Using Charm II 7600 For ResidueTesting in Meats in Barbados

Dr Trevor King/ June Roach, Vet Services Lab (VSL)Ministry of Agriculture & Rural Development, Barbados

VETER INARYSERVICES

LABORATORY

Poultry In dustry(includ ing Hatcheries)

PrivateVeterinarians

In ternational Agencies(IICA, CARDI, F AO)

Livestock Farmers& Exporters

Pet Owners

Ab attoir &Meat In spectors

Me at Processors& Exporters

Meat Importers Min is try of Health(PHIs)

MAR(Other Sections)

The Police

Racehorse OwnersB’dos WildlifeReserve

V eterin aryField Services

The Pin eHill Dairy

VSL’s Client Base

Sample Submission - MeatLean Muscle TissueFat freeNo highly processed meatMinimum of 12 grams per group of testsClearly labelled ziplock bagKeep samples cool or frozenSubmit samples earlyInformation required

Sample Submission - Milk

Minimum of 40 mls per group of testsClearly labelled, clean containerKeep samples cool or frozenSubmit samples earlyInformation required

Charm II 7600 Testing System

“The only comprehensive testing systems in usein FDA laboratories and government testinglaboratories worldwide”

FDA approved tests for milkAOAC-RI approved tests for milk

The Charm TestIs a microbial (or antibody) receptor assayUses exempt quantities (very small amounts) of a

radioactive tracerSpecific “binder” tablet used for each family of

antibioticsSample with specific antibiotic binds to receptor

– e.g. In a sample containing Tetracycline and Gentamycin,only Tetracycline will bind to the Tetracycline receptor

If sample contains little or no antibiotic, then labeledspecific tracer will bind to “binder”

Principle of the Charm Test

Samplemay contain antibiotic

BinderTracer

labelled antibiotic

NEGATIVE REACTION POSITIVE REACTION

More labelled antibiotic boundCount is highSample is NEGATIVE

Little or No labelled antibioticboundCount is lowSample is POSITIVE

Antibiotic

Test Method

• Usually single test done per sample perantibiotic

• Performance monitoring is done before actualsamples are tested

• Software “flags” suspect samples andrequests a retest

• Suspect samples are retested with positive andnegative controls

Antibiotics commonly used to treatanimals

Beta-lactams e.g. Penicillin

Aminoglycosides: Gentamycin & StreptomycinSulfonamides or Sulfa drugs e.g. Sulfamethoxazole

Tetracyclines e.g. Oxytetracycline

One Meat sample generates 5 tests

Beta-lactams Gentamycin Streptomycin Sulfa Drugs Tetracyclines

Antibiotics commonly found in Milk

Beta-lactams & CephalosporinsCloxacillinGentamycinNeomycinStreptomycinTetracyclines

One milk sample generates 6 tests

Beta-lactamsGentamycin/Neomycin

Gentamycin/Streptomycin

Sulfa Drugs

TetracyclinesCloxacillin

Charm Sciences ROSA Test

Rapid One Step AssayENROFLOX Test - a quick test for Enrofloxacin

detection at MRL (Maximum Residue Limit) inchicken muscle tissue.

Sensitivity and Selectivity—ConcentrationResponse for Enrofloxacin in Tissue

Drug MRL ppb (partsper billion)

Tissue Concentrationppb

Percent Positive

Enrofloxacin 30 30 100%

0 0%

ROSA Principle - Lateral Flow

300ul of sample extract is added to the sample well.

The extract is absorbed by the orange sponge and transferred tothe porous paper.

As the test is incubated the extract travels up the paper andpicks up the purple indicator beads which are located just abovethe orange sponge.

These beads are going to bind either to the test line (willdevelop next to the T) or the control line (located further up thestrip next to the C) .

Results

If sample containsEnrofloxacin abovethe safe levels theseantibiotics bind to theindicator beads andthe beads slide pastthe test line. Thisresults in a lighter testline than control linefor positive samples.

If the sample does notcontain Enrofloxacinabove the safe levelsthen the beads can bindto the test line resultingin a darker test linethan control line fornegative samples.

Total Number of Tests and PositivesNovember 1996 - March 31st 2002

3451

150

0

1000

2000

3000

4000

Total Positives

Total Number of TestsNovember 1996 - March 31st 2002

By sample type

1996 -1997 1997-1998 1998-1999 1999-2000 2000-2001 2001-2002 TOTALMilk 0 235 602 524 444 492 2297Chicken 8 2 12 283 202 331 838Turkey 0 0 5 20 25 50Pork 10 0 12 45 18 0 85Beef 4 6 4 0 0 0 14Mutton 0 0 0 10 0 0 10Eggs 0 0 0 50 3 104 157

TOTAL 22 243 630 917 687 952 3451

Total Number of PositivesNovember 1996 - March 31st 2002

By sample type

1996 -1997 1997-1998 1998-1999 1999-2000 2000-2001 2001-2002 TOTALMilk 0 15 33 40 18 5 111Chicken 1 0 1 5 3 6 16Turkey 0 0 0 0 1 1 2Pork 2 0 1 4 3 0 10Beef 4 0 1 0 0 0 5Mutton 0 0 0 0 0 0 0Eggs 0 0 0 0 0 6 6

TOTAL 7 15 36 49 25 18 150

Number of PositivesNovember 1996 - March 31st 2002

By Antibiotic type

30

33

2869

44

Beta-lactamsCloxacillinGentamycin/Neomycin*Gentamycin/Streptomycin*SulphonamidesTetracyclines

TOTAL: 150

Total Number of Tests and Positivesfor Milk April 1st 1997 - March 31st 2002

23515

602

33

524

40

444

18

492

5

2297

111

0

500

1000

1500

2000

2500

97-98 98-99 99-00 2000-01

2001-2002

totalTests

Positives

Numberof Tests

Year

Total Number of Tests and Positivesfor Chicken April 1st 1997 - March 31st

2002

8 1 2 12 1

283

5

202

3

331

6

838

10

0200400600800

100096

-97

97-9

8

98-9

9

99-0

0

2000

-200

1

2001

-200

2

tota

l

50

3

104

6

157

6

020406080

100120140160

1999-2000 2000-2001 2001-2002 Total

Total Number of Tests and Positivesfor Eggs April 1st 1999 - March 31st 2002