Routine pre-breeding tests

The Horserace Betting Levy Board (HBLB) publishes ‘codes of practice’ for pre-breeding tests annually. The risk of infectious diseases, including venereal and exotic diseases, has never been higher for the UK horse population, making it extremely important to perform routine pre-breeding tests.

Different studs / AI centres / veterinary clinics will specify which tests they require before breeding, so it is important to contact them well in advance of breeding to discuss the tests they will require and when they need to be carried out.

Requirements for mares coming into Bell Equine Veterinary Clinic for AI are:

  • A clitoral swab for CEM, Klebsiella pneumoniae and Psedomonas aeroginosa
  • Blood sample for EVA
  • Up to date influenza and tetanus vaccinations are recommended.

Any of the following possible requirements could be requested if using studs or other AI facilities:


  • Equine influenza and tetanus. All horses should be up to date with influenza and tetanus vaccinations. You may be asked to produce an up to date copy of your vaccinations with your passport.
  • Clitoral swabs are taken for CEM, Klebsiella pneumoniae and Pseudomonas aeroginosa after January 1st of the current year. This is carried out by the vet and can be performed at any stage of the reproductive cycle. Swabs sent for culture will required a week for the results to return, however, PCR testing is now available with results returned within 48 hours (although this is more expensive than culture). A CEM certificate will be produced and should accompany the mare to the stud / AI centre.
  • Endometrial swab for bacterial infection. This is taken by passing a guarded swab through the mare’s cervix into the uterus. This must be performed when the mare is in oestus and the cervix is relaxed and open. The swab usually takes 24-48hrs to process. A second swab is also used to collect cytology from the mare’s uterus. The slide is examined for the presence of increased numbers of neutrophils which is indicative of inflammation of the endometrium known as endometritis. These swabs can be performed in the preceding oestrus cycle before breeding or at the beginning of oestrus so that the mare can be covered in the same oestrus if the results are satisfactory. Most studs prefer to perform the swab on their own premises once the mare has arrived, but an increasing number of studs are requesting this before admission of the mare. It is therefore very important to check with the stud / AI centre or veterinary clinic first.
  • Blood sample for Equine Viral Arteritis Virus (EVA) after January 1st of the current year with a negative result. This test takes 24-48 hrs to process once it has reached the lab. This result should also accompany the mare to the stud.
  • Blood test for Equine Infectious Anaemia (EIA) – a “Coggins Test”. EIA is a notifiable disease and had not been seen in the UK since 1976. However, two confirmed cases in the UK early in 2010, has resulted in extra vigilance for this virus. Some studs may request this test to be performed before accepting a mare for breeding.
  • A recent addition to testing is a negative blood test result for “Strangles” (Strep equi). This needs to be taken within 28 days of the mare going to stud / AI centres. If the blood test returns borderline / positive, please contact BELL EQUINE for further advice.


  • Equine influenza virus and tetanus. All horses should be up to date with influenza and tetanus vaccinations. You may be asked to produce an up to date copy of your vaccinations with your passport.
  • A certificate for Contagious Equine Metritis (CEM) testing in the current breeding season according to HBLB protocols is required. Two sets of swabs taken at least 7 days apart; swabs are taken from the urethra, urethral fossa, penile sheath and pre-ejaculatory fluid where possible.
  • A negative blood tests for EVA and EIA.
  • Swab or blood sample for Strep Equi (strangles).
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