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Anatomy I (Fall) > Vasculature and Nerves > Flashcards

Flashcards in Vasculature and Nerves Deck (499):
1

How many cervical spinal nerves in the dog?

Eight

2

Where does the first cervical spinal nerve pass through?

Lateral vertebral foramen of the atlas (Transverse foramen in wing of the caudal vertebral body of the atlas)

3

Where does the eight cervical spinal nerve pass through?

The intervertebral foramen between the 7th cervical vertebra and 1st thoracic vertebra.

4

Which are larger - dorsal or ventral branches of the spinal nerves?

Ventral

5

What do dorsal branches of the spinal nerves innervate?

Structures dorsal to the vertebrae.

6

Where will you find the 2nd cervical nerve?

Between:
Mastoid part of the cleidocephalicus
Omotransversarius
Deep to platysma
Dorsal to external jugular vein

7

What does the 2nd cervical nerve innervate?

Branches into two:
Great auricular nerve: skin of the neck, the ear, and back of the head.
Transverse cervical nerve: Skin of the cranioventral part of the neck

8

What vessels is the external jugular vein formed by?

Facial components: Linguofacial (ventral) and maxillary (dorsal) veins. Maxillary can be distinguished by mandibular lymph nodes lying on either side.
Brachial components: Omobrachaial (dorsal) and cephalic (ventral) veins

9

Mandibular salivary gland

Dorsal to the mandibular LNs.

10

Mandibular lymph nodes

Receive lymph drainage from the cutaneous areas of the head, neck, and thoracic limb
Ventral to the mandibular salivary gland, deep to the cleidocephalicus and omotransversarius.

11

Where do you find the accessory cranial nerve?

Also called the 11th cranial nerve
Emerges below the sternocephalicus, runs along the dorsal border of the omotransversarius, terminates in the trapezius

12

What does the accessory cranial nerve innervate?

Only motor nerve of the trapezius.
Also supplies:
Omotransversarius
Cleidocephalicus (mastoid and cervical parts)
Sternocephalicus

13

Third, Fourth, and Fifth cervical spinal nerves

Distributed segmentally to the muscles and skin of the neck

14

Vagosympathetic nerve trunk

Within the carotid sheath, medial to the common carotid artery.

15

Medial retropharyngeal lymph node

Lies ventrolateral to the carotid sheath
Opposite the larynx

16

Branching pattern of the dorsal intercostal arteries

Do not confuse with dorsal branch of the artery
First three dorsal arteries: from branch of the costocervical trunk
Last 9 dorsal arteries: from aorta
Two lateral cutaneous branches (one dorsal, one ventral) that perforate both intercostal muscles

17

Ventral intercostal arteries

Ventral intercostal artery anastomoses with the dorsal intercostal artery
Perforating branch that perforates just the internal intercostal muscles near the sternum.

18

Dorsal branch of the arteries of the intercostal space

Supplies the epaxial muscles
Do not confuse with dorsal intercostal arteries.

19

Ventral branch of the arteries of the intercostal space

Anastomoses with the dorsal intercostal artery.

20

Veins of the intercostal spaces

Will follow in the same pattern as the arteries of the intercostal spaces.

21

What do the lateral branches of the dorsal intercostal arteries supply?

Cutaneous structures
Example: thoracic mammae

22

What do the perforating branches of the ventral intercostal arteries supply?

Cutaneous structures
Example: thoracic mammae

23

Branching pattern of the intercostal nerves

Dorsal, lateral, and ventral branches
Dorsal: innervates epaxial muscles.
Lateral: Becomes the dorsal lateral cutaneous branch
Ventral: A lateral branch that perforates both intercostal muscles and a ventral cutaneous branch that perforates just the internal intercostal near the sternum.

24

What are the cranial thoracic mammae supplied by?

Fourth, fifth, and sixth ventral and lateral cutaneous vessels and nerves (from the intercostals)
Branches of the lateral thoracic vessesls (from the axillary vessels)

25

What are the caudal thoracic mammae supplied by?

Sixth and seventh cutaneous nerves and vessels
Cranial superficial epigastric vessels

26

What do the intercostal vessels and nerves become after they pass through the intercostals?

Cutaneous vessels and nerves.

27

Axilla

Armpit.
Bounded by: Pectorals and serattus ventralis.
Contains: brachial plexus

28

Where do you find the lateral thoracic vessels and nerve?

In the axilla
Between the latissiumus dorsi and deep pectorals

29

What does the lateral thoracic nerve innervate?

Motor to the cutaneus trunci.

30

What does the lateral thoracic nerve consist of?

Branches of the 8th cervical and 1st thoracic spinal nerves.

31

What do the lateral thoracic vessels consist of?

Branches of the axillary artery and vein.

32

What do the lateral thoracic vessels supply?

Muscle, skin, subcutaneous tissue, and cranial thoracic mama.

33

Axillary lymph node

Drains the afferent lymph vessels of the thoracic wall and deep structures of the limb.
Dorsal to the deep pectoral

34

Cranial epigastric artery

Terminal branch of the internal thoracic artery
Emerges from costal arch
Runs caudally on the deep surface of the rectus abdominis
Gives rise to cranial superficial epigastric artery

35

Cranial superficial epigastric artery

From the cranial epigastric artery
Perforates the rectus abdominis
Runs caudally over external surface of rectus abdominis
Branches terminate in rectus abdominus.

36

What does the cranial superficial epigastic artery supply?

Skin over the rectus abdominis
Caudal thoracic mammae
Cranial abdominal mammae

37

Transversus thoracis

Flat muscle on deep ventral surface of costal cartilage 2-8.
Attachments: chostochondral junctions and sternum

38

Internal thoracic artery

3rd lateral branch off the brachiocephalic artery.
Supplies the phrenic nerve, the thymus, the mediastinal pleurae and the dorsal intercostal spaces.
Branch from the subclavian artery
Runs ventrocaudally through the cranial mediastinum
Anastomoses with ventral intercostal arteries on the medioventral surface of the thoracic cavity.
Terminatees in the musculophrenic and cranial epigastric arteries.

39

Pleurae

Serous membranes that cover the lungs and line the walls of the thorax.

40

Visceral pleura

Also called pulmonary pleura
Closely attach to the surfaces of the lungs and separate the two lobes.

41

Parietal pleura

Attached to the thoracic wall by endothoracic fascia
Three contiguous parts: costal, diaphragmatic, and mediastinal

42

Costal pleura

Covers inner surface of the ribs and associated intercostal and transverses thoracis muscles.

43

Diaphragmatic pleura

Covers cranial surface of the diaphragm.

44

Mediastinal pleura

Covers the sides of the partition between the two pleural cavities

45

Mediastinum

Two mediastinal pleurae and the space between them
Encloses the heart, lymph nodes, thymus, heart, aorta, trachea, and esophagus, as well as the vagus nerve and other nerves/vessels.
Can be divided into cranial, middle, dorsal, ventral, and caudal parts with the middle covering the heart and the others in relation to the heart.

46

Pericardial mediastinal pleura

Portion of the mediastinal pleura covering the heart.

47

Esophageal hiatus

Where the esophagus passes through the diaphragm
Connected by connective tissue, pleura, and peritoneum.

48

Plica venae cavae

Loose fold of pleura from the right caudal mediastinal portion of the pleural sac.
Surrounds the caudal vena cava.

49

Root of the lung

Also called the hilus of the lung.
The pleura, bronchi, vessels, and nerves that are all entering into the lung.

50

Pulmonary ligament

Between the caudal lung lobe and the mediastinum at the level of the esophagus.

51

Thymus

Bilobed compressed structure in the cranial mediastinum, over the surface of the pericardium when large.
Largest in young animals and atrophies with age.

52

Musculophrenic artery

Runs caudodorsally in the angle formed by the diaphragm and the lateral thoracic wall.

53

What artery supplies the thymus?

Internal thoracic artery.

54

What nerve innervates the trapezius?

Accessory cranial nerve.

55

Left lung lobes

Two:
Cranial lobe with cranial and caudal parts
Caudal lobe

56

Right lung lobes

Four:
Cranial lobe
Middle lobe (most lateral)
Caudal lobe
Accessory lobe (most medial)

57

Cardiac notch

On the right lung
Between the cranial and middle lobes of the lung
The fourth and fifth intercostal space

58

Principal bronchi

Bifurcation of the trachea to supply each lung.

59

Carina

Partition between the principal bronchi in the trachea.

60

Lobar bronchi

Divisions of the principal bronchi to supply the lobes of the lungs.

61

What is the clinical significance of the cardiac notch?

Heart is accessible for cardiac puncture here.

62

Aortic impression on the left lung

Most marked on the accessory lobe.

63

Tracheobronchial lymph nodes

Located at the bifurcation of the trachea and further down on the bronchi.
Do not confuse with mediastinal lymph nodes.

64

Where do the pulmonary veins drain? Do they carry oxygenated or deoxygenated blood?

Drain into the left atrium of the heart
Carry oxygenated blood

65

Pulmonary trunk

Supplies each lung with a pulmonary artery. Right pulmonary artery will be ventral to right principal bronchus.

66

Cranial vena cava

Drains into the right atrium
Formed by the union of the left and right brachiocephalic veins, and the right azygos vein.

67

Thoracic inlet

Union of the left and right brachiocephalic veins draining into the cranial vena cava.

68

Brachiocephalic veins

Formed by external jugular and subclavian veins

69

Azygos vein

Only the right vein develops in the dog
The last branch entering the cranial vena cava
Winds ventrocranially around the right lung
Collects blood from all of the dorsal intercostal veins as far cranially as the 3rd/4th intercostal space

70

Thoracic duct

Drainage from:
lymphatic capillaries
ducts to the venous system
left thoracic limb
left tracheal trunk
Drains into the left brachiocephalic vein

71

Cisterna chyli

Dilated structure that receives lymph drainage from the abdominal and pelvic viscera and the pelvic limbs.
Caudal to the thoracic duct and the thoracic duct continues from it.

72

Left tracheal trunk

Lymph drainage from the left side of the head and neck
Drains into the thoracic duct

73

Right tracheal trunk

Lymph drainage from the right side of the head and neck
Drains into the venous system at the right brachiocephalic vein.

74

Aorta

Large unpaired vessel from left ventricle
Two main parts:
Cranial aorta (to the diaphragm): Ascending aorta, aortic arch, and descending aorta
Caudal aorta (to the diaphragm

75

Coronary arteries

Branches of the ascending aorta that supply the heart muscle

76

Vessels from the ascending aorta

Coronary arteries

77

Vessels from the aortic arch

Brachiocephalic trunk
Left subclavian artery

78

Vessels from the descending aorta

8-9 dorsal intercostal arteries (first 3 from the costocervical trunk)

79

Brachiocephalic trunk

First branch from the aortic arch
Gives rise to left carotid artery and then terminates as the right carotid artery and the right subclavian artery.

80

Common carotid arteries

Both left and right come from the brachiocephalic trunk

81

Subclavian arteries

Right comes from the brachiocephalic trunk
Left is the second branch of the aortic arch
Both have similar branching after this point.

82

Vertebral artery

1st branch off of the subclavian artery
Supplies the cervical muscles and spinal branches spinal cord and its coverings via intervertebral foramina.

83

Costocervical trunk

2nd branch off the subclavian artery
Supplies the 1st/2nd/3rd intercostal spaces, muscles at the base of the neck, and muscles dorsal to the first few thoracic vertebrae.

84

Superficial cervical artery

3rd medial branch of the subclavian artery.
Supplies the base of the neck and the scapular region.

85

Bronchoesophageal artery

Supplies the esophagus
Arises from the 5th intercostal artery
Terminates in the bronchial arteries

86

Bronchial arteries

Supply the lungs

87

Phrenic nerves

Arises from the ventral branches of the 5th/6th/poss.7th cervical nerves
Innervate the diaphragm
Have both sensory and motor functions.

88

Central Nervous System

Brain and spinal cord

89

Peripheral Nervous System

Anything outside of the CNS
Cranial nerves, spinal nerves, and what they become.

90

Sensory nerves

Afferent nerves
Always pseudounipolar

91

Motor nerves

Efferent nerves
Somatic efferents (conscious, to skeletal muscle) are pseudounipolar
Visceral/autonomic efferents (unconscious, to smooth muscle) parasympathetic (rest and digest) or sympathetic (fight or flight) are multipolar and need two to reach the effector tissue

92

Ganglion

Gross enlargement of a nerve
Contains neuronal cell bodies

93

What are groups of neuronal cell bodies within the CNS called?

Nuclei

94

What are the two autonomic efferent neurons called as they travel to the effector tissue?

Preganglionic and postganglionic neurons.

95

What is another name for the sympathetic nervous system?

Thoracolumbar system

96

What is another name for the parasympathetic nervous system?

Craniosacral system

97

What humoral transmitter substance is released at sympathetic nerve endings?

Norepinephrine

98

What humoral transmitter substance is released at parasympathetic nerve endings?

Acetylcholine

99

Where are parasympathetic ganglia typically located?

In the wall of the structure being innervated.

100

Where are sympathetic ganglia typically located?

A short distance from the spinal cord.

101

Ventral root of the spinal cord

Efferent neurons

102

Dorsal root of the spinal cord

Afferent neurons

103

Spinal nerve

Joining of the ventral and dorsal roots of the spinal cord just at the edge of the vertebra at the level of the intervertebral foramen.

104

Ramus communicans

Also called the communicating branch
Leaves the ventral branch of the spinal nerve just after it starts
Joins the sympathetic trunk
Like all other nerves, multiple types of nerves. Mostly pre and post ganglionic sympathetic GVEs in these branches but may be others.

105

Sympathetic trunk ganglion

Peripheral nerve just lateral to the spinal column
A sympathetic trunk ganglion located at each point where a ramus communicants joins with the trunk, with cell bodies of postganglionic sympathetic neruons.

106

Splanchic nerves

Run through the sympathetic trunk
Form plexuses around the main blood vessels of the abdominal organs
Additional sympathetic ganglion within the plexuses (postganglionic cell bodies of the neurons that formed these nerves located here)

107

Describe the movement of a pair of sympathetic GVE neurons that innervate smooth muscles, sweat glands, and other strucutures located above the spinal cord.

1. Run down the ramus communicans
2. Synapse either with the first sympathetic trunk ganglion that they come across or move one or two ganglia cranially or caudally.
3. Postganglionic neuron runs back over through the ramus comminicans in the segment where the synapse occurred
4. Runs with a spinal nerve to the structures to be innervated.

108

What verterbrae have spinal nerves that feed into the sympathetic nervous system?

T1 - L4 or L5

109

Cranial cervical ganglion

Synapses of the preganglionic sympathetic neurons that supply the head.

110

Cervicothoracic ganglion

Enlargement of the sympathetic trunk lateral to the longus colli at the first intercostal space
Fusion of the caudal cervical ganglion and the first two or three thoracic ganglion.

111

Brachial plexus

Pathway through the axilla for the postganglionic axons to reach the thoracic limb.
Formed by the ventral branches of the (sometimes 5th)/6th/7th/8th cervical and 1st/2nd thoracic spinal nerves.
These intermix and differently named intermixed nerves leave from the plexus.

112

Vertebral nerve

From the cervicothoracic ganglion through transverse foramina to the heart and other thoracic structures.

113

Ansa subclavia

Division of the sympathetic trunk for it to loop around the subclavian artery. Unite at the middle cervical ganglion.
Many nerves leave this to supply the heart.

114

Middle cervical ganglion

Junction of the nasa and the vagosympathetic trunk. Many nerves leave this to supply the heart.

115

Cardiac nerves

Numerous
Leave the ansa subclavia and middle cervical ganglion to course to the heart.

116

Vagosympathetic trunk

Lies in the carotid sheath
Cranial cervical ganglion at its cranial end.
Combines with the vagus nerve (tenth cranial nerve).

117

Left and right recurrent laryngeal nerves

Left curves around the arch of the aorta
Right curves around the right subclavian artery
Both then run up the trachea and supply the larynx
Innervate the heart, esophagus, and trachea.
Longest peripheral nerves in the body, so early peripheral neuropathy is typically seen with trouble barking or swallowing.

118

Caudal laryngeal nerve

Termination of the recurrent laryngeal nerves in the larynx.

119

Ventral vagal trunk

Cranial termination of the dorsal and ventral vagus nerves on the esophagus, cranial to the heart.

120

Dorsal vagal trunk

Caudal termination of the dorsal and ventral vagus nerves dorsal to the esophagus near the diaphragm.

121

Dorsal and ventral vagus nerves

Division of each vagus nerve near the base of the heart.

122

Pericardium

Fibroserous covering of the heart
Three layers:
Outer: Pericardial mediastinal pleura
Fibrous pericardium
Inner: Parietal serous pericardium

123

Serous pericardium

Two layers
parietal layer - adheres to the fibrous pericardium (forms part of the pericardium)
visceral layer - adheres to the heart (considered part of the heart)

124

Pericardial cavity

Contains pericardial fluid between the parietal serous pericardium and visceral serous pericardium.

125

Phrenicopericardial ligament

Continuation of the fibrous pericardium to the sternum and the diaphragm.
Usually associated with adipose tissue.
Located in the ventral mediastinum.

126

Epicardium

Another name for visceral serous pericardium.

127

Auricular surface of the heart

Left side of the heart, can see both auricles from this side.

128

Atrial surface of the heart

Right side of the heart. Can generally only see the right auricle here.

129

Dorsal surface of the heart

Attachments of the great vessels

130

Apex of the heart

Ventrocaudal and slightly to the left in most hearts, part of the left ventricle.

131

Coronary Groove

Separates the ventricles from the atria on the atrial side of the heart.

132

Interventricular grooves

Paraconal interventraicular groove (auricular surface, oblique)
Subsinuosal interventricular groove (atrial surface)

133

Cranial surface of the heart

Right ventricle covers the left ventricle here.

134

Parts of the right atrium

Sinus venarum (main)
right auricle

135

How many openings into the right atrium? What are they?

Four.
1. Caudal vena cava
2. Coronary sinus
3. Cranial vena cava
4. Right atrioventricular orifice (holds the valve)

136

Interatrial septum

Medial wall of the heart separating the left and right atria.

137

Intervenous tubercle

Transverse ridge between the two caval openings in the right atrium
Serves to channel blood towards the right atrioventricular orifice.

138

Fossa ovalis

Slitlike depression caudal to the intervenous tubercle
Formed the foramen ovale between the right and left atria in the fetus (no need to send blood to the lungs)

139

Pectinate muscles

Interlacing muscular bands in the auricles and atria

140

Endocardium

Grossly: glistening surface on the inner surface of the heat
Microscopically: Simple squamous epithelium lining the inner part of the vessel.

141

Crista terminalis

Thick, semilunar smooth portion of the right atria at the entrance into the auricle. Pectinate muscles radiate from this band.

142

Pulmonary trunk

Leaves the right ventricle at the conus arteriosus to continue to the lungs.
At the left craniodorsal aspect of the heart.
Will then bifurcate into the left and the right pulmonary arteries.

143

Atrioventricular valve

Right and left
Both have two cusps, a septal and a parietal cusp.
Subsidiary leaflets found at the end of both cusps in the left and just the septal cusp in the right.

144

Chordae tendineae

Connect the cusps of the atrioventricular valves with the walls of the ventricles via the papillary muscles.

145

Papillary muscles

Conical muscle projections in the ventricles
Usually three or four
Attachments for the chordae tendineae.

146

Trabeculae carnae

Muscular irregularities of the interior of the ventricular walls.
More numerous in the right ventricle than in the left.

147

Trabecula septomarginalis

Muscular strand extending across the lumen of the right ventricle from the septal to the parietal wall, also anchored by a papillary muscle.

148

Pulmonary valve

Between the conus arteriosus and the pulmonary trunk
three semilunar cusps, each with a small fibrous nodule in the middle of them.

149

Valve of the foramen ovale

Remnant of the foramen oval
In the left atrium, directly across from the fossa ovalis in the right atrium.

150

ligamentum arteriosum

Fibrous connection between the pulmonary trunk and the aorta
Remnant of the patent ductus arteriosus to bypass the lungs in the fetus (funneled blood straight into the aorta).

151

Aortic valve

Between the left ventricle and the aorta.
Three semilunar cusps with fibrous nodules like the pulmonary valve.

152

Sinus of the aorta

Slight expansion of the aorta just cranial to the aortic valve.

153

Right coronary artery

Leaves the right sinus of the aorta.
Passes through coronary groove and often part of the subsinuosal interventricular groove.

154

Left coronary artery

Twice as large as the right coronary artery.
Leaves the left sinus of the aorta.
Two branches: circumflex branch and paraconal inter ventricular branch.

155

Circumflex branch of the left coronary artery

Passes through the subsinuosal interventricular groove and in the coronary sulcus.

156

Paraconal interventricular branch of the left coronary artery.

Passes through the paraconal interventricular groove.
Sends large rami over the surface of the left ventricle.
Septal branch that runs into the interventricular septum and supplies this.

157

Coronary sinus

Dilated terminal end of the great cardiac vein.

158

Great cardiac vein

Drains the coronary vessels back to the heart.
Starts in the paraconal interventricular sulcus.

159

Subclavian artery branches

1. Vertebral artery
2. Costocervical artey
3. Internal thoracic artery and superficial cervical artery
4. Continues as the axillary artery

160

What does the superficial cervical artery supply?

Superficial muscles of the base of the neck, superficial cervical lymph nodes, and the muscles of the scapula and shoulder.

161

What is the function of the superficial cervical lymph nodes?

Drain the afferent lymph vessels from the superficial part of the neck, caudal surface of the head, ear, and pharynx, and the thoracic limb.

162

What are the branches off the axillary artery?

External thoracic artery
Lateral thoracic artery
Subscapular artery
Cranial circumflex artery

163

What are the nerves that come out of the brachial plexus?

Suprascapular nerve
Subscapular nerve
Axillary nerve
Musculocutaneous nerve
Radial nerve
Median nerve
Ulnar nerve
Thoracodorsal nerve
Lateral thoracic nerve
Pectoral nerve

164

External thoracic artery

1st branch off the axillary artery.
(normal variation: may be off the same trunk as the lateral thoracic artery or superficial cervical artery)
Supplies the superficial pectorals.

165

Lateral thoracic artery

2nd branch off the axillary artery.
(normal variation: may be distal to the subscapular artery).
Supplies the latissimus dorsi, deep pectorals, cutaneus trunk, and thoracic mammae.

166

Subscapular artery

3rd branch off the axillary artery.
Three branches:
Thoracodorsal artery
Caudal circumflex humeral artery
Continuation of the subscapular artery (supplies the scapula).

167

Cranial circumflex artery

4th branch off the axillary artery.
(normal variation: may be distal or proximal to the subscapular artery).
Supplies the biceps brachia and the joint capsule of the shoulder

168

Thoracodorsal artery

Supplies the trees major and latissimus dorsi

169

Caudal circumflex humeral artery

Wraps around the cranial side of the humerus (can be seen under the deltoideus on the lateral side).
Supplies the triceps, deltoids, coracobrachialis, infraspinatus, and shoulder joint capsule.

170

Brachial artery

Continuation of the axillary artery over the humerus. Terminates in the median artery after the branch off of the common interosseous artery.
Branches into:
Collateral ulnar artery
Superficial brachial artery
Transverse cubital artery
Common interosseous artery

171

Collateral ulnar artery

1st branch off the brachial artery (across from a smaller bicipital artery)
Supplies the triceps, ulnar nerve, and the elbow

172

Superficial brachial artery

2nd branch off the brachial artery
More distally will anastomose with the cranial superficial antebrachial artery.
Supplies the dorsum of the forepaw

173

Transverse cubital artery

3rd branch off the brachial artery.
Supplies the elbow.

174

Cranial pectoral nerves

Derived from branches of the 6th/7th/8th cervical spinal nerves
Innervate superficial pectoral muscle.

175

Suprascapular nerve

Derived from 6th/7th cervical spinal nerves (Brachial plexus)
Passes directly across the scapular notch and so very susceptible to injury (sweeny in horses)
Innervates supraspinatus and infraspinatus

176

Subscapular nerve

Derived from 6th/7th cervical spinal nerves (Brachial plexus)
Innervates the subscapularis

177

Musculocutaneous nerve

Derived from 6th/7th/8th cervical spinal nerves (Brachial plexus)
Innervates coracobrachialis, biceps brachii, brachialis.
A branch off the musculocutaneous joins with the median nerve.

178

Axillary nerve

Derived from 7th/8th cervical spinal nerves (Brachial plexus)
Innervates

179

Thoracodorsal nerve

Derived from 8th cervical spinal nerve (Brachial plexus)
Innervates the latissimus dorsi

180

Radial nerve

Derived from 7th/8th cervical and 1st/2nd thoracic spinal nerves (Brachial plexus)
Innervates all the extensor muscles of the elbow, carpal, phalangeal joints, triceps, tensor fasciae antebrachii, and anconeus.
Terminates as a deep and superficial branch.

181

Median nerve

Derived from 8th cervical and 1st/2nd thoracic spinal nerves. (Brachial plexus) Common trunk with the ulnar nerve.
Receives a branch from the musculocutaneous nerve.
Innervates most of the muscles of the forearm and skin of the palmar surface of the paw -
Pronator teres
Pronator quadratus
Flexor carpi radialis
Superficial digital flexor
Parts of deep digital flexor

182

Ulnar nerve

Derived from 8th cervical and 1st/2nd thoracic spinal nerves (Brachial plexus) Common trunk with the median nerve.
Innervates the skin of the distal medial aspect of the brachium and the caudal aspect of the antebrachium -
Flexor carpi ulnaris
Parts of deep digital flexor

183

Caudal pectoral nerves

Derived from 8th cervical and 1st and 2nd thoracic spinal nerves.
Innervates the deep pectoral muscle.

184

Lateral thoracic nerve

Derived from from 8th cervical and 1st thoracic spinal nerves. (Brachial plexus)
Innervates the cutaneus trunci.

185

Cephalic vein

Begins on palmar surface of paw and runs over the cranial surface of the antebrachium.
Enters the external jugular vein near the thoracic inlet.

186

Accessory cephalic vein

Arises from small veins on the dorsum of the paw and joins the cephalic on the distal third of the antebrachium.

187

Median cubital vein

Forms connection between the cephalic and brachial veins over the flexor surface of the elbow.

188

Axillobrachial vein

Leaves the cephalic vein at the middle of the antebrachium.
Joins the axillary vein near the deltoideus.

189

Omobrachial vein

Arises from the axillobrachial vein and enters the external jugular vein cranial to the cephalic vein.

190

Median artery

Termination of the brachial artery after the branch of the common interosseous artery. Runs with the median vein.
Extends to the superficial palmar arch in the paw.
Branches:
Deep antebrachial artery
Radial artery

191

Common interosseous artery

Short branch off the brachial artery.
Branches into:
Ulnar artery
Caudal interosseous artery
Cranial interosseous artery

192

Ulnar artery

Courses caudally from the common interosseous artery and continues with the ulnar nerve.
Supplies the ulnar and humeral heads of the deep digital flexor and flexor carpi ulnaris.

193

Caudal interosseous artery

Course distally from the common interosseous artery between the radius and ulna under the pronator quadratus.
Supplies many structures around the radius and ulna with small branches then joins with radial and median arteries to supply the palmar surface of the forepaw.

194

Cranial interosseous artery

Third branch off of the common interosseous artery, difficult to visualize.

195

Superficial palmar arch

Formed by the anastomosis of the median artery and caudal interosseous artery.
Gives rise to the palmar common digital arteries that supply the palmar surface of the forepaw.

196

Radial artery

Arises from the median artery in the middle of the leg and follows medial border of the radius.

197

Deep antebrachial artery

Caudal branch of the median artery just under the common interosseous artery.
Supplies the flexor carpi radialis, deep digital flexor, flexor carpi ulnaris, and superficial digital flexor.

198

Radial nerve

Supplies the extensors of the elbow, carpus, and digital joints.
Divides into superficial and deep branches, superficial divides again to medial, lateral, and lateral cutaneous branches.

199

Deep branch of the radial nerve

Courses with the brachial into the forearm.
Innervates the extensor carpi radialis, common digital extensor, supinator, lateral digital extensor, the abductor digiti I longus, and the ulnaris lateralis.

200

Medial and lateral branches of the radial nerve

Follow the medial and lateral sides of the cephalic vein.
Innervate (sensory to) the skin on the cranial and lateral surface of the forepaw and dorsal surface of the carpus, metacarpus and digits.
Terminate in the dorsal common digital nerves.

201

Palmar branch of the ulnar nerve

Sensory to the palmar surface of the forepaw and motor to the intrinsic muscles of the forepaw.

202

Dorsal and palmar common digital vessels and nerves

Superficial nerves and vessels of the forepaw
Each common trunk divides to branches medial and lateral to each digit.

203

Dorsal and palmar metacarpal vessels and nerves

Deep nerves and vessels of the forepaw
Each common trunk divides to branches medial and lateral to each digit.

204

Cutaneous area of a nerve

Entire area of skin innervated by a nerve. May overlap with the cutaneous area of other nerves.

205

Autonomous zone of a nerve

The area of skin innervated solely by one nerve with no overlap by the adjacent nerves.

206

External pudendal artery

Emerges from the superficial inguinal ring. Courses caudally near the gracialis.

207

Caudal superficial epigastric artery

Continuation of the external pudendal artery that courses cranially over the rectus abdominus.
Supplies the prepuce, caudal abdominal mammae, inguinal mammae, labia, and scrotum.

208

Superficial inguinal lymph nodes

Drain the mammae, prepuce, scrotum, and the ventral abdominal wall as far cranially as the umbilicus

209

Cranial abdominal arteries

Arises with the caudal phrenic artery off the aorta
Perforate abdominal musculature and supply the skin.

210

What are the four main arteries that supply the abdominal wall?

Cranial abdominal artery
Cranial epigastric artery
Caudal epigastric artery
Deep circumflex iliac artery

211

Patterning of the ventral branches of the first four lumbar nerves

Run ventrocaudally from their vertebra of origin to the area of skin innervated.
(Names:
T1: Cranial iliohypogastric
T2: Caudal iliohypogastric
T3: Ilioinguinal
T4: Lateral cutaneous femoral nerves)

212

Genitofemoral nerve

Arises from the 3rd and 4th lumbar nerves
Bound to external pudendal vein
Innervates cremaster, prepuce, and skin of inguinal thigh in both sexes.

213

Spermatic fascia

Continuation of abdominal and transversus fascia
Surrounds the structures coming through the superficial inguinal ring including the vaginal tunic, spermatic cord, and cremaster muscle.

214

Vaginal process

Diverticulum of the peritoneum present in both sexes
Called the vaginal tunic in males and covers the testes, and spermatic parts.
Consists of parietal, visceral, and connecting parts.

215

Parietal vaginal tunic

Outer layer of the peritoneal diverticulum. Surrounds a portion of the peritoneal cavity between the parietal and visceral tunics. Joins with the visceral layer at the caudal end of the testis.

216

Visceral vaginal tunic

Inner layer of the peritoneal diverticulum, closely fused to the testis, epididymus, and ductus deferens. Joins with the parietal layer at the caudal end of the testis.

217

Mesorchium

Connecting mesentery of the testis that contains nerves and vessels

218

Mesoductus deferens

Fold of the peritoneum that attaches the ductus deferens to the body wall and mesorchium. Contains the artery, vein, and nerve of the ductus deferens.

219

Spermatic cord

The ductus deferens and spermatic artery and vein (everything above the testes)

220

Ductus deferens

Carries the sperm from the tail of the epididymus to the urethra.

221

Deferens artery and vein

Accompany the ductus deferens

222

Patterning of the testicular artery and vein

Veins and nerves are woven around the artery. Important for temperature control of the testes.

223

Cremaster muscle

Arises from the free border of the internal abdominal oblique and attaches to the vaginal tunic near the testes. Comes through the superficial inguinal ring.

224

Pampiniform plexus

Venous plexus of the testicular veins, interwoven with nerves and wrapped around the artery, important for temperature control of the testes.

225

Epididymus

Head: cranial, least mature sperm.
Middle
Tail: caudal, most mature sperm.

226

Ligament of the tail of the epididymus

Connects the tail of the epididymus to the vaginal process.
Forms the round ligament of the uterus in females.

227

Proper ligament of the testis

Connects the tail of the epididymus to the testis.

228

Scrotum

Skin over the testes divided by an external raphe and an internal median septum.

229

Round ligament of the uterus

Runs with the peritoneal diverticulum out of the superficial inguinal ring in the female. May
extend as far as the fascia.

230

Nerve types in the plexus of the testes

Both autonomic and sensory
sympathetic axons from the third to 5th lumbar sympathetic ganglia.

231

Inguinal canal

Short fissure filled with connective tissue, bounded by the four abdominal muscles and the superficial and deep inguinal rings. Vaginal tunic/process and spermatic cord/round ligament of the uterus travel through this canal.

232

Abdominal cavity

Formed by the muscles of the abdominal wall, ribs, and the diaphragm. Lined by the peritoneum. Contains all of the abdominal organs.

233

Peritoneal cavity

Closed space lined by a serous membrane, between the parietal and visceral peritoneum. No organs within the cavity.
Derived from somatic and splanchnic mesodermal layers of the embryonic coelom.

234

Parietal peritoneum

Lines the body cavity of the abdomen and scrotum.

235

Visceral peritoneum

Lines the organs of the abdominal cavity and scrotum.

236

Connecting peritoneum

Double sheet of peritoneum that extends between the parietal and visceral peritoneums. Forms the mesentery that suspends the organs, as well as containing their nerves and vessels.
Its folds can form the mesenteries, omenta, or ligaments of the abdominal cavity.

237

Transversalis fascia

Reinforces the parietal peritoneum and attaches it to the abdominal muscles and diaphragm.

238

Falciform ligament

Fold of peritoneum that passes from the umbilicus to the diaphragm.
Connects to the liver between the medial and quadrate lobes.
Accumulation of fat inside this ligament in adults.
Umbilical vein ran through this - may find remnants of the embryonic ventral mesentery here in young animals.

239

Round ligament of the liver

Attached to the free border of the falciform ligament, more prominent in young animals.

240

Median ligament of the bladder

Caudal to the umbilicus, fold of the peritoneum running caudally to the urinary bladder. Umbilical artery and urachus ran through this structure.

241

Vaginal ring

Opening in the parietal peritoneum as it leaves the abdomen and enters the inguinal canal. Contains the spermatic cord and vaginal tunic/process.

242

Deep inguinal ring

Fatty structure formed by the folds of the transversalis fascia and associated adipose tissue on the superficial side of the vaginal ring.

243

Caudal epigastric artery

Course cranially on the deep face of the caudal part of the rectus abdominis.
Origin from the pudendoepigastric trunk.

244

Greater omentum

Also called the epiploon
Extension of the connecting peritoneum, with two layers.
Extends caudoventrally to many of the abdominal organs. (outside of the liver)

245

Superficial leaf of the greater omentum

Lacelike. Layer closer to the peritoneum. Encloses the spleen.

246

Deep leaf of the greater omentum

Layer closer to the viscera. Encloses the left lobe of the pancreas.

247

Omental bursa

Space between the deep and superficial leaf of the greater omentums.
Can cause colic in horses if a loop of intestine becomes entrapped in this sac. May occasionally happen in the small animal but rare (epiploic entrapment).

248

Urinary bladder

Empty: lies on the floor of the abdomen.
Full: Displaces freely moving viscera, frequently reaching a transverse plane through the umbilicus.

249

Uterus

Short cevix
Two long horns.

250

How does the uterus change shape during pregnancy?

Lies on the floor of the abdomen.
As pregnancy develops, middle parts of the horns move ventrocranially, causing the uterus to bend on itself.

251

Round ligament of the uterus

May pass through the inguinal canal.
Fold of the peritoneum from the mesometrium which surrounds the uterus.
Remnant of fetal gubernaculum.
Becomes the ligament of the tail of the epididymus in males.

252

Spleen

Left side of the abdomen
Shape variable (HUGE in our dogs as a result of the barbiturates they were given).

253

Gastrosplenic ligament

The part of the greater omentum that attaches to the spleen.

254

Muscular parts of the diaphragm plus their attachments?

Tendinous center: V shaped and small, in the center of the diaphragm, runs between the costal and lumbar parts on each side.
Lumbar part: Left and right crura: attach to the bodies of L3 and L4 by large tendons.
Costal part: Arises from the medial surface of ribs 8-13, interdigitating with the transversus abdominis.
Sternal part: Narrow, from sternum to xyphoid cartilage.

255

Cupula of the diaphragm

Most cranial part of the diaphragm, bulges into the thorax.

256

Where does the aorta pass through the diaphragm?

Aortic hiatus. Dorsal diaphragm.

257

Where does the caudal vena cava pass through the diaphragm?

Caval foramen.

258

Where does the esophagus pass through the diaphragm?

Esophageal hiatus. Right crus of the diaphragm.

259

Where does the thoracic duct pass through the diaphragm?

Aortic hiatus. Dorsal diaphragm.

260

Where does the azygous vein pass through the diaphragm?

Aortic hiatus. Dorsal diaphragm.

261

Liver (lobes)

1. Caudate lobe
2. Right lateral lobe
3. Right medial lobe
Gallbladder!
4. Quadrate lobe
5. Left medial lobe
6. Left lateral lobe

262

What are the two sides of the liver?

Visceral surface (caudal) and parietal surface (cranial).

263

Which lobe of the liver does the right kidney contact?

Caudate lobe, forming the renal impression on the caudate process.

264

Which lobe of the liver does the lesser curvature of the stomach contact?

Caudate lobe, contacting the papillary process of the caudate lobe.

265

Lesser omentum

The omentum that is hidden under the liver and viscera rather than padding the ventral side of the viscera.

266

Hepatoduodenal ligament

Right free edge of the lesser omentum, attaching the liver to the duodenum.
Contains the portal vein, hepatic artery, and the bile duct.

267

Epiploic foramen

Formed by the omenta. Opens in the main peritoneal cavity.

268

Mesoduodenum

Originates at the dorsal abdominal wall and root of the mesentery and attaches to the duodenum. Continuous with the mesentery of the jejunum.

269

Duodenocolic fold

Attachment of the ascending duodenum to the mesocolon of the descending colon.

270

Mesentery

Passageway for nerves and vessels to supply the small intestines. Continuous with the mesocolon of the ascending colon.

271

Root of the mesentary

Attachment of the mesentery to the abdominal wall at the second lumbar vertebra.

272

Mesocolon (parts and function)

Ascending, transverse, and descending parts.

273

Right and left triangular ligaments

Extend from the right and left crus of the diaphragm to the right and left lateral lobes of the liver.

274

Coronary ligament

Sheet of peritoneum continuous with both the right and left triangular ligaments on the dorsal side.

275

Hepatic ducts

Carries bile from microscopic structures out of the liver from each lobe. Joins with the cystic duct to form the bile duct.
Variable arrangements.

276

Gallbladder

Between the quadrate and right medial lobes of the liver
Storage for bile
Neck is continuous with the cystic duct.

277

Cystic Duct

Carries bile to and from the gallbladder.
Joins with the hepatic ducts to form the bile duct.

278

Bile duct

Ductus choldochus
Created by the joining of the hepatic and cystic ducts
No valves = flow in two directions
Empties into the duodenum at the major duodenal papilla.

279

Major duodenal papilla

Termination of the bile duct and the pancreatic duct.
Most cranial papilla in the descending duodenum.

280

Parts of the Stomach

1. Cardiac part (near esophagus)
2. Fundus (left side)
3. Body (middle)
4. Pyloric part (right side)

281

Parts of the pylorus

1. Pyloric antrum (initial and thin walled)
2. Pyloric canal (narrower and thicker)
3. Pylorus (sphincter)

282

Lesser curvature of the stomach

Faces mainly to the right

283

Greater curvature of the stomach

Faces mainly to the left

284

How does the position of the empty stomach differ from that of the full stomach?

Empty stomach: Hidden under the liver, strongly curved around the papillary process of the liver.
Full stomach: In contact with the ventral abdominal wall, displacing the intestinal mass.

285

Duodenum and its parts.

Most fixed part of the small intestine, suspended by mesoduodenum.
1. Cranial duodenal flexure near the pylorus
2. Descending part
3. Caudal duodenal flexure
4. Ascending part.

286

Where does the duodenum turn into the jejunum?

Duodenojejunal flexure
At the root of the mesentary

287

Jejunum

The coils of the small intestine, supplied by the cranial mesenteric artery.
Root of the mesentery attaches the jejunum to the dorsal body wall.

288

Mesenteric lymph nodes

Near the vessels in the mesentery.

289

Ileum

Continuous with the jejunum, recognized by the anti mesenteric iliac artery.

290

Ileocolic orifice

Junction between the ileum and the colon. Sphincter.

291

Cecum

S-shaped blind tube off of the colon.
Lies to the right of the colon.

292

Cecocolic orifice

Junction between the cecum and the colon.

293

Parts of the colon

1. Ascending colon
2. Right colic flexure
3. Transverse colon
4. Left colic flexure
5. Descending colon

294

Rectum

Continuous with the descending colon

295

Parts of the pancreas

Body: at the pylorus
Left lobe: between the peritoneal layers that form the deep leaf of the greater omentum.
Right lobe: dorsomedial to the descending duodenum.

296

Pancreatic duct

Terminates in the descending duodenum with the bile duct at the major duodenal papilla

297

Accessory pancreatic duct

Terminates in the descending duodenum at the minor duodenal papilla (caudal to the major papilla).
Major pancreatic duct in the dog.

298

Adrenal glands

Light cortex and dark medulla
Crossed by the common trunk of the caudal phrenic and cranial abdominal veins.

299

What are the locations of the two kidneys?

Right kidney: L1-L3 (cranial)
Left kidney: L2-L4 (caudal)

300

What are the kidneys considered to be?

Retroperitoneal organs.

301

What passes through the hilus of the kidney?

Renal vessels and nerves and the ureter.

302

Renal pelvis

Expansion of the ureter to collect urine.

303

Renal sinus

Fat filled space that surrounds the renal pelvis and contains the renal vessels.

304

Renal cortex

Light, granular region on the periphery of the kidneys. Contains renal corpuscles and tubules.

305

Renal medulla

Darker, striated central portion of the kidneys that contains collecting ducts.

306

Arcuate branches

Branches of the renal vessels that appear at the corticomedullary junction

307

Renal crest

Ridge of the medulla projecting into the renal pelvis. Collecting tubules of the medulla end here.

308

Renal pyramids

Formed by the medulla and the intersections of the pelvic recesses.

309

Pelvic recesses

Projections of the renal pelvis outwards between the renal pyramids.

310

Where are the ovaries located?

Near the caudal poles of the kidneys.

311

Ovarian bursa

Thin walled peritoneal sac that encloses the ovary.
Slitlike orifice on the medial surface opens to the peritoneal cavity.
Formed by the mesovarium and the mesosalpinx.

312

Uterine tube

Oviduct. Runs through the lateral wall of the bursa from the ovary to the uterine horn.

313

Infundibulum

Dilated ovarian end of the uterine tube.
Fimbriated margin to catch eggs as they leave the ovary
Many fimbriae project through the orifice of the bursa into the peritoneum.

314

Abdominal ostium

The entrance of the infundibulum into the uterus, where fertilization takes place.

315

Tubouterine junction

Junction between the uterine horn and uterine tube.
Here the transit of sperm and ova are regulated.

316

Broad ligaments of the uterus

Peritoneal folds that attach the uterus to the lateral sublumbar region.
Three parts: mesometrium, mesovarium, and mesosalpinx.

317

Mesometrium

Attaches to cranial end of the vagina, uterine cervix, uterine body, and uterine horn.

318

Uterine horn

Long part of the uterus from the uterine body and cervix to the uterine tube.

319

Mesovarium

Cranial portion of the broad ligament and helps to create the ovarian bursa.

320

Mesosalpinx

Helps create the ovarian bursa and attaches the uterine tube to the mesovarium.

321

Suspensory ligament of the ovary

Holds the ovary in a relatively fixed position by connecting with the transversalis fascia.

322

Proper ligament of the ovary

Attaches the ovary to the cranial end of the uterine horn

323

Round ligament of the uterus

The free border of the mesometrium.
Homologue to the embryonic gubernaculum, which becomes the ligament of the tail of the epididymus in the male. Passes through the inguinal canal.

324

Patterning of the vagus nerve

Travels through the neck in the vagosympathetic trunk (GVE, GVA)
Separates from the sympathetic trunk at the thoracic inlet
RLNs branch off
Branches into dorsal vagal trunk and ventral vagal trunk caudal to the heart
Passes through the esophageal hiatus
Gives off a celiac branch

325

What do the dorsal and ventral branches of the vagus innervate?

The esophagus

326

Where does cranial nerve ten pass through the diaphragm

Vagus nerve; through esophageal hiatus

327

Dorsal vagal trunk

Uniting of the right and left dorsal vagal branches near the diaphragm

328

Ventral vagal trunk

Uniting of the right and left ventral vagal branches caudal to the root of the lung

329

What does the dorsal vagal trunk innervate in the abdomen?

Lesser curvature of the stomach, pylorus, small intestines, and adrenal glands.

330

What does the ventral vagal trunk innervate in the abdomen?

Liver, parietal surface of the stomach, and the pylorus.

331

Psoas minor

Cranial to the psoas major, running along the lumbar vertebrae within the abdomen.
Attachments: Fascia of the quadratus lumborum to T13 and L1-5, inserts on the arcuate line of the ilium.

332

What type of nerves are the splanchnic nerves? What are the types of splanchic nerves?

GVE sympathetics.
Branch off of the sympathetic trunk.
Major = First branch off at T12/13
Minor = before the adrenals
Lumbar = after the adrenals

333

What does the major splanchnic nerve run towards?

Courses to celiacomesenteric ganglia and plexus.

334

What do the minor splanchnic nerves innervate?

Adrenal glands.
Terminates in celiacomesenteric ganglia and plexus.

335

How are the lumbar splanchnic nerves distributed?

To aorticorenal, cranial mesentaric, and caudal mesenteric ganglia and plexuses.

336

What does the celiacomesenteric ganglion and plexus consist of?

Celiac ganglia
Cranial mesenteric ganglion
Terminal plexus of celiac artery

337

What do the nerves of the caudal mesenteric ganglion innervate?

A portion of the colon

338

Right and left hypogastric nerves

Leave the caudal mesenteric ganglion and run caudally near the ureters, then enter the pelvic canal.

339

Lumbar arteries

Paired
Penetrated the dura and arachnoid to join with the ventral spinal artery and supply the spinal cord
Also supply muscles and skin above lumbar vertebrae.

340

Celiac artery

From the aorta between the diaphragmatic crura.
Three branches: hepatic, left gastric, and splenic.
Often covered by the celiac plexus.

341

Hepatic artery

First branch off the celiac, directed cranially towards the liver.
Branches into the hepatic branches (1-5), cystic artery, right gastric artery, and gastroduodenal artery.

342

Hepatic branches

Leave the hepatic artery
Supply the liver
One to five branches

343

Cystic artery

Leaves hepatic artery
Supplies the gallbladder

344

Right gastric artery

Leaves the hepatic artery.
Small artery that passes dorsal to the stomach and then supplies the lesser curvature of the stomach.
Anastomoses with the left gastric artery.

345

Gastroduodenal artery

Leaves the hepatic artery.
Supplies the pylorus.
Terminates with right gastroepiploic artery.

346

Right gastroepiploic artery

Terminal branch of the gastroduodenal artery.
Anastomoses with the left gastroepiploic artery and supplies the greater curvature of the stomach.

347

Cranial pancreaticoduodenal artery

Terminal branch of the gastroduodenal artery, follows the descending duodenum.
Supplies the duodenum and right lobe of the pancreas.
Anastomoses with the caudal pacreaticoduodenal artery.

348

Left gastric artery

Branch off of the celiac artery
Runs to the lesser curvature of the stomach and supplies both sides of the stomach.
Anastamoses with the right gastric artery near the pylorus.

349

Splenic artery

Branch off of the celiac artery
Crosses and supplies the left lobe of the pancreas
Enters the hilus of the spleen
Gives rise to the short gastric arteries and left gastroepiploic artery.

350

Short gastric arteries

Branches of the splenic artery
Supply the greater curvarture of the left side of the stomach.

351

Left gastroepiploic artery

Branch of the splenic artery.
Supplies the greater curvature of the stomach.
Anastomoses with the right gastroepiploic artery.

352

Cranial mesenteric artery

Unpaired, leaves the abdominal aorta just caudal to the celiac branch.
Branches into the common trunk of the middle and right colic arteries, the ileocolic artery, the caudal pancreaticoduodenal artery, the jejunal arteries, then terminates in the branches of the ileal arteries.

353

Middle colic artery

Arises from a common trunk with the right colic artery off the cranial mesenteric.
One branch supplies the descending colon and anastamoses with the left colic artery.
Other branch supplies the left colic flexure and transverse colon and anastomoses with the right colic artery.

354

Right colic artery

Arises from a common trunk with the middle colic artery off the cranial mesenteric.
Supplies the ascending colon, right colic flexure, and the transverse colon (anastomosing with the middle colic artery and colic branch of the ileocolic artery)

355

Ileocolic artery

Branch off of the cranial mesenteric artery.
Branches into the colic branch and the cecal artery, then continues as the mesenteric ileal branch.

356

Colic branch of the ileocolic artery

Supplies the ascending colon, anastomoses with the right colic artery.

357

Cecal artery

Branch off of the ileocolic artery.
Supplies the cecum
Then terminates as the antimesenteric ileal artery supplying the ileum.

358

Mesenteric ileal branch of the ileocolic artery

Termination of the ileocolic branch.
Supplies the ileum.
Anastomoses with the ileal arteries.

359

Caudal pancreaticoduodenal artery

Branch of the cranial mesenteric artery.
Supplies descending duodenum and right lobe of the pancreas.
Anastamoses with the cranial pancreaticoduodenal artery.

360

Jejunal arteries

Branches of the cranial mesenteric artery.
Form cascades in the mesentery and supply the jejunum.

361

Ileal arteries

Termination of the cranial mesenteric artery.
Supply the ileum, run through the mesentery.
Last branch anastamoses with the ileocolic artery.

362

Common trunk of the caudal phrenic and cranial abdominal arteries

Paired, arise from the abdominal aorta caudal to the cranial mesenteric and cranial to the renal arteries.

363

Caudal phrenic artery

Runs cranially to supply the diaphragm.

364

Cranial abdominal artery

Runs into the abdominal wall through the internal abdominal obliques, can be seen superficially.

365

Renal arteries

Paired, leave the aorta at different levels (right cranial to the left)
Right is longer than the left.
Supply the kidneys.

366

Ovarian arteries

Homologous to the testicular arteries.
Paired, caudal to the renal arteries.
Varies in size, position, and tortuosity depending on the size and the development of the uterus.
Supplies the ovary, ovarian bursa, uterine tube, and uterine horn.
Anastomoses with the uterine artery.

367

Testicular arteries

Homologous to the ovarian arteries.
Also paired, caudal to the renal artery.
Crosses the ventral surface of the ureter.
Lies in the mesorchium with the vein and nerve plexus, then through the vaginal ring.

368

Caudal mesenteric artery

Unpaired, arises from the abdominal aorta near its termination as the iliac arteries.
Runs in descending mesoduodenum and branches to the left colic artery and cranial rectal artery.

369

Left colic artery

Supplies the left colic flexure and anastomoses with the middle colic artery.

370

Cranial rectal artery

Descends along rectum and supplies.
Anastamoses with the middle rectal artery.

371

Deep circumflex iliac artery

Paired, arises from the abdominal aorta near the external iliac.
Crosses the psoas minor, perforates abdominal wall and supplies skin of the caudal abdomen, flank, and cranial thigh.

372

Portal vein

Returns blood from the GI tract to the liver and then to the caudal vena cava
Gastroduodenal vein: drains pancreas, stomach, duodenum, and greater omentum
Splenic vein: Drains lesser curvature of the stomach, spleen, pancreas, and greater omentum
Cranial and caudal mesenteric veins: drain the small intestine
Separates into a right and left branch as it enters the liver, to right and left three lobes each.

373

Levator ani muscles

Broad thin muscle lying dorsal to the internal obturator on the wing of the ileum.
Attachments: Medial edge of the body of the ileum and caudal vertebrae 3-7.

374

Coccygeus muscle

Lateral to the levator ani - can be seen on the medial surface of the leg next to the internal obturator.
Attachments: ischiatic spine and transverse processes of caudal verterbrae 2-4.

375

Pelvic diaphragm

Formed by the coccygeus and levator ani muscles.
Contract with the abdominal muscles to keep the viscera from moving into the pelvic canal.
In older dogs can become weak and may see perianal hernias.

376

Pelvic plexus

Lies near the colon, dorsal to the prostate, and near the vaginal/prostatic artery.
Joining of the hypogastric nerve (sympathetic) and pelvic nerve (parasympathetic).

377

Pelvic nerve

Parasympathetic preganglionic axons.
Very small, runs from the bladder to the pelvic plexus
Supplies: urogenital organs, rectum, descending colon.

378

Pararectal fossa

Extension of the peritoneal cavity dorsal to the rectum on either side of the mesorectum.
Extends to second caudal vertebra.

379

Rectogenital pouch

Continuous with pararectal fossa, ventral to this. Communicates with the uterus in the female.

380

Vesicogenital pouch

In the female, the pouch between the uterus and the bladder.

381

Iliac artery patterning

External iliac becomes the femoral artery.
Internal iliac branches into the caudal gluteal artery and internal pudendal artery. Also gives off the round ligament of the bladder, the remnant of the umbilical artery.
Small unpaired median sacral artery between the internal iliac.

382

Vascular lacuna

Where the external iliac exits the abdominal cavity and becomes the femoral artery.

383

Pubovesical pouch

Communication of the rectogenital (male) or vesicogenital (female) pouch between the bladder and the ventral body wall and pubis. Divided by the median ligament of the bladder.

384

Caudal gluteal artery

Branch of the internal iliac artery.
Supplies the muscles on the outside of the pelvis and the caudal thigh.

385

Internal pudendal artery

Branch of the internal iliac artery.
Vaginal/prostatic artery branches off here.
Supplies the pelvic viscera and external genitalia at the ischial arch.

386

Vaginal/prostatic artery

Branch off of the internal pudendal artery.
Termination = uterine artery or artery of the ductus deferens.

387

Uterine artery

Supplies the uterus, and branches into a caudal vesical artery and middle rectal artery.

388

Caudal vesical artery

Branch off of the uterine or artery of the ductus deferens.
Supplies bladder, urethra (both sexes)
Female - also runs in round ligament of the uterus to supply the uterine body and horn, anastomoses with the uterine branch of the ovarian artery.

389

Middle rectal artery

Branch off of the uterine or the artery of the ductus deferens.
Female: supplies rectum and vagina.
Male: supplies rectum, prostate, and urethra.

390

Artery of the ductus deferens

Branch off the prostatic artery.
Gives off caudal vesicle and middle rectal arteries.
Supplies the ductus deferens.

391

Ventral perineal artery

Termination of the internal pudendal artery after it passes the ischiatic notch with a variable urethral artery and artery of the penis/clitoris.
Branch here for the caudal rectal artery to the rectum and anus.

392

Artery of the penis

Terminates as three branches at the ischial arch:
Artery of the bulb of the penis
Deep artery of the penis
Dorsal artery of the penis
Surrounded by veins that will assist with erection.

393

Artery of the bulb of the penis

Arborizes in the bulb of the penis
Supplies corpus spongiosum and penile urethra.

394

Deep artery of the penis

Enters the corpus cavernous at the crus.

395

Dorsal artery of the penis

Supplies the prepuce and pars long glandis.

396

Artery of the clitoris

Supplies clitoris and vestibular bulb.

397

Cranial vesical arteries

Remnant artery of the umbilical artery that has not closed all the way to the round ligament of the bladder. Supply bladder.

398

Parts of the urinary bladder

Apex
Body
Neck: no gross sphincter but smooth muscle innervation makes a physiological sphincter

399

Lateral ligament of the bladder

Attaches the bladder to the pelvic wall, often contains adipose tissue.

400

Urethral muscle

Serves as a voluntary sphincter for the urethra
In the pelvic canal and surrounds the urethra.
Innervated by the pudendal nerve

401

Trigone of the bladder

Triangle formed by the urethra and the entrance of the ureters into the bladder.

402

What are the infoldings of the empty bladder called?

Rugae

403

Where is the rectum

Within the pelvic canal. Continuous with the colon and the anal canal.

404

Three zones of the anal canal

Columnar zone: (Mucosa forms longitudinal ridges/anal columns)
Cutaneous zone: Fine hairs, cirucumanal glands, and paranal sinus).
Anus: After the external sphincter muscle.

405

Paranal sinus

Anal sac
Opens into the cutaneous zone of the anal canal.

406

Where is the external sphincter muscle and what kind of muscle does it contain? What supplies the external sphincter muscle?

Surrounds the anal sac external to the cutaneous zone of the anal canal
Striated muscle
Innervated by the caudal rectal branch of the pudendal nerve
Supplied by the caudal rectal branch of the pudendal artery. `

407

Where is the internal sphincter muscle and what kind of muscle does it contain?

Enlargement of the smooth muscle coat of the anal canal near the anus.

408

Rectococcygeus muscle

Lies between the levator ani and the coccygeus to connect the anus with the tail
Attachments: dorsal surface of the rectum and sphincter muscles to caudal vertebrae.

409

Prostate gland (male)

Surrounds the neck of the bladder, varies in size.
Thick capsule that is partially divided into right and left lobes by a septum.

410

Uretral parts (male)

Pelvic part
Penile part
Based on location

411

Colliculus seminalis (male)

Hillock into the lumen of the urethra where the ductus deferens opens.

412

Parts of the penis (male)

Root (crura and bulb)
Body (fibrous region that "locks" by bending).
Glans (pars longa glandis and bulbis glandis)

413

Preputial orifice (male)

Opening of the prepuce
Haired region and smooth region of the prepuce meet here.

414

Fornix (male)

Deepest recess of the prepuce, pocketlike. Eliminated in erection.

415

Urethral crest (male)

Widening of the prostate into the pelvic urethra.

416

What are the crura of the root of the penis formed by? (male)

Corpus cavernosum penis
Vascular cavernous tissue
Extends from the ischiatic tuberosities on each side.

417

What is the corpus cavernosum penis supplied by? (male)

Deep artery of the penis

418

Tunica albuginea (male)

Thick fibrous white tunic surrounding the corpus cavernosum.

419

Ischiocavernosus muscle (male)

Arises from the ischiatic tuberosity and covers the origin of the crus, then inserts on the crus.

420

Retractor penis muscle (male)

Very long and skinny cordlike muscle. Mix of smooth and striated muscle.
Attachments: ventral surface of the sacrum, first 2-3 caudal vertebrae, and anal sphincters to the glans of the penis.

421

Bulbospongiosus muscle (male)

Bulges between the ischiocavernosus and covers the bulb of the penis.

422

Bulb of the penis (male)

Dorsal expansion of the corpus spongiosum.
Part of the root of the penis between the left and right crura and covered by the bubospongiosus m.

423

Corpus spongiousum (male)

Surrounds the urethra over its entire length.
Supplied by the artery of the bulb of the penis.

424

Ischiourethralis muscle (male)

Transverse muscle from ischial tuberosity to pelvic symphysis. Encircles the left and right dorsal veins of the penis, helping maintain erection.

425

Bulbis glandis (male)

Expansive vascular structure that surrounds the proximal end of the os penis
Helps retain the penis in the vagina during copulation.
Separated from the pars longa glandis by connective tissue.

426

Pars longa glandis (male)

Overlaps with the bulbis glands and continues to the distal end. Separated from the bulbis glands by connective tissue.

427

Os penis (male)

Forms about 1mo after birth from ossification of corpora cavernosa.
Ends in a pointed cartilagenous tip dorsal to urethral opening.

428

Deep V in the center of the os penis is called?
Which surface is it on?
(male)

The urethral groove
Surrounds the urethra and corpus spongiosum on 3 sides.
Ventral surface

429

Cervix (female)

Constricted caudal portion of the uterus. Small palpable enlargement grossly.

430

Cervical canal (female)

Vertical opening through the cervix.

431

Vagina (female)

Between the cervix and the vestibule. Mucosal lining has transverse folds so that it can expand.

432

Fornix (female)

s

433

Vestibule (female reproductive tract)

Continuous between the vagina and the vulva.
Contains the vestibular bulbs, fossa clitoris, and the urethral tubercle.

434

Urethral tubercle (female)

Projection of tissue where the vagina and urethra meet the wall of the vestibule.
Dorsal to the vulva.
Contains the external urethral orifice.

435

Vestibular bulbs (female)

Erectile tissue homologous to the bulb of the penis. Small and close to the clitoris in the vestibular walls.

436

Clitoris (female)

Female homologue of the penis. Located in the floor of the vestibule.

437

Glans clitoridis (female)

Two crura attached and a glans body. Very small erectile structure in the fossa clitoridis . May contain an os clitoridis.

438

Fossa clitoridis (female)

Contains the glans clitoridis, in the floor of the vestibule.
Do not mistake with the urethral opening (which is cranial and ventral farther into the vestibule).

439

Vulva parts (female)

Two labia that are joined by dorsal and ventral commissures.

440

Rima pudendi

Orifice formed by the parts of the vulva.

441

Neurons are? Axons are?

Excitable cells that are the functional unit of a nerve. Their axons move signals from one part of the body to another.

442

What are the layers of the meninges?

(Epidural/extradural space)
The Dura mater
(Subdural space - more spread out).
The Arachnoid mater
(subarachnoid space)
The Pia mater

443

Cerebral spinal fluid cisterns

Cerebellomedullay (can access at the atlantoccipital joint).
Lumbosacral (can access at the end of L7).

444

What are the functions of cerebral spinal fluid?

Protect the central nervous system
Provide nutrients
Provide a sink for electrons
Provide buoyancy so the CNS weighs very little.

445

Brain epidural space

A potential space - not there unless something is wrong such as a hematoma. Its presence increases inter cranial pressure.

446

Spinal nerve formula for the dog?

C8 T13 L7 S3 Cd5 (36 pairs)

447

Caudal Equina

The combination of nerves L6-Cd5 that branch off of L5/6/7 (spp. dependent) like a horse's tail.

448

Autonomic nervous system.

Synonym for visceral nervous system.

449

How do you test a reflex arc? What is going on in the nerves?

Often with skin pinching. Should see the cutaneus trunci twitch. This is from the afferent neuron communicating via a spinal cord interneuron in the spinal cord before the signal is sent to the brain.

450

How are the spinal nerves numbered in relation to vertebrae?

Cervical - for the vertebrae caudal to the nerve
Thoracic and beyond - for the vertebrae cranial to the nerve.
Nerve segments of the spinal cord starts to not match vertebrae at the lumbar portion.

451

Why can we breathe without thinking about it?

Strong reflex arcs of the diaphragm
Will cause us to pass out before we can suffocate ourselves.

452

What are some examples of SSAs?

Balance, Vision, Hearing

453

What are some examples of SVAs?

Taste, Olfaction

454

Cortical input

Conscious control

455

What do GVAs sense?

The internal environment mainly.
Chemical and physical status (temp, pressure, stretch, pH)

456

What do GSAs sense?

The external environment mainly.
Pressure temp and pain from bones, skin and CT.

457

Name some physiological responses to a sympathetic signal.

Increased:
HR, RR, airway diameter, urination
Decreased:
Pupil size (mydriasis), GI output and movement
Varied:
vascular smooth muscle depending on location

458

Name some physiological responses to a parasympathetic signal.

Decreased:
HR, RR, airway diameter, urination
Increased
Pupil size (miosis), GI output and motility.

459

What types of tissue only have connections to one type of GVE? What type?

Vascular smooth muscle
Piloerector muscles
Sweat glands
Have only sympathetic innervation. Other tissues normally always in flux state between the two.

460

What tissue within the heart carries electrical impulses from Purkinje fibers?

Trabeculae carnae.

461

"Right sided" circulation

Pulmonary, low pressure

462

"Left sided" circulation

Systematic, high pressure

463

What is the general venous return pathway for blood from:
1. The head
2. The front limbs
3. Back/dorsum
4. GI system
5. Hind limbs and kidneys

1. External jugular to cranial v.c.
2. Cephalic vein to cranial v.c.
3. Azygous to cranial v.c.
4. Hepatic portal system to caudal v.c.
5. Caudal v.c.

464

Ductus venosum

Normal fetal shunt for the umbilical artery through the liver.

465

What is the point of the FO and PDA?

To improve efficiency so that the fetal circulation does not have to go through the useless underdeveloped lungs.

466

S1 occurs in which phase of the cardiac cycle? What is it caused by?

Diastole
Closure of the aortic and pulmonary valves.

467

S2 occurs in which phase of the cardiac cycle? What is it caused by?

Systole
Closure of the atrioventricular valves

468

What are the stages of the cardiac cycle (5)?

1. Atria contract (top off ventricles)
2. Ventricles contract and pressure increases, AV valves close, Pul/Aortic valves open, and blood is ejected.
(1 and 2 are systole, shorter)
3. Ejection slows and ventricles relax.
4. Aor/Pul valves close and AV valves open as pressure of ventricles drops
5. Atria and ventricles fill (at the same time).
(3,4,and 5 are diastole, longer)

469

In which phase is the heart relaxed?

Diastole

470

What produces heart sounds?

Vibrations from the sudden increase in pressure on inelastic valvular tissue.

471

Puncta maxima localization scheme

P: Pulmonary valve, on the left 3rd intercostal space
A/M: Aortic/mitral valve, on left 4th intercostal space.
R: Right AV, on R 5th intercostal space.
L: Left AV on L 5th intercostal space.

472

Basal/Apical localization scheme

Combine P/A (basal) and R/L (apical)

473

Which heart sound can split? Why?

S2 in very athletic animals.

474

What would cause a murmur?

Turbulent blood flow due to stenosis or valvular insufficiency.

475

In what area can normal lung sounds be heard?

Around the large airways
Abnormal to hear sounds in smaller airways.

476

Which GVE has more broad coverage of the body?

The parasympathetic - into the brainstem as well.

477

How can you estimate the age of the animal from a thoracic radiograph?

Radiodensity of the thymus
Older animals have radiolucent (fattier) thymuses

478

What type of nerves is the brachial plexus primarily?

GSE and GSA
Some GVE for blood supply

479

What vessels supply the extensors of the antebrachium primarily?

Axillary and radial

480

What vessels supply the flexors of the antebrachium primarily?

Median and ulnar

481

What are the major sources of blood to the forepaw?

Median artery and caudal interosseous (radial branch).

482

Collateral circulation

If one blood supply is cut off the other can make up for it.

483

Is an open or closed castration technique preferred for small animals?

Open.
Peritoneal cavity is open but technique is aseptic so this is okay.

484

Vaginal cavity

Continuous with the peritoneal cavity. Around the testes.

485

Blood supply to the abdominal wall

Dorsal: Cranial abdominal artery and Deep circumflex iliac artery
Ventral: Cranial epigastric artery and caudal epigastric artery (and their superficial branches)

486

What does the diaphragm look like when the dog is in right lateral recumbency?

The right crus is pushed cranial to the left crus.

487

What is the main muscle of inspiration?

The diaphragm
(others = muscles that pull the ribs laterally and cranially - external intercostals, serratis doornails, scalenus).

488

What is the main muscle of expiration

None - mainly the passive elastic recoil of the lungs and chest wall. Additional muscles recruited only with exertion.

489

Heave line

Mainly seen in horses.
Hypertrophy of the external abdominal obliques because of chronic effort to exhale due to an emphysema like condition caused by allergens.

490

How far does the abdominal cavity extend into the thorax via the cupula?

13th - 8th rib normally.

491

Name five structures on the left side of the abdomen?

Liver (both sides)
L kidney
Stomach
Spleen
Descending colon

492

Name five structures on the right side of the abdomen?

Liver (both sides)
R kidney
Descending duodenum
Cecum
Ascending colon

493

Name three structures in the dorsal abdomen?

Root of the mesentery
Transverse colon
Urinary bladder

494

What is found in the ventral abdomen?

The omentum
Spleen if enormously enlarged.

495

Functions of the omentum

Pads the organs
With damage forms adhesions with muscles to wall off areas of inflammation.

496

What is a sign of obesity in an abdominal radiograph?

A very clear falciform ligament in the ventral abdomen.

497

Where are the kidneys seen radiographically?

R kidney: L1-L3 (can only see the caudal pole in most radiographs)
L kidney: L2-L4

498

Name the unpaired arteries of the abdomen

Celiac
Cranial mesenteric
Caudal mesenteric
All supply the GI tract primarily

499

Why are splenectomies so time consuming?

Major branches of the splenic artery continue to the stomach and pancreas. Must ligate only the very small arteries next to the capsule of the spleen to avoid cutting off blood supply to those organs.