الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The present study was performed on 104 pregnant camel uteri with fetuses of crown¬length (CRL) ranging from 2.5-116 cm. The tissues were prepared for gross anatomy, microscopy, scanning electron microscopy of the exposed surfaces and vascular corrosion as well as for transmission electron microscopy.
The feto-maternal contact and anchoring are described as they gradually developed the progress of pregnancy. At the beginning, of the early-pregnancy stage (2.5-30 cm ) the chorioallantoic membrane followed the rather smooth endometrial surface without . g villi or protrusions. At the end of this stage the endometrial surface differentiated into w troughs separated by thick ridges, while the complementary fetal side consisted of
ed or globular protrusions and shallow troughs. During the mid-pregnancy stage (31-70
) the maternal troughs and the corresponding fetal protrusions were greatly increased . At the late-pregnancy stage (71-116 cm CRL) the maternal side developed a distinctly
ed trough system into which the corresponding fetal microcotyledons were interlocked I resulting into a stable anchored materno-fetal interrelationship.
The form and arrangement of the fetal and maternal microvascularization were studied three dimensional level using a 4: 1 mixture of mercox and methylmethacrylate. In the
stage of gestation, the maternal vasculature were arranged as densely meshed capillary k of shallow grooves and low ridges with tops of parallel oriented capillaries. Within
appeared as islands formed by widely meshed vascular s. At the end of this stage the capillary network of the maternal placenta consisted of and short ridges. The corresponding capillary network of the fetal placenta consisted e-like protrusions and shallow troughs. The fetal arterioles supplying this network gave illaries of smaller diameters to the troughs and others of larger diameters to the
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At the fetal protrusions the precapillary arteriole took a peripheral situation to the postcapillary venules arose at the base. At the mid-pregnancy stage the
al capillary network of the trough-ridge structure became deep and honeycomb-like. In network the maternal arterioles could be followed to the top of the ridges. At these ’ons the precapillary arterioles led to the capillary network of the ridges which continued nn the side and bottom of the troughs. The postcapillary venules arose to join the venous
underneath the capillary network of the ridges as well as at the base of the troughs. The arteriole could be traced to the top of the fetal protrusions or micro cotyledons, while the
7 or 8 prevenous connecting capillaries to join the fetal venule at the of the protrusions. In the late stage of pregnancy both fetal and maternal capillaries e smaller in diameter and more flattened. The honeycomb-like structure of the maternal ta developed into a more densely meshed capillary network of a distinct caveous type of s. In this network the corresponding densely meshed capillary network of the fetal
creating a characteristic vascular architecture required for o-fetal substance exchange.
Although the one-humped camel placenta remained epitheliochorial in arrangement hout the whole length of gestation period, thinning of the transplacental intervascular ce to be about 9 /lm or less at the late stage of pregnancy was recorded. This thinning due to reduction of the height of the epithelium as well as indentation of both trophoblast uterine epithelium by their corresponding capillaries. This indentation was more evident at
of the fetal microcotyledons, while at the base the trophoblast cells remain
The areola in the one-humped camel was of regular type whereas one uterine gland into the areolar cavity. The first areola formation was observed histologically in the . n of 4.5 cm CRL. The areola developed gradually with the progress of pregnancy and it
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