Limites et améliorations du sexage des salmonidés par dosage de la 11-cétotestostérone circulante

1983 ◽  
Vol 61 (2) ◽  
pp. 457-460 ◽  
Author(s):  
P.-Y. Le Bail ◽  
A. Fostier ◽  
O. Marcuzzi
Keyword(s):  
Sex Determination ◽  
Organic Solvents ◽  
Sexual Development ◽  
Single Injection ◽  
Plasma Concentrations ◽  
Pituitary Extract

The use of plasma concentrations of 11-ketotestosterone for determining sex has been studied in various species of salmonids (O. kisutch, S. salar, S. gairdneri, S. trutta) at different stages of their sexual development. Radioimmunological titrations were performed; though they are less sensitive than filtrations with an extraction by organic solvents, they are quicker to use. The percentage of error in sex determination is low (5%) in animals that have developing gonads or that are still in prepuberty, but is much higher in immature animals. A single injection of total pituitary extract (equivalent to 100 ng of s-GtH per gram) will reduce this error to 2% by stimulating 11-ketotestosterone secretion.[Journal translation]

Changes in androgen concentrations during puberty and their relation to behaviour in male Saccostomus campestris (Gray 1844), an African rodent

1993 ◽  
Vol 5 (5) ◽  
pp. 577 ◽  
Author(s):  
LM Westlin ◽  
HM Dott
Keyword(s):  
Sexual Development ◽  
Plasma Concentrations ◽  
Reproductive Organs ◽  
Oestrous Cycle ◽  
Plasma Testosterone ◽  
Seminiferous Tubules ◽  
Morphological Development ◽  
Intraindividual Variation ◽  
Adult Females ◽  
Tubule Diameter

Sexual development in male Saccostomus campestris, the pouched mouse, was studied in terms of morphological development and changes in concentrations of plasma testosterone and androstenedione. The interaction of adult females and males following the introduction of a male was observed at all stages of the oestrous cycle. The histology of the reproductive organs is similar to that of other rodents. Measurements of the diameter of the seminiferous tubules and the width of the seminiferous epithelium suggest asymptotic growth but, although the diameter had not reached the asymptote at 70 days of age the epithelial width was close to the calculated asymptote at 55 days of age. Intraindividual variation was no greater than variation between individuals of the same age from 55-70 days. Spermatids were not seen in any animals younger than 45 days, but all animals over 55 days of age had spermatozoa in the epididymis. By 70 days of age, fertile matings were observed. At this stage, the seminiferous tubule diameter was still increasing slowly but plasma concentrations of testosterone and androstenedione had reached adult levels; at no time was the concentration of testosterone greater than androstenedione. The males were never aggressive towards females; however, they were severely attacked by females at all stages of the oestrous cycle except pro-oestrus. Only rarely did males show aggression to other males.

Concentrations of luteinizing hormone and progesterone in plasma during sexual development of the Khaki Campbell duck

1982 ◽  
Vol 93 (1) ◽  
pp. 47-53 ◽  
Author(s):  
Susan C. Wilson ◽  
T. R. Morris
Keyword(s):  
Plasma Concentration ◽  
Luteinizing Hormone ◽  
Negative Correlation ◽  
Sexual Development ◽  
Plasma Concentrations ◽  
Winter Solstice ◽  
Pronounced Increase ◽  
Threefold Increase ◽  
Lh Release

Concentrations of LH and progesterone were measured in the plasma of ducks which were, from 3 weeks of age, raised on either a constant photoperiod of 16 h light: 8 h darkness or a lighting schedule which simulated natural changes in daylength. In ducks raised on a constant photoperiod of 16 h light: 8 h darkness the plasma concentration of LH increased steeply between 7 and 3·5 weeks before the onset of lay. Concentrations of LH then declined, gradually at first, but then rapidly during the 7 days before the first oviposition in association with a pronounced increase in the plasma concentration of progesterone. During the 18 days before the first egg was laid there was a significant (P < 0·01) negative correlation between the plasma concentrations of LH and progesterone. The patterns of LH release during sexual development of ducks raised on a schedule which simulated natural changes in daylength were variable but could be categorized according to the daylength at which each duck came into lay. In ducks coming into lay soon after the winter solstice when daylength was short (8·0–8·5 h light/day) there was a pronounced 15-fold prepubertal increase in the plasma concentration of LH although in some ducks high LH levels were not maintained until 3–4 weeks before the first oviposition and were not always followed by a rise in the plasma concentration of progesterone. In contrast, in ducks coming into lay when daylength had increased to 11·0–11·5 h light/day there were only minor fluctuations in the plasma concentration of LH until a small two- to threefold increase in LH was observed during the 2 weeks before the first oviposition.

scholarly journals DNA Methylation Reprogramming during Sex Determination and Transition in Zebrafish

2020 ◽  
Author(s):  
Xinxin Wang ◽  
Xin Ma ◽  
Gaobo Wei ◽  
Weirui Ma ◽  
Zhen Zhang ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Sex Determination ◽  
Sexual Development ◽  
Epigenetic Modification ◽  
Sex Differentiation ◽  
Primordial Germ Cells ◽  
Regulation Of Gene Expression ◽  
Adult Zebrafish ◽  
Germline Development ◽  
Male Sex

AbstractIt is a mystery about sex determination and sexual plasticity in species without sex chromosomes. DNA methylation is a prevalent epigenetic modification in vertebrates, which has been shown to involve in the regulation of gene expression and embryo development. However, it remains unclear about how DNA methylation regulates sexual development. To elucidate it, we used zebrafish to investigate DNA methylation reprogramming during juvenile germ cell development and adult female-to-male sex transition. We revealed that primordial germ cells (PGCs) undergo significant DNA methylation reprogramming during germline development and set to an oocyte/ovary-like pattern at 9 days post fertilization (9 dpf). When blocking DNMTs activity in juveniles after 9 dpf, the zebrafish preferably develops into females. We also show that Tet3 involves in PGC development. Notably, we find that DNA methylome reprogramming during adult zebrafish sex transition is similar to the reprogramming during the sex differentiation from 9 dpf PGCs to sperm. Furthermore, inhibiting DNMTs activity can prevent the female-to-male sex transition, suggesting that methylation reprogramming is required for zebrafish sex transition. In summary, DNA methylation plays important roles in zebrafish germline development and sexual plasticity.

scholarly journals Elucidation of the determinant for orchestration of solo unisexual cycle in an important human fungal pathogen

2019 ◽  
Author(s):  
Pengjie Hu ◽  
Huimin Liu ◽  
Lei Chen ◽  
Guang-Jun He ◽  
Xiuyun Tian ◽  
...  
Keyword(s):  
Sex Determination ◽  
Sexual Development ◽  
Fungal Pathogen ◽  
Model Organism ◽  
Sexual Cycle ◽  
Critical Determinant ◽  
Human Fungal Pathogen ◽  
Alternative Approach ◽  
Sexual Determination ◽  
Functional Profiling

AbstractIn fungi, the sex-determination program universally directs sexual development and syngamy (the fusion of gametes) that underlies pre-meiotic diploidization. However, the contribution of sex-determination to syngamy-independent sexual cycle, which requires autopolyploidization as an alternative approach to elevate ploidy before meiosis, remains unclear in fungi and other eukaryotes. The human fungal pathogen Cryptococcus neoformans, as a model organism for studying fungal sexual reproduction, can undergo syngamy-dependent bisexual and syngamy-independent solo unisexual reproduction, in which endoreplication is considered to enable pre-meiotic self-diploidization. Here, by characterizing a mutant lacking all the core sex-determination factors, we show that sex-determination plays a central role in bisexual syngamy but is not strictly required for unisexual development and self-diploidization. This implies an unknown circuit, rather than the sex-determination program, for specifically coordinating Cryptococcus unisexual cycle. We reveal that syngamy and self-diploidization are both governed by the Qsp1-directed paracrine system via two regulatory branches, Vea2 and Cqs2. Vea2 directs bisexual syngamy through the sex-determination program; conversely, Cqs2 is dispensable for bisexual syngamy but activates unisexual endoreplication. Through functional profiling of 41 transcription factors documented to regulate Cryptococcus sexual development, we reveal that only Cqs2 can drive and integrate all unisexual phases and ensure the production of meiospore progenies. Furthermore, ChIP-seq analysis together with genetic evaluation indicate that Cqs2 induces unisexual self-diploidization through its direct control of PUM1, whose expression is sufficient to drive autopolyploidization. Therefore, Cqs2 serves as the critical determinant that orchestrates Cryptococcus multistage unisexual cycle that does not strictly require the sexual-determination program.

Faster protein and ribosome synthesis in thyroxine-induced hypertrophy of rat heart

1985 ◽  
Vol 248 (3) ◽  
pp. C309-C319 ◽  
Author(s):  
D. Siehl ◽  
B. H. Chua ◽  
N. Lautensack-Belser ◽  
H. E. Morgan
Keyword(s):  
Protein Synthesis ◽  
Single Injection ◽  
Plasma Concentrations ◽  
Bicarbonate Buffer ◽  
Ribosomal Subunits ◽  
Ribosome Synthesis ◽  
And Control ◽  
Perfused Hearts

Rates of protein synthesis and degradation were measured in hearts from normal and thyroxine-injected rats that were perfused as working preparations with Krebs-Henseleit bicarbonate buffer containing 400 microU insulin/ml, 2 mM lactate, 10 mM glucose, and normal plasma concentrations of amino acids. Hearts were perfused after four daily injections (1 microgram/g body wt) of thyroxine. Protein synthesis was 24% greater in hypertrophying hearts compared with controls; ribosomal RNA content increased 25%. In addition, the proportion of total RNA in free ribosomal subunits in hypertrophying hearts was unchanged from perfused hearts of control rats and from unperfused normal hearts. These results indicated that increased protein synthetic machinery as monitored by content of ribosomes, rather than more efficient initiation or elongation of peptide chains, accounted for the faster rate of protein synthesis in hypertrophying hearts. Rates of protein degradation were the same in hearts from thyroxine-injected and control animals. When rates of ribosome production were measured in vitro at various times after a single injection of thyroxine in vivo, faster ribosome synthesis was detected within 8 h; no change in the rate of total protein synthesis occurred after a single injection of thyroxine. These studies indicated that accelerated ribosome formation was an early and quantitatively important factor in cardiac hypertrophy.

scholarly journals Multi-Tissue Transcriptome Analysis Identifies Key Sexual Development-Related Genes of the Ornate Spiny Lobster (Panulirus ornatus)

Genes ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 1150
Author(s):  
Tomer Ventura ◽  
Jennifer C. Chandler ◽  
Tuan V. Nguyen ◽  
Cameron J. Hyde ◽  
Abigail Elizur ◽  
...  
Keyword(s):  
Sex Determination ◽  
Sexual Development ◽  
Molecular Mechanisms ◽  
Sex Chromosome ◽  
Spiny Lobster ◽  
Homology Search ◽  
Previous Knowledge ◽  
Key Factors ◽  
Factors Associated ◽  
Sex Determination Mechanisms

Sexual development involves the successive and overlapping processes of sex determination, sexual differentiation, and ultimately sexual maturation, enabling animals to reproduce. This provides a mechanism for enriched genetic variation which enables populations to withstand ever-changing environments, selecting for adapted individuals and driving speciation. The molecular mechanisms of sexual development display a bewildering diversity, even in closely related taxa. Many sex determination mechanisms across animals include the key family of “doublesex- and male abnormal3-related transcription factors” (Dmrts). In a few exceptional species, a single Dmrt residing on a sex chromosome acts as the master sex regulator. In this study, we provide compelling evidence for this model of sex determination in the ornate spiny lobster Panulius ornatus, concurrent with recent reports in the eastern spiny lobster Sagmariasus verreauxi. Using a multi-tissue transcriptomic database established for P. ornatus, we screened for the key factors associated with sexual development (by homology search and using previous knowledge of these factors from related species), providing an in-depth understanding of sexual development in decapods. Further research has the potential to close significant gaps in our understanding of reproductive development in this ecologically and commercially significant order.

VARIATIONS IN STORED AND PLASMA CONCENTRATIONS OF ANDROGENS AND LUTEINIZING HORMONE DURING SEXUAL DEVELOPMENT IN THE COCKEREL

1977 ◽  
Vol 74 (3) ◽  
pp. 467-476 ◽  
Author(s):  
P. J. SHARP ◽  
J. CULBERT ◽  
J. W. WELLS
Keyword(s):  
Luteinizing Hormone ◽  
Pituitary Gland ◽  
Sexual Development ◽  
Rapid Growth ◽  
Plasma Concentrations ◽  
Body Growth ◽  
Initial Increase ◽  
Temporary Reduction ◽  
Testicular Growth ◽  
Rate Of Growth

SUMMARY The concentrations of luteinizing hormone (LH) and testosterone in the plasma and the stored levels of LH, testosterone and androstenedione were measured in cockerels aged 8–29 weeks. The onset of puberty occurred between 16 and 24 weeks of age, when the testes entered a phase of rapid growth and spermatogenesis was completed. The following sequence of endocrine events was found to be associated with the onset of puberty: a fall in the amount of androstenedione in the testes before any evidence of increased testicular growth; an increase in the total amount of LH in the pituitary gland as the testes started to enlarge; an increase in the total amount of testosterone in the testes and in the concentration of LH in the plasma; an increase in the concentration of testosterone in the plasma. An increase in the rate of growth of the comb and testes preceded a detectable increase in the levels of LH and testosterone in the plasma. The increase in the amount of testosterone in the plasma which occurred after the initial increase in the concentration of LH was associated with the final stages of spermatogenesis, a decrease in the rate of body growth and a temporary reduction in the amount of LH secreted.

Maturational changes in the LH response of domestic fowl to synthetic chicken LHRH-I and -II

1989 ◽  
Vol 123 (2) ◽  
pp. 311-318 ◽  
Author(s):  
S. C. Wilson ◽  
F. J. Cunningham ◽  
R. A. Chairil ◽  
R. T. Gladwell
Keyword(s):  
Plasma Concentration ◽  
Sexual Development ◽  
Plasma Concentrations ◽  
Egg Laying ◽  
Prolonged Action ◽  
Initial Rise ◽  
Lh Release ◽  
Higher Doses ◽  
Type Response ◽  
Sustained Increase

ABSTRACT Treatment of chickens at different stages of sexual development with a single i.v. injection of synthetic chicken LHRH (cLHRH)-I or -II stimulated a rise in the plasma concentration of LH within 1 min. The activity of cLHRH-II was 1·3- to 2·7-fold greater than that of cLHRH-I in sexually immature cockerels and hens as determined by the changes in the plasma concentration of LH during the 5 or 10 min after injection. This could be attributed to both a greater effectiveness of cLHRH-II to stimulate LH release and to a more prolonged action. Thus, LH concentrations in plasma were maximal within 1–2 min of injection of all doses of cLHRH-I but within 2–5 min of injection at the higher doses of cLHRH-II. The responsiveness of the pituitary gland to cLHRH-I and -II was substantially greater in the sexually immature cockerel than in the hen and diminished during sexual development of the hen. Coincident with the onset of egg laying, the characteristics of the LH response to cLHRH-II changed to consist of an initial rise during the first 2 min, followed by a more sustained increase with LH concentrations still rising 10 min after injection. In contrast, after injection with cLHRH-I, plasma concentrations of LH rose to a peak at 2 min and thereafter declined gradually. Treatment of the sexually immature hen with oestradiol, progesterone or a combination of both steroids did not enable the expression of a laying hen-type response to the injection of cLHRH-II. It would appear, therefore, that unidentified events associated with the final stages of sexual maturation bring about changes in the mechanism of action of cLHRH-II which differ from those of cLHRH-I. Journal of Endocrinology (1989) 123, 311–318

Sign in / Sign up

Export Citation Format

Share Document