cem _29452_Layout 1 27/11/2014 16:54 Page 1

2015
Codes of
Practiceextract for contagious
equine metritis (cem)cem _29452_Layout 1 27/11/2014 16:54 Page 2

These Codes of Practice are published by:
Horserace Betting Levy Board
5th Floor
21 Bloomsbury Street
London WC1B 3HF
Tel: 020 7333 0043
Fax: 020 7333 0041
e-mail: equine.grants@hblb.org.uk
The full Codes of Practice and details of Approved Laboratories are available
online at http://codes.hblb.org.uk/.
These Codes do not imply any liability by the Horserace Betting Levy Board, theVeterinary Advisory Committee nor its Sub-Committees in the implementationof, nor responsibility for enforcement of, the Codes.

Acknowledgements
With thanks to the HBLB Codes of Practice Sub Committee for updating the text.
Photographs used in the Codes of Practice are by kind permission of Professor
Sidney Ricketts, Animal Health Trust, The National Stud, Equine Veterinary
Education and Istituto G.Caporale – Teramo, Italy.

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Introduction
This is an extract from the Codes of Practice 2013 booklet; it sets out voluntary
recommendations to help breeders, in conjunction with their veterinary surgeons,to prevent and control contagious equine metritis (CEM).
It is vital that owners/managers of breeding stock maintain vigilance and follow
the Codes, in conjunction with the attending veterinary surgeon, at all times. This
extract of the Codes of Practice set out minimum recommendations for disease
prevention and control. Breeders should implement additional precautions
whenever appropriate to their circumstances. Mare owners are strongly advised
to check whether the stallion stud and/or boarding stud to which their mare is tobe sent, or any local breeders’ association for that area such as the Newmarket
Stud Farmers Association (NSFA), has any requirements additional to thoseincluded in these Codes.
The recommendations within this extract of the Codes of Practice are common
to France, Germany, Ireland, Italy and the United Kingdom. CEM can havedevastating consequences; it compromises horse and pony welfare, disrupts
breeding activity, causes economic loss to mare and stallion owners and is costly
to deal with.
The disease is highly contagious and uncontrolled infection in just one horse or
pony can transmit easily to others, potentially escalating to local and national
outbreaks.
CEM is notifiable by law and, ultimately, outbreaks on any scale can lead to
Britain losing its horse export status. To avoid these consequences, breeders
should aim to prevent disease, and control its spread if a case is suspected oroccurs, by implementing the recommendations in this Codes of Practice extract.
If a case occurs, it is important to inform owners of other horses that are at risk ofinfection through contact with the affected horse/premises so that they can treat
their horse and implement measures to stop any further spread of disease to otherhorses.
Throughout this extract, the term:• ‘Horse’ includes mares and stallions of any breed of horse or pony.
• ‘Stallion’ includes stallions of any breed to be used for naturalmating, teasingor semen collection for AI.

• ‘Breeding activity’ includes natural mating, teasing and collection andinsemination of semen.

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CODE OF PRACTICEFOR CONTAGIOUS
EQUINE METRITIS,KLEBSIELLAPNEUMONIAE AND
PSEUDOMONAS
AERUGINOSA

5

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CODE OF PRACTICE FOR CEM,KLEBSIELLA PNEUMONIAE AND
PSEUDOMONAS AERUGINOSAThis Code of Practice covers disease caused by three species of bacteria:• Taylorella equigenitalis (the contagious equine metritis organism - CEMO)
Contagious equine metritis (CEM), caused by this organism, occurs widely inthe non-Thoroughbred population, and to a limited extent in Thoroughbreds,
in mainland Europe.

• Klebsiella pneumoniae (K. pneumoniae)
There are many capsule types of K. pneumoniae, most of which do not cause
venereal disease. However, types 1, 2 and 5 may be sexually transmitted.
Therefore, when K. pneumoniae is identified from breeding stock, tests todetermine the capsule type(s) present must be undertaken.

• Pseudomonas aeruginosa (P. aeruginosa)
Not all strains of P. aeruginosa cause venereal disease but there is no reliable
method to differentiate between the strains. Therefore, all isolates should beconsidered as potential venereal pathogens.
Both K. pneumoniae and P. aeruginosa occur sporadically within Europe.

Notification Procedures
Contagious equine metritis
In the UK, isolation of the CEMO is notifiable by law. This is a statutory requirement
under the Infectious Diseases of Horses Order 1987 and any positive samples must
be reported by the testing laboratory to the Department for Environment, Foodand Rural Affairs (Defra) via the local Field Service office of the Animal & Plant
Health Agency (APHA). A list of APHA regional contact telephone numbers
appears in Appendix 1 and also on Defra’s website at https://www.gov.uk/
government/organisations/animal-and-plant-health agency/about/access-andopening#field-services. In confirmed cases, Defra asks, initially, that the breeders
and veterinary surgeons involved comply with this Code of Practice as a meansof controlling the spread of the disease.
If an assessment by Defra concludes that voluntary compliance is not sufficient tocontrol the disease, they may serve Statutory Notices on the affected premises,
declaring them an infected place and imposing mandatory requirements,
including:• taking samples or obtaining information to establish the source and extent ofdisease;7

cem _29452_Layout 1 27/11/2014 16:54 Page 8• prohibiting or controlling movement of any horse, carcase or other item;• prohibiting the breeding activities of any implicated horses;• disinfection or destruction of infected articles or materials;• cleansing and disinfection of premises and vehicles.
In the event of statutory powers being invoked, Defra would nominate thelaboratories to undertake the testing of all samples required by the subsequent
investigation.
Failure to comply with Statutory Notices is an offence under the Animal HealthAct 1981 and may lead to prosecution.
It is advisable for owners, or a person authorised to act on their behalf, to informthe national breeders’ association if CEMO is isolated.

Klebsiella pneumoniae and Pseudomonas aeruginosaIn the UK, isolation of K. pneumoniae or P. aeruginosa is not notifiable by law.
However, if infection occurs in stallions, it is advisable for the owner, or a person
authorised to act on their behalf, to inform the national breeders’ association.

Clinical Signs
Mares
The severity of disease in mares varies. There are two states of infection:• the active state in which the main outward sign is a vulval discharge which
may range from very mild to extremely profuse;• the carrier state in which there are no outward signs of infection. However,
the mare remains capable of transmitting infection because thebacteria are established on the surface of the clitoris, the clitoral fossa andsinuses and, in the case of K. pneumoniae and P. aeruginosa, sometimes in
the urethra and bladder.

Stallions
Remember: ‘stallion’ means mating stallions, teasers and stallions used for AI• Infected stallions do not usually show clinical signs of infection but thebacteria are present on their penis, sheath and, in the case of K. pneumoniae
and P. aeruginosa, sometimes in the urethra and bladder. These stallions caninfect mares during mating, teasing or AI.

• Occasionally, the bacteria may invade the stallion’s sex glands, causing pus
and bacteria to contaminate the semen.

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Transmission of Disease
Infection can be transmitted between horses in any of the following ways:• direct transmission during natural mating;• direct transmission during teasing. An infected teaser can transmit disease
to mares through contact with his genitalia;• indirect transmission during teasing. A teaser can transmit infected vulval
discharge between mares through genital or naso-genital contact;• transmission to mares if semen used for AI comes from infected stallions or
has been contaminated with the bacteria during semen collection orprocessing;• indirect transmission via the hands and equipment of staff or veterinary
surgeons who have handled the tail or genitalia of an infected horse.

Prevention
The most important means of preventing infection are:• establishing freedom from infection before commencing breeding
activities;• checking that horses remain free from infection during breeding activities;• exercising strict hygienic measures during breeding activities.
No vaccines against these bacterial diseases are available.
Freedom from infection
Establishing freedom from infection before, and checking that horses remain freefrom infection during, breeding activities involves a veterinary surgeon taking
samples (‘swabs’) from the genitalia of mares and stallions for testing (‘culturing’)
in a laboratory. The laboratory will test for the presence of the CEMO, K.
pneumoniae and P. aeruginosa. If the results are negative, the horse is free from
infection and breeding activities may take place. If the results are positive, thehorse is infected and must be treated, re-tested and cleared. The horse must not
be used for breeding activities at this time. If a swab is positive for the CEMO, theNotification Procedures on page 7 also apply, and an investigation of the sourceand extent of the disease will be undertaken.

Note
Also see the
AI Guidelines
on page 75

No horse should be used for breeding activities until or unless all swab results areavailable and negative.

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Different types of swab and culture are recommended for different
circumstances in this Code of Practice. For further information on the types ofswab, taking and submission of swabs, culture and return of results, see ‘Diagnosis’
on page 14.
Recommendations for establishing freedom from infection in mares and stallions
before breeding activities commence, and for checking that horses remain freefrom infection during breeding activities, are on pages 10–17.
Hygiene measures
Staff should be made aware of the risk of direct and indirect transmission of infection.
They should always wear disposable gloves when handling the tail or genitalia andchange gloves between each horse. Separate sterile and, where appropriate,
disposable equipment and clean water should always be used for each horse.
Biosecurity protocols specific to AI are described in further detail in the Guidelines on AI.
Prevention recommendations
These are minimum recommendations. Mare owners should check whether thestallion stud, boarding stud or local breeders’ association (eg NSFA) has any
additional requirements.

Mares
After 1st January in any year, and before a mare is mated/teased/
inseminated, the following should be undertaken:
References to swab
testingmeans
appropriate testing by
culture and/or PCR,
where a laboratory isapproved by HBLB
for this method••

ascertain whether the mare is ‘high risk’ or ‘low risk’ (see Appendix 2);
complete a Mare Certificate (see Appendix 3) and send it to the stallion
owner/manager;•arrange for a veterinary surgeon to take the appropriate swabs (seeprotocol below and on page 11) and send them to a laboratory for testing;•

distribute the resulting Laboratory Certificates (see Appendix 4) inaccordance with the protocol on page 11.

If the results are negative, the mare is free from infection and breeding
activities may commence. If they are positive, she is infected and must not bemated, teased or inseminated until she has been treated and cleared under
the direction of the attending veterinary surgeon, and, in the case of the
CEMO, in accordance with any Defra requirements.
Swabbing protocol for mares temporarily or permanently resident at stallion
stud (pre-breeding)Mare status

Type of swab

When/where taken

Low risk

ClitoralHome premises or stallion stud Aerobic and microaerophilic

Endometrial

During oestrus at stallion stud

Clitoral

Before arrival at stallion studAerobic and microaerophilic

ClitoralOn arrival at stallion studAerobic and microaerophilic

Endometrial

During oestrus at stallion studAerobic and microaerophilicHigh risk

10

Culture/PCR

Aerobic

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Swabbing protocol for walking-in mares (pre-breeding) or for mares being
presented for AI (considered as ‘low risk’)
The following applies to mares which will not be resident on the same premises
as the stallion, but will be ‘walked in’, either from their home premises or from aboarding stud. If ‘high risk’ walking-in mares are going to a boarding stud, thatstud should either be under the control of, or meet full approval of, the stallion
owner/manager. The veterinary surgeons involved should liaise closely to ensure
adherence to the Code of Practice and to arrange any additional precautions
that may be required.
Mare status

Type of swab

When/where taken

Culture/PCR

Low risk

ClitoralHome premises or boarding studAerobic and microaerophilic

Endometrial

During oestrus at home premises

Aerobic

References to swab
testingmeans
appropriate testing by
culture and/or PCR,
where a laboratory isapproved by HBLB
for this method

or boarding studHigh risk

2 x clitoral

At least seven days apart at

Aerobic and microaerophilic

home premises or boarding stud
Endometrial

During oestrus at home premises

Aerobic and microaerophilic

or boarding stud

Protocol for distribution of Laboratory CertificatesLaboratory Certificates relating to pre-breeding swabs taken from mares at thehome premises should be sent in advance to the stallion owner/manager and,
where appropriate, to the boarding stud. Certificates relating to pre-breedingswabs taken from mares at boarding studs should be sent in advance to thestallion owner/manager.
Before a mare is mated, the mare owner/manager is advised to request aLaboratory Certificate confirming the stallion’s disease free status in the current
breeding season.
Mare owners/managers should not accept semen for AI without obtaining
evidence that the donor stallion was free from infection when the semen wascollected. In the UK, this evidence would be provided by a Laboratory Certificate
confirming the stallion’s disease free status in the current breeding season. When
importing semen, it should be accompanied by documentary evidence of
freedom from infection with all three bacteria and the original import certificate.
If the mare does not conceive on first (or subsequent) matings, and her return tooestrus is normal, she should be swabbed again before being re-mated to checkthat she is not infected as a result of the previous mating, according to theprotocol on page 12.
The mare may be re-mated on the basis of negative swab results. If the results are
positive, she is infected and must not be mated, teased or inseminated until she
has been treated and cleared under the direction of the attending veterinary
surgeon, and, in the case of the CEMO, in accordance with any Defra
requirements.

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Swabbing protocol for mares temporarily or permanently resident at stallion
stud (repeat matings)
Mare status

Type of swab

When/where taken

Culture/PCR

Low risk

Endometrial

During oestrus at stallion studAerobic

High risk

Endometrial

During oestrus at stallion studAerobic andmicroaerophilic

Swabbing protocol for walking-in mares (repeat matings)

References to swab
testingmeans
appropriate testing by
culture and/or PCR,
where a laboratory isapproved by HBLB
for this method

The following swab recommendations apply to mares which will not be
resident on the same premises as the stallion, but will be ‘walked in’, either fromtheir home premises or from a boarding stud. If ‘high risk’ walking-in mares aregoing to a boarding stud, it should either be under the control of, or meet full
approval of, the stallion owner/manager. The veterinary surgeons involved
should liaise closely to ensure adherence to the Code of Practice and toarrange any additional precautions that may be required.
Mare status

Type of swab

Low risk

Endometrial

When/where taken

Culture/PCR

During oestrus at home premises Aerobic
or boarding studHigh risk

Endometrial

During oestrus at home premises Aerobic andor boarding stud

microaerophilic

Protocol for distribution of Laboratory CertificatesLaboratory Certificates relating to repeat swabs taken from mares at the homepremises should be sent in advance to the stallion owner/manager and,
where appropriate, to the boarding stud. Certificates relating to repeat swabs
taken from mares at boarding studs should be sent in advance to the stallion
owner/manager.

If any mare returns to oestrus at an unusual (especially shorter than normal)
time, this may be because she is infected. Repeat clitoral and endometrial
swabs should be taken and cultured under aerobic and microaerophilic
conditions.
If any mare changes premises, or stallions, between matings, repeat clitoraland endometrial swabs should be taken at least seven days after mating by theoriginal stallion and cultured under aerobic and microaerophilic conditions.
These are minimum recommendations. Mare owners should check whether
the stallion stud, boarding stud or local breeders’ association (eg NSFA) has
any additional requirements.

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Stallions

After 1st January in any year and before a stallion is used formating/teasing/semen collection, the owner/manager should:••

ascertain whether the stallion is ‘high risk’ or ‘low risk’ (see Appendix 2);
arrange for swabs to be taken by a veterinary surgeon in accordancewith the protocol below;•

ensure that a Laboratory Certificate (see Appendix 4) confirming themare’s disease free status in the current breeding season, and a current
Mare Certificate (see Appendix 3) are received for each mare to bemated, teased or inseminated at the stallion’s premises;•

ensure that a Laboratory Certificate confirming the stallion’s disease
free status in the current breeding season is made available to mareowners/managers.

Protocol for swabbing (pre-breeding)After 1st January and before any breeding activity is commenced, two sets ofswabs (see definition on page 14) should be taken from all stallions at aninterval of no less than seven days and cultured aerobically andmicroaerophilically.

References to swab
testingmeans
appropriate testing by
culture and/or PCR,
where a laboratory isapproved by HBLB
for this method

If the results of swab testing are negative, the stallion is free from infection andbreeding activities may commence. If they are positive, he is infected and mustnot be used for mating, teasing or semen collection until he has been treatedand cleared under the direction of the attending veterinary surgeon and, in thecase of the CEMO, in accordance with any Defra requirements.
The following should be carried out during the breeding season to check thatthe stallion has not become infected:‘High risk’ stallions and any other stallion standing on a stud for the first time
warrant additional precautions. The first four mares mated with them should bescreened for the CEMO, K. pneumoniae (capsule types 1, 2 and 5) and P.
aeruginosa by taking a clitoral swab two days after mating. If the maresubsequently returns to oestrus, an endometrial swab should be taken at thattime. These swabs should always be tested aerobically and microaerophilically.
In stallions, bacterial growth of the CEMO is generally more easily recoverable
after mating. Swabbing of all stallions after their first few matings in any season
should therefore be considered in conjunction with the attending veterinary
surgeon. In addition, mid-season swabbing should be considered for all stallions
and teasers. These swabs should always be tested by aerobic and microphilic
culture and/or by PCR testing.
Remember: ‘stallion’ means mating stallions, teasers and stallions used for AI

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Diagnosis
Laboratory diagnosis is essential to confirm the presence or absence of the CEMO,
K. pneumoniae and P. aeruginosa in swabs taken from mares and stallions.
Types of swab
Mares
There are two types of swab:

References to swab
testingmeans
appropriate testing by
culture and/or PCR,
where a laboratory isapproved by HBLB
for this method

Clitoral swab: taken from two sites; the clitoral fossa and the clitoral sinuses, at
any point during the reproduction cycle to demonstrate whether these sites arefree from infection. In the case of pregnant mares who have had difficult
foalings requiring veterinary attention and antibiotic treatments, additional
clitoral swabs should be taken after foaling and more than 7 days after
antibiotic treatment has finished, in addition to routine endometrial swabs, inorder to rule out acquired Pseudomonas aeruginosa and Klebsiellapneumoniae infections. Providing the pre-foaling clitoral swab was certified
negative for Taylorella equigenitalis, the additional post-foaling clitoral swab
may be tested by aerobic culture only, or by PCR.
Endometrial swab: taken during oestrus from the lining of the uterus via theopen cervix to demonstrate whether the uterus is free from infection.
Mare swabs taken for disease prevention purposes should be tested
according to the recommendations on pages 10–12.
Note: These are minimum recommendations. Mare owners should check
whether the stallion stud, boarding stud or local breeders’ association (egNSFA) has any additional requirements.

StallionsSwabs should be taken from three sites; the urethra, urethral fossa and penile
sheath, plus pre-ejaculatory fluid when possible. Separate swabs should be
used for each site and tested by aerobic and microaerophilic culture and/or
by PCR, in all circumstances.

Further information on how to collect equine genital swabs in stud practice for theprevention of venereal diseases, as recommended by the Codes of Practice, isavailable online at http://codes.hblb.org.uk/index.php/page/40
Taking swabs
All swabs should be taken by a veterinary surgeon, who should:• submerge the swabs in Amies Charcoal Transport Medium (which must bewithin the expiry date) to protect them from the damaging effects of light,
which will readily kill any CEMO, K. pneumoniae or P. aeruginosa present;• label them clearly to show the date and time they were taken, the horse’s
name and the site of swabbing;14

cem _29452_Layout 1 27/11/2014 16:54 Page 15• indicate clearly whether aerobic, microaerophilic or both cultures, and/or
PCR are required;• submit them to an Approved Laboratory for testing.
A list of laboratories in Britain approved by the Horserace Betting Levy Board forthe purposes of testing for the CEMO, K. pneumoniae and P. aeruginosa isavailable from http://codes.hblb.org.uk/index.php/page/index/139.
Submitting swabs to Approved Laboratories
The Approved Laboratories must set up swabs for conventional microaerophilic
culture for CEMO within 48 hours of them being taken from the horse as thisorganism is short lived, even in bacteriological transport medium. Veterinary
surgeons submitting swabs by routine postal services are, therefore, advised not
to take swabs on Fridays, Saturdays or Sundays as they may not arrive in time. If
weekend or bank holiday swabbing is unavoidable, the veterinary surgeon
should ensure that the laboratory is open and able to commence cultures within
the 48 hours. In this event, a suitable courier service should be used to deliver theswabs. If a swab does not arrive in time, the laboratory should reject it and advise
the veterinary surgeon to repeat the swabbing.

References to swab
testingmeans
appropriate testing by
culture and/or PCR,
where a laboratory isapproved by HBLB
for this method

However, time constraints do not apply to swabs submitted to laboratories thatare approved to run PCR tests for CEMO as specific DNA from non-viableorganisms can be detected for long periods. Experience suggests that swabs
cultured aerobically for K. pneumoniae and P. aeruginosa are not so time
sensitive and these organisms have a long life in bacteriological transport
medium, as they do in the environment.
Laboratory culture of swabs
Laboratories can culture swabs in two ways: aerobically and microaerophilically(see Glossary, Appendix 10). The results of culture will be returned by thelaboratory on an official Laboratory Certificate. When planning the timing ofbreeding activities, breeders and veterinary surgeons should be aware that theresults of microaerophilic culture results will not be available for at least sevendays and aerobic culture results will not be available for 48 hours (to exclude thepossibility of slow-growing P. aeruginosa organisms).
Other laboratory tests
Polymerase chain reaction (PCR) testing of swabs for the CEMO, Klebsiellapneumoniae and Pseudomonas aeruginosa is now validated for industry
screening purposes. PCR testing is not recognised for import/export testing in the
UK. Breeders and veterinary surgeons may find PCR test results helpful, as they
may be available within 24 hours of arrival at a laboratory that is able toundertake PCR testing. Positive PCR results will need to be further investigated byconventional culture to help determine their significance and, in the case of
Klebsiella pneumoniae, for capsule typing. Positive PCR results for CEMO must bereported to Defra. The immunofluorescence test (IFT) for CEMO may be used inaddition to culture, although this test is only available in France at present.

Note
The term ‘at risk’
relates to any horsewhich may havebecome infected asa result of direct orindirect transmissionof the disease.

15

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Control of Infection
If infection with any of the three organisms is suspected in any mare, stallion orteaser on the basis of clinical signs, all breeding activities must cease
immediately. The affected horse(s) should be isolated and swabbed by theattending veterinary surgeon.
If the CEMO, K. pneumoniae (capsule types 1, 2 or 5) or P. aeruginosa is
subsequently isolated from any mare, stallion or teaser:
1.

Stop mating, teasing and collection and insemination of semen
immediately;2.

Seek veterinary advice immediately;

3.

Isolate and treat the infected horse(s) as advised by the attending
veterinary surgeon. In the case of the CEMO, the laboratory will havenotified Defra, who may give directions which must be followed;

4.

Arrange swabbing of any at risk horses, as advised by the attending
veterinary surgeon or by Defra;

5.

Disinfect all equipment used for breeding procedures.

6.

Inform all owners of mares booked to the stallion, including any whichhave already left the premises;

7.

Inform people to whom semen from the stallion has been sent;

8.

Inform the national breeders’ association;

9.

Arrange for one straw from every ejaculate of stored semen from
infected and at risk stallions to be tested by a laboratory. If a straw fromany ejaculate is infected, all straws from that ejaculate should bedestroyed;

10.

Any at risk pregnant mare must be foaled in isolation. The placenta must
be incinerated. Foals born to these mares should be swabbed threetimes, at intervals of not less than seven days, before three months ofage. These swabs should all be tested by aerobic and microaerophilic
culture and/or by PCR;

• Filly foals: swab the clitoral fossa.
• Colt foals: swab inside the penile sheath and around the tip of thepenis.
11.

Do not resume any breeding activity until freedom from disease has
been confirmed in all infected horses (see below). The approval of theattending veterinary surgeon or, in the case of CEMO, of the APHA,
should be obtained before resumption of breeding activity.

Remember: in any suspected or confirmed disease situation, the implementationof strict hygienic measures is essential.
In the case of the CEMO, if Defra do not believe voluntary compliance is sufficient
to control infection, they will impose statutory requirements.

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Treatment
Any necessary treatment will be determined by the attending veterinary surgeon.

Confirmation of Freedom from Disease
Following infection with any of the three bacteria, breeding activities should only
be resumed with approval from the attending veterinary surgeon, and in the caseof the CEMO, the APHA, who must be satisfied that infected and in-contact
horses have been investigated, treated as appropriate and subsequently clearedon the basis of negative swabs.
The first post treatment swabs should be taken seven or more days after thetreatment has ended. All post treatment swabs should be tested by aerobic andmicroaerophilic culture and/or by PCR. All positive isolates of K. pneumoniae
should be capsule typed where they are identified on post-treatment samples,irrespective of whether pathogenic K. pneumoniae was isolated prior totreatment. All Klebsiella pneumoniae PCR results will need culture tests also
performed to provide bacteria for capsule typing.
Mares
Three clitoral swabs should be taken at intervals of at least seven days andthree endometrial swabs should be taken during the next three oestrous
periods. All results must be confirmed as negative before any breeding
activities resume. If any result is positive, further investigation should beundertaken in conjunction with the attending veterinary surgeon.

StallionsThree sets of penile swabs should be taken at intervals of at least seven days
and negative results confirmed. Thereafter, the first three mares mated orinseminated by the stallion should have clitoral swabs taken three times atintervals of at least seven days, starting two days after mating or
insemination. If any of these swab results are positive, breeding activities
should cease pending further investigation in conjunction with the attending
veterinary surgeon.

Export Certification
Swabs taken for examination for the CEMO from horses in the United Kingdom forthe purpose of official export health certification must be sent to the designatedlaboratory within the APHA. This is the APHA Regional Laboratory, Bury St
Edmunds. In the case of horses that are to be exported from Northern Ireland,swabs should be sent to the Veterinary Science Division Laboratory, Belfast.

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APPENDIX 1
Contact information for reporting notifiabledisease suspects to Animal & Plant HealthAgency (APHA) Field Offices in England,
Scotland and Wales
There are statutory requirements that suspicion of the notifiable diseases of CEM,
EVA, EIA and dourine must be reported immediately to the appropriate Field
Service office of the Animal & Plant Health Agency (APHA). The RVLs are basedat the Field Offices, as listed below.
When you telephone your local Field office, tell the switchboard that you aretelephoning to report a suspect case of notifiable disease, and ask to speak to
the Duty Vet. The Duty Vet is trained to handle reports of notifiable disease andwill discuss the case with you. Many reports can be ruled out based on
information gathered during this initial telephone conversation.
However, if a notifiable disease cannot be ruled out, the Duty Vet will arrange fora Veterinary Officer to visit the premises, usually within two hours. If considered tobe appropriate, restrictions preventing movements on or off the premises, may beserved verbally over the phone at this time.
When the Veterinary Officer visits, they will examine the affected animal, together
with the other animals on the premises. Disease is often ruled out at this point andrestrictions are lifted immediately. If disease cannot be ruled out by thisexamination and inquiry, then samples may be taken and sent to a laboratory fortesting. In this case, restrictions will remain in place until negative laboratory results
are obtained – this is often in less than 24 hours. If negative results are obtained
then restrictions are lifted immediately.

England: Midlands Region
Telephone: 01162 787451
Email: AHROMidlands@ahvla.gsi.gov.uk
The Midlands region includes Birmingham District, City of Derby, City of Leicester,City of Nottingham, City of Stoke-on-Trent, Coventry District, Derbyshire, DudleyDistrict, Herefordshire, Leicestershire, Lincolnshire, Northamptonshire,
Nottinghamshire, Rutland, Trent, Sandwell District, Shropshire, Solihull District,Staffordshire, Telford & Wrekin, Walsall District, Warwickshire, Wolverhampton
District, Worcestershire.

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North East Region
Telephone: 0300 303 8269
Email: EnglandNorth@ahvla.gsi.gov.uk

North West Region
Telephone: 0300 303 1324
Email: EnglandNorth@ahvla.gsi.gov.uk

South East Region
Telephone: 01284 778150
Email: AHROSouthEast@ahvla.gsi.gov.uk
The South East region covers Bedford, Bracknell Forest, Brighton & Hove,
Buckinghamshire, Cambridgeshire, Central Bedfordshire, East Sussex, Essex,
Greater London, Hampshire, Hertfordshire, Isle of Wight, Kent, Luton, Medway,
Milton Keynes, Norfolk, Oxfordshire, Peterborough, Portsmouth, Reading, Slough,Southampton, Southend-on-Sea, Suffolk, Surrey, Thurrock, West Berkshire, West
Sussex, Windsor & Maidenhead, Wokingham.

South West Region
Telephone: 01392 266373
Email: APHASWEngland@apha.gsi.gov.uk
The South West region covers Bath & North East Somerset, Bournemouth andPoole, City of Bristol, City of Plymouth, Cornwall, Devon, Dorset, Gloucestershire,
Isles of Scilly, North Somerset, Somerset, South Gloucestershire, Swindon, Torbay,
Wiltshire.

Yorkshire & The Humber Region
Telephone: 0300 303 1324
Email: EnglandNorth@ahvla.gsi.gov.uk

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Wales:
Telephone: 0300 303 8268
Email: APHA.CymruWales@apha.gsi.gov.uk

Scotland: Ayr
Telephone: 01292 291350
Email: AHVLA.Scotland@ahvla.gsi.gov.uk

Scotland: Galashiels
Telephone: 01896 758806
Email: AHVLA.Scotland@ahvla.gsi.gov.uk

Scotland: Perth
Telephone: 01738 602211
Email: AHVLA.Scotland@ahvla.gsi.gov.uk

Scotland: Inverness
Telephone: 01463 728800
Email: AHVLA.Scotland@ahvla.gsi.gov.uk

Scotland: Inverurie
Telephone: 01467 626610
Email: AHVLA.Scotland@ahvla.gsi.gov.uk

For further contact information, see
https://www.gov.uk/government/organisations/animal-and-plant-health-agency/about/access-and-opening

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APPENDIX 2
Definition of ‘high risk’ and ‘low risk’ mares
and stallions‘High risk’ mares are:1.

Mares from which the CEMO, K. pneumoniae (capsule types 1, 2 or 5) or
P. aeruginosa has been isolated. The ‘high risk’ status will remain until
three sets of negative swabs have been taken at three different
oestrous periods in each of two years;

2.

Mares which have visited any premises on which the CEMO has
been isolated within the previous 12 months;

3.

Mares arriving from France, Germany, Ireland, Italy and the UK whichhave been mated during the last breeding season with stallions resident
outside these countries;

4.

All mares who have been in countries other than France, Germany,
Ireland, Italy and the UK within the last 12 months.

‘Low risk’ mares are any mares not defined as ‘high risk’.
‘High risk’ stallions are:1.

Stallions which have not previously been used for breeding purposes;

2.

Stallions from which the CEMO, K. pneumoniae (capsule types 1, 2 or 5)
or P. aeruginosa has been isolated. The ‘high risk’ status will remain until
treatment has been undertaken and required swab results (see page17, ‘Confirmation of freedom from disease’) are negative;

3.

Stallions which have, in the last 12 months, been at any premises on
which the CEMO, K. pneumoniae (capsule types 1, 2 or 5) or
P. aeruginosa has been isolated;

4.

Stallions which have mated a mare which has not been swabbed
negative in accordance with the Code of Practice.

‘Low risk’ stallions are any stallions not defined as ‘high risk’.

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APPENDIX 3

CONTAGIOUS EQUINE METRITIS AND OTHER
EQUINE BACTERIAL VENEREAL DISEASES

2 01 5 S E A S O N
MARE CERTIFICATEThis certificate must be completed by the mare owner/manager and be lodged with theprospective stallion owner/manager before the mare’s arrival.
Name of mare _______________________________________________________________
Passport number (where available) _______________________________________________Name and address of owner ______________________________________________________________________________________________________________________________
Address of premises where mare currently resides _____________________________________________________________________________________________________________In 2012 the above mare boarded* at __________________________________________studwhilst visiting ________________________ (stallion) result__________________________In 2013 the above mare boarded* at___________________________________________studwhilst visiting ________________________ (stallion) result__________________________In 2014 the above mare boarded* at __________________________________________studwhilst visiting ________________________ (stallion) result__________________________
Additional information including the results of positive bacteriological examinations for the CEMO,
Klebsiella pneumoniae and Pseudomonas aeruginosa at any time:____________________________________________________________________________________________________________________________________________________Name (please print)___________________________________________________________

Signature ___________________________________________Date ___________________*If no boarding stud was used, provide the name and address of the premises where the mareresided.

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APPENDIX 4

LABORATORY CERTIFICATE(CERTIFICAT LABORATOIRE)

2 01 5 S E A S O N
For use only by Approved Laboratories* (Laboratoires agréés)
Swabs contained in transport medium and labelled as collected from the stallion/teaser/marenamed (Nom du cheval)_________________________________________________________________________
Passport number (where available) (Numéro SIRE/carnet signalétique) _______________________

5
1
0
2

from the following sites (Prélèvements effectués) ______________________________________________________________________________________________________________
were submitted by (Nom du vétérinaire ayant effectué les prélèvements) ________________________________________________________________________________________________
for bacteriological examination on (date[s]) (Fait le) __________________________________I (Je) ______________________________________________________________________of (Laboratory) (Nom du laboratoire agréé) ___________________________________________
certify that the above swabs were examined: (je sousigné/e atteste que les prélèvements mis en culture),a) with the following results:b) by testing method:(ont livré les résultats suivants):(méthode utilisée):

POSITIVE

NEGATIVE

CULTURE

positifnégatif

PCR

Taylorella equigenitalis (CEMO)(Métrite contagieuse des Equidés)

Pseudomonas aeruginosa(Pseudomonas aeruginosa)

Klebsiella pneumonia(Klebsiella pneumoniae)

Where K. pneumoniae was isolated, capsule type(s) identified were ____________________(Type(s) capsulaire[s])Name and qualifications (Responsable du laboratoire agréé) (please print) ____________________________________________________________________________________________
Signature ___________________________________________ Date __________________
Laboratory name and address (Nom et adresse du laboratoire agréé) _________________________________________________________________________________________________*An Approved Laboratory is one whose name is published on the Horserace Betting Levy Board website http://codes.hblb.org.uk/index.php/page/139 for the year
December 2014 – November 2015
†In the event of a positive Klebsiella pneumoniae isolate, capsule typing should be performed and the results detailed to aid the determination of potential
venereal pathogenicity.

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APPENDIX 5
EAV – Identification of shedding stallions
When a seropositive stallion is identified, it is vital to establish whether he isshedding the equine arteritis virus (EAV) in his semen. If so, he is a primary sourceof infection. He must be kept in strict isolation for at least 28 days while the following
methods are used under the direction of the attending veterinary surgeon andthe local Field Service office of the APHA to determine whether he is a shedder:
Detecting virus in semen
The virus isolation (VI) test is the internationally recognised test for the detection of
EAV in semen and PCR (Polymerase Chain Reaction) testing may be used toprovide an initial indication of virus in semen.
A whole ejaculate of semen should be sent to a laboratory; a second wholeejaculate should be collected at least seven days later and sent to the samelaboratory. Transport requirements (eg cooling) should be arranged with thelaboratory. If EAV is detected in either sample, the stallion is a shedder. He must
be kept in isolation and not be used for any breeding activities while he is still
shedding, unless permitted under an official licence issued by Defra.
In the event of negative results for both semen samples, experience has shownthat it is advisable to confirm these results by test mating.
Test matingThis must be done in strict isolation and under veterinary supervision. The stallion
and mares must have no contact with other horses. The following procedure
should be followed:• Identify at least 2 seronegative mares;• Take and store blood samples from each and then isolate the mares.
Consult the testing laboratory about storage conditions;• Mate each mare twice a day with the stallion on 2 consecutive days;• Keep the mares in isolation;• After 28 days, take blood samples and send them, with the pre-isolation
samples, to the laboratory.
If the mares remain seronegative, the stallion is unlikely to be a shedder and canbe released after a clinical examination.
If one or more mares become seropositive, the stallion is a shedder. He must be
kept in isolation and not be used for breeding activities while he is shedding,unless permitted under an official licence issued by Defra.
Seropositive mares must remain in isolation until they have a stable or declining
antibody level in two sequential blood tests taken at an interval of at least 14
days.

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APPENDIX 6
Guidance on isolation
The Codes of Practice often refer to the isolation of horses. In its strictest sense,‘isolation’ means a separate facility with separate staff, separate protective
clothing, separate utensils/equipment and thorough steam cleaning anddisinfection of stables between each occupant. The following guidelines, at least,
should be adhered to:Premises
1.

The isolation facility should be a separate, enclosed building of sound,permanent construction, capable of being cleansed and disinfected
effectively.

2.

It must not be possible for other horses to approach within 100 metres of
the isolation facility while it is in use.

3.

An adequate supply of fresh, clean water must be available at all times
for the isolated horses and for cleaning purposes.

4.

Adequate supplies of food and bedding material for the whole of theisolation period must be made available and stored within the isolation
facility before isolation commences.

5.

Equipment and utensils used for feeding, grooming and cleansing must
be used only in the isolation facility.

6.

Protective clothing must be available at the entrance to the isolation
facility and not be taken outside of this facility.

7.

A separate muck heap should be used within the isolation facility.

Procedures

26

1.

Before use, all fixed and moveable equipment and utensils for feeding,grooming and cleansing within the isolation facility must be disinfectedusing an approved disinfectant. A list of these is provided on the Defra
website http://disinfectants.defra.gov.uk/Default.aspx?Module=Approvals
List_SI (select only ‘General’ for suitable products).

2.

Attendants of the isolated horses must have no contact with any otherhorses during the isolation period.

3.

The isolation period for all isolated horses shall be deemed to start fromthe time of entry of the last horse.

4.

No person may enter the isolation facility unless specifically authorised
to do so.

5.

When no attendants are on duty, the facility must be locked securely toprevent the entry of unauthorised persons.

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If such strict measures are not possible in practice, the owner/manager of thepremises where isolation is needed should devise their own isolation programme
and procedures in conjunction with the attending veterinary surgeon. Theseshould include, for example:•

The designation of a yard and associated paddock as an isolation area
in a geographically separate area of the premises.

•

The designation of individual staff to work in the isolation facility withseparate protective clothing and approved disinfectants as and whenrequired. These individuals should either not be involved with work on
the rest of the premises during periods of isolation, or they should complete
their work on the rest of the premises before entering the isolation area.
They should not return to other areas of the premises thereafter.

•

The establishment of ‘standard procedures’, the precise details of
which should be agreed with the attending veterinary surgeon as theymight vary according to individual circumstances.

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APPENDIX 7
Transport
There is significant potential for transmission of infectious disease during transport.
Cleanliness and hygiene on board all forms of transport is the responsibility of thevehicle owner in private transport and the vehicle operator in contracted transport.
The following notes are for guidance in either case.

28

1.

Vehicles should be cleaned and disinfected frequently and regularly, using
approved disinfectants capable of killing bacteria and viruses. A list ofthese is provided on the Defra website http://disinfectants.defra.gov.uk/
Default.aspx?Module=ApprovalsList_SI (select only ‘General’ for suitableproducts).

2.

Vehicles should be cleaned before horses are loaded.

3.

Prior vaccination of horses may reduce the risk of disease transmission
during transport. Ideally, these should be booster vaccinations but, if
horses have not been vaccinated previously, then sufficient time shouldbe allowed before transport for both primary and secondary
vaccinations to produce adequate immunity.

4.

When mixed loads (eg breeding and competition horses; pregnant andnon-pregnant mares) are unavoidable, give careful consideration to
the categories of horses which are transported together so as tominimise the disease risk (eg risk to pregnant mares of EHV-1 infection;risk of spread of EVA infection).

5.

Horses should only travel if they are considered fit to do so by aveterinary surgeon.

6.

Sick animals should not be transported except when they are travellingto obtain veterinary treatment. If transport of such horses is unavoidable,
they must not be put in mixed loads without the consent of otherowners (or those authorised to act on their behalf) of horses in that load.
Veterinary advice should be taken.

7.

If horses or their in-contacts are ill on, or shortly after, arrival at theirdestination, veterinary advice should be taken and the sick horses
isolated if necessary. The transport operator should be informed at onceand should then inform other clients with animals in the same load.

8.

Facilities should, if necessary, be made available for cleaning/mucking
out of lorries at premises where loading/unloading stops are made.

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APPENDIX 8
Information on vaccines available in the UK
Brand name

Manufacturer

Licensed

Artervac*

Fort Dodge

As an aid in the prevention of EVA

Duvaxyn EHV 1,4Fort Dodge

As an aid in the prevention of abortionand respiratory disease caused by
EHV-1 and EHV-4

Equilis ResequinIntervet UK Ltd

As an aid in the prevention of respiratory
disease caused by EHV-1 and EHV-4
and equine influenza

Veterinary advice should be sought on the choice, timing and administration ofany vaccine.
*Veterinary surgeons and horse owners should be aware that the current
datasheet requirement for the only inactivated EAV vaccine used in Europe
presently is for 6 monthly boosters and NOT 12 monthly (annual) boosters as waspreviously the case for this vaccine. This has been the requirement since April
2005, when the vaccine was granted a full licence by the Veterinary Medicines
Directorate. Non-compliance with this booster interval requirement may
necessitate investigation of the viral shedding status of stallions by Defra under
the Equine Viral Arteritis Order 1995.
Vaccination is recommended as one means of aiding the prevention of disease.
The listing of vaccines above is for information purposes only and does not imply
endorsement of the products by the HBLB, its Veterinary Advisory Committee or
Sub-Committees. The information given is accurate at the time of printing.

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APPENDIX 9
Further reading and relevant publications
Infectious Diseases of Horses Order
Reference: 1987 No. 790. Obtainable from HMSO.
www.legislation.gov.uk

Equine Viral Arteritis Order
Reference: 1995 No. 1755. Obtainable from HMSO.
www.legislation.gov.uk

Equine Veterinary Education
1996 Volume 8 (3) 166–170. Obtainable from Equine Veterinary Journal Ltd,
Mulberry House, 31 Market Street, Fordham, Ely, Cambs CB7 5LQ.
www.evj.co.uk

BEVA Guide to the use of Artificial Insemination in Horse Breeding
Obtainable from the British Equine Veterinary Association, Mulberry House, 31Market Street, Fordham, Ely, Cambs CB7 5LQ.
www.beva.org.uk

Newmarket Stud Farmers Association Breeding Regulations
Obtainable from Rustons and Lloyd, 136 High Street, Newmarket, Suffolk
CB8 8JP.
www.nsfa.org.uk

National Trainers Federation Code of Practice for Infectious
Diseases of Racehorses in Training
This guide for trainers and their veterinary advisors is available from the NTF.
www.racehorsetrainers.org

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APPENDIX 10
Glossary of terms used in the Codes ofPractice
AerobicallyIn the presence of oxygen

Antibody

Protective protein produced by the body inresponse to the presence of a virus or bacteria

CervixNeck of the uterus opening into the vagina

Clitoris

A body of tissue found just inside the vulva

EDTA blood

Blood sample which has been prevented fromclotting by the addition of ethylenediamine tetraacetic acid (EDTA)

Endometrium

Tissue that forms a lining inside the uterus

Genitalia

Genital (ie reproductive) organs

Guttural pouch

Two large sacs connected to the tube (eustachian)between the horse’s ear and throat

Heparinised blood

Blood sample which has been prevented fromclotting by the addition of heparin

Immunofluorescence

A test that uses a specific antibody and a fluorescentcompound to detect a specific organism

Jaundice

Condition in which a yellow colour can be seen in
the mouth, eye and vagina

MicroaerophilicallyIn the virtual absence of oxygen (10% of carbon
dioxide)Nasopharyngeal swab

Swab taken from the nose and throat

Oestrus/oestrous period

In heat or in season

Placenta

Membrane which surrounds the fetus in the uterus

Polymerase chain reaction (PCR) A laboratory technique that produces multiple
copies of the genetic material of a micro-organism
contained within a clinical sample (eg swab). The
technique amplifies the genetic material so thateven tiny amounts can be detected, thereby
permitting diagnoses of infections to be made.
UrethraTube through which urine is discharged from the
bladder

Uterus

Womb

Venereal disease

A sexually transmitted disease

Vulva

External opening of the vagina

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codes.hblb.org.uk
Codes of practiceLaboratory approval scheme

racehorsehealth.hblb.org.uk
Research projects

www.hblb.org.uk
Infectious disease and equine influenza programmes
Research and clinical scholarships