Lifei Powder Veterinary Grade API is supplied as a dry powder for downstream conversion into regulated veterinary dosage forms. The application routes below are restricted to industrial processing lines for registered veterinary medicinal products and medicated feed; the powder is not licensed for direct administration without formulation. In each route, the compliance anchor, addition ratio, production process, and finished form are embedded in the technical description.

In swine oral premix and granulated feed manufacturing, the API is first converted into an intermediate premix because direct addition to the final feed mixer produces unacceptable assay variation when the API mass fraction in the final feed falls below 0.01% w/w. The dry powder is pre-blended with calcium carbonate or rice-husk carrier at an API addition ratio of 2.0%–10.0% w/w, most commonly 5.0% w/w, in a 500-kg double-ribbon mixer operated at 38 rpm for 12 min. Blend uniformity is assessed by sampling at least 10 points and demonstrating a coefficient of variation not exceeding 5.0%, consistent with ISO 6497:2002 sampling principles and the homogeneity requirements of Regulation (EU) 2019/4 Annex II. On production-scale double-ribbon mixers, a worn ribbon-to-wall clearance greater than 6 mm causes carrier-bound API to accumulate at the discharge gate, producing CV values above 8.0% even after 20 min mixing; line setup therefore includes clearance checks and discharge-gate sweep bars. The intermediate premix is diluted to final medicated feed at 1.0–2.0 kg/tonne, delivering 50–100 g API per tonne at 5.0% w/w premix strength, with the exact dose fixed by the authorised therapeutic indication, species age, and withdrawal period. For granulated feed, the diluted mixture is conditioned at 70–85°C and 16–18% moisture for 30–90 s, then passed through a pellet press with a 3.5:1 compression ratio and 2.5–3.0 mm die aperture. Finished forms include medicated premix sachets, oral granules packed in 1 kg or 5 kg foil-lined bags, and pelleted complete feed.

Can the powder be re-packed into soluble drinking-water formulations without additional micronization?

During reconstitution into drinking-water soluble powders, clarity and dispersion performance govern the formulation rather than final feed homogeneity. The API is dry-blended with lactose monohydrate, anhydrous citric acid, sodium bicarbonate, and colloidal silicon dioxide at 0.5% w/w to control moisture pickup. The concentrated soluble powder is prepared at an API addition ratio of 10%–50% w/w, and the field dilution is 0.05%–0.2% w/v of formulated powder in drinking water, equivalent to 50–200 g powder per 100 L. The downstream process includes dry sieving through 0.500 mm mesh and air-jet milling to a D90 of 25–40 µm when incoming particle-size D90 exceeds 75 µm, so that complete reconstitution in water at 25°C occurs within 5 min under paddle agitation at 60 rpm. Water hardness above 300 ppm CaCO₃ can produce precipitation; disodium EDTA at 0.05% w/w is incorporated only when hardness is confirmed by on-site titration. The solution is filtered through a 45 µm inline filter and filled into metallised sachets or HDPE jerry cans. Compliance for soluble powders intended for oral administration includes clarity and redispersibility checks under Ph. Eur. 2.9.1 and the general provisions of Regulation (EU) 2019/6. The reconstituted solution is assessed for assay stability after 24 h at 25°C and 5°C. Finished forms include water-soluble powder sachets, oral solution concentrates, and drench solutions in multi-dose containers.

Injectable manufacturing requires terminal sterilisation or aseptic filtration after oxygen and pH control

Where sterile injectable manufacturing is the downstream route, oxygen and pH control precede terminal sterilisation or aseptic filtration of the API solution. Lifei Powder API is dissolved at 5.0%–10.0% w/v in water for injection; pH is adjusted to 6.0–7.0 with diluted sodium hydroxide or hydrochloric acid, and isotonicity is achieved with 0.9% w/v sodium chloride or 4.5% w/v mannitol when a lyophilized cake is required. Dissolution is performed at 60–70°C under nitrogen sparging to keep dissolved oxygen below 0.5 mg/L, followed by sterile filtration through a 0.22 µm PVDF membrane. If terminal moist-heat sterilisation is selected, a cycle of 121°C for 15 min is applied only after D-value and degradation studies confirm less than 0.5 log potency loss; otherwise aseptic filtration is used. For lyophilized vials, the filtered solution is filled into 20 mL Type I glass vials, partially stoppered, and lyophilized with shelf temperature profiles of -40°C for 240 min freezing, primary drying at -20°C and 0.2 mbar for 20 h, and secondary drying at 25°C for 6 h. Silicone tubing compatibility on filling machines should be verified because the API may bind to silicone elastomer at pH below 5.0. The powder should not be blended with amine-based rubber stoppers or strong oxidising agents without compatibility data. Compliance tests include bacterial endotoxin per USP <85> or Ph. Eur. 2.6.14, container closure integrity per USP <1207>, and subvisible particulate matter per Ph. Eur. 2.9.19. Finished forms are single-dose vials, multi-dose vials preserved with 1.5% v/v benzyl alcohol where authorised, and lyophilized cakes for reconstitution with 20 mL WFI.

When tablet compression demands dry granulation instead of direct compression

Dry granulation replaces direct compression for companion animal tablets when the API particle-size distribution and bulk density create segregation risk at rotary press speeds above 60,000 tablets/h. The addition ratio in the tablet core ranges from 2.0% w/w to 20.0% w/w, with common dose strengths of 5 mg, 10 mg, and 50 mg API per 150–400 mg core. The API is pre-mixed with microcrystalline cellulose PH-102 at 35% w/w, lactose monohydrate at 25% w/w, croscarmellose sodium at 3% w/w, and sodium stearyl fumarate at 1% w/w. The powder blend is passed through a roller compactor at roll force 6–12 kN/cm, roll speed 10 rpm, and gap width 1.5 mm; the resultant ribbons are milled through a 0.8 mm screen to produce granules with fines fraction controlled to ≤30%. Tableting is performed on a rotary press at 10–18 kN compression force, producing tablet hardness 60–90 N and friability below 1.0% per Ph. Eur. 2.9.7. Dose uniformity is verified per USP <905> and Ph. Eur. 2.9.40. Direct compression is avoided when the API fraction exceeds 15% w/w because flow function coefficient falls below 4 and compression weight variation exceeds 2.0% RSD on longer runs. If ambient relative humidity exceeds 60% RH, the powder is pre-dried in a fluid-bed dryer at 40°C for 60 min before blending. Finished forms include scored tablets, coated tablets, and chewable tablets where authorised for companion animals.

Following roller-compacted granulation, capsule filling provides a dose-titration route when exact low-dose increments cannot be achieved by tablet splitting. Capsule fill weight is set at 120–350 mg, with API content between 5.0% w/w and 40.0% w/w for dose strengths from 2.5 mg to 100 mg. The granulated blend is lubricated with 0.5% w/w magnesium stearate and filled on an intermittent-motion capsule machine at 60,000 capsules/h; HPMC or hard gelatin capsule shells may be used, with HPMC preferred when moisture-sensitive formulations require moisture content below 4.0%. Capsule weight variation is checked every 30 min with an acceptance limit of ±3.0% relative to target, and dissolution is assessed per USP <711> or Ph. Eur. 2.9.3. Finished forms are hard gelatin capsules, HPMC capsules, and veterinarian-administered capsule blisters for weight-adjusted dosing.

Aquaculture premix extrusion and post-pellet vacuum coating in sinking feed lines

Preconditioning of aquafeed mash before extrusion determines API recovery in medicated sinking feed. The premix is prepared at an API addition ratio of 1.0%–10.0% w/w on a wheat middlings or starch carrier, then added to the final feed at 0.5–5.0 kg/tonne; at 5.0% w/w premix strength this delivers 25–250 g API per tonne depending on the authorised dose and species. Where the API is not formally validated for thermal stability above 110°C, the post-pellet vacuum coating route is used: feed passes through twin-screw extrusion at 90–105°C barrel temperature, 25–30% moisture, and 2.0–3.0 mm die diameter, followed by drying at 75°C to moisture below 9%. The API is suspended in fish oil or hydrogenated soybean oil and applied in a vacuum coater at 0.1–0.3 bar negative pressure for 8–12 min, producing a coating uniformity CV below 10%. Production-scale vacuum coaters with paddle speed 15–25 rpm and liquid spray pressure 1.5–2.5 bar reduce leaching of the API into pond water; batch-to-batch variation in carrier oil cloud point can alter spray viscosity, so oil viscosity is held at 2–4 mPa·s at 35°C in temperature-controlled jacketed tanks. Leaching is measured by soaking pellets for 60 min at 25°C and must remain within the authority-approved limit. Compliance anchors are Regulation (EU) 2019/4 for medicated feed, 21 CFR 225.1 and 21 CFR 226.1 for US medicated feed CGMPs, and residue control under Codex Alimentarius. Published data for the specific Lifei Powder API through twin-screw extrusion above 110°C is limited; therefore post-pellet vacuum coating is the default when thermal degradation of the active substance has not been formally excluded. Finished forms are extruded sinking feed pellets, top-coated post-pellet feed, and pond premix sachets.