Prenatal Study of Testes Growth and Histological Development 1- Fetal Sheep.

Amin F.A S M

doi:10.30539/iraqijvm.v34i1.679

Abstract

This study was conducted on 200 samples of females Karadi sheep genitalia contains 207 fetuses . These samples were collected from slaughter house in Sulaimani reigion during the period from June 2007 to the end of May 2008. Sheep genitalia consisted of 193(96.5%) single and 7(3.5%) twin fetuses, amonge them 122 (58.92%)and 84(41.06) were in the right and left horns ,respectively. The genitalia that contain fetuses with clear external sex organs was 141, of these 74 male and 67 female fetuses different Crown Rump Length (CRL), while 66 fetus their sex could diagnosis after abdominal opened. The results showed the weight of the fetal body and testes as well as the length of scrotum were increased with an increasing of the fetal CRL. The appearance of the fetal testes in the inguinal ring was when CRL=22cm .80 day; in the scrotum 32 cm. 100 day ; Histological sections of the fetal testes were showed the density of fibroblast layer and connective tissue capsules as well as the appearance of seminiferous tubules containing a few spermatogonia cells and small sertoli and leydig cells at early CRL=10 cm 55 day; , with increasing fetal CRL the seminiferous tubules filled with different types of spermatogonia and spermatocytes cells as well as increasing in the number of sertoli and leydig cells were recorded at CRL= 20.3 cm. 75 days; While the metamorphosis spermatid were seen at CRL=24cm . 80-85 day; Conclusions : Fetal sheep seminiferous tubules early in gestation contain different types of spermatognium and spermatocyte cells appear in the testes after 50 days, and metamorphosis spermatid were seen after 80 days of intra uterine life no sperm was seen in fetuse testes.. It was concluded that the fetal testes in early gestation could be secreted testosterone which lead to increases in fetal testes development and growth of the germinal and somatic cells

Highlights

Karadi sheep are fertile small ruminants breed in Sulaimani ‫ق‬egion; they are used mainly for the production [1]
The total number of male fetuses of different Crown Rump Length (CRL) recorded was 74(35.74%)and the number of genitalia that contained 66(32.03%) fetuses whose external fetal sex organs could not be detected was 60 genitalia( 6 genitalia was contain 2 fetus) Table 1. shows that the fetal weight was steadily significantly increased from 2.5cm to 43.86cm CRL
This is the first study that follow up fetal testis weight, migration and histological development of different germinal cells in the seminiferous tubules and Leydig cells during intra uterine life

Summary

Introduction

Karadi sheep are fertile small ruminants breed in Sulaimani ‫ق‬egion; they are used mainly for the production [1]. The development and function of the testes in sheep fetuses are known to be critically depends on circulating fetal gonadotrophin concentration [2]. McNatty[3] reported that the physiologically relevant stages of fetal development are includes: after sexual differentiation, early central nervous system (CNS) androgen-responsive phase and day 50 of gestation. Middle of the CNS androgen-responsive phase, before pituitary function ( 4 and 5 ; day 65 of gestation); and after the onset of gonadotrophin secretion (5;day 110 of gestation.). There was no data available considering the size, location, of fetal testes as well as the histological study of the development of the fetal testes. The present study was designed to investigate the histological development of fetal testes and to determine the location, size, and migration of fetal testes throughout the majority of intra uterine life of Karadi sheep.

Results

Discussion

Conclusion