LOCKOUT teat sealant aids in the prevention of new intramammary infections.


Like existing teat sealants, LOCKOUT simulates the keratin plug to seal the teat against bacteria. However, LOCKOUT offers several significant enhancements, including a more ergonomic syringe design and a blue paste that's easy to identify upon removal.


View the step-by-step application and removal guide for using LOCKOUT properly and affectively.

Product Description


LOCKOUT aids in the prevention of new intramammary infections by providing a malleable barrier in the teat canal.

  • LOCKOUT teat sealant simulates the keratin plug, the cow’s natural first line of defense, to seal the teat against bacteria.
  • Provides a sterile, antibiotic-free barrier between the udder and the environment.
  • It is recommended that LOCKOUT be used as part of a herd approach to mastitis control.
  • Compatible with conventional dry-cow management practices.
  • Safe for use in non-lactating dairy cows and requires no milk or pre-slaughter withdrawal. If antibiotics are used, follow recommended withdrawal times.

Features & Benefits


  • Visible Blue Paste
    • LOCKOUT is the first non-antibiotic internal teat sealant to feature a visible blue paste that’s easy to distinguish from milk during removal.  
  • Ergonomic Design
    • LOCKOUT maximizes efficiency while minimizing hand discomfort with the syringe’s larger thumb pad, widened wings, and compact size.
  • Fast, Easy & Hygienic Application
    • LOCKOUT comes in single-dose syringes with an easy-to-remove cap, and short tip designed for hygienic insertion.
  • The Quick-Plunge Advantage
    • Administer doses quickly and comfortably with a significantly shorter, half-inch plunger stroke.

Presentation and Dosage

  • LOCKOUT is available in single-dose syringes, containing 4 grams of a sterile, non-antibiotic blue paste composed of 60% bismuth sub-nitrate in a mineral oil vehicle. Each syringe is sufficient for one teat.
  • One pail of LOCKOUT contains 144 syringes for the treatment of 36 animals.

Administration and Removal

INDICATIONS:  LOCKOUT aids in the prevention of new intramammary infections.

ADMINISTRATION:  After last milking at dry-off or prior to first lactation in replacement dairy heifers, thoroughly clean and disinfect teat ends with alcohol swabs provided and leave to air dry. Do not use water with or without disinfectant. If a dry cow antibiotic has been infused, teat should be re-swabbed with alcohol swab provided prior to infusion with LOCKOUT.

A clean, disinfected, and dry teat is essential. Infuse teats in the opposite order to cleansing. Insert tip of a new syringe into teat canal. To minimize LOCKOUT entering the udder,  squeeze top of teat canal at base of udder. Gently depress plunger until teat canal is full. Remove and discard syringe. Treat remaining teats in a similar fashion, using a new syringe for each teat. Do not massage teats or udder following infusion of LOCKOUT.

REMOVAL:  Do not remove LOCKOUT by action of milking machine. The blue color aids in identifying LOCKOUT at the time of removal to reduce the potential for accumulation in milking equipment. Thoroughly hand-strip every teat, 10 to 12 strips per teat before milking. Dispose of any unused product or sealant stripped from an animal in accordance with federal, state, and local requirements. Bucket-milk fresh cows for a minimum of three milkings per normal post-calving procedure.

Safety Information

WITHDRAWAL INFORMATION:  For use in dry dairy cows and replacement dairy heifers only. If accidentally administered to a lactating cow, product can be stripped out by hand. If LOCKOUT is administered following an antibiotic infusion, the withdrawal periods for meat and milk for the antibiotic must be observed. LOCKOUT has a zero-day milk and meat withdrawal when used alone.

USER SAFETY WARNINGS:  Not for use in humans. Keep out of the reach of children. If LOCKOUT gets on skin, wash with soap and warm water. For additional safety information, consult the safety data sheet (SDS).

STORAGE:  Store at room temperature, 60°-85°F (15°-30°C). In very cold temperatures, LOCKOUT may become difficult to administer and should be warmed to room temperature.

Merial is now a part of Boehringer Ingelheim. Lockout is a trademark of Merial.