Doxycycline is a semi-synthetic tetracycline antibiotic derived from oxytetracycline. The hydrochloride salt is light yellow or yellow crystal powder, soluble in water, and the aqueous solution is more stable than tetracycline and oxytetracycline.

【Pharmacological action】

This product is a semi-synthetic tetracycline antibiotic with broad spectrum, high efficiency and low toxicity. Its antimicrobial spectrum is similar to that of oxytetracycline, but its antimicrobial activity is 2-10 times stronger than that of oxytetracycline. It has low concentration of antibacterial and high concentration has bactericidal effect. It is still effective against oxytetracycline and tetracycline-resistant Staphylococcus aureus, and has no obvious cross-resistance with natural tetracyclines. It has strong antibacterial activity against Gram-positive bacteria and Gram-negative bacteria, and is effective against mycoplasma, chlamydia, rickettsia, spirochetes, Eperythrozoonosis and certain protozoa.

Doxycycline also has antitussive, expectorant and antiasthmatic effects.

【Mechanism of action】

Doxycycline reversibly binds to receptors on the 30S subunit of bacterial ribosomes, interferes with the formation of ribosomal complexes between tRNA and mRNA, prevents peptide chain elongation and inhibits bacterial protein synthesis, thereby rapidly inhibiting bacterial growth and reproduction.

【Pharmacokinetics】

This product is well absorbed by internal medicine and the effective blood concentration is maintained for a long time. After absorption, it is widely distributed in the heart, kidney, lung, muscle, intestine, joint cavity, breast tissue, brain tissue and genitourinary system. It can be used for the treatment of infections in various tissues of the whole body. This product is a time-dependent antibiotic with a long half-life and a long post-antimicrobial effect (PAE), so the effect is more durable.

This product is fat-soluble, easier to penetrate through body tissues and body fluids, including cerebrospinal fluid, prostate and eyes, more suitable for the treatment of conjunctivitis and systemic infection.

【Indications】

1. Respiratory diseases: commonly used in mycoplasma pneumonia or respiratory disease syndrome (PRDC), actinobacillus pleuropneumonia.

2. Digestive tract disease: used for diarrhea caused by E.coli and salmonella, and also for ileitis, swine dysentery, etc.

3. Systemic infections: For piglet edema disease, various streptococci, eperythrozoonosis, toxoplasmosis, chlamydia and rickettsia infection.

4. Reproductive disorders in sows:

1) Used in sow mastitis-hysteritis-galactophore syndrome, sows postpartum temperature rise, uterine lochia is not clean, etc.

2)Abortion of pregnant sows caused by leptospira and chlamydia.

【Medicine interactions】

1. Doxycycline has a significant synergistic effect with florfenicol and/or tiamulin, which is one of the major clinical compatibility combinations.

2. It has a stabilizing effect in combination with trimethoprim (TMP).

3. It is not suitable to be used with traditional Chinese medicines containing calcium, magnesium, aluminum and iron such as stone, shellfish, bones, terpenoids, lipids, etc. Heavy metals and high calcium in feed can affect the absorption of doxycycline.

【Usage and dosage】

Usage: through feed or water.

Dosage: 3~5mg/kg body weight, once a day, for 5 to 7 days.

Through feed: This product is 160-240g/ton, for 5 to 7 days.

Water administration: 60-100g/ton of this product, used for 5 to 7 days.

In production, doxycycline is often combined with tiamulin and/or florfenicol, the dosage can be reduced, and the antibacterial spectrum is wider and the antibacterial effect is better.

【Common medication regimen】

4. Miaokemei 125g +50% Liduomeixin 160g + Fukexin300g / ton of feed, after weaning, before and after 12 weeks of age, 18 weeks of age, respectively, for 7 to 10 days, for respiratory tract disease syndrome, eperythrozoonosis, chlamydia infection, and systemic bacterial infections.

5. Miaokemei 125g +50% Liduomeixin 160g + sulfa chloride sodium chloride (including TMP) 400g (also available sulfa-6-methoxypyrimidine) / ton of feed, sows 10 days before and after farrowing, for hysteritis, mastitis and no milk syndrome.

【Comparisons between Liduomeixin and similar products】

Table 1 Comparison of different doxycycline hydrochloride

【Features】

1. Stable in water, does not complexes with heavy metal ions in water.

2. Controlled release, sustained release (fast before, and after slow), enabling rapid blood concentration and longer duration of action.

3. High calcium or other heavy metal ions in the feed have little effect on the power of Liduomeixin, and the bioavailability is high.

【Precautions】

Long-term use can cause dysbacteriosis of the gastrointestinal tract, causing secondary infection.

【Withdrawal time】

Pig 28 days

【Packing specification】

Content: 50%

Package: 100g/bag, 100 bags/box