Feed composition greatly affects the ability of piglets during the weaning from the sow to digest food. The use of extruded cereals in this sensitive phase of the animal acting on them supportive. These grains are digested better, and promote intestinal health, said Dr. Haynrih Klyayne Klausing from Dusseldorf.
After weaning from the sow comes to asking for decisive change in the composition of food: from the "liquid feeding" the sow's milk, characterized vysokoperevarimym protein, fat and lactose, Power, consisting, first of all, starch from cereals and vegetable protein. Simultaneously changing the activity of various digestive enzymes, first and foremost activity is important for the digestion of amylase starch (cm. schedule "Production of enzymes after weaning").
By the time otlucheniya activity has amilazы, chymotrypsin and lipase short term decreases from one quarter to one fifth. Two weeks after weaning the concentration of lipase everything is also low, chymotrypsin and amylase activity returned only to 70 и 74 percent respectively of their activity at the time of weaning, respectively. This situation should be taken into account in the composition of compound feed for pigs and selection of raw materials for them.
To corn starch at significantly limited amylase activity could be digested by enzymes in the small intestine preferably, it is possible to "open" cereal starch feed before feeding through intensive technical processing. With this and related "productivity effect" and increased feed intake due to better its digestibility. Кроме того, so it prevented from being excessively large amount of undigested starch in the large bowel. Allowing the development of potentially dangerous E. coli significantly reduced, as well as the risk of diarrhea.
Technology to "open up" the starch
For the processing of grain in order to "open up" the starch in practice use different technologies. The thermal method (eg, infrared radiation, processing with hot air) It is to use these factors influence, the temperature and duration of exposure. In the hydrothermal method, (eg, toasting) additionally used moisture. The combination of hydrothermal processes (factors of influence: temperature, moisture, exposure duration) machined (the impact of factors: pressure and shearing force) represents ekstrudatsii technology.
ekstrudatsii principle is explained by the notion of. The verb "to extrude" comes from Latin and means "squeeze, push ". The material is crushed in the extruder channel, depending on the device type by means of one or two shafts of different configurations shnekopodobnyh (one- or twin shaft extruder) in translational motion and forced through small holes at the final channel. Thus a high pressure is created in the extruder channel as a function of device (possible to 100 have). Once the product leaves the extruder, there is a sudden pressure reduction and expansion of the extruded material. Due to the action of pressure and shear forces, -specific heat generated during the process and the effect of expansion of the material significantly changes the structure and characteristic achieved, visually definable texture.
High temperatures may occur during such processing, the material up to 200 ° C, although the duration is very short (few seconds). Because of this, such a process was ekstrudatsii abbreviation "HTST" (high temperature, short time).
The next difference is in the conditioning material prior to extrusion and introducing water under pressure. At the "wet ekstrudatsii" with the water flow and pressure through the air conditioner - Equipment for moisturizing (до 30% moisture in the material) obligatory drying mother after ekstrudatsii.
This processing step, very costly in energy, and hence the cost, still it was not widespread in the technology ekstrudatsii with production of raw materials for animal feeding.
Decisive known extrusion technology development has been the emergence of so-called technology opticon®. This technology allows to achieve targeting intensive changes similar structure as "wet" extrusion process described above. But thanks to the new concept is not needed energy-consuming drying of the processed material - in the end you just cool products. This technology allows to change the ratio of various grains in the end product and, in this way, save on storage extruded grains of different types separately in the feed mill or at the agricultural enterprise.
The destruction of the molecular structure
Для того, to understand, how the "disclosure of starch" in the grain, We need to look at its morphology and chemical structure. Grains contain depending on the type of 40 до 60 percent starch. Chemically pure starch can be divided on the amylose and amylopectin.
Amiloza (from 20 до 30% total starch in cereals) It composed of glucose molecules linked, that these compounds form long chains spiral winding.
Amilopektin (from 70 до 80% starch) - a branched polysaccharide, wherein the bound from 2 000 до 200 000 glucose molecules.
The ratio of amylose to amylopectin, chain length and degree of branching of the glucose chains significantly affect the technical properties of different types of cereal and the starch digestibility.
The endosperm starch grains is in the form of individual pellets, whose value ranges from 2 to 200μm. These starch grains are very easily distinguishable under the electron microscope (1000-fold increase) (cm. photo bottom left). They are fairly stable due to internal hydrogen bonds.
Branched molecular chains of amylopectin can produce these granules in place with unbranched amylose molecules semicrystalline and crystalline regions. These rigid structures are not split organic in water and natural, neizmelchonnoy form have considerable resistance to cleavage by enzymes.
Due to intense mechanical-hydrothermally treated cereal these structures change to the molecular level, starch "disclosed". The main effect - a significant increase of the surface area of starch granules and extensive cleavage of amylose and amylopectin. Changing the structure is also very well seen under the microscope. Typical starch grains after processing and are destroyed for the most part are fused into flat, resembling melted plastic habitats (cm. Photo below right).
Feeding pigs is very important, that along with the size and shape of the starch grains could vary their internal structure (crystal, amorphous, jelly-like area) and a view of grain - wheat, barley and maize. Here, everything has a greater influence processing of grain after harvest.
Since research in the field of cereal show, that in maize grains during drying changes the starch structure. corn, due to a much higher percentage of moisture in the grain at harvest compared to wheat and barley, It has to be dried more intensively. Starch because of this becomes even worse properties for digestion by the action of enzymes. it, along with other, is the cause, why raw cornstarch poorly digested by young piglets, compared, eg, with raw starch from wheat. Следовательно, technical "disclosure" plays an important role in particular to increase the digestibility of corn starch.
Stable digestion in the small intestine
The degree of modification of starch by hydrothermal treatment under pressure can be determined by the so-called amyloglucosidase (AMG-метод) laboratory LUFA Nord-West as the "degree of starch disclosure".
But, by LUFA information, to keep in mind, that certain indicators can be compared directly with each other only in the framework of the same kind of grain.
For quality assurance in the production of extruded cereal products were tested in accordance with the established standard for the degree of starch disclosure of AMG method. For use in the feeding of pigs types of grain, which lend themselves well to the disclosure, You should have a degree of opening 70%.
Cleavage rigid structures in starch granules by intense exposure to hydrothermal pressure provides a significant improvement in physically properties of the product to absorb water, and hence the ability to swell.
This can be seen on the corresponding pictures. The beaker was left to stir certain amount of raw cereal mixture with water. Unprocessed grain flours are very clearly visible. Compared with this the right glass of water was mixed with the same amount extruded cereal mixture with an appropriate amount of water. The extruded granule is completely absorbed the water, formed a homogeneous feed porridge.
For digestion it has significant advantages. Because of extruded feed grain better absorbs the gastric juice, homogeneously mixed and provides uniform prokislenie - is an important prerequisite for a stable digestion in the small intestine.
A feeding piglets rearing method with liquid extruded cereal positively ensure homogeneity aft porridge in pipelines and in the trough. Feed lot worse stratified and settles in a manger.
Extruded cereal may have a positive impact on the palatability of feed and increased feed consumption of pigs. Part of the disclosed starch already in the jaws of piglets cleaved saliva amylase to maltose (maltose sugar). Due to this there is a natural sweet taste, which has a positive effect on palatability and feed intake.
Furthermore, piglets with limited activity of amylase possible to reach increase starch digestibility in the small intestine. It is very quickly released glucose, which is absorbed directly through the intestinal wall and is available at the disposal of metabolism.
This is a significant improvement in the starch to glucose by the cleavage can be measured by a special laboratory method "in vitro". Так, eg, mixture of cereal, consisting in the 50% wheat, 25% corn and 25% barley was investigated before and after the above-described method ekstrudatsii opticon®. The extruded mixture after one hour is 90% starch were digested to glucose, in the non-extruded mixture - only 60% (cm. schedule "Extruded cereal split faster").
Since the residence time of the feed porridge in the small intestine is less than one hour, and then enters the ileum, only when fed a mixture of untreated grain compound feed for piglets large amount of overcooked starch misses the ileum. This leads to the potential for the development of pathogenic bacteria, such as E. coli, сальмонелла, but also of pathogenic organisms, specific to the ileum, Lawsonia intracellularis, since starch is a breeding ground for them. Intensive disclosure of cereal starch in the mixture and their partial introduction in feed for piglets can significantly influence the maintenance of a stable and healthy work ileum.
As already mentioned above, to optimize the digestion of starch in the small intestine along with the inclusion in the formulation extruded wheat must produce the same hydrothermal treatment under pressure introduced into the part of the formulation maize. But we need to remember about the extruded barley. Так, experiments, conducted in Spain and other European countries, show, when administered in feed for piglets extruded barley can be significantly improved weight gain as the, and feed conversion. The reason for this is, that can be observed intensive conditioning fiber fraction at a hydrothermal treatment under pressure except for the improved starch digestibility in the front part of the small intestine. Whereby these structural carbohydrates from barley are better broken down and its ability to bind water rises. This factor in the subsequent positive effect on manure consistency.
Productivity and health of piglets can significantly support through the use of breast-feed, taking into account the ability of animals to digest. "The disclosed cereal" occupy the central position, and is now not only the raw material for prestarters, but also increasingly and successfully used in feeding pigs rearing.
When the extruded cereals in feed for pigs must be considered not only one kind of grain, because the combination of extruded wheat, corn and barley provide additional benefits for digestion, productivity and health of piglets.
Due to technical installations available today can be extruded to produce a mixture of these three types of grain by hydrothermal "opening" pressure.
High levels of starch splitting (on average higher 70%) such mixtures and their proportional use in various kinds of animal feed for pigs - between 40 и 20% depending on the feed phase (cm. table "So confused with extruded grains") - the digestion of starch will be very targeted use in the front intestine. In addition to the related "productivity effect" due to better digestibility and increased feed consumption in the ileum and colon gets less undigested starch. This eliminates a major source of food for the pathogenic microflora, such as E.Coli, thereby further achieved by reducing the risk of diarrhea in piglets.