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The novel since the nineteenth century has displayed a thorny ambivalence toward the question of having children. In its representation of human vitality it can seem to promote the giving of life, but again and again it betrays a nagging doubt about the moral implications of procreation. The Novel and the Problem of New Life identifies this tension as a defining quality of the modern British and European novel. Beginning with the procreative-skeptical writings of Flaubert, Butler, and Hardy, then turning to the high modernist work of Lawrence, Woolf, and Huxley, and culminating in the postwar fiction of Lessing and others, this book chronicles the history of the novel as it came to accommodate greater misgivings about the morality of reproduction. This is the first study to examine in literature a problem that has long troubled philosophers, environmental thinkers, and so many people in everyday life.
The study of Eurocentrism has become a hallmark of postcolonial International Relations theories. Of particular concern in this literature has been the resilience of Eurocentrism despite conscious efforts to move towards a post-Eurocentric understanding of world politics. This study argues that while existing works have highlighted many of the reasons why Eurocentrism persists today, it has not been sufficiently identified and conceptualised. In particular, why some policy actors, who have a vested interest in moving beyond Eurocentrism, inadvertently reproduce Eurocentrism? This article proposes to distinguish between different types of inadvertent reproductions. In particular it highlights rhetorical critique, deconstruction, decentring and dehierarchising, as different ways to critique, inadvertently reproduce and partially modify Eurocentrism. To illustrate this situation, this article looks at Turkey's migration policies and documents how Turkish governing elites have openly claimed the need to upend the Eurocentric order, yet have reproduced it in practice.
(i) to examine demographic and health characteristics of women of reproductive age on a vegan diet in Australia and compare these to the general population, (ii) to identify sources and intake of vitamin B12, and compare intake to current recommendations (iii) examine associations between participant characteristics and adequacy of vitamin B12 intake.
In this cross-sectional study data was collected via an online survey. Demographic and health characteristics of women on a vegan diet were compared to women in the general population (using Australian Bureau of Statistics data). Intake of vitamin B12 was estimated using a food frequency questionnaire and estimation of supplemental intake.
Participants (n1530) were women 18-44 years who had been on a vegan diet for at least six months.
While Body Mass Index, smoking habits and intakes of fruit and vegetables compared favourably to the general population, 26% of respondents had estimated intakes of vitamin B12 below recommendations. Analyses of relationships between vitamin B12 intake and participant characteristics revealed that the strongest predictor of intake was supplementation (p<0.001), however, 25% had not supplemented with vitamin B12 in the past three months.
The vitamin B12 intakes of a substantial proportion of Australian women of reproductive age consuming a vegan diet do not meet the recommended intake, which could adversely affect their health, and, if they are pregnant or lactating, that of their infants too. There is a need for further research in this area to identify effective strategies to address this situation.
The peacock-tail shrimp Ancylocaris brevicarpalis Schenkel, 1902, is an obligate symbiont of sea anemones and well known for its remarkable colouration. Yet, very little information is available about its population structure and life-history traits, including reproductive parameters (fecundity, embryo volume and reproductive output). A total of 574 individuals were collected from the Gulf of Mannar, Tamil Nadu, India between February 2017 and July 2018, out of which 214 were males (37.28%), 355 were females (61.84%), and 5 (0.87%) juveniles. The highest percentage of individuals were observed in the post-monsoon season (38.10%) followed by monsoon (34.85%), pre-monsoon (15.02%), and summer seasons (12.01%). The overall sex ratio was skewed towards female individuals (0.55 male: 1 female). Fecundity was higher in females carrying early-stage embryos and embryo volume did increase, but not statistically significantly from early to late stages. The reproductive output was negatively allometric to the mean female body weight. The present study provides first-of-its-kind information on the population as well as individual-level reproductive characteristics of A. brevicarpalis.
Histological examination of Atka mackerel ovotestes reveals the possibility of intersexuality. Individuals with bisexual gonads have been caught in the North Pacific near the south-east coast of the Kamchatka peninsula. While intersex appeared to be normal females with developing ovaries, histological analysis showed the presence of both female and male tissue in the same gonad. Specifically, primary growth, cortical alveolar and primary vitellogenic oocytes were located among spermatogonia cysts. The prevalence of intersexuality in the population was less than 0.1%.
The reproductive biology and embryonic development of Mustelus higmani were examined between January 2015 and December 2016 in the south-eastern Caribbean. Captures comprised 813 females (23.2–72.5 cm TL), and 960 males (22.6–62.5 cm TL). The total length at 50% maturity was estimated as 47.8 and 47.5 cm for females and males, respectively. Uterine fecundity ranged from 1 to 8 embryos and ovarian fecundity between 1 and 9 vitellogenic follicles. The time of parturition and mating season of M. higmani may occur throughout the year, peaking between November and February. The presence of pre-ovulatory ovarian follicles along with advanced embryos indicates an annual reproductive cycle for female M. higmani. The main embryonic development stages were recorded in the samples, from uterine eggs (1 to 6 per female) to term embryos (23.0–26.0 cm TL). The transition between placental pre-implantation and post-implantation occurs when embryos have attained a TL of 5.0–6.0 cm. The observation of abundant uterine histotrophic secretions in late pregnant and post-partum females demonstrates that histotrophy may intensify close to birth in this species. The local population of M. higmani appears to have relatively high productivity; nonetheless, this species is heavily harvested and lacks management measures in the study area.
The mating system and mating strategies of a species refer to the behavioral strategies used to obtain reproductive partners and ensure reproductive success. Common determining factors of mating systems and strategies are: the manner of mate acquisition, the number of mates obtained by an individual, as well as the absence or presence and duration of parental care. In mammals, the energetic investments in gametes and rearing offspring are typically larger for females than for males. Mate selection is thus a much more important decision for females than for the rather indiscriminate males. This dichotomy results in sexual selection, which in turn is determined by male–male competition for access to females, as well as female mate choice. Because receptive females are generally considered the limiting resource in reproduction, males face intrasexual competition for mates. In a multitude of mammalian species, including bears, this has resulted in pronounced sexual size dimorphism and polygamous mating systems. Despite common characteristics (e.g. sexual size dimorphism, polygamy), variation in mating systems and strategies occur among bear populations and species.
Size-frequency analysis of the echinoid Echinocyamus pusillus from six offshore areas in the southern North Sea and eastern English Channel reveal five distinct cohorts, suggesting a lifespan of five years. In all six individual areas one or more year-groups are absent, due to the unsuccessful recruitment of planktonic larvae to the seabed in some years, giving a false impression of a shorter lifespan. A relatively long lifespan and planktotrophic larval development are remarkable for such a small species, which reaches a maximum test length of 7.3 mm in the area, such traits being more typical of large-sized macrobenthic species. The feeding mode is akin to that of many meiobenthic taxa. The architecture of the test confers exceptional strength and resilience to mechanical perturbation.
Rivulidae comprises a family of fish largely distributed in Brazil that includes 201 species, of which 125 are considered endangered. This fact emphasizes the need for development of conservation strategies including studies on genetics and reproduction. In this paper, we describe aspects of biology and reproduction of the rivuliid species Hypsolebias sertanejo. We outline the reproductive behaviour of this species under laboratory conditions, analyze ploidy status by flow cytometry, describe reproductive behaviour and performance and test dry and wet incubation of eggs. Although H. sertanejo showed well known patterns of reproductive behaviour, we verified many peculiarities inherent to its reproductive biology. As expected, most individuals were diploid (87.71%), however 14.29% were considered mosaics. Although no sterility was observed within mosaics, infertility of these fish was not fully evaluated. Hatching rate of the eggs collected was very low following both dry and wet incubation (5.04 and 3.79%, respectively). These results provide interesting information regarding the reproductive success of this species, and suggest that chromosomal abnormalities described may reduce the survival of H. sertanejo under natural conditions, limiting the perpetuation of this species, and emphasizing the need for more preservation efforts, including artificial propagation and gene banking.
Mating behaviours for two species of dioecious eutardigrades: a strain of Paramacrobiotus sp. and Macrobiotus shonaicus (Stec et al., 2018) have been recorded previously, and observations have indicated that spermatozoa of both species are first released into the environment, then swim through the cloaca of the females and into the spermatheca. The fusion of gamete nuclei has not yet occurred in a laid egg. Therefore, it has been suggested that fertilization is completed externally as the egg is released into the environment before the nuclei of the gametes fuse. In the present study, the spermatozoa of both Paramacrobiotus sp. and M. shonaicus spermatozoa underwent morphological changes during reproduction. In morphometrical analyses of testicular spermatozoa, the tail, mid-piece, nucleus, and acrosome were significantly longer in Paramacrobiotus sp. compared with M. shonaicus. The nuclei of both the testicular and spermathecal spermatozoa were equally coiled, but the latter had shorter tails in both species. These spermatozoa were present on the surface of the egg chorion after oviposition. The tip of the acrosomes lay buried in the chorion, suggesting that penetration had occurred. We also proposed that the reduced tail is a conserved trait, at least in Macrobiotidae.
Sardinella aurita has become an important source of fish protein-intake in NW African countries, where one stock is considered from Morocco to south Senegal, performing seasonal reproductive migrations along the coast. Although data are limited for the fisheries involved and for life-history knowledge of the species in the area, a precautionary approach is recommended to avoid overexploitation. Commercial landings of round sardinella produced by the European freezer-pelagic trawlers operating in Mauritanian waters were analysed between May 2004 and February 2012. The length-weight relationships (LWRs) (N = 40,725) did not show significant differences between sexes. Ripening round sardinellas were present throughout the year, but spawning effort rose between June and December. The length at first maturity for males and females was estimated at 27.7 cm TL (2.1 years) and 28.1 cm TL (2.2 years), respectively. Ages were interpreted from otoliths, varying from 0 to 8 years. Von Bertalanffy growth parameters resulted in non-statistically significant differences between sexes (P = 0.28). Natural mortality was estimated at ~0.63 year–1. The results provide important biological information for fisheries assessment of a species that plays an important key role in the current climate change scenario and for the economies of the riparian countries.
Widespread across open lands and cities of Europe, Africa, and Asia, the common kestrel (Falco tinnunculus) is one of the most abundant and studied birds of prey. This book brings together and synthesises the results of research on kestrels for professional ornithologists and scientists that seek to consolidate a vast body of literature. It is also a reference for those readers who may not have the depth of scientific knowledge to navigate new fields of scientific enquiry. It examines many aspects of the species' biology, from the reproductive strategies to the behavioural and demographic adaptations to changes of environmental conditions. It also discusses the roles of physiology and immunology in mediating the adaptability of kestrels to the ongoing environmental changes with a particular focus on contaminants. This volume presents new and exciting avenues of research on the ecology and behaviour of the common kestrel.
The number of birds breeding in a given area (breeding density) is affected by several abiotic and biotic factors. Availability of suitable nesting sites plays a major role in determining the size of the local breeding population of birds, particularly in those species, like the common kestrel, that do not build their own nests. Kestrels do actually use old nests of corvids or holes in buildings to breed. By provisioning kestrels with artificial nest boxes, it is possible to increase the number of breeding individuals and, possibly, the population size. However, a number of factors need careful consideration to evaluate a priori the characteristics of nest boxes and locations to install them and to assess a posteriori the effects of the nest box provisioning on the reproductive ecology and population dynamics of kestrels.
Age, growth and reproduction biology of the golden grey mullet, Chelon auratus (Risso, 1810) have been studied in the Istanbul Golden Horn area. Fish length ranged from 13.4–46.8 cm, and age from 1–10 years, respectively. The sex ratio (female:male) was 1:1.08. The length-weight relationship was estimated as W = 0.0127L2.89, W = 0.0099L2.97 and W = 0.0156L2.82 for both sexes combined, females and males, respectively. The von Bertalanffy growth equation parameters were: L∞ = 57.52 cm, K = 0.1 year−1, t0 = −2.24 year for pooled data. The gonadosomatic index (GSI) values indicated the major spawning period was between August and November, and the minor spawning peak between March and April. The highest GSI values were observed in September. The length and age of sexual maturity were estimated as 26.2 cm and 4 years for males and 24.1 cm and 3 years for females.
The suffrage and birth control movements are often treated separately in historical scholarship. This essay brings together new research to demonstrate their close connections. Many suffragists became active in the birth control movement just before and after the passage of the Nineteenth Amendment in 1920. The roots of suffrage arguments were deeply embedded in the same ideas that were foundational to the birth control movement: bodily freedom and notions of what constituted full and participatory citizenship. Beginning in the 1840s, women's rights reformers directly connected the vote to a broad range of economic and political issues, including the concept of self-ownership. Wide-ranging debates about individual autonomy remained present in women's rights rhetoric and were then repeated in the earliest arguments for legalizing birth control. The twentieth-century birth control movement, like the suffrage movement before it (which had largely focused only on achieving the vote for white women), would then grapple with competing goals of restrictive racist and eugenic arguments for contraception alongside the emphasis on achieving emancipation for all women.
Correct diagnosis of cause of death is necessary to suggest the most effective management interventions to reduce perinatal lamb mortality. Haemorrhage on the surface of the brain has been used as a field diagnostic tool to allocate lambs to a cause of death category, but the usefulness of this method was unclear. This study aimed to evaluate whether gross pathology was related to neuronal death and whether haemorrhage of the central nervous system (CNS) was distinct between differing causes of death, enabling indicators to be used in field diagnoses. Lambs dying from natural causes (n = 64) and from euthanasia (n = 7) underwent postmortem examination, then the brain and spinal cord were extracted and examined histologically. Histological changes consistent with neuronal death were not detected in any lamb. Haemorrhage of the meninges and/or parenchyma of the CNS occurred in all lambs. The age of the haemorrhage indicated that it occurred near the time of death in most lambs. Dilation of blood vessels varied in severity but appeared to be unrelated to causal diagnosis, severity of subcutaneous oedema, breathing or milk status. Moderate or severe dilation of blood vessels and haemorrhage of the CNS did not occur in all lambs with alternative clear indicators of dystocia and occurred in all death classifications, so it could not be used as diagnostic indicators for classification of cause of death. Dilation and haemorrhage were unrelated to neuronal damage and may have been artefactual. In conclusion, haemorrhage of the CNS was not indicative of neuronal damage and could not be used to distinguish between lambs with clear indicators of differing causes of death, so it is not recommended as a field diagnostic tool.
Sexual interaction is an important activity that determines the reproductive schedule of organisms and can ultimately influence the fitness traits of both sexes. Although the influence of sexual interaction on the fitness of females has been extensively determined, little is known about the effects on males, which often have different mating strategies and optimal mating regimes from those of females. To understand how mating regimes (timing and frequency) modulate the fitness in both sexes, we used spider mite (Tetranychus urticae) to investigate the influence of delayed mating and repeated mating on the fitness of male and female. For females, the unmated and the delayed mating females outlived those mated immediately after adult emergence. The repeated mating shortened the lifespan of females that mated at 1-day-old, but not that mated 7-day-old. However, no significant variation in lifespan was observed for males across different mating regimes. We found although delayed mating significantly reduced the daily reproductive rate of the females, there was no significant difference in lifetime reproduction of females across treatments because the delayed mating females increased their reproductive lifespan as a compensation. Our study highlighted that the time and frequency of sexual interaction showed a sex-specific consequence on male and female spider mites, indicating that sexual interaction incurs a higher cost to females which have a much lower optimal mating frequency than males.
Maternal undernutrition decreases sperm production in male offspring, possibly through insulin-like growth factor (IGF-I). To test this hypothesis, we fed pregnant Wistar rats ad libitum with a standard diet (CONTROL) or fed 50% of CONTROL intake, either throughout pregnancy (UNP), lactation (UNL, or both (UNPL). After weaning, male offspring (n = 10 per treatment) were fed a standard diet until postnatal day 160, when testes process for histological and molecular analyses. IGF-I immunostaining area and intensity in the testis were greater (P = 0.003) in the UNPL group compared to CONTROL, but lower in the UNP group (P < 0.0001). Levels of IGF-I receptor transcript were lower in the UNPL and UNL groups, compared to CONTROL. There were more Ki-67-positive germ and Sertoli cells, in all underfed groups than in CONTROL. Compared to CONTROL, frequency of spermatogenic cycle stage VII was lower in all underfed groups, and seminiferous tubule diameter was smaller in UNP and UNPL. Plasma FSH concentrations were greater in UNP male offspring compared to all groups (P = 0.05), whereas inhibin B concentrations were greater in UNP (P = 0.01) and UNL (P = 0.003) than in CONTROL or UNPL. Thus, prenatal undernutrition leads to a decrease in testicular IGF-I levels, whereas of pre- and postnatal undernutrition increased testicular IGF-I levels and decreased amounts of IGF-I receptor mRNA in adult offspring. We conclude that maternal undernutrition during pregnancy and lactation leads to long-lasting effects on adult male offspring testicular morphology, spermatogenesis, and IGF-I testicular system.
During weaning-to-estrus interval (WEI), the sows are usually fed with high feed level to improve the reproductive performance. However, the WEI has been reduced over the years which may reduce the impact of feed level on performance in the modern genetic lines. The aim of this study was to evaluate the effect of two feeding levels (moderate feeding level (MFL): 2.7 kg/day and high feeding level (HFL): 4.3 kg/day) and two diet types (gestation: 13.67 MJ/kg of metabolizable energy (ME) and 0.62% of standard ileal digestible lysine (SID Lys) and lactation: 14.34 MJ ME/kg and 1.20% of SID Lys) offered during the WEI on reproductive performance. In total, 19.0% of sows were excluded from the analysis due to feed intake below 75% (9.6% and 28.5% in MFL and HFL groups, respectively), remaining 254 primiparous and 806 multiparous sows. Follicular size and change in BW were measured in subsamples of 180 and 227 females, respectively. Data were analyzed considering the sow as the experimental unit. Feeding level, diet type, parity and their interactions were included as fixed effects, whereas the day of weaning was considered as a random effect. The feed intake of MFL and HFL groups averaged 2.5 ± 0.02 and 3.8 ± 0.02 kg/day, respectively. There was an interaction between feeding level and parity for daily feed intake. Within HFL, multiparous sows consumed 181 g/day more than primiparous sows (P < 0.01), but no difference was observed within MFL (P > 0.05). Both primiparous and multiparous sows lost proportionally less weight when fed HFL than MFL gestation diet during WEI. The percentage of weight loss was lower in HFL than in the MFL group in multiparous sows fed the lactation diet. The WEI was not affected by feeding level, diet type or its interaction (P > 0.05), but it was longer in primiparous than in multiparous sows (P = 0.001). There was no effect of feeding level, diet type, parity or their interactions on anestrus and farrowing rates. Multiparous sows showed greater follicular size, and greater numbers of total born and born alive piglets in the subsequent cycle than primiparous sows (P < 0.05). In conclusion, feeding weaned primiparous and multiparous sows with 4.3 kg/day of a gestation (58.78 MJ ME and 26.66 g SID Lys) or a lactation diet (61.66 MJ ME and 51.60 g SID Lys) does not improve follicular size and reproductive performance in the subsequent cycle.