What are the feed additives that promote growth in pig farms?
Now is a new era of pig raising, an era of high investment in high technology and focus on cost and efficiency. Today's pig industry requires a larger pattern and overall thinking, and requires high-quality industry talents and management talents. After several years of circovirus disease, foot-and-mouth disease, and highly pathogenic blue-ear disease, as well as the adjustment of national policies, rural family farming and small and medium-sized pig farms have begun to gradually withdraw from the breeding market. With the investment of capital, feed enterprises develop large-scale breeding through one-stop, breeding cooperatives develop feed factories upstream, the Internet and the entry of funds from other industries such as finance and energy mining have brought the rapid development of breeding companies. Coupled with the use and management of vaccines and the advancement of concepts for many years, the occurrence of large-scale severe infectious diseases has basically been eliminated. After ensuring the stable production of pig farms, we pay more attention to how to reduce the feed-to-meat ratio, how to improve meat quality, and let pigs spend less time on slaughtering. For pig farmers, the importance of promoting growth is more prominent. This article briefly introduces several growth-promoting feed additives and their advantages and disadvantages for reference.
The mechanism of action of antibiotics to promote the growth of pigs is mainly its bactericidal and bacteriostatic effects, which can prevent the reproduction of harmful microorganisms in the gastrointestinal tract and the production of toxins, prevent the occurrence of diseases and reduce the thickness of the intestinal wall, which is conducive to nutrient absorption, thereby improving the feed quality. utilization, and promote the growth of pigs. However, with the emergence of drug resistance, people have gradually discovered its harm to human beings. Relevant organizations in various countries have promulgated prohibition policies on the prohibition of antibiotics used in feed and some functions. Feed mills and breeding companies have begun to seek other safer effective way.
2 Traditional Chinese medicine additives and extracts
The role of traditional Chinese medicine additives is mainly manifested in disease prevention and health care, improving animal production performance, improving animal product quality and improving feed quality. The use of Chinese herbal medicines has a long history, but there are many kinds, different places of origin and medicinal parts and differences in preparation methods also lead to different efficacy. Modern scientific research shows that polysaccharides, total flavonoids, alkaloids, glycosides, volatile oils, amino acids, etc. in the unique medicinal components of traditional Chinese medicine can achieve the best efficacy through extraction and purification processes. The effect is different. Effective and ineffective are not absolute. Some ingredients that were originally considered ineffective became active ingredients because they were found to have biological activity, while some effective ingredients became ineffective in other Chinese medicines.
3 Probiotics and Derivatives
Several functions sometimes synergize and promote each other.
Prebiotics, such as dietary fiber and oligo-oligosaccharides, cannot be absorbed by the body, but can provide nutrients to the intestinal beneficial flora and indirectly promote the growth and reproduction of probiotics.
Probiotics, such as Bacillus and other powerful bacteria, directly participate in the balance of the flora, and compete for nutrition and living space to improve intestinal health and promote growth.
The metabolites of probiotics, such as the acids and enzymes produced, have functions such as improving blood pressure and improving immunity. There are also many kinds of metabolites. Strictly speaking, quite a few antibiotics and enzyme preparations are produced by bacterial fermentation.
4 nutritional supplements
It can be divided into the following categories.
The first category is enzyme preparations. Such as proteases, cellulases, amylases, complex enzymes, etc.
The second category is organic acids and their salts. Such as citric acid, fumaric acid, formic acid, lactic acid, acetic acid, etc.
The third category, functional amino acids.
The fourth category is vitamin supplementation. For example, in the feeding of high-producing sows, the need for multi-dimensional in the diet is increased by 10%.
The fifth category is the supplement of trace elements. Especially after the promulgation and implementation of new relevant laws and regulations, there are stricter regulations on the content of copper, iron, zinc, arsenic in feed, inorganic trace elements are gradually replaced by organic trace elements, yeast selenium, amino acids chelate metal ions, etc. The mechanism is clear and the addition amount is also smaller.
5 Application of modern biotechnology and genetic engineering
Including steroids, beta sympathetic agents, adipocyte hormones, growth hormones, etc.
Since Szabo reported in 1981 that cysteamine can reduce somatostatin (SS) and increase the level of growth hormone (GH) in animals, many scholars at home and abroad have done a lot of research on its mechanism of action and application effect.
Cysteamine (CS) is a hormone-regulated growth-promoting additive, chemical name is β-mercaptoethylamine, white crystal, alkaline. It can be regarded as the decarboxylation product of cysteine. The molecular structural formula is: (C2H6NS)2Zn. Molecular weight 77.15. Animal growth hormone is the most powerful endocrine hormone that promotes animal growth. GH is controlled by both positive and negative growth hormone-releasing hormone (GHRF) and somatostatin secreted by the hypothalamus. According to research, the active sulfhydryl group of cysteamine can chemically modify the disulfide bond of somatostatin, changing its molecular structure and physiological activity, thereby reducing the level of somatostatin, resulting in an increase in the level of growth hormone and promoting animal growth. At the same time, cysteamine can reduce the decomposition of dopamine in animals, and promote the synthesis and secretion of growth hormone in the hypothalamus, which is also one of the growth-promoting pathways.
Cysteamine is a simple chemical substance with low production cost, which can be ingested with the feed and absorbed through the digestive tract, and is suitable for use as a feed additive. Growth hormone and growth hormone-releasing hormone are protein and peptide endocrine hormones, which are expensive to produce and can only be used by injection. Unlike growth hormone, cysteamine is generally effective for poultry, pigs and ruminants regardless of animal species. However, cysteamine has great defects, has a strong odor and tastes bitter, so it is not suitable to be added directly to animal feed. At the same time, cysteamine hydrochloride is very easy to oxidize and absorb moisture, resulting in the rapid oxidation of cysteamine hydrochloride in the process of granulation, coating process and product placement, which affects the use effect of the product. Therefore, to apply cysteamine in feed production, the following major problems must be solved:
First, to maintain the stability of cysteamine during storage and feed processing;
Second, maintain the stability and physiological activity of cysteamine in the body;
Third, maintain the physiological homeostasis of the body, and no negative feedback such as growth hormone occurs;
Fourth, it is easy to deliquescence and not resistant to high temperature. The melting point of its hydrochloride is 66°C to 70°C, which has poor palatability and is easily oxidized in neutral and alkaline environments.
Functional amino acids such as cysteamine, leucine and taurine can regulate nitrogen metabolism technology (Yinyulong), which can improve the body shape and meat quality of pigs at a low protein level, avoiding the use of clenbuterol. The amino acid metal chelate technology can safely utilize trace elements without significant differences in the nutrition and growth effects of pigs. Using cysteamine hydrochloride and zinc sulfate heptahydrate as raw materials, the reaction conditions were optimized by orthogonal experiment to synthesize stable cysteamine-zinc complex. The cysteamine chelated zinc has chemically modified the sulfhydryl group in cysteamine, which improves the stability of cysteamine, reduces its reducibility, and reduces the reaction with metal elements in the feed. The test results show that adding cysteamine The feed intake and weight gain of pigs in the chelated zinc group were improved, the feed-to-weight ratio was reduced, and the defects in the use of cysteamine and its hydrochloride were avoided. The main advantages are as follows:
First, in the process of feed processing, cysteamine zinc does not undergo oxidative decomposition due to high temperature (120°C);
Second, in a strong acidic environment, cysteamine zinc is decomposed to release cysteamine, and as the acidity weakens, cysteamine zinc is partially decomposed;
Third, the biological activity study of zinc cysteamine found that the release rate of cysteamine was greater than 75% within half an hour in the simulated gastrointestinal fluid, (C2H6NS)2Zn+2H+→2C2H7NS+Zn2+, in the In the acidic environment of animals, zinc cysteamine is decomposed into two cysteamines and one zinc ion.
In the finishing pig diet, the weight gain of the group supplemented with 200 g of zinc cysteamine per ton increased by 4.2%, the feed consumed per kg of weight gain decreased by 6.7%, and the diarrhea rate decreased by 44.5% and 49.8%, respectively. A large number of experiments have proved that the addition of cysteamine zinc can effectively improve the daily weight gain of growing and finishing pigs and increase the lean meat rate.