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Veterinary Management of Broodmares (2013)

It is the opinion of the AAEP that the commonly used diagnostic and therapeutic procedures are important in the proper management of broodmares for optimum reproductive efficiency.

These procedures include, but are not limited to: palpation per rectum, ultrasound examination, visual and endoscopic examination of the internal reproductive organs, endometrial culture, endometrial cytology, endometrial biopsy, hormone assays, intrauterine therapy, urogenital surgery, embryo and gamete retrieval, manipulation and transfer, and artificial insemination (AI).

AI should be performed under the direction of a licensed veterinarian pursuant to a valid VCPR. All other above named procedures should only be performed by a licensed veterinarian.

Revised by AAEP board of directors in 2013.

Recommendations for Transported Semen as it Relates to Equine Viral Arteritis (EVA) (1992)

Equine Viral Arteritis (EVA) with respect to stallions from which semen is collected and transported from the premises in the fresh cooled or frozen state:

1. Breeding stallions unvaccinated for EVA should be tested for evidence of equine viral arteritis infection using the serum neutralization test. No stallion should be vaccinated for the first time without its pre-vaccination titer first being established.

2. Seronegative stallions (titers of less than 1:4) should be vaccinated at least 28 days prior to breeding or semen collection and receive an annual booster. Vaccinated stallions should be isolated for 28 days post vaccination. Seronegative stallions that are vaccinated for EVA should be vaccinated at least 28 days prior to breeding or semen collection and receive an annual booster. Vaccinated stallions should be isolated 28 days post vaccination.

3. Seropositive stallion’s (unvaccinated) shedding status should be determined every 12 months either by: Attempted virus isolation on semen or, test breeding to at least two seronegative mares and monitoring for seroconversion at 14 and 28 days post breeding.

4. Seropositive stallions (vaccinated) need not be tested for virus shedding if seronegative prior to initial vaccination.

5. The serologic and shedding status of non-EVA vaccinated seropositive stallions should be made known to mare owners receiving the semen. This information should also be reported to state authorities where so required and to breed associations where so required.

6. Stallions seropositive for EVA from natural exposure need not be vaccinated.

Guidelines pertaining to mares which will be inseminated with transported fresh cooled or frozen semen.

1. Seronegative mares to be inseminated with semen from an equine arteritis virus shedding stallion should be vaccinated against EVA at least 21 days prior to insemination. These vaccinated animals should be isolated for 21 days post vaccination.

2. Mares seropositive for EVA from natural exposure need not be vaccinated.

Reviewed by AAEP board of directors in 2010.

Veterinary Management of the Breeding Stallion (1996)

It is the opinion of the AAEP that proper management of the breeding stallion is paramount in obtaining optimum breeding efficiency. Proper management requires close cooperation between the licensed veterinarian and stallion manager. The licensed veterinarian can contribute various diagnostic and therapeutic procedures to this partnership.

These procedures include, but are not limited to, the following: visual, tactile, endoscopic and sonographic examination of the reproductive organs; collection and evaluation of semen (i.e. assessment of spermatozoal number, initial spermatozoal motility, longevity of spermatozoal motility and spermatozoal morphology); evaluation of spermatozoal responsiveness to cooling and freezing techniques; evaluation of extender compatibility with semen; reproductive tract culture; reproductive tract biopsy; adjunctive diagnostic techniques (e.g. hormonal assays, sperm chromatin structure assay, anti-sperm antibody assay and transmission electronic microscopy); medical therapeutic strategies; and urogenital surgery.

A reproduction examination should be carried out by a licensed veterinarian prior to entry of a stallion into a breeding program and periodically during his breeding career in order to manage the stallion to his maximum efficiency. Semen collections should be performed by a licensed veterinarian or qualified reproductive technician in association with a veterinarian. Diagnostic tests, medical treatments and urogenital surgery should be conducted only by a licensed veterinarian.

Reviewed by AAEP board of directors in 2010.

Recommendations Regarding Equine Viral Arteritis (EVA)

Please visit the Biosecurity Guidelines for Control of Venereally Transmitted Diseases at here

Breeding Terminology (2010)

In providing written reports to interested parties, the AAEP encourages all equine practitioners to use the following terms when conducting reproductive examinations:

Pregnant: Any filly or mare shall be characterized as “pregnant” if and only if a licensed veterinarian has made such a determination. Any such report should include the method of diagnosis (i.e. palpation per rectum, transrectal ultrasound, etc.) and the approximate length of gestation. A statement regarding whether or not the examining veterinarian has determined that the pregnancy appears normal for the gestational age should also be included. Knowledge of any adjunct method(s) used to aid in the maintenance of said pregnancy should be disclosed.

Aborted: Any filly or mare that is not pregnant at the time of examination by a licensed veterinarian should be reported as “aborted” rather than “not pregnant” if the person rendering the report is actually aware that (a) an aborted fetus was observed or (b) the mare had been previously declared “pregnant” based on an examination by a licensed veterinarian at 42 days or more post mating.

Not Pregnant: Any filly or mare that has been examined for pregnancy by a licensed veterinarian, and found not to be pregnant at the time of that examination shall be characterized as “not pregnant” unless there is evidence that the filly or mare has “aborted” as defined above. Any such report shall include the method of determination.

Suitable for Mating: Any filly or mare that is not pregnant shall be characterized as “suitable for mating” if examination by a licensed veterinarian does not reveal any obvious abnormalities that would impair the animal’s ability to have a reasonable chance of becoming pregnant and carrying a foal to term. The examination of the reproductive tract (ovaries, uterus, cervix, vagina, vestibule and perineum) should include palpation per rectum and where practical, transrectal ultrasonography as well as visual and manual examination of the vagina and cervix. While other tests and criteria can be used to further evaluate the animal’s potential fertility, employment of such techniques shall be at the discretion of the examiner or their client. A filly or mare may be characterized as “suitable for mating” based on only one examination even though additional examinations may enhance the likelihood of discovering reproductive abnormalities.

Mating: The physical act of a stallion mounting a filly or mare with intromission of the penis. Artificial insemination qualifies as mating for breeds that permit artificial insemination.

Mated: Any filly or mare that has undergone the physical act of mating but whose pregnancy status has not been determined.

Stillborn: Any foal, after at least 320 days of gestation, that is dead at the time of delivery.

Neonatal Death: Any foal that dies within 14 days of foaling from a medical condition determined to be existing at or dating from birth. 

Foal Died: Any foal that stands and nurses unassisted and subsequently dies from a condition not determined to be existing at or dating from birth.

Revised by AAEP board of directors in 2010.