Merck Ultra Boss Pour-On
Merck Ultra Boss Pour-On
Item # 1133434
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Size: 32 oz.
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Size: 32 oz.
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Grassland (franklin) TN
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Merck Animal Health Ultra Boss Pour-On Insecticide (Permethrin And Piperonyl Butoxide) is used for beef, dairy and lactating cattle; sheep, goats and horses. Target species include: lice, horn flies, face flies, horse flies, stable flies, mosquitoes, black flies and ticks. Protection against horn flies lasts for about 8 weeks.
- Low-volume dosage of pour-on insecticide reduces time and labor
- Effective horn fly control for 8 weeks. Also controls face flies
- Season-long lice control with one application (January through April)
- Special Note: for cattle, horses, sheep and goats, repeat treatment as needed but not more than once every two weeks. for horses, do not saddle horse for 6 hours after application and refrain from washing down area of application. for optimum lice control, two treatments at 14-day intervals are recommended. Ultra Boss Pour-On Insecticide is not effective against cattle grubs
Permethrin and PBO
| Brand | Merck |
|---|---|
| Country of Origin | Imported |
| Active Ingredients | Permethrin |
| Animal Type | Cattle, Goat, Horse, Sheep, Calves |
| Application Method | Pour |
| Concentrated or Ready to Use | Ready to Use |
| Features | Horn fly control for 8 weeks |
| Longevity | 8 weeks |
| Package Quantity | 1 |
| Targeted Fly Types | Lice, Horn Flies, Horse Flies |
| Size | 32 oz. |
| Manufacturer Part Number | 121358 |
Have a question?
Start typing your question and we'll check if it was already asked and answered.
1 - 10 of 19 Questions
Newest questions
Q: Can this or any of these products be used on humans?
16 days ago1 Answer
- A: No, Merck Ultra Boss Pour-On and similar livestock pour-on insecticides must never be used on humans.13 days agoHelpful?
Q: Can it be used on poultry?
a month ago1 Answer
- A: Howdy neighbor! No, you should not use Merck Ultra Boss Pour-On Insecticide on poultry. According to its official EPA product label, this specific oil-based formula is strictly registered for use on cattle, calves, horses, sheep, and goats. Applying a heavy, ready-to-use livestock "pour-on" to birds is highly dangerous because it can cause severe chemical skin burns, mat their feathers (ruining their natural temperature regulation), and potentially result in fatal toxicity.a month agoHelpful?
Q: Dosing is 30ml per 100lbs with a max of 30ml (equal to 1 oz). Do you mix or dilute this with some type of liquid to apply because it'll be pretty difficult to get an ounce evenly distributed down the neck and backline of a cow.
2 months ago1 Answer
- AI-generated, Human-approvedA: No, this product is ready to use and should not be mixed or diluted. It is designed as a low-volume pour-on insecticide to be applied directly along the back and down the face of the animal.2 months agoHelpful?
Q: Can this product be mixed with diesel fuel and used in a back rubber for goats?
2 months ago1 Answer
- A: Merck Ultra Boss Pour-On should be used only according to the product label directions. It is not listed as approved for mixing with diesel fuel or use in a back rubber for goats. We recommend following the labeled application method or contacting Merck Animal Health for guidance on alternative uses.2 months agoHelpful?
Q: What is waiting time on butchering
3 months ago1 Answer
- A: Howdy neighbor! There is absolutely zero days of waiting time required for butchering cattle or sheep after applying Merck Ultra Boss Pour-On Insecticide.3 months agoHelpful?
Q: Does this product work for goat mites?
4 months ago1 Answer
- A: Howdy neighbor! Ultra Boss Pour-On is not labeled to treat goat mites and will not effectively clear up an infestation.4 months agoHelpful?
Q: does the Merck Ultra Boss Pour-On come in less than 1 gallon amounts?
4 months ago1 Answer
- A: Yes, there is an option for a 32 oz bottle on the product page.4 months agoHelpful?
Q: Is this safe for pregnant cows
4 months ago1 Answer
- A: Howdy neighbor! Yes, Merck Ultra Boss Pour-On is completely safe to use on your pregnant cows during any stage of their gestation. This topical insecticide works as a contact treatment with minimal systemic absorption, meaning it poses absolutely no danger to the developing fetus when applied correctly.4 months agoHelpful?
Q: How many cows can one 32oz treat
4 months ago1 Answer
- A: Thank you for your question. The number of cattle that can be treated will vary based on the weight of the animals. According to the manufacturer, the dosage is 3 mL per 100 lb of body weight for cattle, applied along the topline. Customers can use that dosage rate to estimate how many animals a 32 oz bottle will treat based on their herd’s average weight.4 months agoHelpful?
Q: Can I apply with a spray bottle ?
6 months ago1 Answer
- AI-generated, Human-approvedA: The specified application method for this product is as a pour-on, rather than a spray. It is designed for low-volume dosage to be applied along the back and down the face of the animal.5 months agoHelpful?
1 - 10 of 19 Questions
Q&As
Have a question?
Start typing your question and we'll check if it was already asked and answered.
1 - 10 of 19 Questions
Newest questions
Q: Can this or any of these products be used on humans?
16 days ago1 Answer
- A: No, Merck Ultra Boss Pour-On and similar livestock pour-on insecticides must never be used on humans.13 days agoHelpful?
Q: Can it be used on poultry?
a month ago1 Answer
- A: Howdy neighbor! No, you should not use Merck Ultra Boss Pour-On Insecticide on poultry. According to its official EPA product label, this specific oil-based formula is strictly registered for use on cattle, calves, horses, sheep, and goats. Applying a heavy, ready-to-use livestock "pour-on" to birds is highly dangerous because it can cause severe chemical skin burns, mat their feathers (ruining their natural temperature regulation), and potentially result in fatal toxicity.a month agoHelpful?
Q: Dosing is 30ml per 100lbs with a max of 30ml (equal to 1 oz). Do you mix or dilute this with some type of liquid to apply because it'll be pretty difficult to get an ounce evenly distributed down the neck and backline of a cow.
2 months ago1 Answer
- AI-generated, Human-approvedA: No, this product is ready to use and should not be mixed or diluted. It is designed as a low-volume pour-on insecticide to be applied directly along the back and down the face of the animal.2 months agoHelpful?
Q: Can this product be mixed with diesel fuel and used in a back rubber for goats?
2 months ago1 Answer
- A: Merck Ultra Boss Pour-On should be used only according to the product label directions. It is not listed as approved for mixing with diesel fuel or use in a back rubber for goats. We recommend following the labeled application method or contacting Merck Animal Health for guidance on alternative uses.2 months agoHelpful?
Q: What is waiting time on butchering
3 months ago1 Answer
- A: Howdy neighbor! There is absolutely zero days of waiting time required for butchering cattle or sheep after applying Merck Ultra Boss Pour-On Insecticide.3 months agoHelpful?
Q: Does this product work for goat mites?
4 months ago1 Answer
- A: Howdy neighbor! Ultra Boss Pour-On is not labeled to treat goat mites and will not effectively clear up an infestation.4 months agoHelpful?
Q: does the Merck Ultra Boss Pour-On come in less than 1 gallon amounts?
4 months ago1 Answer
- A: Yes, there is an option for a 32 oz bottle on the product page.4 months agoHelpful?
Q: Is this safe for pregnant cows
4 months ago1 Answer
- A: Howdy neighbor! Yes, Merck Ultra Boss Pour-On is completely safe to use on your pregnant cows during any stage of their gestation. This topical insecticide works as a contact treatment with minimal systemic absorption, meaning it poses absolutely no danger to the developing fetus when applied correctly.4 months agoHelpful?
Q: How many cows can one 32oz treat
4 months ago1 Answer
- A: Thank you for your question. The number of cattle that can be treated will vary based on the weight of the animals. According to the manufacturer, the dosage is 3 mL per 100 lb of body weight for cattle, applied along the topline. Customers can use that dosage rate to estimate how many animals a 32 oz bottle will treat based on their herd’s average weight.4 months agoHelpful?
Q: Can I apply with a spray bottle ?
6 months ago1 Answer
- AI-generated, Human-approvedA: The specified application method for this product is as a pour-on, rather than a spray. It is designed for low-volume dosage to be applied along the back and down the face of the animal.5 months agoHelpful?
1 - 10 of 19 Questions
Reviews
1 to 4 of 21 Reviews .
1 – 4 of 21 Reviews
Most Recent
Anonymous
Review 1
5 out of 5 stars.
Fly repellant
2 months ago
t works well on cows
SweepstakesYes
4C Cattle
Review 1
5 out of 5 stars.
Good Stuff!
a year ago
Very good product. One of best products we have tried to keep flies at a minimum.
Product Used Since : 9/5/2025
Originally posted on SCBT
Julie G
Review 1
5 out of 5 stars.
Quick Easy Fly Control
a year ago
I only have a couple steers but I saw immediate results with fly control after applying Ultra Boss. Quick and easy to use.
Product Used Since : 7/3/2025
Originally posted on SCBT
Equinista
Review 1
5 out of 5 stars.
Happier horses
a year ago
Love this product. I combine it with fly spray when the flies are extremely bad.
Product Used Since : 7/8/2025
Originally posted on SCBT