Pacific Sturgeon Spleen

discomorphella · Post by **discomorphella** » Thu Sep 06, 2007 12:18 am

This is my second sectioning attempt using a new (for me) embedding medium, polyester wax. Its much easier to use than paraffin, albeit more expensive. It doesn't require clearing solvents like xylene, the tissue is simply fixed, then dehydrated in ethanol or isopropyl alcohol and embedded. This sample came from a sturgeon I caught, and saved bits of its internal organs when it was cleaned (yes, this did raise eyebrows among the other fishermen...).

Sample info:
Acipenser transmontanus (Pacific Sturgeon) spleen, collected ~30 mins postmortem (took a bit to get to shore to clean the fish), fixed in buffered formalin, dehydrated in isopropanol, embedded in polyester wax, and sectioned at 5 um using an 820 microtome (a 1935 model I fixed up). Sections were taken up on gelatin coated slides, and stained using Ehrlich's hematoxylin (blue, nuclei) and phloxine B (red, granules and cytosol, especially in the erythrocytes and granulocytes).
You can see the nucleated erythrocytes, granulocytes (with red-staining round granules, there's a nice one at lower center in the lumen of the blood vessel) and numerous other cell types in the red and white pulp of the spleen.
Optics are not my usual orthoplan, this shot was from a BX-51 with a UPlanFl 100X / 1.3 NA objective and a 3.3 MPxl camera.
Next time you catch a fish think about what interesting things are inside of it....I will post more pics of the spleen, as well as more of the tissues as I get them processed.

--David

James Sutherland · Post by **James Sutherland** » Mon Sep 10, 2007 2:14 pm

David, thanks for the information & interesting photos. I'll have this on file should I ever get into this type of slide preperation.
On the Kona coast of the Big Island we were always concerned with ciguatera. Many fish would accumulate toxins in high concentrations via the food-chains. Especially the reef fish it seemed...after listening to the bad sickness experience of some I didn't do so much spear fishing & tried a little u/w photography.
Aloha, Jim

Planapo · Post by **Planapo** » Tue Sep 11, 2007 7:22 am

Excellent histological photograph accompanied by very interesting information. Thanks for sharing, David!

I wonder if you catch Acipenser with rod, line and hook as a leisure fisherman over there, or if they are caught commercially by boat and net.
Over here our Acipenser sturio has died out, but now there are efforts to reintroduce this species to the wild from farmed stock.

Cheers,
Betty

edit: Typo

discomorphella · Post by **discomorphella** » Tue Sep 11, 2007 9:23 am

Hi Betty--

We caught this one with hook and line. You are allowed to keep only a certain size range (approximately 114 cm to 150 cm) to ensure that you don't remove fish old enough to reproduce, and the fishing season is limited both in time and number of fish caught to help support the population. The fish this slide came from was approximately 128 cm long. The other fishermen were amused to see me sorting through the viscera with a #10 scalpel and bottles of formalin. I started on the spleen first since I wanted to have a good test of my hematoxylin (you have to let it "ripen" or oxidize for a long time before its ready to stain). I have embedded an assortment of different tissues, and have started sectioning them. I'll post more shots as I try different stains or find interesting structures.
Thanks,

--David