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1.
Sci Total Environ ; 934: 172893, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38692321

RESUMO

Being a crucial element for technological development, praseodymium (Pr) has been increasingly used, leading to a rise in its concentration in aquatic systems. However, its potential threats to organisms remain poorly understood. Besides contamination, organisms are also threatened by climate change-related factors, including warming. It is important to evaluate how climate change-related factors may influence the effects of contaminants. To address this, histopathological and biochemical analyses were performed in adult mussels of Mytilus galloprovincialis, following a 28-day exposure to Pr (10 µg/L) and warming (4 °C increase) separately, and in combination. Additionally, biochemical and physiological alterations were analysed in the sperm of mussels after 30-min exposure to the same treatments. Furthermore, it was used the Independent Action model to predict the interaction between Pr and warming. The results showed, in the case of adults exposed to Pr, an increase in superoxide dismutase (SOD) and glutathione S-transferases (GSTs) activities. However, it was insufficient, leading to histopathological injuries, redox imbalance, and cellular damage. In the case of sperm, Pr induced an increase of mitochondrial activity and respiration rate, in response to the increase in systemic metabolic rate and oxygen demand. Warming increased the metabolism, and induced redox imbalance and cellular damage in adults. In sperm, a rise in temperature induced lipid peroxidation and a decrease in velocity. Warming induced some alterations in how adult mussels responded to Pr, activating catalase instead of SOD, and in addition to GSTs, also activated carboxylesterases. However, it was not enough to avoid redox imbalance and cellular damage. In the case of sperm, the combination induced a decrease in H2O2 production, and higher oxygen demand, which prevented the decrease in motility and velocity. This study highlights the limitations of using models and emphasizes the importance of studying the impacts of emerging contaminants, such as rare earth elements, and their combination with climate change-related factors. Under environmental conditions, chronic exposure to the combined effect of different stressors might generate impacts at higher biological levels. This may affect organisms' respiratory and filtration capacity, nutrient absorption, defence capacity against infections or diseases, and sperm viability, ultimately resulting in reduced growth and reproduction, with consequences at the population level.


Assuntos
Mudança Climática , Mytilus , Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/toxicidade , Mytilus/fisiologia , Masculino , Espermatozoides/fisiologia , Temperatura Alta/efeitos adversos , Superóxido Dismutase/metabolismo , Glutationa Transferase/metabolismo
2.
Reprod Fertil Dev ; 362024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38769680

RESUMO

Context Conventional sperm quality tests may not be sufficient to predict the fertilising ability of a given ejaculate; thus, rapid, reliable and sensitive tests are necessary to measure sperm function. Aims This study sought to address whether a cluster analysis approach based on flow cytometry variables could provide more information about sperm function. Methods Spermatozoa were exposed to either isotonic (300mOsm/kg) or hypotonic (180mOsm/kg) media for 5 and 20min, and were then stained with SYBR14 and propidium iodide (PI). Based on flow cytometry dot plots, spermatozoa were classified as either viable (SYBR14+ /PI- ) or with different degrees of plasma membrane alteration (SYBR14+ /PI+ and SYBR14- /PI+ ). Moreover, individual values of electronic volume (EV), side scattering (SS), green (FL1) and red (FL3) fluorescence were recorded and used to classify sperm cells through cluster analysis. Two strategies of this approach were run. The first one was based on EV and the FL3/FL1 quotient, and the second was based on EV, SS and the FL3/FL1 quotient. Key results The two strategies led to the identification of more than three sperm populations. In the first strategy, EV did not differ between membrane-intact and membrane-damaged sperm, but it was significantly (P P P Conclusions Cluster analysis based on flow cytometry variables provides more information about sperm function than conventional assessment does. Implications Combining flow cytometry with cluster analysis is a more robust approach for sperm evaluation.


Assuntos
Citometria de Fluxo , Pressão Osmótica , Análise do Sêmen , Espermatozoides , Citometria de Fluxo/métodos , Masculino , Espermatozoides/fisiologia , Análise do Sêmen/métodos , Análise do Sêmen/veterinária , Análise por Conglomerados , Membrana Celular/fisiologia , Motilidade dos Espermatozoides/fisiologia , Animais
3.
Reprod Fertil ; 5(1)2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-38367345

RESUMO

Abstract: Poly- and per-fluoroalkyl substances (PFAS) are synthetic environmentally persistent chemicals. Despite the phaseout of specific PFAS, their inherent stability has resulted in ubiquitous and enduring environmental contamination. PFAS bioaccumulation has been reported globally with omnipresence in most populations wherein they have been associated with a range of negative health effects, including strong associations with increased instances of testicular cancer and reductions in overall semen quality. To elucidate the biological basis of such effects, we employed an acute in vitro exposure model in which the spermatozoa of adult male mice were exposed to a cocktail of PFAS chemicals at environmentally relevant concentrations. We hypothesized that direct PFAS treatment of spermatozoa would induce reactive oxygen species generation and compromise the functional profile and DNA integrity of exposed cells. Despite this, post-exposure functional testing revealed that short-term PFAS exposure (3 h) did not elicit a cytotoxic effect, nor did it overtly influence the functional profile, capacitation rate, or the in vitro fertilization ability of spermatozoa. PFAS treatment of spermatozoa did, however, result in a significant delay in the developmental progression of the day 4 pre-implantation embryos produced in vitro. This developmental delay could not be attributed to a loss of sperm DNA integrity, DNA damage, or elevated levels of intracellular reactive oxygen species. When considered together, the results presented here raise the intriguing prospect that spermatozoa exposed to a short-term PFAS exposure period potentially harbor an alternate stress signal that is delivered to the embryo upon fertilization. Lay summary: PFAS are synthetic chemicals widely used in non-stick cookware, food packaging, and firefighting foam. Such extensive use has led to concerning levels of environmental contamination and reports of associations with a spectrum of negative health outcomes, including testicular cancer and reduced semen quality. To investigate the effects of PFAS on male reproduction, we incubated mouse sperm in a cocktail of nine PFAS at environmentally relevant concentrations before checking for a range of functional outcomes. This treatment strategy was not toxic to the sperm; it did not kill them or reduce their motility, nor did it affect their fertilization capacity. However, we did observe developmental delays among pre-implantation embryos created using PFAS-treated sperm. Such findings raise the intriguing prospect that PFAS-exposed sperm harbor a form of stress signal that they deliver to the embryo upon fertilization.


Assuntos
Fluorocarbonos , Neoplasias Embrionárias de Células Germinativas , Doenças dos Roedores , Neoplasias Testiculares , Masculino , Camundongos , Animais , Neoplasias Testiculares/veterinária , Análise do Sêmen/veterinária , Espécies Reativas de Oxigênio/farmacologia , Sêmen , Espermatozoides/fisiologia , DNA/farmacologia , Fluorocarbonos/toxicidade
4.
Evolution ; 77(1): 199-209, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36622801

RESUMO

Measuring reproductive costs is crucial to understanding sexual conflict and its evolutionary outcomes. Sexual conflict is thought to originate from anisogamy-the size difference between male and female gametes; if sperm are tiny and not produced in vastly greater numbers than eggs, at any mating females' gametic investment is larger than that of males. Testing this prediction has proven difficult, especially because males and females differ in many more traits than just gamete size. We overcame this difficulty by exposing simultaneously hermaphroditic polychaete worms Ophryotrocha diadema (two sexual functions in the same body) to two social conditions, pairs, and groups >2, where hermaphrodites invest either relatively more in the female function or relatively more in the male function, respectively. Then we measured four markers of cellular oxidative status, a physiological mediator of life-history strategies. Less female-biased hermaphrodites produced fewer eggs but, unexpectedly, had lower levels of antioxidant protection than more female-biased hermaphrodites, which produced more eggs. Male-biased hermaphrodites compete for mating as males (hermaphrodites in pairs do not) suggesting that in the short-term male competition might be costlier than egg production in terms of regulation of oxidative status. These results highlight the need of including behavioral traits, namely competition over egg fertilization, in the measures of reproductive costs.


Assuntos
Reprodução , Sêmen , Animais , Masculino , Feminino , Espermatozoides/fisiologia , Fertilização , Estresse Oxidativo
5.
Insect Sci ; 30(1): 232-240, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35656827

RESUMO

Male animals often adjust their sperm investment in response to sperm competition environment. To date, only a few studies have investigated how juvenile sociosexual settings affect sperm production before adulthood and sperm allocation during the first mating. Yet, it is unclear whether juvenile sociosexual experience (1) determines lifetime sperm production and allocation in any animal species; (2) alters the eupyrene : apyrene sperm ratio in lifetime ejaculates of any lepidopteran insects, and (3) influences lifetime ejaculation patterns, number of matings and adult longevity. Here we used a polygamous moth, Ephestia kuehniella, to address these questions. Upon male adult emergence from juveniles reared at different density and sex ratio, we paired each male with a virgin female daily until his death. We dissected each mated female to count the sperm transferred and recorded male longevity and lifetime number of matings. We demonstrate for the first time that males ejaculated significantly more eupyrenes and apyrenes in their lifetime after their young were exposed to juvenile rivals. Adult moths continued to produce eupyrene sperm, contradicting the previous predictions for lepidopterans. The eupyrene : apyrene ratio in the lifetime ejaculates remained unchanged in all treatments, suggesting that the sperm ratio is critical for reproductive success. Male juvenile exposure to other juveniles regardless of sex ratio caused significantly shorter adult longevity and faster decline in sperm ejaculation over successive matings. However, males from all treatments achieved similar number of matings in their lifetime. This study provides insight into adaptive resource allocation by males in response to juvenile sociosexual environment.


Assuntos
Mariposas , Masculino , Feminino , Animais , Mariposas/fisiologia , Gastos em Saúde , Comportamento Sexual Animal/fisiologia , Sêmen , Espermatozoides/fisiologia
6.
Anim Reprod Sci ; 246: 106849, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34556397

RESUMO

Evaluation of sperm motility is well-established in farm animals for quickly selecting ejaculates for semen processing into insemination doses and for evaluating the quality of preserved semen. Likewise, sperm motility is a fundamental parameter used by spermatologists in basic and applied science. Motility is commonly assessed using computer-assisted semen analysis (CASA). Recent increases in computational power, as well as utilization of mobile CASA systems and open-source CASA programs, broaden the possibilities for motility evaluation. Despite this technological progress, the potential of computer-generated motility data to assess male fertility remains challenging and may be limited. Relevance for fertility assessment could be improved if measurement conditions would more closely mimic the in vivo situation. Hence, this review is focused on the current trends of automated semen assessment in livestock and explores perspectives for future use with respect to the physiological and physical conditions encountered by sperm in the female reproductive tract. Validation of current CASA systems with more complex, microfluidic-based devices mimicking the female reproductive tract environment could improve the value of sperm kinematic data for assessing the fertilizing capacity of semen samples, not only for application in livestock but also for use in conducting assisted reproduction techniques in other species.


Assuntos
Sêmen , Motilidade dos Espermatozoides , Masculino , Feminino , Animais , Motilidade dos Espermatozoides/fisiologia , Gado , Fertilidade/fisiologia , Espermatozoides/fisiologia , Análise do Sêmen/veterinária , Análise do Sêmen/métodos
7.
Cells ; 10(6)2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203610

RESUMO

Estimating costs of ejaculate production is challenging. Metabolic investment in ejaculates may come at the expense of other physiological functions and may negatively affect future reproduction and/or survival. These trade-offs are especially likely to occur under constrained resource pools (e.g., poor nutrition). Here, we investigated costs of ejaculate production via trade-offs in the field cricket Gryllus bimaculatus. We experimentally increased rates of ejaculate production, while keeping an unmanipulated group, in adult males kept at high and low feeding regimes and tested the effects of our treatments on (i) somatic maintenance (i.e., changes in male body mass), (ii) future reproduction (i.e., the likelihood of producing a spermatophore and the viability of its sperm), and (iii) lifetime survival and longevity. We predicted investment in ejaculates to impinge upon all measured responses, especially in low-fed individuals. Instead, we only found negative effects of food limitation, suggesting low or undetectable costs of spermatophore production. High mating rates may select for males to maximize their capacity of ejaculate production, making ejaculate traits less prone to trade-offs with other fitness-related life history traits. Nevertheless, males were impaired due to nutrient deficiency in producing viable ejaculates, suggesting condition-dependent costs for ejaculate production.


Assuntos
Ingestão de Alimentos/fisiologia , Gryllidae/fisiologia , Reprodução/fisiologia , Animais , Ejaculação/fisiologia , Fertilidade/fisiologia , Gryllidae/metabolismo , Masculino , Nutrientes/metabolismo , Sêmen , Espermatozoides/fisiologia
8.
Ecotoxicol Environ Saf ; 207: 111219, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32931966

RESUMO

Contamination by organic and inorganic compounds remains one of the most complex problems in both brackish and marine environments, causing potential implications for the reproductive success and survival of several broadcast spawners. Ficopomatus enigmaticus is a tubeworm polychaete that has previously been used as a model organism for ecotoxicological analysis, due to its sensitivity and ecological relevance. In the present study, the effects of five trace elements (zinc, copper, cadmium, arsenic and lead), one surfactant (sodium dodecyl sulfate, SDS) and one polycyclic aromatic hydrocarbon (benzo(a)pyrene, B(a)P) on the sperm quality of F. enigmaticus were investigated. Sperm suspensions were exposed in vitro to different concentrations of each selected contaminant under four salinity conditions (10, 20, 30, 35). Possible adverse effects on sperm function were assessed by measuring oxidative stress, membrane integrity, viability and DNA damage. Sperm quality impairments induced by organic contaminants were more evident than those induced by inorganic compounds. SDS exerted the largest effect on sperm. In addition, F. enigmaticus sperm showed high tolerance to salinity variation, supporting the wide use of this species as a promising model organism for ecotoxicological assays. Easy and rapid methods on polychaete spermatozoids were shown to be effective as integrated sperm quality parameters or as an alternative analysis for early assessment of marine and brackish water pollution.


Assuntos
Poliquetos/fisiologia , Espermatozoides/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Arsênio/farmacologia , Bioensaio , Cádmio/toxicidade , Ecotoxicologia/métodos , Masculino , Poliquetos/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Salinidade , Oligoelementos/toxicidade
9.
Nagoya J Med Sci ; 82(4): 677-684, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33311798

RESUMO

We investigated the impact of prior anticancer treatments such as chemotherapy and radiotherapy on subsequent infertility treatment in cancer survivors who consulted our male infertility division. Of 1,525 male infertility patients who consulted our division between 2008 and 2018, 56 (3.7%) were cancer survivors. Of these, 32 received anticancer treatment (group A) and 24 were treated with surgery alone or were seen before anticancer treatment (group B). Semen analysis revealed that azoospermia in 26 subjects (81.3%) and 14 (58.3%) in groups A and B respectively. Ejaculatory dysfunction was observed 1 in group A and in 2 group B subjects. Sperm cryopreservation before anticancer treatment was performed 4 subjects. Sperm retrieval surgery for intracytoplasmic sperm injection (ICSI) was performed in 13 cases in group A and 10 in group B. Motile sperm were recovered in 7 subjects and in 8 subjects in group A and B respectively. Overall pregnancies and deliveries with ICSI were achieved for 7 subjects (21.9%) in group A, and 9 (37.5%) in group B. Successful sperm retrieval may not be affected by prior anticancer treatment as shown in this study. However, some patients abandoned infertility treatment due to the cost of testing and sperm retrieval surgery. Support for the cost of infertility treatment in cancer survivors is necessary.


Assuntos
Antineoplásicos , Preservação da Fertilidade/métodos , Infertilidade Masculina , Radioterapia , Recuperação Espermática , Espermatozoides , Adulto , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Sobreviventes de Câncer/estatística & dados numéricos , Custos e Análise de Custo , Criopreservação/métodos , Humanos , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/etiologia , Infertilidade Masculina/prevenção & controle , Japão/epidemiologia , Masculino , Avaliação das Necessidades , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Radioterapia/efeitos adversos , Radioterapia/métodos , Recuperação Espermática/economia , Recuperação Espermática/estatística & dados numéricos , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia
10.
Reprod Biol ; 20(4): 465-473, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32792216

RESUMO

Di-(2-ethylhexyl) phthalate is representative of Phthalate esters (PAEs), which is one of the most widely used plasticizer and known to act as a reproductive toxicant. However, little is known about the toxicity and pathological process of DEHP exposure in male reproductive system in terms of different concentrations and time points. In this study, peripubertal male Sprague Dawley rats were continually exposed to different DEHP doses (100 mg/kg, 500 mg/kg, and 900 mg/kg) and periods (7 days, 14 days, 21 days, 28 days, and 35 days) during critical periods for sexual maturity. The reproductive parameters have been investigated, including testicular morphology, serum testosterone level, and testicular P450scc, 3ß-HSD, and PCYP17 levels. We observed disarrangement of testicular spermatogenic epithelium coupled with decrease of serum testosterone, testicular P450scc, 3ß-HSD, and PCYP17 levels, and these changes were more obvious with increase of both the exposure time and dosage. Then trend of the time-dose response to DEHP exposure and the pathological process in germ cells were estimated. The results of this study suggested that DEHP exposure could affect the male reproductive system and the degree of adverse effect depended on the dose and extent of exposure.


Assuntos
Dietilexilftalato/toxicidade , Plastificantes/toxicidade , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , 3-Hidroxiesteroide Desidrogenases/análise , Animais , Enzima de Clivagem da Cadeia Lateral do Colesterol/análise , Dietilexilftalato/administração & dosagem , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Sprague-Dawley , Espermatozoides/fisiologia , Esteroide 17-alfa-Hidroxilase/análise , Testículo/química , Testículo/patologia , Testosterona/sangue , Fatores de Tempo
11.
Reprod Domest Anim ; 55(10): 1383-1392, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32722862

RESUMO

Viability assessment is an important part of semen analysis, and various live/dead staining protocols have been used in semen of avian species. Results of live/dead count differed between dyes, staining protocols and bird species, impeding comparability between studies and requiring species-specific comparisons of viability stains. In raptor semen, similar comparisons are absent. Thus, the aim of the present study was to compare eight conventional viability stains. Eosin blue 2% [EB], eosin blue 2% with the addition of 3% sodium citrate [EB2], eosin blue-nigrosin 5% [EBN5], eosin yellow-nigrosin 5% [EYN5], eosin yellow-nigrosin 10% [EYN10], eosin blue-aniline blue [EBA], eosin yellow-aniline blue [EYA] and bromophenol blue-nigrosin [BBN] were evaluated in comparison with the fluorescence stain SYBR® Green-propidium iodide [SYBR-PI] in spermatozoa of falcons. The comparison was performed using conventional light microscopy which is applicable in breeding centres, veterinary practices and field studies. Additionally, live/dead stains were correlated to motility values of the same samples to validate sperm viability. Light microscopy using EB and using SYBR-PI enabled an effective and clear differentiation between alive and dead spermatozoa of falcons. Motility values correlated significantly and strongly with EB only (r = .629; p < .001), but not with any other stain used in the study. Therefore, our results suggest EB as the most suitable stain for viability assessment in the semen of large falcons.


Assuntos
Falconiformes/fisiologia , Espermatozoides/fisiologia , Coloração e Rotulagem/veterinária , Animais , Sobrevivência Celular , Corantes , Masculino , Microscopia/veterinária , Análise do Sêmen/veterinária , Motilidade dos Espermatozoides , Coloração e Rotulagem/métodos
12.
J Evol Biol ; 33(9): 1294-1305, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32614995

RESUMO

Males of many species evolved the capability of adjusting their ejaculate phenotype in response to social cues to match the expected mating conditions. When females store sperm for a prolonged time, the expected fitness return of plastic adjustments of ejaculate phenotype may depend on the interval between mating and fertilization. Although prolonged female sperm storage (FSS) increases the opportunity for sperm competition, as a consequence of the longer temporal overlap of ejaculates from several males, it may also create variable selective forces on ejaculate phenotype, for example by exposing trade-offs between sperm velocity and sperm survival. We evaluated the relationship between the plasticity of ejaculate quality and FSS in the guppy, Poecilia reticulata, a polyandrous live-bearing fish in which females store sperm for several months and where stored sperm contribute significantly to a male's lifelong reproductive success. In this species, males respond to the perception of future mating opportunities by increasing the quantity (number) and quality (swimming velocity) of ready-to-use sperm (an anticipatory response called 'sperm priming'). Here we investigated (a) the effect of sperm priming on in vitro sperm viability at stripping and its temporal decline (as an estimate of sperm survival), and (b) the in vivo competitive fertilization success in relation to female sperm storage using artificial insemination. As expected, sperm-primed males produced more numerous and faster sperm, but with a reduced in vitro sperm viability at stripping and after 4 hr, compared with their counterparts. Artificial insemination revealed that the small (nonsignificant) advantage of primed sperm when fertilization immediately follows insemination is reversed when eggs are fertilized by female-stored sperm, weeks after insemination. By suggesting a plastic trade-off between sperm velocity and viability, these results demonstrate that prolonged female sperm storage generates divergent selection pressures on ejaculate phenotype.


Assuntos
Poecilia/fisiologia , Espermatozoides/fisiologia , Animais , Copulação , Feminino , Fertilização , Genitália Masculina/fisiologia , Masculino
13.
Reprod Fertil Dev ; 32(10): 914-922, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32586421

RESUMO

This study investigated the reproductive toxicity of methylmercury (MeHg) and Aroclor (Sigma-Aldrich), alone or in combination, following exposure of prepubertal male rats considering the chromatoid body (CB) as a potential target. The CB is an important molecular regulator of mammalian spermatogenesis, primarily during spermatid cytodifferentiation. Male Wistar rats were exposed to MeHg and/or Aroclor , according the following experimental design: control group, which was administered in corn oil (vehicle) only; MeHg-treated group, which was administered 0.5mg kg-1 day-1 MeHg; Aroclor-treated group, which was administered 1mg kg-1 day-1 Aroclor; Mix-LD, group which was administered a low-dose mixture of MeHg (0.05mg kg-1 day-1) and Aroclor (0.1mg kg-1 day-1); and Mix-HD group, which was administered a high-dose mixture of MeHg (0.5mg kg-1 day-1) and Aroclor (1.0mg kg-1 day-1). MeHg was diluted in distilled water and Aroclor was made up in corn oil (volume 1mL kg-1). Rats were administered the different treatments from PND23 to PND53 by gavage, . The morphophysiology of CBs was analysed, together with aspects of steroid hormones status and regulation, just after the last treatment on PND53. In addition, the long-term effects on sperm parameters were assessed in adult animals. MeHg exposure increased mouse VASA homologue (MVH) protein levels in seminiferous tubules, possibly affecting the epigenetic status of germ cells. Aroclor produced morphological changes to CB assembly, which may explain the observed morphological defects to the sperm flagellum and the consequent decrease in sperm motility. There were no clear additive or synergistic effects between MeHg and Aroclor when administered in combination. In conclusion, this study demonstrates that MeHg and Aroclor have independent deleterious effects on the developing testis, causing molecular and morphological changes in CBs. To the best of our knowledge, this is the first study to show that CBs are targets for toxic agents.


Assuntos
Arocloros/toxicidade , Grânulos Citoplasmáticos/efeitos dos fármacos , Compostos de Metilmercúrio/toxicidade , Reprodução/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Espermatozoides/ultraestrutura , Animais , Grânulos Citoplasmáticos/metabolismo , Grânulos Citoplasmáticos/ultraestrutura , Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , Ratos , Ratos Wistar , Túbulos Seminíferos/efeitos dos fármacos , Túbulos Seminíferos/metabolismo , Maturidade Sexual , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/anormalidades , Espermatozoides/fisiologia , Testículo/efeitos dos fármacos , Testículo/crescimento & desenvolvimento
14.
Theory Biosci ; 139(3): 235-251, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32488752

RESUMO

Swimming of spermatozoa through couple stress fluid in an asymmetric human cervical canal is investigated in the present theoretical analysis. A couple of fourth-order partial differential equations arising from the mathematical modelling of the proposed model is solved analytically. Flow variables like pressure gradient, propulsive velocity, mucus velocity and time mean flow rate are analysed for the pertinent parameters. Conspicuous features of the pumping characteristics are explored. It is found that pressure rise facilitates the motion of spermatozoa to fertilize an ovum in the female reproductive tract, whereas pressure drop by inverting the direction of spermatozoa controls the probability of pregnancy. Maximal propulsive velocity of the spermatozoa is reported in the absence of travelling waves along the cervical walls. Minute impact of phase difference on propulsive velocity is evident. An analogy of the current analysis with the existing literature is also made.


Assuntos
Colo do Útero/anormalidades , Colo do Útero/metabolismo , Espermatozoides/metabolismo , Muco do Colo Uterino , Feminino , Fertilização , Células Caliciformes , Humanos , Masculino , Modelos Biológicos , Modelos Teóricos , Movimento (Física) , Muco , Pressão , Reologia , Espermatozoides/fisiologia , Viscosidade
16.
J Anim Breed Genet ; 137(2): 189-199, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31515873

RESUMO

Accurate predictive modelling facilitates efficient and effective trait selection in animal breeding and can decrease costs while maximizing profits when raising economically important animals. The objective of this study was to extend a previously developed bioeconomic model and computer program to calculate the marginal economic values (MEVs) and economic weights (EWs) for direct and maternal pig traits affected by new reproductive traits, namely the number of sow functional teats (NFTs) and boar sperm quality traits (SQTs) that included sperm volume, sperm concentration, motility percentage and percentage of abnormal spermatozoa. The MEV of NFTs represented the cost differences between naturally and artificially reared piglets until weaning and the cost differences between naturally and artificially reared finished animals. The MEVs of SQTs expressed the saved costs for artificial insemination, assuming a decreased price per insemination dose when improving the SQTs. The absolute and relative EWs for the newly defined complex of traits in the breeding objectives for pig breeds involved in the Czech national three-way crossing system (Czech Large White [CLW], Czech Landrace [CL] and Pietrain [PN]) were calculated using gene flow methods. The NFT trait was included only for dam breeds, and the relative EW averaged 3.6% of the total economic importance based on the genetic standard deviations of all 19 simultaneously evaluated traits in CLW and CL breeds. The relative EWs of the four SQTs comprised 2.0% of the total economic importance of the 19 traits in the CLW and CL dam breeds and 8% of the total economic importance of the 18 traits in the PN sire breed. Therefore, inclusion of the NFTs for dam breeds and SQTs for sire breeds in the breeding goal is recommended to aid in obtaining ideal outcomes with optimal economic values.


Assuntos
Cruzamento/economia , Glândulas Mamárias Animais , Fenótipo , Espermatozoides , Suínos/genética , Criação de Animais Domésticos/economia , Animais , Feminino , Fluxo Gênico , Masculino , Glândulas Mamárias Animais/fisiologia , Modelos Econômicos , Reprodução/genética , Seleção Genética , Espermatozoides/fisiologia , Suínos/fisiologia
17.
Anim Reprod Sci ; 210: 106176, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31635773

RESUMO

The Black Crested Mangabey (Lophocebus aterrimus) is an African monkey listed as Near Threatened by the IUCN and in captivity the population is limited to 34 males. The aim of this study was to evaluate two Black Crested Mangabey males, maintained in captivity in a zoological garden and suspected of infertility, with a complete examination of their genital tract using ultrasonography, followed by recovery of semen using transrectal ultrasonic massage of the accessory sexual glands (TUMASG) and electroejaculation. One male had small testicular and accessory sex gland sizes indicative of senile hypoplasia. The other male was suspected of infertility. Four semen samples were obtained. Fresh semen was initially evaluated, diluted in Refrigeration Medium Test Yolk buffer, cooled at 15 °C and cryopreserved. Endocrine profiles (testosterone, oestradiol, FSH, LH, cortisol), prostatic specific antigen and semen variables (volume, concentration, motility by CASA, viability and acrosome status using flow cytometry, morphology, morphometry utilising TEM) were evaluated in raw, cooled and cryopreserved samples. There was no detrimental effect of cooling or cryopreservation on sperm viability and acrosomal integrity. Similar percentages of viable and acrosome-intact spermatozoa were present in cooled (for 6 h) and frozen-thawed semen samples (75.1% compared with 69.0%, P > 0.05), while progressive motility was greater in cooled, compared with frozen-thawed samples (81.5% compared with 67.3%). This study was the first in which there was evaluation of sperm variables in this species and, although this study is limited by the number of animals it provides background information for further studies using assisted reproductive technologies.


Assuntos
Cercopithecus/fisiologia , Estimulação Elétrica/métodos , Genitália Masculina , Espermatozoides/fisiologia , Ultrassom , Animais , Criopreservação/veterinária , Congelamento , Masculino , Preservação do Sêmen
18.
Regul Toxicol Pharmacol ; 108: 104479, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31539566

RESUMO

Sunset Yellow FCF was tested for 28-days in male Hsd:SD® rats for its potential effect on sperm quality parameters at dietary concentrations of 6,000, 12,000 and 18,000 ppm, corresponding to target doses of 500, 1000, and 1500 mg/kg bw/day. The measured average daily intake was 490, 944, and 1,475 mg/kg bw/day, based on feed consumption and stability of Sunset Yellow FCF in the diet. The animals fed diets with Sunset Yellow FCF presented no clinical signs of toxicity and no differences in feed consumption, body weights, organ weights, ophthalmology, hematology, clinical chemistry, urinalysis, or coagulation parameters that were considered adverse. No mortality or abnormalities were observed at necropsy, and no microscopic changes were observed in histopathology. Increased testes weights relative to body weight in animals of the middle and high intake groups were not associated with any abnormal findings in histopathology. Sperm quality evaluation presented no adverse effects on sperm motility, epididymal sperm count, homogenization-resistant spermatid count, or sperm morphological development. Therefore, in the absence of any adverse effects under the conditions of this study, the NOAEL for Sunset Yellow FCF was 1,475 mg/kg bw/day in male rats, corresponding to 18,000 ppm in the diet.


Assuntos
Compostos Azo/toxicidade , Corantes de Alimentos/toxicidade , Espermatozoides/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Masculino , Nível de Efeito Adverso não Observado , Ratos Sprague-Dawley , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia
19.
J Evol Biol ; 32(11): 1300-1309, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31465604

RESUMO

In Drosophila, long sperm are favoured in sperm competition based on the length of the female's primary sperm storage organ, the seminal receptacle (SR). This sperm-SR interaction, together with a genetic correlation between the traits, suggests that the coevolution of exaggerated sperm and SR lengths may be driven by Fisherian runaway selection. Here, we explore the costs and benefits of long sperm and SR genotypes, both in the sex that carries them and in the sex that does not. We measured male and female fitness in inbred lines of Drosophila melanogaster derived from four populations previously selected for long sperm, short sperm, long SRs or short SRs. We specifically asked: What are the costs and benefits of long sperm in males and long SRs in females? Furthermore, do genotypes that generate long sperm in males or long SRs in females impose a fitness cost on the opposite sex? Answers to these questions will address whether long sperm are an honest indicator of male fitness, male post-copulatory success is associated with male precopulatory success, female choice benefits females or is costly, and intragenomic conflict could influence evolution of these traits. We found that both sexes have increased longevity in long sperm and long SR genotypes. Males, but not females, from long SR lines had higher fecundity. Our results suggest that sperm-SR coevolution is facilitated by both increased viability and indirect benefits of long sperm and SRs in both sexes.


Assuntos
Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Espermatozoides/citologia , Espermatozoides/fisiologia , Animais , Evolução Biológica , Masculino , Preferência de Acasalamento Animal/fisiologia , Comportamento Sexual Animal/fisiologia
20.
J Obstet Gynaecol Can ; 41(9): 1338-1340, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31345737

RESUMO

Commercial gamete donation in Canada is prohibited by the Assisted Human Reproduction Act. However, the Act permits gamete recipients to reimburse donors for donation-related expenses. Until recently, the types of expenses that were eligible and the process for reimbursing donors were not specified. In 2016, Health Canada announced its intent to develop regulations that would regulate gamete donor reimbursement; it released the proposed policy in 2017. As a result of consultations with Canadian lawmakers, physicians, and patients, debates surrounding commercial gamete donation are being revisited. Considering the ethical implications of gamete donation payment arrangements, a patient-centred care framework is useful going forward in the regulation of this practice. Patient-centred values of communication, respecting relational autonomy, and respecting patient interests should guide decisions regarding regulation of gamete donation arrangements in Canada.


Assuntos
Óvulo , Espermatozoides , Doadores de Tecidos/legislação & jurisprudência , Canadá , Feminino , Humanos , Masculino , Óvulo/citologia , Óvulo/fisiologia , Assistência Centrada no Paciente/legislação & jurisprudência , Mecanismo de Reembolso , Espermatozoides/citologia , Espermatozoides/fisiologia
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