to half a tonne,
and rather than being bagged, the bales are wrapped
in several layers of plastic. Due to their size the
bales are difficult to handle and impractical for most
horse owners, as once opened the bale needs to be consumed
in 3-5 days. They also tend to be higher in moisture
and more difficult to compress, leading to poor fermentation.
Silage
Clamp silage is made by cutting grass and usually taking
it off the field immediately while still 'wet'. The
grass is put into a specially built pit or clamp and
compressed by rolling - usually with a tractor. It is
then covered in plastic, weighed down with old tyres.
Additives or chemicals may be used to encourage a rapid
fermentation to preserve or 'pickle' the grass. Silage
may also be made in large round bales. Generally silage
is not suitable for feeding to horses, since the moisture
level is usually too high, with a low pH, a low fibre
and high protein level.
| Nutrient |
Ryegrass
Mix
Bagged
Forage |
High
Fibre
Bagged
Forage |
Timothy
Bagged Forage |
Lucerne
(Alfalfa)
Bagged
Forage |
Seed
Hay |
Meadow
Hay |
| Dry
Matter % approximately |
55 |
55 |
55
|
50 |
85-92 |
84-90 |
| Protein
% |
9-12 |
7-10 |
8
– 9
|
12-15 |
4-12 |
6-12 |
| M.A.D
Fibre% |
32-36 |
34-40 |
35
– 37 |
38-42 |
30-42 |
30-40 |
| Estimated
Digestible Energy MJ/kg |
9-11.5 |
7-10 |
8 – 10 |
7-10 |
7-11 |
8-11 |
| Calcium
g/kg |
2.5-4.0 |
2.5-4.0 |
2.5 – 4 |
8.0-10.0 |
2.5-4.0 |
2.5-4.0 |
| Phosphorus
g/kg |
1.7/2.5 |
1.7/2.5 |
1.7 – 2.5 |
2.0/4.0 |
1.6/2.5 |
1.6/2.5 |
| Magnesium
g/kg |
1.0 |
1.0 |
1 |
2.4 |
1.0 |
1.0 |
| Copper
mg/kg |
6 |
6 |
6 |
10 |
4 |
6 |
| Zinc
mg/kg |
16 |
16 |
16 |
26 |
16 |
16 |
| Manganese
mg/kg |
32-70 |
32-70 |
32 – 70 |
40 |
30-70 |
30-70 |
| Beta
Carotene mg/kg |
100 |
50 |
50 |
13 |
|
|
| Vitamin
E mg/kg |
35 |
35 |
10 |
12 |
|
|
| Vitamin
B1 mg/kg |
2.0 |
2.0 |
2 |
2.1 |
|
|
| Vitamin
B2 mg/kg |
3.2 |
2.8 |
3 |
2.2 |
|
|
| Vitamin
B6 mg/kg |
6.0 |
6.3 |
6 |
7.0 |
|
|
| Niacin
mg/kg |
23 |
23 |
20 |
24 |
|
|
| Pantothenic
Acid mg/kg |
21 |
17 |
17 |
30 |
|
|
| Folic
Acid mg/kg |
0.6 |
0.6 |
0.6 |
0.8 |
|
|
| Biotin
mcg/kg |
60 |
60 |
60 |
11 |
|
|
 |
= Vitamin levels will deteriorate
with prolonged or poor storage |
The above table is continued below. |
| Nutrient |
Lucerne
(Alfalfa)
Hay |
Big
Bale
Haylage |
Silage |
Hydroponic
Forage |
Molassed
Chaff |
Dried
Alfalfa
Chaff |
| Dry
Matter % approximately |
88-91 |
48-65 |
35-65 |
15-20 |
80 |
90 |
| Protein
% |
6-18 |
8-12 |
8-18 |
16-18 |
4-7 |
16 |
| M.A.D
Fibre% |
34-43 |
32-42 |
30-42 |
12-16 |
20-30 |
30 |
| Estimated
Digestible Energy MJ/kg |
6.5-11.5 |
9-11.5 |
8-12 |
10-12 |
6-9 |
9-11 |
| Calcium
g/kg |
6.0-12.0 |
2.5-4.0 |
2.5-4.0 |
1.0 |
|
8-13 |
| Phosphorus
g/kg |
2.0/4.0 |
1.6-2.5 |
1.7-2.5 |
4.5 |
|
2.0-3.5 |
| Magnesium
g/kg |
2.4 |
1.0 |
1.0 |
1.4 |
|
2.4 |
| Copper
mg/kg |
10 |
6 |
6 |
8 |
|
10 |
| Zinc
mg/kg |
26 |
16 |
16 |
34 |
|
26 |
| Manganese
mg/kg |
40 |
30-70 |
30-70 |
30 |
|
40 |
| Beta
Carotene mg/kg |
80 |
100 |
100 |
|
|
85 |
| Vitamin
E mg/kg |
45 |
35 |
35 |
|
|
45 |
| Vitamin
B1 mg/kg |
2.0 |
2.0 |
2.0 |
|
|
2.0 |
| Vitamin
B2 mg/kg |
5.0 |
3.0 |
3.0 |
|
|
5.0 |
| Vitamin
B6 mg/kg |
5.0 |
6.0 |
6.0 |
|
|
5.0 |
| Niacin
mg/kg |
25 |
20 |
20 |
|
|
25 |
| Pantothenic
Acid mg/kg |
15 |
20 |
20 |
|
|
15 |
| Folic
Acid mg/kg |
0.7 |
0.6 |
0.6 |
|
|
0.7 |
| Biotin
mcg/kg |
12 |
60 |
60 |
|
|
12 |
|
= Mineral and vitamin levels
may vary if nutrients are added to the water. |
|
= Mineral and vitamin levels
vary according to manufacturers additions. See
bag label for details. |
All figures in the tables
above represent typical analysis.
General Points about Bagged
Forages
Bagged forage especially for horses, big bale haylage
and silage all depend for preservation upon successful
fermentation in the controlled environment of their
plastic packaging. However when over 50% moisture
is present (see the chart below) the fermentation
cannot be relied upon to produce suitable forage for
horses.
Typical Moisture Content of Forage Products
At best it may result in very acidic forage with high
ammonia levels, which is unpalatable and has potentially
undesirable metabolic effects. At worst it may allow
the proliferation of undesirable micro-organisms,
i.e. the clostridial bacteria which can cause the
usually fatal disease, botulism.
Short Chop Fibre
Short fibre forage can be used as a hay replacer but,
because it takes only a short time to eat, it is more
often used to bulk out concentrate feeds.
Molassed Chaff
Good quality molassed chaff is made from hay and/or
straw which is chopped to a short length, dust extracted
and mixed with molasses to provide a highly palatable
feed. It is available with different nutrient values,
and a choice of added herbs, minerals and vitamins.
Chopped Dried Alfalfa
A more recent product is chopped dried alfalfa, also
available with added oat straw to give higher fibre.
Both kinds are mixed with molasses to increase palatability
and to control the dust. Once cut, the alfalfa is
placed into a drum drier where a temperature of 800
degrees celcius quickly reduces the moisture content
from around 75 to 10 per cent. This rapid high temperature
drying retains nearly all the original feed value
of the crop. Chopped dried alfalfa has a higher nutrient
value than molassed chaff, and with pure alfalfa hard
feed quantities can often be reduced.
Hydroponic Forage
Another alternative to hay is hydroponic forage, which
is the fresh shoots of germinated barley seeds grown
in a controlled environment and fed at around five
days growth. As with vacuum cleaned hay it involves
the purchase of special equipment and, if not properly
maintained, there is a risk of mould contamination.
As fibre levels of hydroponic forage are very low,
in practice it is generally regarded only as a supplement
to the diet.
Alfalfa Hay
Yet a further alternative to traditional hay is alfalfa
hay, also called lucerne, which is imported to this
country mainly from America. Alfalfa is a legume -
a tall green plant with a purple flower that is made
in the same way as hay, but provides a greater source
of nutrition. At present alfalfa hay is available
in only limited supplies and is very expensive.
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