For animal health diagnostic purposes or for specific anatomic or cellular components, Special Stains are performed. PHL performs a wide variety of special stains to assist in diagnostics. A chemical dye (other than the routine hematoxylin and eosin – H&E) is applied to tissue sections to demonstrate specific anatomical or cellular components.

Some of the routine special stains performed are:

• Periodic Acid-Schiff reaction (PAS): demonstrates the presence of glycogen
• Brown and Hopps Gram stain (B+H): demonstrates the presence of Gram positive and Gram negative organisms
• Steiner stain: demonstrates the presence of spirochetes
• Grocott Methenamine Silver (GMS): demonstrates the presence of fungi.