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Mastitis treatment: Extended therapy gives more flexibility

Bradley Mills Published on 18 April 2014

There is no one-size-fits-all approach to mastitis treatment. With numerous mastitis-causing pathogens lurking on dairies, producers and veterinarians need flexible mastitis treatment options to effectively treat mastitis.

Extended therapy is a relatively new treatment option in the last decade that offers flexibility.



Products specifically labeled for extended therapy give producers and veterinarians the option to treat mastitis infections with the appropriate antibiotic for as little as two days or deliver extended therapy for up to eight days, depending on the infection severity.

What does flexible mastitis therapy offer?
Adhering to on-label, prescribed mastitis therapies is increasingly important to protect the health and well-being of your herd, as well as the dairy.

The flexibility of extended therapy protocols allow you to effectively treat mastitis immediately, and it helps improve the chances of achieving bacteriological cure rates. This means it not only knocks out physical mastitis symptoms but digs deeper to eliminate mastitis-causing bacteria.

Cases that reach only a clinical cure allow the bacteria to remain, creating the potential for chronically infected cows that can relapse or pass the bacteria on to herdmates, which only compounds the problem. Reducing the chance of relapse and chronic infections helps control re-treatment costs and productivity.

Treatment flexibility with extended therapy is especially important because realistically most dairies lack a robust culturing program and don’t always know which mastitis-causing pathogens they are confronting at initial treatment.


Only 42.6 percent of all dairies have cultured individual cows at one time, according to the USDA’s National Animal Health Monitoring System, and research by Dr. Sarah Wagner of North Dakota State University indicates 32 percent of Midwest farms that purchased on-farm bacteriological culture systems discontinued milk culturing after only 2.5 years.

In other words, most dairies are operating without information or from outdated records that don’t accurately reflect the mastitis cases on their operation today. The flexibility of extended therapy helps producers get the jump on mastitis infections while they obtain culture results to further assess treatment options.

Positive outcomes against gram-negative infections
Recent research shows outstanding success when using extended therapy protocols against gram-negative mastitis. The prevalence of gram-negative bacteria remains a threat to herd productivity and udder health.

Nearly 40 percent of all mastitis infections on dairy operations are caused by gram-negative bacteria such as Escherichia coli (E. coli). If left untreated, mild and moderate gram-negative mastitis can become severe and toxic, reducing herd productivity and a dairy’s bottom line.

Old-school thinking about mastitis therapies no longer applies in this new paradigm. Gram-negative mastitis treatment can be successful using extended therapy.

Cornell University research published in the Journal of Dairy Science shows that five-day intramammary extended therapy can effectively treat mild or moderate gram-negative mastitis in which there are visible signs of mastitis but the cow is not sick or off feed.


For clinical mastitis caused by E. coli, 89 percent of the cows treated with a five-day extended therapy regimen showed bacteriological – or complete – cures, compared with 53 percent of untreated control cows, the research shows.

Don’t confuse extended therapy with extra-label
There are only two products with flexible labels on the market that provide the benefits associated with extended therapy, and both require prescriptions along with a valid veterinary-client-patient-relationship (VCPR).

Keep in mind that extended therapy is not synonymous for extra-label. Some producers think that if their two-tube-per-day mastitis treatment doesn’t clear up the infection, they can continue treating that cow.

This is extra-label use of the product, beyond its labeled and intended use. Extra-label use is not advised by veterinarians, and intentional misuse of products puts the dairy at greater risk for residue violations.

Manage mastitis risk and treatment
Milkers and parlor employees are the first line of defense against mastitis infections. What they observe during milking can impact the success of the dairy’s mastitis management program. Train milkers to forestrip and identify mastitis infections so the appropriate treatment protocols can be implemented.

Implement a scoring system such as the 3-2-1 Mastitis Scoring System, which is endorsed by the Milk Quality and Udder Health Committee of the American Association of Bovine Practitioners.

Classifying clinical cases is only one part of disease identification. The best chance of a complete cure depends on early identification of infections. As soon as employees spot signs of infection in the udder, early and aggressive treatment with the proper product for the right duration helps reduce the likelihood of a more severe infection.

Don’t fall victim to the one-size-fits-all mastitis treatment approach. Consult your veterinarian when treating mastitis infections. Veterinarians are the most knowledgeable animal health experts and can offer the best advice on mastitis management and effective treatment options.

Visit the Zoetis website to learn more about mastitis management and extended therapy treatment protocols. PD

Bradley Mills is a veterinarian with Zoetis. Contact him by email .

References omitted due to space but are available upon request. Click here to email an editor.

bradley mills

Bradley Mills

Cost of a cure

Determining the true cost of a mastitis cure requires more than just comparing the price per box of mastitis tubes. Consider these factors when weighing treatment options:

Treatment efficacy
When looking at treatment efficacy, producers need to know whether the product really works. Is it clearing up the milk and eliminating mastitis-causing pathogens? If not, producers will see higher rates of relapse and higher somatic cell counts.

Cost of treatment per day
Producers are often misled by the per-box cost of mastitis tubes. What they often overlook is the number of treatments per box and the frequency of treatment – every 12 hours or every 24 hours.

Cost of milk discard
Read the product label for milk discard. Shorter milk withdrawal periods are often more economical because producers are able to resume putting milk back in the bulk tank sooner.

Potential for residue risk
Managing products with high-residue risk profiles can compromise operation efficiency. It also can increase the potential for shipping adulterated milk. Choose efficacious products with low-residue risk profiles.

Relapse rate and somatic cell count
Producers need to monitor treatment success to make sure they’re seeing high bacteriological cure rates, lower relapse rates and lower somatic cell counts. It’s the only way for producers to know whether treatment is working.