Pregnancy Loss and Abortion in Donkeys

Pregnancy loss means a jenny loses the pregnancy before a live foal is delivered. In equids, losses may happen very early, before a pregnancy is obvious, or later in gestation as abortion, stillbirth, or premature delivery of a weak foal. Donkeys share many reproductive risks with horses, so vets often use equine abortion guidelines when working up a donkey pregnancy loss.

Late-term abortion in equids is often tied to placental disease, especially placentitis, which interferes with oxygen and nutrient delivery to the fetus. Infectious causes can include equine herpesviruses, equine viral arteritis, leptospirosis, bacterial infections, and fungal infections. Noninfectious causes can include twins, poor maternal health, trauma, toxins, or fetal abnormalities.

For pet parents, the hardest part is that some jennies show very few warning signs before the loss. Others may develop vulvar discharge, udder enlargement too early, restlessness, or signs of illness. Because some infectious causes can spread to other equids, pregnancy loss should be treated as both a medical and a herd-health concern until your vet says otherwise.

Pregnancy loss in donkeys can be infectious or noninfectious. In equids, important infectious causes include equine herpesvirus, especially EHV-1, equine viral arteritis, leptospirosis, bacterial placentitis, and fungal placentitis. Published donkey cases have also linked abortion to pathogens such as equine herpesvirus 8, Salmonella abortus equi, and Neospora caninum. In many field cases, though, no single cause is confirmed even after testing.

Placentitis is one of the most important causes of late-term pregnancy loss in equids. It can develop when bacteria ascend through the reproductive tract, or less commonly when infection reaches the placenta through the bloodstream. The inflamed placenta cannot support the fetus normally, which can lead to abortion, premature delivery, or a weak newborn.

Noninfectious causes matter too. Twin pregnancy is a well-known cause of abortion in equids because the uterus usually cannot support both fetuses to term. Poor body condition, severe stress, high fever, systemic illness, toxins, trauma, umbilical cord problems, and fetal or chromosomal abnormalities can also contribute. Early pregnancy loss is especially frustrating because the underlying cause often remains unknown.

Because donkeys are often managed alongside horses, mules, or new arrivals, exposure history matters. Recent transport, breeding activity, contact with outside equids, contaminated water, wildlife or rodent exposure, and herd outbreaks of respiratory or reproductive disease can all help your vet narrow the list.

Diagnosis starts with a careful history and exam. Your vet will ask about breeding dates, vaccination status, recent travel, contact with outside equids, illness in the herd, discharge, premature udder development, and whether the jenny has lost pregnancies before. Ultrasound is often used to confirm fetal viability, assess the uterus and placenta, and look for signs that support placentitis or twin pregnancy.

If abortion has already happened, the best diagnostic sample is the whole story: the jenny, the fetus, and the placenta. Your vet may submit the fetus and fetal membranes for gross examination, histopathology, bacterial and fungal culture, and PCR or other testing for viruses such as EHV or equine viral arteritis. For leptospirosis, labs may test placenta, umbilical cord, fetal kidney, or liver with fluorescent antibody or immunohistochemistry. Bloodwork on the jenny may also help assess infection, inflammation, dehydration, or organ stress.

This workup matters for two reasons. First, it may guide treatment for the jenny after the loss, including uterine care, anti-inflammatory support, and monitoring for retained placenta or metritis. Second, it helps protect the rest of the herd by identifying contagious causes and shaping quarantine, vaccination, and breeding decisions.

Even with a thorough workup, some cases stay unexplained. That can be frustrating, but it is common in equine reproduction. Your vet can still use the timing of the loss, exam findings, and herd history to build a practical prevention plan for the next breeding season.

Prevention starts before breeding. Ask your vet to examine the jenny, review body condition, address dental or parasite issues, and discuss reproductive tract health. Early pregnancy checks are important because twin pregnancy is a major noninfectious cause of abortion in equids, and early ultrasound gives your vet the best chance to identify and manage it.

Good herd biosecurity also matters. Pregnant jennies should be separated from equids with fever, nasal discharge, or unknown vaccination status. New arrivals should be quarantined. Shared water sources, wildlife exposure, and rodent contamination can increase infectious disease risk, including leptospirosis in some regions. Clean foaling areas, careful breeding hygiene, and prompt veterinary attention for vulvar discharge or premature udder development can reduce risk.

Vaccination and monitoring plans should be individualized with your vet. In horses, EHV-1 vaccination during pregnancy and management steps to reduce exposure are standard prevention tools, though abortion can still occur despite vaccination. Donkeys often follow similar equine herd-health principles, but your vet should tailor the plan to local disease pressure, breeding method, and herd movement.

If a jenny has had a previous loss, future pregnancies deserve closer watching. Serial ultrasound in late gestation may help detect placental changes in high-risk animals. Early recognition of placentitis or maternal illness gives your vet more options and may improve the chance of carrying the pregnancy longer.