Reproductive products in the adult snow crab (Chionoecetes opilio). I. Observations on spermiogenesis and spermatophore formation in the vas deferens

1999 ◽  
Vol 77 (3) ◽  
pp. 440-450 ◽  
Author(s):  
Guy Sainte-Marie ◽  
Bernard Sainte-Marie

Some of the events unfolding in the vas deferens of the adult snow crab (Chionoecetes opilio) were examined by means of light microscopy. Sperm cells entered the vas deferens as precursors of immature spermatids and developed into immature or mature spermatids within it. However, spermatozoa were not observed in the male reproductive tract. Two types of amorphous matter were added successively to sperm cells in the vas deferens. The first type was periodic acid - Schiff (PAS)-positive and apparently induced spermiogenesis when present in a sufficiently large amount. However, a smaller amount of this amorphous matter was sufficient to form the basal pellicle of spermatophores. The second type was PAS-negative and thickened the wall of spermatophores. Immature and mature spermatids were usually enclosed within distinct spermatophores. Enclosed mature spermatids were connected together by bridges formed by Feulgen-positive spikes coated and extended by PAS-positive amorphous matter. Once broken, the bridges appeared as arms that radiated from a spermatid. Peripheral mature spermatids were furthermore linked to the spermatophore wall by threads of PAS-positive amorphous matter. The bridges and threads may form a pathway for the diffusion of extraneous substances through the spermatophore wall to the innermost cells.

1999 ◽  
Vol 77 (3) ◽  
pp. 451-462 ◽  
Author(s):  
Guy Sainte-Marie ◽  
Bernard Sainte-Marie

Contents of the spermathecae of mated adult snow crabs (Chionoecetes opilio) were examined by light microscopy. The contents could consist of water and three basic types of amorphous matter and of spermatophores. Water was present in the form of large patches or smaller spheres. Of the two major types of amorphous matter, one reacted positively and one negatively to periodic acid - Schiff's reagent (PAS), and one was only, and one predominantly, of male origin. The minor type of amorphous matter was orange and of female origin and could include dark cellular debris. Spermatophores enclosed either immature spermatids, mature spermatids, hitherto unreported spermatozoa, or cell forms intermediate between these three types. Peripheral mature spermatids and spermatozoa had a polarized orientation and were attached to the spermatophore wall. Overall, amorphous matter and spermatophores were topographically segregated by type within a spermatheca, and spermatophores enclosing immature spermatids occurred mostly in PAS-negative amorphous matter. Spermatid differentiation can unfold in the female reproductive tract as well as in the vas deferens, while the transformation of spermatids into spermatozoa was observed only in the female. The diversity of sperm cell types and the ordered placement of semen constituents within the spermatheca suggest that sperm are partitioned for short- or long-term use.


2021 ◽  
Vol 8 ◽  
Author(s):  
Eduardo G. Aisen ◽  
Wilfredo Huanca López ◽  
Manuel G. Pérez Durand ◽  
Edita Torres Mamani ◽  
Juan C. Villanueva Mori ◽  
...  

The viscous seminal plasma (SP) is currently a major impediment to the handling of ejaculate and the development of some biotechnologies in South American camelids. The vas deferens-collected spermatozoa of alpacas is a useful technique to avoid this problem. On the other hand, SP contains a large protein component that has been implicated in the function of spermatozoa within the female reproductive tract. In this sense, the low fertility achieved using transcervical insemination with frozen-thawed spermatozoa in alpacas could be improved by adding SP. This study aimed to evaluate the effect of the whole SP on some in vitro parameters of alpaca spermatozoa after the freezing-thawing-process and the fertility after artificial insemination. It would contribute to a better understanding of the interaction between thawed sperm cells and SP. Spermatozoa were obtained by surgically diverted vas deferens. The samples were diluted with a Tris-based extender, packaged in straws, and frozen. At thawing, each straw was divided into two post-thawing conditions: with the addition of 10% of PBS (control) or with 10% SP (treatment). The sperm cells were evaluated using dynamic parameters, sperm cell morphology, and morphometry. Fertility was assessed by an artificial insemination trial. All in vitro parameters were analyzed by ANOVA. A heterogeneity test was scheduled for the fertility trial. After the freezing-thawing process, motility and plasma membrane functionality was improved when SP was added. No differences were found for post-thaw viability between the control and treatment samples. The percentage of normal cells was higher with SP at post-thawing, and a decrease of the presence of bent tailed spermatozoa with a droplet in the SP group was observed. The length of the head spermatozoa was 3.4% higher in the samples with PBS compared to those in which SP was added. Females pregnant at day 25 post-insemination were 0/12 (with SP inside the straw) and 1/10 (without SP inside the straw). In conclusion, the presence of 10% SP at post-thawing improves sperm cells' motility, functionality, and morphology, indicating that it would be beneficial to improve the frozen-thawed alpaca's physiology spermatozoa. More fertility trials must be developed to increase this knowledge.


Parasitology ◽  
1966 ◽  
Vol 56 (2) ◽  
pp. 347-358 ◽  
Author(s):  
A. O. Anya

The histological anatomy of the male reproductive tract as well as the cytochemistry of the cells of different regions of the male tract in Aspiculuris tetraptera are described.It is shown that there are at least three different regions of the vas deferens, each of which releases one or more substances into the lumen of the male system and thus contributes to the composition of the semen. The histochemical nature of these secretions is given and it is suggested that the secretions of the distal vas deferens are oxytocic.My thanks are due to Professor J. D. Smyth of the Australian National University, Canberra, for the gift of RNA-ase (L. Light and Co.) and some other histochemical reagents, to Dr T. R. R. Mann, C.B.E., F.R.S., and Dr D. L. Lee, for helpful discussions during the course of this study and for reading the draft manuscript.


Author(s):  
M. Crepeau ◽  
S. Yamashiro ◽  
T. Bast ◽  
B.A. Croy

Mus caroli blastocysts transferred to the uterus of pseudopregnant Mus musculus implant but do not survive past midgestation. Blastocyst microsurgery has been used to show that trophoblast is the tissue responsible for pregnancy failure but the nature of the failure remains undefined. Therefore a histological study, was undertaken to compare development of M. caroli embryos in M. musculus and M. caroli uteri at a time point just prior to development of grossly observable lesions.Seven transferred M. caroli embryos and six transferred M. musculus embryos were recovered from three M. musculus recipients on day 8.5 of gestation. Four M. caroli embryos recovered from a M. caroli uterus on day 7.5 of gestation were used as stage-matched controls. For light microscopy, 2 μm thick, glycol methacrylate embedded (3), sections of implantation sites were stained with H & E or periodic acid-Schiff (PAS). For electron microscopy, small pieces of the tissues were fixed and processed routinely.


2019 ◽  
Author(s):  
Jing Gao ◽  
Guanqun Gao ◽  
Lulu Dai ◽  
Jiaxing Wang ◽  
Hui Chen

Abstract Background Trypophloeus Klimeschi Eggers (Coleoptera: Curculionidae: Scolytinae) is one of the most destructive pests of Populus alba var. pyramidalis (Bunge), resulting in significant losses in economic, ecological and social benefits in China’s northwest shelter forest. But research of reproductive system, spermiogenesis and spermatozoon ultrastructure of T. klimeschi that is basis of phylogeny, reproductive biology and controlling is still black. Results The male reproductive organ of T. klimeschi is composed of testis, seminal vesicle, strand shaped accessory gland containing long branch of strand shaped accessory gland and short branch of strand shaped accessory gland, curly accessory gland, vas deferens and a common ejaculatory duct. The number of sperm per cyst is 350~512. Its spermatozoon is slender, measuring about 75 μm in length and 0.5 μm in wide and composed of a 3-layred acrosomal complex, a nucleus with two different states of aggregation, two mitochondrial derivatives with dark crystal, a 9+9+2 axoneme that run more or less parallel to mitochondrial derivatives, two crystalline accessory bodies with a big compact “puff”-like expansion. Especially in the seminal vesicle, its long flagella folded into several turns and the whole sperm is wrapped in a film.Conclusion The general morphology of male reproductive tract, the spermatogenesis and the spermatozoa of T. klimeschi are, for the most part, similar to the majority of the Curculionidae. However, some distinct differences were found: the low electron-dense band in the cytoplasm of spermatocytes; two different aggregation states of spermatozoon nucleus; especially the stored way of T. klimeschi spermatozoa.


1985 ◽  
Vol 248 (3) ◽  
pp. E274-E280 ◽  
Author(s):  
T. T. Turner ◽  
L. L. Ewing ◽  
C. E. Jones ◽  
S. S. Howards ◽  
B. Zegeye

The control of androgen concentrations in the intraluminal fluids of the male reproductive tract is not well understood. The present experiments were performed to determine the effects of hypophysectomy, hypophysectomy plus testosterone (T), and hypophysectomy plus pregnenolone treatment on intraluminal androgen concentrations in the adult rat testis and epididymis. T and 5 alpha-dihydrotestosterone (DHT) concentrations were determined in the vascular, interstitial, and intraluminal compartments of the epididymis. Testicular and epididymal morphology also were examined under light microscopy. Hypophysectomy of at least 5 days duration significantly reduced T and DHT concentrations in serum, tissues, and intraluminal fluids of the reproductive tract. T replacement for 14 days, which produced peripheral T concentrations of 5 ng/ml, did not support intraluminal androgen concentrations in the seminiferous tubules equivalent to controls; rete testis androgen concentrations were similar to controls, however. Pregnenolone administration at 2 mg X rat-1 X day-1 for 14 days did not maintain spermatogenesis nor intraluminal T concentrations in the seminiferous tubules equivalent to controls; however, a low level of spermatogenesis continued when intraluminal and tissue androgen concentrations were maintained at 10-20% of controls by either the testosterone and pregnenolone treatments.


1992 ◽  
Vol 70 (2) ◽  
pp. 314-319 ◽  
Author(s):  
K. Halcrow ◽  
C. G. H. Steel

Morphometrically mature male snow crabs, Chionoecetes opilio, are not known to molt; they are believed to lack functional Y-organs and hence molting hormones. Small regions of the dorsal surface of crabs were damaged and the ensuing repair of the cuticle was followed by light microscopy at intervals of up to 60 days. Events within the limb base after forced autotomy of a single pereiopod were also investigated and compared with cuticle deposition in limb bases of pereiopods autotomized before the crabs' arrival in the laboratory. Circulating ecdysteroids were assayed by radioimmunoassay at intervals throughout the experiments. New cuticle was deposited in response to all types of injury and in a manner similar to that described previously. New cuticle was deposited across the breakage plane of autotomized limb bases; a complete and substantial layer was present in many of the bases of previously autotomized legs. Neither basal growth nor premolt growth was detected in the base of any autotomized limb. Ecdysteroids were detectable in the hemolymph of most crabs but at low titers, ranging from 6.0 to 11.6 ng/mL.


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