A slight tap knocks the first domino off balance, causing the rest of the dominos to tumble over. A similar situation can cause metritis, a fresh cow health problem which can be triggered by a chain reaction of other health problems in newly-fresh cows.

However, you don't have to sit on the sidelines and watch this domino effect wreak havoc on your cows. By understanding how metritis occurs, you can take action to prevent it. Use the following guidelines to help you prevent metritis.

How it occurs
Metritis occurs when bacteria penetrate the uterine lining and cause an inflammation of the uterine wall. Often times, a retained placenta can act as the "wick" that carries bacteria into the uterus, explains Sam Barringer, a Pfizer Animal Health technical services veterinarian based in Colorado Springs, Colo. That's why metritis is often considered the "sequel" to a retained placenta.

In addition to retained placentas, other fresh cow problems, such as milk fever, dystocia and ketosis, can contribute to an increased incidence of metritis. In fact, a cow is three times more likely to develop metritis if she develops milk fever, a displaced abomasum, ketosis or experiences calving difficulty, says Mark Kinsel, a consulting veterinarian in Nampa, Idaho. Therefore, in order to prevent metritis, look beyond calving to the dry period so that you can prevent some of these problems from occurring in the first place.

Start with dry cow nutrition
If a cow calves with a body condition score of 4.0 or greater on a scale of 1 to 5, she will probably experience more problems than a cow in optimal body condition score at calving - about 3.25 to 3.75. Dystocia, a birth requiring assistance, occurs more often in over-conditioned cows. Dystocia can lead to an increased incidence of retained placentas.
Therefore, in order to prevent these problems, you need to calve cows at optimum body condition. That means managing the protein and energy content of your dry cow and transition cow diets. In addition, pay particular attention to the levels of calcium, phosphorus, potassium and chloride contained in the diets, because an imbalance of these nutrients can lead to milk fever. Likewise, monitor selenium and vitamin E levels to avoid a selenium deficiency - another condition which can cause a retained placenta, and quite possibly, metritis. (Please see "Nutrient recommendations" at right.)

In addition, sound nutrition - especially adequate energy intake - during the dry and transition periods promotes feed intake, says Jesse Goff, veterinarian at the National Animal Disease Center in Ames, Iowa. This is essential to maintaining a proper energy balance and helping the immune system ward off the effects of stress and disease.

The immune system may play a role in the development of a retained placenta, Goff says. Therefore, if the immune system is weakened by stress or disease, it may not recognize the placenta as a foreign object which needs to be expelled from the body, resulting in a retained placenta and possibly metritis.

Minimize stress at calving
If a cow arrives at calving in optimal body condition and has had the benefit of a good transition ration, you must then try to minimize the other stressors which occur at calving.

Number one on your list should be to provide a clean, dry calving area. "It's always hard to beat good sanitation" at calving, Goff says. A clean calving area minimizes the amount of bacteria which may try to invade the uterus.

You'll also want to reduce stress, such as noise and activity around the calving pen, during calving. That means the hospital pen or hoof trimming area shouldn't be next to the maternity pen.

Another common calving stress, dystocia, often results in a retained placenta and metritis. Take steps to minimize calving difficulty before you breed a heifer. Work with your nutritionist and veterinarian to develop nutrition and management practices that allow heifers to calve between 22 and 24 months of age at an appropriate size and weight. In addition, choose sires with good calving-ease scores.

Follow through after calving
The 10 days after calving is an important time to monitor the cow. Run a daily temperature check during this time period, Kinsel suggests. "Catching them early is critical," he adds. To help you identify cows which may fall victim to metritis in early lactation, develop a fresh cow protocol with the help of your veterinarian. (Please see, "A fresh cow protocol" above.)

Besides running a temperature check, monitor dry matter intake and provide oral calcium supplements.

Remember, metritis prevention begins with proper nutrition during the dry period and continues with sound management at calving and shortly thereafter. Use these steps to help you prevent this uterine infection from decreasing your cows' productivity.