Conversations: Ask your veterinarian about udder health

Mastitis is the most common and costly disease on dairy farms. Financial losses include lost milk production, treatment costs, discarded milk, reduced quality premiums, labor costs, culled cows and death. Trying to control mastitis is like trying to control the common cold, but a strong management program can keep the number one dairy health issue in check.

Dr. Andy Skidmore is a dairy technical services veterinarian for Intervet/Schering-Plough Animal Health.

By Dr. Andy Skidmore, D.V.M., Ph.D.

The basics of mastitis management can seem like common sense, but often we need a reminder to not be complacent and to look for areas of improvement. As consumers increasingly question how food is produced, mastitis management, udder health and, ultimately, the quality and safety of milk, become larger issues. Challenge yourself to review your mastitis management practices and find ways to improve the quality of the milk you produce.

1) How can I prevent mastitis in my herd?

It is always better to prevent a disease than to treat one, and this is certainly true for mastitis. The milking parlor and the barn are the two primary areas of mastitis prevention. Strict milking procedures and stall and bedding management should be in place and communicated to all employees.

Ask your veterinarian to review your milking procedures and management practices.

2) Is it necessary to treat dry cows?

The dry period and near calving are the times of greatest risk for mastitis, so dry cow treatment is critical to your mastitis prevention program. Use an approved dry cow treatment with broad-spectrum coverage. Following treatment, ensure dry cows have a clean, dry environment, and monitor cows periodically for swollen quarters.

Ask your veterinarian about ways to improve your dry cow mastitis prevention program.

3) How do I diagnose mastitis, particularly subclinical cases?

Early detection increases treatment success, so it’s important to have a comprehensive monitoring program in place. Milkers should be vigilant in watching for clinical signs in the parlor. Subclinical cases are particularly hard to diagnose because there are no visible signs, so it’s important to regularly test individual cows for somatic cell counts.

If your somatic cell counts and/or cases of mastitis increase or are higher than usual, ask your veterinarian to identify areas you may be overlooking to diagnose both clinical and subclinical cases.

4) Should I treat a clinical case if the culture doesn’t grow any bacteria?

Up to one-third of all clinical cases will not grow any bacteria on culture. If bacteria are not present in the udder, then antibiotics won’t help the cow and therefore she should not be treated. The reasons this could happen include: bacteria have either already been eliminated and the gland is still healing, bacteria were never present, something else caused the inflammation or the sample/culture did not represent the true status.

Ask your veterinarian how to manage clinical cases that do not grow bacteria.

5) How does identifying the bacteria help make better treatment decisions?

In the animal health industry we often say, “Know the bug, know the drug.” In treating mastitis, this advice holds true. If possible, culture milk samples to determine if the bacteria is gram positive or negative. Gram negatives, which represent 40% of cases, do not respond well to antibiotic therapy and should not be treated in the mammary gland. Responsible antibiotic use is critical to the image of the dairy industry and the efficiency of animal health programs, so targeted therapy such as this, should be part of your mastitis management protocols. New technologies are being developed to aid producers in mastitis diagnostics.

Work closely with your veterinarian to identify and treat mastitis efficiently and effectively.

6) How do I know that my mastitis treatment is working?

Evaluating your mastitis management program is an important step in the process. Most importantly, watch for visible signs of improvement at milking time, follow label directions of your treatment and be careful not to over-treat your cows. Evaluate changes in somatic cell counts, milk production, discarded milk, recurrence rates, days of withheld milk, days in the sick pen, etc. Keep in mind cows respond differently depending on age of the cow, stage of lactation, season and genetics.

Ask your veterinarian to review and evaluate the effectiveness of your treatment protocols.


Dr. Andy Skidmore is a dairy technical services veterinarian for Intervet/Schering-Plough Animal Health. He lives in upstate New York, and can be contacted by phone: 716-474-2715 or e-mail: