Fetal Pig Dissection!

1
Fetal Pig Dissection!

• Work in Groups of 3-4
• Get out lab books and lab packets!

2
Fetal Pig Dissection Day 1

• Getting Started!
• Obtain the following materials
• 1 fetal pig per group
• 1 large dissection pan
• 2 pieces of string - 25-30 inches long
• 2 good scalpels
• 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. Empty pig
  and contents into sink. THROW AWAY inner bag
  into the GREEN trash
• Rinse off pig well. Towel dry and place in a
  dissection tray

4
External Observations
Scrotum

• 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!

BOY!
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 a scalpel make a SUPERFICIAL
  midsaggital 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.
  Avoid the staples on one side of the pig
• 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 scapel 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
• Its 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

• 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
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 a SHARP scalpel remove all muscle and
  tissue overlying the larynx and trachea

Larynx
Trachea
11
Neck Blood Vessels pg. 418

• Using a BLUNT PROBE 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

• 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.

Superior Vena Cava
Right Lung
Left Lung
13
Cardiovascular SystemSuperior 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 listed on Page 13 of your lab
packet!

• Use pg. 404 pg. 409 in your lab books for help
• 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 GREEN trash.
• Throw any PIG TISSUE WASTE in the RED trash
• Rinse pig under water and clean both external and
  internal areas.
• Spray pig with cavicide (in white spray bottle)
  inside and out!
• Put pig in your saved plastic bag and secure with
  rubber band.
• Write the pigs name (or group name) on the bag
  in permanent marker.
• Place bagged pig in the tray.
• Spray down your table with cavicide or simple
  green!

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 SystemSuperior Vena Cava,
Pulmonary Trunk Aortic Arch
Superior Vena Cava
Aortic Arch
Pulmonary Trunk
Right Lung
Left Lung
26
Cardiovascular SystemInferior Vena Cava
Abdominal Aorta
Mesentery
Small Intestine
Inferior Vena Cava
Abdominal Aorta
Rectum
27
Ready to clean up?

• Cut off strings throw away in GREEN trash.
• Throw any PIG TISSUE WASTE in the RED trash
• Rinse pig under water and clean both external and
  internal areas.
• Spray pig with cavicide (in white spray bottle)
  inside and out!
• Put pig in your saved plastic bag and secure with
  rubber band.
• Write the pigs name (or group name) on the bag
  in permanent marker.
• Place bagged pig in the tray.
• Spray down your table with cavicide or simple
  green!