A. - Opening the silo
One may open the enclosure and starting feeding the treated forage to the animals after three or even two weeks in tropical regions, or after three to five weeks in the Mediterranean region and in tropical regions at altitude having fresh climates.
The farmer may also prefer to postpone using the forage and keep it for feeding later. It can remain in the enclosure for several months under the condition, obviously, that it is well protected from the weather and from infiltration by water. The farmer may also withdraw the treated forage from the enclosure and store it elsewhere, but it must be dried first. He could then place it in a grain store, a building or in the stable, sheltered from the sun and the weather and clearly, so that the animals cannot reach it. By storing the forage in this manner, the treatment enclosure may be used again for additional treatments, but at cost of considerable additional labour. It could be preferable to prepare two or even several treatment enclosures.
Successfully treated forage will present the following characteristics:
a strong pungent smell of ammonia
a dark colour, ochre brown to maroon
a soft and supple texture
an absence of moulds
B. - Method for utilisation
1) The animals concerned:
The treated forage is rich in non-protein nitrogen which may be used by the rumen's microbes (see Chapter 1). These microbes only exist in functional ruminants, which means to say, those which already feed from forages and which ruminate; thus the treated forage should only be fed to animals which are ruminants:
cattle and buffalo (cows, heifers, bullocks, oxen), sheep, goats, camels.
One must be sure when feeding young animals that these are already accustomed to eating forages and that they ruminate.
2) Allowing for a period of adaptation
A period of about two weeks should be allowed for the microbes in the animal's rumen to become adapted to the non-protein nitrogen and to avoid risk of food poisoning. During this period, the treated forage should gradually substitute the natural forage so that after two weeks, natural forage is no longer the only feed provided and the new ration has been introduced in its entirety.
3) Feeding and rationing
Once the daily forage ration has been taken out of the silo, the enclosure or the stack, it is advisable during the period of adaptation, to leave it to air throughout the day. This allows:
evaporation of the ammonia which has not been fixed and which thus renders the treated forage less bitter to the taste of the animal,
avoiding any eventual overload of ammonia for the animal in the event that the treatment was undertaken with very damp forage. In effect, as the ammonia has great affinity for water, it will be adsorbed more when the forage is moist.
However, once the animals have become accustomed, farmers generally find that they can feed the treated forage directly after it has been taken out of the silo, without resorting to airing it.
An important point: do not be worried if the animal rejects the forage during the first few days. One should persist without becoming discouraged as it only means that the animal is still not used to this type of forage. Once it has become accustomed to it, it is the natural forage which it will reject!
In case of more serious difficulties due to an overdosage (forage which is too brown, too moist and with a very strong smell of ammonia), there are two possibilities:
either mix the treated forage half and half with natural forage, if the amount of treated forage stored is considerable and one does not wish to lose it,
otherwise, reject it if only a small amount is involved.
4) Rationing
Depending upon how much treated forage is held in stock, rationing may consist,
either, of only an essential proportion or alternatively, it may constitute the only ingredient of the basic ration for distribution ad libitum to the draft animals, the beef or the dairy cattle,
otherwise, it may constitute a supplement for the pasture and so should be given in limited quantities to the animals when they return from grazing.
There is no harm in distributing the treated forage without any concentrates. However, in this case one will not be able to obtain full benefit from the treatment. The minimum supplement to ensure profiting well from the treatment consists in a mineral supplement.
If the livestock farmer already has the habit of adding supplements to his non-treated forage, he may now:
either, reduce the amount of these supplements so as to economise. The improvement given through treating the forage will allow him to maintain the production rates of his animals;
or, he might continue giving the same supplements (and so increase production levels). But it would be wiser, if these supplements consist of commercial concentrates, to substitute them for supplements such as bran, cotton seed or cake, etc. Whatever is the situation, it is most important that this supplement should not contain any urea, a non protein source of nitrogen which has already been supplied during the treatment.
5) Additional precautions
Apart from the recommendations outlined above it is convenient to respect the following points:
never lend treated straw to a neighbour if his animals are not accustomed to feeding from treated forage,
on each occasion that feed supplies to the animals of the treated straw are interrupted for a few days, a new period of adaptation must be allowed for, once feeding this material is recommenced. It is preferable, once feeding treated straw has been started, that this should be continued without these interruptions which will hinder the overall good utilisation of the stock. The feeding habits of the ruminant, in effect, should be as regular as possible if they are to be efficient.
because the solution of urea is very concentrated and toxic, one must never offer it to an animal as drinking water and never leave it unattended. Any excess solution left over after treatment should be disposed of. All equipment and material which has been used (receptacles, buckets, jars,…) should be washed and the hands rinsed, as urea is also toxic for humans.
avoid treating damp forages which can bring about an overdosage or poor incorporation of the urea with the forage. In case of need, adjust the amount of urea in function to the moisture content (5 % of urea on a dry matter basis for the forage).
whilst the urea is being dissolved in the water, a cooling effect occurs and the solution can become quite fresh: never try to take advantage by cooling soft drinks or other consumable products, such as fruit, etc.
