You don’t have to be a professional gambler to understand these odds — as many as one in two of your cows may be affected by subclinical endometritis.

Subclinical endometritis, an inflammation of the endometrium or uterine lining, affects 35 to 50 percent of cows between 35 to 60 days in milk, says Carlos Risco, University of

Florida veterinarian and professor of theriogenology.

The challenge with subclinical endometritis is that it is not detectable by rectal palpation, and no vaginal discharge is evident. Uterine cultures may or may not verify bacterial infection.

Accurate diagnosis depends on laboratory cytology (cellular) analysis using uterine lavage.

Even more difficult, there are no good treatments for subclinical endometritis, says Risco. “You must prevent it.”

Here are four ways to prevent subclinical endometritis on your dairy.

1. Optimize pre-calving immunity

Your goal is to optimize the immune function of transition cows. And that begins with
proper nutrition.

Rations should include adequate levels of calcium, selenium and vitamins A and E. Work with your nutritionist to ensure that rations are highly palatable and properly balanced for cows in the early transition phase that begins about three weeks prior to calving. “You want to stimulate the cows’ appetites so that they maintain dry matter intake to prevent subclinical ketosis which affects immune function,” says Risco.

Evaluate bunk space for these cows. They need at least 24 inches per cow.

Also, begin the transition phase with the cow in good physical shape. Over-conditioned cows, those with a body condition score (BCS) greater than 4 on a 5-point scale, often exhibit a higher incidence of uterine infection that can morph into subclinical endometritis. Likewise, under-conditioned cows, those with a BCS of 2.5 or less, are even more likely to develop an infection, says Michael O’Conner, extension dairy specialist at PennStateUniversity.

Therefore, monitor body condition scores in late lactation and during transition so that cows calve with a BCS about 3.5.

Additionally, uterine infections may result from systemic infections elsewhere in a cow’s body associated with other diseases. Make sure your vaccination protocol is current and properly administered. Be sure to include protection against diseases like bovine rhinotracheitis, bovine viral diarrhea and leptospirosis, suggest experts at the University of Maryland.

2. Keep calving pens clean

Cows also need a clean pen in which to calve. Pay attention to sanitation before, during and after calving.

Make sure that you have areas specifically reserved for calving, and that calving-pen bedding is changed frequently. Straw bedding is the preferred medium. Do not permit cows to give birth in manure-laden facilities.

Maternity areas should also be well-ventilated. Dairy specialists at PennStateUniversity suggest that you increase maternity area ventilation during hot, humid conditions if possible.

For example, add fans so that they provide 800 to 1,000 cubic foot per minute of airflow per cow. Also, clean dry cow and calving pens more often, and reduce stocking density in these areas during summer months.

3. Train maternity area employees

Any assistance or manipulation during calving can easily introduce unwanted microorganisms into the uterine tract. Develop assistance protocols and make sure that everyone follows them. Involve your veterinarian in the development and instruction of these protocols.

First, train employees on proper calving procedures. A photographic library of bovine obstetrics and other reproductive data is available by following this link.

Make sure that maternity-pen personnel know when and how to assist with dystocia births, as well as how to address milk fever and ketosis cases.

And be sure to train employees to use hygienic practices when assisting cows during calving. For example, instruct them to thoroughly wash the perineal region with disinfectant, soap and water before offering assistance. Also make sure obstetrical chains or other equipment are disinfected. Use disposable plastic sleeves to further prevent the introduction of infectious organisms.

4. Monitor fresh cows

Despite these efforts, uterine infections will still affect some cows as they move into early lactation.

Beware of too many pen moves.

If your facilities and personnel skills permit, institute a daily fresh-cow monitoring program that checks for cow attitude, temperature and physical signs of infections. Use more than one parameter to ensure that you’re getting the full health picture. Again, work with employees so they know what to look for and how to address sick cows.

Also track milk production. You should see a consistent increase in daily milk production for healthy cows.

If you cannot monitor cows daily, be sure to observe them on days four, seven and 10 post-calving. “These seem to be critical days,” says Risco. 

Identify any early-post partum cows with uterine infections and treat them right away to help prevent subclinical endometritis. These are cows with a fever of 103 degrees F, dullness in appearance and brownish, fetid discharge during the first week to two weeks post-calving.

Standard treatments are somewhat controversial, so work with your veterinarian to develop a treatment plan for your operation. Prostaglandin therapy in early postpartum has shown some success and may be worth your consideration.

Finally, work with your nutritionist to make sure that the rations provide proper energy levels, as well as proper vitamin and mineral supplementation. And that intakes continue to climb after calving.