Dr. Hartman and the staff at HERC have extensive training and experience in successfully diagnosing and managing sub-fertile stallions. There are many causes of sub-fertility in stallions and the key to successful management is correct diagnosis of the underlying cause. The cause can simply be an affect of aging or a primary pathologic condition. Once the cause is identified, proper strategies for collection, semen processing and insemination timing can be developed. Our large herd of recipient mares enables us to conduct fertility trials in order to determine the best protocol for optimum results. Some strategies include:

Cushioned Centrifugation: Semen is collected, extended and centrifuged over a liquid cushion. This process removes most of the stallions seminal plasma leaving a concentrated sperm pellet. The cushion is removed and the remaining sperm re-extended and divided into insemination doses.

Seminal Plasma Replacement: A small percentage of stallions’ seminal plasma is toxic to their own sperm cells. To correct this, the stallion is collected and cushioned centrifugation is utilized, removing all of the stallion’s seminal plasma. Because seminal plasma is necessary for fertilization, the removed plasma is replaced with seminal plasma collected from a stallion of known fertility, filtered to remove all of the sperm.

EquiPure Centrifugation: This procedure was recently developed by Dr. Dickson Varner of Texas A&M University. The procedure has been used to successfully extend the breeding career of several well known Quarter Horse stallions. Dr. Bliss has trained under Dr. Varner and has been successfully performing the procedure on several stallions for two years.  The process, first, involves cushioned centrifugation followed by centrifugation over the EquiPure product. EquiPure is made of coated silicone particles and it acts as a liquid filter, trapping the undesirable sperm and allowing the sperm containing normal DNA and morphology to pass through. The undesirable sperm and EquiPure are aspirated away, leaving only the desired sperm. This sperm is re-extended and insemination doses are prepared

Fractionated Semen Collection: This collection technique is used for stallions with urine or blood contamination in their semen. An open ended A.V. is used to separate out the different portions of the ejaculate, catching only the sperm rich fraction.

Chemical Ejaculation: This technique is utilized for select stallions with orthopedic or neurologic problems, preventing them from mounting a breeding phantom. It involves a drug regimen causing the stallion to spontaneously ejaculate while standing.