Trimester of Pregnancy

The present work was designed to investigate the histological developmental characteristic of metanephros has been done in the local bovine's fetuses in different stages of pregnancy. The study was performed on 24 bovine ́s fetuses distributed at six groups ( 1, 2, 3, 4, 5, 6 ) months gestational age collected from the slaughtered pregnant cows in the slaughterhouses in Babylon province. The present study showed that the metanephrose at 1 st month appear bean – shape composed of primary excretory duct, primitive renal calyex and not yet at the nephron forming stage. The histological study for different stages showed that differentiation and formation of the renal corpuscle, began in the bovine kidney before 2 nd month of pregnancy and it is passed through sequential and complex morphological stages in embryonic life, while the jaxtaglomerular apparatus is absent and the Henle loops are undifferentiating relatively in 2 nd month of gestation. The purpose of our study to provide a more complete quantitive histolodevelopmental description of the metanephros formation in bovine fetuses. ةسارد محنا نم يناثناو لولاا ثهثنا للاخ هيهحمنا راقبلاا ةنجأ يف هيذعبنا ةيهكهن هيروطت م يروبجنا سابع يزاغ رفعج ءارضخنا مساقنا ةعماج / يرطيبنا بطنا ةيهك ةصلاخنا : ٍهحمنا راقبلاا تىجا ًف تٌدعبنا تٍهكهن تٍجسىنا تٌروطخنا ثافصنا تساردن تٍناحنا تساردنا جممص تيفهخلر ميلاار ًيف ت ىهع تساردنا جٌاجا . ممحنا هر 42 ًيف تيععور رايقبا هٍىج جيس ٍرايجر 1 , 4 , 3 , 2 , 5 , 6 ميمحنا هير اريشا ) ارشنا ًف تٌدعبنا تٍهكنا ناب جئاخىنا ثارظا . مباب تظفاحر ًف رعاجمنا هر ثاىٍعنا جعمج لولاا تيبل تبيشح ممحنا هر ا هٌعاافا ةاىق هر هووكر اٍنوصافنا ثايرظا . نوايفىنا هٌويكح تيهلار ىينا نلاا دحن مصح منو ًئادب يوهك ساكو هٍئادخب ميبق ادبح تٌوهكنا تٌاكهن هٌوكخناو زٌامخنا ناب تٍهكنا روطخن تفهخلمنا ملاامهن تٍجسىنا تساردنا 4 ايمحو ميمحنا هير اريش كن روايجمنا عايرجنا ايمىٍب تيٍىٍىجنا ميلاامنا اايىرا ةديقعرو تيبقاعخر ميلاار ل يخ ايٍر ًيهى ةوايعو ةويجور ايٍر تيبٍب تيٍهكنا هٌويكخن ميراك ًيمك ًجيسو يصو اٍفويخن وي اىخيسارة هير ايغنا . ممحنا هر ًواثنا ارشنا ًف اٍبسو ةزٌامخر . تٍهحمنا راقبلاا تىجا ًف تٌدعبنا Introduction : The kidney is an important organ involved in the removal of unwanted nitrogenous substances, excess water and relative maintenance of osmotic concentration of the blood (Salehi and Euphrates Journal of Agriculture Science-6 (3): 1-16 , (2014) al-jebori . 4 ISSN 2072-3875 Morovati, 2012). The urinary system are derived from intermediate mesoderm, the nephrogenic plate and the permanent mammalian kidney begins to develop when the ureteric bud extends into the surrounding metanephric mesenchyme. The ureteric bud arises from an offshoot of the mesonephric duct invading the mesenchyme around it and ultimately forms the ureter, renal pelvis, major and minor calyces and collecting ducts,while the nephroblastic cells of the metanephric blastema, on contact with the ureteral bud, eventually develop into the nephron : renal corpuscle, proximal convoluted tubule, Henle loop and distal convoluted tubule (Shah et al., 2004 ; Hyttel et al., 2010). Because there is no sufficient studies about the kidney histogenesis in cow's fetuses so we suggest studying histomorphological description and the timing of first appearance of the components and parts of metanephrose at intrauterine life because it has economical importance in our country. Materials and Methods : The bovine foetuses were collected from the adult clinically healthy pregnant cows slaughtered in the abattoirs of Babylon province. The study was performed on 24 bovine ́s fetuses distributed at six groups ( 1, 2, 3, 4, 5, 6 ) months of gestational age. Their ages were estimated according to the crown rump length (CRL) as described by ( Evans and Sack, 1973). The CRL were measured for all fetuses ( CRL is the measurement from the vertex of the skull to the midpoint between the apices of the buttocks according to (Arthur et al., 1989). The CRLs at each stage are summarized in the histogram (1) by using verniae callaper. The body weight was recorded for each prenatal fetus by using sensitive balance are summarized in histogram (2). The weight, length, width and thickness of metanephros at each stage is summarized in table (1). Samples were taken directly from bovine ́s fetuses and fixed in 10% formalin to left for 72 hours. After fixation, the specimens were washed by tap water for 3-4 hours to remove the formalin solution and transferred to the following steps: dehydration, clearing and embedded and finally cutting and staining by using the rotary microtome and stained with H & E, Van-Geson and PAS stains (Luna, 1968). A computerized program, the Statistical Package for Social Sciences (SPSS) was used to calculate the statistics (Joda, 2008). Finally, the results of the study were recorded of different histological sections by light microscope and (MEM1300) digital eyepiece for microscope installation instructions. Euphrates Journal of Agriculture Science-6 (3): 1-16 , (2014) al-jebori . 3 ISSN 2072-3875 Histogram: 1. Show relationship between CRL of embryo and time of pregnancy Histogram: 2. Show relationship between weight of embryo and time of pregnancy Euphrates Journal of Agriculture Science-6 (3): 1-16 , (2014) al-jebori . 2 ISSN 2072-3875 Table (1) show weight, length, width and thickness of right and left kidney at each