Silage Preparation and Forage Plants
The main sources of feed for the cattle and ovine in our country are comprised of natural pastures, field plants production residues and forage plants such as vicia sativa, clover and trefoil that are grown within the scope of field agriculture. Apart from this, growing silage plants has also become rapidly more common with the impact of the incentives provided for silage making. In our country, when the animals are examined, it can be seen that the number of highly efficient cultural races and hybrid animals constitute a significant place. In order to obtain higher efficiency from the animals, good care and feeding conditions are a must. Within this care, in terms of animal breeding, high quality silage has a particularly significant place. In those enterprises, where there is informed breeding carried out, silage is an important implementation that increases efficiency in animal feeding.
Silage is a feed that is obtained through the fermentation of feeds, which are rich in water, in an airless medium, with the impact of milk acid bacteria. Silage in short is defined as the animal pickle. The place where the silage is kept is called the silo or the silage pit.
In our country, during the recent years, the meat and milk efficiency per animal has increased. Within this increase, it is known that the gramiane and corn silage had a significant role. Particularly, in humid regions, the problem related to the drying of grass and most plants being able to easily ensiled has increased the silage production. Storing the plants with only a small amount of loss in terms of their nutritional substances, not having them affected from weather conditions, as they are appropriate for mechanization and the reduction in the losses related to harvesting and delivery and the fact that the well done silages could last for long periods of time have all contributed to the silage’s field of utilization becoming more common.
Even though almost all of the plants can be used to make silages, most common practice is corn silage. Forage plants such as clover, shamrock, vicia sativa are also used to make silages while the organic acids, minerals and proteins in these plants are higher and therefore as their sugar levels are lower, it makes them harder to ensile.
Corn is considered as a perfect silage plant all over the world. The planting fields for corn, which has a multidirectional field of utilization, have increased in the recent years for the purposes of green feeds and silage production. The high efficiency levels of corn silage are appropriate for silage production and the silage obtained have high levels of nutritional values and therefore they are preferred more. As corn is a hot climate plant, it can be planted at the beginning of spring and summer. Depending on the size of the seed, it would be enough to use 2-2.5 kg of seeds per decare. In the production of sweet corn, planting is done as 8-9 thousand plants per decare and for the silage corn, these numbers can go up to 12-14 thousand. During the planting, the row spacing should 70 cm, while on the row 10-12 cm is recommended. The most significant advantages of corn include the high levels of digestion and the high levels of efficiency obtained from unit area. In our country, in those regions, which have shore and mountain climate, after the harvest of grains (barley, wheat), corn is grown as the second product planted as silage feed. The types of corns that are planted for ensiling should be tall, multifoil, with high numbers of seeds on the corncob and heavy cob. As the second product, corn that is planted in those regions should be planted early.
During the ensiling of corn, additional additives are not required as much. The quality of the corn silage is determined by characteristics such as type, time of harvesting, cob rate, piece dimension, form of silage, filling time and degree of compaction. In general, the highest dry matter efficiency in corn is obtained from the forms that are carried during the milk making and dough making stages. During this period, the dry matter rate is around 30-45% and they have the most appropriate levels for silage. The digestion of dry matter and the voluntary feed consumption of the animals are highest at this stage.
Harvesting Plants and Filling Them To The Silage
Good silage production first of all requires the plant that would be ensiled, to be sown in an appropriate period. When the humidity rate is between % 60 – 67, plants may be harvested and ensiled. The silages divided into smaller pieces are more consumed by animals. In this regard, the size of the silage material should be 0.6-2.5 cm in normal silages, while it has to be 0.6-1.2 cm in faded silages. The plant that would be ensiled should be broken down to pieces so that it can increase the quality, have a better pressing and more feed is stored in a unit area. The plant material that has been broken down can be easily carried to be filled in the silage and pressed. The pressed plant material shall be covered with PE or PVC plastic covers. On the silage that has been covered, weights such as old car tire, grass bale or sandbag are placed. The filling and pressing processes should be completed as soon as possible and the silage has to be closed. The silages that are kept open for a long period of time will have dry matter loss and they may also be decayed or have molding due to negative environmental conditions.
Fermentation of The Silage And Ripening
In order for green plants to be kept in the silage without any decay, the medium pH should be reduced as soon as possible and to a level where the microorganisms that lead to the decay of the silage cannot work. In general silage will ripen 7-8 weeks later and can be given to the animals after this time. The ripened silage may be given right away as a feed or it can be stored for 2 years (considering it does not get any air).
In order to minimize silage losses, the silo has to be closed really firmly and until the silo is opened the covering layer should be regularly checked. When the silo is opened, air will enter inside the silage and the largest dry matter and nutritional losses will take place in the silage during this phase. The silage that takes in air will have bacteria, molds and yeasts. Firmly pressed silage that does not have any gaps between feeds and that is closed well will have minimum levels of losses as the air will not be able to enter easily. In exchange for this, the silages that are prepared with low levels of humidity cannot be pressed well and therefore the airflow can easily affect the whole silage. After the silo is opened, fast consumption will reduce the losses significantly and those silages that are kept open for a long time and slowly consumed shall have increased losses.
Properties of The Silage and The Measurement of Feed Values
The color of the silage may change depending on the plant it is made from and it can range from light green to darker tones. The silage has to have a pleasant smell, it should not have unwanted butter acid and mold smells. The stems and leaves of the plants should remain intact, they should not have a sticky appearance. The feed value of the silage first of all depends on the type of the feed, planting time and ripening levels. Apart from this, ensiling technique also influences the value of the feed. The reduction of silage quality, are due to the formation of unwanted butter and vinegar acid bacteria that occur as a result of excessive heating. The estimation of the feed properties of the silage is carried out through physical and chemical methods. The determinations conducted through physical methods are conducted with the use of sense organs. In this regard, the smell is considered as the most determinant physical property of silo feed. Apart from this, dry matter and pH values are important indicators of quality. Physical method is important as it allows the silage to be evaluated rapidly and in a practical manner at the facility.
The additives that will be added to the silage are different products that are used to develop fermentation, reduce ensiling losses and to increase the efficiency performances of animals that consume these silages. Additives do not transform a bad silage into a good silage. Only a good silage will become a better silage. The additives used during ensiling are as the following.
Carbohydrate sources: The plants sown for silage do not always have the appropriate humidity levels and carbohydrate amounts. The constant fermentation in silo becomes harder. For this reason, particularly the ensiling of green material, which has high levels of humidity and low levels of carbohydrate that could be fermented, various additives will be used. Corn, barley, oat, bran, crushed grains and various grain flours are included within this group. The grain forages such as barley, wheat and corn, which are rich in carbohydrates are recommended to be used by 1-4% depending on the carbohydrate content of the silage material during the silage preparation stage.
Additives that reduce the water content of forages: If the forages have to be ensiled when their water content is high, then the silo has to be added with materials that would suck the water. For this purpose, the most commonly used additives are dry beet pulp and wheat bran. These should be added in 25-30 kg within a ton of silo forage. Substances such as stems and hay are not suggested as long as they are not mandatory given that they reduce the quality of the silage.
Salt:Green forages have low levels of sodium and therefore they do not fulfill the needs of the animals. For this, salt has to be added to silo forages. Even though the impact of salt on fermentation is not high, given that it has a bactericide effect, they can be added between 1-3% to the silage. Granulated rock salt is recommended for adding to the silo forages. They also prevent molding on the edges of the walls of the silage pits and at the top of the silage.
Furthermore, there are also silage additives that are sold commercially. These ensure the reduction of the pH of the silage due to the organic acids in their content. This way, molds and fungi are prevented. They ripen the silage in a short period of time.
What Are The Points That Have To Be Taken Into Consideration When Feeding With Silage?
Silages have to be given in a manner that they will at most fulfill 1/3 of the total dry matter needs of the animals. For example, if an animal’s daily dry matter requirement is 15 kg, then 5 kg of this can be given as silage. If this requirement is to be fulfilled with the silage that is comprised of 25% dry matter, then the silage has to be given in 20 kg. When the animals are given silages, there has to be a transitional period for passing onto feeding with silage, making sudden forage changes should be avoided. If the molded silages are fed to the cattle, there will be aflatoxine in the milk and this would cause the producer to lose money. Usually, molded forage raw materials are given to cattle animals, however at this point they pass onto the meat.
If the cellulose level of the silage is low, then together with the silage, dry grass has to be also given. During the dry period, silage should not exceed 3-5 kg a day. Silage should not be given to cows that are smaller than 3 months old. Feeder cattle can be fed with 3-4 kg silage on average. Giving the feeder cattle corn silage, which is rich in energy, is more beneficial in terms of feeding value and the management economy. However, high levels of corn silage may cause yellow colored seborrhea under the skin in feeder animals due to the color pigments in its content. Those animals that eat excessive amounts of silage will have salt and calcium deficiencies and a risk of acidosis. Excessive amounts of silage should not be taken out the silo and kept for the feeding time. During this period, particularly during hot summer days, as there is a loss of humidity, dense smell of acid is also observed. After the amount of silage that will be given to the animals is taken out of the silage pit, then the region where the silage is taken from should be covered again with plastic. Baby cows should be given the silage after they complete their rumen development (after they start eating stems, hay or dry grass). This should usually start with those animals that are older than 6 months old. Pregnant animals at their advanced stages should not be given silage. However, for the purpose of completing the farm ration a small amount may be given.