Fish are interesting little creatures.
The first thing you may notice when you hold a fish is that it is slimy. This slime protects the fish from predation, lowers resistance while traveling through water, and also protects the fish from fungi, parasites, and disease.
After you’ve gotten a hold of this slimy little guy or gal, the first step is to cut open its vent. If fish had chins, you would cut all the way up to the chin. It is critical to cut all the way up to the chin; otherwise you would not expose the heart and other organs. Remember not to cut to deep; you might puncture some of the other organs!
Now that we have cut our fish open, we need to determine if it’s a male or female.
Franny the fish should have two eggs sacs. I say Franny should have two egg sacs because depending on her maturity, she may not. If not, eggs will likely come gushing out upon the table-and floor.
Clean up is less than fun.
While Freddy the fish should have two milt sacks. I say should, because I found one fish that had neither eggs nor milt sacks.
When Franny is mature she will deposit her eggs in a particular location. Then Freddy will find Franny’s eggs, and fertilize them.
All of this happens from the vent hole including excreting waste products.
Remember when I said to cut up to the chin?
Here’s Freddy’s heart! In person, it actually looks like a little nose.
Notice this balloon like structure.
This organ is called the swim bladder. Fish can adjust the amount of air within the swim bladder in order to hover at different levels in the water.
These are the kidneys.
Notice that the kidneys look like a little pool of blood. The kidneys are very fragile organs. Even with the tenderest of care, you may end rupturing the kidneys, and then you have a pool of blood in your hands. The joy of clean up!
Next are the eyes.
The key to popping out the eye is putting enough pressure behind the eye socket to tear the flesh to get underneath the eye. The students typically love this part.
The gills are last.
I normally cut the gills out last because they are filled with blood and don’t want my hands to become a bloody mess.
With the time that has normally been allotted to me, I don’t normally have time to crack their melons open and look at the brain. Someday soon; I hope!