The Developing Fetuses of your Mastino Napoletano puppies
The Developing Fetuses of your Neapolitan Mastiff puppies.
Up to the time it enters the uterus, the morula is sustained by the oviduct's epithelial secretion; after nidation in the uterus, the blastula is directly connected with the dam's circulatory system. At this stage, the embryos lie in a row down the length of the two uterine horns. In the early phases of gestation, the uterine horns resemble strings of beads with each embryo laying separately, enclosed in its own individual fetal membranes. As the fetuses grow large toward the end of pregnancy, the indentations gradually disappear, and the fetal membranous sacs end up touching one another along the lengths of the uterine horns. The placental sac is, firstly, almost a circular form. As the pregnancy progresses, the shape alters until it become elliptical. The individual fetus is enveloped in four embryonic membranes: the amnion is the puppies immediate inner covering; the chorion forms the outer covering; and the allantois and yolk sac lie in between these two. The embryonic secretion is transferred via the allantois to the dam's bladder and bowels. As the fetuses develop, the inner sac-the amnion-fills with a fluid in which the embryo swims. The urine that passes through the allentois forms a second, liquid cushion so that the fetus is very well protected against outside physical forces.
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