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ShutOut (Canada)

This page contains information on ShutOut for veterinary use.
The information provided typically includes the following:
  • ShutOut Indications
  • Warnings and cautions for ShutOut
  • Direction and dosage information for ShutOut


This treatment applies to the following species:
Company: Merck Animal Health

Teat sealant device for use in dry cows

For veterinary use only. Not for use in humans. Keep out of reach of children.

Read Entire Package Insert Carefully Before Using This Product


Each syringe of ShutOut contains 4 g of a sterile, non-antibiotic, smooth intramammary paste containing 2.6 g of bismuth subnitrate. It is presented in a ready-to-use syringe for intramammary infusion.

ShutOut Indications

ShutOut is indicated as an aid in the prevention of new intramammary infections of dairy cattle throughout the dry period by forming a barrier in the teat canal. This results in a reduction in the incidence of clinical mastitis in the dry period.

It is recommended that ShutOut be used as part of a preventive integrated and holistic herd health approach to dry cow management and mastitis control.

Dosage and Administration

After last milking at dry-off, clean and disinfect the teats with the alcohol wipes provided. Infuse the entire contents of one syringe of ShutOut into each quarter by inserting the nozzle into the teat and applying gentle continuous pressure to the plunger until the paste is expressed. Do not massage the teat or udder following infusion. If an antibiotic is infused into the teat, the teat should be re-wiped with the alcohol wipes provided prior to infusion with ShutOut. A clean, disinfected and dry teat is essential, as ShutOut does not have any antimicrobial property.

ShutOut has the option to either use the short (Figure 1) or the long tip of the syringe.

According to National Mastitis Council recommendations, using the short tip is preferred because it has been shown to result in fewer new intramammary infections.

Figure 1 - Short tip insertion

Studies recommend partial insertion of 2-3 mm to avoid increase in infection and damaging of the teat canal.1,2

REMOVAL: Do not remove ShutOut by action of the milking machine. To reduce the potential for ShutOut accumulation in milking machines, aggressively hand-strip ShutOut out of every quarter, 10 to 12 strips per quarter, before milking fresh cows. Bucket-milk fresh cows for a minimum of three milkings, if possible.


For use in dry cows only. Zero-day milk and meat withdrawal when used alone. If ShutOut is administered following an antibiotic infusion, the withdrawal periods for meat and milk for the antibiotic must be observed.

CAUTIONS: For veterinary use only. Not for use in humans. Keep out of reach of children.

ShutOut does not have any antimicrobial properties. Therefore, unintended introduction of mastitis-causing bacteria needs to be avoided by following proper administration guidelines and sanitation.

To control this risk further, it is recommended to lower milk production towards dry off to prevent milk leakage during and directly after administration of ShutOut, to aseptically administer the product into the teat using a predefined protocol, to ensure a clean, dry and comfortable environment during dry off and good environmental hygiene during and directly after calving.

It is also good practice to observe dry cows regularly for signs of clinical mastitis. If a sealed quarter develops clinical mastitis, the affected quarter should be stripped out manually before appropriate therapy is instituted.

In cows that may have subclinical mastitis, ShutOut may be used following administration of a suitable dry cow antibiotic treatment to the infected quarter.

Please consult with your herd health veterinarian for therapy recommendations for cows with clinical and subclinical mastitis.

To reduce the risk of contamination, do not immerse the syringe in water.

Use the syringe only once.

Do not administer any other intramammary product following administration of ShutOut.

Lactation: If ShutOut is accidentally administered to a lactating cow, the seal can be stripped out manually.

USER SAFETY: If ShutOut gets on skin, wash with soap and warm water. If irritation persists, seek medical advice and show the label to the doctor. If you know that you are allergic to bismuth salts, avoid using this product.

Wash hands after use.

Keep out of reach of children.


ShutOut should be stored at room temperature (15°-30°C). In very cold temperatures, ShutOut may become difficult to administer and should be warmed to room temperature. Individual syringes should not be immersed in water. If there is a need to warm the syringes, the ShutOut bucket could be lowered into a distinct large bucket filled with warm water.

Intervet Canada Corp., Subsidiary of Merck & Co., Inc., 16750, route Transcanadienne, Kirkland, QC H9H 4M7

1 866 683-7838

Merck is a registered trademark of Merck Canada Inc.

™ Intervet International B.V. Used under license.


1. Boddie RL, Nickerson SC. Dry cow therapy: Effects of method of drug administration on occurrence of intramammary Infection. J Dairy Sci. 1986; 69:1, 253-257.

2. McDougall S. Management factors associated with the incidence of clinical mastitis over the non-lactation period and bulk tank somatic cell count during the subsequent lactation. NZ Vet J. 2003; 51:2, 63-72.

24 syringes, 144 syringes

356480 R1

CPN: 1208320.0

Intervet Canada Corp.

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