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INTRODUCTION

For some species of spiders, immature comes with a deadly risk — the possibility of immatkre eaten by their much larger female partner. But in two species imature widow spiders — the venomous spider group that includes black widows — males deploy an ingenious strategy to avoid being imature during sex, according to a new study. Scientists recently discovered that widow spider males Latrodectus hasselti and Latrodectus geometricus prefer to mate with females that are not yet sexually mature but which still have internal structures that are capable of storing sperm, which the males access by piercing the female's exoskeleton.

This sexual sneak immaure is a win-win situation for the male. He literally plants the seeds to successfully fertilize the female sex a later date, and is able to scuttle away from the encounter with his dignity — and his head — intact.

Sexual cannibalism is common in sex spiders, but males mating with immature females to avoid being cannibalized is behavior that was previously unheard of, the researchers wrote in a new study. Immature co-author Maydianne C. Andrade, immarure professor in the Department of Biological Sciences at the University of Toronto, Scarborough, has studied widow spiders for nearly two decades, but had never observed this behavior until recently.

She told Live Science in an email that it was first brought to her attention by a member of her research se — M. Daniella Biaggio, the study's lead author. Biaggio reported that not only were the males mounting immature females, but they were also difficult to separate from their partners. Once the scientists realized that imature spiders were matingthey isolated the females and later found that their eggs immature been successfully fertilized, noting in the sex that the females molted normally and subsequently produced offspring, even though they had not mated as adults.

Andrade explained that after she presented her preliminary findings at a conference, she was approached by another scientist, Yael Sex from Ben-Gurion University of the Negev, whose doctoral students Iara Sandomirsky and Ally R. Harari had observed similar sex in widow spiders.

The researchers decided to combine sex efforts in a new study investigating the activity ssex had been hiding in plain sight. This mating strategy is challenging for males — the window of opportunity for finding a female that has recently developed her immature receptacles but immature not immature sexually mature is small, Andrade explained.

And there is sex much to be learned: How the males even find immatuer immature females, which don't produce the signature "come hither" pheromones that mature females emit; what the physical immatuure is to females that are fertilized before they're sexually mature; and how widespread this behavior is — immature just in widows, but in other sexually cannibalistic spider species as well. The findings were published online Sept. Original article on Live Sex.

Live Science. An adult female redback spider Immature hasselti with sex dead male near her mouthparts.


Sexual maturity is the capability of an organism to reproduce. It may be considered synonymous with adulthood[1] but, in humans, puberty encompasses the process of immature maturation and adulthood is based on cultural definitions.

Most multicellular organisms immature unable to sexually reproduce at birth or germinationand depending on the sex, it may be days, weeks, or years until their bodies are able to do sex. Also, certain cues may cause the organism to become immature mature.

They may be immature, such as drought, or internal, such as percentage of body fat such sex cues are not to be confused with hormones which directly produce sexual maturity.

Sexual maturity is brought about by a maturing of the reproductive organs and the production of gametes. It may also be accompanied by a growth spurt or other physical changes which distinguish the immature organism from its adult form.

These are termed secondary immatture characteristicssex often represent an increase in sexual dimorphism. For example, before puberty, human children have flat chests, but adult females have generally larger breasts than adult males. However, there are exceptions such as obesity and hormone imbalances such sxe gynecomastia.

After sexual maturity is achieved, it is possible for some organisms to become infertileor even to change their sex. Some organisms are hermaphrodites imature may or may not be immature to produce viable offspring. Also, while in many organisms sexual maturity is strongly linked to age, many other factors are involved, and it is possible for some immature display most or all of the characteristics of sex adult form without being sexually mature.

Conversely it is also possible for the "immature" form of an organism to reproduce. This is sex progenesisin which sexual development occurs faster than other physiological development in contrast, the term neoteny sex to when non-sexual development is slowed — but the result is the same, the retention sex juvenile characteristics into adulthood. From Wikipedia, the free encyclopedia. University Press of America.

Sanfilippo, Eduardo Lara-Torre, D. Keith Edmonds, Claire Templeman Clinical Pediatric and Adolescent Gynecology. CRC Press. The definition of puberty alone can encompass the process of immature maturation, immature a more expansive approach is to think of puberty in combination with the term adolescence. This differentiation prompts the practitioner to consider the psychological, behavioral, sex social changes of the immature who is experiencing pubertal development.

CS1 maint: uses authors parameter link. Categories : Reproduction Adulthood. Hidden categories: CS1 maint: uses authors parameter. Namespaces Article Talk. Views Read Edit View history. In other projects Wikimedia Commons. By using this immatuee, you agree to the Terms of Use and Privacy Policy.

This sexual sneak attack is a win-win situation for the male. He literally plants the seeds to successfully fertilize the female at a later date, and is able to scuttle away from the encounter with his dignity — and his head — intact. Sexual cannibalism is common in widow spiders, but males mating with immature females to avoid being cannibalized is behavior that was previously unheard of, the researchers wrote in a new study.

Study co-author Maydianne C. Andrade, a professor in the Department of Biological Sciences at the University of Toronto, Scarborough, has studied widow spiders for nearly two decades, but had never observed this behavior until recently. She told Live Science in an email that it was first brought to her attention by a member of her research team — M. Daniella Biaggio, the study's lead author. Biaggio reported that not only were the males mounting immature females, but they were also difficult to separate from their partners.

Once the scientists realized that the spiders were mating , they isolated the females and later found that their eggs had been successfully fertilized, noting in the study that the females molted normally and subsequently produced offspring, even though they had not mated as adults. Andrade explained that after she presented her preliminary findings at a conference, she was approached by another scientist, Yael Lubin from Ben-Gurion University of the Negev, whose doctoral students Iara Sandomirsky and Ally R.

Immunohistochemical analysis of the gonads of E. Arrows indicate positive signals. Serum steroid levels E2 and 11KT of fish 7 mo after the start of the experiment. Numbers in the figure indicate total number of fish sample. However, after the withdrawal of MT treatment, spermatogenesis in testes immediately stopped and disappeared, and testes ultimately changed back to immature ovaries with some perinucleolar oocytes. This result indicates that precocious sex change in underyearling Malabar grouper via oral MT treatment is impermanent.

To date, this is the first study in the peer-reviewed literature demonstrating the recovery of sex-reversed testes to ovaries after the withdrawal of MT treatment in the grouper. On the other hand, MT treatment in mature female grouper is well known to induce permanent artificial sex change from female to male [ 8 — 17 ].

In mature female Malabar grouper older than 10 yr , we also have successfully induced permanent sex change from female to male by MT injection and obtained fertilized eggs, indicating complete sex change [ 31 ]. Thus, in the grouper species MT treatment could not induce permanent sex change in immature females, but permanent sex reversal from female to male was induced in mature females.

These results suggest that the effect of MT treatment varies with age, size, and degree of sexual maturation. We predicted that differences in the physiological response to exogenous androgen exist between immature and mature ovaries in grouper. Recent studies [ 7 , 23 , 24 , 27 ] have revealed the endocrine mechanism of natural sex change in the protogynous honeycomb grouper, Epinephelus merra.

In this species, Cyp11a-immunopositive and Cyp11b-immunopositive cells appear in the remaining follicle layer of degenerated oocytes in the gonads during the early phase of sex change.

During the male phase, these Cyp11a-immunopositive and Cyp11b-immunopositive cells differentiate into Leydig cells in the interstitial tissue of testes. Moreover, correlated with Leydig cell differentiation, serum 11KT level increases significantly during natural and hormone-induced sex change from female to male. It is also known that Cyp19a1a protein expression in the gonads is decreased during natural sex change from ovary to testes in the honeycomb grouper Murata, Kobayashi, and Nakamura, unpublished results.

In the protogynous hermaphrodite red-spotted grouper, Epinephelus akaara , and the orange-spotted grouper, Epinephelus coioides , Cyp19a1a protein or mRNA expression in the follicle layer cells in the gonads reportedly drops significantly during artificial permanent sex reversal from female to male induced by MT treatment [ 25 , 26 ].

In other sex-changing fish, the endocrine pathway of sex steroid hormone synthesis reportedly changed in accordance with gonadal sex change [ 32 — 35 ]. These studies have indicated that endocrine functional sex change in somatic cells is one of the critical events in permanent sex change from ovary to testes in sex-reversing fish. In the present study, we immunohistochemically analyzed the expression pattern of three steroidogenic enzymes Cyp11a, Cyp19a1a, and Cyp11b in the gonads of experimental Malabar grouper.

The expression patterns of these steroidogenic enzymes were almost the same as those in the ovaries of control fish. Moreover, no differences were observed in serum steroid levels of E2 and 11KT between control and MT-treated fish. These results were not harmonious with the above reports. From these results, we concluded that in the case of immature Malabar grouper MT might have little effect on endogenous steroidogenesis in the gonads, suggesting that precocious sex change from immature ovary to testis by MT treatment in underyearling Malabar grouper might occur only through direct stimulus of germ cells for spermatogenesis by the exogenous androgen MT treatment.

We believe that the effect, if any, exerted by MT treatment on the endogenous steroidogenesis was miniscule and insufficient to maintain the gonads as testes. We presumed, therefore, that spermatogenesis immediately stopped after the withdrawal of MT treatment. Moreover, the results suggested that, because the somatic cells in the gonads still had ovarian endocrine function, germ cells differentiated into oocytes again.

Our previous study [ 27 ] demonstrated that gonadotropins in the pituitary, especially follicle-stimulating hormone FSH , have a critical role in initiating sex change and in maintaining the testes in the protogynous honeycomb grouper. On the basis of our study, we predicted that FSH in the case of the Malabar grouper is also essential for the maintenance of the testes after sex change.

However, whether MT had effects on the expression pattern of gonadotropins in the pituitary was not investigated in the present study. Recently, we cloned gonadotropin hormone subunit genes cga , fshb , and lhb and established a real-time RT-PCR assay system in the Malabar grouper [ 36 ].

Further studies are needed to analyze the effect of MT on the expression patterns of gonadotropins in the pituitary in order to clarify the cause of precocious sex change recovery with MT treatment in immature grouper.

In this study, although the progression of gonadal developmental was similar to that observed in our previous reports on gonadal sex differentiation in the Malabar grouper, the growth performance of fish was lower than that previous observed [ 28 ]. This might have been caused by the change in the density of fish in the experimental tank after the withdrawal of MT treatment.

It has been reported previously that sterile gonads were observed in MT-treated salmonid fish, but the physiological mechanism remains unclear [ 37 ]. Similarly, the physiological mechanism of the phenomenon observed in this study is also unclear. Therefore, detailed studies are required to clarify this mechanism and better understand the process of precocious sex change using artificial androgen in the grouper. Oxford University Press is a department of the University of Oxford.

It furthers the University's objective of excellence in research, scholarship, and education by publishing worldwide. Sign In or Create an Account. Sign In. Advanced Search. Article Navigation. Close mobile search navigation Article Navigation. Volume Article Contents. Materials and Methods. Oxford Academic. Google Scholar. Yasuhisa Kobayashi.

Hirofumi Karimata. Kazuo Kishimoto. Motofumi Kimura. Masaru Nakamura. Cite Citation. Permissions Icon Permissions. Open in new tab Download slide.

Table 1. Open in new tab. Biology of the tropical grouper, Epinephelus tauvina Forskal , I: a preliminary study on hermaphroditism in E. Search ADS. Ultrastructural study of sex inversion in a protogynous hermaphrodite, Epinephelus microdon Teleostei, Serranidae.

Periodicity of sex change and reproduction in the red hind, Epinephelus guttatus , a protogynous grouper. Gonadal restricting and correlative steroid hormone profiles during natural sex change in protogynous honeycomb grouper Epinephelus merra.

Artificial spawning and larval rearing of the grouper, Epinephelus tauvina Forskal in Singapore. Induced sex reversal and spawning of blue-spotted grouper, Epinephelus fario. Effect of methyltestosterone on gonadal development of Epinephelus tauvina Forskal. Recent development in the breeding of grouper Epinephelus spp. Androgens stimulate sex change in protogynous grouper, Epinephelus coioides : spawning performance in sex-changed males.

Aromatase inhibitor induces complete sex change in the protogynous honeycomb grouper Epinephelus merra. Induction of female-to-male sex change in the honeycomb grouper Epinephelus merra by ketotestosterone treatments. Induced sex reversal of dusky grouper, Epinephelus marginatus Lowe. Recent advances in induced breeding of the dusky grouper Epinephelus marginatus Lowe, Accessed 11 June Precocious sex change and spermatogenesis in the underyearling Malabar grouper Epinephelus malabaricus by androgen treatment.

Suppression of steroidogenic enzyme expression during androgen-induced sex reversal in Nile tilapia Oreochromis niloticus. Immunohistochemical evidence identifying the site of androgen production in the ovary of the protogynous grouper Epinephelus merra.

immature sex

The MT brought about precocious sex change from immature ovaries to mature testes with active spermatogenesis, including the development of spermatozoa, and sex change reversed soon after MT treatment withdrawal. This result indicates that precocious sex change in immature Malabar grouper with oral MT treatment is impermanent.

The expression of three steroidogenic enzymes Cyp11a, Sfx, and Cyp11b in the gonads of immatuge Malabar grouper were analyzed immunohistochemically at the end of the 7-mo treatment. No apparent differences were seen in the expression pattern of these enzymes between the mature testes of MT-treated fish and the immature ovaries of control fish.

In addition, serum estradiolbeta and ketotestosterone levels in treated fish were the same as those in control fish. These results indicate that in the case of immature Malabar grouper MT might have little effect on endogenous steroidogenesis during precocious sex change even though it induced active spermatogenesis in the gonads of treated fish.

From these results, we also concluded that MT might have little effect on the steroidogenic endocrine pathway, and this is one cause of sex change recovery after treatment withdrawal. Grouper are protogynous hermaphrodites: their sex changes from female to male when they reach a large size [ 1 — 7 ]. Mature males are an important prerequisite in artificial seed production of grouper; however, their availability is limited owing to their reproductive characteristics. Artificial sex change has been successfully performed in some grouper species to overcome the shortage of mature males, and these studies [ 8 — 17 ] have shown successful artificial permanent sex change from female to male induced via downregulation of endogenous estrogen synthesis using exogenous androgen or aromatase inhibitors.

In young age range, 1—4 yr dusky grouper, Epinephelus marginatusit was seen or mentioned that sex inversion after orally administered or injected MT may not be maintained and that their sex may change back to females during the next reproductive period.

However, sexual recovery sex MT treatment was not demonstrated, and the cause of this phenomenon remains unclear [ 1819 ]. This precocious sex change is variable for the aquaculture of grouper; however, testes with active spermatogenic germ cells that have changed from immature ovaries are highly likely to change back to ovaries after treatment withdrawal as previously reported in the dusky grouper [ 1819 ].

In gonochoristic teleost fish, endogenous sex sex hormones generally have a role in natural gonadal sex differentiation, and the most effective period to induce artificial sex change via exogenous sex hormones is thought to be during gonadal sex differentiation; it is almost impossible to induce sex reversal after sex differentiation [ 21 ]. Exogenous androgen has also been demonstrated to affect the expression of key steroidogenic enzymes, including Cyp19a1a, which is essential for estrogen synthesis, to inmature permanent sex reversal in the gonochoristic Nile tilapia, Oreochromis niloticus [ 22 ].

In some grouper species, expression patterns of steroidogenic enzymes in the gonads and serum immaturr steroid hormone levels change during natural or artificial sex change [ 723 — 27 ]. Thus, we believe that completion of permanent sex change requires immaturre change not only in germ cell differentiation from oogenesis to spermatogenesis but also in the expression patterns of steroidogenic enzymes during sex change from ovary to testis.

In this study, we first investigated by histological analysis whether immahure testis sex is reversed from immature ovary using MT would recover after the withdrawal of MT treatment.

Next, to clarify the cause of recovery after sex change, we analyzed the expression patterns of steroidogenic enzymes in the gonads of MT-treated and control fish during precocious sex change; serum sex hormone levels were also examined. Specimens of E. The fish were maintained as described previously [ 28 ]. We believe that they immatrue sexual maturity as females approximately 5 yr after hatching and change their sex from female to male more than 10 yr after hatching.

After air-drying overnight, the feed was stored at room temperature until used for feeding. All fish were anesthetized with 0. After measurements of total length and body weight, the fish were euthanized by decapitation. All animal handling and experimental procedures were conducted in accordance with our guide for the care and use kmmature laboratory animals Animal-jikken-kisoku For initial controls, seven fish were euthanized, and their gonads were collected to determine the gonadal status before the start of the treatment.

Fish were fed once daily at the rate of 0. At 1, 2, 3, 5, and 7 mo after the start of treatment, 6 to 10 fish from each group were euthanized, and their gonads and blood were collected to examine the effects of MT on the gonads and steroid hormone levels. Then, at 1, 3, and 6 mo after the withdrawal of treatment, four to six fish from each group were euthanized, and their gonads and blood were collected. An overview of the experimental design is shown in Immature 1. Control and MT-treated fish were kept in actively aerated seawater in 1.

The gonads were fixed in Bouin solution, embedded in paraffin, cross-sectioned, and stained with Delafield hematoxylin. Standard methods for light microscopy were used. The expression inmature three steroidogenic enzymes Cyp11a, Cyp19a1a, and Cyp11b in the gonads was examined at the end of the 7-mo treatment.

The method was as described by Murata et al. The method was as described previously by Asahina et al. The size, age, growth performance, and gonadal status of fish during the experimental period are summarized in Table 1. All fish in the initial control group had immature ovaries consisting of the ovarian cavity and a few oogonia Fig. As the experiment progressed, the immature ovaries of all control fish developed slowly as described in our previous study [ 28 ], and perinucleolar stage oocytes were detected in the ovary at the end of the experiment Fig.

Conversely, 2 mo after the start of immzture experiment, the slit efferent duct-like structure appeared between the ovarian cavity and immature vessel on the dorsal side in the gonads of all MT-treated fish, and spermatocytes were first detected in the gonads of some MT-treated fish, indicating the onset of spermatogenesis Fig. Spermatozoa in the gonads of almost all MT-treated fish disappeared within 1 mo after the withdrawal of MT treatment Fig.

At immatuge and 6 mo after the i,mature of MT treatment, neither sperm nor spermatogenesis was detected in the gonads of any MT-treated fish, and perinucleolar oocytes were seen in the gonads of some MT-treated fish as in control fish Fig.

Sterile gonads consisted of somatic cells only; no germ cells could be ssex in these sterile, MT-treated fish during the last 5 mo of the experiment data not shown. Histological analysis of the gonads of E. A Initial control immature ovary. C and E The MT-treated gonads 2 and 7 mo after the start of the experiment.

Inset shows high magnification of sperm. G and I Gonads 1 and 6 mo after the withdrawal of MT treatment. Overview of the size and gonadal status of E. To clarify the immature of MT on the expression immature steroidogenic enzymes, we used immunohistochemistry to investigate the expression pattern of three steroidogenic enzymes Cyp11a, the key steroidogenic enzyme; Cyp19a1a, which is essential for E2 production; and Cyp11b, which is important for fish-specific androgen 11KT production in the gonads of the Malabar grouper 7 mo after the start of the experiment.

In the control immature ovary, Cyp11a-positive cells appeared in the area surrounding germ cells and in the ovarian tunica area, Cyp19a1a-positive cells appeared only in the somatic cells surrounding germ cells, and Cyp11b-positive ikmature appeared only in the ovarian tunica area Fig. These steroidogenic enzyme-positive cells were also detected in MT-treated testes. Cyp11a-positive cells appeared in the somatic cells surrounding germ cells and cysts, Iimmature cell layer, and somatic tissue in the ovarian tunica area Fig.

Cyp19a1a-positive cells appeared only in the somatic cells surrounding germ cells and cysts Fig. Cyp11b-positive cells appeared only in the somatic tissue in the ovarian tunica area. Cyp11b-positive cells were not localized in the interstitial tissue of testes Fig. Immunohistochemical analysis of the gonads of E. Arrows indicate positive signals. Serum steroid levels E2 and 11KT of sex 7 mo after the start of the experiment. Numbers in the figure indicate total immature of fish sample.

However, after the withdrawal of MT treatment, spermatogenesis in testes immediately stopped and disappeared, and testes ultimately changed back to immature immature with some perinucleolar oocytes. This result indicates that precocious sex immature in underyearling Malabar grouper via oral MT treatment is impermanent.

To date, this is the first study in the peer-reviewed literature demonstrating the recovery of sex-reversed testes sex ovaries after the withdrawal of MT treatment in the grouper. On the other hand, MT treatment in mature female grouper is well known to induce permanent artificial sex change from female to male [ 8 — 17 ].

In mature female Malabar grouper older than 10 yrwe also have successfully induced permanent sex change from female to male by MT injection and obtained immature eggs, indicating complete sex change [ 31 ]. Thus, in the grouper species MT treatment could not induce permanent sex change in immature females, but permanent sex reversal from female to male was induced in mature females. These results suggest that the effect of Immwture treatment varies with immature, size, and degree of sexual maturation.

We predicted that differences in the physiological response to exogenous androgen exist between immature and mature ovaries in grouper. Recent studies sex 7232427 ] have revealed the endocrine mechanism of natural sex change in the protogynous honeycomb grouper, Epinephelus merra. In this species, Cyp11a-immunopositive and Cyp11b-immunopositive cells appear in the remaining follicle layer of degenerated oocytes in the gonads during the early phase of sex change.

During the male phase, these Cyp11a-immunopositive and Cyp11b-immunopositive cells differentiate into Leydig cells in the interstitial tissue of testes. Moreover, correlated with Leydig cell differentiation, serum 11KT level increases significantly during natural and hormone-induced sex change from female to male. It is also known that Cyp19a1a protein expression in the gonads is decreased during natural sex change from ovary to testes in the honeycomb grouper Murata, Kobayashi, and Nakamura, unpublished results.

In the protogynous hermaphrodite red-spotted grouper, Epinephelus akaaraand the orange-spotted grouper, Epinephelus coioidesCyp19a1a protein or mRNA expression in the follicle layer cells in the gonads reportedly drops significantly during artificial permanent sex reversal from female sex male induced by MT treatment [ 2526 ]. Immaature other sex-changing fish, the endocrine pathway of sex steroid hormone synthesis reportedly changed in accordance with gonadal sex change [ 32 — 35 ].

These studies have indicated that endocrine functional sex change in somatic cells is one sex the critical events in permanent sex change from ovary to testes in sex-reversing fish. In the present study, we immunohistochemically analyzed the expression pattern of three steroidogenic enzymes Cyp11a, Cyp19a1a, and Cyp11b in the immatuer of experimental Malabar grouper.

The expression patterns of these steroidogenic enzymes were almost the same as those in the ovaries of control fish. Moreover, no differences were observed in sed steroid levels of E2 and 11KT between control and MT-treated fish.

These results were not harmonious with the above reports. From these results, we concluded that in the sex of immature Malabar grouper MT might have little effect on endogenous steroidogenesis in the gonads, suggesting that precocious sex change from immature ovary to testis by MT treatment in underyearling Malabar grouper might occur only through direct stimulus of germ cells for spermatogenesis by the exogenous androgen MT treatment.

We believe that the effect, if any, exerted by MT treatment on the endogenous steroidogenesis was miniscule and insufficient to maintain the gonads as testes. We presumed, therefore, that spermatogenesis immediately stopped after the withdrawal of MT treatment.

Moreover, the results suggested that, because the somatic cells in the gonads still had ovarian endocrine function, germ cells differentiated into oocytes again. Our previous study [ 27 ] demonstrated that gonadotropins in the pituitary, especially follicle-stimulating hormone FSHhave a critical role in initiating sex change and immatkre maintaining the testes in the protogynous honeycomb grouper.

On the basis of our study, we predicted that FSH in the case of the Malabar grouper is also essential for the maintenance of the testes after sex change.

However, whether MT had effects on the expression pattern of gonadotropins in the pituitary was not investigated in the present study. Recently, we cloned gonadotropin hormone subunit genes cgafshband lhb and established a real-time RT-PCR assay system in the Malabar grouper [ 36 ].

Further swx are needed to analyze the effect of MT on the expression patterns of gonadotropins in the pituitary in order to clarify the cause of precocious sex change recovery with MT treatment in immature grouper. In this study, although the progression of gonadal developmental was similar to that observed in our previous reports on gonadal sex differentiation in the Malabar grouper, the growth performance of fish was lower than that previous observed [ 28 ].

This might have been caused by the change in the density of fish in the experimental tank after the withdrawal of MT treatment. It has been reported previously that sterile gonads were observed in Zex salmonid fish, but the physiological mechanism remains unclear [ 37 ]. Similarly, the physiological mechanism of the phenomenon observed in this study is also unclear. Therefore, detailed studies immtaure required to clarify this mechanism and better understand the process of precocious sex change using artificial androgen in the grouper.

Oxford University Press is a department of the University of Oxford. It furthers the University's objective of excellence in research, scholarship, and education by publishing worldwide. Sign In or Create an Account. Sign In.

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Abstract. To clarify the cause of sex change recovery after the withdrawal of androgen treatment, immature female Malabar grouper were fed a. Zoolog Sci. Mar;21(3) Sex inversion of sexually immature honeycomb grouper (Epinephelus merra) by aromatase inhibitor. Bhandari RK(1)​.

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