In amphibians the germ cells arise in the vegetal pole region whereas in mammals the cells arise in the extraembryonic yolk sac mesoderm and then must . The process of Gametogenesis is stimulated by the FSH or Follicle . eggs of shark, bony fish, Reptiles, birds, prototherian, concentrated mainly in vegetal pole . marginal zone, transitional area between animal and vegetal hemispheres. maturation, process of gaining fully differentiated form. maturation promoting factor.

Author: Moogukazahn Vudogal
Country: Netherlands
Language: English (Spanish)
Genre: Marketing
Published (Last): 19 March 2004
Pages: 152
PDF File Size: 6.2 Mb
ePub File Size: 12.94 Mb
ISBN: 906-9-65668-112-8
Downloads: 48294
Price: Free* [*Free Regsitration Required]
Uploader: Vular

The parthenogenetic development of rabbit oocytes after repetitive pulsatile electrical stimulation.

Useful Notes on Gametogenesis (Spermatogenesis and Oogenesis)

Chronology of pre-implantation embryo development in goat and other farm animals, rabbit, mouse and human. Analysis of mouse oocyte activation suggests the involvement of sperm perinuclear material.

Depending upon the amount of yolk, it may be as small as 0. Development of the gametogsnesis ovary during fetal and early neonatal life and the effect of fecundity genes. Sperm and Egg Transport. Goat embryo production from in vitro matured heterogeneous oocytes fertilised by intracytoplasmic sperm injection ICSI technique.

Germ Cells and Fertilization, Austin, C. During this follicle and oocyte growth phase, oocytes not only acquire competency to resume meiosis, but also acquire ga,etogenesis maturity, also known as oocyte capacitation, both of which are required to ensure normal fertilization and embryo development Gosden et al.

A number of enzymes and factors that present in the female reproductive tract have been implicated to affect sperm capacitation, such as arylsulphatase, fucosidase and taurine.

Gametogenesis – Spermatogenesis – Oogenesis – TeachMePhysiology

The attachment of the sperm head to the ZP inevitably alters the permeability of the sperm plasma membrane, causing a transient change in the concentration of several intracellular ions Tulsiani et al.


Primary membrane is formed surrounding the plasma membrane of ovum and is secreted gametogebesis the ovum itself.

The tertiary membranes are secreted in oviduct when the ovum passes from ovary to outside. During the phase of maturation, the primary spermatocytes divide gametogeensis meiosis consisting of two successive divisions. Therefore, there is still a need for study some basic in vivo aspects of gametogenesis, fertilization and pre-implantation gametgoenesis process in goat which will not only fill up gaps of information but also help in the successful deigning of suitable ARTs for rapid improvement of goat industry.

This is supported by in vitro experiments in Xenopus laevisan amphibian species Brun,mouse Kimura and Yanagimachi, and human Palermo et vegteal. In mammals, fertilization process is internal and the male gametes spermatozoa must be introduced into the female reproductive tract at coitus or artificially.

The fusion site on the equatorial segment may be excluded from the acrosome reaction and the sperm plasma membrane is still intact on the apical part of the postacrosomal sheath and the equatorial segment.

Following penetration, the acrosome-reacted sperm passes through PVS and interacts with the sperm plasma membrane of the oocyte oolemma Schultz and Kopf, Factors affecting meiotic gameetogenesis in pig oocytes.

As already mentioned earlier, before penetrating into the oocyte, various biochemical changes occur in the spermatozoon including capacitation, AR and sperm oocyte interaction. Primary spermatocytes then undergo meiosis. These structural rearrangements facilitate the increasing energy and nucleic acid synthesis requirements of the developing oocyte and are a prerequisite to the oocyte achieving meiotic competence and embryo developmental potential.


These include various alterations in the plasma membrane and intracellular components and changes in motility pattern and metabolism of the gametogenesjs. In human, this increase occurs within 1 to 3 min of sperm-oocyte fusion and takes the form of a wave originating at the point of spermatozoon entry Reviewed in Ben-Yosef and Shalgi, By visiting this site you agree to the foregoing terms and conditions.


A schematic diagram of gametogenesis in mammals has been illustrated in Fig. This replenishment of spermatogonia means that males are fertile throughout their adult life. Interactions between somatic cells and germ cells throughtout mammalian oogenesis.

There are a series of stages: Growth and development of the mammalian oocyte. Embryo Transfer in Farm Animals: Effect of follicle size on bovine oocyte quality and developmental competence following maturation, fertilization and culture in vitro. Anatomy and physiology of pre-attachment bovine embryos. The embryo undergoes polarization and differences arise between the blastomeres as cleavage stage progresses.

The age of puberty for female goat or doe is ranged between vevetal and 7 months Jainudeen et al.

Useful Notes on Gametogenesis (Spermatogenesis and Oogenesis)

This process is referred to as cleavage Hafez and Hafez, b. Maternal RNA content in oocytes of several marnmalian and avian species.

But the cytoplasmic specialization in oogenesis is different from spermatogenesis. The primary germ cells multiply by repeated mitotic division. Capacitation mechanisms and the role of capacitation as seen in eutherian mammals. The cytoplasmic growth is associated with increase in number of mitochondria, endoplasmic reticulum and Golgi complex and accumulation of reserve food material called yolk or vitellin.

Developmental competence of goat oocytes from follicles of different size categories following maturation, fertilization and culture in vitro.