Recommendations for the health monitoring of rodent and rabbit ...

Recommendations for the health monitoring ofrodent and rabbit colonies in breeding andexperimental units

Recommendations of the Federation of European Laboratory AnimalScience Associations (FELASA) Working Group on Health Monitoring ofRodent and Rabbit Colonies accepted by the FELASA Board ofManagement, 9 June 2001

FELASA Working Group on Health Monitoring of Rodent and RabbitColonies: W. Nicklas (Convenor), P. Baneux, R. Boot, T. Decelle,A. A. Deeny, M. Fumanelli & B. Illgen-WilckeFELASA, BCM Box 2989, London WC1N 3XX, UK

1 Preamble

These recommendations are primarilyintended to standardize health monitoringprogrammes and reporting. In this way theymay also help to standardize the micro-biological quality of animals. However, it isnot a requirement of these recommendationsthat animals tested are free from all of themicroorganisms listed.

Health monitoring is a complex issue.Therefore, it is recommended that a personwith suf®cient understanding of theprinciples of health monitoring (FELASACategory D, Nevalainen e t a l. 1999 ) be

identi®ed as the individual responsible fordevising and maintaining a health monitor-ing policy for the facility.

It should be noted that health monitoringis not con®ned to laboratory reporting. Thereshould also be engendered a culture of com-munication between animal technicians,facility managers, veterinarians andresearchers so that observed abnormalities inbreeding animals and experimental data canrapidly be evaluated and appropriate actiontaken.

Animals that are standardized as much aspossible are important prerequisites forreproducible animal experiments.

WORKING PARTY REPORT

# Laboratory Animals Ltd. Laboratory Animals (2002) 36, 20–42

Contents

1 Preamble 202 General considerations 213 Risk of introducing unwanted microorganisms 224 Frequency of monitoring and sample size 235 Test methods and samples 266 Health monitoring: agents to be monitored 277 Reporting test results 288 References 299 Appendices

Appendix 1: Some points to consider when monitoring animals fromexperimental units or various housing systems 31

Appendix 2: Comments on agents 32Appendix 3: Health monitoring reports 38

Microbiological standardizat ion aims to pro-duce animals that meet preset requirementsof microbiological quality, and to aid in themaintenance of this quali ty during experi-ments. Health monitoring is therefore anintegrated part of any quality assurance sys-tem, e.g. good laboratory practice (GLP), theaccreditation programme of the Associationfor Assessment and Accreditation of Labora-tory Animal Care International (AAALAC)(www.aaalac .org), or the International Stan-dards Organization (ISO). In addition toinfections (Bhat t e t a l. 1986, Lussier 1988,Nicklas e t a l. 1999 ), other exogenous (envir-onmental) and genetic factors and theirinteractions may in¯uence the suitabi lity ofan animal for research.

Outbreaks of infectious diseases in ani-mals occur from time to time and empha-size the need to consider the microbiologicalquality of the animals concerned. Severalgroups of microorganisms (viruses, myco-plasmas, bacteria, fungi, and parasites) areresponsible for infections in rodents andrabbits. Most infections do not lead to overtclinical symptoms (disease), and may belatent. Thus, an absence of clinical mani-festations of infection has only limiteddiagnostic value. However, these latentinfections can have a considerable impactupon the outcome of animal experiments.There are numerous examples of the in¯u-ences of microorganisms on the physiologyof the laboratory animal and hence of theinterference of latent infections on theresults of animal experiments (behaviour,growth rate, relative organ weight, immuneresponse) (Nicklas e t a l. 1999 ). All infec-tions, apparent or inapparent, are likely toincrease biological variability and henceresult in an increase in animal use. Infectionin animals can also lead to contamination ofbiological materials such as transplantabletumours and other tissues, cell lines andsera (Nicklas et a l. 1993 ) and may also leadto contamination of animals. Some of themicroorganisms that may be present inlaboratory animals can also infect humans(zoonoses). For all these reasons, it is of vitalimportance that each institution establishesa laboratory animal health monitoringprogramme.

This report proposes a scheme for healthmonitoring of laboratory animal breeding andexperimental colonies, with the intention ofharmonizing procedures primarily amongcountries associated with FELASA, but alsoworldwide. The use of the recommendationswill be facilitated by a basic knowledge ofmicrobiological standardization and diseasesof laboratory animals, and we thereforerecommend the following texts relevant tothese subjects (National Research Council1991, Boot et a l. 1993, van Herck e t a l. 1993,Weisbroth e t a l. 1998, Percy & Barthold2001 ).

The present recommendations replaceprevious FELASA recommendations for thehealth monitoring of breeding and experi-mental colonies of rodents and rabbit s (Krafte t a l. 1994, Rehbinder et a l. 1996 ).

This document is aimed at all breeders andusers of laboratory animals (animal faci litymanagers, veterinarians and scientists usinganimals for experimental purposes).

These recommendations will be underperiodical review and amendments will bepublished as necessary (www.felasa.org).

2 General considerations

These recommendations constitute a com-mon approach for health monitoring oflaboratory animals and the reporting ofresults. Actual practice may differ from theserecommendations in various ways dependingon local circumstances, such as researchobjectives, local prevalence of speci®c agents,the existence of national monitoringschemes, regulations related to the produc-tion of sera and vaccines (e.g. EU Note forGuidance III 1993, ICH Harmonised Tri-partite Guideline 1997). Health monitoringschemes must be tailored to individual andlocal needs. However, quality aims must beclearly de®ned and an appropriate system ofpreventive hygienic measures (e.g. barriersystems) developed to meet those aims.Finally, a health monitoring programmeshould be establ ished in every facility todemonstrate whether the quality aims havebeen met by monitoring the effectiveness ofthe preventive measures.

Recommendations for the health monitoring of rodent and rabbit colonies 21

Laboratory Animals (2002) 36

The term ’unit’ is here understood todescribe a self-contained microbiologicalentity. Space and traf®c of personnel andgoods essentially separate units. Dependingon the actual measures taken and on theprofessional judgement of the personresponsible for the health monitoring pro-gramme, a unit might be:

the total facil ity;various animal rooms within differentbuildings which are attended by the samegroup of people (without special preven-tive measures);a classical barrier facil ity with variousrooms (irrespective of how many speciesor strains are maintained within it );an animal room that is protected bypreventive measures, such as changingclothing;an isolator or isolators between whichanimals are freely transferred with nospecial preventive measures, using proce-dures that are appropriate to the use ofisolators;an individually ventilated cage (IVC),which is opened only within a laminar¯ow cabinet using procedures that areappropriate to the use of IVCs.

A b re ed ing unit is here understood as aself-contained microbiological entity inwhich animals are bred for scienti®c pur-poses. This means that only those personsthat are involved in housing and breedinganimals have access to the unit. On rareoccasions animals may be introduced, butonly after following strict measures formicrobiological security. Only a very fewexperimental materials (chemicals, drugs,biological materials) are necessary in abreeding unit (e.g. for genetic monitoring).

An expe rim enta l unit is here understood asa self-contained microbiological entity inwhich animals are housed or used for scien-ti®c experiments. Usually, introduction ofanimals from outside sources (commercialbreeders, institutional breeding units,experimental units) is necessary. Additionalpersonnel must have access to conductexperiments, and different kinds of experi-mental materials have to be introduced intoan experimental unit. In addition, breeding of

laboratory animals might be performed insuch a unit.

Preventive measures that reduce the spreadof infection between animal rooms, isolatorsor IVCs may eventually result in splitt ing amicrobiological unit into several units thathave to be monitored separately.

Depending on the judgement of the personresponsible for health monitoring, the totalfacility may be considered as multiple unitsor a single unit. Therefore, different mon-itoring programmes may be necessary in thesame facility.

The cost of preventive measures and healthmonitoring may seem high, but is very lowin relat ion to the total cost of the researchproject and is a fully justi®ed means of en-hancing the reliability of data generated inanimal experiments.

Within the institution, there should be adocumented health monitoring policy and adocumented policy for the introduction ofanimals and biological materials (qualitysystem).

Additional investigat ions may be deemednecessary. Should these indicate the presenceof an agent which, although not listed inthese recommendations, is suspected ofbeing important, this agent should be men-tioned in successive reports and treated as arelisted agents.

3 Risk of introducing unwantedmicroorganisms

The risk of inadvertently introducing micro-organisms (viruses, bacteria, fungi and para-sites) into breeding units is generally lowerthan for experimental units. Introduction ofunwanted microorganisms is mainly due toone or more of the following factors: animals,biological materials, equipment and staff(Boot e t a l. 1993, Nicklas 1993).

Anim a ls

Experimental units usually contain variousanimal species and strains, originating fromvarious sources. It is recommended thatanimals to be introduced are from sourcesthat follow at least these FELASA healthmonitoring recommendations. This, however,

22 FELASA Working Group on Health Monitoring of Rodent and Rabbit Colonies


may not be possible, for example, in the caseof mice of transgenic strains that cannot beobtained from commercial sources. In thesecases, rederivation, quarant ine or other formof risk management of animals from suspectsources should be considered.

Bio logica l m a te ria ls

The use of biological materials such as cells,sera, ES cells, and sperm derived fromanimals may result in the introduction ofunwanted agents (Petri 1966, Collins & Par-ker 1972, Bhatt e t a l. 1986, Nicklas et a l.1988, Nicklas e t a l. 1993, Dick et a l. 1996,Lipman e t a l. 2000 ). It is recommended thatbiological materials be considered as con-taminated and that animal experiments beperformed under conditions of strict con-tainment (isolation), unless the biologicalmaterials have been tested and found free ofcontamination.

Pe rsonne l

The importance of research staff and animalcare staff to the microbiological integrity ofan animal unit should not be under-estimated. Personnel may act as effectivecarriers of infections from contaminated tonon-contaminated units (La Regina e t a l.1992, Tietjen 1992 ). Microorganisms may becarried in the hair, on the hands and on theclothing of personnel who have been in con-tact with infected animals. It is recom-mended that facilities establish a quarantinepolicy for personnel to minimize the risk ofthem acting as unwitting vectors of infec-tion. Furthermore, it is recommended that apolicy for entering animal facili ties also beestabl ished.

It should be remembered that animals areusually infected and capable of transmittinginfection before showing clinical signs andcertainly before producing antibodies.Therefore personnel or equipment movingwithin the unit, i.e. between rooms or othersubunits of the whole unit, can act as vectorsor the source of an infection before there isany indication of its presence.

Most infections will persist in the unitwhen susceptible animals are continuouslybeing introduced. The infectious cycle can,

however, be interrupted by removing allanimals from a unit at the end of experi-ments and cleaning and disinfecting animalrooms before new animals are admitted (’allin±all out’ system). If such procedures areapplied to short-term experiments (of lessthan 6 weeks), the risk of spreading theinfection is reduced.

4 Frequency of monitoring andsample size

Colonies should be monitored at least quar-terly. Depending on local circumstances andneeds, more frequent monitoring may becarried out for a selection of some frequentlyoccurring agents that have a serious impacton research.

Sick and dead animals should be submittedfor necropsy. These animals should beexamined in addit ion to those alreadyscheduled for routine monitoring. The out-come of the necropsy may prompt anincrease in the sample size and frequency ofmonitoring.

As the question of host speci®city ofinfections is not fully understood, in animal(microbiological) units containing more thanone animal species, each species must bescreened separately, according to the testschedule. Similarly, there may be strain dif-ferences in susceptibility to infection andserological response to agents. Therefore, ifmore than one strain of a species is present,all strains should be screened and each strainshould be monitored at least once a year,where possible.

In microbiological units consisting of twoor more rooms or subunits, the sampleshould comprise animals from as manyrooms or subunits as possible.

To detect a single infected animal in apopulation at a de®ned con®dence level, thenumber of animals examined (the samplesize) is inversely proportional to the percen-tage of uninfected animals (ILAR 1976, Can-non & Roe 1986 ). To increase the con®dence,the sample size needed to detect an infectionthen increases substantially. The formula isapplicable only in populations of at least 100animals, if the infection is randomly dis-tributed in the unit and if the animals are



randomly sampled (Table 1). The prevalenceof an infection may however be dependent onage and sex.

Therefore, a sample size of at least 10animals per microbiological (breeding andexperimental) unit is recommended. How-ever, note that infections having a prevalenceof less than 30% may not be detected with a95% con®dence level. The detection rate fora given infection depends on the test methodemployed. Seromonitoring methods oftenmeasure higher prevalences than directmethods that detect the presence of (parts of)the microorganism. Using seromonitoring,the level of con®dence may therefore beincreased by screening the same number ofanimals.

Due to the higher risk of infection inexperimental colonies, smaller numbers ofanimals are sometimes examined at higherfrequency. Theoretically, this procedure willreveal more actual data on the status of acolony and in most cases will help to detectinfection earlier, but a decrease in sample

size will lead to a decrease in the likelihoodof detecting infections with low prevalence(Table 1).

Sentine l anim a ls

In some experimental units and colonies ofgenetically modi®ed or immunode®cientanimals, there may be an insuf®cient num-ber of animals available for health monitor-ing. It may also be inappropriate to carry outhealth monitoring in such colonies (forexample, serological testing of immunode®-cient animals may be misleading). Healthmonitoring may then be carried out on sen-tinel animals, which act as surveillancesubstitutes. However, the use of sentinelsmay not be covered by the ILAR formula(ILAR 1976 ) for the sampling of animalcolonies.

Sentinel animals must be free from allagents to be monitored; for example whenusing sentinels to monitor immunode®cientanimals, the sentinels must be initially free

Table 1 Calculation of the number of animals to be monitored

Diseases with an infection rate of 50% or more (Sendai, MHV) require far fewer animals to detect their presencethan diseases with low infection rates.

Assumptions

1. Both sexes are infected at the same rate2. Population size > 100 animals3. Random sampling4. Random distribution of infection

The sample size is calculated from the following formula:

log 0:05log N

ˆ Sample size

N ˆ percentage of non-infected animals0.05 ˆ 95% con� dence level

Relation of sample size to prevalence rate

Sample sizes at different con� dence levelsSuspected prevalence rate (%) 95% 99% 99.9%

10 29 44 6620 14 21 3130 10 13 2040 6 10 1450 5 7 10

Example: 10 animals should be monitored to detect at least one positive animal if the suspected prevalence rate of aninfection is 30% (con� dence level: 95%)



from Pne um ocyst is ca rinii. In long-termexperiments, sentinels may be housed withthe experimental animals from the outset toguarantee that the minimal sample size willbe available throughout the whole period ofthe experiment. Alternatively, sentinels maybe introduced periodically to obtain a con-stant update of current infections. Whenshort-term experiments or experiments inmultipurpose units are performed, the unitcan be restocked repeatedly. In this case,sentinels removed for monitoring can easilybe replaced during restocking with experi-mental animals from time to time. Sentinelanimals, used in an animal room, should bedistributed on different cage racks andhoused in open cages among the experi-mental animals for at least 6 weeks. If bothstocks are handled similarly, health mon-itoring data obtained from sentinels will berepresentative of the microbiological statusof all experimental animals of that speciesheld within the unit. Provided that the ani-mals in the general population are in opencages, exposure of sentinels to possibleinfectious agents might be enhanced by put-ting them into open cages throughout theunit in locations where possible exposure toinfectious agents is known or thought to bemaximal. The transmission of infectiousagents may be further enhanced by exposingthe sentinel animals to soiled bedding, waterand feed taken from the cages of the experi-mental animals, and by exposing sentinelanimals directly to experimental animals byplacing them in the same cage. Note, how-ever, that some agents, for example Sendaivirus (Artwohl e t a l. 1994) and CAR bacillus(Cundiffe et a l. 1995 ), may not be transmittedsuccessfully using dirty bedding. Immuno-de®cient strains that are particularly prone tospeci®c infections might be used for detec-tion of some viral, bacterial and protozoal

infections. However, immunode®cientanimals may not produce an adequateimmune response and are thereforeunsuitable for serology. It should be notedthat animals used in this way may act asenhanced transmitters of infection and maythemselves be a hazard to the animals forwhich they act as sentinels because they mayshed pathogenic organisms as a result of theirpersistent infection.

Preventive measures which reduce thespread of infection between animal roomswithin a unit may eventually lead to thecreation of different microbiological unitsthat contain so few animals that the ILARformula (ILAR 1976) is no longer applicable.Similarly, isolators and IVCs may have suchsmall population sizes that samplingaccording to the ILAR formula (ILAR 1976 ) isnot possible. In such cases, smaller samplesizes (e.g. 3±5 animals per sampling) arerecommended if an appropriate sentinel pro-gramme is used which leads to an increasedprobability of agent transmission to sentinelanimals. It is dif®cult to formulate recom-mendations to cover all of the circumstancesin which isolators and IVCs are used. How-ever, some suggestions are given inAppendix 1.

The recommended minimum samplingfrequency, age and number of animals to besampled are summarized in Table 2. It shouldbe noted that animals of other ages might bemore appropriate for the detection of speci®cagents (e.g. < 8 weeks for the detection ofSpiro nuc le us sp.). For monitoring of rabbit s,samples may be taken that do not involve thekilling of animals (e.g. blood or serum sam-ples, swabs from nose, vagina or prepuce,faecal samples) but as this may be less sen-sitive than testing fresh samples from sacri-®ced animals, a larger sample size should bechosen.

Table 2 Recommended minimum frequency of monitoring and sample size for rodent and rabbit units

Sampling No. offrequency Age animals Virology Bacteriology Parasitology Pathology

Every3 months

> 8 weeks 10 ‡ ‡ ‡ ‡



5 Test methods and samples

(1) Diagnostic laboratories should follow aquality system which implies, among otherrequirements, the existence of detailed writ-ten procedures. This will be the case if test-ing is done in compliance with theInternational Standards Organization (ISO)9000 series of norms. However, FELASAadvocates accreditation of diagnostic labora-tories according to ISO 17025 [formerly Eur-opean Norm (EN) 45001], in which specialemphasis is placed on competency of thestaff, validation of (in-house) test methods,and participation in inter-laboratory testingprogrammes (Homberger e t a l. 1999 ). Profes-sional competency is of fundamental impor-tance for pre- and post-analytical advice ontesting and interpretat ion of test results. It istherefore recommended that testing be per-formed under supervision of staff carrying anacademic degree in veterinary medicine,medicine, microbiology or equivalent, whohave additional experience in laboratoryanimal diagnostics and laboratory animalscience at the level of FELASA category D(Homberger et a l. 1999, Nevalainen et a l.1999).

(2) Test m e thods : the presence of infection ina population can be detected by a variety ofdirect methods by which the agent or parts ofit are detected, and by indirect methods, suchas serology in which antibodies to infectiousagents are detected. Direct methods are alsoused in disease diagnostics. The use of asuitable test method does not necessarilyimply a reliable test outcome. Experienceshows that results obtained from differentdiagnostic laboratories may vary con-siderably.

(3) Samples should be taken from randomlyselected individual animals or sentinels andnot pooled.

(4) Viro lo gy : serology is the method of choicefor monitoring viral infections in animals,and is also used to test animals that are usedin antibody production tests (see Section 6.4).Suitable test methods include the enzymelinked immunosorbent assay (ELISA), theindirect immuno¯uorescence antibody test

(IFA) and the haemagglutination inhibition(HI) test. In general, ELISA and IFA are moresensitive than HI and so should be used asprimary tests. The speci®city of the tests isprimarily determined by the antigen chosenand the methods used for antigen preparation(puri®cation etc). ELISA and IFA, for exam-ple, measure cross-reacting antibodies tovarious parvoviruses, whereas HI is speci®cfor the virus (e.g. MVM and Toolan’s H-1virus). The immunoblot technique (Westernblot) is not suitable as a test for routinescreening. The major drawback is that thetechnique is labour- and cost-intensive.However, Western blot is highly speci®c andsensitive and can be used to con®rm ques-tionable results. The presence of LDV (themost frequent contaminant of biologicalmaterial of mouse origin) can be determinedby testing mice injected with the material foran increase in the plasma level of lactatedehydrogenase enzyme, or by using a poly-merase chain reaction (PCR) test on thematerial itself.

(5) Bacte rio lo gy : bacteria are cultured fromsamples taken from the upper respiratorytract (nasopharynx, trachea), intestinal tract(caecal contents or faeces) and genitals (pre-puce/vagina). As such samples containnumerous non-pathogenic bacteria, selectivemedia should be used in combination withnon-selective media whenever possible tofacilitate the isolation of the more fastidiousbacteria. The culture of some fast idiousbacteria requires the use of enriched media.Agar media should be incubated underaerobic conditions. Addition of CO2 ormicroaerophilic conditions may increasethe likelihood of isolating some species.Identi®cation of unwanted bacteriashould proceed to the species name, e.g.Coryneb acte rium k utsche ri. In some cases,involvement of specialized reference labora-tories should be considered. Commonly usedkits for identi®cation of human and veter-inary pathogenic bacteria are sometimes notsuitable to correctly identify bacterial strainsfrom laboratory animals e.g. Pasteurellaceaeand Citro b a cte r rodentium . Molecularmethods (e.g. PCR) may be used for detectionand identi®cation.



Culture techniques are usually used for thedetection of most bacterial agents. Ser-ological methods (mainly ELISA and IFA)exist for the detection of antibodies to var-ious bacterial pathogens (Boot 2001 ) but thereis a higher risk of false positive reactions(compared to viruses) due to their complexantigenic structure. Molecular biologicalmethods also exist for the detection of somebacteria.

(6) Pa ra sito logy : The pelt should be examinedfor evidence of ectoparasites. Wet prepara-tions of the large and small intestines andfaeces should be examined for evidence ofintestinal endoparasites. It should be notedthat older animals may be less suitable formicroscopic examination because ofincreased resistance to parasites with age.Identi®cation of parasites should proceed asfar as possible to the species name. Ser-ological methods exist for the detection ofantibodies to some parasites such asEncepha lito zoon cuniculi . Serological ®nd-ings should be con®rmed by appropriatealternative test methods.

(7) The choice and preparation of antigenused primarily determines the speci®city andthe sensitivity of serological tests. The pre-sence of antibodies in animal sera is only anind ica tor of previous or current infection.Positive results should be con®rmed by othermethods such as culture, PCR, histopathol-ogy or another serological method. It is alsoadvised that positive results be con®rmed byanother laboratory. The results should also becon®rmed by repeated testing/sampling fromthe animal colony. In the case of con¯ictingresults between laboratories, ®nal diagnosiscan only be made on the basis of testing byother than serological methods. This isapplicable to all groups of agents. Serologicaltests can differ greatly in sensitivity andspeci®city. Together with the (sero) pre-valence of the infection, both test propertiesdetermine the predictive value of a positiveand a negative test (Tyler & Cullor 1994 ).

Further, when a number of sera is sub-jected to a battery of serological tests, somefalse positive test results must be expected,even when tests are highly speci®c e.g. 95%

(Tyler & Cullor 1994, Jacobson &Romatowsky 1996 ).

(8) Pa tho lo gy : A full routine necropsy todetect the presence of gross abnormalit iesshould be performed to include examinationof: skin, oral cavity, salivary glands (rat only),respiratory system, aorta (rabbit only), heart,liver, spleen, gastrointestinal tract, kidneys,adrenals, urogenital tract (including testes),and lymph nodes. The aetiology of altera-tions in tissues and organs should be furtherinvestigated by histopathology and micro-biology, as appropriate. Pathology, includingimmunohistochemistry and molecular tech-niques, may be suitable to detect infections.

6 Health monitoring: agents to bemonitored

The viruses, bacteria (including myco-plasmas) and parasites to be monitored arelisted for each animal species in Appendix 3(= FELASA Approved Health MonitoringReports). Rederived and restocked breedingcolonies should be monitored at least for theagents listed for the appropriate species.Thereafter, breeding colonies should betested for the most relevant infections listedat least quarterly. The remaining agentsshould be monitored at least annually.

A similar monitoring approach is advisedfor experimental animal colonies in whichexperiments are continuously performedwithout application of the so-called ’all in±allout’ system (at least quarterly).

Monitoring for additional agents and theirdeclaration in a health report is advised underspeci®c circumstances, e.g.

when associated with lesions;when associated with clinical signs ofdisease;when there is evidence of perturbat ion ofphysiological parameters or breeding per-formance;when using immunode®cient animals.

Biological material must be evaluated for thepresence of relevant agents, including lactatedehydrogenase elevating virus (LDV). This isusually done using mouse, rat or hamster



antibody production tests (MAP, RAP, HAP).Molecular testing may be used as an alter-native method. Animals that are to be usedin MAP, RAP or HAP tests must be free fromall the infections listed in the appendices forwhich the biological material will be tested.Such tests should be performed under max-imal containment conditions (e.g. an isolator)in order to protect other animals in thefacility, and to avoid infection of the testanimals from other sources.

7 Reporting test results

(1) Health monitoring data should be madeavailable to those researchers using the ani-mals. The data are part of the experimentalwork and should therefore be evaluated fortheir in¯uence on the results of experiments,and included in scienti®c reports and pub-lications as part of the animal speci®cation.

(2) In order to easily compare monitoringreports from different breeders and users, theFELASA approved health monitoring reportmust be used to present health status infor-mation on animals and biological materials.Monitoring reports have been developed forall common species of laboratory rodents andrabbits (Appendix 3).

(3) The health monitoring report of a unitshould include the following information:

Unit designation and description (non-barrier, barrier, IVC, isolator).Identi®cation of all species and strainspresent within the unit for which thereport is valid, and the date of issue of thereport.Positive results of other species heldwithin the same unit should be reported.All viruses, mycoplasmas, bacteria, andfungi for which monitoring is recom-mended (ordered alphabetically) and ecto-and endoparasites identi®ed to the specieslevel.Date of latest investigation (per species),method used, designation of antigen usedin serology, the name of the testinglaboratory.Results of latest investigation and 18months cumulative results of all

investigations: number of positive ani-mals/number of animals examined.Results of testing not included in thestandard health monitoring programmeshould be added as supplementary infor-mation (for example disease diagnoses).Results of pathological examinationsshould be recorded as: Pathologicalmacroscopic lesions were/were notobserved in the organs examined.Pathological changes should be listedseparately for each species and strain.

(4) It should be emphasized that negativeresults mean only that (antibody activity to)the microorganism monitored has not beendemonstrated in the animals screened by thetest(s) used. The results are not necessarily are¯ection of the status of all the animals inthe unit.

(5) An agent must be declared present if it isidenti®ed in one or more of the animalsscreened. Essentially the same is true ifantibodies are detected, but positive ser-ological results must have been con®rmed(see 5.7).

(6) Agents known to be present need not bemonitored at subsequent screens providedthat they are declared in the health report.The unit must continue to be reported aspositive (at subsequent screens) until theorganism has been eradicated, for example bymeans of rederivation or restocking by ani-mals from another source. Eradication of theinfection(s) will be con®rmed by subsequenttesting according to FELASA recommenda-tions. If the animals have been treated in anyway, for example by vaccination, or anthel-mintic therapy for pinworm infections, thismust be stated on the health monitoringreport.

(7) An agent may be considered to be eradi-cated if all results of monitoring done inaccordance with FELASA recommendations(i.e. with appropriate and sensitive methods,representative sampling) during 18 monthsafter the last positive results are negative.This represents at least 6 subsequent screensdone quarterly.



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9 Appendices

Appendix 1 Some points to considerwhen monitoring animals fromexperimental units or various housingsystems

This appendix is to be used in conjunctionwith the main document and should not beused as a stand-alone document.

Fre q uency o f m onito ring

A similar monitoring programme (frequencyof monitoring, sample size) for breedingcolonies is advised for experimental animalunits if animals are housed in open cagesunder barrier conditions or conventionallyand in units in which animals are introducedonly occasionally or where only long-termexperiments are performed. More frequentmonitoring is necessary if animals or

biological materials are frequently intro-duced into the unit. Infected animals on thesite also increase the risk of infection.Monthly or even more frequent monitoringmight be advisable in order to obtain reliableinformation on the actual status. In suchcases it is recommended that a minimum of3±5 animals is a suf®cient sample size ofanimals to be monitored per month. Thefrequency of monitoring is dependent on therisk of introducing agents (Table 3).

Results of monitoring are presumed to bevalid for all animals of the same specieswithin the same unit, independent of thetype of experiment.

Sam ple size

Generally, a sample size of 10 animals permicrobiological unit is recommended.

In some units of experimental or geneti-cally modi®ed animals (e.g. transgenicbreeding), there may be insuf®cient numbers

Table 3 Some factors that increase the risk of introducing agents into an experimental unit, thereforerequiring more frequent monitoring

High risk:

Multipurpose units with various kinds of experiments

Frequent introduction of animals ( > 16per month)

Frequent entry of research personnel in addition to animal care staff

Frequent change of personnel working in the unit

Introduction of animals from different breeding units (from one or several breeders)

Introduction of biological materials (e.g. sera, tumours, tissues, (ES) cells) originating from the same animal speciesthat are housed in the unit

Infected animals on the site

Medium risk:

Occasional introduction of animals

One or few types of experiments

Long-term experiments (only occasional introduction of animals)

‘All in–all out’ system

Introduction of chemicals only, no biological materials



of animals available for health monitoring.Serologic monitoring of immunode®cientand many strains of genetically modi®edanimals may yield false-negative resultsbecause these animals do not always producesuf®cient amounts of antibodies. Often,small populations have to be monitored (e.g.isolator, IVC). In such cases random sam-pling may not be possible or reasonable (seeTable 4). The formula given in the maindocument (Table 1) is therefore not applic-able in many experimental units. In suchcases, smaller sample sizes (e.g. 3±5 animalsper sampling) together with an increasedmonitoring frequency are acceptable if anappropriate sentinel programme is usedwhich enhances the probability of agenttransmission to sentinel animals.

Animals which show clinical signs unre-lated to the experiment should be necropsiedand subjected to histopathology and to amicrobiologic, parasitologic and serologicexamination independent of scheduledtesting.

Monito ring anim a ls from various housingsystem s

Conventional or b a rrier units do not pose aproblem for monitoring because a suf®cientpopulation size is availabl e. If necessary,suf®cient space is usually available forhousing sentinels. Space might, however, belimited in ®ltered cabinets or rooms, iso-lators or ®lter top cages (static or individuallyventilated cages, IVCs).

If animals housed in ®ltered cab inets orrooms or in iso la to rs are to be monitored, anef®cient sentinel programme (one withappropriate use of soiled bedding and feed) isimportant for increasing the likeliness ofagent transmission to the small number of

sentinels. If germ-free or gnotobiotic animalsare housed in isolators, monitoring for bac-teria (environmental organisms) is moreimportant than monitoring for viruses orparasites due to the higher risk of the formerbeing introduced. Due to space restrictions,only 3±5 animals are usually available forhealth monitoring of isolator-housed ani-mals.

Reliable information on the infection sta-tus in ®lte r top cage s or ind ividua lly venti-la te d cage s (IVCs) is dif®cult to obtain. Ifproperly handled, every cage represents amicrobiological unit, and the system pre-vents the transmission or spreading of agentsbetween cages. Dirty bedding from as manycages as possible must be placed in a separateventilated cage in which sentinels arehoused. The changing of bedding-donorsgives a good insight into the colony status.Other examples of methods for monitoringthat may be considered are the use of contactsentinels and the testing of exhaust ®lters orcage surfaces using PCR.

Appendix 2 Comments on agents

These comments have been added because:

some agents, for which monitoring wasrecommended earlier, were removed fromthe list or the frequency of monitoringwas changed;some new agents have been added.

The information given here should helpreaders of the recommendations to under-stand better why monitoring for speci®cagents is recommended or why changes weremade (as compared to previous recommen-dations). Therefore, very basic information

Table 4 Sampling for health monitoring (see Section 4 of the main document)

Suf� cient No. of animalsper unit Random sampling

Barriers: breeding Available PossibleBarriers: experiment Usually available Usually not possibleIsolators Usually not available Usually not possibleFilter top cages and IVCs No No

IVCs ˆ individaul ventilated cages



is given on most agents. A few references areadded on recently described agents or agentsthat are rarely mentioned in the literature.

However, one should realize that muchinformation, for instance, on the impact, theepizootiology, testing, etc. of several agents iscontroversial. For details, the reader isadvised to consult specialists in the ®eld andthe scienti®c literature.

Bacteria, fungi

Borde te lla b ronch iseptic a : subclinical infec-tion is most frequent in rabbits andoccasionally occurs in guineapigs andrats.

CAR b acil lus : has been implicated in chronicrespiratory disease in mice, rats andrabbi ts, but their role is obscured byfrequent simultaneous infection byMycoplasma and viruses. Cage to cagetransmission of the infection is slow, andCAR bacilli are usually not transmitted tosentinels by dirty bedding.

Chlam yd ia spp .: infections are usuallypersistent and subclinical. C. psitta c i maycause inclusion conjunctivitis and pneu-monia in guineapigs. C. tra chom a tismouse biotype may under certain cir-cumstances cause pneumonia in mice butthe signi®cance is low.

Citrob acte r rodentium : was formerly knownas ’Citro b a cter fre und ii 4280’. It has nowbeen characterized, and taxonomic studiesshowed that it is de®nitely a separatespecies (Schauer e t a l. 1995 ). Presence ofthe bacterium has been reported to lead totransmissible colonic hyperplasia in mice.

Clo strid ium pilifo rm e : The causative agentof Tyzzer’s disease (formerly Bacillu spilifo rm is ) does not grow on bacterialculture media. Screening for Tyzzer’sdisease by histopathology is insensitive.Positive serological reactions occur fre-quently without clinical signs of diseaseand may be indicative of recent act iveinfection. However, the interpretat ion ofserological testing is currently controver-sial. The suitability of PCR is at presentunclear. Immunosuppression of a signi®-cant number of the population has been

used to demonstrate the presence of thisagent in animal colonies.

`C o ryne b acte rium b ovis ’: a bacteriumresembling C. b ovis is the aetiologicalagent of ’scaly skin disease’ or ’coryne-bacterial hyperkeratosis’ of nude mice(Clifford et a l. 1995, Scanziani e t a l. 1997 ).The clinical disease in nude mice candisappear spontaneously, but high mortal-ity is possible, especially in newborns.C. b ovis may also cause lesions in micewith fur, e.g. SCID mice (Scanziani et a l.1998 ). While monitoring is not mandatoryin immunocompetent mice, they maycarry this agent. Monitoring is recom-mended in immunode®cient mice.

Coryneb acte rium k utsche ri: subclinical andsymptomatic infection (pneumonia) hasmainly been detected in mice and rats.

Derm atophyte s : Microspo rum spp. andTrichophyto n spp. infections (dermato-mycoses) occasionally occur in guineapigsand rabbits. Lesions are rare.

He lic ob acte r spp.: various species of thisgenus have been described since their ®rstisolation from rodents about 10 years ago.At present, there is evidence that somespecies have the potential to induceclinical disease or may have impact onanimal experiments (e.g. H. hepa ticus ,H. b ilis , H. typh lonicus ) (Fox & Lee 1997,Franklin et a l. 1999 ), whereas no sucheffects have been described for otherspecies (e.g. H. rodentium ). Additionalspecies are likely to be described in thenear future, and a general recommenda-tion regarding which agents are to bemonitored can therefore not be givenpresently.

Lawsonia intra ce llula ris : (IntracellularCam pylo b a cte r-like organisms) is a likelycause of proliferative enteritis (wet tail ) inhamsters. Screening is not recommended,as infection is supposed to lead invariablyto clinical disease with characteristiclesions in the intestines.

Le pto spira spp.: Monitoring for these zoo-notic bacteria may be considered iflaboratory animals are at increased risk ofinfection, for instance by contact withwild rodents. Seromonitoring is done byspecialized laboratories. Costs are high



as monitoring for several serotypes isnecessary. Occurrence of Le pto spira spp.in contemporary colonies is unclear.Leptospirosis has however been found in’clean conventional’ mice (Alexander1984 ).

Mycopla sm a spp .: M. pulm onis is at presentthe most relevant species in mice and rats.Screening is usually done by serology, butantibody response varies greatly betweenmouse and rat strains. Culture is dif®cultbut may additionally detect various othermycoplasma species. Detection ofMycopla sm a spp. by PCR is possible.

Pasteure lla cea e : As in the previous FELASArecommendation for experimental units,monitoring for all Pasteurellaceae isrecommended. Pa steure lla pneum otro picadescribes a genetically diverse group oforganisms. It has been shown repeatedlythat different laboratories come to differ-ent conclusions on the same strain ofrodent Pasteurellaceae, and commercialidenti®cation kits do not identify themproperly.

Pne um ocystis ca rinii : is an important fungalpathogen in immunode®cient animals andmay lead to clinical disease or death.Monitoring is recommended for rat andmouse strains with inherited or inducedimmunode®ciency (e.g. Foxn1nu,Prk dc scid, Rag1tm1Mom ).

Pseudom ona s a e rugino sa : the signi®cance islow in immunocompetent animals, but itmay cause clinical disease in immunode-®cient or immunosuppressed hosts.

Sa lm one lla spp.: infrequently found in allanimal species. Infected rodents and otherhosts, including personnel, may be sourcesof infection. Such risks are especially greatin multipurpose research institutes thathouse animals of varying pathogen status.

Sta phylo co ccus aureus: This bacterial spe-cies is ubiquitous in rodent populationswhere there is direct contact betweenhumans and animals and has the potentialto induce clinical signs of disease (e.g.abscesses, wound infections). Exception-ally, other Sta phylo co ccus species mayalso induce clinical signs, at least inimmunode®cient animals (Brad®eld e t a l.1993 ).

Stre pto b a cil lus m onilifo rm is : infectionshave been detected during the last decadesin colonies of mice, rats and guineapigs.Culture of the bacterium from asympto-matic animals is notoriously dif®cult.Quarterly monitoring in rats is recom-mended because this species is the naturalhost.

Stre pto co ccus spp .: (a-haemolyticS. pneum onia e and b-haemolytic otherspecies) rarely induce clinical disease andare important primarily in immunode®-cient animals but may also lead to clinicalsigns in immunocompetent individuals.

Viruses

Coronaviruse s (MHV in mice, RCV/SDAV inrats): occur frequently and are stronglyimmunomodulating. Infections areusually self limiting but may be persistentin immunode®cient animals.

Ectrom e lia virus: recent infections camemostly from contaminated biologicalmaterials (sera, cells) and contact withwild mice and pets. Susceptibili ty andantibody response great ly differ amongmouse strains.

Guine apig ad enovirus: This virus has beenidenti®ed repeatedly as a causative agentof disease or death in guineapigs. Thevirus cannot be propagated in cell culture,and antigen for serological tests is there-fore dif®cult to obtain. Mouse adenovirus(K87 or FL) is commonly used as anantigen to test guineapig colonies forantibodies to guineapig adenovirus, butthere is con¯icting information on thedegree of cross-reactivity between mouseand guineapig adenoviruses and the valid-ity of these tests (Butz et a l. 1999 ).

Guine apig cyto m ega lo virus (GpCMV ˆ Gpherpesvirus type 1): this host speci®cinfection may lead to clinical disease inbreeding females. Vertical transmission ofthe virus is considered common. Seromo-nitoring results can be con®rmed byantigen detection in organs of animalsunder severe immunosuppression. Thereis no cross-reactivity with other herpes-viruses.



Ham ste r pa rvovirus (HPV): weanling andadult hamsters develop clinically silentinfections but infection of neonatal Syrianhamsters may result in severe and oftenlethal disease. Monitoring is recom-mended as soon as an antigen is avai lable.

Hanta viruse s: Wild rodents are naturalreservoirs for this group of zoonoticviruses. Laboratory rats and rat materialhave repeatedly been the source of Seoulserotype Hantavirus infections in researchpersonnel. None of the many other sero-types (e.g. Puumala) has so far beendetected in laboratory animal colonies(Meyer & Schmaljohn 2000 ). Hantavirusinfections in rats are inapparent.

K virus : (Mouse pneumonitis virus): pre-viously annual testing was recommended,but infections have not been reported formore than two decades.

Kilh am ’s ra t virus (KRV, RV): see Parvo-viruses.

Lacta te dehydrogenase e leva ting virus(LDV): infects mice only and is trans-mitted within a population vertically or bydirect contact (blood). The most importantmode of transmission is by experimentalprocedures (injections, animal-to-animalpassages of tumours, microorganisms,parasites, etc.). It is unlikely to be found inbreeding units, but it is an importantcontaminant of biological materials afteranimal passages. It should be included inmonitoring programmes for biologicalmaterials and mice if such materials arepassaged in mice.

Lym phocytic cho riom eningiti s virus(LCMV): Only mice and hamsters areknown to transmit this zoonotic virus, butother species (e.g. rabbits, guineapig, rats)also seem to be susceptible to experimen-tal infection. Detection of enzootic infec-tion in mice by serology may be dif®cult(depending on the mode of infection) dueto immunotolerance.

Minute virus o f m ice (MVM): see Parvo-viruses.

Mouse adenovirus : It was shown that bothstrains of mouse adenovirus do not alwayscross-react in serological tests. Therefore,both strains (FL, K87) should be used asantigens (Lussier e t a l. 1987 ). Positive

reactions have also been found in rats, andit is recommended that rats are alsomonitored.

Mouse cyto m ega lo virus (MCMV): the preva-lence of this virus in contemporarylaboratory mice is thought to be negligibleexcept in instances in which stocks mayhave been contaminated by wild mice.

Mouse hepa ti tis virus (MHV): see Coronaviruses.

Mouse pa rvovirus (MPV): see Parvoviruses.Mouse po lyo m avirus : previously annual

testing was recommended, but infectionshave not been reported for more than twodecades.

Mouse ro ta virus (EDIM): previously annualtesting was recommended. The virus hasbeen found in many mouse colonies inrecent years. Mouse rotavirus does notinfect other species.

Mouse thym ic virus (MTV): previouslyannual testing was recommended, butinfections have not been reported for morethan two decades.

Pa rvoviruses : In addition to well-knownparvoviruses (MVM, KRV, H-1), additionalspecies have been found during the lastdecade (mouse parvovirus, MPV; rat par-vovirus RPV). Different strains exist forthese viruses, and propagation in cellculture is not easily possible. Therefore,antigens are dif®cult to obtain, andonly a few laboratories are able to test forthese agents by speci®c tests (Jacoby e t a l.1996 ).

Pne um onia virus of m ice (PVM): infects miceand rats. Previously monitoring of ham-sters, guineapigs and rabbits was recom-mended, but the virus has not beenisolated from any of these species.

Rab b it ha em orrhagic d isea se virus (RHDV):This highly contagious calicivirus causeshigh mortality in rabbit populations.However, apathogenic caliciviruses existwhich interfere with serological tests(Capucci e t a l. 1996, Chasey 1997 ). Posi-tive serological reactions for RHDV maytherefore be caused by cross-reaction withsuch virus strains. Positive reactionsshould be interpreted with care.

Rab b it ente ric coronavirus: infections seemto occur frequently in rabbitries, but the



virus has not been isolated (hence mon-itoring is not possible).

Rab b it pa rvovirus : infections seem to occurfrequently in rabbit ries. Monitoring isrecommended as soon as an antigen isavailable.

Rab b it po x virus (myxomatosis): monitoringwas recommended earlier, but as thenatural mode of transmission is by insects,the infection is not likely to be found inwell managed laboratory colonies. Diag-nosis can be easily made by clinical signsand by post mortem examination.

Rab b it rotavirus : infection is non persistent.Seromonitoring must be carried out usinga serogroup A antigen (as in mice).

Rat parvo virus (RPV): see Parvoviruses.Rat re spira to ry virus (RRV): this yet unclas-

si®ed virus induces mild to moderate lunglesions (interstitial lymphohistiocyticpneumonia, increased bronchus-asso-ciated lymphoid tissue) in all strains ofrats, usually at an age of 8±10 weeks.Clinical signs have not been reported.Diagnosis is presently based on histo-pathology. Antigens and serological testsare at present not available, and monitor-ing on a broad basis is therefore notpossible (Elwell e t a l. 1997, Riley e t a l.1997, Slaoui e t a l. 1998).

Reovirus type 3: Besides mice and rats,antibodies have been found also inasymptomatic hamsters, guineapigs (forwhich monitoring was recommended ear-lier) and in rabbits, but the virus has notbeen isolated from any of these species.

Senda i virus: rodents (mice, rats) are thenatural host for this virus. Seropositivesamong other species (including man) arelikely to be due to closely related,serologically cross-reacting viruses (e.g.other paramyxoviruses). Since transmis-sion via dirty bedding is not reliable, theuse of cage contact sentinels is recom-mended.

Sia lo dacryoadenit is virus (SDAV)/Rat coronavirus (RCV): see Coronaviruses.

Sim ian virus 5 (SV5): was earlier recom-mended for guineapigs, but no documen-ted infections are known.

The ile r’s m urine encepha lom ye litis virus(TMEV): Positive reactions have been

reported in rats which might be due to ayet uncharacterized virus (’rat cardio-virus’) (Ohsawa et a l . 1998 ). Positive®ndings have also been reported inguineapigs suffering from lameness.

Toolan’s H-1 virus: see Parvoviruses.

Parasites

Am oeb a e (Enta m oeb a sp.): are commensalprotozoans found in the large intestine.Infections are subclinical, and no exam-ples of interference with research havebeen reported. They might, however, be anindicator of hygiene failures or contactwith wild or infected animals.

Cesto de s : most species require an inter-mediate host and are therefore unlikely tobe found in well-managed animal faci l-ities. Some, however, may have a directlife cycle (e.g. Hym eno le pis nana ) byingestion of eggs and have been detected inrodent colonies.

Coccid ia : these host-speci®c protozoans arecommon pathogens in rabbi ts and guinea-pigs and may cause enteritis and death,primarily in young animals. Coccidiainfections may also occur in mice and ratsbut are uncommon.

Ectoparasite s : colonies of laboratory animalsmay severely suffer from ectoparasites(mites, ¯eas, lice, mallophages).

Encepha lito zoon cuniculi : this microspori-dian parasite can occur in all species,mostly in rabbits and guineapigs. It causesmultifocal nephritis and encephalitis(mostly subclinical). Infectious spores areexcreted in urine.

Gia rd ia m uris: causes subclinical infectionin laboratory rodents.

Klo ssie lla sp.: members of this genus arecoccidia and are found in kidney tubulesor endothelial cells of blood vessels inmice (K. m uris ) and guineapigs(K. cob ayae ). The infection is clinicallyoccult but lesions in the kidneys areusually visible macroscopically.

Nem atode s: several species have beenreported from most species of laboratoryanimals. They may colonize differentparts of the intestinal tract (e.g. stomach,liver, caecum, colon) and even the urinary



bladder of rats (Tricho som o id escra ssicauda ). Due to differences in theirlife cycles and different predilection sitesin their hosts, several detection techni-ques (e.g. perianal examination withcellophane tape, ¯otation, wet mount ofcaecum contents) may be necessary todetect or exclude parasitic stages ofpinworms in mice and rats (Syph aciasp., Aspiculuris ) with suf®cientcertainty.

Spiro nuc le us sp.: insuf®cient information isavailable on transmission of these ¯agel-lates between different rodent species(mouse, rat, hamster). They may induce

clinical signs and have impact on varioustypes of experiments.

Toxo pla sm a gondii : monitoring was earlierrecommended, but as infectious forms areexcreted by Felidae only, spread of theinfection within rodent and rabbit colo-nies does not occur.

Trich om onads: at present no evidence existsthat these obviously apathogenic ¯agel-lates have any impact on the physiologicparameters of their host. They are, how-ever, likely to be species-speci®c and thusmight be an indicator of a leak in thebarrier system or of direct or indirectcontact with wild rodents.



Appendix 3 Health monitoring reports

Health Monitoring in Accordance with FELASA recommendations

Date of issue:

Location: Housing: (Barrier/Non-Barrier/IVC/Isolator):

Species: Mouse Strain: (Strain)

Species and strains present within the unit:

Testfrequency

Latesttest date

Latestresults

Testinglaboratory

Testmethod

Historicalresults( 18 months)

VirusesMouse hepatitis virus 3 monthsMouse rotavirus (EDIM) 3 monthsParvovirusesMinute virus of mice 3 monthsMouse parvovirus 3 monthsPneumonia virus of mice 3 monthsSendai virus 3 monthsTheiler’s murine

encephalomyelitis virus3 months

Ectromelia virus AnnuallyLymphocytic

choriomeningitis virusAnnually

Mouse adenovirus type 1 (FL) AnnuallyMouse adenovirus type 2 (K87) AnnuallyMouse cytomegalovirus AnnuallyReovirus type 3 AnnuallyAdditional organisms tested:

Bacteria, mycoplasma and fungiCitrobacter rodentium 3 monthsClostridium piliforme

(Tyzzer’s disease)3 months

Corynebacterium kutscheri 3 monthsMycoplasma spp. 3 monthsPasteurellaceae 3 monthsSalmonella spp. 3 monthsStreptococci

b-haemolytic (not group D)3 months

Streptococcus pneumoniae 3 monthsHelicobacter spp. AnnuallyStreptobacillus moniliformis AnnuallyAdditional organisms tested:

ParasitesEctoparasites: 3 monthsSpecies designationEndoparasites: 3 monthsSpecies designation

Pathological lesions observed 3 months

Data are expressed as number positive/number tested

Positive � ndings in other species in the same unit:

Abbreviations used in this report:

ELISAˆ enzyme linked immunosorbent assay, MICR ˆ microscopy, IFA ˆ immuno� uorescence assay, CULT ˆ culture,PATH ˆ gross pathology, PCR ˆ polymerase chain reaction, HIST ˆ histopathology, NT ˆ not tested




Date of issue:


Species: Rat Strain: (Strain)


Testfrequency

Latesttest date

Latestresults

Testinglaboratory

Testmethod

Historicalresults

( 18 months)

VirusesParvovirusesKilham rat virus 3 monthsRat parvovirus 3 monthsToolan’s H-1 virus 3 monthsPneumonia virus of mice 3 monthsSendai virus 3 monthsSialodacryoadenitis/Rat

coronavirus3 months

Hantaviruses AnnuallyMouse adenovirus type 1 (FL) AnnuallyMouse adenovirus type 2 (K87) AnnuallyReovirus type 3 AnnuallyAdditional organisms tested:

Bacteria, mycoplasma and fungiBordetella bronchiseptica 3 monthsClostridium piliforme


Corynebacterium kutscheri 3 monthsMycoplasma spp. 3 monthsPasteurellaceae 3 monthsSalmonella spp. 3 monthsStreptobacillus moniliformis 3 monthsStreptococci

b-haemolytic (not group D)3 months

Streptococcus pneumoniae 3 monthsHelicobacter spp. AnnuallyAdditional organisms tested:

ParasitesEctoparasites: 3 monthsSpecies designationEndoparasites: 3 monthsSpecies designation





ELISAˆ enzyme linked immunosorbent assay, MICR ˆ microscopy, IFAˆ immuno� uorescence assay, CULT ˆ culture,PATH ˆ gross pathology, PCR ˆ polymerase chain reaction, HIST ˆ histopathology, NT ˆ not tested




Date of issue:


Species: Hamster Strain: (Strain)


Testfrequency

Latesttest date

Latestresults

Testinglaboratory

Testmethod


VirusesLymphocytic choriomeningitis

virus3 months

Sendai virus 3 monthsAdditional organisms tested:

Bacteria, mycoplasma and fungiClostridium piliforme


Pasteurellaceae 3 monthsSalmonella spp. 3 monthsCorynebacterium kutscheri AnnuallyHelicobacter spp. AnnuallyAdditional organisms tested:

ParasitesEctoparasites: 3 monthsSpecies designationEndoparasites: 3 monthsSpecies designationEncephalitozoon cuniculi Annually









Date of issue:


Species: Guineapig Strain: (Strain)


Testfrequency

Latesttest date

Latestresults

Testinglaboratory

Testmethod


VirusesGuineapig adenovirus* 3 monthsSendai virus 3 monthsGuineapig cytomegalovirus AnnuallyAdditional organisms tested:

Bacteria, mycoplasma and fungiBordetella bronchiseptica 3 monthsChlamydia psittaci 3 monthsCorynebacterium kutscheri 3 monthsDermatophytes 3 monthsPasteurellaceae 3 monthsSalmonella spp. 3 monthsStreptobacillus moniliformis 3 monthsStreptococci b-haemolytic

(not group D)3 months

Streptococcus pneumoniae 3 monthsYersinia pseudotuberculosis 3 monthsClostridium piliforme

(Tyzzer’s disease)Annually

Additional organisms tested:

ParasitesEctoparasites: 3 monthsSpecies designationEndoparasites: 3 monthsSpecies designationEncephalitozoon cuniculi 3 months


Data are expressed as number positive/number tested. *Indicate antigen(s) used in serological testing







Date of issue:


Species: Rabbit Strain: (Strain)


Testfrequency

Latesttest date

Latestresults

Testinglaboratory

Testmethod


VirusesRabbit haemorrhagic

disease virus3 months

Rabbit rotavirus 3 monthsAdditional organisms tested:

Bacteria, mycoplasma and fungiBordetella bronchiseptica 3 monthsClostridium piliforme


Dermatophytes 3 monthsPasteurella multocida 3 monthsOther Pasteurellaceae 3 monthsSalmonella spp. 3 monthsAdditional organisms tested:

ParasitesEctoparasites: 3 monthsSpecies designationEndoparasites: 3 monthsSpecies designationEncephalitozoon cuniculi 3 months:





ELISA=enzyme linked immunosorbent assay, MICR=microscopy, IFA=immuno� uorescence assay, CULT=culture,PATH=gross pathology, PCR=polymerase chain reaction, HIST=histopathology, NT=not tested



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