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Pre-breeding care of stallions (breeding and teaser):  Determine the status of the stallion for selected infections prior to use.  All stallions should be tested annually for EIA.  Some states (e.g., Kentucky and New York) require breeding stallions to be vaccinated yearly against EVA.  Maintaining permanent medical records confirming that seroconversion occurred as a result of vaccination could be important. 

Evaluating stallions prior to each breeding season for venereally transmitted diseases is a highly recommended practice since most major causes of venereal disease give rise to an asymptomatic carrier state in the stallion.  Detection of the persistently infected stallion requires laboratory examination of semen or other specimens from the reproductive tract.  Venereal organisms can easily be transmitted unknowingly within and from breeding centers using natural service or AI.   Regulatory officials must be notified if a stallion is identified as carrying CEMO, and treatment/control measures must be supervised by state/federal animal health officials.  For confirmed EAV shedding stallions, follow current recommendations (see Recommendations for Transported Semen as it is related to Equine Viral Arteritis (EVA) in the AAEP Resource Guide and Membership Directory; and Vaccination Schedule for Mares in the EVA discussion of this document) for breeding a mare to a known carrier/shedder stallion. 

Use hygienic procedures during breeding.  The breeding facility should be clean and well maintained.  Wrap the mare's tail with clean disposable or washable material to prevent contamination from the tail hairs at breeding.  The stallion’s penis, including the urethral diverticulum, should be rinsed only with clean water and then patted dry with a clean, dry disposable towel.  The person washing the genitalia should wear disposable gloves and change these between horses.  The routine use of soap or disinfectants should be discouraged as it may increase the risk of removal of the normal flora and repopulation of the penile integument with potential pathogens. 

To minimize the risk of cross-contamination between stallions, the external genitalia should be cleaned using a dedicated water bucket if possible.  Alternatively, the bucket should be cleaned and disinfected between stallions.  It is recommended that a disposable plastic liner be used in the bucket and changed between stallions.  Ensure that the water source is not contaminated with potentially pathogenic bacteria, such as Klebsiella and/or Pseudomonas.  Use an appropriate cleansing technique to minimize contamination of the clean water source by incorporating a standard ‘clean hand, contaminated hand’ technique.

Pre-breeding care of the mare:  Mares being bred by either natural service or AI should be examined to ensure that they are in the correct stage of the estrous cycle and are free of any clinical evidence of infection with potentially pathogenic microorganisms.  For imported mares, a series of diagnostic tests must be performed in a prescribed manner.  All regulatory requirements must be followed.  To verify requirements in your area, please check with your state/provincial animal health office.  

The facility for breeding mares should be safe for horses and facility personnel, and must be able to be cleaned and disinfected appropriately.  Prior to either live cover or AI, the tail of the mare should be wrapped with a clean disposable or washable material to prevent contamination from the tail hairs.  Thorough cleansing of the perineum prior to breeding reduces the likelihood of infection of the mare’s reproductive tract.  The person washing the mare’s external genitalia should wear disposable gloves and change gloves between mares.  The wash procedure may be accomplished with the gloved hand alone or with use of roll cotton, disposable paper towels or similar supplies.  A ready supply of clean water should be available, either via a water hose or a water bucket with a disposable liner.  Fresh cotton or paper towel should be used for each mare to minimize chances of contamination; if possible, and depending on circumstances, a separate bucket, or bucket with disposable plastic liner, will further minimize chances of cross contamination.  In addition, appropriate washing procedures should be used to minimize contamination of the clean water source by incorporating a standard ‘clean hand, contaminated hand’ technique.  A non-residual liquid soap or a povidone-iodine scrub may be used. 

A liberal amount of clean water is applied to the perineal area to remove gross debris.  A small amount of soap or scrub is applied to either the gloved hand, cotton/paper towels or directly onto the perineal area.  The perineal area is gently, but thoroughly scrubbed.  Cleaning should begin in the central region around the vulvar lips and then moved to the anus and beneath the tail head, followed by the regions lateral to (up to 6 inches) the vulva.  After the entire area has been scrubbed, the region should be rinsed with clean water.  The procedure should be repeated as needed until the area is clean.  The entire washed area should be dried with clean disposable paper towels after the final rinse.  It is important to gently part the vulvar lips and pass a moist paper towel or cotton pledget between the vulvar lips to insure that any particulate material, soap or water are removed from the vestibule.  It is also advisable to remove any accumulations of smegma from the clitoral fossa and clitoral sinuses, and to also clean the clitoral fossa when washing the vulvar area.