Tissue Identification
Tissues other than gonad may end up in your sample. A cross section of Eviota susansae, a small (<5cm goby) showing different types of tissue. Bones have been decalcified prior to histology.
Image by E. Schemmel
Handling effects
Parasites
Staining
Several different stains are used for fish histological gonad staging. A good reference to compare and explore staines is the Education Guide: Special Stains and H & E Second Edition. Editors: Kumar, G. L. and J. A. Kiernan eds. This is a guide to stains that is not fish specific.
Below are some examples of the same reproductive phase with different stains.
- Hematoxylin and eosin is one of the most common stains. Hematoxylin stains cell nuclei and DNA a purplish blue and eosin stains cytoplasm and extracellular matrix pink.
Figure 1. Hawaii flagtail, Kuhlia xenura, actively spawning, stained with hematoxylin and eosin. Photo credit: Eva Schemmel.
- Toluidine blue is a thiazine metachromatic dye with high affinity for acidic tissue, staining DNA and cell nuclei darker than other tissues.
Figure 2. Hawaii flagtail, Kuhlia xenura, actively spawning, stained with toluidine blue. Photo credit: Eva Schemmel.
- Schiff’s Mallory Trichrome
Coming soon…