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Showing 1 to 20 of 49 for “"Ulva"”.
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An investigation of protein variation in Ulva lactuca and Ulva rigida under high nitrogen culture conditions
… of two macroalgae under culture conditions. Ulva lactuca and U rigida were grown in saturating NH₄⁺ - N (1 mM) and PO₄³⁻P (70 μM ) concentrations. Of the two, protein levels of U. lactuca showed the greatest increase over time. Natural populations had a content of 3.7 % of dry weight. This …
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Microbiome associated with Ulva lacinulata and seawater in an integrated abalone (Haliotis midae)–Ulva system with partial recirculation
… commercial abalone farms in South Africa grow Ulva in D-ended raceways to bioremediate farm effluent water, allowing water to be recirculated back to the abalone, while Ulva is often used as a supplementary feed source. Despite Ulva's versatility in integrated multi-trophic aquaculture (IMTA) …
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Ecophysiological studies of three South African Ulva species from integrated seaweed
In South Africa, Ulva cultivation is of paramount importance to the marine aquaculture industry. Three local Ulva species (Ulva lactuca Linnaeus, Ulva rigida C. Agardh and Ulva capensis Areschoug) were selected for this research. The first two are currently cultivated on abalone farms for abalone …
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Ulva as a functional feed: a practical investigation into the effects of Ulva lacinulata on the growth, consumption, health and gut microbiota of the farmed abalone Haliotis midae
… adoption of cultivation of the macroalga Ulva by the South African abalone aquaculture industry using IMTA systems. Farms that use fresh Ulva as a supplement to formulated feed have reported a reduction in the volume of formulated feed required to achieve optimal growth of abalone however, …
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Chemosensory properties of different Ulva extracts and their effects on Tripneustes gratilla
… Tripneustes gratilla for four crude extracts of Ulva as well as Fresh Ulva and an artificial feed. The four crude extracts of Ulva (Methanolic, Ethanolic, Chloroform and Chloroform-Methanol extracts) were tested by pair-wise chemosensory trials in a Y shaped maze. Urchins were significantly …
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Feed attractants in aquaculture - the chemical composition of aquacultured Ulva lacinulata (Chlorophyta)
… two decades, cultivation of the green seaweed Ulva lacinulata (Ulvales) has proven to be commercially viable and an integral part of the South African abalone aquaculture industry. This seaweed is not sold, but mainly used as feed for the abalone Haliotis midae (Lepetellida) and on some farms …
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Taxonomy of Ulva species (Chlorophyta) in the South Western Cape, South Africa
Six species of Ulva, U. atroviridis Levring, U. capensis Areschoug, U. fasciata Delile, U. lactuca L., U. rigida C.Agardh and U. uncialis Kutzing, have been reported to occur in the south western Cape Province. As a result of herbarium, field and culture studies it was found that five of these …
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Microorganisms associated with ulva grown in abalone effluent water: implications for biosecurity
Macroalgae such as Ulva are living hosts that are known to perform essential roles in marine ecosystems, and are extensively utilised for several aquaculture operations, including in the integrated production of high value goods such as abalone. Intensive aquaculture operations along the coastline …
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Variation in chemical components of aquacultured Ulva (Chlorophyta) in response to environmental variables
A detailed literature review of relevant Ulva biology and chemical composition is included. Marine algae are known to produce a wide range of volatile organic compounds that are primarily used in chemical communications. These compounds are released in seawater and act as either pheromones or …
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Estudio y evaluación del potencial alimentario del alga verde Ulva spp. de los esteros gaditanos
… en la Bahía de Cádiz, se desarrollan algas como Ulva spp. en lugares como los esteros, zonas pertenecientes a antiguas salinas y, por tanto, con características ambientales particulares condicionadas por el sistema de producción de sal. En la presente Tesis Doctoral se propone la recolección y …
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The use of ULVA as a feed supplement in the development of an artificial diet and feeding regimes to produce export quality roe from the sea urchin Tripneustes gratilla (Linnaeus)
… aim of this research was to determine whether Ulva supplementation would improve palatability, consumption and digestibility of an artificial feed administered to T. gratilla and optimise gonad production and quality. At an inclusion level of 20% (20U), Ulva was shown to significantly (p < …
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Characterization of Ulva (Ulvaceae, Chlorophyta) species cultured in commercial abalone farms in South Africa, and comparison with closely related wild species, using morpho-anatomical and molecular methods
… of species cultured in South Africa, with Ulva species cultured at a commercial scale. In South Africa, the annual production of Ulva is approximately 2000 tonnes (wet weight), with the majority of Ulva being grown in landbased paddle raceway systems receiving abalone effluent water. …
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Biological and economical feasibility studies of using seaweeds Ulva lactuca (Chlorophyta) in recirculation systems in abalone farming
… integrated aquaculture system using Ulva lactuca was feasible as well as to test the differences between a commercial gravel bed recirculation system to an existing flow through system. These studies were carried out at two abalone farms: Danger Point (I & J) (140 km east of Cape …
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The feasibility of a commercial-scale recirculating aquaculture system integrating sea urchins (Tripneustes gratilla) and seaweed (Ulva)
… Tripneustes gratilla, and the green macroalga, Ulva, could be suitable co-candidates for a land-based recirculating Integrated MultiTrophic Aquaculture (IMTA) system. This IMTA system is suggested to be sustainable and efficient, primarily because the Ulva would simultaneously provide …
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Attractant properties of chemical constituents of the green macroalga Ulva and their response effects on the commercially important sea urchin Tripneustes gratilla
… has a significant preference for the macroalgae Ulva. The purpose of this study is to assess what chemicals contained in Ulva cause this preference. Chemosensory trials involving Ulva and its chemical constituents, as well as wounded Ulva and an artificial feed, were carried out using a Y-shaped …
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The molecular systematics of Ulva Linnaeus and Enteromorpha Link (Ulvales, Chlorophyta) from the South Western Cape, South Africa
Both Ulva and Enteromorpha are very common, ubiquitous, and environmentally important genera of green seaweeds. The evolutionary history of Ulva species is poorly understood, stemming from a lack of diagnostic, non-molecular systematic characters. This study addresses the following questions: i) Do …
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Determining larval settlement, post-settlement and weaning substrates and regimes for the sea urchin Tripneustes gratilla in intensive aquaculture
… and the timing of weaning onto macroalgae (Ulva lacinulata). Experimental substrates tested include: Ulvella lens, fresh Ulva, dried Ulva and alginate, dried Ulva and agar, Nitzschia sp. (undescribed diatom), dried Isochrysis galbana and alginate, probiotic Vibrio midae SY9 and alginate, V. …
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Fauna de Gammaridea (Crustacea-Amphipoda) associada a ulva em trechos de litoral escarpado de Niterói e Angra dos Reis - RJ
… Brazil). The samples were collected only in ulva Which were dug up from the upper mediolitoral of points of collections of Baia Guanabara (Niterói), Atlantic litoral (Niterói) and Baia de Ilha Grande (Angra dos Reis).The fauna studied, about 1500 specimens, underwent fixing techniques, …
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