Abstract: For a long time, antibiotics have been used as a growth promoter in animal husbandry and have achieved good results. It has played a huge role in animal husbandry. The rise of the antibiotic industry has greatly promoted the progress of the aquaculture industry. However, a large number of practical facts show that a large number of long-term use of antibiotics will cause the resistance of harmful strains and drug residues of livestock products. In the case of animal products that have been eaten with antibiotic residues, physical health has been harmed, and allergic reactions have become more serious. The study of alternatives to antibiotics has become a hot topic in animal nutrition research. At present, in order to promote the growth of piglets, the same effect as the use of antibacterial agents cannot be obtained by only a single technique, feed additive, or feeding and management. Production experiments have shown that wanting to replace these antibacterial agents requires the use of a comprehensive set of strategies. The following summarizes several methods that do not contain antibiotics. In terms of production practices, several methods work synergistically with significant results.
Keywords: pig; feed additive; countermeasure
1. About improving animal health
1.1. Management of piglets
In addition to the selection of excellent crossbred piglets, piglets can adopt full-in, full-out feed management: pigs of similar weight are transferred to a pig house that has been cleaned and disinfected at the same time. All the pigs in the same pig house are listed in the same period and are in a new batch of pigs. Before coming in, all the pigsty in the pigsty should be emptied, cleaned and fumigated. Before the next batch of pigs are housed, the entire pig house must be completely and completely cleaned. The full-entry and full-out system of feeding and management can break the chain of disease transmission between the pigs; the virulence of any disease will not increase; pigs can be reduced. The occurrence of lung injury reduces the severity of damage; improves the average daily gain of the herd; reduces the number of days required to market weight; improves the feed conversion rate; compared to simply cleaning a single pigsty, when the entire pigsty is emptied, cleaning will be It is more efficient; it is more efficient to purchase piglets for the entire pig house than to purchase pigs for a single pigpen. The selection of feed should be based on the physiological characteristics of piglets, select easily digestible, high-nutrition feed, and at the same time can add piglet special health care products to the piglet feed. Specific use method: Add "Hua Cikang No.1" 2 in the feed after weaning. % feeding for 15 days, and then adding 2% of Hu Youkang 2 or 1% of Huanshang 1 to the feed and 1% of Huyoukang 2 to 70 pounds can effectively prevent Weaning stress and nutrient stress increase the feed conversion rate and increase piglet growth potential and disease resistance.
1.2. Improve sow health.
Sow health directly affects the growth of piglets.
It is very important to maintain the appropriate body condition for sows to be fat and thin. It is necessary to adjust the amount of feed during the sow's breeding cycle in order to ensure the larger birth weight of the piglet. Piglets with a higher birth weight mean stronger resistance to disease. In addition, those sows suffering from streptococcus, atrophic rhinitis, and asthma should be eliminated in time. At this stage, sows must be given high-nutrient feed, and at the same time, the sow-specific health product “No. 1†can be added to the feed. Specific use methods are as follows: 1. Reserve gilts, 6 months of age – before mating, in the feed Tim?% No.1, promotes the development of the sow's reproductive system, promotes multiple ovulation, multiple rows of viable eggs; 2, in the late pregnancy, 80-114 days add 1% No. 1 to the sow Adequate nutrition promotes the secretion of uterus milk, promotes the full development of piglets in the mother's body, promotes the development of immune organs, and improves the birth weight. (Practice has shown that the birth weight of piglets can reach 3 kg or more and the individual piglets are uniform. ); 3, breast-feeding needs a lot of nutrients, according to 2% in the diet to increase, promote the secretion of milk, improve the quality and quantity of colostrum, so that weaning pigs to 10 kg or more. At the same time promote sow uterine involution and promote normal estrus in the next stage of sows.
2. About weaning age
2.1. One view: Early weaning. The data recorded by {Pig Champ} shows that 75% of the pigs have been weaned or weaned earlier in 22 days and nearly 30% of the piglets have been weaned 16 days earlier. Previous point of view Early weaning control disease in piglets: There is no antibody in the blood of newly born piglets, and piglets receive immune antibodies (such as IgG, IgA, IgM) from colostrum. The content of antibodies in colostrum is higher at the beginning, but its content drops rapidly after 24 hours of delivery. At the time of 24-36 hours after birth, piglets can only absorb macromolecule immunoglobulin through the small intestine, after which the small intestine no longer absorbs. Immunoglobulins, so piglets are weaned early before getting antibodies.
2.2. Another view is that we must extend the age of weaning. The majority of European farmers adopt a weaning age of 24 to 28 days. According to the results of the relevant trials and studies, the maximum weaning age is better for animals that have not been fed with antibiotics. When it is strong, the feed intake will increase. On the other hand, as the age gets older, the immune system of the piglet will also improve.
The early weaning techniques of piglets emerged on the basis of more reasonable dietary formulation, and had a great effect on the use of sows. However, early weaning can also easily lead to diarrhea in piglets. Early weaning stress syndrome (PWSD) in piglets The main clinical manifestations are: feed intake of weaned piglets decreased by 15%-20%, growth stagnation (commonly known as milk aphids), feeding cycle extended more than 5 days; diarrhea, diarrhea rate of 30-100%, an average of 50%, serious The mortality rate reached 15%; concurrent edema disease; decreased resistance to disease. Early weaned piglets' stress and its syndrome is a major problem in swine production all over the world. It is commonly called “weaning offâ€, and clinically, the loss caused by weaning stress on piglets reaches 150 yuan per nest, which is caused annually in the pig industry in China. The economic loss is more than 6 billion yuan.
To solve the weaning stress, we can independently use Apron Health to raise piglets for health care. The specific method is as follows: Method 1: 10 piglets weighing 5-6 kg, and use 1 pack of “Acupuncture Kang 1†(or Hu Zikang Weanbao) (500 g) Weaning piglets with 25 kg of feed and mix for 15 days; weighing 9-10 kg, feeding with 2 bags of “Hua Cikang No. 1†(or Hu Tsai Kang Wean Po) and 50kg of weaned piglets, mix and feed for 15 days. . Method 2: If you have previously fed piglet pellets, you can use 90% piglet pellets + 8% wheat bran or corn flour + 2% Huzikang No. 1 (or Huzikang Wean Po) and feed for 15 days. Method 3: Formulate special feeds for weaned pigs and feed them for 15 days. Formula One: 60% corn, 6% wheat bran, 22% pudding, 10% hurry on the 10th, Huezang 1 (or Hu Tsai Kang Weanbao) 2%; Formulation 2: 64% corn, 22% soybean meal, 100-B12% faster, Aberdeen Kang 1-B2%. Can effectively solve weaning diarrhea and promote healthy growth of piglets.
3. About digestibility of nutrients
3.1. Effects of anti-nutritional factors
The feed often contains some anti-nutritional factors such as protein inhibitors, carbohydrate inhibitors, mineral element bioavailability inhibitors, antagonistic vitamins, and animal immune system factors. They interfere with the digestion, absorption and utilization of nutrients in feed and affect the digestibility of nutrients. For example: (1) Soybean cakes containing trypsin inhibitors and hemagglutinins can reduce trypsin and chymotrypsin activity, increase trypsin secretion, intestinal wall damage, increase endogenous protein secretion damage, and affect growth and death. (2) peanut cake containing aflatoxin, anti-trypsin factors, reducing the nutritional value of feed, affecting growth, leading to chronic poisoning of livestock and poultry. (3) Cottonseed cake contains free gossypol and cyclopropene fatty acid, which affects the effectiveness of lysine and mineral elements. (4) The rapeseed cake contains oxazolidine thiophene, isothiocyanate, which affects the use of iodine, palatability, and growth rate, causing goiter and damage, and ester tannins irritating the mucous membranes and causing diarrhea.
3.2. Utilization of synthetic amino acids
The utilization rate of nitrogen in livestock and poultry diets is usually only 30%-50%. To increase the nitrogen utilization rate, the balance of dietary amino acids must be increased; and when the amino acid content in the diet must account for 45%-55% of the total nitrogen content, Nitrogen has the highest utilization rate. According to statistics, the level of dietary crude protein calculated by the ideal model is one percentage point lower, and the release of excreta nitrogen is reduced by 10% to 12.5%. Adding synthetic amino acids to the diet can reduce the protein levels of growing pigs and finishing pigs from 21% to 14%, respectively, from 19% to 13%, resulting in a 40% reduction in urinary nitrogen excretion (P
3.3. Nutrition of the digestive tract
Nutrients that are not absorbed at the distal ileum of the digestive tract become a growing base for the growth of bacteria that grow in the large intestine. Huge bacterial vectors not only deplete animal nutrition, but also harbor a large number of pathogens such as E. coli, Salmonella and Clostridium, in addition, the unabsorbed nutrients eventually excrete fecal matter through the animal, which also imposes a heavy burden on the environment.
4. About feed intake
Feed intake plays a very important role in keeping piglets' internal organs healthy after weaning. Even if there is a short period of anorexia after weaning, the intestinal epithelium can be easily impregnated with antigenic proteins, such as antigen proteins in pods, and it is also easy for bacteria to adhere. Due to the hypersensitivity to antigenic proteins or bacterial endotoxin produced, piglets frequently suffer from diarrhea. At the same time, the decline in feed intake will also lead to a decline in pig production performance, a decline in the body's health status, and an extension of its slaughter period.
Therefore, it is critical to increase the intake of piglets by improving the palatability of the diet. In the piglet stage, the use of flavoring agents, a certain proportion of dairy products, and other good palatability animal raw materials will achieve good results.
5. About reducing dietary protein levels
The growth and proliferation of bacteria requires proteins. By reducing the protein in the diet and increasing its digestive capacity, bacterial proliferation can be significantly limited, and, most importantly, a well-balanced amino acid is needed.
Appropriately reducing dietary protein levels is effective in preventing diarrhea in piglets.
6. Application of Organic Acids
Most pathogenic bacteria do not have acid resistance, which means that acidification of the gastrointestinal tract with organic acids in the diet can actually prevent or transform the growth of bacteria. Other insoluble organic acids in the small intestine are used or killed by bacteria. The effect of mixing organic acids is greater than that of a single organic acid.
6.1. Types of Organic Acidifiers
At present, the acidifiers used at home and abroad can be divided into two categories: single acidifiers (including organic acidifiers and inorganic acidifiers) and composite acidifiers. Among them, organic acidifiers mainly include citric acid, fumaric acid, lactic acid, propionic acid, malic acid, formic acid, acetic acid, and their salts. The most widely used and effective ones are citric acid, fumaric acid, and calcium formate. Inorganic acidifiers include strong acids (such as hydrochloric acid and sulfuric acid) and weak acids (such as phosphoric acid). Their acidity is stronger than that of organic acidulants. Although the components are low, their use effects are poor. Compound acidifiers are compounded using several specific organic and inorganic acids. Experiments have shown that the application effect of the compound acidifier is greater than that of citric acid than fumarate. Compound acidifiers can significantly increase the daily gain and feed conversion rate of weaned piglets, and significantly promote the development of digestive organs in piglets. Most researchers believe that dietary acidification is effective during the first 1-2 weeks after early weaning (3-5 weeks of age weaning) in piglets, typically at 0.5%-3%, and in the United States at 2%-3. % is the best, Europe is the best 1.5%-2%.
6.2. Effect of Acidifier
The animal's stomach is in an acidic environment, in which the bacteria are mostly acid-producing bacteria and acid-fast bacteria. The young animals have weak secretion of gastric acid, making it easy for the external bacteria to survive and reproduce. The use of an acidifying agent can increase the acidity of gastric juice, promote the proliferation of acid-fast bacteria such as lactic acid bacteria, and maintain the status of dominant bacteria in the stomach, while E. coli and other foreign bacteria can not adapt to the acidic environment, and can't be colonized by lactic acid bacteria, etc. Survival can therefore reduce the incidence of pathological diarrhea in animals. Acidifiers can also help the body adjust the immune system response and enhance the animal's resistance to disease.
7. Application of plant extracts
Some herbal extracts have antibacterial and antiviral properties, but we know that flavorants have antibacterial and digestive properties, among which the most common extracts in commercial products are cinnamon, oregano, and cloves. It shows that the extracts and concentrates are very suitable for growing piglets.
The application of glycosides
The glycosaminoglycans are natural active substances extracted from camellia oleifera and tea seed cakes. They mainly contain oligosaccharides, triterpene saponins and organic acids. It is a relatively successful green feed additive and has been widely used in feed production.
8. Application of enzyme preparations
8.1. Kind of enzyme preparation
Since the establishment of the first enzyme preparation factory in Wuxi in 1965, after more than 30 years of hard work, our country's enzyme preparation products have continuously increased and the quality has been continuously improved. Alpha-amylase, β-amylase, protease, lipase have been developed so far. There are hundreds of products such as cellulase, pectinase, β-glucanase, mannase, and phytate.
8.2. Effect of enzyme preparation
Enzyme preparations can supplement the deficiency of endogenous enzyme activity. For young animals, there are disadvantages such as lack of digestive tract enzymes and low activity. Enzyme preparations can effectively compensate for the adverse effects of enzyme deficiency and low activity; enzyme preparations can also reduce or eliminate anti-nutritional factors in feed; enzyme preparations can also reduce the viscosity of digestive chyme, increase the effective absorption area of ​​the intestinal wall, and promote The contact and absorption rate of nutrients and digestive tract mucous membranes; enzyme preparations can also change the distribution of intestinal flora; researchers at home and abroad believe that the addition of enzyme preparations to feed can significantly improve the animals' daily weight gain, feed utilization and reduction. Diarrhea rates and mortality rates in young animals.
8.2.1. Application of phytase:
About 2/3 of the phosphorus in the plant feed is phytate phosphorus, which cannot be used by livestock. This not only results in the waste of phosphorus resources, but also causes most of the phytate phosphorus to be excreted from the excreta, causing serious environmental pollution. Phytic acid can also bind with many trace elements and hinder its absorption. The best way to address phosphorus contamination in feed is to add phytase to the feed. The main role of phytase is to replace or reduce the inorganic phosphorus originally added in compound feed by decomposing the abundant phytic acid and its complex in the feed into inorganic phosphorus and inositol which can be used by livestock and poultry. Improve the utilization rate of feed phosphorus, save a large amount of inorganic phosphorus resources, increase feed formulation space, and significantly reduce the discharge of phosphorus from livestock manure, reduce the pollution of phosphorus on the environment. On the other hand, phytase breaks down the phytate's complexing effect on phosphorus, calcium, protein, vitamins, trace elements and other nutrients by decomposing phytic acid, increases the potential nutritional value of feed, relatively reduces feed costs, and conserves feed. Resources.
8.2.2 Use of non-starch polysaccharide degrading enzymes:
At present, there is a lack of corn resources in China. The nutritional value of wheat is higher than that of corn, and its resources are abundant. It is the best substitute for corn. However, wheat seeds, especially the endosperm cell wall, contain more non-starch polysaccharides (NSP) and cannot be hydrolyzed by monogastric animal digestive enzymes. Furthermore, after it is partially dissolved in the digestive tract of animals, it forms viscous colloids with proteins and starch, making them less susceptible to contact with digestive juices. NSP will also combine with digestive enzymes to inhibit the penetration of digestive enzymes into the substrate, thereby reducing the digestibility and utilization of nutrients and reducing the energy value of the feed. In addition, the increase in undigested material will increase the amount of metabolic waste discharged, and the degree of pollution to the environment will also greatly increase. In order to increase the utilization of nutrients in wheat, the most effective method is to add exogenous non-starch polysaccharide degrading enzymes.
Recently, a new type of polysaccharide degrading enzyme was developed with NSP degrading enzyme as the main body, and a compound enzyme preparation of cellulase, amylase, protease and phytate. Its purpose is mainly to eliminate the anti-nutritional effect of NSP to the maximum extent, to fully release the nutrient available in the feed, to reduce the waste of feed nutrients, and to improve the environmental pollution of animal production. This is also one of the measures adopted by developed countries in order to fully tap feed resources and reduce the aquaculture industry's environmental pollution in the past decade. Numerous experiments have shown that adding non-starch polysaccharide enzymes can increase animal weight gain and feed utilization. It can increase the daily gain of piglets, feed utilization, and piglet mortality.
9. Application of probiotics
Providing beneficial live bacteria through feed is also a transformation strategy that does not use antibiotics.
9.1. Kinds of Prebiotics
Probiotics, also known as live bacteria, probiotics, and biocides, are a live microbial feed additive that has a beneficial effect on animals by improving the balance of the intestinal microflora (Fullar, 1989). In addition to Lactobacillus, Clostridium butyricum, and Streptococcus lactis, there are more than 40 species of microorganisms used, such as Aspergillus niger, Bacillus coagulans, Bacillus licheniformis, Bacillus subtilis, Bifidobacterium thermophilus, Saccharomyces cerevisiae, and Escherichia coli. .
9.2. The role of probiotics
In general, antibiotics regulate intestinal microbial communities by inhibiting or destroying microorganisms. Probiotics can prevent animal diseases by directly enhancing the animal's inhibitory effect on harmful microbial communities in the intestine, or indirectly by promoting non-specific immune functions, and indirectly promoting animal growth. Improve the role of feed conversion rate. In the digestive tract of the pig, not only beneficial bacteria but also harmful bacteria are parasitic. The harmful bacteria include Salmonella, Escherichia coli, Clostridium, Campylobacter. These harmful bacteria can not only harm the host animal by producing special diseases, but also can harm the health of the host animal by competing for necessary nutrients, thereby reducing the production performance of the animal; on the contrary, some bacteria such as lactic acid bacteria and bacteria producing B-complex vitamins The host has a favorable influence. The ideal microflora in the digestive tract includes a considerable number of beneficial bacteria. However, due to physiological factors and its environmental stress, imbalance of intestinal microflora can be caused, resulting in the proliferation of pathogenic microorganisms, eventually leading to animal diseases and decreased production performance. Probiotics increase the number of ideal microflora in the gut microbiota, making the balance of the gut microbiota toward more reasonable microflora. It has also been reported that prebiotics may produce antibiotic substances and may also stimulate the early development of the immune system in pigs. Numerous experiments have demonstrated that probiotics have the effects of increasing weight gain, improving feed conversion efficiency, promoting immune function of livestock and poultry, reducing mortality, and improving the environment. Such as improving the survival rate of broilers, daily gain and feed efficiency, improve the survival rate and growth rate of piglets, and effectively prevent diarrhea in piglets have a good effect.
10. Application of oligosaccharides
Oligosaccharides are not digested by digestive enzymes in the animal's intestine and can only be selectively used by microorganisms such as Lactobacillus and Bifidobacterium that are beneficial to the body, and cannot be used by microorganisms such as Salmonella and Escherichia coli that are harmful to the body. After the oligosaccharides are used by the beneficial bacteria, the beneficial bacteria such as Lactobacillus and Bifidobacterium are proliferated in a large scale; the proliferation of beneficial bacteria produces lactic acid, butyric acid, acetic acid and propionic acid, which lowers the pH of the intestinal tract, thereby making The propagation of acid-resistant harmful bacteria is inhibited, thereby improving the intestinal environment and the proliferation of beneficial bacteria in the intestine. Bifidobacteria have a strong immune effect on the animal body. The bifidobacteria cell wall contains a large number of peptidoglycans and teichoic acids. It has strong biological activity and can activate the activity of peritoneal macrophages, NK cells, and lymphocyte factor-killing cells. Bifidobacteria can also be used as an immune agent. Adjuvants, stimulate the body to produce antibodies and slow the release of antigens, prolong the time of the antigen; Bifidobacterium can also be combined with cancer cells, has anti-tumor effect, eliminate free radicals and increase SOD activity. The above mechanism has made the body's immunity significantly improved, thereby improving the health of the herd. Oligosaccharides also prevent the colonization of pathogenic bacteria in the intestine and promote its excretion with the feces. The results of the study showed that intestinal pathogens must first be bound to the intestinal mucosa to colonize and multiply in the gastrointestinal tract to cause disease in animals. This binding is achieved by the binding of lectin on the surface of the bacteria to the sugar molecules specific for the animal's intestinal epithelial cells. It has been proved that most of the intestinal pathogenic bacteria have lectins that specifically bind to oligosaccharides, so that the pathogens cannot bind to intestinal epithelial cells and are eliminated together with the feces, so that the body's immunity is enhanced and the body's health is improved. . Oligosaccharides also stimulate the immune response, improve the body's immune system and improve the health of the body. Oligosaccharides can bind to the surface of certain toxins, viruses and eukaryotic cells and serve as an adjuvant for foreign antigens, which can slow the absorption of antigens and increase the titer of antigens. LeGarrec (1986) has reported that oligosaccharides can enhance cellular and humoral immunity as an immune adjuvant. Spring et al. (1998) deeply studied the effect of oligosaccharides on the immune ability of piglets. Oligosaccharides can significantly increase the serum Ig depth and the number of B lymphocytes in pigs and improve the humoral immunity of piglets; oligosaccharides can also increase leukocytes. Interleukin (IL-2) DE concentration, IL-2 can make T cells proliferation and differentiation, improve the immune function of piglets. In addition, oligosaccharides also have antigenic properties, can generate specific immune responses, and enhance the body's immune system.
In recent years, many studies have shown that adding appropriate amounts of oligosaccharides to animals, especially young animals, can promote animal growth, reduce the occurrence of diseases, and improve feed utilization (Fukuyasu and Oshita, 1988; Bastein, 1990; Bolduan, 1993 Sisak, 1994). Studies by Hidaka (1987), Fukuyasu (1987), and Stuttton (1998) suggest that oligosaccharides such as fructooligosaccharides have the effect of promoting animal growth and preventing disease. Morishita (1982, 1992), Koayshi (1990), and Bolduan (1997) pointed out that oligosaccharides promote the proliferation of digestive tracts such as Lactobacilli, Bifidobacteria, Streptococcus, and other beneficial bacteria, and thus increase the fatty acids in the intestinal contents. , Lower PH value. Fukuyasu (1987) reported that adding 0.25% of oligosaccharides to piglets' diets increased the concentrations of bifidobacteria and lactobacilli in the feces of piglets. In the trial of Stutton et al. (1994), the addition of 1% galactan can effectively inhibit the proliferation of ileal E. coli in piglets, while Lactobacillus is significantly higher than the control group. After 2 days of weaning, 1% galactan is added, and the ileal lactic acid bacteria are added. Higher than the control group, the difference reached a significant level on the fourth day (P
11. Application of immune stimulants
The hens are subjected to a certain kind of E. coli hyperimmunization, and the eggs are subjected to a special spray drying process to make a sprayed egg powder and feed the pigs so that the pigs are immunized. It has been shown that this can effectively reduce the incidence of diarrhoea and, in particular, some other supplementary measures. Pigs suffering from visceral edema disease benefit greatly from this nutritional regulation.
12. Application of plasma proteins and trace elements
12.1 Application of Plasma Protein Powder
Plasma protein powder is prepared by separating from pig blood collected in abattoirs and disinfecting and destroying microorganisms. It is a rich source of immunoglobulins, increases feed intake and reduces diarrhea, and provides stable immunoglobulins in the stomach and small intestine. source.
12.2 Application of Trace Elements
Animal tissue contains about 45 kinds of mineral elements, among which trace elements related to animal nutrition mainly include iron, copper, manganese, zinc, selenium, iodine, cobalt, molybdenum, fluorine, tin, nickel, silicon, arsenic, chromium, and vanadium.
For example, chromium can be used as an active ingredient of glucose tolerance factor, and it can cooperate with insulin in carbohydrate, fat, protein and nucleic acid metabolism. And the need for chromium to exercise under stress, disease (diabetes, hypoglycemia, atherosclerotic heart disease), increased under some physiological conditions (pregnancy, secret milk), transportation, heat stress, and nutritional deficiencies ( Zhang Minhong, 1996; Gregory et al., 1999. In addition to yeast chromium, other types of organic chromium include chromium nicotinate chromium picoline (chromium picolinate, picolinium chloride).
13. Application of Health Pig Technology
Animals live in the natural environment and are constantly attacked by various pathogenic factors. At the same time, the animal's body also resists and attacks the motivational body to make it in a relatively balanced state. Therefore, animals are absolutely healthy and in a disease state. When the attacking power of the pathogenic factor is not changed, the sub-health state is transformed into a disease state. Therefore, the general principle of animal health care is to uphold evils. Uprightness is to maintain or enhance the body's own special and non-specific gender resistance to disease. We are also called active health care. Evil and evil is to reduce or eliminate all kinds of pathogenic factors. We also call it passive health care, such as improving sanitation, disinfection, keeping ventilation in piggery, supplying sufficient drinking water, and adding appropriate drugs.
Therefore, the health care of pigs is to reduce or eliminate all kinds of pathogenic factors, maintain and improve the animal's own special and non-specific disease resistance in order to achieve health and disease prevention and increase efficiency and new methods of raising pigs.
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