Abdomen and Pelvis 
squamous epithelium (Fig. 5-15), which is separated from the mucosal 
lining of the glandular stomach by a distinct margo plicatus. 
At the level of the esophageal junction with the 
forestomach, a fissure bordered by two well-defined 
labia runs along the lesser curvature {curvatura 
ventriculi minor) to the transition of the two stom- 
achs. The labia continue along the internal surface 
of the glandular stomach for about 3 or 4 mm, and 
their edges are considerably elaborated (Fig. 5-14). 
When fully distended, the glandular stomach is be- 
tween 30 and 40 mm long and attains a diameter of 
20 to 25 mm. When empty, the glandular stomach 
is bordered by the transverse colon, the duodenum 
and the head of the caecum; its greater curvature 
{curvatura ventriculi major) is oriented to the right 
(Fig. 5-14), and in an extremely distended state, it 
rests against the left lateral lobe of the liver. The 
parietal surface (Jacies parietalis) of the glandular 
stomach is affixed to the left lateral lobe of the liver 
by the hepatogastric ligament. The greater curva- 
ture is bordered sinistrodorsally by the ventral end 
of the spleen; when full, it is also bordered ventrally 
by the abdominal wall, to the right by the pancreas 
and, in some cases, by a portion of the S-shaped 
flexure of the ascending colon. Since the lesser curv- 
ature is markedly concave, the cardia {pars cardi- 
aca) and pylorus are closely applied, with the 
opening to the forestomach lying caudal to the 
pylorus (Figs. 5-12, 5-14). 
The largest part of the glandular stomach is lined with gastric glands 
consisting of tall columnar epithelium with many goblet cells (Fig. 5- 
16). 
A circular constriction formed by the pyloric 
sphincter (m. sphincter pylori) separates the py- 
lorus {pars pylorica) from the rest of the stomach. 
This segregated portion of the stomach tapers 
sharply towards the duodenum. 
The serous surface of the glandular stomach is grayish-red in color, 
smooth, thick and surrounds an inner circular and an outer, faintly 
visible, longitudinal muscle layer. Extending up to 1.5 mm in height, 
the pyloric margin is white in color and possesses varying amounts of 
villi; however, macroscopically, one cannot distinguish color differ- 
ences among the cardia, fundus {fundus ventriculi) and pylorus of the 
glandular stomach. The area with cardiac glands {gll. cardiacae) is 
found in varying striations along the pyloric margin, while the pyloric 
glandular zone {gll. pyloricae) circumscribes the pylorus. 
5.5.2.3 Proximal Duodenum 
The proximal, or cranial, duodenum {pars cra- 
nialis) arises from the pylorus, somewhat cranial 
and dorsal to the hilus of the liver (Fig. 5-17), 
where it doubles back caudoventrally to the right 
at the first flexure {Jlexura duodeni cranialis) be- 
fore turning caudally at the right lateral hepatic 
lobe. The proximal duodenum is fixed to the liver 
by the hepatoduodenal ligament of the lesser 
omentum. 
5.5.2.4 Liver 
The functions of the liver {hepar) are manifold. 
During fetal life, it contains focal areas for the for- 
mation of blood, which function until birth. Even 
in the newborn animal, the liver occupies a large 
part of the abdominal cavity, but then it rapidly de- 
creases in size. The liver is an important storage 
organ for glycogen produced from digested carbo- 
hydrates in the intestines and supplied via the por- 
tal blood. It can also store fat and protein in its 
cells. In addition to its storage function, the liver 
also has an excretory function. It synthesizes ni- 
trogenous metabolites to urea and uric acid, which 
are then excreted by the kidneys. The liver extracts 
toxic substances from the blood and detoxifies them. 
Moreover, the liver secretes bile and removes the 
metabolic products of red blood cells that originate 
in the spleen. 
The largest organ of the body is the liver. The 
size and weight of the liver can vary greatly; but, 
on an average, it weighs about 15 g in both males 
and females (Tables 2, 5). In an exsanguinated 
state, the liver is brown in color; however, this color 
is dependent upon the blood content, the age and 
especially the nutritional condition of the animals. 
In especially fat hamsters, usually in the fall, the 
liver is more yellow in color due to abundant fat 
deposits. 
Due to the peritoneal lining, the surface of the 
liver is smooth and shiny. Its structure of many 
small lobules is macroscopically visible only if 
abundant interlobular connective tissue is present. 
Because of its elastic consistency, the liver accom- 
modates the neighboring organs. Deep fissures 
(Figs. 5-18, 5-19) divide the liver into the follow- 
ing parts: a bipartite left portion with the left lat- 
eral lobe {lobus hepatis sinister lateralis) and the 
left medial lobe {lobus hepatis sinister medialis); an 
intermediate supraportal caudate lobe {lobus cau- 
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