🐴 Blue Light Masks Help Brood Mares Cycle Early Without Stalling in 2025 💡🧬

By Dr Duncan Houston BVSc

Breeders aiming for foals born as close as possible to January 1 know the challenge of getting mares to cycle early. In the northern hemisphere, mares are seasonally polyestrus—they cycle only during months with increasing daylight, typically from March to October. So how do we get mares to cycle—and breed—in the middle of winter? In 2025, one of the most innovative answers is the use of blue light masks. 🧠🐎

📅 Why Early Foals Matter

For breed registries and competitions, most horses have an official birthdate of January 1—regardless of the actual foaling day. A foal born in January has a clear advantage over one born in April or May when competing as a yearling or two-year-old. ⏳

• 🏇 Older foals = greater physical maturity
• 💪 Early foals = better chances in show and performance disciplines

That’s why many breeders aim to have mares conceive as early as February. 🌱

🧠 How Light Controls Reproduction

Mares are stimulated to cycle by increasing daylight. This is because light suppresses melatonin, which in turn triggers reproductive hormone activity. 📈

Without enough light, the reproductive system remains in winter dormancy. The solution? Extend the photoperiod artificially. 💡

🛠️ Traditional Light Therapy

The most common method to induce early cycling involves:

• 🏠 Stabling mares at dusk (around 5–6 p.m.)
• 💡 Keeping barn lights on until 10–11 p.m. to achieve 16 hours of light
• 📆 Starting December 1 and continuing for 60+ days

This approach is effective—but it has downsides:

• 🧽 Increased labor for stalling and cleaning
• 💥 Higher risk of colic in confined horses
• 🌾 Reduced mental wellness compared to pasture life

💡 Blue Light Masks: A Modern Alternative

Dr. Barbara Murphy of Ireland developed a wearable blue light-producing face mask that provides the same hormonal stimulation as full-barn lighting. These masks:

• 🔷 Emit short-wavelength blue light over one eye
• 🌙 Automatically activate after dusk
• 🧠 Trick the mare’s brain into sensing longer days

This means mares can stay on pasture while receiving reproductive light stimulation. 🧬

✅ Advantages of Blue Light Masks

• 🌿 Mares stay outdoors in a more natural setting
• 🛏️ Less risk of stabling-associated colic
• 🔋 Lower labor and electricity costs
• 📈 Higher conception rates earlier in the season

🧪 When to Start Using the Mask

The goal is to start blue light exposure by December 1—mimicking the increasing day length of spring. The mare should wear the mask:

• 📆 16 hours/day total light exposure
• 🛏️ For at least 60 days before breeding

Mares usually begin cycling by mid-February if they’ve received consistent light exposure. 🎯

📋 Important Considerations

• 🧠 Only one eye needs light exposure to affect melatonin levels
• 🔄 Masks should be fitted properly and worn consistently
• 🔋 Ensure the battery is working and check light output daily

Some mares may also benefit from hormonal support (e.g., progesterone therapy) if they don't cycle as expected. 💊

📲 Ask A Vet for Breeding Prep Support

If you're planning for early foals and want to keep mares on pasture, visit AskAVet.com or use the Ask A Vet App for custom light program planning and breeding strategies. 📱🐴

Dr Duncan Houston and the team can help select the right mask system, time hormone treatments, and monitor cycling progress for your broodmares. 🧬💬

🏁 Final Thoughts

In 2025, artificial light no longer requires artificial housing. Blue light masks offer a safe, smart, and science-backed way to stimulate early cycling while preserving your mares’ natural lifestyle. Earlier foals, happier horses—without the barn stalls. 💡🐎

Want early pregnancies without stalling? Visit AskAVet.com to learn more about blue light breeding plans 🐴💡