Part 190

In the sheep and goat there is a lymph gland at the middle of the neck, in the angle between the spinalis and complexus, covered by the splenius. It receives vessels from the atlantal gland and sends efferents to the prescapular gland.

The =prescapular= or =superficial cervical lymph gland= is situated at the anterior border of the supraspinatus under cover of the mastoido-humeralis and omo-transversarius. It is elongated and may be an inch or more in width and four or five inches long. Two occur in exceptional cases.

A chain of hæmolymph glands lies along the front of the shoulder, covered above by the trapezius. Others are frequently found (in the calf especially) on the surface of the omo-transversarius at the point where it passes under the mastoido-humeralis (Forgeot).

FIG. 478.—SUPERFICIAL LYMPH GLANDS OF COW PROJECTED ON SURFACE OF BODY.

1, Submaxillary; 2, subparotid; 3, atlantal; 4, parapharyngeal; 5, anterior cervical; 6, middle cervical; 7, prescapular; 8, precrural. (With use of fig. in Ellenberger-Baum, Anat. f. Künstler.) ]

The =posterior cervical= or =prepectoral lymph glands= number commonly three or four on each side. One or two are placed on the brachial vessels, one below the brachial vein at the first rib, and one at the junction of the common trunk of the external and subcutaneous thoracic veins with the brachial.

The =intercostal lymph glands= are situated, as in the horse, at the upper parts of the intercostal spaces. Associated with them are hæmolymph glands.

The =sternal lymph glands= are situated along the course of the internal thoracic artery at the lower part of the intercostal spaces. The largest is close to the thoracic inlet. Several glands occur in the fat about the apex of the pericardium.

4. Several =anterior mediastinal lymph glands= are placed along the œsophagus and the trachea. Hæmolymph glands occur here also.

Usually three large =bronchial lymph glands= are present (Fig. 289). One is situated at the origin of each chief bronchus and the third is under the trachea at the origin of the special bronchus of the apical lobe of the right lung. Another may lie between the aorta and the left branch of the pulmonary artery. These glands are often pigmented. Other small nodes are situated on the bronchi within the lungs.

The =posterior mediastinal lymph glands= comprise two or three of large size placed along the dorsal wall of the œsophagus. There may be a single gland about eight inches (ca. 20 cm.) long, the anterior half of which lies on the œsophagus (Fig. 289). A small gland is situated in the acute angle formed by the posterior vena cava and the diaphragm.

A single =axillary lymph gland= is situated on the distal part of the teres major on the course of the vein from the latissimus dorsi.

The =lumbar lymph glands= form an irregular series scattered along the abdominal aorta and posterior vena. A bean-shaped =renal lymph gland= occurs at the hilus of each kidney. Hæmolymph glands occur along the course of the aorta.

FIG. 479.—INTESTINE OF OX, SPREAD OUT.

Ca, Cæcum; C, colon; D, duodenum; H, ileum; J, jejunum; R, rectum; m, mesenteric lymph glands. (After Edelmann.) ]

The =internal iliac lymph glands= comprise a group of five or six at the termination of the aorta and the origin of the vena cava. A discoid gland, two inches or more in diameter, occurs near the side of the pelvic inlet at the angle of divergence of the circumflex iliac artery from the external iliac. A small gland is sometimes found at the origin of the prepubic artery.

The =external iliac lymph glands= number commonly two on either side, and are situated near the point of the hip in front of the anterior branch of the circumflex iliac artery.

The =superficial inguinal lymph glands= are situated centrally below the prepubic tendon and in the narrow space between the origins of the graciles. In the male there are usually two or three on either side of the penis behind the sigmoid flexure. In the cow they are =supramammary=, i. e., are situated above the posterior margin of the base of the udder; two large glands which are in apposition with each other medially are constant, and above these there are often two smaller glands.

An =ischiatic lymph gland=, which is discoid and usually about an inch in diameter, is situated on the lower part of the sacro-sciatic ligament near the lesser sciatic notch under cover of the biceps femoris.

An =anal lymph gland= is situated on the retractor ani on either side.

The =gastric lymph glands= are numerous and comprise: (1) a chain along the course of the right ruminal artery and two or three in the left groove of the rumen; (2) several on the reticulum above and below the junction with the omasum; (3) a series along the course of the superior omasal vessels and the lesser curvature of the abomasum; (4) an extensive chain along the ventral face of the omasum and the great curvature of the abomasum at the attachment of the great omentum.

Two or three large =hepatic= or =portal lymph glands= are found at the upper part of the portal fissure of the liver.

No lymph glands occur at the hilus of the spleen. The efferent vessels from the spleen appear to go to glands along the course of the cœliac artery.

A large discoid =cœliac lymph gland= lies on the pancreas and the cœliac artery, covering the latter as it gives off its primary branches.

The =mesenteric lymph glands= are large and numerous. They form a chain in the lower part of the mesentery along the course of the great mesenteric artery. They are chiefly elongated and narrow, and some have a length of six to eight inches (15 to 20 cm.) or more. Sometimes several unite and form a narrow band about two feet in length. A large gland occurs at the origin of the spiral part of the colon, a group is found near the anterior mesenteric trunk, and others are scattered along the coils of the colon, which are best seen on the right side. A chain of small lymph glands extends along the terminal part of the colon and the dorsal face of the rectum.

The =precrural lymph gland= is situated on the aponeurosis of the external oblique at the anterior border of the tensor fasciæ latæ a short distance above the stifle. It is elongated like the prescapular gland and may be six inches (ca. 15 cm.) long. Several subcutaneous hæmolymph glands occur in this vicinity; others are situated further forward on the flank not far from the last rib. There is usually a round, flattened lymph gland about an inch in diameter on the upper part of the quadriceps femoris under cover of the tensor fasciæ latæ, and one or more small ones occur on the surface of the latter muscle.

No =deep inguinal lymph glands= are present.

A single =popliteal lymph gland= an inch or more in length is situated somewhat lower down on the gastrocnemius than in the horse, behind the tibial and peroneal nerves.