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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The transport of avian sperm cells in the femal reproduction tract.

Degen, Allan Abraham. January 1971 (has links)
No description available.
2

The effect of coloured lights on the reproduction of Wistar rats

Aldous, John Gray January 1941 (has links)
[No abstract submitted] / Science, Faculty of / Botany, Department of / Zoology, Department of / Graduate
3

The transport of avian sperm cells in the femal reproduction tract.

Degen, Allan Abraham. January 1971 (has links)
No description available.
4

Facultative sex model /

Cheung, Kai Chung. January 2008 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2008. / Includes bibliographical references (p. 43-44).
5

The reproductive biology of two commercially important species of threadfin bream, Nemipterus virgatus and N. japonicus

劉柏輝, Lau, Pak-fai. January 1999 (has links)
published_or_final_version / Ecology and Biodiversity / Master / Master of Philosophy
6

Aspects of reproduction in the leaf-foldind frog afrixalus delicatus

Backwell, Patricia Ruth Yvonne 06 June 2016 (has links)
Thesis submitted to the Faculty ofScience, University of the Witwatersrand, Johannesburg in fulfilment of the requirements for the degree Gf'Doctol' ofPhilosophy, (! JOHANNESBURG January 1991 / This work examines aspects of sexual reproduction in the previously littlestudied Leaf-foldillg Frog, A£rixalus dellcatus, The taxonomic status of this species was determined using the Mate Recognition System to deUmJt the species boundary. Male social behaviour was investigated with particular reference to. the structure and functional partitioning of the twopart advertisement call; the maintenance of intermale spacing and the effects of chorus size on the sp'atial separation of males; chorus organisation; call site selecticn and fidelity to. call sites. The climatic factors influencing male behaviour were also examined. The mating success of calling and satellite males was determined and the possible causes of the variation in mating success were examined. Female behavioul' was also extensively studied, Females were found to produce a .$xnall numbel' of large eggs tI1at are protected in leaf nests. Oviposition site rf¥tq~em;(;;lntswere detertnined, and the concentration of nests examined. "~~l~a1ti;ll>ll ·Sl'P!OO'$$$ Wlll;S fou'DiGi'tobe lligh. Some females were found to be llol~atl:d~(;)llS, ma:~r:tfgwit~ up to three nl,ales. The behaviour of females in the 'cl.mQ~t:tsW~ observed andfemales were round to generally mate with one of the nearw ma1$s irrespective of morphology or behaviour. The potential and actual a,,(lcutacyormata loc.alisation was determined. This study of a species' mating system and its flexibility in relation to eeclogleal, ph1~o.1~~td and social pressures' allowed for a more thorough understanding oi anlllrtUl.rep:tod~etive behavlour and its evtiiution.
7

Breeding systems and pistil structure in the family proteaceae / Merran Lisa Matthews.

Matthews, Merran Lisa January 1998 (has links)
Bibliography: leaves 173-184. / xiv, 188, [7] leaves, [58] leaves of plates : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This study aimed to broaden understanding of breeding systems in Australian Proteaceae and to study the optimum requirements for promotion of seed germination in two lesser researched genera with horticultural potential, Dryandra quercifolia and Dryandra formosa. The timing and pattern of stigma receptivity was determined using a combination of techniques. Findings can be used to breed and improve these species for further commercialisation in cut flower and garden industries. The study of pistil structure further identified the potential of this structure to affect the capacity of a proteaceous flower to be fertilised. Aspects such as the morphology and size of the stigmatic cavity and the quantity of transmitting tissue in the style were highlighted as filters to pollen tube passage. Comparative studies with other angiosperm species confirmed the unusual structure of the pistil of the proteaceous flower. Seed germination was found to be promoted by exposure of seeds to controlled temperatures of 15C. / Thesis (Ph.D.)--University of Adelaide, Dept. of Horticulture, Viticulture and Oenology, 1998
8

Breeding systems and pistil structure in the family proteaceae

Matthews, Merran Lisa. January 1998 (has links) (PDF)
Bibliography: leaves 173-184. This study aimed to broaden understanding of breeding systems in Australian Proteaceae and to study the optimum requirements for promotion of seed germination in two lesser researched genera with horticultural potential, Dryandra quercifolia and Dryandra formosa. The timing and pattern of stigma receptivity was determined using a combination of techniques. Findings can be used to breed and improve these species for further commercialisation in cut flower and garden industries. The study of pistil structure further identified the potential of this structure to affect the capacity of a proteaceous flower to be fertilised. Aspects such as the morphology and size of the stigmatic cavity and the quantity of transmitting tissue in the style were highlighted as filters to pollen tube passage. Comparative studies with other angiosperm species confirmed the unusual structure of the pistil of the proteaceous flower. Seed germination was found to be promoted by exposure of seeds to controlled temperatures of 15°C.
9

Maturation in vitro and subsequent fertilization of mammalian follicular oocytes.

Shea, Brian Francis. January 1974 (has links)
No description available.
10

Reproductive strategies of males in the egg parasitoid Trichogramma turkestanica Meyer (Hymenoptera:Trichogrammatidae)

Martel, Véronique. January 2007 (has links)
In most animals, males are assumed to have access to an unlimited supply of sperm, while females produce few eggs that are large and costly to produce. In parasitoids, there is a paradigm to the effect that males are polyandrous, inseminate as many females as possible and express no optimization in their behaviours. In reality, sperm production incurs non-trivial costs. Because sperm are transferred in ejaculates and that their cost is greater than that of individual sperm, males can gain by carefully allocating their ejaculates. In this thesis I have investigated different aspects of males' reproductive strategies, mainly sperm and time allocation, in the egg parasitoid Trichogramma turkestanica Meyer (Hymenoptera: Trichogrammatidae). / In T. turkestanica, mating mainly occur on the emergence patch. However, results show that mating opportunities are not distributed equally among males and 2.9% of successful males are sperm-depleted when they disperse from the emergence patch. Nevertheless, 97.1% of males disperse non sperm-depleted, suggesting off-patch mating potential. Male T. turkestanica have thus an insemination capacity higher than necessary to inseminate the females present on the emergence patch, a pattern that seems to be common among parasitic wasps. / On the emergence patch, both virgin and mated females can be encountered. Males are able to discriminate between those mates and prefer virgin ones. This preference is stronger for energy- and time-limited males. / Sperm competition risks and/or intensity are important for males that decrease their sperm investment when the number of rivals increases. Such response is optimal when the benefits from investing more sperm become lower than the costs of a low paternity assurance under intense sperm competition. / Finally, male T. turkestanica express behaviours enabling them to optimize their patch time exploitation. Depending on their evaluation of the patch quality, males modify their patch residence time. / This thesis shows that time- and sperm-limited male T. turkestanica are not simply maximizing the number of females inseminated, but rather maximize their lifetime fitness by optimizing sperm and patch time allocation.

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