Is there any risk to put a stallion in with pregnant mares over winter?

There are several potential risks associated with putting a stallion in with pregnant mares over winter, including:

- Injury to the mares. A stallion can be very aggressive towards pregnant mares, especially if he is not used to being around them. He may kick, bite, or otherwise injure the mares, which can lead to miscarriage or other complications.

- Injury to the stallion. Pregnant mares can also be dangerous to stallions. They may kick, bite, or trample the stallion, which can cause serious injuries.

- Stress. The presence of a stallion can be very stressful for pregnant mares. This stress can lead to a number of health problems, including weight loss, decreased milk production, and increased susceptibility to disease.

- Breeding. If the stallion is fertile, he may breed the pregnant mares, which can result in unwanted pregnancies.

For these reasons, it is generally not recommended to put a stallion in with pregnant mares over winter. If it is necessary to do so, it is important to take precautions to minimize the risks, such as:

- Introducing the stallion to the mares gradually. This will help the mares to get used to the stallion and reduce the risk of aggression.

- Providing plenty of space. The stallion and mares should have plenty of room to move around so they can avoid each other if necessary.

- Monitoring the animals closely. The stallion and mares should be monitored closely for signs of aggression or stress. If any problems arise, the stallion should be removed from the pasture.