-R: cranial, middle, caudal, and accessory lobes

-L: cranial and caudal lobes

-trachea bifurcates into left and right principal bronchi

**on left of animal from esophagus

-contain red latex

-usually a single vein from each lobe that drains directly into the left atrium of the heart

**contains oxygenated blood

-pulmonary trunk supplies each lung with a pulmonary artery

-left pulmonary a (at root of lung) usually lies cranially to the left principal bronchus

-right pulmonary a is ventral to the right principal bronchus

-located at the burfircation of the tracha and also farther out on the bronchi

-FIND FIELD

-Aortic

-Esophageal

-Caudal Vena Cava

-Azygos Vein

-Costal

-on the right lung at the fourth and fifth intercostal spaces

-the apex of the notch is continuous with the fissure between cranial and middle lobes

-formed by the union of the right and left brachiocephalic veins at the thoracic inlet

-drains into the right atrium

-usually the last branch entering the cranial vena cava is the right azygos veins

-originates in the abdomen; collects all the dorsal intercostal veins on each side as far as cranially as the third or fourth intercostal space

ONLY RIGHT IN THE DOG

-the chief channel for the return of lymph from the lymphatics to the venous system

-begins in sublumbar region b/n crura of diaphragm, runs cranially on right dorsal border of thoracic aorta/ventral border of thoracic aorta/ventral border of the azygos vein to T6, continues cranioventrally through cranial mediastinum to left brachiocephalic veins

-also receives lymph drainage from the left TL and left tracheal trunk

-large, unpaired vessel that emerges from the left ventricle medial to the pulmonary trunk

-covered by pericardium

-right and left corony arteries are branches of this and supply the heart muscle

-first branch from the aortic arch, passing obliquely to the righ across the ventral surface of the trachea

-gives rise to left common carotid artery and terminates as the righ common carotid artery and right subclavian artery

-Left: originates from aortic arch beyond the level of the brachiocephalic trunk and passes obliquely to the left across the ventral surface of the esophagus

-Right: has 4 branches that arise medial to the first rib or intercostal space

>terminates by entering vertebral canal through the lateral vertebral foramen and contributes to the ventral spinal and basilar arteries

-supplies muscular branches to the cervical muscles and spinal branches at each intervertebral foramen to the spinal cord and its coverings

-arises distal to the vertebrala artery, crosses its lateral side, and extends dorsally as far as the vertebral end of the first rib

-supplies the structures of the first, second, and third intercostal spaces, mm at base of neck, and mm dorsal to the first few thoracic vertebrae

-arises from subclacian opposite the origin of the internal thoracic artery, medial to first rib

-emerges from thoracic inlet to supply the base of the neck and te adjacent scapular region

-arises from ventral branches if the C5-7

-both motor and sensory to the corresponding half of the diaphragm excepts at its periphery

-ventral branches of the first 12 thoracic spinal nerves

-have lateral and ventral cutaneous branches and branches medial to these that go largely to the mm

-dorsal 1st 3 come from a branch of the costocervical trunk

-last 9 come from the aorta

-ventral: from internal thoracic artery and vein

-emerge from axilla between the latissimus dorsi and deep pectoral muscles

-nerve: motor to the cutaneous trunci (on ventral border)

terminal branch of the internal thoracic artery that emerges from the thorax in the angle between the costal arch and sternum

-gives rise to the cranial superficial epigastric artery

-perforates the muscle and runs caudally on its external surface

-supplies the skin over the rectus abdominis and the caudal thoracic/cranial abdominal mammae.

-lies dorsal to the deep pectoral muscle and caudal to the large axillary vein coming from the arm

-lymph vessels of the thoracic wall and deep structures of the limb drain into this node.

-a bi-lobed, compressed structure situated in the cranial mediastinum

-largest in the young dog and atrophies with age until only a trace remains

-caudal part of the thymus is molded on the cranial surface of the pericardium

-a flat, fleshy muscle on the medial surface of the costal cartilages of ribs 2-8

-Its fascicles extend from the costochondral junctions to the sternum.

-layers that cover the sides of the partition between the 2 pleural cavities. -Mediastinum includes the two mediastinal pleurae and the space between them; encloses, the lymph nodes, the heart, the aorta, the trachea, the esophagus, the vagus nerves and the other nerves and vessels

=>Cranial part: lying cranial to the heart

=>Middle part: contains the heart

=>Dorsal part: dorsal to the heart

=>Ventral protion: ventral to the heart

=>Caudal part: lying caudal to the heart

-Pericardial mediastinal pleura is the portion covering the heart

-serous membranes that cover the lungs and line the walls of the thorax. -Pulmonary or visceral pleura: closely attaches to the surfaces of the lungs, following all their small irregularities as well as the fissures that separate the two lobes.

-Parietal pleura:thoracic wall by the endothelial fascia

-Costal pleura: covers the inner surfaces of the ribs and their associated intercostal and transversus thoracis muscles

-Diaphragmatic pleura: covers the cranial surface of the diaphragm

-Mediastinal pleura: the layers that cover the sides of the partition between the two pleural cavities.

-Rami communicans connect to the ventral branches T1-2 and C7/8

-provides a pathway for postganglionic axons to reach the thoracic limb

-source of postganglionic axons C1-6 from corresponding vertebral nn

-a branch or plexus from the cervicothoracic ganglion following the vertebral artery through the transvers foramina

-the two branches of the ansa subclavia loop unite here

-lies at the junction of the ansa and the vagosympathetic trunk (appears as a swelling of the combined structures)

-in the neck, lies in the carotid sheath

-sympathetic portion carries preganglionic and postganglionic sympathetic axons cranially to structures in the head

-cranial nerve X:

=>supplies thoracic and abdominal organs, cardiac nn of heart, bronchi

-Dorsal and Ventral branches- between the azygos vein and the right bronchus on the right and the area just caudal to the base of the heart on the left

-Ventral vagal trunk- the right and left branches unite with each other to form this

-Dorsal vagal trunk- the dorsal branches of each vagus do not unite until farther caudally near the diaphragm, to form this (li   es dorsal to the esophagus)

-fibroserous covering of the heart

-Parts: inner parietal serous pericardium, middle fibrous pericardium, outer pericardial mediastinal pleura

-lies dorsocranial to the RV

-receives blood from the systemic vv and most of the blood from the heart

-thin concave fold of tissue present on the cranial part of the interatrial septal wall

-remnant of the passageway for blood from the right atrium to the left atrium in the fetus (foramen ovale)

-located between left atrium and ventricle

-composed of two major cusps, the septal and parietal

-between left ventricle and aorta

-consists of three semilunar cusps.

-is about twice as large as the right

-short trunk that leaves the left sinus and immediately terminates in a circumflex branch and a paraconal interventricular branch

lies on the serratus ventralis and scalenus cranial to the supraspinatus, covered by the omotransversarius and the brachiocephalicus

- receive the afferent lymph vessels from the superficial part of the lateral surface of the neck, the caudal surface of the head (including the ear and pharynx) and the thoracic limb

-larger than the continuation of the axillary in the arm

-passes caudodorsally between the subscapularis and the teres major and become subcutaneous near the caudal angle of the scapula

-leaves the dorsal surface of the subscapular near its origin

-->supplies a part of the teres major and latissimus dorsi and ends in the skin.

-a caudal branch of the brachial in the distal third of the arm

=>supplies the triceps, the ulnar nerve, and the elbow

-continuation of superficial brachial artery (medial and lateral ramus arise from this)

-->supply blood to the dorsum of the forepaw via the dorsal common digital arteries

-continuation of the cranial vena cava on the roof of the abdomen

-formed by the union of the left and right common iliac viens

-in carotid sheath and runs along the trachea

-includes: caudal thyroid a, cranial thyroid a, internal carotid a, external carotid a, occipital a, cranial laryngeal a, lingual a, fascial a, sublingual a, caudal auricular a, superficial temporal a, maxillary a

-third branch of the aortic arch

-->curves ventrally within the mediastinum to pass b/n the transversus thoracis and sternum--> follows the sternum and tunnels below the diaphragm to continue as the cranial epigastric a

-on the right lung at the 4th-5th intercostal spaces

-is continuous with the fissure between cranial and middle lobes, thus allowing a clear path to the ventral convexity of the heart (direct to the right ventricle)

-midway between the shoulder and the elbow

-L: b/n 7=8th intercostal space

-R: b/n 6-7th intercostal space

What are the unique functions of the following:

a) coronary artery

b) bronchial arteries

c) pulmonary arteries

d) pulmonary veins

a) supply the mm of the heart

b) supply the lobes of the lungs

c) take deoxygenated blood from the RV to the lungs

d) take oxygenated blood from lungs to the LA

Definition: lies on the caudal ascpet of the atrial surface ventral to the coronary sinus that enters the RA

-contains the terminal branch of the left coronary a

-runs caudally across the lateral surface of the axillary lymph node and along the dorsal border of the deep pectoral ventral to the latissmus dorsi

-arises from the axilary a distal to the external thoracic

-branch of C6/7 b/n the supraspinatus and subscapularis mm near the neck of the scapula

=>supplies the supraspinatus and  infraspinatus mm

-a branch of C6/7

-supplies subscapularis

-arises from C6-8

-supplies corachobrachialis, biceps brachii, and brachialis

-arises as a branch from C7/8

-enters space b/n the subscapularis and the teres major on a level with the neck of the scapula

-supplies by the axillary n, teres major, teres minor, deltoideus, part of subscapularis

-arises primarily from C8 n

-supplies the latissmus dorsi m

-arises from the last two cervical and first two thoracic spinal nn, runs a short distance distally with the trunk of the median and ulnar nn and enters triceps distal to the teres major

-motor to all extensor mm of the elbow, carpal, and phalangeal joints: trceps, tensor fasciae antebrachii, and anconeus

-cranial division of the common trunk, runs to the antebrachium in contact with the caudal surface of the brachial artery

-mm of the forearm and to the skin of the palmar surface of the paw

-caudal division of the common trunk, searates from the median n in the distal arm and crosses the elbow caudal to the medial epicondule of the humerus

-supplies flexors and sensory to caudal aspect of antebrachium

-the continuation of the brachial a beyond the origin of the common interosseous

**principal source of blood to the manus

-this arch gives rise to the palmar common digital aa

-courses to the palmar surface of the manus

-supplies the extensors of the elbow, carpus, and digital jnts AND sensory to the skin on cranial and lateral surfaces of forearm and dorsal surface of carpus

-Deep branch: crosses the medial surface of the extensor carpi radialis and courses into the forearm with the brachialis m

-Superficial branch: divides into 3 branches, one following the cranial superficial antebrachial a to cephalic vein, one following lateral side of sephalic v, and enters forearm with cranial superficial antebrachial a

-runs distally into the antebrachium with the brachial a, passes through the carpal canal with the median a

-branches to supply sensory to palmar surface of the forepaw

-innervates pronator teres, pronator quadratus, flexor carpi radialis, superficial digital flexor, radial head/ulnar head of deep digital flexor

**no autonomous zone

-diverges caudally from the median n at distal third of the arm and enters the antebrachial mm caudal to the medial epicondyle

-distributes to flexor carpi ulnaris and unlar/humeral heads of DDF

-Dorsal branch: arises and becomes subcutaneous on lateral surface=> supplies lateral surface of metacarpus and 5th digit

-Palmar branch: on deep surface of flexor carpi ulnaris then enters lateral side of carpal canal and divides into superficial and deep branches => sensory to palmar surface of forepaw and motor to intrinsic mm of forepaw

-originates from the pudendoepigastric trunk emerges from the superficial inguinal ring corses caudoventrally to the cranial border of the gracilis

=>small branches supply labia (female) and scrotum (male)

-large continuation of the external pudendal a dorsal to the superficial inguinal lymph node, runs cranially to the deep surface of the inguinal mamma and supplies the mammary branches

=>in male: supplies the prepuse

-lie adjacent to the caudal superficial epigastric vessels and cranial to their origin from the external pudendal vessels, course through inguinal canal

=>drain the mammae, prepuse, scrotum, and ventral abdominal wall cranially to the umbilicus

-cranial to the cranioventral iliac spine, perforate the internal abdominal oblique and appear superficially; arises from the aorta

=>supplies caudodorsal abdominal wall

-cranial to cranioventral iliac spine, perforate internal abdominal oblique and apear superficially; arises from 4th lumbar spinal n

=>cutaneous to cranial and lateral surfaces of the thigh

-arises from ventral branches of the 3rd and 4th lumbar nn; bound by fascia to the external pudendal v medial to the spermatic cord

=>innervates cremaster m, skin covering the inguinal region and proximal medial thigh of both sexes, and part of prepuce in male

-a diverticulum of the peritoneum present in both sexes

=>Parietal vaginal tunic: the outer layer of vaginal tunic; extends from the deep inguinal ring to the bottom of the scrotum

=>Visceral vaginal tunic: closely fused with the testis and epididymis; surrounds the ductus deferense; deep to parietal vaginal tunic

-(ductus deferens + testicular a + testicular v)

-carried through the inguinal canal by the descent of the testis

-carries the spermatozoa from the epididymis to the urethra; arises from the tail of the epididymis at the caudal end of the testis and is attached to the mesorchium by mesoductus deferens

-accompanied by the deferent a and v

-passes cranially over the testis, medial to the epididymis

-lies on lateral side of testis

-Head: cranial extremity, where the epididymis communicates with the testis

-Tail: caudal extremity, continuous with the ductus deferens

Definition: Inguinal canal

-contents?

-short fissure filled with CT b/n the abdominal mm; extends b/n the deep and superficial inguinal rings (bounded laterally by the aponeurosis of the external abdominal oblique/ cranially by the caudal border of the internal abdominal oblique/ caudally by the caudal border of the aponeurosis of the external abdominal oblique/ medially by the superficial surface of the rectus abdominis)

=>Male: vaginal tunic and spermatic cord

=>Female: vaginal process and round ligament of the uterus

=>both: external pudendal vessels and genitofemoral n