Fetal Pig Lab Report
Exploration of the Anatomy of a Fetal Pig and Its Organs Through Dissection
Written by Jason Camacho
Contributors:
Anthony Camiccia
Ivy Topzands
Aleksandra Ivanova
J.Immel, Ph.D.
Introduction
Many scientists are experts when it comes to the placement of the organs in the human and animal body. Scientists can point anywhere and name the organ closest to it, but how do the scientists know exactly where each organ is? How do the scientists know the number of organs that are in your body? How do they know all this? Well, scientists know all about the anatomy of humans and animals because of a procedure called dissection. Dissection is when people cut open and analyze the structures and relations inside. In this situation a fetal pig …show more content…
was cut open and analyzed1. Dissection has been around as early as the third century B.C. The dissections were being carried out by the Greek physicians Herophilus of Chalcedon and Erasistratus of Chios. During these times, it was against Roman law to dissect a human a body, so many physicians, including Galen, were forced to work with only animals. Because of this, many physicians dissected various types of animals, assuming they had the same anatomy as the human. Eventually, the laws changed and human dissection was now legal. With human dissection being legal, many physicians performed human dissections and discovered many new things about the human anatomy1. A man called Andreas Vesalius was an important figure in the history of dissection.
This man is known as the founder of the human anatomy. Vesalius was born on December 31, 1554 in Brussels, Belgium and died on October 15, 1564 in Zakynthos, Venetian Ionian Islands, Greece. Vesalius was a physician who changed biology and practice of medicine by clearly and carefully describing the human anatomy. He wrote his own anatomy textbook using his own observations he took when dissecting humans. Vesalius was from a family of physicians and pharmacists. He decided to follow the family tradition and went to medical school. In 1537, he got his M.D. degree and became a lecturer in surgery. He was responsible to giving anatomical demonstrations. For the first few years he followed Galen’s methods and theories, but eventually he decided to use his own method. By using his own method, he discovered that Galenic anatomy had not been based off the dissection of the human body. Gale came up with the human anatomy by conclusions based from dissections made on varies types of animals. Vesalius also accurately described the muscles in the human body. He described where the muscles were located and what their job was. Vesalius was a man who discovered so much about human anatomy that he became a figure in the history of …show more content…
dissection2. Materials and Methods
Materials
One fetal pig One waxed aluminum container Two pieces of string One scalpel One pair of scissors One straight probe One bent probe One pair of forceps One eyedropper Plastic ruler
Method
First, the pig was received and carefully placed on the aluminum container. The pig was placed down, so that the ventral side was facing up. The limbs were then abducted and tied with string to the pan. Once the pig was tightly secured to the pan, the pig was measured. The external features of the pig were analyzed and cataloged. An incision was made using the scalpel. It was made on the superior sternum on the ventral surface. Scissors were then used to cut in the proximal and distal direction at the same duration. Scissors were then used to cut around the left side of the umbilical cord. We continued cutting inferior of the umbilical cord. The same process was repeated, except used a scalpel to cut deeper and depart the skin. Another four incisions were made, perpendicular to the first incision. The incisions were made going in the lateral direction on the left side, equidistant to each other. In was made away from the pig’s midline. The flaps of skin were retracted laterally, exposing the rib cage. The ventral part of the rib cage was then cut out and moved to the lateral direction, exposing the inner parts of the thoracic cavity. This was done for both the right and left part of the ventral part of the ribs. The organs were then analyzed and cataloged. The small intestines were the first organ to be removed. The small intestines were disconnected from the large intestine. The small intestine was then excised and cataloged. The membrane in the small intestine was then cut, allowing the small intestines to be measured. The large intestine was then excised by disconnecting the rectum from the anal sphincter. After removing the small intestines, the underlying kidneys were now exposed. The positions of the kidneys were documented for later analysis. The posterior peritoneal sac was then dissected from the kidneys. The kidneys were then excised. Once the kidneys were removed, the thoracic organs were excised. The heart was the first organ from the thoracic cavity to be removed. Before any incisions, the position of the heart was documented for later incisions. The pericardial sac was incised and dissected from the myocardium. The heart was then dissected. After the heart was removed, the lungs were to be excised. The lungs were accidentally punctured, causing the diaphragm to collapse. The trachea and connective tissue were removed, allowing the excision of the lungs. After discarding the lungs, incisions were made around the diaphragm. This allowed the diaphragm to separate from the ribs. The organs left in the abdominal cavity were excised. The next organ to be excised was the liver. The liver was connected by the umbilical vein and connective tissue. The umbilical vein was transected and the connective tissues were dissected. After dissecting the connective tissues, the liver was excised. Removing the liver revealed the stomach. The esophagus was cut proximal to the stomach, which allowed the stomach to be excised. Once the thoracic and abdominal organs were removed, the eyeballs were excised. The skin surrounding the eyeballs was removed. Then a scalpel was inserted inside the eye socket. The blade cut around the eye ball, allowing the eyeball to be removed, intact, from the socket. This process was repeated on the other eye. After removing all the organs, the heart was split in half. An incision was made on the mid sagittal plane. This transected the heart into two pieces.
Results
While analyzing the external features of the fetal pig, we noticed that the skin was a light pink in color, soft and firm skin, covered in many light colored hairs. The fetal pig’s body was approximately 30cm long. The pig had four limbs and one tail (see figure 1). The pig had two eyes that were located anterior to the ears and had two ears located on the lateral sides of the head. The snout of the pig, located at the anterior part of the face, had two nostrils (see figure 2). The mouth was located inferior to the snout and contained a tongue that measured about 8cm (see figure 3).
Figure 1. Measuring pig’s head Figure 2. Pig’s facial features
After retracting the skin, the rib cage was exposed (see figure 4). Once the ventral part of the ribs was cut off, the thoracic and abdominal cavities were exposed (see figure 5). The thoracic cavity consists of the rib cage, the lungs, and the heart. Figure 3.
Pig’s tongue Figure 4. Rib cage being exposed
The lungs were a mix of gray and dark red (see figure 6). The lungs were easy to rip and very delicate. The lungs were located dorsal to the heart. There was a tube that was connected to the trachea. This tube was located at the medial part of the lungs. The lungs had six lobes in total, which meant each lung had three lobes. The lungs measured about 8cm in length. Figure 5. Thoracic and abdominal cavities Figure 6. The lungs
The heart was a light pink color and was shaped like an acorn (see figure 7). The heart was located ventral to the lungs and in the medial part of the thoracic cavity. An incision was made on the heart in the mid sagittal plane. The heart was transected into two pieces. The four chambers of the heart could be
seen. The stomach was a mix of green and brown. The stomach was wrinkly and very soft. The stomach was located dorsal to the liver. If you looked very closely at the stomach you would be able to see the pyloric sphincter. The liver was light pink in some areas and grayish in some areas (see figure 8). The liver was very soft and delicate. It was shaped like a deformed bean. The liver was located in the superior right of the abdominal cavity. The liver was connected to the umbilical vein. The liver measured about 6cm. Figure 7. The heart Figure 8. The liver
The small intestines were a combination of brown and gray (see figure 9). The small intestines were located in the inferior part of the abdominal cavity. The small intestines were all mushed inside the body so they could fit, but once they were taken out and untangled, the intestines measured about 167.64cm. The top of the small intestines, the duodenum, was connected to the stomach. The small intestine was also connected to the secum. The small intestine looks like a chord that has been all tangled. The kidneys were a light gray. The kidneys were located dorsal to the small intestine (see figure 10). The kidneys were soft and smooth. They looked like beans. The ureters could be seen going entering and exiting the kidneys. Figure 9. The small intestines Figure 10. The kidneys
The large intestine was light green in some locations and darker green in other locations. The large intestine was located lateral from the small intestines. The large intestine was soft and mushy. When cut open it, liquid and pig feces came out. Discussion
In the beginning, two of the dissectors were very nervous to begin the operation. One of the dissectors couldn’t stand the sight. The sight of seeing a dead pig in front of the dissectors caused some dissectors to get very uncomfortable. Trying to make an incision gave the dissectors a big surprise. The dissectors expected the skin to be easy to cut with a scalpel. Instead the dissectors had to use scissors to continue cutting the ventral side of the pig. The dissectors were not sure how deep to go when cutting the skin, that they accidently punctured the lungs. This caused the diaphragm to collapse. Curiosity took over the dissectors and caused the dissectors to be eager to continue making incisions.
When the pig was opened up, the dissectors were surprised to see how similar the inside of a pig was to a human. It was amazing to see the rib-cage cover and protect all the organs. Another shock the dissectors had was when the small intestines were removed from the body. The dissectors measured the length of the small intestines and found out that the length was about five and a half feet (167.64cm). The dissectors pictured the small intestines to be a pinkish color, but were astonished to find that it was more of brownish color. Another surprise for the dissectors was the size of the heart. The heart was imagined to be smaller than an acorn, but it turned out to be bigger than an acorn. The heart was expected to be more a dark red color, but it was more of a light pink. The dissectors committed an error when cutting the heart open, but the four chambers were still visible. It was expected that the chambers would be bigger than seen. It was harder than imagined to take out the eye from the socket. The dissectors thought they could stick the scalpel in and cut around the eye, but to their amazement, it took a lot of hard work to even get close to getting the eye out. The dissectors expected the eye to be really squishy and easy break. It was surprising for them to feel how hard the head was. The dissectors expected it to be softer, like a newborn’s head. Instead it was as hard as the cover of a binder. Finally, it was fascinating for the dissectors to see how similar the placement of the organs was to a human. The organs appeared to be scaled down models of real human organs. It was a marvelous sight for the dissectors.
References
1. Science Museum Brought to Life, http://www.sciencemuseum.org.uk/broughttolife/techniques/dissection.aspx
2. Encyclopedia Britannica, http://www.britannica.com/EBchecked/topic/626818/Andreas-Vesalius
Written by Jason Camacho
Contributors:
Anthony Camiccia
Ivy Topzands
Aleksandra Ivanova
J.Immel, Ph.D.
Introduction
Many scientists are experts when it comes to the placement of the organs in the human and animal body. Scientists can point anywhere and name the organ closest to it, but how do the scientists know exactly where each organ is? How do the scientists know the number of organs that are in your body? How do they know all this? Well, scientists know all about the anatomy of humans and animals because of a procedure called dissection. Dissection is when people cut open and analyze the structures and relations inside. In this situation a fetal pig …show more content…
was cut open and analyzed1. Dissection has been around as early as the third century B.C. The dissections were being carried out by the Greek physicians Herophilus of Chalcedon and Erasistratus of Chios. During these times, it was against Roman law to dissect a human a body, so many physicians, including Galen, were forced to work with only animals. Because of this, many physicians dissected various types of animals, assuming they had the same anatomy as the human. Eventually, the laws changed and human dissection was now legal. With human dissection being legal, many physicians performed human dissections and discovered many new things about the human anatomy1. A man called Andreas Vesalius was an important figure in the history of dissection.
This man is known as the founder of the human anatomy. Vesalius was born on December 31, 1554 in Brussels, Belgium and died on October 15, 1564 in Zakynthos, Venetian Ionian Islands, Greece. Vesalius was a physician who changed biology and practice of medicine by clearly and carefully describing the human anatomy. He wrote his own anatomy textbook using his own observations he took when dissecting humans. Vesalius was from a family of physicians and pharmacists. He decided to follow the family tradition and went to medical school. In 1537, he got his M.D. degree and became a lecturer in surgery. He was responsible to giving anatomical demonstrations. For the first few years he followed Galen’s methods and theories, but eventually he decided to use his own method. By using his own method, he discovered that Galenic anatomy had not been based off the dissection of the human body. Gale came up with the human anatomy by conclusions based from dissections made on varies types of animals. Vesalius also accurately described the muscles in the human body. He described where the muscles were located and what their job was. Vesalius was a man who discovered so much about human anatomy that he became a figure in the history of …show more content…
dissection2. Materials and Methods
Materials
One fetal pig One waxed aluminum container Two pieces of string One scalpel One pair of scissors One straight probe One bent probe One pair of forceps One eyedropper Plastic ruler
Method
First, the pig was received and carefully placed on the aluminum container. The pig was placed down, so that the ventral side was facing up. The limbs were then abducted and tied with string to the pan. Once the pig was tightly secured to the pan, the pig was measured. The external features of the pig were analyzed and cataloged. An incision was made using the scalpel. It was made on the superior sternum on the ventral surface. Scissors were then used to cut in the proximal and distal direction at the same duration. Scissors were then used to cut around the left side of the umbilical cord. We continued cutting inferior of the umbilical cord. The same process was repeated, except used a scalpel to cut deeper and depart the skin. Another four incisions were made, perpendicular to the first incision. The incisions were made going in the lateral direction on the left side, equidistant to each other. In was made away from the pig’s midline. The flaps of skin were retracted laterally, exposing the rib cage. The ventral part of the rib cage was then cut out and moved to the lateral direction, exposing the inner parts of the thoracic cavity. This was done for both the right and left part of the ventral part of the ribs. The organs were then analyzed and cataloged. The small intestines were the first organ to be removed. The small intestines were disconnected from the large intestine. The small intestine was then excised and cataloged. The membrane in the small intestine was then cut, allowing the small intestines to be measured. The large intestine was then excised by disconnecting the rectum from the anal sphincter. After removing the small intestines, the underlying kidneys were now exposed. The positions of the kidneys were documented for later analysis. The posterior peritoneal sac was then dissected from the kidneys. The kidneys were then excised. Once the kidneys were removed, the thoracic organs were excised. The heart was the first organ from the thoracic cavity to be removed. Before any incisions, the position of the heart was documented for later incisions. The pericardial sac was incised and dissected from the myocardium. The heart was then dissected. After the heart was removed, the lungs were to be excised. The lungs were accidentally punctured, causing the diaphragm to collapse. The trachea and connective tissue were removed, allowing the excision of the lungs. After discarding the lungs, incisions were made around the diaphragm. This allowed the diaphragm to separate from the ribs. The organs left in the abdominal cavity were excised. The next organ to be excised was the liver. The liver was connected by the umbilical vein and connective tissue. The umbilical vein was transected and the connective tissues were dissected. After dissecting the connective tissues, the liver was excised. Removing the liver revealed the stomach. The esophagus was cut proximal to the stomach, which allowed the stomach to be excised. Once the thoracic and abdominal organs were removed, the eyeballs were excised. The skin surrounding the eyeballs was removed. Then a scalpel was inserted inside the eye socket. The blade cut around the eye ball, allowing the eyeball to be removed, intact, from the socket. This process was repeated on the other eye. After removing all the organs, the heart was split in half. An incision was made on the mid sagittal plane. This transected the heart into two pieces.
Results
While analyzing the external features of the fetal pig, we noticed that the skin was a light pink in color, soft and firm skin, covered in many light colored hairs. The fetal pig’s body was approximately 30cm long. The pig had four limbs and one tail (see figure 1). The pig had two eyes that were located anterior to the ears and had two ears located on the lateral sides of the head. The snout of the pig, located at the anterior part of the face, had two nostrils (see figure 2). The mouth was located inferior to the snout and contained a tongue that measured about 8cm (see figure 3).
Figure 1. Measuring pig’s head Figure 2. Pig’s facial features
After retracting the skin, the rib cage was exposed (see figure 4). Once the ventral part of the ribs was cut off, the thoracic and abdominal cavities were exposed (see figure 5). The thoracic cavity consists of the rib cage, the lungs, and the heart. Figure 3.
Pig’s tongue Figure 4. Rib cage being exposed
The lungs were a mix of gray and dark red (see figure 6). The lungs were easy to rip and very delicate. The lungs were located dorsal to the heart. There was a tube that was connected to the trachea. This tube was located at the medial part of the lungs. The lungs had six lobes in total, which meant each lung had three lobes. The lungs measured about 8cm in length. Figure 5. Thoracic and abdominal cavities Figure 6. The lungs
The heart was a light pink color and was shaped like an acorn (see figure 7). The heart was located ventral to the lungs and in the medial part of the thoracic cavity. An incision was made on the heart in the mid sagittal plane. The heart was transected into two pieces. The four chambers of the heart could be
seen. The stomach was a mix of green and brown. The stomach was wrinkly and very soft. The stomach was located dorsal to the liver. If you looked very closely at the stomach you would be able to see the pyloric sphincter. The liver was light pink in some areas and grayish in some areas (see figure 8). The liver was very soft and delicate. It was shaped like a deformed bean. The liver was located in the superior right of the abdominal cavity. The liver was connected to the umbilical vein. The liver measured about 6cm. Figure 7. The heart Figure 8. The liver
The small intestines were a combination of brown and gray (see figure 9). The small intestines were located in the inferior part of the abdominal cavity. The small intestines were all mushed inside the body so they could fit, but once they were taken out and untangled, the intestines measured about 167.64cm. The top of the small intestines, the duodenum, was connected to the stomach. The small intestine was also connected to the secum. The small intestine looks like a chord that has been all tangled. The kidneys were a light gray. The kidneys were located dorsal to the small intestine (see figure 10). The kidneys were soft and smooth. They looked like beans. The ureters could be seen going entering and exiting the kidneys. Figure 9. The small intestines Figure 10. The kidneys
The large intestine was light green in some locations and darker green in other locations. The large intestine was located lateral from the small intestines. The large intestine was soft and mushy. When cut open it, liquid and pig feces came out. Discussion
In the beginning, two of the dissectors were very nervous to begin the operation. One of the dissectors couldn’t stand the sight. The sight of seeing a dead pig in front of the dissectors caused some dissectors to get very uncomfortable. Trying to make an incision gave the dissectors a big surprise. The dissectors expected the skin to be easy to cut with a scalpel. Instead the dissectors had to use scissors to continue cutting the ventral side of the pig. The dissectors were not sure how deep to go when cutting the skin, that they accidently punctured the lungs. This caused the diaphragm to collapse. Curiosity took over the dissectors and caused the dissectors to be eager to continue making incisions.
When the pig was opened up, the dissectors were surprised to see how similar the inside of a pig was to a human. It was amazing to see the rib-cage cover and protect all the organs. Another shock the dissectors had was when the small intestines were removed from the body. The dissectors measured the length of the small intestines and found out that the length was about five and a half feet (167.64cm). The dissectors pictured the small intestines to be a pinkish color, but were astonished to find that it was more of brownish color. Another surprise for the dissectors was the size of the heart. The heart was imagined to be smaller than an acorn, but it turned out to be bigger than an acorn. The heart was expected to be more a dark red color, but it was more of a light pink. The dissectors committed an error when cutting the heart open, but the four chambers were still visible. It was expected that the chambers would be bigger than seen. It was harder than imagined to take out the eye from the socket. The dissectors thought they could stick the scalpel in and cut around the eye, but to their amazement, it took a lot of hard work to even get close to getting the eye out. The dissectors expected the eye to be really squishy and easy break. It was surprising for them to feel how hard the head was. The dissectors expected it to be softer, like a newborn’s head. Instead it was as hard as the cover of a binder. Finally, it was fascinating for the dissectors to see how similar the placement of the organs was to a human. The organs appeared to be scaled down models of real human organs. It was a marvelous sight for the dissectors.
References
1. Science Museum Brought to Life, http://www.sciencemuseum.org.uk/broughttolife/techniques/dissection.aspx
2. Encyclopedia Britannica, http://www.britannica.com/EBchecked/topic/626818/Andreas-Vesalius