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Oxidative stress is one of the main causes of loss of sperm function during chilled storage. The aim of the current study was to evaluate the effects of a fructose-based extender, which was supplemented with catalase or uric acid, on the motility, viability, morphological integrity, and lipid peroxidation (LPO) of Colossoma macropomum spermatozoa. Sperm was diluted in extenders containing catalase (0; 0.1; 0.8; and 1.5 kU/L) or uric acid (0; 0.25; 0.5; and 1.0 mmol/L) and then stored at 4.3 ± 0.6°C for 96 hours. The chilling storage time had more significant and pronounced effects on practically all the measured sperm quality parameters than the different concentrations of both antioxidants added to the extenders. This was true for sperm motility, motility duration, sperm viability, and the percentage of normal spermatozoa. In fact, for all these parameters, values were higher in the extenders supplemented with catalase or uric acid, than those not supplemented with these antioxidants, especially after 96 hours. The LPO process showed an antioxidant-dependent response. In catalase-supplemented extenders thiobarbituric acid reactive substance (TBARS) levels increased gradually and significantly with time, but remained stable during the 96 hours of chilled storage in all samples in which uric acid was added. Despite this, TBARS levels were lower in the extenders supplemented with both catalase and uric acid than in those not having these antioxidants. Inverse correlations were found between sperm motility and the damage in sperm flagella. Our findings suggest that the supplementation of an extender with catalase or uric acid is beneficial and protects fish sperm membranes from damage caused by oxidative stress during low-temperature storage. The extenders containing 0.1 kU/L of catalase and 0.25 mmol/L of uric acid provided effective antioxidant protection for the spermatozoa of this important Amazonian fish.

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The spermatheca and colleterial glands of female insects are organs associated with the reproductive system, responsible for sperm storage and secretion of egg coverings, respectively. Here we compared the development, secretory activity, and chemical nature of the secretion in the spermatheca and colleterial glands of different-aged females of the drywood termite Cryptotermes brevis. We also provide the ultrastructure of these organs in alate females. These structures have been poorly investigated in termites when compared to other eusocial insects (Hymenoptera) and termite-related dictyopterans (mantises and cockroaches). The spermatheca of C. brevis comprises a cone-shaped structure, connected to the genital chamber by a short duct. The colleterial glands, in turn, are divided into anterior and posterior tubules, each showing a basal trunk, and join into a common duct. Histological and histochemical analyses showed that the secretion of proteins and polysaccharides by the spermatheca takes place before pairing, but increases as females mate and store sperm. Colleterial glands of alates showed non-synchronous secretory activity, but the synthesis of products increased in egg-laying queens, together with the epithelium height. Ultrastructure of the spermatheca and colleterial glands revealed epithelia composed of class III secretory cells. Richness of mitochondria and electron-dense secretion in the spermatheca indicates synthesis and transport of content. Presence and absence of colleterial gland secretion in different individuals may reflect variable maturation stages of the females and secretory cells. Assuming that termites are iteroparous, the development and secretion of the spermatheca and colleterial glands play a crucial role for C. brevis queens.

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The Corynorhinus mexicanus bat is characterized by a specific form of reproductive asynchrony between males and females. After mating, some sperm remain in the male's epididymis, the organ where the sperm had matured. It has not yet been determined if apoptotic markers participate in the process of the maturation and/or elimination of these cells, so studying this topic is essential for our understanding of this species. Male bats were collected during three stages: Before mating; during the Mating phase; After mating and the final phase, which we call, Storage. Their epididymides were removed, weighed and measured. Sperm were extracted and the following sperm parameters were evaluated: active caspases, phosphatidylserine externalization, and mitochondrial membrane potential. Sperm from the testes enter the epididymis during Before mating, causing the organ to grow. During Mating phase, spermatozoa present a large amount of active caspases with externalization of phosphatidyl serine, even while still alive. This suggests that these two markers could participate in maturation and elimination, respectively.

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Mammalian sperm capacitation involves biochemical and physiological changes, such as an increase in intracellular calcium ion concentration ([Ca2+]i), hyperpolarization of the plasma membrane potential and sperm hyperactivation, among others. These changes provide sperm with the ability to fertilize. In the bat Corynorhinus mexicanus, there is an asynchrony between spermatogenesis and sperm storage in the male with the receptivity of the female. For instance, in C. mexicanus, spermatogenesis occurs before the reproductive season. During the reproductive period, sperm are stored in the epididymis for a few months and the testis undergoes a regression, indicating low or almost null sperm production. Therefore, it is unclear whether the elements necessary for sperm fertilization success undergo maturation or preparation during epididymis storage. Here, we characterized pH-sensitive motility hyperactivation and Ca2+ influx in sperm, regulated by alkalinization and progesterone. In addition, by electrophysiological recordings, we registered currents that were stimulated by alkalinization and inhibited by RU1968 (a CatSper-specific inhibitor), strongly suggesting that these currents were evoked via CatSper, a sperm Ca2+-specific channel indispensable for mammalian fertilization. We also found hyperpolarization of the membrane potential, such as in other mammalian species, which increased according to the month of capture, reaching the biggest hyperpolarization during the mating season. In conclusion, our results suggest that C. mexicanus sperm have functional CatSper and undergo a capacitation-like process such as in other mammals, particularly Ca2+ influx and membrane potential hyperpolarization.

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This study describes the mating behavior of Hypoconcha parasitica under laboratory conditions highlighting the spermathecal morphology and focusing on the seminal fluid storage and release of spermatozoa. The pairs were kept in aquaria where the mating behavior was recorded and described. The spermathecae of the female were analyzed using scanning electron microscopy, X-ray micro-CT, histology, and histochemistry. No pre- or post-copulatory mate guarding was observed in H. parasitica. The sperm transfer occurred with each pair maintaining the protection shield (bivalve shell) on their dorsum. The pair of spermathecae is covered exclusively by the cuticle, following the Podotremata pattern. Many muscle fiber bundles are attached to the cuticular wall facing toward the cephalothorax cavity, especially covering the lateral and slightly dorso-anterior region toward the apodeme of Sternite 7. The spermathecal organization indicates that the process of sperm release during fertilization occurs through muscular action exerted by the female on the wall of the chamber. Thus, the musculature distribution in Hypoconchinae distinguishes them from described for other Podotremata such as Homolidae, which shows the musculature associated with the spermathecae aperture. Like the Homolidae, the first pleopod in H. parasitica seems to take part in the transfer/ movement of spermatozoa and oocytes between the sternum and abdomen, which forms a temporary chamber where fertilization occurs. In conclusion, the spermathecal morphology and associated structures bring new insights to the mechanisms involved in the sperm storage and fertilization of primitive crabs and how the Dromiidae spermatheca perform a new pattern among the poorly studied Podotremata.

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Studies on reproductive biology have largely contributed to the understanding of snake ecology. However, detailed reproductive data are scarce for many groups, particularly blind snakes. Here, we describe the reproductive biology of Trilepida koppesi (Leptotyphlopidae), a widely distributed species in the savannas of south-central Brazil. We describe its macro- and microscopic reproductive anatomy, female reproductive cycle, potential clutch size, seasonal activity, and sexual dimorphism of a population from south-eastern Brazil. Males have plurilobulated testes. Spermiogenesis occurs in early spring (October), when gonads and kidneys show a textured surface, the sexual segment of the kidney is hypertrophied, and the ductus deferentia are opaque and packed with sperm. Females have only the right oviduct, which shows developed epithelium and uterine glands in spring. Mating likely occurs in spring (October–December), and females store sperm in infundibular receptacles until ovulation between late spring and early summer. Potential clutch size ranges from three to five eggs. Females grow larger than males. The synchrony between spermiogenesis and mating defines the male cycle as prenuptial, which is considered the ancestral state of Squamata. These results agree with the hypothesis of conservative parameters for the group.

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Reproduction in snakes employs a wide range of mechanisms such as long-term sperm storage, mating aggregations and male–male combat. These varied mechanisms can be better understood when combined with the study of the ultrastructural morphological variability of spermatozoa. Within the coral snakes, genus Micrurus, there are differences in the reproductive strategies adopted between monads (BRM) and triads (BRT); the aim of this work was to relate these two strategies to morphological differences among spermatozoa within different species. The semen of six Micrurus was collected using a non-invasive technique, fixed and processed for scanning and transmission electron microscopy. Micrurus spermatozoa have the same ultrastructure as those of other snake species, comprising the head, divided into acrosome, nucleus and neck; the midpiece; and the two parts of the tail, the principal piece and the end piece. Micrurus corallinus and Micrurus surinamensis presented evident multilaminar membranes occurring along all the pieces, while Micrurus frontalis and Micrurus altirostris showed cytoplasmic droplets occurring mainly in the midpiece. The differences found in spermatozoa morphology may be related with sperm storage in these four coral snakes, since the development of multilaminar membranes in the midpiece and the maintenance of cytoplasmic droplets in the mature sperm are both features related to extra energy provision for the spermatozoa while stored.

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Sea slugs are interesting models to study post-copulatory sexual selection in simultaneous hermaphrodites due to the enormous variation of their reproductive systems. However, the knowledge of the functional morphology of their reproductive system is limited to few species, and it is rarely discussed in the context of sexual selection theory. In this study, we investigated the functional morphology of the sperm-containing chambers (i.e., ampulla, seminal receptacle, and bursa copulatrix) of the reproductive system of Okenia polycerelloides (Ortea & Bouchet, 1983), based on light, confocal, and electron microscopy. Although the morphology of the ampulla is similar to other species, indicating that it is a site for autosperm storage, we found some sperm facing the ampullar epithelium, a feature commonly regarded as characteristic of the seminal receptacle of sea slugs. The seminal receptacle of O. polycerelloides showed secretory activity and contained sperm with distribution and orientation suggestive of stratification of allosperm from distinct mating events, a feature that would affect sperm competition. The bursa copulatrix had epithelial cells with secretory and absorptive characteristics, and contained degraded sperm and yolk granules within its lumen. Comparative analyses of the contents of each organ demonstrated that sperm digestion occurs in the bursa copulatrix and affects sperm heads first, changing their morphology from slender and curved to shorter and ellipsoid before complete lysis. Although digestion and absorption of surplus sperm are currently the main hypothesized functions for the bursa copulatrix, its role in cryptic female choice should not be ruled out. The close structural connection between the seminal receptacle and bursa copulatrix, as well as their muscular walls, would enable control over the fate of the sperm received in each mating event, that is, storage or digestion.

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Myotis levis (yellowish myotis) is a small Neotropical insectivorous vespertilionid bat that provides valuable ecosystem services, such as control of disease vectors and agricultural pests. Aiming to describe the fluctuations of the reproductive organs throughout the year, the gonads and epididymis from 124 adult bats were histologically evaluated. These animals were captured in Santuário do Caraça, Minas Gerais, Brazil. After the initial screening, six bats per reproductive stage (in a representative month) had specific organs harvested for further investigation. The gonads, epididymis, accessory sex gland and brown adipose tissue were collected for biometric analyses. Furthermore, yellowish myotis testis was evaluated through histomorphometric and molecular assays, whereas blood samples were collected for hormonal analyses. The data were compared among the reproductive stages and correlated with rainfall distribution. As a result, we demonstrated that yellowish myotis presented a seasonal reproduction showing testis regression and rest, resembling the pattern exhibited by temperate-zone vespertilionid bats. During the Mature stage, after the peak of rainfall distribution, yellowish myotis testicles were fully developed for gamete production and maximum testosterone synthesis. These findings indicate a significant influence of this environmental factor on yellowish myotis reproduction. Following that, the accessory sex gland, brown adipose tissue and epididymis weights increased in the Regressed stage. The epididymis sperm storage occurred for at least 8 months and was observed in the Regressed, Rest and beginning of the Maturing stage. This reproductive fluctuation is interesting because the reactivation of the gonads coincided with the least amount of sperm in the epididymis.

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Seminal gifts range from important material donations to items that provide little direct benefit to females. Promiscuous, female silk corn flies Euxesta eluta expel and consume male ejaculates immediately after mating. The evolution and function of this peculiar behavior are currently unknown. We performed a series of experiments aimed to: determine if females under different dietary regimes derive nutrients or water for survival and/or reproduction from ejaculate consumption, if males suffer a fitness cost from supplying females with ejaculates, and if females prefer to mate and/or are more likely to store sperm from well fed than nutritionally stressed presumably inferior males. Experiments revealed that protein deprived E. eluta females derive nutrients for ovarian development through consumption of ejaculates of protein fed males. No seminal products affecting survival appear to be transferred in the consumed ejaculate. However, ovarian development, in contrast to testes growth, occurs in detriment of longevity. Females preferred to mate with protein fed males, yet sperm retention in spermathecae was extremely rare after a single mating. This finding suggests that females could be exerting post copulatory control. A key question that remained to be addressed for the understanding of this puzzling and promiscuous mating system is what ecological factors or male traits drive females to retain sperm from one or several males in order to achieve and/or maximize fertilization potential.

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Reproductive traits vary widely within and among snake species, and are influenced by a range of factors. However, additional studies are needed on several species, especially on tropical snake faunas, to fully understand the patterns of reproductive variation in snakes. Here, we characterized the reproductive biology of B. jararacussu from southeastern and southern Brazil. We combined macroscopic and microscopic examinations of the reproductive system of museum specimens with observations of free-ranging snakes to characterize size at sexual maturity, sexual size dimorphism (SSD), reproductive output, and male and female reproductive cycles. We compared our data with published literature and discuss the factors that may play a role in shaping the reproductive patterns in the species and the genus. Bothrops jararacussu shares several characteristics with its congeners such as autumn mating season, obligatory sperm storage in the female reproductive tract, seasonal timing of parturition (summer-autumn), female-biased SSD, maturity at larger body sizes in females, and a positive relationship between body size and litter size. These characteristics seem phylogenetically conserved in Bothrops. On the other hand, B. jararacussu exhibits some unique characteristics such as a high degree of SSD (one of the highest values recorded in snakes), a large female body size, and a large litter and offspring size, which are among the largest recorded in the genus. Moreover, larger females reproduce more frequently than smaller conspecifics. These characteristics may be collectively interpreted as the result of a strong selection for increased fecundity. Other peculiarities of the species include an asynchrony between spermiogenesis (summer-autumn) and the peak of SSK hypertrophy (autumn to spring) and a prolonged production of SSK granules. Because SSK hypertrophy and mating are androgen-dependent in snakes, the prolonged SSK hypertrophy suggests that male B. jararacussu may prolong their potential to mate (compared with its congeners), which may increase their reproductive success. Our results and previous literature collectively suggest that, in Bothrops, the evolution of SSD is driven by fecundity selection, variation in reproductive output is influenced by variation in female body size, and the timing of spermiogenesis is influenced by other factors in addition to temperature. We also suggest that male Bothrops have undergone multiple evolutionary shifts in the timing of spermiogenesis.

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Knowledge of reproductive biology is essential to understand the intrinsic traits of any species and to elaborate effective conservation strategies, particularly for threatened species. Despite recent advances, knowledge on the reproductive biology of snakes remains deficient for most species, especially for tropical fossorial taxa. Apostolepis gaboi is a psammophilous, fossorial, and threatened snake endemic of the Quaternary Sand Dunes of the São Francisco River, Caatinga domain. Here, we present information on its reproductive biology based on macroscopic and microscopic data obtained from the examination of all specimens preserved in Brazilian museums. Specifically, we addressed sexual maturity, sexual dimorphism, clutch size, timing of gametogenesis, activity of the sexual segment of the kidney (SSK), and female sperm storage. Apostolepis gaboi is one of the smallest species of the genus. Females attain sexual maturity at larger body sizes and grow larger than males. However, adult females have relatively shorter tails than males. We found no sexual dimorphism in body circumference and head size. Clutch size is small and averages 4.5 eggs. All males from the wet season showed testes in spermiogenesis, ductus deferentia packed of sperm, and SSK hypertrophied and secretory. Secondary vitellogenesis also occurs in the wet season. Moreover, females in early vitellogenesis from the wet season showed sperm stored in the posterior infundibulum. Mating occurs in the second half of the wet season, as suggested by the finding of aggregations of sperm in the uterine lumen of a female in early secondary vitellogenesis. Mating is associated with gonadal activity in males. Sperm storage confers flexibility for females to ovulate at the most suitable time in an unpredictable habitat such as the Caatinga. Apostolepis gaboi exhibits similarities (association between mating and spermiogenesis, small clutch) and differences (absence of sexual dimorphism in head size and stoutness) compared with another Elapomorphini species. Lastly, we argue that some of the intrinsic traits of A. gaboi (small clutch and small body size) may increase its vulnerability to extinction, raising additional concerns to its conservation.

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We studied the structural and cellular organisation of the oviduct of Erythrolamprus miliaris including its morphological variation during the reproductive cycle using light microscopy, scanning electron microscopy and transmission electron microscopy. Four anatomically distinct regions compose the oviduct of E. miliaris including the anterior and posterior infundibulum, glandular uterus, non-glandular uterus and pouch. The cells of the oviductal epithelium secrete material by apocrine and merocrine processes, which vary between the anatomical regions and according to each phase of the reproductive cycle. The infundibular epithelium secretes electron dense vacuoles, which suggests the production of lipids, whereas the epithelial secretion of the glandular uterus, non-glandular uterus and pouch creates lucent and slightly electron dense vacuoles, indicating the production of glycoproteins. The timing of mating, vitellogenesis and sperm storage directly influences the morphofunctional alterations in the oviducts of E. miliaris. Sperm storage occurs only in the infundibular receptacles with increased production of the neutral carbohydrates in the presence of male gametes. Sperm storage happens in vitellogenic, non-vitellogenic and pregnant females of E. miliaris. Thus, females may be able to produce multiple clutches at different seasons of the year regardless of mating during autumn.

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The cauda epididymidis is the major sperm storage region whose androgenic supply, essential for the sperm viability, is provided by the vasculature and is dependent upon testosterone diffusion through the stromal tissue to reach the epithelial cells. We have focused our efforts on examining the regulation of this important epididymal region by evaluating the impact of the androgen disrupter cimetidine on the epithelial-stromal androgenic microenvironment. Male rats received 100 mg/kg cimetidine (CMTG) or saline (CG) for 50 days, serum testosterone levels were measured and the epididymal cauda region was processed for light and transmission electron microscopy. In the proximal cauda region, the duct diameter was measured and birefringent collagen in the stroma was quantified. TUNEL-labeled epithelial cells were quantified, and androgen receptor (AR), karyopherin alpha (KPNA) and sex hormone-binding globulin (SHBG) levels were analyzed by immunofluorescence and Western blot. CMTG showed reduced duct diameter and high number of apoptotic epithelial cells. In the epithelium, the total AR concentration and the KPNA immunoreactivity were reduced, and a weak/absent AR nuclear immunofluorescence was observed in contrast to the enhanced AR immunolabeling observed in the cytoplasm of the epithelial cells. A significant reduction of collagen and SHBG levels in the stroma was also observed. Cimetidine treatment impairs AR nuclear import in the epithelium, causing androgenic dysfunction and subsequent epithelial cell apoptosis and duct atrophy. The connective tissue atrophy and reduction of SHBG stromal levels associated with epithelial androgenic dysfunction indicate a possible role of stromal SHBG in the androgenic supply of the sperm storage region of the epididymis.

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Cubozoans (box jellyfish) are gonochoristic cnidarians with distinct reproductive strategies. This comparative histological study examines the gonad organization of Alatina alata and Copula sivickisi, two box jellyfish species that exhibit different modes of internal fertilization. A. alata reproduces via spermcasting aggregations while C. sivickisi reproduces via copulation; in both cases, internal fertilization occurs in the gastrovascular cavity. Herein, we provide the first histological description of subgastric sacs-structures unique to C. sivickisi. Although previously thought to function as sperm storage sacs, our findings reveal that subgastric sacs are nematocyst nests lacking sperm entirely. Conversely, we discovered that velarial spots in C. sivickisi females correspond to actual sperm storage structures. Histological examination of cubozoan sperm packages revealed that while sperm packages from both species have motile flagella, A. alata males produce nonencapsulated sperm bundles (i.e., "spermatozeugmata"), and C. sivickisi males produce encapsulated packages (i.e., "spermatophores"). Our findings corroborate the presence of several types of nematocysts in C. sivickisi embryo strands and spermatophores, and indicate their provenance to be both female and male gonads respectively, as well as subgastric sacs (i.e., nematocyst nests). In contrast to our findings of velarial spots as sperm storages structures in C. sivickisi females, and of nematocysts in the gonads of both sexes, we report that A. alata medusae lack both sperm storage structures and gonadal nematocysts. Finally, we discuss our findings on reproductive morphology of C. sivickisi and A. alata in light of the respective reproductive behavior of these two cubozoan species.

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In this study, we describe the female reproductive cycle of Philodryas patagoniensis in south Brazil, which was described through morpho-anatomical and histological analyses. The peak of secondary vitellogenesis occurred during winter-spring (July-December), ovulation in spring (October-December), mating and fertilization in spring-summer (October-February), oviposition in spring-autumn (October-May) and births from late spring to autumn (December-July). The diameter of vitellogenic follicles/eggs was larger in winter-spring than in other seasons. The diameter of the shell glands was also larger in winter-spring. In spite of the clear reproductive peak, gonads only showed reduced activity in the autumn. Therefore, at the individual level, females have a discontinuous cyclical reproduction; in the populational level, the reproductive cycle is seasonal semisynchronous. We support the hypothesis that P.patagoniensis have the ability to produce multiple clutches with long-term stored sperm. Sexual dimorphism in body size was evident, and females are significantly larger and heavier than males. Larger females were able to produce follicles and eggs in larger amount and size. The maternal body size was positively related to the reproductive effort and fecundity. To conclude, we deliberated about the proximal and distal causes that influence the reproductive traits and patterns of P.patagoniensis.

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Sperm competition is a powerful postcopulatory selective force influencing male adaptations associated with increasing fertilization success, and it is usually related to the evolution of different strategies of ejaculate expenditure between individuals. Ejaculates may also be influenced by additional selective pressures associated with sperm competition, such as timing between insemination and fertilization, female reproductive tract morphology, and fertilization environment. Also, males that adopt alternative mating tactics may face distinct sperm competition pressures, which may lead to the evolution of intraspecific diversity in ejaculates. In loliginid squids, males with alternative reproductive tactics (sneakers and consorts) differ not only in mating behavior, but also transfer spermatophores into two distinct sites within the female. Here, we compared structure and functioning of spermatophores between sneakers and consorts in the squid Doryteuthis plei applying microscopy techniques and in vitro experiments. Sneakers and consorts exhibit differences in spermatophore structure that lead to distinct spermatophoric reactions and spermatangium morphologies. Moreover, in sneakers, sperm release lasts longer and their sperm show an aggregative behavior not detected in consorts. Slow sperm release may be a strategy to guarantee longer sperm provision, given the wide interval between sneaker mating and egg release. For consorts, in turn, intense and quick sperm discharge may be advantageous, as timing between mating and egg-laying is relatively short. Within the complex squid mating system, factors such as (i) different fertilization sites and (ii) interval between mating and egg release may also influence sperm competition, and ultimately shape the evolution of divergent ejaculates between dimorphic males.

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The paired oviducal glands of immature and mature females of Mustelus schmitti were examined macro and microscopically. Findings indicate that these glands possessed the same zonation as in most chondrichthyans from anterior to posterior: club, papillary, baffle and terminal zones. The whole gland is composed by simple tubular glands that connect with transverse grooves all along the organ. The club zone presents a typical indian club shape with a simple columnar and ciliated epithelium including secretory cells PAS (+) and AB (+). The papillary zone is characterized by lamella forming small and long cones in numbers of three. The epithelium of this zone contains ciliated cells with apical nuclei and secretory cells with basal nuclei that stain AB (+)The baffle zone consists of apically flattened lamellae alternating with spinnerets which are small projections disposed by both sides of the plateau. This whole structure is present in number of 8 or 9 units. A simple columnar ciliated epithelium covers the plateau and spinnerets and no AB or PAS staining is observed. The epithelium of the terminal zone is PAS (-) and AB (+), and elongated tubules, that run adjacent to the baffle zone are the site where groups of spermatozoa are clearly observed in the lumen. The epithelium of the sperm storage tubules do not stain with any of the dyes tested. Sperm was also observed in the baffle zone, presumably in its way to the fecundation in the oviduct because it displays no aggregation pattern and was between the folds of the epithelium. By scanning electron microscopy sperm was observed in the club and baffle zones in a gland which belonged to a pregnant female.(AU)

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The paired oviducal glands of immature and mature females of Mustelus schmitti were examined macro and microscopically. Findings indicate that these glands possessed the same zonation as in most chondrichthyans from anterior to posterior: club, papillary, baffle and terminal zones. The whole gland is composed by simple tubular glands that connect with transverse grooves all along the organ. The club zone presents a typical indian club shape with a simple columnar and ciliated epithelium including secretory cells PAS (+) and AB (+). The papillary zone is characterized by lamella forming small and long cones in numbers of three. The epithelium of this zone contains ciliated cells with apical nuclei and secretory cells with basal nuclei that stain AB (+)The baffle zone consists of apically flattened lamellae alternating with spinnerets which are small projections disposed by both sides of the plateau. This whole structure is present in number of 8 or 9 units. A simple columnar ciliated epithelium covers the plateau and spinnerets and no AB or PAS staining is observed. The epithelium of the terminal zone is PAS (-) and AB (+), and elongated tubules, that run adjacent to the baffle zone are the site where groups of spermatozoa are clearly observed in the lumen. The epithelium of the sperm storage tubules do not stain with any of the dyes tested. Sperm was also observed in the baffle zone, presumably in its way to the fecundation in the oviduct because it displays no aggregation pattern and was between the folds of the epithelium. By scanning electron microscopy sperm was observed in the club and baffle zones in a gland which belonged to a pregnant female...

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This study describes the seminal and spermatic characteristics of fresh semen of Steindachneridion melanodermatum and investigates the effects of dilution, temperature, and storage period on its spermatic parameters. Sperm samples were collected from nine hormonally-induced males. The following parameters in fresh sperm were analyzed: seminal plasma osmolality (OSM), seminal pH, sperm motility (MOT), sperm velocity (SV) (including sperm curvilinear velocity (CVV), sperm straight-line velocity (SLV), and sperm average path velocity (APV)), total time of sperm motility (TEMP), sperm concentration (CONC), and index of sperm normality (NORM). Sperm samples from each male were diluted in a solution containing 5% fructose and 5% powdered milk, and stored at 10C and 25C. The same was carried out for sperm samples not subjected to dilution. From these samples, MOT, CVV, SLV, APV, SV, and TEMP were measured after 0 h, 5 h, 9 h, 18 h, 27 h, 36 h, 45 h, and 54 h. Males released 11.74 ± 5.38 mL of sperm, with an osmolality of 258.78 ± 29.36 mOsm.kg-1 and pH of 7.11 ± 0.31. The sperm presented a MOT of 99.86 ± 0.31% at a concentration of 1.03 × 1010 ± 3.65 × 109 spermatozoa.mL-1 with CVV of 185.58 ± 14.11 ?m.s-1, SLV of 49.15 ± 4.66 ?m.s-1, APV of 87.02 ± 4.13 ?m.s-1, SV of 106.52 ± 4.45 ?m.s-1, TEMP of 79.31 ± 5.62 s, NORM of 75.81 ± 5.71%. The resultsindicate that sperm motility, sperm velocity, and total time of sperm activation were affected by dilution,storage temperature, and storage period (p < 0.05). Procedures for semen storage should be performed with undiluted sperm cooled at 10°C, or kept undiluted at 25°C for up to 27h.

O objetivo deste estudo foi descrever os parâmetros seminais e espermáticos no sêmen fresco do Steindachneridion melanodermatum e os efeitos da diluição, da temperatura e do tempo de estocagem do sêmen sobre os parâmetros espermáticos. Foi coletado o sêmen de nove machos, induzidos hormonalmente. No sêmen fresco foram avaliados os parâmetros: osmolaridade do plasma seminal (OSM), pH seminal (pH), motilidade (MOT) e velocidades espermáticas (VCL, VLR, VMD, VE), tempo total de motilidade espermática (TEMP), concentração espermática e índice de normalidade espermática (NORM). De cada macho, amostras de sêmen que foram diluídas em solução contendo 5% de frutose e 5% de leite em pó e, armazenadas a 10 e 25ºC. O mesmo foi feito para amostras de sêmen não submetidas à diluição. Destas amostras, as MOT, VCL, VLR, VMD, VE, TEMP foram mensuradas após 0, 5, 9, 18, 27, 36, 45, 54 horas. Os machos liberaram 11,74 ± 5,38 mL de sêmen com 258,78 ± 29,36mOsm.kg-1 e pH de 7,11 ± 0,31. O sêmen apresentou 99,86 ± 0,31% de MOT, com 1,03x1010 ± 3,65x109 espermatozódes.mL-1 e, 185,58 ± 14,11?m.s-1 para VCL, 49,15 ± 4,66?m.s-1 para VLR, 87,02 ± 4,13 ?m.s-1 para VMD, 106,52 ± 4,45?m.s-1 para VE, 79,31 ± 5,62s para TEMP e 75,81 ± 5,71% de NORM. A motilidade, as velocidades e o tempo total de motilidade espermática foram influenciados (p 0,05) pela diluição, pelas temperaturas e tempos de armazenamento. A estocagem do sêmen poderá ser realizado sem diluição e resfriado a 10oC ou sem diluição, a temperatura de 25oC, pelo período deaté 27 horas.

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