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


This treatment applies to the following species:
Manufacturer: VetOne


Dry Cow Intramammary Teat Sealant Device

As an aid in the prevention of new intramammary infections throughout the dry period

Each syringe contains 4g intramammary paste

Containing 65% Bismuth Subnitrate

For use in nonlactating dairy cattle

For animal use only

Read Entire Package Insert Carefully Before Using This Product

BoviBlock™ is a sterile, antibiotic-free, off-white smooth paste. It is presented, ready to use, in syringes, each containing 4 g of intramammary infusion composed of 65% Bismuth Subnitrate, in a mineral oil vehicle. BoviBlock is indicated as an aid in the prevention of new intramammary infection throughout the dry period by providing a malleable barrier in the teat canal. This results in a reduction in the incidence of clinical mastitis in the dry period.

It is recommended that BoviBlock be used as part of a herd approach to dry cow management and mastitis control.

WITHDRAWAL INFORMATION: For use in dry cows only. Zero-day milk and meat withdrawal when used alone.

If BoviBlock is administered following an antibiotic infusion, the withdrawal periods for meat and milk for the antibiotic should be observed.


Keep out of reach of children. For animal treatment only. If BoviBlock gets on skin, wash with soap and warm water. If accidentally administered to a lactating cow, product can be stripped out by hand. An SDS may be obtained by calling Norbrook at 1-866-591-5777 or visiting the Norbrook, Inc. website at

Adverse Reactions

Mastitis-causing bacteria introduced into the teat at the time of infusion of BoviBlock have been associated with adverse reactions. Each teat must be cleaned and disinfected prior to infusion of BoviBlock. See below for instructions for administration of infusion products.


BoviBlock should be stored at room temperature 59°-86°F (15°-30°C). In very cold temperatures BoviBlock may become difficult to administer and should be warmed to room temperature. Individual tubes should not be immersed in water. The BoviBlock bucket can be lowered into a 5 gallon bucket filled with warm water to warm the tubes.

BoviBlock Indications

BoviBlock is indicated as an aid in the prevention of new intramammary infections of dairy cattle throughout the dry period.

Dosage and Administration

After last milking at dry-off, clean and disinfect the teats with alcohol wipes provided. Gently pinch the base of the teat near the udder attachment to close the teat canal. Infuse entire contents of one syringe of BoviBlock into each quarter by inserting the nozzle into the teat and applying gentle continuous pressure to the plunger until the paste is expressed. BoviBlock must remain in the teat canal to be effective.

Do not massage teat or udder following infusion. If an antibiotic is infused into the teat, the teat should be re-wiped with the alcohol wipe provided prior to infusion with BoviBlock. A clean, disinfected and dry teat is essential, as BoviBlock possesses no antimicrobial activity. It is advisable to use an appropriate teat disinfectant following the infusion.

BoviBlock is presented in syringes with a 2-Stage tip. This 2-Stage tip allows for either full or partial insertion into the teat orifice. Partial insertion only is preferable, as it may prevent unnecessary damage to the teat orifice and reduce the risk of infection. Full insertion may be needed for large teat orifices.

Option 1: For short tip intramammary administration

Option 2: For long tip intramammary administration

REMOVAL: Do not remove BoviBlock by action of the milking machine.

To reduce the potential for BoviBlock accumulation in milking machines, aggressively hand-strip BoviBlock 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.

Simple steps to avoid introducing infections during administration of intramammary infusions.

1. Do not place individual syringes in warm/hot water during cold weather.

2. Dry cows off abruptly rather than gradually.

3. Clean teat ends as thoroughly as possible with alcohol and leave to air dry. DO NOT use water with or without disinfectant.

4. Clean the two teats furthest away first, followed by the two closest.

5. Ensure the teats are clean and dry before infusing BoviBlock.

6. Infuse the teats in the opposite order to cleansing: i.e. infuse the closest two teats first, followed by the two furthest away.

7. After infusing, dip teats in teat dip or spray with disinfectant and leave cows standing in yard for at least half an hour to allow the teat canal to close.

8. Check cows regularly for signs of mastitis during the first week after drying off.

Use Only as Directed

For Animal Use Only - Not for Human Use

Keep Out of Reach of Children

Discard Empty Tubes - Do Not Reuse

Read Insert for Complete Directions

Manufactured for: MWI, Boise, ID 83705

Manufactured by: Norbrook Laboratories Limited, Newry, BT35 6PU, Co. Down, Northern Ireland

Made in the UK

BoviBlock™ is a trademark of MWI

Revised: 11/17





144 x 4g syringes

V1 510282



Label Iss. 11/17

CPN: 1315254.0

Distributed by MWI Animal Health

3041 W. PASADENA DR., BOISE, ID, 83705
Customer Service:   888-694-8381
Toll-Free:   800-824-3703
Every effort has been made to ensure the accuracy of the BoviBlock information published above. However, it remains the responsibility of the readers to familiarize themselves with the product information contained on the US product label or package insert.

Copyright © 2018 North American Compendiums. Updated: 2018-02-26