What’s a dose got to do with it?

Ensure product efficacy by dosing and storing dewormers correctly

Operating costs continue to rise, making it more critical than ever for producers to ensure they are getting optimal results from their cattle dewormer. To get the best result, it pays to dose and store the product correctly since both factors can affect product efficacy. 

To determine proper dosage, it is essential to have an accurate weight of each animal — underestimating weight can lead to underdosing of dewormers.1 Several methods are available for determining an animal’s weight, including weight tapes and visual observation; however, using approved and properly calibrated livestock scales are the most accurate and consistent for determining body weight.2 Visual observation is usually very inaccurate and not recommended for use when determining medication dosages for which weight is important.2

“The average cow in the United States weighs about 1,350 pounds,”1 Gary Sides, Ph.D., Cattle Nutritionist, Pfizer Animal Health Veterinary Operations. “However, most producers are generally dosing to a 1,000-pound cow when many weigh much more than that. By underdosing, we run the risk of allowing parasites to become resistant.”

In the U.S., veterinarians, producers and economists estimate annual parasite-related losses to the livestock industry at more than $100 million.3 Therefore, it is important to administer injectable dewormers, whenever possible, to help reduce opportunity for a pour-on product to be licked off by other cattle, absorbed by dirt on the animal’s hide or affected by other factors.4

To control parasites — and help ensure optimal performance of your herd — Dr. Sides recommends producers look for broad-spectrum dewormers like DECTOMAX® 1% Injectable. DECTOMAX Injectable treats and controls Ostertagia ostertagi, also known as the brown stomach worm, for up to 21 days and is safe for pregnant cows, newborn calves and bulls.5

“By using an injectable product, you ensure that the entire dose gets in the animal,” Dr. Sides says. “There are less negative effects for injection site lesions and you can get better plasma and tissue concentration levels compared with a pour-on.”

By taking extra precautions with the storage and handling of dewormers, producers can help ensure a product’s effectiveness. Be sure to check the label for storage temperature instructions and follow them closely. For example, the DECTOMAX Injectable label advises storage below 86°F.6

“Read the label directions before using any animal health product,” Dr. Sides says. “This reduces the risk of side effects, tissue residues, along with a multitude of other reasons besides efficacy and cost.”

Important Safety Information: DECTOMAX Injectable has a 35-day pre-slaughter withdrawal period. Do not use in dairy cows 20 months of age or older. DECTOMAX has been developed specifically for cattle and swine. Use in dogs may result in fatalities.

Full Product Label

For more information, contact:

Becky Lambert
Pfizer Animal Health

Kori Conley
Bader Rutter

1 Pater S. How much does your animal weigh? Dec. 2007. Available at: http://ag.arizona.edu/backyards/articles/winter07/p11-12.pdf. Accessed Feb. 25, 2011.
2 McMurry B. Cow Size is Growing. Feb. 2009. Available at: http://beefmagazine.com/genetics/0201-increased-beef-cows/. Accessed Feb. 21, 2011.
3 Strickland JE. Internal parasite control in cattle. The University of Georgia Cooperative Extension. Bulletin 1086. November 1992. Available at: http://www.caes.uga.edu/Publications/displayPDF.cfm?pk_ID=6196. Accessed Sept. 22, 2010.
4 Bousquet-Me´lou et al. Endectocide exchanges between grazing cattle after pour-on administration of doramectin, ivermectin and moxidectin. International Journal for Parasitology 34; 1299–1307. August 2004.
5 Pfizer Animal Health Market Research, 2011.
6 DECTOMAX Injectable product label.



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