Today, when fats and oils are widely used in feed, it has become a common phenomenon that feed oxidative rancidity leads to formula distortion. Especially under high-temperature and high-humidity conditions, oils and fats oxidize and deteriorate quickly. Sometimes they will deteriorate and give off a foul smell after a few days of production and storage. The nutritional value of the feed is reduced, and the palatability is extremely poor. Similarly, vitamins (such as VA, VC, VK, etc.), fish meal, meat meal, blood meal, feather meal, etc. in feed are highly oxidizable substances. In addition, since the development of the trace element feed industry, a large number of new active substances have emerged, such as probiotics, plant essential oils, enzyme preparations, etc. These feed additives tend to decompose and lose nutritional value through oxidation.
The essence of feed oxidative deterioration is the oxidative rancidity of substances containing unsaturated bonds (such as fats and fat-soluble vitamins). Oxidative rancidity mainly occurs on the carbon atoms adjacent to the unsaturated double bond. After oxidation, hydroperoxides are generated, and short-chain products (free radicals) are generated. The free radicals then attack other molecules containing unsaturated double bonds, and at the same time produce more If there are many free radicals in the process, if there are metal ions, the oxidation rate of feed will be accelerated. Therefore, trace elements in the feed have a great influence on the oxidation of feed nutrients. This article mainly reviews the effects of different dosage forms and deep processing forms of trace elements on the oxidation of feed ingredients, as well as the corresponding solutions, in order to provide evidence and reference for avoiding the damage of trace elements to the active ingredients of feed and improving feed quality in the future.
1. Oxidation of trace elements on oil
Sources of trace elements in feed include trace elements contained in animal and plant raw materials and trace elements added to meet the physiological needs of livestock and poultry. During the storage of oil, the trace amount of free fatty acid contained in the oil will react with the metal to form a small amount of fatty acid salt, which will enter the oil and feed in the form of ions. The order of its catalytic activity is Cu>Fe=Mn>Cr>Zn. Especially in livestock and poultry feeds that have special requirements for trace elements, such as high copper and high zinc in suckling piglets, the damage of trace elements to the effectiveness of oil is more obvious.
2. Destruction of vitamins by trace elements
The structure of most vitamins contains unsaturated double bonds and free hydroxyl groups, similar to oil oxidation, the instability increases under the action of trace elements, which is also the reason why trace elements cause the loss of vitamin activity. When there is moisture and fatty acids, it will speed up the reaction. Different forms of trace elements have great differences in the degree of influence on the stability of vitamins, especially sulfate compounds have a greater impact on vitamins.
In addition, the content of crystal water in trace elements will also affect the stability of vitamins. Studies have shown that the higher the crystal water content in ferrous sulfate, the greater the loss of vitamin A. The reason is not only the single effect of iron ions or water, but the interaction effect of the two. The combination of choline chloride in the premix and the crystal water in ferrous sulfate causes the oxidation of ferrous sulfate to turn brown. If the concentration of choline chloride in the premix exceeds 20%, the alkaline carrier and sodium chloride will accelerate this process. A reaction will promote the agglomeration and heat generation of the premix.
3. Effect of trace elements on active substances in other feeds
With the development of additive technology, a large number of new active substances have appeared in the feed industry, such as plant essential oils, enzyme preparations, probiotics, etc. Especially in the context of the national promotion of antibiotic-free feed, these substances, as new feed additives, have a very good effect on improving the efficiency of livestock and poultry breeding, improving disease resistance, and improving the sanitation of the breeding environment. However, in actual production, the effectiveness of these active substances will be affected by minerals or trace elements. Liu Laiting et al. (2001) reported that when probiotics containing lactic acid bacteria and bacillus were added to pig premixes containing high copper, the effective number of viable lactic acid bacteria decreased rapidly after 5 days of storage, and no trace was detected after 15 days of storage. The viable count of lactic acid bacteria was decreased, but Bacillus was less affected. Trace elements copper and zinc have a greater impact on probiotics, which is related to the antibacterial effect of high copper (copper sulfate) and high zinc (zinc oxide). When selecting probiotics in feed, we should not only consider the influence of feed processing conditions on probiotics, but also the influence of trace elements on probiotics (storage). Probiotics with strong stress resistance or special processing should be selected.
The influence of trace elements on plant essential oils is different from that of microorganisms or probiotics, because the components of plant essential oils are relatively complex, but the main types of compounds include terpenes, alcohols, aldehydes, ketones, phenols and lactones. They also have double bonds, so they are vulnerable to oxidation loss caused by metal ions or trace elements.
4. Effects of different dosage forms or deep processing forms of trace elements on feed nutrients
In order to reduce the oxidative damage of trace elements and trace elements to other nutrients and active substances in the feed, a lot of research has been done on the processing methods of trace elements at home and abroad. By coating the trace elements with suitable coating materials, it can overcome There are many deficiencies in the trace elements of inorganic salts, and the utilization efficiency of trace elements is improved. Studies have shown that effective coating treatment of ferrous sulfate can avoid product discoloration, reduce the oxidation rate of feed oil, improve feed quality and extend shelf life.
Under different external storage conditions, the coating treatment of compound trace elements can effectively reduce the oxidative loss of vitamin A caused by trace elements. At the same time, the study showed that there was a 50% difference in the loss of vitamin A (12.27% VS 24.57%) after the coating treatment of trace elements and storage at 30°C and 40°C for 24 days. Even the coating of trace elements will oxidize the active substances in the feed, especially under the addition of high temperature and high humidity.
In addition to the coating technology, organic trace elements can also reduce the loss of easily oxidized substances in the feed. Organic trace elements refer to complexes or chelates formed by the combination of metal elements and organic complexes through covalent bonds or ionic bonds, which have the advantages of high absorption, low emission, growth promotion, and immune enhancement. In studies comparing the effects of different formulations of trace elements on vitamin availability, organic trace elements are less destructive to vitamins than oxides, carbonates, sulfates, and free gold.
From the above results, organic trace elements can also effectively reduce the damage to nutrients in the feed. If the organic trace elements are coated, will it have a good effect? The use of organic trace elements minimizes metal ions and reduces the oxidation reaction between nutrients; at the same time, the organic trace elements are further processed through advanced coating equipment to reduce dust and contact surfaces. The results of the study on the effect of coated organic trace elements (i.e. fully chelated coated minerals) on the effectiveness of vitamins showed that compared with the control group, the fully chelated coated minerals group can effectively reduce the damage of trace elements to vitamins (Table 1 , Gironda Group, 2019). Fully chelated coated minerals greatly increase the protective effect on other nutrients in the feed. In actual production, due to the characteristics of low addition and high absorption of organic trace elements, the added amount of fully chelated coated minerals is lower than that of general trace elements. , so further reducing the oxidative damage to other nutrients.
Fully chelated ore-coated ore reduces the damage and loss of active substances in feed, which is actually a manifestation of cost savings for feed manufacturers. In the storage test of 1% compound premix for suckling piglets, we found that fully chelated coated minerals can reduce the loss of compound multidimensional by 15% (3kg), and reduce the loss of 180 yuan, while reducing the loss of vitamin C by 30% (0.9kg ), less loss of 25 yuan and less loss, a total of 205 yuan can be saved. In actual production and application, the empirical data of fully chelated coated ore in Jilongda shows that fully chelated coated ore can improve breeding efficiency and increase breeding income. For example, if laying hens use fully chelated coated minerals (laying poultry golden egg granule k), the broken egg rate is reduced by 0.5%, cracked eggs are reduced by 0.7%, sandy shell eggs are reduced by 1.98% (late stage), and faded eggs are reduced by 4.8% % (later stage), input-output ≈1:3.7; sows use fully chelated coated minerals (Shengzhubao k), shorten the sows’ weaning to estrus by 0.5-0.8 days, increase the farrowing rate by 4.8%, and increase the annual litter Count 0.5-1.1 heads, and increase the birth weight by 70-90g/head.
In addition to the above characteristics, fully chelated coated ore has other advantages:
(1) Compared with other organic minerals with unclear composition, specific amino acid chelate minerals have detectable components, clear chemical structure, chelation rate and molar ratio and other indicators;
(2) Compared with inorganic minerals, specific amino acid chelated minerals have good stability, low irritation and high utilization rate, and can be supplemented quickly and intensively when needed;
(3) Chelate ore + coating double upgrading process, less damage to other feed nutrients, functional substances and antibiotic ingredients, equivalent to "double insurance";
(4) Released in a specific part of the digestive tract to improve utilization and reduce intestinal irritation;
(5) The double upgrading process of chelation and coating for micro-minerals has realized multi-channel and step-by-step absorption, greatly reducing the antagonism between trace elements and improving the utilization rate;
(6) As far as the powder is concerned, the dust is low, and the sharp-billed poultry likes to eat.
Trace elements are one of the important "behind the scenes" that cause the oxidative loss of feed ingredients and the distortion of formula. Coating trace elements can effectively reduce the damage to feed ingredients to a certain extent; on this basis, the organic trace elements The coating treatment of elements, that is, the full chelation coating technology, can not only give full play to the advantages of high biological availability of organic trace elements, but also minimize the damage to feed oil and other active ingredients, and can achieve feed nutrition. The double guarantee and the double value-added effect of breeding benefits.
Sichuan Chelota Biotechnology Group Co., Ltd. provides you with organic trace elements, organic chelated microminerals, and inorganic trace elements. It is a large trace element fertilizer manufacturer in the country. Welcome to visit the factory.