Sexual Maturity in the Captive Male Bandicoot, Isoodon-Macrourus

1987 ◽  
Vol 35 (5) ◽  
pp. 433 ◽  
Author(s):  
RT Gemmell
Keyword(s):  
Sexual Maturation ◽  
Sexual Development ◽  
Sexual Maturity ◽  
Reproductive Tract ◽  
Mature Female ◽  
Plasma Testosterone ◽  
Scrotal Skin ◽  
Male Reproductive Tract ◽  
Reproductive Ability ◽  
Stage Of Development

Various morphological and physiological features were examined weekly in developing male bandicoots, each housed with a mature female, from birth through to the fathering of their first litter. The first peak of plasma testosterone greater than 2 ng ml-' in the male was observed at 179.8 � 6.8 d old (mean � SE; n = 17); sperm were first observed in the male reproductive tract at approximately 200 d old and this coincided with the pigmentation of the scrotal skin at 199.5 � 8.2 d (n= 10). The first litters were sired at 349.7 � 14.0 d (n=7). Male bandicoots reached sexual maturity approximately 100 d later than females. Pigmentation of the scrotum would appear to be a useful indicator of the stage of sexual development because it occurs at the stage of development when sperm first appear in the reproductive tract in the male bandicoot. Nevertheless, the appearance of sperm and scrotal pigment, both precede sexual maturation by at least 150 d and are not good indicators of reproductive ability in the male bandicoot.

A study of sexual development in ram lambs

1986 ◽  
Vol 43 (3) ◽  
pp. 459-468 ◽  
Author(s):  
F. M. S. Al-Nakib ◽  
G. A. Lodge ◽  
J. B. Owen
Keyword(s):  
Body Weight ◽  
Testosterone Level ◽  
Sexual Development ◽  
Sexual Maturity ◽  
Semen Quality ◽  
Plasma Testosterone ◽  
Artificial Rearing ◽  
Sexual Characteristics ◽  
Ram Lambs ◽  
Mating Performance

ABSTRACTTwo experiments were designed to study the effect of rearing method, female company, and repeated libido and semen tests on the pattern of sexual development of ram lambs. Four artificial rearing treatments (AR) were compared with natural rearing (NR) in one experiment and four artificial compared with three natural rearing treatments in a second experiment. Lambs on AR treatments in both experiments, as well as naturally reared lambs in the second experiment, were reared with or without females either before and/or after weaning. Half the lambs in the second experiment were libido and semen tested, and their mean plasma testosterone level was also measured, while the rest were only tested at the end of the experiment. The effect of method of rearing and female company on body growth, testes diameter, libido and semen quality were also investigated.A close relationship was found between body weight and sexual characteristics (for example, testis diameter, semen traits, libido, testosterone level and age at the onset of sexual maturity). NR resulted in faster growth than AR but was not appreciably different from early weaned-naturally reared treatments. It was also observed that mating performance improved steadily with advancement in age and increase in body weight. The onset of sexual maturity was attained at a minimum of 23 kg body weight and a minimum of 198 days of age. However, the heavier the lamb when sexually mature, the better its mating performance.Previous libido tests of ram lambs improved their subsequent mating performance, but had no effect on semen quality. However, libido tests did not improve the performance of those ram lambs which did not exhibit initial libido.It is suggested that early weaning at 2 months of age could be a suitable system for ram lambs weaned off their mothers for breeding purposes. These lambs should be reared as an all-male group but libido tested at monthly intervals commencing at 3 months of age. The criteria for selecting these lambs at an earlier age should be body weight and testis diameter.

scholarly journals Gene expression and immunolocalization of low-affinity neurotrophin receptor (p75) in rabbit male reproductive tract during sexual maturation

2018 ◽  
Vol 53 ◽  
pp. 62-65 ◽  
Author(s):  
Ana Sanchez-Rodriguez ◽  
Maria Arias-Alvarez ◽  
Pilar G. Rebollar ◽  
Jose M. Bautista ◽  
Pedro L. Lorenzo ◽  
...  
Keyword(s):  
Gene Expression ◽  
Sexual Maturation ◽  
Reproductive Tract ◽  
Neurotrophin Receptor ◽  
Male Reproductive Tract

Prospects for hormonal contraception in the male

2000 ◽  
Vol 8 (2) ◽  
pp. 127-142
Author(s):  
RA Anderson
Keyword(s):  
Reproductive Tract ◽  
Hormonal Contraception ◽  
Seminiferous Tubules ◽  
Male Reproductive Tract ◽  
Scientific Advance ◽  
Testicular Spermatozoa ◽  
Stage Of Development ◽  
The Subject ◽  
Potential Methods ◽  
Developed World

Female-dependent methods of contraception have been the subject of considerable scientific advance since the introduction of the combined contraceptive pill, offering effective and male-independent contraception, but there is an emerging emphasis that men should be more involved in family planning. The supremacy of modern, female methods in the developed world obscures the fact that one-third of all couples worldwide rely on a male-dependent method of contraception, mostly the condom or withdrawal, methods that have been used since antiquity. Potential methods of male contraception include withdrawal of the gonadotrophic support to the testis, interference with spermatogenesis within the seminiferous tubules, or with post-testicular functions. Effects on maturation within the epididymis can be induced by chloro-6-deoxy sugars or plant-derived glycosides. Although advances in assisted conception, particularly associated with intracytoplasmic sperm injection (ICSI), have demonstrated the functional competence of the nucleus and centriole of testicular spermatozoa and other less mature forms, it has been suggested that normal passage through the male reproductive tract is necessary for conventional conception. Advances in both testicular and post-testicular methods of contraception have been hampered by toxicity and remain in preclinical testing, reflecting the limited extent of (and thus the need for) scientific knowledge in this area. While progress in these areas is fully acknowledged, the pretesticular hormonal approach is currently at a considerably more advanced stage of development with prospects for a real product becoming increasingly likely on a realistic time-scale. This review will therefore confine itself to this, the hormonal approach.

Localization of COX-2 in the male reproductive tract during sexual maturation

2003 ◽  
Vol 11 (3) ◽  
pp. 259-266 ◽  
Author(s):  
Kristina M. Stanfield ◽  
K. Nasir M. Khan
Keyword(s):  
Sexual Maturation ◽  
Reproductive Tract ◽  
Male Reproductive Tract ◽  
Cox 2

scholarly journals Structural Changes in the Male Reproductive Tract of the Stingless Bee Scaptotrigona xanthotricha Moure 1950 (Meliponini, Apidae) During Sexual Maturation

Sociobiology ◽  
2020 ◽  
Vol 67 (4) ◽  
pp. 526
Author(s):  
Vinícius Albano Araujo ◽  
José Eduardo Serrão ◽  
Yasmine Antonini ◽  
Lucimar Gomes Dias ◽  
José Lino Neto
Keyword(s):  
Reproductive Biology ◽  
Sexual Maturation ◽  
Reproductive Tract ◽  
Morphological Changes ◽  
Ejaculatory Duct ◽  
Seminal Vesicles ◽  
Stingless Bee ◽  
Basal Region ◽  
Male Reproductive Tract ◽  
Old Adults

Stingless bees are social insects widely distributed in the Neotropical region but the loss of habitats and the increased use of pesticides in agriculture have threatened the bee populations. Thus, the knowledge of the biology of these insects, including reproductive biology is important for their conservation and management. This study describes the morphological changes in the male reproductive tract during the sexual maturation in the stingless bee Scaptotrigona xanthotricha (Moure 1950). The reproductive tract was investigated under light microscopy from young pupae to 22 days old adults. The male reproductive organs in S. xanthotricha are a pair of testes, each with four follicles, pair of vasa deferentia with enlarged region forming the seminal vesicle that open in an ejaculatory duct. In the male reproductive system of these bees there is no structure that can be recognized as accessory glands as seen in insects in general. From brown-eyed pupae to newly-emerged adults, the epithelia of the seminal vesicles and post-vesicular vasa deferentia have prismatic cells that release secretion to the organs lumen. In 5-days old adults the testes undergo degeneration, the seminal vesicles filled with secretion and spermatozoa, and the epithelium has cubic cells rich in inclusions in the basal region suggesting that this is the age in which males reach the sexual maturation. Structural modifications in the reproductive tract during sexual maturation are discussed concerning the reproductive biology of Meliponini.

The Effect of PDE5 Inhibitors on the Male Reproductive Tract

2020 ◽  
Vol 26 ◽  
Author(s):  
Nikolaos Sofikitis ◽  
Aris Kaltsas ◽  
Fotios Dimitriadis ◽  
Jens Rassweiler ◽  
Nikolaos Grivas ◽  
...  
Keyword(s):  
Male Infertility ◽  
Reproductive Tract ◽  
Tunica Albuginea ◽  
Scientific Data ◽  
Secretory Function ◽  
Pde5 Inhibitors ◽  
Male Reproductive Tract ◽  
Review Study ◽  
Phosphodiesterase 5

The therapeutic range of cyclic nucleotide phosphodiesterase 5 inhibitors (PDE5) inhibitors is getting wider in the last years. This review study focuses on the potential employment of PDE5 inhibitors as an adjunct tool for the therapeutic management of male infertility. The literature tends to suggest a beneficial effect of PDE5 inhibitors on Leydig and Sertoli cells secretory function. It also appears that PDE5 inhibitors play a role in the regulation of the contractility of the testicular tunica albuginea and the epididymis. Moreover scientific data suggest that PDE5 inhibitors enhance the prostatic secretory function leading to an improvement in sperm motility. Other studies additionally demonstrate a role of PDE5 inhibitors in the regulation of sperm capacitation process. Placebo-controlled, randomized, blind studies are necessary to unambiguously incorporate PDE5 inhibitors as an adjunct tool for the pharmaceutical treatment of semen disorders and male infertility.

Changes in the Male Reproductive Organs of the Dugong, Dugong dugon (Sirenia: Dugondidae) with Age and Reproductive Activity

1984 ◽  
Vol 32 (6) ◽  
pp. 721 ◽  
Author(s):  
H Marsh ◽  
GE Heinsohn ◽  
TD Glover
Keyword(s):  
Reproductive Tract ◽  
Prostate Gland ◽  
Reproductive Activity ◽  
Reproductive Organs ◽  
Seminal Vesicles ◽  
Growth Layer ◽  
Male Reproductive Tract ◽  
Qualitative And Quantitative ◽  
Quantitative Examination ◽  
Testicular Histology

The anatomy and histology of the male reproductive tract of the dugong (Dugong dugon) is described. Each testis and its adjacent epididymis lie immediately caudal to the corresponding kidney. The seminal vesicles are large but there is no discrete prostate gland and the bulbo-urethral glands are also diffuse. Both qualitative and quantitative examination of the testes and epididymides of 59 males whose ages have been estimated from tusk dentinal growth layer counts indicate that the male dugong does not produce spermatozoa continuously, despite the absence of a distinct breeding season. Individual dugongs were observed with testes at all stages between complete quiescence and full spermatogenesis, and only 10 of the 40 mature males had fully spermatogenic testes and epididymides packed with spermatozoa. Androgenic and spermatogenic activity of the testes appeared to be in phase, but the testicular histology of some old males suggested that they may have been sterile for long periods.

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