This study examines the reproductive strategies of the Pill-box crab, Halicarcinus innominatus, at the Oaro Platform (24 km south of the Kaikoura Peninsula, New Zealand). As necessary components of reproductive strategies, the population dynamics, reproductive biology and mating behaviour of H. innominetus were examined from December 1997 through December 1998. There were obvious sexually dimorphic differences in secondary sexual traits in this species. Both males and females display a wide range of sizes over which individuals can moult to maturity. H. innominatus females displayed continuous breeding throughout the year, resulting in continuous recruitment. Females were found to outnumber males in each month. However, when comparisons were made between mature males and females with different brood stages (i.e. 0-5), males outnumbered each female type in each month. Investigations into the reproductive biology of H. innominatus females revealed that brood development and ovary development were in phase. This resulted in the ability of females to produce several broods in quick succession. Ovary development began before the moult to maturity, allowing for immediate production of a brood after the moult to maturity. Egg incubation periods were dependent on water temperature, being longest in the winter and shortest in the summer. Egg numbers were found to increase with female body size, but mortality of eggs through development was apparent. Sperm storage was found to occur in this species with possible layering of different ejaculates. Copulations were only observed between males and females in hard-shell conditions. Males mated more often with females carrying stage 5 broods, but also mated with all other female types, including pre-pubescent females. Postcopulatory mate guarding only occurred with stage 5 females. Males can detect females of different reproductive condition, which seems to be linked to the developmental stages of the females' ovaries. In conclusion, H. innominatus males seem to have two tactics to their reproductive strategies: mating with any receptive female, but only guarding stage 5 females.

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The evolution of wind pollination (anemophily) has occurred at least 65 times in the flowering plants and over 10% of angiosperm species are wind pollinated. However the pollination and mating of anemophily species is poorly understood, particularly in comparison with animal-pollinated species. My thesis employs a range of approaches and tools to examine the evolution and ecology of wind pollination. These include comparative analyses, theoretical modeling, field and glasshouse experiments, the use of genetic markers and quantitative genetics. Experimental studies on diverse taxa were used to address questions concerned with the efficacy of outcrossing mechanisms, the ecological and demographic context of pollination and mating, and the plasticity of sex allocation. Comparative analyses indicated that wind pollination is correlated with unisexual flowers, reduced ovule number, small unshowy flowers, an absence of nectar, and open habitats. These analyses also demonstrated that anemophily originates more often in lineages with unisexual flowers. This suggests that wind pollination evolves in diclinous taxa as a mechanism of reproductive assurance because autonomous selfing is mechanically precluded. Empirical data on stigmatic pollen loads in 19 anemophilous species challenge the widespread assumption that anemophilous plants commonly have uniovulate flowers because they capture few pollen grains. Further, a model based on floral costs and the aerodynamics of pollen capture demonstrated that when flowers are inexpensive it is optimal to produce many flowers each with few ovules, because this allows more efficient sampling of the airstream. Manipulative field experiments on seven Carex species indicated that neither monoecy nor protogyny, two putative outcrossing mechanisms, are effective at limiting selfing. Based on these results I suggest that geitonogamy can provide reproductive assurance in anemophilous species with unisexual flowers. Field experiments and the application of sex-specific markers in Rumex nivalis revealed that the local neighbourhood of maternal plants affects pollination intensity and progeny sex ratios. Finally, I demonstrated that plant density in Ambrosia artemisiifolia affects stigmatic pollen loads but not outcrossing rates. Through a quantitative genetics experiment in A. artemisiifolia, I detected significant genetic variation for plasticity in sex allocation, potentially enabling adaptive adjustment of sex allocation to local environmental conditions.

The eastern oyster (Crassostrea virginica Gmelin 1791) has great ecological and economic importance but populations have declined, especially in Chesapeake Bay, to historically low numbers. Hatcheries strive to produce oysters with beneficial characteristics for supplementation and commercial purposes, both natural and stimulated mass spawning. Unequal contribution of parents in mass spawnings potentially can lead to high levels of inbreeding and a loss of beneficial characteristics in offspring. In this study, we determined microsatellite genotypes for parents (n^parents =24, 49, and 77 parents) and progeny (n=96 each) of three hatchery-produced families and used the data for parental assignment. We observed the presence of more than two alleles per locus for some offspring, yet because genetic analysis software only allows for a maximum of two alleles per locus, we chose the two alleles with the strongest signals. For the three parent “populations,” 71% of alleles had frequencies of <0.05 and observed heterozygosities were lower than expected by an average factor of 0.27. Inbreeding within the various parent populations was similar across the three families ranging from F^IS 0.26–0.43. In all three families, the offspring exhibited greater levels of genetic diversity and lower inbreeding levels than the parents (F^IS 0.14–0.21), and in some cases offspring exhibited alleles that were not present in the parents. Variance in the number of offspring produced per parent was observed for all families and in general, <10% of potential parents (generally 2-5 females and 1-3 males) produced >10% of the offspring. Reproductive success for spawning parents, N^b, determined by three methods, ranged from 0.07 to 0.27. As the number of parents per family increased, a higher proportion of parents failed to produce offspring. Across all three families, the average effective number of breeders was N^b = 7.1 and the level of reproductive success was inversely proportional to the number of potential parents. This finding implies that to maintain high levels of diversity and beneficial characteristics in the offspring (and to avoid the chance of unintentional inbreeding), hatcheries should perform more spawnings with fewer parents.

Detta examensarbete handlar om hur par upplever att vara infertila och deras längtan efter att bli föräldrar. Infertilitet väcker starka känslor hos paret och är någonting som de själva inte kan styra över. Arbetet baseras på tio vetenskapliga artiklar som funnits via sökningar i databaser som låg till grund för analysen. Av dessa artiklar delades deras resultat in i tre teman med tre underteman vardera. Dessa teman svarar på arbetets syfte i resultatdelen, det vill säga parets upplevelse av infertilitet. Resultatet visade att par upplevde infertiliteten som en omtumlande tid i livet då de kände sig maktlösa i situationen. Par försökte hitta en annan mening i vardagen och det var vanligt att istället satsa på karriär, utbildning, resor eller hobbys. Infertiliteten påverkade individen och paret i och med de känslor som uppkom. Detta medförde tankar på om relationen exempelvis skulle vara hållbar utan barn. Resultatet visade även att par upplevde ett tryck ifrån vänner och familj. De hade svårt att glädjas när vänner och syskon fick barn och kände skuld över att inte kunna erbjuda deras föräldrar barnbarn. Stöd i olika former efterfrågades där andra par i samma situation tycktes vara de enda som förstod vad de genomgick. Hälso- och sjukvården sågs som en viktig källa till information. Det är tydligt att infertilitet påverkar paret med många känslor och påfrestningar men i slutändan har det dock visats stärka paret på ett eller annat sätt. I våra slutsatser framkommer det att sjuksköterskan har en viktig roll i mötet med paret. Genom att sjuksköterskan tillämpar personcentrerad vård ges  örutsättningen att förhindra vårdlidande. / Background: Infertility is more common than many people think and can be due to various factors. The occurrence is equally common in both sexes and various treatment methods are available to take. Infertility rarely go unnoticed and couples affected more or less. Aim: The aim of the study was to highlight the heterosexual couple's experience of infertility. Method: A literature based study was done through a qualitative approach. The database Cinahl was used in the systematic searches. In total, the study is based on ten qualitative articles and the analysis resulted in three themes with three subthemes each. Results: The couples felt that their relationship was put to the test. They isolated themselves from family and friends because they constantly were reminded of their situation. Seeking support from others with infertility problems on Internet was common. Conclusion: The desire to become a parent was for all couples central but with the diagnosis life couldn’t take the way that was intended. The relationship was affected more or less, and support from various sources and of different types were needed. The importance of the nurse responds couple on a person-centered way highlighted. Person- centered care took advantage of the patient's resources and reduced suffering.

Hagfish are one of the more lucrative commercial opportunities in the world with fisheries harvesting them specifically for food and for their skin for leather-based products. In 2013 a three year experimental fishery opened off the west coast of Vancouver Island, British Columbia in order to determine the sustainability of a Pacific hagfish (Eptatretus stoutii) and Black hagfish (Eptatretus deani) fishery. In this study, I examined the reproductive biology of both species including: length-weight relationships, sex ratios, fecundity, and size-at-gonadal development. This study corroborates previous suggestions that Pacific hagfish are juvenile protogynous hermaphrodites while black hagfish are likely to be dioecious with an unknown juvenile stage. Sexual dimorphism appears in both species of hagfish, which is likely the result of inter- and intraspecific morphological differences. For both species fecundity decreases throughout developmental stages, and the average fecundity is very low (27-32 eggs per female). Additionally, in both species females commence gonadal development prior to males. Furthermore, both species exhibited extreme female: male sex ratios across length-classes, however, in opposite directions. The reproductive biology of Pacific and Black hagfish models that of a k-selected species, which is a species that tends to live long and has a slow growth rate, low fecundity, and late maturity. As a result there are a variety of concerns that should be addressed when developing a sustainable hagfish fishery to prevent collapses observed in previous hagfisheries. / Graduate / 2017-08-23

Student Number : 9703129J - MSc(Med) research report - School of Pathology - Faculty of Health Sciences / Down syndrome is the commonest cause of congenital developmental disability in industrialized countries, where it occurs in approximately 1.4 per 1000 live births. In South Africa, the birth prevalence of Down syndrome was documented as 1.8 and 2.09 per 1000 live births in urban and rural populations, respectively. The physical, psychosocial and emotional burden of Down syndrome on affected families is significant. The aim of this study was to determine the reproductive choices of women with a child with Down syndrome, aged 1 year or older. The survey was conducted using a structured questionnaire. The sample consisted of fifty women; 36 African, 4 Asian and 10 Caucasian. The questionnaire assessed the mothers’ knowledge of Down syndrome prior to diagnosis, what counselling was received and how this knowledge was utilised. Information was also obtained on the mothers’ use of family planning, the knowledge and use of prenatal medical genetic screening and diagnosis, and what decisions would be made in future pregnancies. None of the sample group of mothers had prenatal diagnosis in their pregnancy with their Down syndrome child, but 76% (38) said that they would want prenatal diagnosis in any future pregnancies. Of the 50 mothers, 21 (42%) said they would terminate a pregnancy if Down syndrome had been detected, 26 (52%) said they would not, and 3 (6%) said they were unsure what they would have done if faced with this decision. Of the Caucasian women, 40% (4) said they would opt for termination of pregnancy, 40% (4) said they would not and 20% (2) were unsure. Of the African and Asian women, 52.8% (19) and 75% (3) respectively said they would not terminate an affected fetus. The information from this study can be used to improve the understanding of how women and their families cope with their children with Down syndrome and give insight for the provision of more effective and comprehensive genetic counselling.

The study took as its point of departure the Children’s Act No 38 of 2005 that emanated from the Bill of Rights enshrined in the Constitution of the Republic of South Africa (Act 108 of 1996). This Act has as its primary aims, to promote the preservation and strengthening of families and to give effect to the rights of children as enshrined in the Constitution of the Republic of South Africa, including: protection of children from maltreatment, neglect, abuse or degradation and the fact that the best interest of a child are of paramount importance in every matter concerning children. It was anticipated that the areas of the Children’s Act with its emphasis on the rights of children would empower them in relation to their protection and development in that particular context. When the Act was introduced, it evoked mixed reactions with certain segments of society applauding the government for its efforts, and others condemning the government’s approach towards reproductive health issues affecting children. The primary aim of the research project was to explore the views of a group of parents in the Johannesburg Metro Region 11 regarding reproductive health care as embedded in the Children’s Act. The study took the form of a small-scale, mixed methods, descriptive, cross-sectional survey research design as it sought to elicit participants’ views on those specific clauses in the Act. In addressing the aims and objectives of the study, interview schedules were administered to 35 participants on an individual, face-to-face basis. Participants were adults drawn from Johannesburg Metro Region 11 and the data collected was analysed using descriptive statistics and thematic content analysis. The main findings that emerged from the study were that, participants did not participate in the process leading up to the promulgation of the Children’s Act No 38 of 2005. Consequently, participants had little knowledge about the Act and did not have any knowledge about its objectives. The fact that participants did not support certain clauses has implications for amendment of the Act with reference to the clauses on reproductive health care.