LHPG 2014 CONGRESS2 - 4 JUNE, SKUKUZA

 

CONTROL OF OJD USING COST-CONTROL OF OJD USING COST-EFFECTIVE, PRACTICAL AND EFFECTIVE, PRACTICAL AND

ACCEPTABLE MEASURESACCEPTABLE MEASURES

Prof Gareth BathConvenor: Small Stock Health Advisory Body (SSHAB)

and Emeritus Professor, Faculty of Veterinary Science

University of Pretoria

BACKGROUNDBACKGROUND

• First SA identification in cattle 1923First SA identification in cattle 1923

• First SA identification in sheep 1967First SA identification in sheep 1967

• Probably imported by Department of AgricultureProbably imported by Department of Agriculture

• Escaped from Animal Institutes in 1980sEscaped from Animal Institutes in 1980s

• Became a problem in Western Cape commercial Became a problem in Western Cape commercial flocks 1990sflocks 1990s

• First survey doneFirst survey done

• Current regulations promulgatedCurrent regulations promulgated

• Vaccination of positive flocks allowed in about 2003Vaccination of positive flocks allowed in about 2003

• Small Stock Health Advisory Body 2005Small Stock Health Advisory Body 2005

Small Stock Health Advisory Small Stock Health Advisory Body (SSHAB) 2005Body (SSHAB) 2005

PARTICIPANTS

National Wool Growers’ Association (NWGA) 2

National Emerging Red Meat Producers’ Organisation (NERPO) 2

Red Meat Producers’ Organisation (RPO) 2

Livestock Health and Production Group (LHPG) 2

SA Federation Stud Breeders’ Society (SAFSBS) 2

SA Stud Book (SASB) 1

SA Federation of Livestock Auctioneers (SAFLA) 2

Convener 1

PRINCIPLES FOR ACCEPTABLE PRINCIPLES FOR ACCEPTABLE OJD CONTROL MEASURESOJD CONTROL MEASURES

• Protect interest of infected flocksProtect interest of infected flocks

• Protect interest of uninfected flocksProtect interest of uninfected flocks

• Practical, affordable measuresPractical, affordable measures

THE NEED FOR CHANGETHE NEED FOR CHANGE

• Current regulations unworkableCurrent regulations unworkable

• Unintended consequences (dishonesty)Unintended consequences (dishonesty)

• No or little monitoring of salesNo or little monitoring of sales

• Allegations of vaccine dispersalAllegations of vaccine dispersal

• No other country has had successNo other country has had success

• Major countries (and OIE) do not regulate Major countries (and OIE) do not regulate

• Zoning indefensible without surveysZoning indefensible without surveys

• State has not acted with vigour on OJDState has not acted with vigour on OJD

ORIGINAL PROPOSALS FROM ORIGINAL PROPOSALS FROM SSHAB TO DAFF (2008)SSHAB TO DAFF (2008)

• Extensive consultation over 3 yearsExtensive consultation over 3 years

• Proposals based on consensusProposals based on consensus

• Tried to have a system based on zoningTried to have a system based on zoning

• Needed whole-hearted support from DAFF & Needed whole-hearted support from DAFF & ProvincesProvinces

• No action for over 2 yearsNo action for over 2 years

• Problems of management changes at DAFFProblems of management changes at DAFF

• Decided to draw up workable systemDecided to draw up workable system

• The nature of the disease point to industry-based The nature of the disease point to industry-based control measurescontrol measures

1.1. Targeted Detection SurveysTargeted Detection Surveys

2.2. OJD Control AreasOJD Control Areas

3.3. Other areas of South AfricaOther areas of South Africa

4.4. Detection and TestingDetection and Testing

5.5. Liaison and ReviewLiaison and Review

SUMMARY OF OJD CONTROL SUMMARY OF OJD CONTROL PROPOSALS: July 2008PROPOSALS: July 2008

CURRENT PROPOSALS FROM CURRENT PROPOSALS FROM SSHAB TO DAFF (2010)SSHAB TO DAFF (2010)

• Abandon zoning as unworkableAbandon zoning as unworkable• End quarantine of positive farmsEnd quarantine of positive farms• Change status from controlled to notifiableChange status from controlled to notifiable• Separate Ovine from other forms of JDSeparate Ovine from other forms of JD• Notification of outbreaksNotification of outbreaks• Vaccine supply simplified but still subject to Vaccine supply simplified but still subject to

veterinary prescriptionveterinary prescription• Information of vaccines, sales must be recordedInformation of vaccines, sales must be recorded• Sales of live sheep must only be done with a Sales of live sheep must only be done with a

Vendor DeclarationVendor Declaration• Draft of proposed Regulations suppliedDraft of proposed Regulations supplied• Moratorium requestedMoratorium requested

OJD VACCINE PURCHASE OJD VACCINE PURCHASE DECLARATIONDECLARATION

• CompetenceCompetence

• Flock regarded as OJD PositiveFlock regarded as OJD Positive

• Doses commensurate with flock sizeDoses commensurate with flock size

• Permanent unique ear tagsPermanent unique ear tags

• No removal of vaccine reactionNo removal of vaccine reaction

• Use only on own sheepUse only on own sheep

• Vendor Declaration with salesVendor Declaration with sales

• Sales to be recordedSales to be recorded

CALCULATE COST/BENEFIT CALCULATE COST/BENEFIT OF VACCINATIONOF VACCINATION

Consider annual deaths firstConsider annual deaths first

current cost of vaccine/sheepcurrent cost of vaccine/sheep_________________________ X 100 = percentage of annual deaths to justify vaccination_________________________ X 100 = percentage of annual deaths to justify vaccination

current price of breeding ewecurrent price of breeding ewe

  Examples:Examples:  R15__R15__ X 100 X 100 = 1 % annual mortality= 1 % annual mortalityR1500R1500    R30__R30__ X 100 X 100 = 2 % annual mortality= 2 % annual mortalityR1500R1500  R30_R30_ X 100 X 100 = 4 % annual mortality= 4 % annual mortalityR750R750  R20__R20__ X 100 X 100 = 0.5 % annual mortality= 0.5 % annual mortalityR4000R4000

ADD OTHER COSTS & ADD OTHER COSTS & CONSIDERATIONSCONSIDERATIONS

• Cost of raising extra replacementsCost of raising extra replacements

• Cost of early deaths, less lambings per eweCost of early deaths, less lambings per ewe

• Effects on flock structureEffects on flock structure

• May lose 8 – 10, even 15% adults annuallyMay lose 8 – 10, even 15% adults annually

OTHER RISK FACTORSOTHER RISK FACTORS

• buying policy (unvaccinated sheep)buying policy (unvaccinated sheep)

• sheep (especially lambs) concentrations on sheep (especially lambs) concentrations on grazinggrazing

• moisture – retaining pasturesmoisture – retaining pastures

• type and timing of raintype and timing of rain

• use and timing of irrigationuse and timing of irrigation

• ambient humidity at lambingambient humidity at lambing

• temperature rangetemperature range

• feeding system (on ground or raised)feeding system (on ground or raised)

• water troughswater troughs

OJD VACCINEOJD VACCINE

• Gudair (Virbac)Gudair (Virbac)

• Killed oil adjuvantKilled oil adjuvant

• Lowers losses by 90%Lowers losses by 90%

• Lowers carriers by 90%Lowers carriers by 90%

• Lowers shedding by 90%Lowers shedding by 90%

• Authority & prescription - SVAuthority & prescription - SV

OJD VACCINE (cont):OJD VACCINE (cont):

• Only for infected flocksOnly for infected flocks

• Single injection in lambsSingle injection in lambs

• Permanent identificationPermanent identification

• Subcutaneous in neckSubcutaneous in neck

• Severe reactions possibleSevere reactions possible

VETERINARY GUIDANCE FOR VETERINARY GUIDANCE FOR PRESUMED OJD-NEGATIVE FLOCKSPRESUMED OJD-NEGATIVE FLOCKS

• Owners must be OJD-awareOwners must be OJD-aware

• Never buy sheep without prior adviceNever buy sheep without prior advice

• Never buy sheep from speculatorsNever buy sheep from speculators

• Always demand a Vendor DeclarationAlways demand a Vendor Declaration

• Ensure that the implications of each point in the Ensure that the implications of each point in the

Vendor Declaration is well understoodVendor Declaration is well understood

• If in doubt, then rather do not buyIf in doubt, then rather do not buy

• It only takes one apparently healthy carrier sheepIt only takes one apparently healthy carrier sheep

• The signs of OJD may take 5-10 years to become The signs of OJD may take 5-10 years to become

apparentapparent

• The property becomes permanently OJD positiveThe property becomes permanently OJD positive

• Never accept any verbal assurance on OJD statusNever accept any verbal assurance on OJD status

• Explain to breeders that testing for OJD will be to Explain to breeders that testing for OJD will be to

their benefit - the lowest of risk categoriestheir benefit - the lowest of risk categories

• Emphasize that there is no such thing as “no risk”Emphasize that there is no such thing as “no risk”

DRAFT VENDOR DECLARATIONDRAFT VENDOR DECLARATION1. I hereby declare that I am the owner or authorised representative of the sheep on sale and

am competent to make this declaration

2. The sheep for sale are clearly identified in the accompanying description. YES NO

3. The sheep for sale were born on my farm. YES NO

4. The farm has a closed flock policy. YES NO

5. know the signs of the disease and to the best of my knowledge, all of my properties are free of cases of Ovine Johne’s Disease

YES NO

6. I have actively looked for Ovine Johne’s Disease and have had tests done for this.

YES NO

7. To the best of my knowledge, my immediate neighbours and farms in my magisterial district of my farm(s) are free of cases of Ovine Johne’e Disease.

YES NO

8. The sheep on my properties have been vaccinated against Ovine Johne’s Disease and are appropriately identified as such.

YES NO

9. If vaccinated, the number of years that the vaccinations have been done is    years

NOTE: Vaccination does not mean freedom from OJD, vaccinated animals can still be carriers.NOTE: Vaccination does not mean freedom from OJD, vaccinated animals can still be carriers.Buyers should consult their veterinary advisor before any purchasesBuyers should consult their veterinary advisor before any purchases

Signature: _______________________________Signature: _______________________________ Date: _______________________________Date: _______________________________

Farm:____________________________________Farm:____________________________________ District: _____________________________ District: _____________________________

Owner or Authorized representative:________________________________________________________________________Owner or Authorized representative:________________________________________________________________________

YesYes NoNo

YesYes NoNo

YesYes NoNo

YesYes NoNo

YesYes NoNo

YesYes NoNo

YesYes NoNo

yearsyears

CURRENT (2014) COST OF OJD CURRENT (2014) COST OF OJD PFS TESTPFS TEST

• About R500 / poolAbout R500 / pool

• With 7 pools, about R3 500 / farmWith 7 pools, about R3 500 / farm

• Target older, thinner sheepTarget older, thinner sheep

• Cost of transport, sampling etc? R2 500Cost of transport, sampling etc? R2 500

• Maybe around R6 000 / farmMaybe around R6 000 / farm

• This is the price of one good ramThis is the price of one good ram

• Divide farm cost by number of rams soldDivide farm cost by number of rams sold

• If 100 rams, cost / ram = R60If 100 rams, cost / ram = R60

CAN WE “ERADICATE” OJD CAN WE “ERADICATE” OJD FROM A FARM?FROM A FARM?

• Yes, depopulate for 18 – 24 monthsYes, depopulate for 18 – 24 months

• This is not a practical optionThis is not a practical option

• Reinfection remains a problemReinfection remains a problem

• May be possible (South Australia)May be possible (South Australia)

• Vaccinate for 5 years (lower infection on farm)Vaccinate for 5 years (lower infection on farm)

• Test and cull (like bovine TB)Test and cull (like bovine TB)

• May be able to classify farms by risk categoryMay be able to classify farms by risk category

CURRENT SITUATION (May 2014)CURRENT SITUATION (May 2014)

• OJD positive flocks may trade live sheepOJD positive flocks may trade live sheep

• SSHAB meetings via NAHF with DAFFSSHAB meetings via NAHF with DAFF

• Vendor declaration gathering supportVendor declaration gathering support

• Pooled Faecal Sample test to detect OJD in Pooled Faecal Sample test to detect OJD in flocks under testingflocks under testing

• Targeted Detection Surveys in breeder flocks Targeted Detection Surveys in breeder flocks and communal areas have supportand communal areas have support

• Vaccine sales have plummeted!Vaccine sales have plummeted!

• Support from industry and veterinarians is Support from industry and veterinarians is essentialessential

ENDEND

• Western Cape Province Western Cape Province

– Known OJD area Known OJD area

• Western Cape ProvinceWestern Cape Province

– Other areasOther areas

• Other ProvincesOther Provinces

– High risk areasHigh risk areas

– Sellers of breeding stockSellers of breeding stock

– Known diagnosesKnown diagnoses

– Goats (& wildlife?)Goats (& wildlife?)

1. TARGETED DETECTION SURVEYS1. TARGETED DETECTION SURVEYS

• Identify and declare areasIdentify and declare areas

• All farms includedAll farms included

• Exemptions possibleExemptions possible

• Free trade within areaFree trade within area

• Movement records to be keptMovement records to be kept

• Free importation of sheepFree importation of sheep

• Written vendor declarationsWritten vendor declarations

2. OJD CONTROL AREAS2. OJD CONTROL AREAS

• Vaccination strongly recommendedVaccination strongly recommended

• Clear, unique, permanent tagsClear, unique, permanent tags

• Advise purchase of vaccinated sheepAdvise purchase of vaccinated sheep

• Vaccinate (if not done before)Vaccinate (if not done before)

• Live sheep can be sold directly for slaughterLive sheep can be sold directly for slaughter

• Embryos, semen & OJD-free sheep: strict Embryos, semen & OJD-free sheep: strict

safeguardssafeguards

• Breeders must take responsibilityBreeders must take responsibility

OJD CONTROL AREAS (continued)OJD CONTROL AREAS (continued)

• Vendor Declaration: risk factorsVendor Declaration: risk factors

• Detection surveys neededDetection surveys needed

• Encourage breeders to testEncourage breeders to test

• Good management practicesGood management practices

• No vaccination allowedNo vaccination allowed

• No purchase from control areasNo purchase from control areas

• OJD awareness promotedOJD awareness promoted

3. OTHER AREAS (OJD “FREE”)3. OTHER AREAS (OJD “FREE”)

• Standard proceduresStandard procedures

• Authorised laboratoriesAuthorised laboratories

• Multiple tests Multiple tests –– confirmation confirmation

• Histological, bacteriological and PCRHistological, bacteriological and PCR

• Flock, not individual testsFlock, not individual tests

• Logistics and budgeting crucialLogistics and budgeting crucial

4. DETECTION AND TESTING4. DETECTION AND TESTING

• State to pay for surveys State to pay for surveys

• Subsidisation recommendedSubsidisation recommended

• Protocols requiredProtocols required

• Abattoir monitoring and tracebackAbattoir monitoring and traceback

• Research neededResearch needed

DETECTION AND TESTING (continued)DETECTION AND TESTING (continued)

• Strong liaison essentialStrong liaison essential

• All parties includedAll parties included

• Positive attitude neededPositive attitude needed

• Everything open to reviewEverything open to review

• 3 Principles to be used3 Principles to be used

• Helpline required for adviceHelpline required for advice

• Suitable supervisor requiredSuitable supervisor required

5. LIAISON AND REVIEW5. LIAISON AND REVIEW