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1.
Arch Razi Inst ; 75(4): 484-490, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33403843

RESUMO

The specific changes in antral follicle numbers and wave-like development have remained unrevealed in cyclic ewes fed high-protein, high-energy lupin grain for 6 days during the luteal phase of the estrous cycle (i.e., short-term nutritional flushing). This study was mainly conducted to determine ovarian effects of the 6-day lupin grain feeding in non-prolific Polish Mountain ewes, using transrectal ovarian ultrasonography and abdominal videoendoscopy. Estrus and ovulations were synchronized in 24 ewes with progestin-releasing intravaginal sponges for 12 days during the middle portion of the breeding season (September-October; 50.0458°N, 19.8406°E). Twenty-four ewes were assigned to three equal groups (n=8 each), including the Control group being fed the maintenance diet (i.e., hay-only), Treatment 1 receiving 500 g of lupin grain once a day, and Treatment 2 receiving 250 g of lupin grain twice a day, from days 9-14 of the synchronized estrous cycle (day 0=first ovulation of the interovulatory period studied). No differences were observed in the mean ovulation rate among the three groups of Polish Mountain ewes (P>0.05). Ovarian antral follicles emerging in the penultimate wave of the estrous cycle in Treatment 2 ewes had a longer growth phase (p <0.05) and attained a greater diameter (p <0.05) before ovulation, in comparison to those in the other two groups. A final wave of the interovulatory interval emerged ~1 day earlier in Treatment 2 than in Treatment 1 ewes (p <0.05). Nutritional supplementation with lupin grain increased the number of 3-mm follicles in Treatment 2 ewes (p <0.05). The results of this study indicated that short-term nutritional flushing with lupin grain from mid- to late luteal phase did not consistently enhance ovulatory responses in non-prolific genotypes of ewes. Although the administration of lupins altered the timing of wave emergence, ovulatory follicle diameter, or duration of different stages of the follicular lifespan, it failed to increase the number of ovulatory follicles emerging in the penultimate and final waves of the estrous cycle in non-prolific Polish Mountain sheep.


Assuntos
Suplementos Nutricionais/análise , Lupinus/química , Ovário/fisiologia , Ovulação , Carneiro Doméstico/fisiologia , Ração Animal/análise , Animais , Corpo Lúteo/efeitos dos fármacos , Corpo Lúteo/crescimento & desenvolvimento , Dieta/veterinária , Relação Dose-Resposta a Droga , Feminino , Histeroscopia/veterinária , Fase Luteal , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/crescimento & desenvolvimento , Ovário/diagnóstico por imagem , Ovário/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Polônia , Estações do Ano , Sementes/química , Ultrassonografia/veterinária
2.
J Comp Physiol B ; 190(1): 17-26, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31720761

RESUMO

Stressed animals often struggle to maintain optimal investment into a number of fitness-related traits, which can result in some traits being more adversely affected than others. Variation in stress-related costs may also depend on the environment-costs can be facultative and only occur when resources are limited, or they may be obligate and occur regardless of resource availability. Dynamics of oxidative stress may be important in life-history evolution given their role in a range of biological processes-from reproduction to immunity to locomotion. Thus, we examined how resource (food) availability influences the costs of oxidative challenge to fitness-related traits spanning several levels of biological organization. We manipulated food availability and oxidative status in females of the wing-dimorphic sand field cricket (Gryllus firmus) during early adulthood. We then determined investment into several traits: reproduction (ovary mass), soma (body mass and flight musculature), and immune function (total phenoloxidase activity). Oxidative challenge (paraquat exposure) obligated costs to somatic tissue and a parameter of immune function regardless of food availability, but it did not affect reproduction. We show that the costs of oxidative challenge are trait-specific, but we did not detect a facultative (food-dependent) cost of oxidative challenge to any trait measured. Although the dynamics of oxidative stress are complex, our study is an important step toward a more complete understanding of the roles that resource availability and redox systems play in mediating life histories.


Assuntos
Gryllidae/fisiologia , Asas de Animais/fisiologia , Animais , Evolução Biológica , Feminino , Fertilidade , Gryllidae/enzimologia , Monofenol Mono-Oxigenase/metabolismo , Ovário/fisiologia , Estresse Oxidativo , Reprodução , Asas de Animais/enzimologia
3.
Mech Dev ; 160: 103582, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31634535

RESUMO

Important aspects of vertebrate reproduction, such as gametogenesis, involve changes in organs found deep internally and thus not easily studied directly in most living vertebrates due to obscuring pigment and overlying tissues. Transparent lines of zebrafish, especially the Casper double mutant, allow direct observation and analysis of reproductive events in the gonads in vivo. The natural production of fertilized eggs in zebrafish is a complex process involving oogenesis, spermatogenesis, mating behavior, endocrine and neurological processes with inputs from the environment including light, temperature and nutrition. While these factors play important roles, the hypothalamic-pituitary-gonadal axis (HPGA) is central in the regulation of embryo output. Endocrine disrupting compounds (EDCs) include a variety of pollutants often present in the environment. EDCs may have direct effects on the HPGA or indirect effects through toxic action on supporting organs such as the liver or kidney. Estrogenic compounds such as diethylstilbestrol (DES) have been reported to affect reproduction in a variety of species including man. In this study, the effects of DES on reproduction were determined in a novel way by using transparent Casper zebrafish that allow direct visualization of gonad status over time. Changes in gonad status with DES treatment were correlated with effects on secondary sex characteristics (i.e., genital vent size and breeding tubercles) spawning and embryo production. The results suggest that the Casper zebrafish is a useful model for studying dynamics of reproductive events in vertebrate gonads in vivo and for determining effects of EDCs on zebrafish reproduction.


Assuntos
Gônadas/fisiologia , Reprodução/fisiologia , Caracteres Sexuais , Peixe-Zebra/fisiologia , Animais , Dietilestilbestrol/farmacologia , Feminino , Gônadas/anatomia & histologia , Gônadas/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ovário/efeitos dos fármacos , Ovário/fisiologia , Reprodução/efeitos dos fármacos , Testículo/anatomia & histologia , Testículo/efeitos dos fármacos
4.
Artigo em Inglês | MEDLINE | ID: mdl-30420162

RESUMO

This chapter describes ovarian anatomy and embryology in humans. The formation of the ovarian reserve is discussed, and events of folliculogenesis are described, including description of developmental events in primordial, primary, secondary, antral and periovulatory follicles. Paracrine and autocrine factors play critical roles in oocyte maturation and follicular development, and research related to the hypothesised roles of individual factors is discussed. Gonadotrophin-dependent events relating to dominant follicle selection are discussed. The two-cell, two-gonadotrophin hypothesis of ovarian steroidogenesis is explained. The clinical role of AMH is outlined. Premature ovarian failure and known associated aetiological factors are described. In the conclusion, with an understanding of the principle events of ovarian folliculogenesis, the follicular wave theory is described, and it is explained how adaptation of ovarian stimulation regimens may achieve time-efficient fertility preservation treatment options for patients with cancer.


Assuntos
Folículo Ovariano/fisiologia , Reserva Ovariana/fisiologia , Ovário/fisiologia , Hormônio Antimülleriano/fisiologia , Feminino , Preservação da Fertilidade , Humanos , Indução da Ovulação , Insuficiência Ovariana Primária/fisiopatologia
5.
Cryobiology ; 82: 118-123, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29596843

RESUMO

Vitrification of ovarian tissue containing immature oocytes provides an important tool for protecting the endangered species and genetic diversity in aquatic species. Therefore, the main objective was to assess primary growth (PG) oocytes viability following ovarian tissue vitrification using histological analysis, two staining protocols (trypan blue or fluorescein diacetate combined with propidium iodide) and mitochondrial activity assay (MTT assay). In addition, oocyte histomorphometry was performed to evaluate the morphometric parameters after vitrification and the relationship with the occurrence of damage (nucleus and/or membrane) in PG oocytes. There was no significant difference among the vitrified oocytes using trypan blue dye or FDA + IP staining. Oocyte viability assessed using histological analysis showed that vitrification solution 2.0 M Me2SO + 2.5 M etilenoglycol +0.5 M sucrose (VS3; 66.43 ± 4.68%) and 1.5 M methanol + 5.5 M Me2SO + 0.5 M sucrose (VS5; 74.14 ± 3.71%) had the lowest viability rate. Similar results were observed in MTT assay where VS3 (1.63 ± 0.12) and VS5 (1.58 ± 0.09) had the lowest averages when compare with VS1 (2.39 ± 0.14), VS2 (1.78 ± 0.06) and VS4 (2.34 ± 0.19) (P = 0.0002). In membrane damage evaluation by histology, there was no difference among vitrified oocytes and control. However, the highest percentages of nucleus damage were observed in treatments VS3 (26.00 ± 5.55) and VS5 (26.00 ± 5.55). Oocyte diameter did not change after vitrification; however, nucleus diameter was significantly higher in control group (49.03 ± 1.07). Oocyte viability by histological analysis was positive-correlated to the occurrence of nucleus (r2 = 0.78) and membrane (r2 = 0.45) damage after vitrification/warming. The high viability of PG oocytes obtained after ovarian tissue vitrification of Piaractus mesopotamicus suggests that the protocol applied here might be used successfully in other teleost species for food production.


Assuntos
Membrana Celular/fisiologia , Núcleo Celular/fisiologia , Caraciformes/embriologia , Criopreservação/métodos , Oócitos/crescimento & desenvolvimento , Ovário/fisiologia , Vitrificação , Animais , Sobrevivência Celular , Feminino , Metanol/farmacologia , Mitocôndrias/metabolismo , Sacarose/farmacologia
6.
Theriogenology ; 113: 192-196, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29550492

RESUMO

Research on reproduction and fertility is an essential fundament of management strategies in European wild boar. Concerning the examination of the reproductive tract, methods still lack conformity and comparability. So far the reproductive status of female wild boar has been assessed by ovarian macroscopic examination. In order to find out if this is a valid method, 21 ovaries of 8-34 months old animals covering (early) follicular phase and cyclic inactivity were evaluated microscopically. Number and dimension of follicles as well as the occurrence of atretic follicles were compared and related to age, weight, ovary weight and size of ovary. For this study, 21 ovaries of the right side of each animal were weighed and measured. The diameter of the functional bodies was measured and functional bodies were counted. Size of ovary was calculated by length*width*height (cm3). Macroscopically, follicles were classified into four categories by diameter: F1 (0.2-0.3 cm), F2 (0.4-0.5 cm), F3 (0.6-0.8 cm) and F4 (0.9-1.3 cm). Microscopically, antral follicles of every 10th slice per section of each ovary were counted and classified into three categories by diameter: F0 (≥2 mm), FS (1-2 mm) and FXS (≤1 mm). In follicles with a diameter greater than 2 mm (F0), length and width were measured from the beginning of theca interna. Results showed that age and weight of wild boars were highly correlated (cor = 0.845, p < 0.001). Wild boar of higher age and weight showed higher ovary weight, but this was not significant (p = 0.135 (age), p = 0.329 (weight)). Although the number of macroscopically seen follicles differed widely by animal, microscopically only one ovary showed only small tertiary follicles. Animals with bigger follicles showed a significantly (p = 0.006) smaller number of small and smallest tertiary follicles. The number of tertiary follicles (F0) was not significantly influenced by age or carcass weight (p = 0.460, 0.159). Older and heavier animals showed significantly less FX and FXS (p < 0.001). Comparison of the follicular composition of young wild boar ovaries with domestic pig research allows the conclusion that assessment of cyclic activity and near puberty is possible. However, due to the fact that puberty is a long term biological progress, defining the time of sexual maturity will always be an estimate. Nevertheless, microscopic examination confirmed the macroscopic findings, including follicular dimensions and developmental stage allowing the conclusion that macroscopic evaluation of ovarian functional bodies in wild boar is an easy and reliable way to assess reproductive performance.


Assuntos
Ovário/anatomia & histologia , Reprodução/fisiologia , Sus scrofa/fisiologia , Animais , Feminino , Ovário/fisiologia , Estações do Ano , Maturidade Sexual
7.
Med Sci Monit ; 24: 1152-1157, 2018 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-29476685

RESUMO

BACKGROUND This study aimed to investigate ovarian reserve in patients of reproductive age with Celiac disease (CD) using anti-Müllerian hormone (AMH) levels, antral follicle counts (AFCs), and ovarian volume. MATERIAL AND METHODS We included into this study 46 CD female patients and 40 healthy female subjects of reproductive age, ages 18-45 years. Venous blood samples were taken from both groups on days 2-4 of the menstrual cycle, and follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), prolactin (PRL), and AMH levels were measured. On the same day, AFCs and ovarian volumes were determined. Data on body mass index (BMI), gravidity/parity/abortions/alive counts, disease duration, and Marsh histological classification were recorded. RESULTS There were no statistically significant differences between CD and control groups in terms of mean age, BMI, or median gravidity/parity/abortions/alive counts (p>0.05). Also, there were no statistically significant differences between the 2 groups in terms of mean FSH, LH, E2, PRL levels, right and left ovarian volumes, and median right and left ovarian AFCs (p>0.05). However, AMH level was significantly lower in the CD group (p=0.032). No statistically significant correlation was found between AMH levels and age, BMI, FSH, LH, E2, PRL levels, right and left ovarian volumes, right and left ovarian AFCs, or Marsh histological classification using the Spearman correlation test (p>0.05). However, an inverse correlation was detected showing that AMH levels decrease with increasing CD duration (r=-0.054, p=0.001). CONCLUSIONS We found that AMH level and ovarian reserve was decreased in CD patients of reproductive age compared to healthy controls, and that AMH level and ovarian reserve decreased with increasing disease duration in CD patients.


Assuntos
Doença Celíaca/fisiopatologia , Reserva Ovariana/fisiologia , Ovário/fisiologia , Adolescente , Adulto , Hormônio Antimülleriano/análise , Hormônio Antimülleriano/sangue , Pesos e Medidas Corporais , Doença Celíaca/complicações , Estradiol/análise , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/análise , Hormônio Foliculoestimulante/sangue , Número de Gestações , Humanos , Hormônio Luteinizante/análise , Hormônio Luteinizante/sangue , Pessoa de Meia-Idade , Folículo Ovariano/citologia , Paridade , Gravidez
8.
Hum Reprod ; 32(12): 2506-2514, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29121269

RESUMO

STUDY QUESTION: Does a reduced FSH dose in women with a predicted hyper response, apparent from a high antral follicle count (AFC), who are scheduled for IVF/ICSI lead to a different outcome with respect to cumulative live birth rate and safety? SUMMARY ANSWER: Although in women with a predicted hyper response (AFC > 15) undergoing IVF/ICSI a reduced FSH dose (100 IU per day) results in similar cumulative live birth rates and a lower occurrence of any grade of ovarian hyperstimulation syndrome (OHSS) as compared to a standard dose (150 IU/day), a higher first cycle cancellation rate and similar severe OHSS rate were observed. WHAT IS KNOWN ALREADY: Excessive ovarian response to controlled ovarian stimulation (COS) for IVF/ICSI may result in increased rates of cycle cancellation, the occurrence of OHSS and suboptimal live birth rates. In women scheduled for IVF/ICSI, an ovarian reserve test (ORT) can be used to predict response to COS. No consensus has been reached on whether ORT-based FSH dosing improves effectiveness and safety in women with a predicted hyper response. STUDY DESIGN SIZE, DURATION: Between May 2011 and May 2014, we performed an open-label, multicentre RCT in women with regular menstrual cycles and an AFC > 15. Women with polycystic ovary syndrome (Rotterdam criteria) were excluded. The primary outcome was ongoing pregnancy achieved within 18 months after randomization and resulting in a live birth. Secondary outcomes included the occurrence of OHSS and cost-effectiveness. Since this RCT was embedded in a cohort study assessing over 1500 women, we expected to randomize 300 predicted hyper responders. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women with an AFC > 15 were randomized to an FSH dose of 100 IU or 150 IU/day. In both groups, dose adjustment was allowed in subsequent cycles (maximum 25 IU in the reduced and 50 IU in the standard group) based on pre-specified criteria. Both effectiveness and cost-effectiveness were evaluated from an intention-to-treat perspective. MAIN RESULTS AND THE ROLE OF CHANCE: We randomized 255 women to a daily FSH dose of 100 IU and 266 women to a daily FSH dose of 150 IU. The cumulative live birth rate was 66.3% (169/255) in the reduced versus 69.5% (185/266) in the standard group (relative risk (RR) 0.95 [95%CI, 0.85-1.07], P = 0.423). The occurrence of any grade of OHSS was lower after a lower FSH dose (5.2% versus 11.8%, RR 0.44 [95%CI, 0.28-0.71], P = 0.001), but the occurrence of severe OHSS did not differ (1.3% versus 1.1%, RR 1.25 [95%CI, 0.38-4.07], P = 0.728). As dose reduction was not less expensive (€4.622 versus €4.714, delta costs/woman €92 [95%CI, -479-325]), there was no dominant strategy in the economic analysis. LIMITATIONS, REASONS FOR CAUTION: Despite our training programme, the AFC might have suffered from inter-observer variation. Although strict cancellation criteria were provided, selective cancelling in the reduced dose group (for poor response in particular) cannot be excluded as observers were not blinded for the FSH dose and small dose adjustments were allowed in subsequent cycles. However, as first cycle live birth rates did not differ from the cumulative results, the open design probably did not mask a potential benefit for the reduced dosing group. As this RCT was embedded in a larger cohort study, the power in this study was unavoidably lower than it should be. Participants had a relatively low BMI from an international perspective, which may limit generalization of the findings. WIDER IMPLICATIONS OF THE FINDINGS: In women with a predicted hyper response scheduled for IVF/ICSI, a reduced FSH dose does not affect live birth rates. A lower FSH dose did reduce the incidence of mild and moderate OHSS, but had no impact on severe OHSS. Future research into ORT-based dosing in women with a predicted hyper response should compare various safety management strategies and should be powered on a clinically relevant safety outcome while assessing non-inferiority towards live birth rates. STUDY FUNDING/COMPETING INTEREST(S): This trial was funded by The Netherlands Organization for Health Research and Development (ZonMW, Project Number 171102020). SCO, TCvT and HLT received an unrestricted research grant from Merck Serono (the Netherlands). CBL receives grants from Merck, Ferring and Guerbet. BWJM is supported by a NHMRC Practitioner Fellowship (GNT1082548) and reports consultancy for OvsEva, Merck and Guerbet. FJMB receives monetary compensation as a member of the external advisory board for Ferring pharmaceutics BV and Merck Serono for consultancy work for Gedeon Richter (Belgium) and Roche Diagnostics (Switzerland) and for a research cooperation with Ansh Labs (USA). All other authors have nothing to declare. TRIAL REGISTRATION NUMBER: Registered at the ICMJE-recognized Dutch Trial Registry (www.trialregister.nl). Registration number: NTR2657. TRIAL REGISTRATION DATE: 20 December 2010. DATE OF FIRST PATIENT'S ENROLMENT: 12 May 2011.


Assuntos
Fertilização in vitro/métodos , Hormônio Foliculoestimulante/administração & dosagem , Folículo Ovariano/fisiologia , Ovário/fisiologia , Injeções de Esperma Intracitoplásmicas/métodos , Adulto , Coeficiente de Natalidade , Criopreservação , Feminino , Fertilização in vitro/economia , Hormônio Liberador de Gonadotropina/administração & dosagem , Humanos , Infertilidade/terapia , Variações Dependentes do Observador , Síndrome de Hiperestimulação Ovariana , Reserva Ovariana/efeitos dos fármacos , Indução da Ovulação/métodos , Segurança do Paciente , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Estudos Prospectivos , Injeções de Esperma Intracitoplásmicas/economia , Fatores de Tempo , Resultado do Tratamento
9.
Hum Reprod ; 32(12): 2496-2505, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29121326

RESUMO

STUDY QUESTION: Does an increased FSH dose result in higher cumulative live birth rates in women with a predicted poor ovarian response, apparent from a low antral follicle count (AFC), scheduled for IVF or ICSI? SUMMARY ANSWER: In women with a predicted poor ovarian response (AFC < 11) undergoing IVF/ICSI, an increased FSH dose (225/450 IU/day) does not improve cumulative live birth rates as compared to a standard dose (150 IU/day). WHAT IS KNOWN ALREADY: In women scheduled for IVF/ICSI, an ovarian reserve test (ORT) can predict ovarian response to stimulation. The FSH starting dose is often adjusted based on the ORT from the belief that it will improve live birth rates. However, the existing RCTs on this topic, most of which show no benefit, are underpowered. STUDY DESIGN, SIZE, DURATION: Between May 2011 and May 2014, we performed an open-label multicentre RCT in women with an AFC < 11 (Dutch Trial Register NTR2657). The primary outcome was ongoing pregnancy achieved within 18 months after randomization and resulting in a live birth. We needed 300 women to assess whether an increased dose strategy would increase the cumulative live birth rate from 25 to 40% (two-sided alpha-error 0.05, power 80%). PARTICIPANTS/MATERIALS, SETTING, METHODS: Women with an AFC ≤ 7 were randomized to an FSH dose of 450 IU/day or 150 IU/day, and women with an AFC 8-10 were randomized to 225 IU or 150 IU/day. In the standard group, dose adjustment was allowed in subsequent cycles based on pre-specified criteria. Both effectiveness and cost-effectiveness of the strategies were evaluated from an intention-to-treat perspective. MAIN RESULTS AND THE ROLE OF CHANCE: In total, 511 women were randomized, 234 with an AFC ≤ 7 and 277 with an AFC 8-10. The cumulative live birth rate for increased versus standard dosing was 42.4% (106/250) versus 44.8% (117/261), respectively [relative risk (RR): 0.95 (95%CI, 0.78-1.15), P = 0.58]. As an increased dose strategy was more expensive [delta costs/woman: €1099 (95%CI, 562-1591)], standard FSH dosing was the dominant strategy in our economic analysis. LIMITATIONS, REASONS FOR CAUTION: Despite our training programme, the AFC might have suffered from inter-observer variation. As this open study permitted small dose adjustments between cycles, potential selective cancelling of cycles in women treated with 150 IU could have influenced the cumulative results. However, since first cycle live birth rates point in the same direction we consider it unlikely that the open design masked a potential benefit for the individualized strategy. WIDER IMPLICATIONS OF THE FINDINGS: Since an increased dose in women scheduled for IVF/ICSI with a predicted poor response (AFC < 11) does not improve live birth rates and is more expensive, we recommend using a standard dose of 150 IU/day in these women. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by The Netherlands Organisation for Health Research and Development (ZonMW number 171102020). T.C.T., H.L.T. and S.C.O. received an unrestricted personal grant from Merck BV. H.R.V. receives monetary compensation as a member on an external advisory board for Ferring pharmaceutical BV. B.W.J.M. is supported by a NHMRC Practitioner Fellowship (GNT1082548) and reports consultancy for OvsEva, Merck and Guerbet. F.J.M.B. receives monetary compensation as a member of the external advisory board for Ferring pharmaceutics BV (the Netherlands) and Merck Serono (the Netherlands) for consultancy work for Gedeon Richter (Belgium) and Roche Diagnostics on automated AMH assay development (Switzerland) and for a research cooperation with Ansh Labs (USA). All other authors have nothing to declare. TRIAL REGISTRATION NUMBER: Registered at the ICMJE-recognized Dutch Trial Registry (www.trialregister.nl). Registration number NTR2657. TRIAL REGISTRATION DATE: 20 December 2010. DATE OF FIRST PATIENT'S ENROLMENT: 12 May 2011.


Assuntos
Fertilização in vitro/métodos , Hormônio Foliculoestimulante/administração & dosagem , Folículo Ovariano/fisiologia , Ovário/fisiologia , Injeções de Esperma Intracitoplásmicas/métodos , Adulto , Coeficiente de Natalidade , Criopreservação , Feminino , Fertilização in vitro/economia , Hormônio Liberador de Gonadotropina/administração & dosagem , Humanos , Infertilidade/terapia , Reserva Ovariana/efeitos dos fármacos , Indução da Ovulação/métodos , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Estudos Prospectivos , Injeções de Esperma Intracitoplásmicas/economia , Fatores de Tempo , Resultado do Tratamento
10.
Hum Reprod ; 32(12): 2485-2495, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29121350

RESUMO

STUDY QUESTION: Is there a difference in live birth rate and/or cost-effectiveness between antral follicle count (AFC)-based individualized FSH dosing or standard FSH dosing in women starting IVF or ICSI treatment? SUMMARY ANSWER: In women initiating IVF/ICSI, AFC-based individualized FSH dosing does not improve live birth rates or reduce costs as compared to a standard FSH dose. WHAT IS KNOWN ALREADY: In IVF or ICSI, ovarian reserve testing is often used to adjust the FSH dose in order to normalize ovarian response and optimize live birth rates. However, no robust evidence for the (cost-)effectiveness of this practice exists. STUDY DESIGN, SIZE, DURATION: Between May 2011 and May 2014 we performed a multicentre prospective cohort study with two embedded RCTs in women scheduled for IVF/ICSI. Based on the AFC, women entered into one of the two RCTs (RCT1: AFC < 11; RCT2: AFC > 15) or the cohort (AFC 11-15). The primary outcome was ongoing pregnancy achieved within 18 months after randomization resulting in a live birth (delivery of at least one live foetus after 24 weeks of gestation). Data from the cohort with weight 0.5 were combined with both RCTs in order to conduct a strategy analysis. Potential half-integer numbers were rounded up. Differences in costs and effects between the two treatment strategies were compared by bootstrapping. PARTICIPANTS/MATERIALS, SETTING, METHODS: In both RCTs women were randomized to an individualized (RCT1:450/225 IU, RCT2:100 IU) or standard FSH dose (150 IU). Women in the cohort all received the standard dose (150 IU). Anti-Müllerian hormone (AMH) was measured to assess AMH post-hoc as a biomarker to individualize treatment. For RCT1 dose adjustment was allowed in subsequent cycles based on pre-specified criteria in the standard group only. For RCT2 dose adjustment was allowed in subsequent cycles in both groups. Both effectiveness and cost-effectiveness of the strategies were evaluated from an intention-to-treat perspective. MAIN RESULTS AND THE ROLE OF CHANCE: We included 1515 women, of whom 483 (31.9%) entered the cohort, 511 (33.7%) RCT1 and 521 (34.4%) RCT2. Live births occurred in 420/747 (56.3%) women in the individualized strategy and 447/769 (58.2%) women in the standard strategy (risk difference -0.019 (95% CI, -0.06 to 0.02), P = 0.39; a total of 1516 women due to rounding up the half integer numbers). The individualized strategy was more expensive (delta costs/woman = €275 (95% CI, 40 to 499)). Individualized dosing reduced the occurrence of mild and moderate ovarian hyperstimulation syndrome (OHSS) and subsequently the costs for management of these OHSS categories (costs saved/woman were €35). The analysis based on AMH as a tool for dose individualization suggested comparable results. LIMITATIONS, REASONS FOR CAUTION: Despite a training programme, the AFC might have suffered from inter-observer variation. In addition, although strict cancel criteria were provided, selective cancelling in the individualized dose group (for poor response in particular) cannot be excluded as observers were not blinded for the FSH dose and small dose adjustments were allowed in subsequent cycles. However, as both first cycle live birth rates and cumulative live birth rates show no difference between strategies, the open design probably did not mask a potential benefit for the individualized group. Despite increasing consensus on using GnRH antagonist co-treatment in women predicted for a hyper response in particular, GnRH agonists were used in almost 80% of the women in this study. Hence, in those women, the AFC and bloodsampling for the post-hoc AMH analysis were performed during pituitary suppression. As the correlation between AFC and ovarian response is not compromised during GnRH agonist use, this will probably not have influenced classification of response. WIDER IMPLICATIONS OF THE FINDINGS: Individualized FSH dosing for the IVF/ICSI population as a whole should not be pursued as it does not improve live birth rates and it increases costs. Women scheduled for IVF/ICSI with a regular menstrual cycle are therefore recommended a standard FSH starting dose of 150 IU per day. Still, safety management by individualized dosing in predicted hyper responders is open for further research. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by The Netherlands Organisation for Health Research and Development (ZonMW number 171102020). AMH measurements were performed free of charge by Roche Diagnostics. TCT, HLT and SCO received an unrestricted personal grant from Merck BV. AH declares that the department of Obstetrics and Gynecology, University Medical Centre Groningen receives an unrestricted research grant from Ferring pharmaceutics BV, The Netherlands. CBL receives grants from Merck, Ferring and Guerbet. BWJM is supported by a NHMRC Practitioner Fellowship (GNT1082548) and reports consultancy for OvsEva, Merck and Guerbet. FJMB receives monetary compensation as a member of the external advisory board for Ferring pharmaceutics BV (the Netherlands) and Merck Serono (the Netherlands) for consultancy work for Gedeon Richter (Belgium) and Roche Diagnostics on automated AMH assay development (Switzerland) and for a research cooperation with Ansh Labs (USA). All other autors have nothing to declare. TRIAL REGISTRATION NUMBER: Registered at the ICMJE-recognized Dutch Trial Registry (www.trialregister.nl). Registration number: NTR2657.


Assuntos
Fertilização in vitro/métodos , Hormônio Foliculoestimulante/administração & dosagem , Reserva Ovariana , Injeções de Esperma Intracitoplásmicas/métodos , Adulto , Hormônio Antimülleriano/metabolismo , Coeficiente de Natalidade , Análise Custo-Benefício , Feminino , Fertilização in vitro/economia , Custos de Cuidados de Saúde , Humanos , Folículo Ovariano/patologia , Síndrome de Hiperestimulação Ovariana , Ovário/fisiologia , Indução da Ovulação/métodos , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Estudos Prospectivos , Injeções de Esperma Intracitoplásmicas/economia , Fatores de Tempo , Resultado do Tratamento
12.
Hum Reprod ; 30(10): 2364-75, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26311148

RESUMO

STUDY QUESTION: To what extent does oral contraception (OC) impair ovarian reserve parameters in women who seek fertility assessment and counselling to get advice on whether their remaining reproductive lifespan is reduced? SUMMARY ANSWER: Ovarian reserve parameters defined by anti-Müllerian hormone (AMH), antral follicle count (AFC) and ovarian volume were found to be significantly decreased by 19% (95% CI 9.1-29.3%), 18% (95% CI 11.2-24.8%) and 50% (95% CI 45.1-53.7%) among OC users compared with non-users. WHAT IS KNOWN ALREADY: AMH and AFC have proved to be reliable predictors of ovarian ageing. In women, AMH declines with age and data suggest a relationship with remaining reproductive lifespan and age at menopause. OC may alter parameters related to ovarian reserve assessment but the extent of the reduction is uncertain. STUDY DESIGN, SIZE, DURATION: A cross-sectional study of 887 women aged 19-46 attending the Fertility Assessment and Counselling Clinic (FACC) from 2011 to 2014 comparing ovarian reserve parameters in OC users with non-OC users. PARTICIPANTS/MATERIALS, SETTING, METHODS: The FAC Clinic was initiated to provide individual fertility assessment and counselling. All women were examined on a random cycle day by a fertility specialist. Consultation included; transvaginal ultrasound (AFC, ovarian volume, pathology), a full reproductive history and AMH measurement. Women were grouped into non-users and users of OC (all combinations of estrogen-progestin products and the contraceptive vaginal ring). Non-users included women with an intrauterine device (IUD) or no hormonal contraception. MAIN RESULTS AND THE ROLE OF CHANCE: Of the 887 women, 244 (27.5%) used OC. In a linear regression analyses adjusted for age, ovarian volume was 50% lower (95% CI 45.1-53.7%), AMH was 19% lower (95% CI 9.1-29.3%), and AFC was 18% lower (95% CI 11.2-24.8%) in OC users compared with non-users. Comparison of AMH at values of <10 pmol/l OC was found to have a significant negative influence on AMH (OR 1.6, 95% CI 1.1; 2.4, P = 0.03). Furthermore, we found a significant decrease in antral follicles sized 5-7 mm (P < 0.001) and antral follicles sized 8-10 mm (P < 0.001) but an increase in antral follicles sized 2-4 mm (P = 0.008) among OC users. The two groups (OC users versus non-users) were comparable regarding age, BMI, smoking and maternal age at menopause. LIMITATIONS, REASON FOR CAUTION: The study population comprised women attending the FAC Clinic. Recruitment was based on self-referral, which could imply a potential selection bias. Ovarian reserve was examined at a random cycle day. However, both AMH and AFC can be assessed independently of the menstrual cycle. The accuracy in predicting residual reproductive lifespan is still needed in both users and non-users of OC. WIDER IMPLICATIONS OF THE FINDINGS: OC has a major impact on the ovarian volume, and a moderate impact on AFC and AMH with a shift towards the smaller sized antral follicle subclasses. The most evident reduction occurs in the antral follicles of 5-7 and 8-10 mm with the highest number of AMH secreting granulosa cells. It is essential to be aware of the impact of OC use on ovarian reserve parameters when guiding OC users on their fertility status and reproductive lifespan. STUDY FUNDING/COMPETING INTERESTS: The FAC Clinic was established in 2011 as part of the ReproHigh collaboration. This study received funding through the Capital Region Research Fund and by EU-regional funding. There are no competing interests. TRIAL REGISTRATION NUMBER: The biobank connected to FAC Clinic is approved by the Scientific Ethical Committee (H-1-2011-081).


Assuntos
Anticoncepcionais Orais/uso terapêutico , Fertilidade/efeitos dos fármacos , Folículo Ovariano/patologia , Reserva Ovariana/efeitos dos fármacos , Ovário/efeitos dos fármacos , Adulto , Envelhecimento , Hormônio Antimülleriano/metabolismo , Anticoncepção , Estudos Transversais , Feminino , Humanos , Modelos Lineares , Pessoa de Meia-Idade , Ovário/fisiologia , Estudos Prospectivos , Reprodução , Inquéritos e Questionários , Adulto Jovem
13.
J Assist Reprod Genet ; 32(2): 195-205, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25392074

RESUMO

PURPOSE: The aim of this study was the investigation of caspase-3/7 activity and apoptosis related gene expression after vitrification and xenotransplantation of human ovarian fragments. METHODS: Ovarian specimens were obtained from normal female-to-male transsexual women during laparoscopic surgery and cut into small pieces and were considered as vitrified and non-vitrified groups. The morphological study, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, caspase-3/7 activity and apoptosis related gene expression analysis were done in both non-vitrified and vitrified groups in two steps (before transplantation of ovarian tissues and 30 days after transplantation). RESULT(S): In spite of high rate of normal follicles in both non-transplanted tissues these rates were significantly decreased in vitrified and non-vitrified grafted tissues, moreover grafted-vitrified tissue showed significantly less normal follicles than grafted-non-vitrified group (P < 0.05). The expression of some pro and anti-apoptotic genes in vitrified-warmed tissues were not changed compared to non-vitrified ones but the expression of Fas and caspase8 was increased and the expression of BRIC5 was decreased in this group (P < 0.05). In transplanted vitrified group the Bcl2, FasL and BRIC5 gene expression was high and caspase8 was low (P < 0.05). The expression of all genes in both grafted groups was more than non-grafted tissues except for caspase8 (P < 0.05). The TUNEL positive signals and caspase-3/7 activity were increased in both grafted groups compared to non-grafted groups and this enzyme activity in grafted-vitrified group was more than grafted-non-vitrified group (P < 0.05). CONCLUSION(S): This study provides the first evidence on the significant effect of vitrification on follicular apoptosis of grafted human ovarian tissue at mRNA level. The signs of follicular survival or degeneration detected by morphological assessment and caspase-3/7 activity were closely correlated to the changes in expression of apoptosis-related genes.


Assuntos
Apoptose/fisiologia , Ovário/fisiologia , Ovário/transplante , Vitrificação , Adulto , Apoptose/genética , Caspase 3/metabolismo , Caspase 7/metabolismo , Criopreservação , Feminino , Raios gama , Regulação da Expressão Gênica , Humanos , Marcação In Situ das Extremidades Cortadas , Ovário/patologia , Transplante Heterólogo
14.
Pest Manag Sci ; 71(6): 870-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25186022

RESUMO

BACKGROUND: The cotton bollworm Helicoverpa armigera has developed resistance to the insecticidal Cry1Ac toxins produced by Bacillus thuringiensis (Bt) in China. To gain a better understanding of the fitness cost associated with resistance evolution, reproductive capacities and ovarian development were examined in four strains of H. armigera: a Cry1Ac-susceptible strain (96S); a Cry1Ac-resistant strain fed on an artificial diet with Cry1Ac toxin for 135 generations (BtR); two strains derived from BtR: a strain grown without Cry1Ac selection for 38 generations (CK1) and a strain grown for one generation without Cry1Ac selection (CK2). RESULTS: Strains 96S and CK1 had similar reproductive capacity and Cry1Ac susceptibility. Compared with the 96S and CK1 strains, the fecundity and hatching rate of CK2 were respectively more than 30% and 50% lower. Moreover, the number of eggs laid by BtR was significantly lower than the number of eggs laid by 96S and CK1, but higher than the number of eggs laid by CK2. In accordance with the differences in reproductive capacity, ovarian development in CK2 and BtR was significantly delayed. CONCLUSION: These results indicated that there was a fitness cost in the reproductive physiology in the resistant strains. Reversion to susceptibility to the Bt Cry-toxin in the resistant CK1 strain was associated with an increase in reproductive capacity.


Assuntos
Bacillus thuringiensis , Proteínas de Bactérias/metabolismo , Endotoxinas/metabolismo , Aptidão Genética , Proteínas Hemolisinas/metabolismo , Mariposas/fisiologia , Controle Biológico de Vetores , Animais , Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis , Feminino , Mariposas/genética , Ovário/fisiologia , Reprodução , Especificidade da Espécie
15.
Theriogenology ; 82(7): 997-1006, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25132101

RESUMO

To date, there is no information on gonadal steroidogenic activity of female goral (Naemorhedus griseus), a threatened species of Thailand. Captive goral populations have been established to produce animals for ex situ conservation and reintroduction, but as yet none are self-sustaining. The objectives of the present study were to (1) determine the influence of season on ovarian steriodogenic function; and (2) examine the relationship between gonadal hormone excretion and sexual behaviors throughout the year. Fecal samples were collected 5 to 7 days/wk for 15 months from 8 adult females housed at Omkoi Wildlife Breeding Center in Thailand and analyzed for ovarian steroid metabolites using validated enzyme immunoassays. Observations of sexual behaviors and mating were conducted each morning for 30 min/session. Based on fecal estrogen and progestagen metabolite concentrations, the overall estrous cycle length was about 21 days, with a 2- to 3-day follicular phase and an 18- to 20-day luteal phase. Sexual behaviors, most notably tail-up, increased for 2 to 3 days during the time estrogens were elevated during mating. Fecal progestagens were elevated during luteal phases and increased further during gestation, which lasted approximately 7 months. The lactation period was 5 months, and females were anestrus for 2 to 5 of those months, with the exception of one that cycled continuously throughout. Two females conceived around 2 months postpartum and so were pregnant during lactation. Birth records over the past 21 years indicated young are born throughout the year. This combined with the hormonal data suggests that female gorals are not strongly seasonal, at least in captivity, although there was considerable variation among females in estrogen and progestagen patterns. In conclusion, fecal steroid metabolite monitoring is an effective means of assessing ovarian function in this species and will be a useful tool for breeding management and planned development of assisted reproductive techniques such as artificial insemination and embryo transfer.


Assuntos
Artiodáctilos/fisiologia , Fezes/química , Ovário/fisiologia , Esteroides/química , Animais , Feminino , Masculino , Estações do Ano , Comportamento Sexual Animal/fisiologia , Esteroides/metabolismo , Fatores de Tempo
16.
J Pediatr Surg ; 49(7): 1177-80, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24952812

RESUMO

PURPOSE: We developed a new technique of temporary ovarian transposition (OT) for prepubertal girls undergoing brachytherapy. The aim of this study was to describe it, assess its feasibility and safety and calculate the dose delivered to the ovary in order to prove its efficacy. METHODS: Sixteen prepubertal patients underwent temporary OT for brachytherapy at our center from March 2001 to December 2012. OT was done either by laparotomy or by laparoscopy. In all patients, the ovaries were grasped with an atraumatic forceps and mobilized above the iliac crest level as high as possible without any dissection or division of the ovarian ligaments or of the fallopian tube. They were sutured to the anterior abdominal wall by a transfixing stitch of non-dissolvable suture knotted on the outside of the patient on a pledget. RESULTS: Median age at surgery was 3 years (range: 2-9 years). The integrity of the fallopian tube was respected and not a single ligament was dissected or divided. None of the patients had intraoperative or postoperative complications. The stitches were retrieved after completion of irradiation and the ovaries in all the patients fell back into the pelvis. The calculated median radiation dose to the ovary was 1.4 Gy (range: 0.4-2.4 Gy). CONCLUSIONS: This surgical technique is simple and safe, either by laparotomy or by laparoscopy. It meets the radiation and physical constraints in prepubertal girls with vaginal or bladder RMS. However, longer follow-up is required to assess the ovarian function.


Assuntos
Braquiterapia , Ovário/efeitos da radiação , Ovário/cirurgia , Neoplasias da Bexiga Urinária/radioterapia , Neoplasias do Colo do Útero/radioterapia , Neoplasias Vaginais/radioterapia , Adenocarcinoma de Células Claras/radioterapia , Criança , Pré-Escolar , Estudos de Viabilidade , Feminino , Humanos , Laparoscopia , Laparotomia , Ovário/fisiologia , Dosagem Radioterapêutica , Rabdomiossarcoma/radioterapia
17.
PLoS One ; 9(6): e98233, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24911973

RESUMO

Despite attention focused on the population status and rebuilding trajectory of Atlantic bluefin tuna (Thunnus thynnus), the reproduction and spawning biology remains poorly understood, especially in the NW Atlantic. At present, the eastern and western spawning populations are believed to exhibit different reproductive characteristics and, consequently, stock productivity. However, our study suggests that the two spawning populations, the Gulf of Mexico and the Mediterranean Sea, could show similar reproductive features and spawning strategies. Between 2007 and 2009, gonad samples from female Atlantic bluefin tuna were collected in the northern Gulf of Mexico (n = 147) and in the western Mediterranean Sea (n = 40). The histological and stereological analysis confirmed that sampled eastern and western bluefin tuna exhibit the same spawning duration (three months) but the spawning in the Gulf of Mexico begins one month earlier than in the Mediterranean Sea. Western bluefin tuna caught in the peak of the spawning season (May) showed a similar spawning frequency (60%) to the spawning peak observed in the Mediterranean Sea (June). Fecundity for the Gulf of Mexico fish (28.14 eggs · g(-1)) was lower but not significantly different than for fish sampled in the Mediterranean Sea (45.56 eggs · g(-1)). Our study represents the first comparative histological analysis of the eastern and western spawning stocks whose findings, combined with new determinations of size/age at maturity and possible alternative spawning areas, might suggest basic life history attributes warrant further scientific and management attention.


Assuntos
Reprodução , Atum/fisiologia , Animais , Feminino , Golfo do México , Mar Mediterrâneo , Ovário/citologia , Ovário/fisiologia
18.
PLoS One ; 9(3): e91073, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24614306

RESUMO

OBJECTIVE: To evaluate and compare the distribution and density of primordial follicles within a whole sheep ovary and to gain insight into how to overcome the impact of natural follicular heterogeneity on the experimental results. DESIGN: Histological study. SETTING: Academic research center. ANIMALS: Five- to nine-month-old ewes. INTERVENTIONS: Freshly sampled whole sheep ovaries were collected and prepared for histological analysis. MAIN OUTCOME MEASURE(S): The follicular densities and distributions were determined for hematoxylin and eosin sections. A mathematical model was derived based on the follicle counts and Monte-Carlo simulations. RESULTS: Heterogeneous distributions and densities of primordial follicles were identified 1) for distinct areas of the same ovarian cortex, 2) between the ovaries of the same animal and 3) across different ewes. A mathematical model based on the analysis of 37,153 primordial follicles from 8 different ovaries facilitated the estimation of the number of cortical biopsies and sections that had to be analyzed to overcome such heterogeneity. CONCLUSION: The influence of physiological follicular heterogeneity on experimental and clinical results can be overcome when a definite number of cortical pieces and sections are taken into consideration.


Assuntos
Modelos Animais , Ovário/fisiologia , Medicina Reprodutiva/métodos , Ovinos/fisiologia , Animais , Simulação por Computador , Feminino , Modelos Biológicos , Método de Monte Carlo , Folículo Ovariano/fisiologia , Tamanho da Amostra
19.
Semin Reprod Med ; 31(5): 380-6, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23934699

RESUMO

More than 4 million menopausal women are from ethnic minority groups. Over the past 25 years, recognition of the importance of social, emotional, and physical changes of midlife to women's long-term health and well-being has emerged. Multiple factors influence how a woman perceives menopausal changes and what she addresses as associated symptoms. Factors such as educational level to socioeconomic status, health-related factors, stress, and marital status influence these choices. Increasingly, researchers are reporting on the impact of race and ethnicity on menopausal symptoms. Understanding similarities and differences among women's perceptions, attitudes, and expectations surrounding menopause improves delivery of culturally appropriate care and promotes lifestyles that may decrease symptoms and increase quality of life. Historically, the majority of the research in this area has been conducted in Western countries with clinical samples of women predominantly from European backgrounds. Thus, this population has shaped the emerging clinical picture of the midlife menopausal transition. Recently, studies of non-European women, both in the United States and internationally, indicate significant variations in their experiences during this transition, but these cultural differences have not broadened the understanding of the meaning of this universal experience. To date, there are still large knowledge gaps in race, ethnic, and cultural differences in menopausal health. The content of this review summarizes the current body of knowledge on racial differences in the menopause experience.


Assuntos
Disparidades nos Níveis de Saúde , Menopausa , Saúde das Minorias , Negro ou Afro-Americano , Asiático , Feminino , Hispânico ou Latino , Terapia de Reposição Hormonal , Humanos , Sistema Hipotálamo-Hipofisário/crescimento & desenvolvimento , Sistema Hipotálamo-Hipofisário/fisiologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Menopausa/etnologia , Menopausa/fisiologia , Pessoa de Meia-Idade , Saúde das Minorias/etnologia , Obesidade/etnologia , Obesidade/genética , Obesidade/fisiopatologia , Obesidade/terapia , Ovário/crescimento & desenvolvimento , Ovário/fisiologia , Ovário/fisiopatologia , Estados Unidos
20.
J Evol Biol ; 26(7): 1406-16, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23675858

RESUMO

Melanism is an important component of insect cuticle and serves numerous functions that enhance fitness. Despite its importance, there is little information on its genetic basis or its phenotypic and genetic correlation with fitness-related traits. Here, we examine the heritability of melanism in the wing dimorphic sand cricket and determine its phenotypic and genetic correlation with wing morphology, gonad mass and size of the dorso-longitudinal muscles (the principle flight muscles). Previously demonstrated trade-offs among these traits are significant factors in the evolution of life history variation. Using path analysis, we show that melanization is causally related to gonad mass, but not flight muscle mass. Averaged over the sexes, the heritability of melanism was 0.61, the genetic correlation with gonad mass was -0.36 and with wing morph was 0.51. The path model correctly predicted the ranking of melanization score in lines selected for increased ovary mass, increased flight muscle mass, an index that increased both traits and an unselected control. Our results support the general hypothesis that melanization is costly for insects and negatively impacts investment in early reproduction.


Assuntos
Aptidão Genética , Gryllidae/fisiologia , Animais , Evolução Biológica , Feminino , Gryllidae/genética , Masculino , Melaninas/genética , Músculo Esquelético/fisiologia , Tamanho do Órgão , Ovário/fisiologia , Fenótipo , Densidade Demográfica , Reprodução/genética , Testículo/fisiologia , Asas de Animais/fisiologia
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