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Introdução: padrões sexuais e reprodutivos são influenciados por fatores biopsicossociais. Dentre esses fatores, há a vulnerabilidade, conceito amplo, complexo e que determina maior atenção das políticas públicas. Objetivo: conhecer o perfil reprodutivo das mulheres que residem em uma área de alta vulnerabilidade na cidade de Curitiba-PR. Metodologia: descritivo, documental de caráter analítico observacional transversal. Coleta e análise de dados das Declarações de Nascidos Vivos (DNV) na Unidade de Saúde do Capanema e análise de dados públicos fornecidos pelo IBGE. Resultados: foram analisados 1199 DNVs, sendo 1011 mulheres com idades entre 13 e 49 anos, compreendidos entre os anos de 2003 a 2018. Foi possível a análise da Taxa de Fecundidade Total (TFT), via de parto, estado civil e escolaridade das parturientes. Discussão: a menor TFT foi apresentada na faixa etária de 13 a 15 anos (1,05 filhos/mulher) e a maior entre 36 a 49 anos (4,47 filhos/mulher). A via de parto vaginal correspondeu a 64% dos partos, enquanto que a via cirúrgica por cesárea aconteceu em 36% dos casos. Em relação à escolaridade, 3% apresentaram-se como analfabetas; 48% possuíam nível fundamental; 40% nível médio completo e 9% possuíam nível superior completo ou incompleto. Houve 0,5% de omissão da que escolaridade no momento do preenchimento dos dados. Os dados coletados sobre o estado civil foram considerados inconclusivos. Conclusão: Conclui-se que a Taxa de Fecundidade da população estudada está acima da Taxa de Fecundidade Total projetada para 2015 no Brasil nas faixas etárias acima de 19 anos e da taxa de fecundidade ideal para que haja uma reposição da população segundo o DATASUS (2021). Tais dados podem estar relacionados com a vulnerabilidade da comunidade em questão, corroborando com estudos que relatam maiores taxas de fecundidade relacionada a menor renda e menor escolaridade.

Introduction: sexual and reproductive patterns are influenced by biopsychosocial factors. Among these factors, there is vulnerability, a broad and complex concept that requires greater attention from public policies. Objective: to know the reproductive profile of women who live in an area of high vulnerability in the city of Curitiba-PR. Methodology: descriptive, documental, cross-sectional observational analysis. Collection and analysis of data from the Birth Certificates (BC) at the Capanema Health Unit and analysis of public data provided by the IBGE. Results: 1199 BCs were analysed, with 1011 women aged between 13 and 49 years old, between the years 2003 and 2018. It was possible to analyse the Total Fertility Rate (TFR), mode of delivery, marital status and level of education of the parturients. Discussion: the lowest TFR was observed in the age group from 13 to 15 years old (1.05 children/woman) and the highest between 36 to 49 years old (4.47 children/woman). Vaginal delivery corresponded to 64% of deliveries, while surgical caesarean section occurred in 36% of cases. Regarding schooling, 3% were illiterate; 48% had a fundamental level; 40% completed high school and 9% had completed or incomplete higher education. There was 0.5% omission of schooling attainment at the time of filling in the data. Data collected on marital status were considered inconclusive. Conclusion: it is concluded that the Fertility Rate of the studied population is above the Total Fertility Rate projected for 2015 in Brazil in the age groups above 19 years and the ideal fertility rate so that there is a replacement of the population according to DATASUS (2021). Such data may be related to the vulnerability of the community in question, corroborating with studies that report higher fertility rates related to lower income and lower education.

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We studied the spawning ecology of Stegastes sanctipauli, a damselfish endemic to the small and remote St Peter and St Paul's Archipelago (Brazil), aiming to determine the main correlates of reproductive success, as inferred from rates of egg losses along a spawning season. New clutches appeared mostly in the last quarter moon, when egg predation intensified. Predation by heterospecifics, particularly Halichoeres radiatus (Linnaeus, 1758), accounted for most egg losses, while filial cannibalism showed negligible influence. Predation pressure was highest for larger nests with higher initial density of eggs. Hatching of eggs occurred close to the new moon (i.e., ~5 days after spawning). Most nests occur in shallow reefs (<16 m depth), where main food resources for adults (turf algae) are concentrated, but abundance of egg predators, particularly H. radiatus, is also highest. This latter result suggests that the spawning activity of S. sanctipauli is influenced by the trade-offs between food accessibility by adults and egg predation risk. The patterns recorded here are similar to those known for other tropical damselfish species and may reflect strategies for attenuating predation pressure over new fry and eggs.

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Multiple paternity (MP) in the brown smooth-hound shark (Mustelus henlei) was assessed in 15 litters (15 mothers and 97 embryos) collected in the northern Gulf of California of which 86.7% were sired by more than one male (i.e., from 2 to 4 sires). When taken together with results from previous studies, this record indicates that there is regional variation in MP in M. henlei in the northeastern Pacific. This pattern is associated with variations in the reproductive traits of each population (e.g., female size and litter size). In the Gulf of California, the results of a generalized linear model (GLZ) indicated that the litters of larger females had a higher probability of MP compared to those of smaller females.

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Social context is a key factor affecting sexual behaviour and cannot be neglected in gregarious species, such as triatomine blood-sucking bugs. Here we study the influence of the social context on the sexual reproductive behaviour of males and females of Rhodnius prolixus Stål. Specifically, we identify and compare the frequencies and sequence of sexual behaviours exhibited by a focal pair in presence or absence of a male audience. We expect that in presence of a male audience females increase their selectiveness level since the risk of losing infertile eggs decreases in presence of more candidates and females can benefit from copulating with a better quality male. Besides, in presence of potential rivals, we expect changes in the sexual behaviour of focal males, associated to a reduction in the risk of sperm competition. As expected, in presence of a male audience, females significantly increased the exhibition of rejection behaviour. Moreover, focal males exhibited shorter latencies to mount the female, longer duration of copula, and differences in their stereotyped behaviour exhibited during copula. We discuss the influence of the social context on the reproductive behaviour of females and males of R. prolixus.

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The three-spined stickleback is a ubiquitous fish of marine, brackish and freshwater ecosystems across the Northern hemisphere that presents intermediate sensitivity to copper. Male sticklebacks display a range of elaborate reproductive behaviours that include nest construction. To build the nests, each male binds nesting material together using an endogenous glycoprotein nesting glue, known as 'spiggin'. Spiggin is a cysteine-rich protein and, therefore, potentially binds heavy metals present in the environment. The aim of this study was to investigate the capacity of stickleback nests to accumulate copper from environmental sources. Newly built nests, constructed by male fish from polyester threads in laboratory aquaria, were immersed in copper solutions ranging in concentration from 21.1-626.6 µg Cu L(-1). Bundles of polyester threads from aquaria without male fish were also immersed in the same copper solutions. After immersion, nests presented higher amounts of copper than the thread bundles, indicating a higher capacity of nests to bind this metal. A significant, positive correlation between the concentration of copper in the exposure solution and in the exposed nests was identified, but there was no such relationship for thread bundles. Since both spiggin synthesis and male courtship behaviour are under the control of circulating androgens, we predicted that males with high courtship scores would produce and secrete high levels of the spiggin protein. In the present study, nests built by high courtship score males accumulated more copper than those built by low courtship score males. Considering the potential of spiggin to bind metals, the positive relationship between fish courtship and spiggin secretion seems to explain the higher amount of copper on the nests from the fish showing high behaviour scores. Further work is now needed to determine the consequences of the copper binding potential of spiggin in stickleback nests for the health and survival of developing embryos.

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In presence of a decrease in the catch from Infiernillo reservoir, Michoacán-Guerrero, Mexico, age and growth of tilapia Oreochromis aureus (Steindachner 1864) were estimated, as indispensable attributes for fishery management. Evaluations included scales and opercular bones readings and length frequency analysis. The population structure was determined too. Due to the great variation of tilapia individual growth and with the objective to have reliable growth estimations, linearized, non-parametric and non-linear methods were used and their applicability discussed. Comparison of ages determined from these methods revealed that opercular bones readings had advantages over scales. Reproduction and competition for space and food were considered as responsible factors for ring-formation on tilapia hard structures. The non-linear method was considered the best for modelling populations highly variable, which is characteristic of tilapia and tropical fish with multiple spawns. The growth parameters estimated were Linfinity = 479 mm, K = 0.46/yr, t0 = -0.055 yr. The tilapia population in Infiernillo reservoir is dominated by juveniles less than 1.5 years old. The fishery activity is affecting the tilapia population growth because are caught when they have not yet spawned. Therefore, this fishery is in urgent need of regulation. Increasing the mesh size of the gill nets might contribute to protect the reproductive potential of the stock.

Ante el continuo decremento en las capturas de tilapia de la presa Infiernillo, Michoacán-Guerrero, México, se estimó la edad y crecimiento de Oreochromis aureus (Steindachner 1864) que son atributos indispensables que deben conocerse para realizar el manejo de la pesquería. La evaluación incluyó la lectura de marcas de crecimiento en escamas y opérculos, y el análisis de frecuencia de tallas. También se estimó la estructura de edad de la población. Debido a la alta variabilidad individual en el crecimiento que presentan las tilapias y a fin de obtener estimaciones fidedignas de crecimiento, diferentes métodos lineales, noparamétricos y no-lineales fueron usados y su aplicación discutida. Los opérculos presentaron ventajas sobre las escamas en la determinación de edad. La reproducción y la competencia por espacio y alimento fueron consideradas factores responsables de la formación de marcas en las estructuras duras de tilapia. El modelo no-lineal fue considerado el mejor para modelar el crecimiento de poblaciones altamente variables como la de tilapia y otros peces tropicales que presentan múltiples desoves. Los parámetros de crecimiento estimados fueron: L∞ = 479 mm, K = 0.46/yr, to = -0.055 yr. La población de tilapia en la presa Infiernillo está dominada por juveniles menores de año y medio de edad. La actividad pesquera está afectando el crecimiento de la población de tilapia, puesto que éstas son capturadas antes de que desoven. La pesquería requiere urgentemente una regulación. Un incremento en la abertura de malla de las redes agalleras con que es capturada, podría contribuir a proteger el potencial reproductivo del stock.

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There is limited information on the reproductive behaviour of the Maned wolf Chrysocyon brachyurus. Although it is a monogamous species, little is known about the ♂'s role in the rearing of pups. In 1994 a comparative study of the behaviour of two ♀♀ with new-born pups was carried out at Belo Horizonte Zoo to try to establish the ♂'s role in rearing: one ♀ was housed alone with her pups throughout the observation period; the other ♂ was housed with the ♀ and pups for the first month and alone with the pups for the second month of observation. The applied methodology for behaviour evaluation was instantaneous sampling (scan). The behaviour of each adult was recorded at one-minute intervals. Location in the enclosure and spatial proximity were also recorded. The results suggest that Maned wolves are inactive for large parts of the day and that they prefer secluded areas within an enclosure. The results also suggest that only the ♂ is directly involved in rearing the offspring and that ♀ participation is limited to protection only. The time that the ♂ stays with the pups is at a maximum on the days immediately following birth, but this time decreases considerably as the pups grow. At around day 50, when lactation has ceased, contact between the ♂ and pups is minimal and the pups have their own resting places within the enclosure. These resting places, inside the burrows or thick vegetation, are rarely shared with others.