The Cost of Purulent Vaginal Discharge (PVD) or Dirty Cows

Why Do We Check Fresh Cows at Herd Health?

Reproductive performance is one of the most significant drivers of profitability in dairy herds. Recent research continues to highlight the hidden economic drain of purulent vaginal discharge (PVD), a common postpartum uterine disorder, and its financial impact within just one lactation cycle.

PVD refers to pus-containing vaginal discharge observed in cows, typically 21 to 60 days postpartum. It indicates underlying uterine infection (clinical endometritis), often without systemic illness, making it easy to miss unless herds are monitored closely. Discharge can sometimes be seen on the tail making it easy to diagnose, but often the discharge or infection is hidden and can only be detected with more invasive diagnostic procedures, such as ultrasounding the reproductive tract, vaginoscopes (those glass tubes we insert into the vagina and look in with a flashlight), or the Metricheck device.

Cows with PVD are:

• Less likely to conceive at first service

• Delayed in returning to estrus cycles

• At higher risk for culling due to reproductive failure

Economic studies show that each case of PVD can result in:

• 5 to 10 fewer milk-producing days in the following lactation

• An estimated $200 to $400 CAD in lost income per affected cow

• Increased insemination costs

• Elevated culling rates, impacting replacement heifer strategies

Bottom Line – Impact Per Lactation

• Decreased milk yield potential due to reproductive delays

• More days open = higher feed costs without milk income

• Elevated veterinary and reproductive management expenses

• Long-term herd productivity loss if cases are not identified and treated early

• Focus on transition cow management to reduce risk factors (metritis, retained placenta)

Investing in reproductive health pays off — PVD may seem minor, but the lost milk and added costs can erode profitability quickly. Stay proactive, protect your margins.

Best Practices For Your Herd

• Regular post-calving reproductive exams (ideally 28–50 DIM) to detect discharge early. Studies estimate the prevalence of PVD in lactating dairy cows is approximately 20 %, with ranges varying from 5% to over 30% in some herds

• Prompt veterinary treatment where PVD is confirmed.  Usually involves infusion with products like Metricure and cycling the cow with prostaglandin injection ( Lutlayse,  Estrumate Estroplan, Bioestrovet ). Other studies have shown that most of these treatments are not beneficial to measurable economic outcomes such as days to first service and conception rate at first breeding if given prior to 26-28 DIM which is why we don’t check them sooner after calving.

Contact your herd health veterinarian for protocols tailored to your operation.