الفهرس | Only 14 pages are availabe for public view |
Abstract This work was carried out on Fiftyfour buffalo embryos and fetuses from 49283 daysold collected from ElMansoura abattoir, embryos of 4974 daysold, were fixed in 10% buffered formalin, then specimens were excised from the flank region and ear concha, then processed and treated with the normal histological technique. whereas, fetuses of 81283 daysold, were perfused with a warm normal saline, then injected with an equal mixture of Indian ink and bovine serum through the umbilical vessels. The specimens were fixed in 10% formalin for 12 weeks. The specimens are excised from muzzle, cheek, shoulder, flank, thigh, and digit as well as the ear concha, then dehydrated in alcohol and cleared in benzol followed by an equal mixture of methyl and benzyl benzoate, then examined by aid of the light and the dissecting stereomicroscope. The development of the cutaneous vasculature were classified into four stages. The first stage (4974 daysold), The miniature of the blood vessels in form of aggregated haemangioblast cells. The second stage (81112 daysold), The cutaneous vascular pattern represented by scarcely scattered Rami arteriosi and Rami venosi primitively at all dermal layers without any sort of anastomoses. The third stage (126187 daysold), The primary cutaneous vascular pattern which represented by the primary arterial Retae and venous plexuses were recognized and the skin was divided into unit vascular zones The skin of the muzzle showing many arterial loops. The fourth stage ( 198283 daysold), The mature cutaneous vascular pattern were attained in addition the formation of the perifollicular network around the hair follicle. The morphogenesis of the vasculature within the concha auriculae divided into four stages; The first stage (4974 daysold) the ear concha revealed the primitive vascular architecture like the general skin. The second stage (81112 daysold) the primitive arborization pattern of the conchal blood vessels is recognized in form of five arterial Rami and three main veins. The third stage (126187 daysold) the conchal blood vessels showed a premature pattern of orientation . The fourth stage (198283 daysold), the final constructive pattern were recognized in form of a complex subepidermal, perichondral Retae. |