Agriculture Reference
In-Depth Information
be exposed by making an incision lengthwise through
this vessel and continuing the incision 2.5 cm deep into
the lumbar suet.
D:
Kidneys and adrenal body.
E:
Receptaculum chyli. The renal lymph nodes vary in size
and number.
Superficial inguinal (male)
P:
These lie in the mass of fat about the neck of the scro-
tum and behind the spermatic cord.
D:
External genitals
and adjoining skin area.
E:
Deep inguinal when present
or, failing this, the internal iliac.
Mesenteric
P:
These comprise a large number of elongated nodes
which lie between the peritoneal folds of the mesentery
and receive lymph from the intestines. These nodes may
be divided into a small duodenal group which drains the
duodenum, the efferent lymphatics passing to the portal
nodes of the liver and a jejuno-ileal group ranging in
number from 10 to 50 and 0.5-12 cm in length. The long
nodes form the main chain parallel to and some 5 cm
from the intestine, while the small nodes are scattered
throughout the mesentery between the small intestine
and the colon.
D:
The small intestine (jejunum and
ilium).
E:
Receptaculum chyli.
Supramammary (female)
P:
These lie above and behind the udder; there are usu-
ally two present on each side, one large and one small,
the larger pair, about 7.5 cm in size, approximating to
each other and the small pair being found above or in
front of the larger pair and 0.5-1.5 cm in size. In the
heifer, these nodes may be found on a straight line level
with the cut pubic tubercle.
D:
Udder and external geni-
tals.
E:
Deep inguinal when present or internal iliac.
Deep inguinal
P:
In the inguinal canal and frequently absent; when
absent, the internal iliac functions in its place.
D:
Hindlimb and abdominal wall.
E:
Internal iliac.
According to some authors, the deep inguinals are part
of the external iliacs.
Splenic
Splenic lymph nodes are absent in the ox and sheep.
Lymph drained from the spleen passes to the gastric
chain of the lymph nodes. Several splenic lymph nodes
are present in the horse and pig.
Ischiatic
P:
This lies on the outer aspect of the sacrosciatic liga-
ment and is exposed by a deep incision on a vertical line
midway between the posterior part of the ischium and
the sacrum.
D:
Posterior pelvic organs and also receives
efferents from popliteal node.
E:
Internal iliac.
In many countries in Africa, the ischiatic node is
incised on routine post-mortem examination of beef
carcases because the bites of the tick
Hyalomma rufipes
,
which attaches itself to the perianal region, frequently
cause abscess formation.
Gastric
P:
These are numerous and difficult to group satisfac-
torily; a number form a chain along the right and left
longitudinal grooves of the rumen.
D:
Walls of stomach
and spleen.
E:
Receptaculum chyli. The gastric group are
rarely incised in meat inspection.
Iliacs
These are situated near the terminal branches of the
aorta and are embedded in fat.
Internal iliac P:
This may be exposed by an incision
level with the junction of the sacrum and the last lumbar
vertebrae. Several nodes are present, lying some 18 cm from
the vertebrae and 1-5 cm in length.
D:
This node drains the
muscle and pelvic viscera, including the muscles of the sub-
lumbar region, pelvis and thigh; the femur, tibia, patella,
tarsus and metatarsus; the male and female genital organs;
and the kidneys. It receives efferent vessels from the exter-
nal iliac, precrural, ischiatic and superficial inguinal nodes.
E:
Lumbar lymph nodes and receptaculum chyli.
External iliac P:
A single or double node 1-2.5 cm in
length and situated laterally to the internal iliac. It lies
beneath the external angle of the ilium at the bifurcation of
the circumflex iliac artery but is sometimes absent on one
or both sides.
D:
Abdominal muscles, sublumbar area, pos-
terior part of the peritoneum and some efferents from the
popliteal node.
E:
Internal iliac and lumbar lymph nodes.
Sacral
P:
These are not constantly present and are unimportant.
If present, they are difficult to distinguish from the
medial iliac lymph nodes.
Precrural (sub-iliac)
P:
This node is known also as the prefemoral and is
embedded in fat; it may be exposed by an incision at the
edge of the tensor fascia lata, the incision being made
about 18 cm down from the apex of this muscle.
D:
Skin,
prepuce and superficial muscles.
E:
Internal iliac nodes.
The precrural nodes, draining the umbilicus, should
always be palpated in calves and if necessary incised.
Popliteal
P:
This is deeply seated in the round of beef and is
exposed by a deep incision along the superficial seam or
division which connects the ischium and os calcis, the
