Gamma-Check-B

Manufacturer: Plasvacc

Gamma-Check-B Indications

The product is used for the semiquantitative detection of bovine gammaglobulin levels in blood and serum.

Test Principle

The test is based on the principal that glutaraldehyde reacts with certain blood proteins (gammaglobulin and fibrinogen) to form a solid gel. The time taken for the gel to form is inversely proportional to the concentration of these proteins. There have been reports on the application of this reaction as a means of detecting gammaglobulin levels in foals, calves, puppies and nondomestic neonatal ruminants.^1-7 Many of these papers have reported excellent results when using serum. The GAMMA-CHECK-B™ test is available as a means of semi-quantitatively measuring IgG in whole blood or serum.

Through new production methods, the glutaraldehyde used in the test is available in a pure, stable form. This allows a long shelf life and avoids some of the pitfalls found by earlier researchers.⁸ Because glutaraldehyde is potentially toxic, it has been sealed into a tube so that operator exposure does not occur.

Test Procedure

When to Test: GAMMA-CHECK-B™ can be used to screen calves at any age for gammaglobulin levels.

Recent research has shown that most neonates that ingest good quality colostrum will have a high (>800 mg/dl) IgG level by eight (8) hours of age.^9,10 Using the test at eight (8) hours still allows the oral route to be used for additional supplementation of colostrum or plasma (absorption can occur via this route for up to 24 hours).¹¹

When used on calves of more than 24 hours of age, supplementation of IgG, if required, must occur parenterally.

a. Whole Blood:

1. The GAMMA-CHECK tube should be filled to the red line on the label with whole blood. The vacuum in the tube is sufficient to fill the tube to this line. The filling can be done either directly from the vein, as in the routine collection of blood samples, or by introducing previously drawn blood (with EDTA - lavender top - anticoagulant) into the tube. The reason for the latter alternative is because when the blood is mixed with the stabilized glut, the reaction time must begin. The practitioner may not be in a position to do that when drawing the blood straight from the animal - it may be inconvenient.

2. As soon as the whole blood enters the GAMMA-CHECK tube, the time must be noted. The end point is the formation of a firm clot/gel. Every minute or so, the tube should be gently tilted to approximately 45 degrees. Tilting too far may obscure the contents of the tube because the thickening blood sticks to the side. Blood will no longer run along the sides of the tube when the end-point is reached. Note the time taken when this occurs and calculate the length of time to form the solid gel.

If a solid clot forms in less than five (5) minutes, the IgG level is above 800 mg/dl.

A solid clot formation in less than three (3) minutes indicates a level of >1,500 mg/dl.

Occasionally a soft jelly-like clot will form. In the majority of such cases, this can be interpreted as a firm clot. However, the test should be repeated with another sample or using a different type of test.

b. Serum:

1. Whole blood is first collected into a plain 5 mL or larger red-top tube. When clotting and clot retraction is complete (approximately 1 to 2 hours), the tube should be centrifuged.

2. Using a hypodermic syringe and needle, 1.5 mL of the serum is removed from the collection tube and inserted into the GAMMA-CHECK-B™ tube. The time is noted and the contents are observed by occasionally tilting the tube until a solid gel forms. The time taken for this to occur is noted.

Solid clot formation in less than five (5) minutes indicates an IgG level of >500 mg/dl.

Precaution(s)

The kit should be kept in the refrigerator at 4°C.

Gamma-Check-B Caution(s)

Using the test with whole blood in calves that may be septic (with elevated fibrinogen levels), dehydrated or hemolyzed may give a false-positive result. If any of these conditions are present, the test should be repeated with serum (see Test Procedure) or another type of test.

Glutaraldehyde is caustic to the skin and eyes. If a tube breaks and skin or eye contact occurs, wash with copious quantities of cold water and consult a physician.

References

Available upon request.

Presentation

10 and 25 tests per kit.

Nac No.

11280033