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1.
Animal ; 15(3): 100141, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33573941

RESUMO

Boar taint is an unpleasant taste and odor that can occur in entire male pigs and is caused by androstenone, skatole, and to a lesser extent indole accumulating in fat tissue. In the present observational study, we evaluated an extensive list of such potential risk factors which influence boar taint: social hierarchy and puberty attainment, housing, health, preslaughter conditions, season, feed, carcass composition, slaughter weight or age, and breed. Details on these factors were collected by interviews with the participating farmers, observations on each farm by trained observers and farmers, as well as slaughterhouse data. Twenty-two farms (in West- and East-Flanders, ranging from 160 to 600 sows, selected on suitability) raising entire male pigs were included in the study to evaluate the link between boar taint and potential risk factors related to the farm and slaughter batch (114 slaughter batches and 16 791 entire male pigs in total). Average olfactory boar taint prevalence was 1.8 ±â€¯0.8%. Boar taint prevalence varied also within farms up to a maximum range between slaughter batches of 9.1% which suggests an effect of factors varying between slaughter batches such as season or other variables varying between slaughter batches. Less aggressive behavior at the end of fattening as well as lower skin lesion scores at fattening as well as at slaughter could be associated with less boar taint. The same might be said for sexual behavior, though less convincingly from this study. Measures that reduce aggression and stress have therefore have the potential to lower boar taint prevalence. The same might be said for sexual behavior, though less convincingly from this study. Furthermore, boar taint prevalence was generally higher in winter than in summer, which is relevant from a planning perspective for the slaughterhouses to seek alternative markets. Finally, increased CP gave significantly lower boar taint prevalences. This may to some extent be explained by the negative association between boar taint and lean meat percentage, as increased dietary CP levels promote the carcass lean meat percentages which can then be associated with lower boar taint levels.


Assuntos
Maturidade Sexual , Escatol , Animais , Fazendas , Feminino , Masculino , Carne/análise , Prevalência , Fatores de Risco , Suínos
2.
Nat Commun ; 12(1): 1064, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33594056

RESUMO

Polycystic ovary syndrome (PCOS) is characterized by an oligo-anovulation, hyperandrogenism and polycystic ovarian morphology combined with major metabolic disturbances. However, despite the high prevalence and the human and economic consequences of this syndrome, its etiology remains unknown. In this study, we show that female Goto-Kakizaki (GK) rats, a type 2 diabetes mellitus model, encapsulate naturally all the reproductive and metabolic hallmarks of lean women with PCOS at puberty and in adulthood. The analysis of their gestation and of their fetuses demonstrates that this PCOS-like phenotype is developmentally programmed. GK rats also develop features of ovarian hyperstimulation syndrome. Lastly, a comparison between GK rats and a cohort of women with PCOS reveals a similar reproductive signature. Thus, this spontaneous rodent model of PCOS represents an original tool for the identification of the mechanisms involved in its pathogenesis and for the development of novel strategies for its treatment.


Assuntos
Síndrome do Ovário Policístico/patologia , Adiposidade , Animais , Animais Recém-Nascidos , Peso Corporal , Análise Discriminante , Modelos Animais de Doenças , Dislipidemias/patologia , Sistema Endócrino/patologia , Ciclo Estral , Feminino , Teste de Tolerância a Glucose , Gonadotropinas/farmacologia , Hormônios/sangue , Humanos , Secreção de Insulina , Análise dos Mínimos Quadrados , Lipídeos/química , Masculino , Troca Materno-Fetal , Análise Multivariada , Ovário/patologia , Ovário/fisiopatologia , Fenótipo , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/fisiopatologia , Gravidez , Ratos Wistar , Reprodução , Maturidade Sexual
3.
Toxicol Lett ; 342: 6-19, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33581290

RESUMO

2,2',4,4'-Tetrabromodiphenyl ether (BDE47), a flame retardant, is extensively distributed in the food chain. However, whether BDE47 affects Leydig cell development during prepuberty remains unclear. BDE47 was daily gavaged to 21-day-old Sprague-Dawley male rats with 0 (corn oil), 0.1, 0.2, and 0.4 mg/kg for 14 days. BDE47 did not affect the body weight or testis weight of rats. It significantly increased serum testosterone level at 0.4 mg/kg, but decreased luteinizing hormone (LH) level without affecting estradiol level. BDE47 induced Leydig cell hyperplasia (the number of CYP11A1-positive Leydig cells increased), and up-regulated the expression of Scarb1, Star, Hsd11b1, Pcna, and Ccnd1 in the testis. BDE47 significantly reduced p53 and p21 levels but increased CCND1 level. It also markedly increased the phosphorylation of AKT1, AKT2, ERK1/2, and CREB. BDE47 significantly up-regulated the expression of Scarb1, Star, and Hsd11b1 and stimulated androgen production by immature Leydig cells from rats under basal, LH, and 8Br-cAMP stimulated conditions at 100 nM in vitro. In conclusion, BDE47 increased Leydig cell number and up-regulated the expression of Scarb1 and Star, thereby leading to increased testosterone synthesis.


Assuntos
Éteres Difenil Halogenados/toxicidade , Células Intersticiais do Testículo/fisiologia , Maturidade Sexual/fisiologia , Células-Tronco/efeitos dos fármacos , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Animais , Células Cultivadas , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Relação Dose-Resposta a Droga , Hormônio Foliculoestimulante , Regulação da Expressão Gênica/efeitos dos fármacos , Éteres Difenil Halogenados/administração & dosagem , Éteres Difenil Halogenados/química , Hormônio Luteinizante , Masculino , Estrutura Molecular , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo
4.
Animal ; 15(2): 100095, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33573980

RESUMO

Optimal management of gilt reproduction requires oestrus synchronization. Hormonal treatments are used for this purpose, but there is a growing demand for non-hormonal alternatives, especially in organic farms. The boar effect is an important alternative opportunity to induce and synchronize oestrus without hormones. Before puberty, gilts exhibit a 'waiting period' during which boar exposure could induce and synchronize the first ovulation. We searched for salivary biomarkers of this period of boar effect receptivity to improve detection of the gilts to stimulate with the perspective of enhancing the efficacy of the boar effect. Saliva samples were collected from 30 Large-White×Landrace crossbred gilts between 140 and 175 days of age. Gilts were exposed twice a day to a boar and subjected to oestrus detection from 150 to 175 days of age. Among the 30 gilts, 10 were detected in oestrus 4 to 7 days after the first introduction of the boar and were considered receptive to the boar effect, 14 were detected in oestrus more than 8 days after first boar contact, and six did not show oestrus and were considered non-receptive. Saliva samples from six receptive and six non-receptive gilts were analyzed for steroidome and for metabolome using gas chromatography coupled to tandem mass spectrometry and 1H nuclear magnetic resonance spectroscopy, respectively. Four saliva samples per gilt were analyzed: 25 days and 11 days before boar introduction, the day of boar introduction, 3 days later for receptive gilts or 7 days later for non-receptive gilts. Twenty-nine steroids and 31 metabolites were detected in gilt saliva. Salivary concentrations of six steroids and three metabolites were significantly different between receptive and non-receptive gilts: progesterone and glycolate 25 days before boar introduction, 3α5ß20α- and 3ß5α20ß-hexahydroprogesterone, dehydroepiandrosterone, androstenediol, succinate, and butyrate 11 days before boar introduction, and 3ß5α-tetrahydroprogesterone on the day of boar introduction. Thus, nine potential salivary biomarkers of boar effect receptivity were identified in our experimental conditions. Further studies with higher numbers of gilts and salivary sampling points are necessary to ascertain their reliability.


Assuntos
Saliva , Maturidade Sexual , Animais , Biomarcadores , Feminino , Cromatografia Gasosa-Espectrometria de Massas/veterinária , Masculino , Metaboloma , Reprodutibilidade dos Testes , Suínos
5.
Environ Sci Pollut Res Int ; 28(14): 17343-17354, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33398759

RESUMO

An accurate assessment of the environmental risk of soils contaminated by metal(loid)s (MEs) requires quantifying exposure and knowing the toxicity of contaminants transferred to biota. For this purpose, two indices have been developed with the bioindicator Cantareus aspersus to assess exposure (SET: sum of the excess of transfer) and risk (ERITME: evaluation of the risk of the transferred metal elements) of multi-contaminated soils. If the SET and ERITME indices allow characterization of exposure and risk based on unspecific toxicity points, then the link between these indices and real effects on some toxicological endpoints, such as growth or sexual maturation, remains to be demonstrated. For this purpose, sub-adult snails were exposed for 28 days to 38 ME-contaminated soils. Relationships between the SET and/or ERITME indices and health alterations in C. aspersus were determined using Spearman correlations, linear regressions, univariate regression trees, and kinetic models. Relationships were determined between the values of the SET and ERITME indices, bioaccumulation as an indicator of ME bioavailability, and the alteration in physiological endpoints, such as the shell development used as a non-invasive indicator of sexual maturation. The results enabled the determination of three levels of risk according to the differences in reaching sexual maturity: no risk, uncertain, and proven risk depended on whether the value of ERITME was below, in, or beyond the interval [2574-22720], respectively. This study provides the first benchmarks with the SET and ERITME indices to interpret the risk of contaminated soils to snails and to relate the environmental and toxicological bioavailability of ME mixtures.


Assuntos
Poluentes do Solo , Animais , Disponibilidade Biológica , Medição de Risco , Maturidade Sexual , Caramujos , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
6.
Neurosci Lett ; 746: 135657, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33482312

RESUMO

During puberty, sexual hormones induce crucial changes in neural circuit organization, leading to significant sexual dimorphism in adult behaviours. The ventrolateral division of the ventromedial nucleus of the hypothalamus (VMHvl) is the major neural site controlling the receptive component of female sexual behaviour, which is dependent on ovarian hormones. The inputs to the VMHvl, originating from the medial nucleus of the amygdala (MeA), transmit essential information to trigger such behaviour. In this study, we investigated the projection pattern of the MeA to the VMHvl in ovariectomized rats at early puberty. Six-week-old Sprague-Dawley rats were ovariectomized (OVX) and, upon reaching 90 days of age, were subjected to iontophoretic injections of the neuronal anterograde tracer Phaseolus vulgaris leucoagglutinin into the MeA. Projections from the MeA to the VMHvl and to other structures included in the neural circuit responsible for female sexual behaviour were analysed in the Control and OVX groups. The results of the semi-quantitative analysis showed that peripubertal ovariectomy reduced the density of intra-amygdalar fibres. The stereological estimates, however, failed to find changes in the organization of the terminal fields of nerve fibres from the MeA to the VMHvl in the adult. The present data show that ovariectomized rats during the peripubertal phase did not undergo significant changes in MeA fibres reaching the VMHvl; however, they suggest a possible effect of ovariectomy on MeA connectivity under amygdalar subnuclei.


Assuntos
Complexo Nuclear Corticomedial/metabolismo , Rede Nervosa/metabolismo , Ovariectomia/tendências , Maturidade Sexual/fisiologia , Núcleo Hipotalâmico Ventromedial/metabolismo , Fatores Etários , Animais , Complexo Nuclear Corticomedial/diagnóstico por imagem , Feminino , Imageamento Tridimensional/tendências , Rede Nervosa/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem , Vias Neurais/metabolismo , Ovariectomia/efeitos adversos , Ratos , Ratos Sprague-Dawley , Núcleo Hipotalâmico Ventromedial/diagnóstico por imagem
7.
J Dairy Sci ; 104(5): 5794-5804, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33516553

RESUMO

Fertility is of primary economic importance in dairy cattle and the most common reason for involuntary culling. However, standard fertility traits have very low heritability that renders genetic selection slow and difficult. In this study, we explored fertility from an endocrine standpoint. A total of 1,163 crossbred Holstein-Normande females in a 3-generation familial design were studied for progesterone level measured every 10 d to determine age at puberty (PUB) and commencement of postpartum luteal activity (CPLA). Genetic parameters were estimated using REML with WOMBAT software. The heritability estimates were 0.38 ± 0.10 and 0.16 ± 0.07 for PUB and CPLA, respectively. Moreover, the 2 traits were genetically correlated (0.45 ± 0.23), suggesting a partially common determinism. Because of the family structure, a linkage disequilibrium and linkage analysis approach was preferred over standard genome-wide association study to map genomic regions associated with these traits. Ten quantitative trait loci (QTL) were detected for PUB on chromosomes 1, 3, 11, 13, 14, 21, and 29, whereas 3 QTL were associated with CPLA on chromosomes 21 and 26. Only the QTL on chromosome 21 was common to both traits. Four functional candidate genes (NCOA2, GAS2, OVOL1, and FOSL1) were identified in the detected regions. These findings will contribute to a clearer understanding of fertility determinism and enhance the value of introducing endocrinological data in fertility studies.


Assuntos
Estudo de Associação Genômica Ampla , Progesterona , Animais , Bovinos/genética , Feminino , Fertilidade/genética , Estudo de Associação Genômica Ampla/veterinária , Periodicidade , Maturidade Sexual/genética
8.
J Dairy Sci ; 104(3): 3707-3721, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33455798

RESUMO

This study investigated the hypothesis that dairy heifers divergent in genetic merit for fertility traits differ in the age of puberty and reproductive performance. New Zealand's fertility breeding value (FertBV) is the proportion of a sire's daughters expected to calve in the first 42 d of the seasonal calving period. We used the New Zealand national dairy database to identify and select Holstein-Friesian dams with either positive (POS, +5 FertBV, n = 1,334) or negative FertBV (NEG, -5% FertBV, n = 1,662) for insemination with semen from POS or NEG FertBV sires, respectively. The resulting POS and NEG heifers were predicted to have a difference in average FertBV of 10 percentage points. We enrolled 640 heifer calves (POS, n = 324; NEG, n = 316) at 9 d ± 5.4 d (± standard deviation; SD) for the POS calves and 8 d ± 4.4 d old for the NEG calves. Of these, 275 POS and 248 NEG heifers were DNA parent verified and retained for further study. The average FertBV was +5.0% (SD = 0.74) and -5.1% (SD = 1.36) for POS and NEG groups, respectively. Heifers were reared at 2 successive facilities as follows: (1) calf rearing (enrollment to ∼13 wk of age) and (2) grazier, after 13 wk until 22 mo of age. All heifers wore a collar with an activity sensor to monitor estrus events starting at 8 mo of age, and we collected weekly blood samples when individual heifers reached 190 kg of body weight (BW) to measure plasma progesterone concentrations. Puberty was characterized by plasma progesterone concentrations >1 ng/mL in at least 2 of 3 successive weeks. Date of puberty was defined when the first of these samples was >1 ng/mL. Heifers were seasonally bred for 98 d starting at ∼14 mo of age. Transrectal ultrasound was used to confirm pregnancy and combined with activity data to estimate breeding and pregnancy dates. We measured BW every 2 wk, and body condition and stature at 6, 9, 12, and 15 mo of age. The significant FertBV by day interaction for BW was such that the NEG heifers had increasingly greater BW with age. This difference was mirrored with the significant FertBV by month interaction for average daily gain, with the NEG heifers having a greater average daily gain between 9 and 18 mo of age. There was no difference in heifer stature between the POS and NEG heifers. The POS heifers were younger and lighter at puberty, and were at a lesser mature BW, compared with the NEG heifers. As a result, 94 ± 1.6% of the POS and 82 ± 3.2% of the NEG heifers had reached puberty at the start of breeding. The POS heifers were 20% and 11% more likely to be pregnant after 21 d and 42 d of breeding than NEG heifers (relative risk = 1.20, 95% confidence interval of 1.03-1.34; relative risk = 1.11, 95% confidence interval of 1.01-1.16). Results from this experiment support an association between extremes in genetic merit for fertility base on cow traits and heifer reproduction. Our results indicate that heifer puberty and pregnancy rates are affected by genetic merit for fertility traits, and these may be useful phenotypes for genetic selection.


Assuntos
Fertilidade , Maturidade Sexual , Animais , Bovinos/genética , Feminino , Fertilidade/genética , Nova Zelândia , Fenótipo , Gravidez , Taxa de Gravidez , Reprodução , Maturidade Sexual/genética
9.
J Zoo Wildl Med ; 51(4): 848-855, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33480565

RESUMO

Evaluation of sex ratios is a critical component of chelonian captive breeding programs and may become increasingly useful to assess the demographics of free-living populations. In many reptile species, the sex of immature animals cannot be determined based on external features. Endoscopic sex identification is an accurate and safe method to identify the sex of immature individuals of some chelonian species. A number of studies describe this technique in controlled, hospital settings and report significant interspecies variations in gonad morphology; however, there are few reports describing this technique in field conditions. In the current study, the gonadal morphology of 40 immature Western Santa Cruz tortoises (Chelonoidis porteri) on Santa Cruz Island in Galapagos, Ecuador, was assessed. A previously described endoscopic protocol was used to perform sex identification under field conditions. Tortoises were anesthetized using an intramuscular injection of ketamine (10 mg/kg) and medetomidine (0.1 mg/kg), which provided an adequate plane of anesthesia. The medetomidine was reversed with atipamezole (0.5 mg/kg). Field conditions presented challenges such as limited control over lighting, suboptimal patient positioning, and restricted power supply for endoscopy equipment. The immature testicle in Western Santa Cruz tortoises was oval, reddish pink, and tightly adhered to the coelomic membrane ventral to the kidney. The surface of the gonads resembled other species with the notable exception that the ovaries lacked a significant number of primordial follicles. These gonadal characteristics were consistent, with only one individual identified as undetermined sex of the 40 samples. This field-based endoscopic gonadal evaluation was a safe and sensitive technique for determining the sex of free-living immature Western Santa Cruz Galapagos tortoises.


Assuntos
Anestesia/veterinária , Ovário/anatomia & histologia , Maturidade Sexual , Testículo/anatomia & histologia , Analgésicos/administração & dosagem , Analgésicos/farmacologia , Animais , Feminino , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/farmacologia , Ketamina/administração & dosagem , Ketamina/farmacologia , Masculino , Medetomidina/administração & dosagem , Medetomidina/farmacologia , Ovário/crescimento & desenvolvimento , Testículo/crescimento & desenvolvimento , Tartarugas/fisiologia
10.
Am Nat ; 197(1): 29-46, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33417522

RESUMO

AbstractDetecting contemporary evolution requires demonstrating that genetic change has occurred. Mixed effects models allow estimation of quantitative genetic parameters and are widely used to study evolution in wild populations. However, predictions of evolution based on these parameters frequently fail to match observations. Here, we applied three commonly used quantitative genetic approaches to predict the evolution of size at maturity in a wild population of Trinidadian guppies. Crucially, we tested our predictions against evolutionary change observed in common-garden experiments performed on samples from the same population. We show that standard quantitative genetic models underestimated or failed to detect the cryptic evolution of this trait as demonstrated by the common-garden experiments. The models failed because (1) size at maturity and fitness both decreased with increases in population density, (2) offspring experienced higher population densities than their parents, and (3) selection on size was strongest at high densities. When we accounted for environmental change, predictions better matched observations in the common-garden experiments, although substantial uncertainty remained. Our results demonstrate that predictions of evolution are unreliable if environmental change is not appropriately captured in models.


Assuntos
Evolução Biológica , Tamanho Corporal/genética , Poecilia/genética , Animais , Aptidão Genética , Masculino , Modelos Genéticos , Poecilia/anatomia & histologia , Densidade Demográfica , Seleção Genética , Maturidade Sexual
11.
Am J Physiol Endocrinol Metab ; 320(3): E415-E424, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33308013

RESUMO

Sex steroids are critical for skeletal development and maturation during puberty as well as for skeletal maintenance during adult life. However, the exact time during puberty when sex steroids have the highest impact as well as the ability of bone to recover from transient sex steroid deficiency is unclear. Surgical castration is a common technique to study sex steroid effects in rodents, but it is irreversible, invasive, and associated with metabolic and behavioral alterations. Here, we used a low dose (LD) or a high dose (HD) of gonadotropin-releasing hormone antagonist to either temporarily or persistently suppress sex steroid action in male mice, respectively. The LD group, a model for delayed puberty, did not show changes in linear growth or body composition, but displayed reduced trabecular bone volume during puberty, which fully caught up at adult age. In contrast, the HD group, representing complete pubertal suppression, showed a phenotype reminiscent of that observed in surgically castrated rodents. Indeed, HD animals exhibited severely impaired cortical and trabecular bone acquisition, decreased body weight and lean mass, and increased fat mass. In conclusion, we developed a rodent model of chemical castration that can be used as an alternative to surgical castration. Moreover, the transient nature of the intervention enables to study the effects of delayed puberty and reversibility of sex steroid deficiency.NEW & NOTEWORTHY We developed a rodent model of chemical castration, which can be used as an alternative to surgical castration. Moreover, the transient nature of the intervention enables to study the effects of delayed puberty and reversibility of sex steroid deficiency.


Assuntos
Desenvolvimento Ósseo , Osso e Ossos/fisiologia , Hormônios Esteroides Gonadais/deficiência , Hipogonadismo/patologia , Animais , Composição Corporal/efeitos dos fármacos , Desenvolvimento Ósseo/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Hormônios Esteroides Gonadais/farmacologia , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Hormônio Liberador de Gonadotropina/farmacologia , Antagonistas de Hormônios/farmacologia , Hipogonadismo/complicações , Hipogonadismo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Orquiectomia , Maturidade Sexual/fisiologia , Fatores de Tempo
12.
Environ Res ; 192: 110279, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33039529

RESUMO

Dioxin was historically one of the most common industrial contaminants with several major industry accidents, as well as governmental actions involving military service, having exposed large numbers of the worldwide population over the past century. Previous rat studies have demonstrated the ability of dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)) exposure to promote the epigenetic transgenerational inheritance of disease susceptibility in subsequent generations. The types of disease previously observed include puberty abnormalities, testis, ovary, kidney, prostate and obesity pathologies. The current study was designed to use an epigenome-wide association study (EWAS) to identify potential sperm DNA methylation biomarkers for specific transgenerational diseases. Therefore, the transgenerational F3 generation dioxin lineage male rats with and without a specific disease were compared to identify differential DNA methylation regions (DMRs) as biomarkers for disease. The genomic features of the disease-specific DMRs were characterized. Observations demonstrate that disease-specific epimutation DMRs exist for the transgenerational dioxin lineage rats that can potentially be used as epigenetic biomarkers for testis, kidney, prostate and obesity diseases. These disease-specific DMRs were associated with genes that have previously been shown to be linked with the specific diseases. This EWAS for transgenerational disease identified potential epigenetic biomarkers and provides the proof of concept of the potential to develop similar biomarkers for humans to diagnose disease susceptibilities and facilitate preventative medicine.


Assuntos
Dioxinas , Dibenzodioxinas Policloradas , Animais , Biomarcadores/metabolismo , Metilação de DNA , Dioxinas/toxicidade , Epigênese Genética , Masculino , Ratos , Ratos Sprague-Dawley , Maturidade Sexual , Espermatozoides/metabolismo
13.
PLoS One ; 15(10): e0238986, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33027263

RESUMO

The Greenland shark (Somniosus microcephalus, Squaliformes: Somniosidae) is a long-lived Arctic top predator, which in combination with the high historical and modern fishing pressures, has made it subject to increased scientific focus in recent years. Key aspects of reproduction are not well known as exemplified by sparse and contradictory information e.g. on birth size and number of pups per pregnancy. This study represents the first comprehensive work on Greenland shark reproductive biology based on data from 312 specimens collected over the past 60 years. We provide guidelines quantifying reproductive parameters to assess specific maturation stages, as well as calculate body length-at-maturity (TL50) which was 2.84±0.06 m for males and 4.19±0.04 m for females. From the available information on the ovarian fecundity of Greenland sharks as well as a meta-analysis of Squaliform reproductive parameters, we estimate up to 200-324 pups per pregnancy (depending on maternal size) with a body length-at-birth of 35-45 cm. These estimates remain to be verified by future observations from gravid Greenland sharks.


Assuntos
Tubarões/fisiologia , Animais , Animais Recém-Nascidos/anatomia & histologia , Regiões Árticas , Tamanho Corporal , Feminino , Fertilidade , Genitália/crescimento & desenvolvimento , Groenlândia , Masculino , Gravidez , Reprodução/fisiologia , Maturidade Sexual , Tubarões/anatomia & histologia , Tubarões/crescimento & desenvolvimento
14.
Georgian Med News ; (304-305): 135-141, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32965264

RESUMO

The purpose of this scientific work was to investigate the development of puberty in females-offspring born to mothers of different age with fetoplacental insufficiency (FPI) and to evaluate efficacy of base and combined drug therapy during pregnancy. Negative influence of FPI on the puberty genesis of females-offspring born to mothers of different reproductive age is considered to be the results of the investigation. In particular, the increased anogenital distance, which is the sign of estrogen deficiency, has been observed in females-offspring born to reproductively young mothers with FPI. Females-offspring born to reproductively matured mothers with FPI have demonstrated more negative changes of reproductive system development. That is, body mass and anogenital distance increasing amid accelerated sexual development have been detected. The increasing of testosterone level has caused inadequate ovaries stimulation which has led to steroid genesis disturbances. During histological investigation of ovarian structure of pubertal rats born to mothers of both groups of age, the decreasing of follicles density, the disturbance in follicles types ratio - early secondary follicles were prevailed, declining folliculogenesis reserve and increased number of atretical follicles have been observed. The introduction of pharmaceutical composition to pregnant rats of both groups of age amid fetoplacental insufficiency leads to stronger normalization of reproductive system development in females-offspring than using of drug of comparison.


Assuntos
Mães , Maturidade Sexual , Feminino , Humanos , Ovário , Parto , Gravidez , Reprodução
15.
Chemosphere ; 258: 127361, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947662

RESUMO

In female mammals, puberty and fertility are regulated by the synthesis of estradiol (E2) by the ovaries at the infantile stage and at the approach of puberty, a process which may be affected by endocrine disrupting chemicals (EDC)s acting through the Aryl hydrocarbon receptor (AhR). However, there is no information on AhR-mediated regulation of ovarian estrogenic activity during these developmental periods. Here, we assessed in mouse models, the intrinsic and exogenous ligand-induced AhR action on E2 synthesis at the infantile stage (14 days postnatal (dpn)) and at the approach of puberty (28 dpn). Intrinsic AhR pathway became activated in the ovary at the approach of puberty, as suggested by the decreased intra-ovarian expression in prototypical and steroidogenesis-related AhR targets and E2 contents in Ahr knockout (Ahr-/-) mice versus Ahr+/+ mice exclusively at 28 dpn. Accordingly, AhR nuclear localization in granulosa cells, reflecting its activity in cells responsible for E2 synthesis, was much lower at 14 dpn than at 28 dpn in C57BL/6 mice. However, AhR signaling could be activated by exogenous ligands at both ages, as revealed by FICZ- and TCDD-induced Ahrr and Cyp1a1 expression in C57BL/6 mice. Nevertheless, TCDD impacted ovarian estrogenic activity only at 28 dpn. This age-related AhR action may be ligand-dependent, since FICZ had no effect on E2 synthesis at 28 dpn. In conclusion, AhR would not regulate ovarian estrogenic activity before the approach of puberty. Its activation by EDCs may be more detrimental to reproductive health at this stage than during infancy.


Assuntos
Ovário/fisiologia , Dibenzodioxinas Policloradas/toxicidade , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Citocromo P-450 CYP1A1/metabolismo , Disruptores Endócrinos/metabolismo , Estradiol/metabolismo , Estrogênios/farmacologia , Feminino , Células da Granulosa/efeitos dos fármacos , Ligantes , Camundongos , Camundongos Endogâmicos C57BL , Ovário/efeitos dos fármacos , Dibenzodioxinas Policloradas/metabolismo , Maturidade Sexual/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
16.
Life Sci ; 258: 118242, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32784056

RESUMO

AIMS: As the spermatogenesis process is targeted by cisplatin (Cis) that changes testicular morphology, alters sperm quality, and hence causes male infertility. This study investigated the possible therapeutic effects of l-carnitine (LC) on Cis impaired spermatogenesis's establishment during the prepubertal phase. MATERIALS AND METHODS: Ninety-six prepubertal Sprague Dawley male rats were divided into four groups. CONTROL GROUP: rats were injected with 0.9% saline solution intraperitoneally (i.p.). LC group: animals were injected for eight weeks, with 250 mg/kg/wk. LC (i.p.). Cis group: animals were injected with a single dose of 5 mg/kg Cis (i.p.). LC + Cis group: animals were pre-injected with LC 250 mg/kg 2 h before Cis injection. The rats were sacrificed at 37, 60, and 90 days old, and their testes were taken for biochemical, molecular, and histopathological studies. The motility, viability, morphology, and DNA fragmentation of sperm in adult rats were also measured. KEY FINDINGS: Group treated with LC and Cis showed an increase in antioxidant and hormonal activity compared to the Cis treated group in the pre and post-pubertal period. Moreover, there was an increase in sperm survival, motility, and DNA integrity. Furthermore, LC showed an increase in the anti-apoptotic and chromatin remodeling genes and a decrease in the pro-inflammatory genes. SIGNIFICANCE: LC could enhance the spermatogenesis process after exposure to Cis during the prepubertal phase by restoring the balance between reactive oxygen species and antioxidant activity, improving hormonal activity, sperm quality and DNA integrity, promoting protamination and blood-testis barrier integrity, and maintaining the testicular architecture.


Assuntos
Carnitina/farmacologia , Cisplatino/toxicidade , Infertilidade Masculina/prevenção & controle , Infertilidade Masculina/fisiopatologia , Maturidade Sexual/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Animais , Antineoplásicos/toxicidade , Carnitina/uso terapêutico , Infertilidade Masculina/induzido quimicamente , Masculino , Ratos , Ratos Sprague-Dawley , Maturidade Sexual/fisiologia , Motilidade Espermática/efeitos dos fármacos , Motilidade Espermática/fisiologia , Espermatogênese/fisiologia
17.
PLoS One ; 15(8): e0236146, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760084

RESUMO

The smalltail shark, Carcharhinus porosus, was the most abundant elasmobranch species in fisheries off Brazil's northern coast (BNC) in the 1980s, but its population has been declining since the 1990s. For this reason, a demographic analysis is necessary to determine the extent of this decline and the fishing effect on the BNC's population. Therefore, we performed a stochastic demographic analysis of the population in the BNC, and considered its global center of abundance. Smalltail shark specimens (n = 937) were collected with gillnets in Maranhão state, eastern BNC, in the 1980s with sizes ranging between 29.6 and 120.0 cm total length. Most of the individuals (90.6%) caught were juveniles (< 6 years-old), and the mortality and exploitation rates showed that the species was overexploited (92.3% above the fishing mortality corresponding to the population equilibrium threshold). The smalltail shark's biological characteristics, such as slow growth and low fecundity, demonstrate that it is one of the least resilient species among similar sized coastal sharks in the region. All these factors yielded an annual decrease of 28% in the intrinsic population growth rate, resulting in a population decline of more than 90% in only 10 years, and much higher for the current period. This set of features comprising fishing recruitment occurring upon juveniles, overfishing, and intrinsically low resilience make the population unable to sustain fishing pressure and severely hamper biological recruitment, thus causing this drastic population decline. Furthermore, several local extinctions for this species in the northeastern and southeastern regions of Brazil highlight its concerning conservation scenario. Therefore, since similar fisheries characteristics occur throughout its distribution range, C. porosus fits the criteria E of the IUCN Red List for a critically endangered species and urgent conservation measures are needed to prevent its extinction in the near future.


Assuntos
Distribuição Animal , Espécies em Perigo de Extinção/estatística & dados numéricos , Pesqueiros/estatística & dados numéricos , Dinâmica Populacional/estatística & dados numéricos , Tubarões/fisiologia , Fatores Etários , Animais , Brasil , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Espécies em Perigo de Extinção/tendências , Fertilidade/fisiologia , Pesqueiros/tendências , Dinâmica Populacional/tendências , Maturidade Sexual/fisiologia
18.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(7): 747-752, 2020 Jul 06.
Artigo em Chinês | MEDLINE | ID: mdl-32842297

RESUMO

Objective: To examine the prospective association of pubertal timing and tempo with depressive symptoms in adolescents. Methods: Since 2013, 2 084 students in grade 1-3 were selected from two primary schools in Bengbu, Anhui Province were selected by using convenience sampling method to establish the adolescence pubertal development cohort. Followed up for 6 years, physical examination, secondary sexual development evaluation (testicular volume for boys and breast development for girls) and depressive symptoms were evaluated biennially. Non-linear growth model was used to estimate pubertal timing and tempo for boys and girls respectively. Depressive symptoms were interviewed by using the Short Mood & Feeling Questionnaire (SMFQ) at baseline and Mood & Feeling Questionnaire (MFQ) during follow-up for students in grade 1-2. Children Depression Inventory (CDI) was used for students in grade 3 at baseline and during follow-up. Depressive symptom scores were standardized by using the Z-score method. Multivariate linear regression model was used to analyze the predictive effects of modeling pubertal timing and tempo on depressive symptoms of adolescence boys and girls. Results: There were 1 909 students with complete questionnaire and puberty development information, including 1 052 boys (59.19%) and 857 girls (43.81%), with average age about (13.94±0.87) years and 91.60 percent follow-up rate. The average modeling pubertal timing of girls (11.25 years) was earlier than that of boys (12.70 years), and the average pubertal tempo of girls about 1.47 Tanner stage/year was faster than that of boys about 1.28 Tanner stage/year. After controlling for depressive symptoms, maternal education and adverse childhood experiences at baseline and age, body mass index (BMI) classification and sleep time during follow-up, this predictive effect of pubertal timing and tempo on depressive symptoms was only significant among girls. Compared with girls with on time pubertal timing, girls in the delay timing group had a lower level of depressive symptoms (ß=-0.19, 95% CI:-0.34,-0.01). Compared with girls in average pubertal tempo group, the fast tempo group associated with an increasing risk of depressive symptoms (ß=0.23, 95%CI: 0.05, 0.40), while the slow tempo group associated with an decreasing risk of depressive symptoms (ß=-0.21, 95%CI:-0.39,-0.03). Insignificant effects were found in puberty timing and tempo on depressive symptoms of boys (P>0.05). Conclusion: Fast pubertal tempo increases the risk of development of depressive symptoms of adolescent girls. There is no predictive effect of pubertal timing and tempo on depression symptoms of adolescent boys.


Assuntos
Puberdade , Maturidade Sexual , Adolescente , Criança , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Estudos Prospectivos , Inquéritos e Questionários
19.
Wiad Lek ; 73(6): 1194-1198, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32723952

RESUMO

OBJECTIVE: Іntroduction: The absence of diagnostic of the female sex organs in time can lead to serious disoders of the female athletes' reproductive system. There is few information in the literature about morphological evolution of the female sex organs, in particular, the uterus under the influence of sports. The aim: To determine the peculiarities of linear sonographic dimensions of the uterus, its position and shape in the acrobats of the Ukrainian ethnic group of high level of sportsmanship in different periods of puberty. PATIENTS AND METHODS: Materials and methods: 122 acrobats of high level of sportsmanship and 126 girls who have not played sports were examined. The girls' passport age was between 8 and 21 years old. In order to determine belonging to the Ukrainian ethnic group, all surveyed girls were given questionnaires where they were required to indicate the nationality and place of birth of their parents and grandparents. All girls were devided into three groups according to their biological age: athletes of prepubertal period of ontogenesis, duting puberty and athletes of postpubertal period of ontogenesis. Internal sex organs of all girls were examined by ultrasound diagnostic system of expert class Voluson 730 Pro (ATL, Austria) using a convex sensor RAB2-5L. The uterus was examined by the following program: determined its position and shape and 3 linear dimensions (length, width and thickness). The analysis of the obtained results was carried out in the licensed package Statistica 5.5 using nonparametric methods of estimation of indicators. RESULTS: Results: The monitoring of the growth and development of the uterus in different ontogenetic periods in acrobats and women who are not involved in sports was analysed. We found, that the length of the uterus at all stages of puberty in acrobats was significantly less than in the girls of the control group. The width of the uterus was statistically significantly smaller in female athletes in the pre- and post-pubertal periods, and in puberty. The thickness of the uterus under the influence of acrobatic sports activity does not undergo significant changes in all periods of ontogeny. CONCLUSION: Conclusions: Features of competitive activity in sports acrobatics as well as the result of sports selection lead to the delay of sexual development and, as a consequence, to the retardation of development of the uterus in all periods of puberty.


Assuntos
Grupos Étnicos , Ovário/diagnóstico por imagem , Adolescente , Adulto , Criança , Feminino , Humanos , Maturidade Sexual , Ultrassonografia , Útero , Adulto Jovem
20.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(7): 762-767, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32669175

RESUMO

OBJECTIVE: To study the association of body fat ratio with precocious puberty in girls. Previous studies have shown that body mass index (BMI) is associated with the girls' age of puberty but have not revealed the association of body fat ratio with age of puberty. METHODS: Based on the consensus on the diagnosis and treatment of central precocious puberty (CPP), 128 children with precocious puberty who were admitted to the hospital from July to August, 2017, were divided into a CPP group with 87 children and a peripheral precocious puberty (PPP) group with 41 children. A total of 51 girls without any puberty development signs were enrolled as the control group. Dual-energy X-ray absorptiometry was used to measure the body fat ratios of upper limbs, legs, trunk, android area, gynoid area, and the whole body. The association between body fat ratios and precocious puberty was analyzed with reference to age, BMI, BMI-Z score, bone age, ovarian volume, and hormone levels. RESULTS: Compared with the control group, the CPP and PPP groups had significantly higher body fat ratios of upper limbs, legs, trunk, android area, gynoid area, and the whole body, legs/whole body fat ratio, and (upper limbs+legs)/trunk fat ratio (P<0.05), while there were no significant differences in the above body fat ratios and fat distribution indicators between the CPP and PPP groups (P>0.05). For the girls with precocious puberty, the high body fat ratio group had significantly higher luteinizing hormone (LH) base value, luteinizing hormone releasing hormone (LHRH)-stimulated LH peak value, and LH/follicle-stimulating hormone peak value than the low body fat ratio group (P<0.05). Compared with the control group, both the high body fat ratio and low body fat ratio groups had a significantly higher LH base value (P<0.05). CONCLUSIONS: The increase in body fat may be a factor inducing precocious puberty in girls, but further studies are needed to determine the mechanism.


Assuntos
Puberdade Precoce , Tecido Adiposo , Criança , Feminino , Hormônio Foliculoestimulante , Hormônio Liberador de Gonadotropina , Humanos , Hormônio Luteinizante , Maturidade Sexual
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