How Far Out From Foaling Do Mares Start Making A Bag?

Last Updated on June 1, 2022

If you’ve got a mare due to foal, you’ll want to know how far out from foaling do mares start making a bag, as well as all the other signs of labor in horses. Let’s find out everything you need to know about mares and foaling!

How Far Out From Foaling Do Mares Start Making A Bag?

It can be very difficult to predict when a mare is going to foal, particularly in maiden mares that have never had a foal before. The gestation period of a horse can vary broadly, from 320 to 380 days. It is vital to monitor a mare closely once she reaches 320 days, as there are some tell-tale signs that will indicate that she is due to give birth soon.

One of the key areas to monitor closely is the udder of your broodmare. If you’re not sure where your mare’s udder is, look between her hind legs, and you will see two mounds of flesh with a teat on each one. Don’t be surprised if you’ve never noticed them before, as when a mare is not lactating they are barely visible!

As the birth becomes imminent, the mare will start to ‘bag up’ – this means that she is developing mammary tissue that will enable her to produce milk. The udders will look larger and more distended, as they gradually fill with milk.

But how far out from foaling do mares start making a bag? Well, this does vary from mare to mare, but the normal time frame is around two to four weeks before foaling. In maiden mares that have never had a foal before, this length of time may be shorter.

Around four to six days before foaling, the udders will start to fill with milk much more quickly, making them appear engorged and swollen. Once your mare’s udders feel full and solid, it is highly likely that she is going to foal soon!

Read more about:

What Is High Hind End Lameness In Horses?

Can A Mare Abort One Twin?

How Long Before Foaling Does A Mare Wax Up?

Waxing up is one of the most reliable indicators that a mare is due to foal, and when this occurs you will need to check the mare much more frequently through the day and night.

When a mare waxes up, a waxy secretion builds up on the teats. This is fairly easy to spot and is very helpful if you are not sure when your mare is going to foal. Waxing up will normally appear around three days before foaling.

However, like most things when it comes to horses, waxing up is not 100% certainty! Some mares do not wax-up at all, so you will need to observe closely for any other signs of foaling.

Foaling: Brood Mare and Foal Management

How Long Can A Mare Run Milk Before Foaling?

Some mares will start to leak milk from the udders prior to foaling, particularly in the final few hours before the birth of the foal. This is not always a problem, but something that you need to monitor closely. You might see an occasional drip of milk from the udders, or even a constant stream if foaling is imminent.

When a mare gives birth, she produces two different types of milk in the udders. The first lot of milk to be produced is called colostrum – this is thick, yellow, and packed full of vital antibodies. Once the foal has consumed this life-saving colostrum, the mare then produces protein-rich milk for the foal to drink.

When a mare starts to run milk before foaling, there is a chance that all the colostrum could be lost before the foal is born. If a mare runs milk for more than 24 hours, veterinary advice should be sought to identify if she is having any problems. It may also be necessary to milk the mare to obtain the colostrum, ready to feed to the foal by bottle when it is born.

If all the colostrum is leaked from the udders, the foal will not obtain vital antibodies and will be at high risk of infection and disease. Foals that do not receive colostrum within the first 12 hours of life normally need a transfusion of antibody-rich plasma to boost their immunity.

How Long Can A Mare Run Milk Before Foaling

Summary – How Far Out From Foaling Do Mares Start Making A Bag?

So, as we have learned, how far out from foaling do mares start making a bag can vary from mare to mare, but it is normally between two and four weeks before foaling. Maiden mares tend to bag up much closer to foaling than more experienced mares. In the last few days before foaling, the udder will fill with milk and appear more engorged and swollen.

We’d love to hear your thoughts on how far out from foaling do mares start making a bag! Are you eagerly awaiting your new foal and starting to notice some milk in your mare’s udder? Or maybe you’ve got some questions about how to care for a mare that is due to foal? Leave a comment below and we’ll get back to you!


What Are The Signs Of A Horse Going Into Labor?

When a mare is going into labor, she may become restless and appear uncomfortable. Signs include kicking at the belly, pacing, frequent urination, and sweating. These signs all indicate that she is going into the first stage of labor.

What Does A Mare Bag Look Like Before Foaling?

Before foaling, the bag - or udder - of a mare will be firm and distended. This is because it is full of colostrum, the antibody-rich first milk that needs to be consumed by the foal within 12 hours of birth.

Can A Maiden Mare Foal Without Bagging Up?

Maiden mares are much more likely to foal without bagging up than a more experienced broodmare. When a mare foals for the first time, it can be very difficult to predict when she is going to foal, and the process normally involves many nights and days of close observation.

What Causes Red Bag Foaling?

In  a red bag foaling, the placenta has started to separate from the lining of the uterus prematurely. The most common causes of this foaling emergency are stress, fescue toxicity, placental infections, and placentitis.