When it comes to treating mastitis, the dairy industry has learned a lot in the last few years. However, despite the advances in knowledge, producers still fall into the trap of believing old myths, says Ron Erskine, veterinarian in the Large Animal Clinic at Michigan State University.

These crutch-like myths offer some producers justification as to why treatment doesn't work, or why milk quality goals have gone unmet. It doesn't have to be that way. Stop believing in old lore and start making progress on mastitis treatment and control.

Following is a list of Erskine's top 10 myths, and reasons why you shouldn't believe them.

Myth #1: Once a Staph aureus cow, always a Staph aureus cow.

Although it can be difficult to cure, intramammary infections caused by Staph aureus are not incurable. Depending on the herd, 30 percent to 70 percent of infected quarters can be cured during the dry period. Use culture and susceptibility screening to help select the drug with the best chance of killing the pathogen present.

Myth #2: It doesn't pay to treat clinical mastitis. Or, conversely, all clinical cases should be treated.

All treatment decisions hinge on the severity of the case, the history of the affected cow, and the bug causing the mastitis. For example, the use of antimicrobial therapy in clinical mastitis caused by coliform bacteria is questionable. However, if the culprit is staphylococci or streptococci, the cow will more than likely benefit from treatment. Although many herds have reduced their use of antimicrobial therapy for clinical mastitis, don't assume that this approach is the right approach in all cases. You must know which bugs are present to develop effective treatment protocols - in terms of cure and cost.

Myth #3: Oxytocin and stripping is the best way to treat.

Although a popular method of mastitis treatment, frequent stripping of the quarter is not beneficial in all cases. For example, when the milk is watery and discolored, frequent stripping may actually be harmful. However, if cows have clots or flakes that could plug the teat canal, then stripping is beneficial.

Myth #4: Treat all clinical cases until milk returns to normal.

In some cases, milk does not return to normal. For example, with coliform mastitis, after the infection clears the cow may stop milking in that quarter instead of resuming the production of normal-looking milk. Non-responsive quarters also can be a sign of a resistant organism such as yeast and Pseudomonas. If your milk-discard period averages greater than five days, you need to review and re-evaluate treatment protocols.

Myth #5: Commercial infusion tubes are not as good today as
25 years ago.

It may seem that cure rates today are less than they were 25 years ago. However, it is not the cure rate that has changed - it is the definition of a "cure" that has changed. And, when the results aren't as favorable as you like, don't blame the drugs necessarily, but look for breakdowns in your protocols for administering the drugs. Drugs work when used correctly.

Myth #6: A double dose of tubes is better.

While two scoops of ice cream may be better on a cone than one, the same does not hold true with antibiotic infusion tubes. The key for achieving cure is not getting the highest dose possible, but rather exposing bacteria to the proper dose length.

Myth #7: Extra-label products are more effective.

Many studies have shown that extra-label treatments for mastitis have little positive effect, as compared to the cure rates achieved by commercially available products labeled for mastitis treatment.

Myth #8: Switch antibiotics if clots and flakes remain after two treatments.

The key to successful therapy is staying with the same drug as long as possible. Switching drugs mid treatment starts the therapeutic clock - the time needed to achieve a cure - all over again and can lead to bacterial resistance.

Myth #9: First-generation cephalosporins and synthetic penicillins are more effective treatments because they work against gram-positive pathogens and coliforms.

No drug holds a magic cure for treating all cases of clinical mastitis. Instead, when making treatment decisions, you first must rate the case as "mild" or "severe," and then identify which pathogens are present. Use that information to help guide your treatment decision. Work with your veterinarian to determine which pathogens commonly occur on your farm, and then develop treatment protocols that will be most effective.

Myth #10: My mastitis therapy program is doing fine even though I don't keep records.

This is the most critical problem in herds today. Without knowing which bugs infect your herd, the clinical outcome of past cases and herd risk factors for clinical mastitis, it is impossible to know if you have a good therapy plan.