VMC 311: Systematic Veterinary Bacteriology and Mycology (2+1)

PLATE AGGLUTINATION TEST/ROSE BENGAL PLATE TEST (RBPT)

• It is modification of the tube agglutination test. The antigen consists of a suspension of Brucella organisms stained with Rose Bengal and adjusted to pH 3.6.
• The test is carried out by adding 0.3 ml of serum to 0.3 ml of stained antigen on a plate or tile, mixing and examining for agglutination after 4 minutes.

Materials

• Brucella abortus coloured antigen
• Test and Positive serum
• Glass plate
• NSS/PBS
• A spreader – Tooth picks are ideal spreaders

Procedure

• Take one drop each of test serum, positive serum and NSS and place them separately far apart on the glass slide.
• Add one drop of coloured antigen to each drop.
• Mix it over an area of 2cm in d.m. by using separate spreaders.
• Wait for two minutes and look for agglutination reaction
• In positive case clumping of antigens is observed, while no reaction is observed in drop containing NSS (Negative control).

Uses

• It is a simple and rapid test that can be easily carried out in field.
• This test has now been devised for rapid diagnosis of bacterial diseases such as salmonellosis, pasteurellosis etc.
• Blood group typing is also done by this method.
• By making further dilution of test sample, serum titration can also be done.