Dissection reflection

[silverflight8]

I feel too tired to actually write something, so here is my little...essay...on the fetal pig dissection I did a few days ago.

WARNING: possibly quite squicky, so don't read if you don't want to hear about dissections and graphic descriptions of the same. I believe the pigs are not killed deliberately for this; the mothers are killed for their meat and the fetus is usually found inside.

 

I admit, I’m always a little uneasy about dissections—particularly when they happen to include organs that are present outside the body. Eyeballs, for instance. It’s hard not to think that that—thing?—is dead; like cooked fish, the eyes follow you everywhere. Moreover, the reality of what science is—messy, irregular, a little imperfect empirical evidence smoothed into clearer theory—becomes apparent in dissections.   

            So the fetal pig. My first thought was that it was bigger than I’d expected, and the second was that it had hair. The face was furry. As a person who thinks furry things are cute (with, of course, the exception of tarantulas and the like) I thought: “Oh no.” The pig looked ready to be born, and if it weren’t for the smell of formaldehyde and the unnatural collapsed position, you could have been fooled into thinking it was still alive.

            I sliced the pig open from umbilical cord to neck, and I was unpleasantly presented with oozing, whitish fluid that we guessed was whatever preservative was used. We cut and pulled the skin and muscle off, bending the ribs apart as we went, to open up the chest cavity. The heart was very, very small, and the lungs around it were only spongy tissue. Since the pig hadn’t been born, and thus had no reason to use its lungs, I assumed that was the explanation and watched Annie cut it open.

            When I cut into the lower section of the pig, it began to gush fluid. As usual, my friends found a way to make it slightly more disgusting, commenting that “It looks just like V-8 juice,” thereby putting me off that beverage for a few years. The observation was true, though: the fluid was reddish, a little speckled, somewhat watery, and simply gushing out of the pig. After a few minutes of indecision, we went to squeeze the fluid out of the pig. (I also must confess that at this point, I busied myself emptying the tray—I felt completely unable to reach over and use my hand to actually squish the pig’s midsection.)

Sally had somehow teased the bladder out of the pig while we were still trying to cut through the ribcage (which was still cartilage), and we paused in the cutting to discuss what it was. It looked like an elongated piece of the large intestine, rather than the round sphere-shaped sac I’d envisioned. We decided at length that it was a bladder, and then cut open the stomach.

            The liver was much larger than I’d imagined, even though the diagrams had shown it to be larger than the stomach. We cut the liver away from the body, damaging the thin membrane of the diaphragm as we did so, and cut that open, too. Under the liver was a yellow-green tinged something—we guessed it was whatever was in the large intestine that we’d inadvertently cut open. The spleen, a little slip of purple tissue, was connected to the stomach—it was just like ordinary tissue when it was cut open, with no specific structures inside.

            I unearthed the left kidney, and Lucy said under her breath that she understood why it had been named after the bean—the colour was the same, although the right kidney was blackish and looked bruised. The fetal pig kidney was smaller than the one I’d dissected earlier this year, but the renal pyramids and the medulla and cortex division was still clear. The ureter was visible as a white line buried under tissue.

            The intestines resembled the brain with its little crevices and complicated tangles. It did not disentangle itself into a long string as I hoped it would; either the intestines had not yet destroyed the tissue connecting some of the intestines to others, or else the Body Worlds exhibit had been snipped to open up properly. The pig’s intestines were just a jumble of slightly rubbery tissue, kinked and tangled, but the large intestine and small intestine were still distinct. We removed it, too.

            In poking around the hind sections of the pig, Annie and Lucy found things that we assumed to be the ovaries—very small, and had been damaged by cutting away the surrounding tissue.

            The preservative must have also congealed the blood a little differently. Instead of the usual brown colour of dried blood, the veins and arteries that we cut open were solid with disconcertingly bright red blood. It was almost as though someone had solidified the blood and left it there—it was possible to strip the vein walls away from the actual blood.

            By the next day, we’d emptied the pig a few times, so the skin was stretched and looked shrivelled where it had been peeled back. We turned the pig over to slit open the skin along the spine and peeling the flesh back. The space between the back and the chest cavities is very small, I discovered, as I accidentally poked through the space between the ribs.

            After decapitation, Lucy sliced the top of the skull, laying the skin and flesh open and exposing the skull; we took pictures and she began to saw through the bone. I’m still not quite sure how she and Annie managed to split open the skull, but they did—the brain was removed from the skull when I looked up again. The eyeball was cut open, squirting a little, and the vitreous humour mostly came out when the eyeball was cut through. The eye muscles are quite strong; Sally and Lucy and Annie all struggled to gouge out the eyes.

            The neck of the pig was a mess of tissue and bone. There was some debate over which was the spine and which was the nerve endings. In humans, I realized, this would be quite important, since the head is heavy and it would be quite detrimental to have the neck collapse under the weight.