Dealing with cows with metritis may be all too common on some farms. Why is the incidence so high? What causes this disease?
By: Phil Durst, Michigan State University Extension
Metritis and endometritis are diseases of the uterus that will reduce reproductive performance, decrease milk production and increase the risk of early culling. So the financial costs are high. And as with any disease, metritis is associated with pain or discomfort for the animal. Therefore, the animal well-being costs can be high as well.
This is the first in a series of four articles on metritis from Michigan State University Extension. Subsequent articles will focus on detection, prevention and treatment of metritis and endometritis.
From a practical standpoint, we deal with metritis and endometritis as one disease and will refer to them both as metritis. We will distinguish between them for the purpose of treatment. The incidence of metritis is around 20% of lactating dairy cows and similarly around a 20% incidence of clinical endometritis. However, more important than the US prevalence rates of disease is the incidence in your herd and your personal answer to the question, can it be lower?
The uterus is to be a sterile place. Calving generally results in the introduction of bacteria to the uterus. In a cow with a healthy immune response, those infections are usually cleared by a week post-partum without any intervention. What happens the other times?
Disease results when bacteria overwhelm a cow’s immune response. It is like an equation. When the immune system is suppressed, a lower bacterial exposure can result in disease. When bacterial exposure is high, anything that reduces immune responsiveness of the animal may result in disease. Because both sides of the equation are directly or indirectly under the control of the dairy producer, consider the changes you need to make in management to reduce metritis.
Let’s take a look first at factors that increase bacterial exposure at the time of calving:
- Dirty calving area
- Dirty cows
- Contaminated obstetrical tool
- Lack of cleanliness on the part of the personnel assisting calving-
- Poor technique when assisting calving (not fully cleaning the vulva before entering the vagina)
In some ways, these are all shortcuts. Maybe the calving area was not a priority due to the workload somewhere else, or the animal density was higher than usual because of a lot of cows calving around the same time. Maybe we rushed to help a cow that was in distress and didn’t take time to do things right. When we take shortcuts in sanitation and procedures, those shortcuts eventually cause problems.
What about factors that decrease the immune response of an animal? Fresh cow immunosuppression is a normal phenomenon. However, it may be exacerbated by stressors such as:
- Dystocia, twins, retained placenta and stillbirths
- Metabolic disease such as hypocalcemia, ketosis, and left displaced abomasum
- Heat, crowding or movement
- Negative energy balance
- Insufficient intake of key vitamins and nutrients
Disease is unlikely to be caused by a single factor. However, the cumulative effect of stresses on immunity and bacterial load results in disease break.
The answer to metritis/endometritis is to focus on prevention. We will not always be able to prevent it (because of things we cannot control such as twins and stillbirths and gaps in our management of what we can control) but we can reduce it significantly by learning what factors on a farm are conducive to the development of metritis. Those things are farm specific and maybe, season specific.
Start with keeping records of cows and heifers that are diagnosed with metritis or endometritis and add to those records any potential factors that may or may not have been involved. Slowly, a picture will appear that helps define the risk areas for the disease on your farm.
Other articles in this series: