Histogenesis of the skin of the one-humped camel [Camelus dromedarius]

ABSTRACT

The fetal epidermis appeared as a single layer of cells at 1.8 cm CVR length. Then increased in thickness by 39-43 cm CVR. The primordia of the stratum corneum was observed in fetuses with 87 cm. At CVR 95 cm the epidermis showed a general decrease in thickness. By 110-117 cm stage the epidermis could be differentiated into many strata. However, the stratum lucidum was not seen. There was a gradual increase in the thickness of dermis throughout the fetal life. At 34 The hair germ started to appear at 15 cm CVR and formed hair plug at 34 cm CVR. By 39-47 cm these hair plugs appeared as slanted column of cells and could be distinguished into primary and secondary with 59 cm length. At 87 cm the hair canal and the bulb were formed. Hair groups were recognized at 95 cm CVR and became clear in fetuses with 110-117 cm. At this stage, many of the hair had emerged from the skin surface. Sweat gland buds appeared as ental swelling on the primary hair plugs at 42 cm CVR fetal length and on the secondary hair plugs at 65 cm. These sweat gland primordia were canalized at 75 cm CVR. In fetuses with 87-110 cm length, the sweat glands appeared more developed. They were located more deeper in the fetal dermis at 117 cm. At 50 cm CVR the sebaceous gland rudiment was first recognized. By the stage of 59-75 cm they bulged into the adjacent dermis as a follicular cell budding and increased greatly in length and in size with the advance of age. At 95 cm, the secondary follicules showed small sebaceous buds. In fetuses with CVR 117 cm the sebaceous glands appeared more organized and became distinct in association with the primary hair. Those with the secondary follicles were short and small