جستجوی مقالات مرتبط با کلیدواژه « جنین گوسفند » در نشریات گروه « دامپزشکی »

Toxoplasma gondii is an intracellular parasite, which is widely prevalent in sheep throughout the world. Parasite infection can occur pre- or post-natally. Congenital ovine toxoplasmosis occurs following a primary infection in a pregnant ewe and leads to abortion and stillbirth of the fetus causing important economical losses to sheep industry. The present study was conducted to evaluate the presence of T. gondii DNA in brain samples from fetuses of slaughtered ewes in Khorramabad, west of Iran. In total, 60 brain samples of ovine fetuses were collected. Examined fetuses were categorized in three age groups (4 months). Fifty grams of each sample was homogenized by mortar and pestle. DNA extraction was performed using a DNA isolation kit (MBST, Iran). A polymerase chain reaction (PCR) which targets the repeated element (RE) of the organism was used for tissue samples. Brain samples were considered T. gondii-positive if the expected band size (529 bp) appeared. T. gondii was detected in 4 out of 60 (6·7%) examined fetuses. No case was recorded in the age group

The study of animal development by a dynamic perspective on gross anatomy often provides amplified pattern to reveal the more complex anatomy of the adult. This is especially helpful in understanding system whose components drastically change their relation positions during developmental growth, such as urogenital organs.
OJECTIVES: The aim of present study was to study morphologic and morphometric development of sheep kidneys during fetal period.
Sixty fetal kidneys obtained from 30 sheep fetuses were divided into three groups (70-100, 100-120, 120-145 days) according to body length. Topography, dimensions, and weight of kidneys were evaluated.
The kidneys were located totally in the lumbar region of the sides of the median plane. The position of kidneys relative to the transvers process of lumbar vertebrae was different in the age groups. The fetal kidney was not located at the same level of adult position even at the end of fetal period. The right kidney was consistently slightly cranial to left kidney. The left kidney was in contact with dorsal sac of rumen in all age groups. The right kidney was covered by ventral surface and a small part of the lateral surface of right lobe of liver, but with advancing age, the contact are of right kidney with caudate process of liver showed tangible reduction and such a contact limited eventually to the cranial pole of kidney. Means of dimensions and weight of kidneys increased with gestational age during fetal period. There were no sex and laterality differences in any parameters.
Topography of fetal sheep kidneys relative to the lumbar vertebrate and their contact area of the kidneys with right lobe and caudate process of liver differed extremely from that of adult sheep kidney. It seems that the emergence of positional asymmetry of kidneys and changing contact area of right kidney exhibited an intimate relationship with the cranial shift and grow rate of right lobe and caudate process of liver during fetal development. The morphmetric results of fetal sheep kidneys were in agreement with the morphometric findings of humans and bovine kidneys.

This study was conducted on the atrioventricular node (AVN) and atrioventricular bundle (AVB) of five four-month-old ovine fetuses. The histological structure of these components was studied by routine histological techniques and use of specific staining methods. The AVN was caudally located adjacent to the root of the aorta. It was almost spherical in shape and consisted of twisty cells. The node was mainly composed of “P” cells. There were not seen internodal pathways in the heart of four-month ovine fetus. The AVB was a direct continuation of the AVN and it passed through the fibrous ring toward the apex of the interventricular septum. At this place the right bundle branch (RBB) was ramified. The cells of the AVB were wider, shorter and lighter than normal myocardial cells. Some of the bundle cells have been changed to purkinje cells, whereas some others still did not represent typical characteristics of purkinje cells.