Histology of ovine placenta during gestation periods


Abstract: Placetomes were collected from 93 pregnant slaughtered Ewes at different gestation periods , from AL.Falluja slaughter house during the periods from 2, Jully 2009 to 30, December ,2010 . Tissue specimens for microscopic examination were taken from the centers of the sampled placentomes .Immediately following collection ,the samples were fixed in 10% bufferd neutral formalin for 24 h .Tissue specimens were dehydrated in a graded series of alcohol , cleared by xylol and embded in paraffin .Histologic section were cut at 3-4 µm thickness ,Stained with hematoxylin and eosin(H&E) (6).The period of gestation were measured according to Richardson (7) with aquation of x =2.1(Y+17) as x= gestation period in day and Y=the crown Rump. Histologic examination during early pregnancy (30 – 40 d) Showed a pronounced BNC with anumbe of nuclei with in each cellular boundary in the uterine epithelium indicates that possible fusions are restricted , It is also there is an increase in blood vascularity. At 40 – 50 d of pregnancy, there was a further increase in caruncular vascularity by 2-fold characterized by increase capillary number and 2 to 3 – fold increase in capillary diameter. Endometrial gland hyperplasia showed during this period . Then placentomes showed grow in number and size until 8oth day. It was shown that the BNCS of the trophoblast increase in size, in polarity and in the number of their cytoplasmic granules as pregnancy advanced.