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Lab Handout #4
East Los Angeles College
Cat dissection
Introduction: The skeletal muscles of all mammals are named in a similar fashion. Some muscles that are separated
in animals are fused in humans and some muscles present in animals are absent in humans. This exercise involves
dissection of the cat musculature to improve your knowledge of the human muscular system.
The following are the steps to the proper and orderly preparation and skinning of the cat to optimize its use for
dissection throughout the rest of the semester. At the conclusion of this and each dissection, thorough cleansing of
instruments, desks, sinks and floors is extremely important. Please be rigorous in your cleanliness. Use a sponge for
all steps of cleansing except the very last. Use a single paper towel to finish drying the cleansed desk.
1. LABEL BAG
2. Do not dispose of this fluid when you remove the cat; the fluid prevents the cat from drying out: At the sink,
with rubber gloves, carefully cut open plastic bag. Remove cat tail first into the sink so that excess
preservative fluid remains in the bag. Squeeze out excess fluid from the cat's fur by milking down from head
to tail. Set aside the bag with the cat juice so to keep the cat muscle moist for later use.
Preparing for the cat dissection: Incisions to be made in skinning a cat.
1. Place the cat ventral side down on the dissecting tray.
2. With a scalpel, make a short, shallow incision in the midline of the neck just to penetrate the skin
3. From this point on, use scissors & continue the cut from the length of the back to the sacrolumbar region,
stopping at the tail
4. From the dorsal surface of the tail region, continue the incision around the tail, encircling the anus and
genital organs. The skin will not be removed from this region.
5. Beginning again at the dorsal tail region, make an incision through the skin down each hind leg nearly to the
ankle. Continue the cuts completely around the ankles
6. Return to the neck. Cut the skin around the neck.
7. Cut down each foreleg to the wrist. Completely cut through the skin around the wrists.
8. Now free the skin from the superficial fascia that binds it to the underlying structure. With one hand, grasp
the skin on one side of the midline dorsal incision. Then, using your fingers or a blunt probe. Brea, through
the "cottony" CT fibers to release the skin from the muscle beneath. Work toward the ventral surface and
then toward the neck
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Lab Handout #4
East Los Angeles College
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Lab Handout #4
East Los Angeles College
Muscle Dissection
1. Listed below are the major muscles that you need to identify from your cats. For you dissection, you will need
to remove any excess fat and fascia that may cover the muscles. Be careful as you remove these connective
tissues-you do not need to remove muscle tissue during this process. Muscles are extremely thin, so be careful
as you remove fat and fascia from the cat. As you work on the cat, try to separate the muscles along their
natural lines. Do not cut or remove any muscles. Be able to identify by sight, all of the muscles listed on this
sheet.
2. Useful Website http://www.mhhe.com/biosci/ap/cat_dissect/cat_demo/muscular_system/muscle_index.html
Cat Muscle Dissection and Identification
Chest Muscles
Muscles of Abdominal
Wall
Superficial Back Muscles
Muscle of the shoulder
Muscles of the brachium
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Superficial
1. xiphihumeralis
2. pectoralis major
3. pectoralis minor
4. pectoantebrachialis
Deep
5. serratus ventralis
6. anterior scalenus
7. middle scalenus
8. posterior scalenus
1. EXTERNAL OBLIQUE
2. INTERNAL OBLIQUE
3. TRANSVERSUS ABDOMINIS
4. RECTUS ABDOMINIS
1. Spinotrapezius
2. Acromiotrapezius
3. Clavotrapezius
4. Spinodeltoid
5. Acromiodeltoid
6. Clavodeltoid (clavobrachialis)
7. latissimus dorsi
1. supraspinatus
2. infraspinatus
3. teres minor
4. subscapularis
5. levator scapulae ventralis
6. teres major
7. rhomboids
8. rhomboid capitis
9. splenius
1. biceps brachii
2. brachialis
3. triceps brachii (long head)
4. triceps brachii (medial head)
5. triceps brachii ((lateral head)
6. epitrochlearis
Lab Handout #4
East Los Angeles College
Muscles of antebrachium
& Manus
Muscles of the Hip
Muscles of Thigh
(hindlimb)
1.
2.
3.
4.
5.
6.
7.
8.
9.
1.
2.
3.
1.
2.
3.
4.
5.
6.
Muscles of the shank (leg)
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7.
8.
9.
10.
1.
2.
3.
4.
5.
6.
7.
8.
brachioradialis
extensor carpi radialis longus & brevis
extensor digitorum communis
extensor digitorum lateralis
extensor carpi ulnaris
pronator teres
flexor carpi radialis
palmaris longus
flexor carpi ulnaris
gluteus medius
gluteus maximus
caudofemoralis
sartorius
gracillis
tensor fascia lata
fascia lata (iliotibial band)
quadriceps femoris
• vastus lateralis
• vastus medialis
• vastus intermedius
• rectus femoris
Hamstrings
a. biceps femoris
b. semitendinosus
c. semimembranous
Iliopsoas
Pectineus
adductor femoris
adductor longus
gastrocnemius
soleus
plantaris
calcaneal (Achilles’) tendon
fibularis (peroneus)
tibialis anterior
extensor digitorum longus
flexor digitorum longus
Lab Handout #4
East Los Angeles College
Major differences between Human & Cat Muscles
pectoralis major
pectoralis minor
pectoantebrachialis
Xiphihumeralis
clavotrapezius,
acromiotrapezius,
spinotrapezius
caudofemoralis
gluteus maximus
sartorius
adductor femoris (cat)
epitrochlearis
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larger in human, smaller in cat
smaller in human, larger in cat
not present in human
not present in human
three muscles in cat, one muscle in human (trapezius)
not present in human
larger than gluteus medius in humans, smaller than gluteus medius in cat
wide muscle in cat, narrow muscle in human
adductor magnus (human)
not present in human