How Long Are Donkeys Pregnant?

A donkey pregnancy lasts about a year, longer than a horse's, and the due date is hard to pin down. Most donkeys kept as companions are never bred, but if a female has been with an uncastrated male, it's worth knowing what the timeline looks like.

About 370 days

Two veterinary studies give very similar averages. A 2015 study of Martina Franca donkeys in Theriogenology found an average pregnancy of about 371 days, with longer pregnancies when the foal was male. A 2019 study in the same journal found an average of 370.8 days (± 16.6 days) for full-term pregnancies, and that the season of conception didn't change the length.

That spread matters: with a standard deviation of more than two weeks, plenty of healthy pregnancies run well either side of the average. The breeding due date calculator gives the likely date and a window around it.

Caring for a pregnant donkey

• Feeding: The Donkey Sanctuary's handbook says pregnant and nursing donkeys should get ad-lib hay or haylage in the last third of pregnancy and the first three months of nursing, more than the straw-heavy diet of other donkeys.
• Health risks: being pregnant or nursing is on the Sanctuary's list of things that raise a donkey's risk of hyperlipaemia, and pregnancy is one of the causes of laminitis.
• Your vet: plan the pregnancy and the birth with a vet who knows donkeys.

Avoiding unplanned foals

The Donkey Sanctuary recommends castrating colts between 6 and 18 months old, as young as possible within that range, and keeping older castrated males separate from females for at least two months afterwards.

Sources: Carluccio et al., “Factors affecting pregnancy length and phases of parturition in Martina Franca jennies”, Theriogenology (2015); Nervo et al., “Field ultrasound evaluation of some gestational parameters in jennies”, Theriogenology (2019); The Donkey Sanctuary, Donkey Care Handbook. Sources checked: October 2026. Breeding needs a vet's input; this is general information.

Common questions

How long is a donkey pregnant?

About a year. Two veterinary studies found averages of about 371 days and 370.8 days, a little longer than a horse's pregnancy.

How much does a donkey's due date vary?

Quite a lot. In one study the standard deviation was 16.6 days, so many healthy pregnancies end two or more weeks either side of the average.

What does a pregnant donkey need?

The Donkey Sanctuary's handbook says pregnant and nursing donkeys should get ad-lib hay or haylage in the last third of pregnancy and the first three months of nursing. Pregnancy also raises the risk of hyperlipaemia and can cause laminitis, so involve your vet.

When should male donkeys be castrated?

The Donkey Sanctuary recommends castrating colts between 6 and 18 months old, as young as possible within that range, and keeping older castrated males away from females for at least two months afterwards.