Fetal Pig Dissection!

1. Fetal Pig Dissection! • !

2. Fetal Pig Dissection – Day 1 Getting Started! Obtain the following materials: 1 fetal pig per group 1 large dissection pan Scissors 2 BLUNT Probes Forceps (tweezers)

3. Initial Prep • Open up the plastic bag – • KEEP the outer bag AND the rubber band! • Cut open the inner bag over the sink.

4. External Observations Scrotum BOY! • Look for the umbilical cord • Try to find the umbilical arteries/veins that connected its blood supply to mom via the placenta • External nares(remember what those are?) • Tongue • Boy or Girl? • Look under the tail. • If all you see it an anus (hole) then a SMOOTH swollen sac of skin – you have found the SCROTUM and you have a boy! • If you see an anus (hole) plus an obvious folded area of skin. You have found the GENITAL PAPILLA and you have girl! Anus Genital Papilla Anus GIRL!!!

5. Securing your Pig to the tray • Use the 2 pieces of string to secure your pig to the dissecting tray

6. Incision Time 1. Take the sissors– make a SUPERFICIAL incision from chin to umbilical cord 2. Then use scissors to cut along either side of the umbilical cord to create a “flap” 3. & 4. Use scissors to make 2 lateral cuts. Also be careful not to demolish the DIAPHRAGM at the base of the rib cage!

7. Incision Time 3. & 4. Use scissors to make 2 lateral cuts. Avoid the staples on one side of the pig • Also be careful not to demolish the DIAPHRAGM at the base of the rib cage! Diaphragm

8. Separate Skin from rib cage • Using your scissors– separate the skin of the chest area off of the rib cage. • You will have to cut through muscle and connective tissue to do this • It’s like skinning raw chicken! • Using scissors – cut of each half of the rib cage. You should end up with 2 large chunks of ribs in your tray

9. Diaphragm Diaphragm • Use scissors to separate the diaphragm from the floor of the rib cage. • You should be left with one big “flap” of Diaphragm that hangs over the liver and stomach (see d page 409 of lab book) Diaphragm

10. Exposing Larynx and Trachea – pg. 409 • Using scissors – cut off any remaining pericardial sac that might be covering the heart. • Place any pieces in your tray for later disposal • Using the scissors– remove all muscle and tissue overlying the larynx and trachea Larynx Trachea

11. Neck Blood Vessels – • Using a BLUNTPROBE – carefully probe on either side of the trachea until you expose • 1 PINK common carotid artery on each side • 2 BLUE jugular veins on each side • These are the internal and external jugular veins Common Carotid Artery Internal Jugular Vein External Jugular Vein

12. Heart Superior Vena Cava • Using a combination of scalpel and scissors: • Cut off the pericardial sac that surrounds the heart • Be careful not to cut off any important blood vessels! • Also not the texture and position of the RIGHT AND LEFT LUNGS. Right Lung Left Lung

13. Cardiovascular System:Superior Vena Cava, Pulmonary Trunk & Aortic Arch Superior Vena Cava Aortic Arch Pulmonary Trunk Right Lung Left Lung

14. What now? Locate all Respiratory & Digestive System organs • Note: do NOT find the urinary organs yet – we will do this later. • When your group thinks it has found everything – call me over so I can review it with you!

15. Ready to clean up? • Cut off strings – throw away in trash. • Throw any PIG TISSUE WASTE in the trash • Put pig in your saved plastic bag and secure with rubber band. • Write the pig’s name (or group name) on the bag in permanent marker. • Place bagged pig in the tray. • Spray down your table soap and water, dry…

16. Respiratory System • Make sure you can locate: • External nares • Larynx • Trachea • Diaphragm • lungs

17. Digestive System • Be sure you can locate: • Tongue • Esophagus • Stomach • Liver • Gallbladder • Small intestine • Large Intestine • Pancreas • Mesentery • Rectum

18. Digestive System Note: the following are not shown, but you need to know where they are: Tongue, esophagus, stomach, pancreas Liver Large intestine Gallbladder Mesentery Small intestine Rectum

19. Fetal Pig Dissection – Day 2

20. Urinary System • Do NOT cut out the intestines to dissect the urinary system! • Push the intestines to one side and use a scalpel or blunt probe to remove the connective tissue around each kidney and ureter • Note the ALLANTOIC BLADDER Rectum Left Kidney Right Kidney Left Ureter Right Ureter Allantoic Bladder

21. Reproductive System - MALE Allantoic Bladder Spermatic Cord Penis testes Spermatic Cord Epididymis Epididymis testes

22. Reproductive System - FEMALE Uterine Horn Uterine Horn Ovary Ovary Uterine Body Allantoic Bladder

23. Cardiovascular System – Heart & Spleen heart Spleen

24. Cardiovascular System – page 418 • 1 PINK common carotid artery on each side • 2 BLUE jugular veins on each side • These are the internal and external jugular veins Common Carotid Artery Internal Jugular Vein External Jugular Vein

25. Cardiovascular System:Superior Vena Cava, Pulmonary Trunk & Aortic Arch Superior Vena Cava Aortic Arch Pulmonary Trunk Right Lung Left Lung

26. Cardiovascular System:Inferior Vena Cava & Abdominal Aorta Mesentery Small Intestine Inferior Vena Cava Abdominal Aorta Rectum

27. Ready to clean up? • Cut off strings – throw away in trash. • Throw any PIG TISSUE WASTE in the trash • Rinse pig under water and clean both external and internal areas. • Spray down your table with soap and water….