Over the years, there has been controversy about treating mild and moderate cases of clinical mastitis caused by E. coli, says Pamela Ruegg, extension milk quality veterinarian with the University of Wisconsin-Madison.

“I often get the question: ‘Do these cases of clinical mastitis actually require antibiotic therapy?’” Ruegg says.

In a recent YouTube video, Ruegg shares some questions to consider when making a decision to treat E. coli mastitis:

• First, do you have a culture result that indicates the case is E. coli? “We can’t recognize E. coli simply by looking at the symptoms in the cow,” Ruegg says.

• If you know it is E. coli, then the next step is to look at the characteristics of the cow:

• Is this the cow’s first case of clinical mastitis in this lactation?

• Is this an otherwise healthy cow?

• Has the somatic cell count of the cow generally been less than 200,000 cells per mL?

If the answer is “yes”, then antibiotic treatment is often not necessary. The treatment can be called “watchful waiting,” Ruegg says. “Watch the cow, discard the milk and the milk should return to normal within four to six days.”

If the answer to the above questions is no, then you might want to consider the use of antibiotic treatments in these types of cows.