Health Ranch

Welcome to Health Ranch, where you can find information and resources to help you put the health and well-being of your cattle at the top of the priority list.

Crunching the numbers: Extended-release deworming may offer the most value this spring.

An extended-release dewormer may be what you need for long-term rewards.

February 1, 2024

4 Min Read
Crunching the numbers on deworming options
Submitted by Boehringer Ingelheim

“My grandfather always said, ‘Sometimes, you get what you pay for,’” recalled Jody Wade, DVM, Boehringer Ingelheim.

When it comes to dewormers, that seems to be true. Dr. Wade is referencing extended-release dewormers, which cost more than traditional dewormers.

“There is five times more of the active ingredient in an injectable, extended-release dewormer than what you have with other products,” he explained. “It also lasts two to three times longer, in most cases. It does give you more bang for your buck.”

And with the cattle industry’s market volatility, every dollar counts.

For those who are raising or purchasing replacement heifers, or considering shifting more to that model again, the value of those heifers is tied directly to their health and reproductive efficiency. Since deworming is often considered the herd management practice that can yield the greatest return on investment, it pays to pay attention to the products you’re using.

Holly Roe-Johnson, DVM, Hosmer Veterinary Clinic, reviews a variety of factors when putting together a deworming protocol for her customers in north-central South Dakota. “We look at the age of the cattle, if they are nursing calves, if they are yearling heifers headed to the feedlot or joining the cow herd, their past deworming history, and the time of year,” she said.

Dr. Roe-Johnson recommends a long-acting dewormer for producers who are putting calves out to pasture in the spring, regardless of whether they’ll be selling or retaining them. “When you pencil it out, it is more affordable to use the extended-release dewormer instead of a traditional injectable for the grazing season,” she stressed. “The cost of using the extended-release dewormer is far less than the time and labor needed to run cattle in every 30 days for another dose.”

Internal parasites have a negative impact on weight gain, milk production, reproductive efficiency and carcass quality.1 Deworming those developing heifers has been shown to improve growth, hasten the onset of puberty, and improve first-breeding pregnancy rates.2,3,4

“A good deworming program can make a world of difference,” Dr. Wade confirmed. “We’ve seen increased response to vaccines, improved appetites and higher conception rates for heifers without heavy parasite loads.”

One study showed that heifers treated with an extended-release dewormer had heavier body weight, greater weight gain and greater average daily gain than those treated with a conventional, shorter-duration dewormer.5 In the same study, a greater proportion of extended-release-dewormer treated heifers calved in the first 21 days of the subsequent calving season than the conventional dewormer group.5 “There was about a 22% higher rate of pregnancy,” Dr. Wade explained. “It’s incredible.”

The science behind how an extended-release dewormer works lies with a technology that allows a single treatment to last up to 150 days, long enough to break the parasite life cycle and effectively reduce parasite burdens on the pasture:

  1. After the initial subcutaneous injection, the drug concentration reaches a high peak to control parasites right away.

  2. Extended-release technology enables the remaining drug concentration to encapsulate into a gel matrix. This matrix continues to release the dewormer above therapeutic levels in the animal.

  3. The matrix breaks down approximately 70–100 days after the initial treatment, and releases a second peak. After 150 days, the drug is eliminated from the body.

“The value of the technology is in the pounds of beef we’re producing and the pregnancies we’re creating,” Dr. Wade concluded. “With spring parasite season around the corner, it’s a good time to talk with your veterinarian about your deworming goals, and discuss if an extended-release dewormer is the right fit.”


1 Hawkins JA. Economic benefits of parasite control in cattle. Vet Parasitol 1993;46(1–4):159–173.

2 Stromberg BE, Vatthauer RJ, Schlotthauer JC, et al. Production responses following strategic parasite control in a beef cow/calf herd. Vet Parasitol


3 Hersom MJ, Myer RO, Carter JN. Influence on weaning weights of nursing beef cattle calves dewormed 90 days prior to weaning. Livestock Sci 2011;136


4 Clark CA, Busby WD, Gunn PJ. Effects of internal parasite infection at feedlot arrival on performance and carcass characteristics of beef steers.

Appl Anim Sci 2015;31(5):412–416.

5 Andresen CE, Loy DD, Brick TA, Gunn PJ. Case Study: Effects of extended-release eprinomectin on cow-calf performance and reproductive success in a fall-calving beef herd. Prof Anim Sci 2018;34(2):223–229. https//

©2024 Boehringer Ingelheim Animal Health USA Inc., Duluth, GA. All Rights Reserved. US-BOV-0453-2023

Subscribe to Our Newsletters
BEEF Magazine is the source for beef production, management and market news.

You May Also Like