Which stain is utilized as a contrast for Ascaris eggs and erythrocytes as well as for bacterial spores?

The utilization of malachite green as a contrast stain for Ascaris eggs, erythrocytes, and bacterial spores is well-established in histopathology. Malachite green is a basic dye that can selectively stain certain cellular components while providing a contrasting background for other structures. It is particularly effective in highlighting the presence of bacterial spores, making them more visible under the microscope. Additionally, this stain's properties allow for clear differentiation between the structures it targets and the surrounding tissues, enhancing the visibility of Ascaris eggs and red blood cells.

The specific staining characteristics of malachite green make it suitable for identifying and contrast-staining these components, as it can highlight the shape and presence of the eggs and spores distinctly against other cellular elements without providing excessive background noise or interference. This selectivity is crucial for accurate diagnostics in histopathology and microbiology.