scholarly journals Gradual, temperature-induced change of secondary sexual characteristics in Trichogramma pretiosum infected with parthenogenesis-inducing Wolbachia

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7567
Author(s):  
Su-fang Ning ◽  
Jin-cheng Zhou ◽  
Quan-quan Liu ◽  
Qian Zhao ◽  
Hui Dong
Keyword(s):  
High Temperature ◽  
Sexual Differentiation ◽  
External Genitalia ◽  
Intermediate Stage ◽  
External Morphology ◽  
Trichogramma Pretiosum ◽  
Secondary Sexual Characteristics ◽  
Sexual Characteristics ◽  
Male External Genitalia ◽  
Secondary Sexual

Intersex is an intermediate stage of sexual differentiation in insects. Determining intersex morphology and the cause of its production will aid in the understanding of the mechanism of sexual differentiation in insects. In this paper, Wolbachia-infected Trichogramma pretiosum (T. preW+) that shows thelytokous parthenogenesis were used as subjects. In order to determine the causes of the T. preW+ intersex and the influence of parental generation temperature on gradual changes in secondary masculinization in intersex offspring, we examined the occurrence of intersex offspring (F1 and F2 generation) after the parental generations were treated with high temperature (27, 29, 31, and 33 °C) and described the external morphology of the intersexes. The results showed that the T. preW+ parental generation temperature is positively correlated with the probability of intersex offspring. The probability of F1 intersex is significantly higher than that of F2 intersex in different high temperature. The degree of secondary masculinization in T. preW+ intersexes increases as parental generation temperature increases. In addition, our study first identified 11 intersex types in T. preW+ and found that the primary and secondary sexual characteristics showed a regular distribution. We also found that the D type and H type of intersex have the highest frequency of appearance. The external genitalia of most intersexes were female, and only three intersex types have male external genitalia. Conclusions were ultimately obtained: Wolbachia is a direct factor that causes the occurrence of intersexes, while high temperature is an indirect factor that determines the external morphology of intersexes. The effects of high temperature on T. preW+ intersexes is passed through the parental generation to offspring, and this maternal effect weakens as the number of generations increases. In T. preW+ intersex individuals, most exhibit female primary sexual characteristics, and secondary sexual characteristics exhibit signs of masculinization.

scholarly journals Nuclear androgen receptor regulates testes organization and oocyte maturation in zebrafish

2017 ◽  
Author(s):  
Camerron M. Crowder ◽  
Christopher S. Lassiter ◽  
Daniel A. Gorelick
Keyword(s):  
Androgen Receptor ◽  
Oocyte Maturation ◽  
Sexual Differentiation ◽  
Gonad Development ◽  
External Genitalia ◽  
Endocrine Function ◽  
Secondary Sexual Characteristics ◽  
Gonad Differentiation ◽  
Sexual Characteristics

ABSTRACTAndrogens act through the nuclear androgen receptor (AR) to regulate gonad differentiation and development. In mice, AR is required for spermatogenesis, testis development and formation of external genitalia in males and oocyte maturation in females. However, the extent to which these phenotypes are conserved in nonmammalian vertebrates is not well understood, because mutations in AR have not been generated in any other species. Here, we generate zebrafish with a mutation in the ar gene and examine the role of AR on sexual differentiation and gonad development. We find that zebrafish AR is not required for male sexual differentiation, since a portion of ar mutants develop a testis. However, we show that in zebrafish, as in mice, AR is required for the development of secondary sexual characteristics and for proper organization of the testis in males and for oocyte maturation in females. Additionally, we find that zebrafish ar mutant males have functional, mature sperm present in their testis, but are infertile due to an inability to release sperm. These findings suggest that AR is required for male sexual development and fertility, but not essential for sexual differentiation in zebrafish. The ar mutant we developed will be useful for modeling human endocrine function in zebrafish.

Comparative urogenital morphology and external sex determination in muskellunge, Esox masquinongy Mitchill

1989 ◽  
Vol 67 (4) ◽  
pp. 1053-1060 ◽  
Author(s):  
Bernard Lebeau ◽  
Gérard Pageau
Keyword(s):  
Ventral Surface ◽  
Northern Pike ◽  
Structural Basis ◽  
Simple Method ◽  
Esox Masquinongy ◽  
Secondary Sexual Characteristics ◽  
Sexual Characteristics ◽  
Spawning Behaviour ◽  
Accurate Indicator ◽  
Secondary Sexual

Primary and secondary sexual characteristics in northern pike, Esox lucius Linneaus, and muskellunge, Esox masquinongy Mitchill, differ markedly. Differences in the internal urogenital anatomy include the structure of the genital ducts and the angle they form with the ventral surface. Externally, the genital and urinary ducts open directly to the environment in northern pike, whereas in muskellunge they open into a muscular papilla and then through a urogenital pore. Differences in sexual dimorphism between the two closely related esocids constitute a structural basis to explain the known differences in spawning behaviour and reproductive success. Differences in secondary sexual characteristics explain why the methods developed by Demchenko or Casselman to externally sex pike are inapplicable to muskellunge. To develop and test two external sexing techniques for muskellunge, specimens were collected from two regions in Canada from 1980 to 1987. Examination of reproductive products obtained from stripping provided an accurate indicator of sex and sexual maturity, but demonstrated serious limitations. A simple method to sex muskellunge by examination of the external urogenital morphology is described for juveniles and adults. Dissection of fish revealed that with the urogenital examination technique we sexed juveniles with a success rate of 92–98%, and adults with 100% accuracy.

The effects of phthalate and nonylphenol exposure on body size and secondary sexual characteristics during puberty

2015 ◽  
Vol 218 (7) ◽  
pp. 603-615 ◽  
Author(s):  
Jia-Woei Hou ◽  
Ching-Ling Lin ◽  
Yen-An Tsai ◽  
Chia-Huang Chang ◽  
Kai-Wei Liao ◽  
...  
Keyword(s):  
Body Size ◽  
Secondary Sexual Characteristics ◽  
Sexual Characteristics ◽  
Secondary Sexual

scholarly journals Somatotypical features of the age dynamics of secondary sexual characteristics and functional parameters in city schoolchildren

2021 ◽  
pp. 113-118
Author(s):  
V. A. Melnik
Keyword(s):  
Blood Pressure ◽  
Body Type ◽  
Age Dynamics ◽  
Functional Parameters ◽  
Secondary Sexual Characteristics ◽  
Age Related ◽  
Sexual Characteristics ◽  
Age Range ◽  
Age Related Changes ◽  
Secondary Sexual

Objective: to assess the constitutional features of the age dynamics of secondary sexual characteristics and functional parameters of city schoolchildren in the age range of 7–17 years.Materials and methods. The objects of the study were schoolchildren aged 7–17. The stages of the expression of secondary sexual characteristics were determined visually according to the scheme by J.M. Tanner. The functional parameters of the examined schoolchildren were assessed using the methods of dynamometry, spirometry; blood pressure and heart rates, as well as the time of simple sensorimotor reactions were measured.Results. As a result of the performed studies, it has been found that representatives of the hypersomnic types are ahead of other types to reveal the first stages of secondary sexual characteristics. Schoolchildren with the leptosomic morphotypes due to higher rates of their development have reached the definitive stages by the same age as those with the hypersomnic variants. The intensity of age-related changes in functional parameters (strength qualities, circulatory and respiratory systems, nervous system) in the studied objects depends on their body type.Conclusion. The stage and rate of puberty, as well as the development of functional parameters in city schoolchildren depends on their somatotype.

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