TYLOSIN, A MACROLIDE FOR VETS
Tylosin (Brand Name: Tylan) is a macrolide antibiotic widely used in veterinary medicine. Its use in humans is not permitted. Tylosin is available in two salt forms Tylosin Tartrate and Tylosin Phosphate. Tylosin is related to erythromycin. Tylosin is composed of a 16-atom lactone ring, whereas erythromycin has a 14-atom ring. Some other members of macrolide antibiotics are Tilmicosin, Azithromycin, Tulathromycin, Spiramycin, and Erythromycin. Tylosin serves both as a treatment for bacterial infections and also as a feed additive to promote animal health and growth, particularly in livestock such as poultry, cattle, and swine. An interesting fact about Tylosin (Tylosin Tartrate) is that it is approved by the FDA as of 2014 to be used in miscellaneous minor food-producing animals such as bees for American foulbrood.
Tylosin (Tylan) is a bacteriostatic agent, that works by inhibiting the growth and reproduction of bacteria instead of killing them. Therefore, Tylosin is a valuable tool in managing bacterial populations without fully disrupting the microbial ecosystem within the animal’s body. Tylosin has a broad spectrum of activity against Gram-positive bacteria. These bacteria include many pathogenic strains responsible for respiratory, gastrointestinal, and skin infections in animals.
Tylosin exhibits strong antibacterial activity against Gram-positive bacteria due to its ability to interfere with protein synthesis. It targets the 50S ribosomal subunit in these organisms. Like other macrolides, Tylosin inhibits translocation during translation. Therefore, it effectively halts the formation of essential proteins and ultimately leads to bacterial growth inhibition. This activity makes Tylosin highly effective against a range of Gram-positive pathogens, including Clostridium perfringens, Staphylococcus, Streptococcus, Trueperella spp, Erysipelothrix, Actinomyces and Corynebacterium species, which are common in veterinary medicine and often cause respiratory and skin infections.
Studies have demonstrated that Tylosin’s lipophilic nature allows it to penetrate well into bacterial cells, which contributes to its efficacy against Gram-positive bacteria. The lipophilicity enhances Tylosin’s accumulation within these bacterial cells, making it more potent and enabling sustained activity over time. Additionally, following oral administration in Broiler chickens, it achieves a high mean systemic bioavailability of 90.29%, reflecting efficient absorption and bioavailability within the body’s pharmacokinetic profile.
Due to its broad spectrum against Gram-positive organisms, Tylosin is widely applied in animal health, especially in treating infections in livestock. Tylosin is effective in managing bovine respiratory disease complex (BRDC) and swine dysentery, which are commonly associated with Gram-positive pathogens. Studies also support its use as a prophylactic and therapeutic agent in managing infections in poultry, cattle, and swine.
In adult Cattle, Tylosin (Tylan) is indicated for respiratory infections, metritis caused by Gram-positive microorganisms, mastitis caused by Streptococcus spp., Staphylococcus spp., and interdigital necrobacillosis, i.e., panaritium or foot rot.
In Calves, Tylosin is indicated for respiratory infections and necrobacillosis. In Pigs, Tylosin is indicated for Enzootic pneumonia, hemorrhagic enteritis, erysipelas, metritis, and Arthritis caused by Mycoplasma spp. and Staphylococcus spp.
Tylosin’s effectiveness against Gram-negative bacteria is more restricted, but it is still beneficial for targeting specific pathogens within this group under certain conditions. These conditions sometimes include increasing the dose rate of Tylosin.
Tylosin (Tylan) demonstrates exceptional activity against Mycoplasma species, which are common and problematic pathogens found in mammalian and avian hosts, particularly impacting the respiratory system. In veterinary applications, Tylosin is used extensively to manage Mycoplasma infections in livestock, such as chronic respiratory disease (CRD), complicated chronic respiratory disease (CCRD) in poultry, and enzootic pneumonia in swine.
Studies have shown that Tylosin achieves high intracellular concentrations, enabling it to target pathogens residing within host cells, particularly in respiratory and reproductive tissues where Mycoplasma infections are prevalent. This tissue penetration enhances Tylosin’s efficacy in combating infections and reducing clinical symptoms associated with Mycoplasma.
Tylosin is naturally produced as a secondary metabolite through the fermentation of Streptomyces fradiae, a soil-dwelling bacterium. This natural origin has enabled researchers to cultivate and optimize Streptomyces fradiae for large-scale production, ensuring a steady and sustainable supply of Tylosin for veterinary and agricultural uses.
In addition to its antibacterial properties, Tylosin is known for its role in improving animal productivity by enhancing feed efficiency and promoting growth, especially in intensive farming environments. This application has made Tylosin a common additive in animal feed, contributing to improved overall health and productivity in farm animals.
As per European Pharmacopeia, Tylosin Tartrate which is a form of Tylosin is almost white or slightly yellow, hygroscopic powder. Whereas Tylosin Phosphate is a yellow or brownish-yellow, viscous liquid. Tylosin Tartrate is used where water solubility is needed while Tylosin Phosphate is mostly incorporated in feed as a growth promoter.
In the United States, the Food and Drug Administration (FDA) has permitted the use of Tylosin in honey production under regulation No. 21 CFR 556.746. This authorization allows beekeepers to use Tylosin in managing bacterial infections such as American Foulbrood, a severe and highly contagious disease that affects honeybee colonies. Tylosin’s use in honey production is crucial for controlling these infections, which can decimate bee populations and harm honey yields. Japan’s Ministry of Food and Drug Safety (MFDS) has similarly authorized Tylosin for use in honey production, extending the approval to products derived from bees, including royal jelly. Royal jelly is a nutrient-rich secretion used by honeybees to nourish their larvae and the queen bee, making it a significant product in apiculture.
In contrast, Europe has more restrictive regulations on Tylosin use in honey production. The European Union’s Regulation (EC) No. 37/2010 authorizes Tylosin only in food-producing species other than honeybees, thereby excluding honey and related bee products from its application. This restriction reflects Europe’s cautious approach to antibiotic residues in food products.
To sum it up, Tylosin is a macrolide antibiotic, approved for veterinary use. We recommend using Tylosin under the supervision of a veterinarian who may better guide you. Your veterinarian is better informed about drug resistance and disease prevalence in your particular state or city.