How do you tell if a mare has ovulated?

Indications of impending ovulation in the mare

1. Follicular diameter must be determined by averaging the widest and narrowest parts visible per ultrasound.
2. Most mares are less likely to ovulate with a follicle that is smaller than 35 mm;

How long after LH surge is egg?

The brain then produces a surge of luteinizing hormone (LH), triggering ovulation. The release of the egg from the follicle and ovary happens about 24 hours later (10–12 hours after LH peaks) (13, 17).

What does LH do in horses?

The primary function of LH is formation of the corpus luteum. As GnRH levels increase, the pituitary gland is prompted to secrete LH. In the mare, LH is instrumental in triggering ovulation, as well as converting the follicle into a corpus luteum.

How do I know my LH surge?

How to detect your LH surge. For many women, it’s easy to detect their LH surge using ovulation predictor kits (OPKs). These are readily available online and in most pharmacies. These kits are similar to pregnancy tests because they measure hormone levels in your urine.

When should you inseminate a mare?

The optimal time for AI using chilled semen is within 24 hours before expected ovulation. The insemination should be repeated after 48 hours if the mare has not ovulated. When frozen semen is used, every attempt should be made to inseminate the mare within 12 hours before ovulation or within 6 hours after ovulation.

What do you give a mare to ovulate?

HCG is approved and licensed for use in veterinary practice for inducing ovulation in mares. For several years, hCG has been used effectively in inducing ovulation in mares that are in behavioral estrus with a follicle of 35 mm or greater.

What is the success rate of artificial insemination in horses?

Table I

Why does the Jockey Club not allow artificial insemination?

The Jockey Club has never allowed artificial insemination, or AI. Vials of frozen sperm are easier to transport and dilute and can impregnate more mares than live cover, so AI could produce a glut of thoroughbreds born from popular studs and mares.

What do you give a mare to bring her into heat?

There are a variety of hormonal therapies available to the equine practitioner to help bring mares into estrus and hasten ovulation. They include human chorionic gonadotropin (hCG), various progestin/estradiol combinations, gonadotropin releasing hormone (GnRH) analogs, and dopamine antagonists.

When does the LH peak in a mare?

A LH surge occurs for several days, with levels of LH reaching their peak after ovulation. The LH level at the time of LH peak is lower than most other species. The unique anatomical structure of the ovaries of mares is known to limit the number of eggs ovulated.

Why do horses secrete so much LH during estrus?

The prolonged secretion of LH during estrus, and the apparent tolerance to continuous or high-dose Gonadotropin releasing hormone (GnRH) administration suggest that regulatory mechanisms in horses differ from regulation of LH synthesis and secretion in other species.

When to start artificial insemination after LH surge?

For most natural matings or artificial inseminations with fresh semen, breeding should begin 2-3 days after the LH surge, and continue every 2 or 3 days until the end of the calculated fertile period.

How are horses tolerant to continuous GnRH stimulation?

Horses are tolerant to continuous GnRH stimulation, which raises the question of how the GnRH receptor can tolerate continuous ligand stimulation without undergoing cell response attenuation. The purpose of the project is to undertand how the equine GnRH receptor can tolerate continuous ligand stimulation without undergoing response attenuation.