Oxytetracycline is one of the commonly used veterinary drugs, which is of great significance in livestock and poultry production, and has a good preventive effect on livestock and poultry diseases.

As the first-generation natural antibiotic, oxytetracycline is currently mainly used in animal husbandry and synthetic doxycycline. The application of oxytetracycline in animal husbandry is mainly used as veterinary antibiotics and feed additives. The former is commonly used to treat respiratory and digestive tract infections in livestock and poultry. Its preparation forms include oxytetracycline injection and oxytetracycline hydrochloride injection, etc. The main therapeutic functions include: paratyphoid fever, swine asthma, dysentery of young birds, and chlamydia in mammals such as pigs; the latter can be used in animal husbandry to prevent diseases and promote animal growth. In some countries, oxytetracycline is considered to be a growth-promoting factor, and its preparation forms include oxytetracycline base and oxytetracycline salt, the latter of which are oxytetracycline calcium salt and oxytetracycline hydrochloride.

Oxytetracycline tablets

Figure 1 shows oxytetracycline tablets

Below, let's learn more about oxytetracycline together:

【Overview】

Oxytetracycline (Oxytetracycline, OTC), also known as geomycin, oxytetracycline, 5-hydroxytetracycline, is a kind of tetracycline antibiotics, is a broad-spectrum antibacterial drug, it is not only against Gram-positive bacteria, such as staphylococcus, hemolytic Streptococcus, Clostridium tetani and Clostridium are effective against Escherichia coli, Pasteurella, Klebsiella, Clostridium perfringens, Bacillus pseudomallei, Haemophilus, Salmonella and Brucella Gram-negative bacteria such as bacteria are effective, and can also inhibit pathogenic microorganisms such as rickettsia, mycoplasma, chlamydia, spirochetes, actinomycetes and certain protozoa. Therefore, they are widely used as antibacterial agents and growth promoters in animal husbandry. industry.

The antibacterial mechanism of oxytetracycline is mainly through binding to the 30S ribosomal subunit of bacteria, interfering with bacterial protein synthesis and hindering the binding of aminoacyl-tRNA and ribosomes [11], thereby achieving the effect of inhibiting bacterial reproduction. As a traditional antibiotic, oxytetracycline is favored by farmers because of its accurate curative effect and low price. It has good effects on disease prevention and growth promotion. At present, in our country, it is mainly used as medicine and feed additives for livestock and poultry, and it is also used more in the aquaculture industry. Its effect on controlling amoebic enteritis and intestinal infection is relatively good. In order to facilitate administration, oxytetracycline is often processed into a safe, stable and easy-to-use form, which mainly includes oxytetracycline tablets, oxytetracycline base, oxytetracycline salt, long-acting oxytetracycline, etc. As a feed additive, oxytetracycline is usually used in the form of oxytetracycline base, oxytetracycline calcium salt, and oxytetracycline hydrochloride.

【Formulations】

1. Oxytetracycline base Oxytetracycline base is extracted from the culture broth of Streptomyces rimosus. Oxytetracycline is an oxytetracycline cell cultured by fermentation, and it prevents and cures diseases through its own metabolic mechanism. At present, the domestic oxytetracycline extraction process is to use oxalic acid as an acidifier to adjust pH, use yellow blood salt-zinc sulfate as a purifier to synergistically remove protein and other polymer impurities, and then use 122 resin to decolorize the oxytetracycline filtrate, and finally adjust the pH It crystallizes to about 4.8 to obtain the oxytetracycline base product. Oxytetracycline alkali is cheap and convenient to use, and is very suitable for use in grassroots farms; its main disadvantage is that some of the oxytetracycline will be absorbed by the gastrointestinal tract, resulting in residues in livestock and poultry products, resulting in drug resistance. In addition, oxytetracycline in the intestine can also bind calcium in the animal's body, resulting in calcium deficiency in the animal's body.

2. Oxytetracycline hydrochloride Oxytetracycline hydrochloride is obtained through a series of procedures with oxytetracycline base as the starting material; it is easily soluble in water and can be made into soluble powder and injection forms. The quality standard of oxytetracycline hydrochloride soluble powder is included in the "Compilation of National Standards for Veterinary Drugs: National Standards for Raising Local Standards for Veterinary Drugs". It is commonly used in veterinary clinics to treat sensitive Gram-positive bacteria, negative bacteria and mycoplasma infections. Its disadvantage is that it is easily absorbed by the gastrointestinal tract, its absorption effect is significantly higher than that of oxytetracycline base, and its toxicity is also greater than that of oxytetracycline base. It has more residues in livestock and poultry products and can produce drug resistance. Long-term use is a threat The health of the eating crowd.

3. Oxytetracycline calcium Oxytetracycline is produced and used in the form of calcium salt, which can improve the stability of oxytetracycline and reduce the absorption of oxytetracycline in the gastrointestinal tract, thereby reducing the residue of oxytetracycline in livestock and poultry products. Oxytetracycline calcium for feed is the addition of a certain amount of adsorbent calcium carbonate to the oxytetracycline fermentation broth to combine the free alkali of oxytetracycline with calcium ions to form a complex salt, which is filtered, dried and ground. The crude product of oxytetracycline calcium salt made by sieving and other steps. Because it is a crude product of an unpurified antibiotic, in addition to a certain amount of effective oxytetracycline calcium salt, it also contains a large amount of mycelium of oxytetracycline fermentation broth and metabolic residues during fermentation. Therefore, the product contains a certain amount of nutrients, such as crude protein, crude fat, amino acids, trace elements, etc. These substances have a certain effect on preventing diseases and promoting the growth of livestock and poultry.

【harm】

1. The influence of oxytetracycline on plants. Soil characteristics and plant types can determine the degree of influence of oxytetracycline on plants. Oxytetracycline does not directly produce toxic effects on plants in freshwater. However, the higher concentration of oxytetracycline can easily color the water body, thereby causing the photosynthesis of aquatic plants not to be carried out, and indirectly harming plant growth. As the concentration of oxytetracycline increases, the greater the impact on the lettuce, only 1mg/L of oxytetracycline can threaten the roots of the lettuce. When the concentration of oxytetracycline is greater than 5mg/L, it will affect the leaves and leaves of the lettuce. Root growth will have an inhibitory effect.

2. The impact of oxytetracycline on organisms. Various microorganisms constitute the soil ecosystem. Very low concentrations of antibiotics can affect the growth of microorganisms. Due to the large-scale use of oxytetracycline, the balance of microbial communities is unbalanced and damages the original soil. Microorganisms, but not every kind of microorganisms are the same, but they will definitely affect soil fertility. The order of the effect of oxytetracycline on environmental microorganisms from low to high is generally: fungi

3. The production and spread of drug-resistant bacteria. Under natural circumstances, the concentration of antibiotics in the environment can basically remain unchanged, but due to the flood of antibiotics, the residues of various metal ions and the coexistence of various pollutants in the natural environment, Drug-resistant bacteria were born. Among the many animal manures, only pig manure can more intuitively explore the factors that affect the abundance of tetracycline resistance genes in the soil environment. The resistance of cultivable microorganisms in soil to tetracycline after the application of pig manure is significantly increased. The widespread use of antibiotics has led to a rapid increase in resistance genes in the soil. As the concentration of oxytetracycline increases, the number of antibiotic-resistant pathogens that directly affect humans has increased significantly. The transmission media of drug-resistant bacteria widely include air transmission, in the soil of animals and plants, in the ocean, including large lakes and groundwater, which threaten human health.

【Precautions】

1. The harm of oxytetracycline taken by herbivorous livestock

(1) Cause changes in the function and shape of the digestive tract. Adult herbivorous livestock feed on forages. In addition to digesting forages, they also rely on a large number of microorganisms in the stomach and intestines. After oral administration of oxytetracycline, the microorganisms in the gastrointestinal tract are inhibited or killed, which disrupts the normal digestion process and causes digestive disorders. For example, after oral administration of oxytetracycline in sheep, it can cause anorexia, abdominal distension, foregastric relaxation and diarrhea; after oral administration of oxytetracycline in rabbits, it can cause intestinal mucosal necrosis, shedding of intestinal epithelial cells, intestinal submucosal congestion and edema.

(2) To cause "double infection" in livestock, causing poisoning and death. There are a certain number of bacteria in animal muscles, including non-pathogenic bacteria, pathogenic bacteria and conditional pathogenic bacteria. Due to the mutual restraint between the flora, under normal circumstances, they can coexist peacefully and maintain a balanced symbiosis state. After oral administration of oxytetracycline, the sensitive flora is inhibited, and the drug-resistant flora takes the opportunity to overproduce because it loses control, causing serious harm to the body, which is called "double infection". It can cause enteritis, pneumonia, urinary tract infections and sepsis. In addition, there are many bacteria in the intestines, which have the ability to synthesize B vitamins and vitamin K, which can supply vitamins to the body, which is beneficial to the body. When such bacteria are inhibited, it will cause vitamin deficiency.

2. Other

(1) Avoid mixing with alkaline solution and tap water with high chlorine content.

(2) Oxytetracycline is absorbed incompletely and irregularly after oral administration. Avoid co-administration with dairy products and drugs or feeds containing polyvalent metal ions.

(3) Adult ruminants, equine animals and rabbits are not suitable for oral administration; horses can cause gastroenteritis when injected with this product, so use with caution.

(4) Long-term or high-dose use can induce adverse reactions such as double infection, vitamin B or vitamin K deficiency, and liver toxicity. If diarrhea, pneumonia, nephritis or fever of unknown cause occur during the medication, the possibility of secondary infection should be considered. Once the diagnosis is confirmed, the drug should be stopped immediately and comprehensive prevention and treatment measures should be taken.