MATERIALS

• Dissecting gloves
• Dissecting pins
• Dissecting trays
• Probe
• Scalpel
• Scissors
• String
• Ruler
  

OBSERVATIONS: PHYSICAL DESCRIPTION OF THE FETAL PIG

Upon removing the pig from the bucket, it comes out very stiff. It was a very pale pink colour with a large slit down its left arm, which was to drain blood from the body. On the head the eyes were closed while the tongue lolled out of the mouth, which appeared to be 'furry' or frayed especially along the edges. Along the neck there were also a few tiny rolls of skin as well as a thicker version of the white hair that covered the body. There are no deformities, all the hooves having the same amount of appendages, that being four toes. In the trunk the umbilical cord was cut open with a total of fourteen nipples on the underbelly of the fetal pig. The measurement of the fetal pig were relatively average compared to the other pigs involved in other experiments going on, it measured from Snout to tail 40 cm and from tip of right foot across chest to tip of left foot 24 cm.
It was discovered upon the first incision that the skin of the pig was very thick and tough requiring pressure to break through. The ribs themselves were covered in layers upon layers of muscle and tissue but at such an early stage of development the bone marrow itself was very soft as well as small, each bone of the rib being approximately 0.8mm wide.

METHOD OF DISSECTION

The first step was to of course gather the materials listed in the post labeled 'Materials'. Once that was done the fetal pig was gotten from the teacher handing them out and put on a dissecting tray. The pig was than rinsed off and string was tied around its leg and under the tray to spread them apart to have a full view of the underbelly. To do this, the legs (in most cases) had to be broken. Once that was done the dissecting began. Putting on gloves, the scalpel was used to begin the incisions indicated in the figure below. Once the incisions were done, the flaps of skin had to be pinned into the wax of the tray to allow for a full view of the fetal pigs anatomy.
The next step was to begin the in depth analysis. Taking a deeper look at specific internal organs of the pig such as the heart, liver excetera. These could be removed from the body and using the scalpel, opened to take a look at their function. Observations of colour, function, fluids, and size were recorded and the organs removed were put into a large beaker for disposal. After observations and pictures had been taken of all necessary body parts the pig could be disposed of. Cleaning up all instruments, and disposing of the body of the fetal pig concludes the dissection process.

DAY ONE OF DISSECTION

On the first day of the dissection process many of the main body parts were discovered and analyzed. These being (in order of finding them):

• Esophagus - Where the food from the mother entered into the fetal pig, that allowed for it to enter into the stomach and be broken down. The food entered through the mother to the umbilical cord and into the fetal pig. It is located in the area of the throat.
• Jugular Vein - The main artery in the body, located in the throat area. All blood circulates through this vein. In the fetal pig it was larger than most other arteries found (as well as a very bright blue for colour indication). In fact when taken out, a lab technician could look directly through it much like a straw.
• Heart - The heart pumps blood through the body. In the pig it was very small, fitting in the palms of a persons hand. When cut open it revealed the main chambers as well as thin slices of veins going through it and the two main arteries for blood entering the heart at the top, and leaving it, located at the bottom of the heart were clearly noticeable. When cut open there was still some blood remaining, it was dark red to the point of almost being brown as well as thicker than most blood seen. The heart was located a few centimeters below the throat and above the liver, right about where the middle point of the underbelly of the pig would be.
• Liver - Helps to break down food, it was located just below the middle of the fetal pigs body. It was fairly large, slightly bigger than the heart and a deep brown colour. When cut through it was a very dense material looking almost like clay. The liver in the pig would be used for food and to help fight off disease.
• Spleen - The spleen was located in the abdomen, it gets rid of old red blood cells as well as recycles iron in the body and is like a blood reserve.
• Stomach - The stomach is where food is broken down through stomach acid, in the fetal pig it was located beneath the liver. It was a squishy, lighter colour, almost a gray and a pink colour. When cut open what looked like bile as well as tiny green balls gushed from the stomach in a creamy off white, liquid.
• Large, Small Intestines - Bound into a roll at the bottom half of the pig they began at the stomach so that the waste from could travel from the stomach to where the intestines end, at the anus. The large intestines was beside instead of wrapped around the small intestines and was a darker colour this being because there was actually waste inside of the large intestine. When removed they were much longer, but in the body were far more scrunched together than in a human body because pigs hunch themselves over more than humans meaning their organs have less space and come together more. That is why the large intestine does not wrap around the small intestines in a pig, as it is more space appropriate.
• Scrotal Sac - Located near the end of the of the body, right by the rectum, between the legs of the pig, were two tiny sacs. They hung in a fashion, with what looked to be a clear liquid inside them. They were certainly the most noticeable for what they were. Shaped much like tears drops they were located before the penis attached to the tubes that became the penis.
• Rectum - At the end of the body, located beneath the tail. It was connected to the large and small intestines and is the space where waste can be divulged from the body.
• Penis - The penis was a tiny flap of skin, barely noticeable lest for the scrotal sacs around it. Looking much like a tube it wound out of the body.

DAY TWO OF DISSECTION

As all important organs had been looked at before, today was the day for general observations:

• There were dozens of tiny veins throughout the body, noticeable only because of their light blue colouring (used as an indicator) even along the ribs.
• The fetal pig though passing away in the womb, had actually developed small teeth in its jaw when pried apart.
• The epidermis of the skin seemed to have several layers being at least one centimeter thick around the entirety of the pig.
• The skin around the legs was the thickest on the whole body.
  
• This particular fetal pig seemed to lack a pancreas.
• It was very difficult to remove the stomach from the body as it seemed to be attached by a web of tissue attached both to the rib cage, the liver and the very skin of the pig.

THE HEAD:

The skull of the pig was cracked open. Compared to a human skull, or a fully grown pig, the skull was very fragile though for being so young and a still born it was still very tough. Cutting away a piece of the skull to take a look at the pigs brain it seemed to look very similar to a humans. It was a dull gray colour as well as very soft and seemed to almost have the wrap around effect yet in fact was a round ball only with molded bumps and curves on it.

OBSERVATIONS / DISCUSSION

Although the first assumption would be that dissecting a piglet would be not only disgusting but incredibly inhumane, that is not how the situation pans out. For one the pig was never alive, but a still born who died in the fetus. For another the experimenter has to put aside all squeamishness to really grasp what a unique chance they are recieving too get an inside look, not only an inside look but to be the one in charge, of a look at the anatomy of a mammal. Not only is it incredibly interesting but it was truly informative to be able to look and open any organs to get a better grasp of exactly how each thing functions.
Though more tools and possibly diagrams could have helped not only for the analysis but for the searching through the fetal pig could have been incredibly helpful, the dissection itself went very smoothly. Which it should since it has been in the Grade Eleven, biology curriculum for many years by now. The only thing that could be changed is the first initial cuts which could be done by someone more experienced. Just because for first timers, and for the squeamish the first cut is not only the hardest emotionally and for the stomach but can cut through important organs as well as how each experimenter cut through it could cause their pigs to look slightly different causing for a multitude of different results.

COMPARISON BETWEEN HUMAN AND FETAL PIG ANATOMY