Ten Doeschate, Kim

Includes bibliographical references (leaves 135-154). / The objective of this study was to identify a potential probiotic bacterium that increased the growth and decreased the susceptibility of farmed abalone to pathogenic bacterial infection. The mechanism by which the probiotic is able to increase growth rates and reduced susceptibility to pathogen infection was investigated. A number of bacterial strains were isolated from the digestive tract of Haliotis midae that are capable of degrading a ...

Moonsamy, Karusha

Includes bibliographical references. / Bioluminescence imaging (BLI) is a powerful technique that enables real time monitoring of various processes such as gene regulation, host-pathogen interaction and distribution of bacterial cells in vivo. Most of these processes however have only been monitored in murine models or mammalian tissue culture systems. In order to determine whether BLI could be used to monitor bacterial-host interactions in an invertebrate system, the probiotic bacterium Vibrio ...

Ray, Roslyn Michelle

Includes abstract. / Includes bibliographical references (p. 112-116). / Haliotis midae is an important marine gastropod that is commercially farmed along the South African coastline. The demand for the edible foot of the abalone far exceeds the supply, as such monitoring the health status of commercially farmed abalone is important if the demand is to be met. In farming conditions, bacterial infections can spread rapidly leading to mass mortalities amongst the abalone population. In order for t...

Janse van Rensburg, Marike

Includes abstract. / Includes bibliographical references (leaves 80-89). / Although South Africa is the second largest producer of abalone outside Asia, the sustainability of the industry could be threatened by infectious diseases (Troell et ai., 2006). Probiotics are increasingly being viewed as an alternative to chemical and antibiotic treatments (Balcazar et al., 2006), and have been shown to improve the health of the South African abalone, Haliotis midae (Macey and Coyne, 2005). In order to ...

Makhande, Emmanuel Denis

Haliotis midae is the cornerstone of the South African abalone fishery. For more than a decade, the wild abalone stock of South Africa has suffered decline due to over-exploitation and illegal activities such as poaching. Prior to 1970, no regulations were in place concerning the annual landings. As a result the fishery was exploited as if it were an infinite resource. It is this initial uncontrolled harvesting (regardless of age) and poaching that has driven the abalone resource decline. Due to...

Duncan, Elizabeth A.

<p> Black abalone on California&rsquo;s rocky shores are critically endangered due to overfishing, disease, and increasing environmental temperatures. Risk of thermal stress and disease have been found to increase with variation in body temperature (<i>T</i>_b), yet we lack a clear understanding of the temperature regimes experienced by abalone in the wild. I created a mechanistic heat budget model coupled with long-term meteorological records to identify key environmental controls and...

Francis, Tamson L.

Magister Scientiae - MSc (Biodiversity and Conservation Biology / Beach-cast kelp (the most widely used feed for commercially grown South African abalone) is plentiful during winter months when periodic storms cause kelp to wash ashore. During summer, however, this resource is not always readily available and farmed abalone are often starved for short periods. The aim of this research was to assess how periodic kelp starvation influences growth of the commercially grown abalone, Haliotis midae L...

Knauer, Jens

An adequate supply of diatoms during the weaning stage (generally 5 - 10 mm shell length (SL)) is one of the primary constraints to the commercial culture of the South African abalone, Haliotis midae. Because of the seriousness of the problem, a project aimed at the development of an artificial weaning diet was initiated. Initially, the chemical composition (proximate composition, amino acid, fatty acid and mineral element profile) of juvenile H. midae was analyzed, as a general lack of such inf...

Gray, Michael

In the late 1980's abalone culturalists noticed reduced growth rate and shell deformities in some abalone stocks. These problems were the result of infestations by a shell boring polychaete, Terebrasabella heterouncinata. Under intensive abalone culture conditions the level of infestation can reach epidemic proportions and there are often severe consequences for the host abalone. Heavy sabellid infestation levels have placed the economic viability of several South African farms under threat. Thi...

Ayres, Devin William Philip

Abalone, Haliotis midae, farmers in South Africa that feed formulated diets reported a periodic drop in abalone growth during periods of increased gonad development. A large drop in abalone biomass was noticed after presumed spawning events. This study was aimed to determine the effect of diet and sex-sorting on gonad development in abalone. Experiments were conducted on a commercial abalone farm from July 2012 to the end of June 2013. Isonitrogenous and isoenergetic diets were formulated with t...

Wu, Yu

The inclusion of soya as a dietary protein source in the formulated feed, Abfeed® S34 (Marifeed Pty (Ltd), Hermanus) for farmed abalone, Haliotis midae has resulted in larger gonads during reproductive seasons compared to the gonads of abalone fed kelp or diets that included fishmeal as the only main protein source. The aim of this study was to determine if the isoflavones present in the soya were responsible for this increase in gonad size and the subsequent effects on farmed abalone growth. An...

Naylor, Matthew Aubrey

An understanding of species specific water quality requirements is essential for efficient production of aquaculture products, an aspect not well documented for the land-based culture of the South African abalone, Haliotis midae. In order for the industry to remain competitive in international markets, efficient use of water supplies and the development of water reuse technology is needed. This study assessed the changes in water quality between tanks in a tiered serial-use raceway in relation t...

Yang, Kai-Wen.

Thesis (M.A.)--National Taiwan University Graduate Institute of Zoology. / Includes bibliographical references.

Ainslie, Robert Clark.

Thesis (Ph.D.) -- University of Adelaide, Department of Zoology, 1978.

Shipton, Thomas A.

Thesis (Ph. D.)--Rhodes University, 1999. / "December 1999." Includes bibliographical references.

Clark, Nathaniel L.,

Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (p. 79-94).

Francis, Tamson L.

<p>Beach-cast kelp (the most widely used feed for commercially grown South African abalone) is plentiful during winter months when periodic storms cause kelp to wash ashore. During summer, however, this resource is not always readily available and farmed abalone are often starved for short periods. The aim of this research was to assess how periodic kelp starvation influences growth of the commercially grown abalone, Haliotis midae Linnaeus.</p>

Chang, Seong Ook

The objective of these studies was to develop an analog from surimi that would resemble abalone. Preliminary studies involved the standardization of batter preparation conditions, such as pH adjustment, optimum moisture content and batter mixing time. The texture of a gelled analog prepared with different protein adjuncts egg white, gluten and bovine serum albumin) was compared with cooked abalone for hardness, elasticity, and cohesiveness by a trained sensory evaluation panel and by instrumenta...

Demetropoulos, Carl Lee

Graduation date: 2003

Bryant, Maxine Joyce

Molluscs are biologically important; they form a diverse taxon and the most well known members of the Lophotrochozoa, the most understudied Bilaterian group. Despite this importance, few studies have characterised molluscs at the genetic level. The New Zealand black-footed abalone Haliotis iris, an economically and culturally valued species, was chosen as a model for genetic characterisation of a molluscan actin gene family. In H. iris, actin is essential for the production of a large muscular f...

Griffiths, Allison Muriel

The predation pressures on juvenile Haliotis kamtschatkana, northern abalone, in Barkley Sound. British Columbia, were investigated. Thirty-seven potential predators were tested in the laboratory to determine if they would consume juvenile abalone 1- 25 mm shell length (SL). Six of these potential predators consumed > 10 % of the abalone offered to them and were considered major predators. Natural mortality for juvenile H. kanntschatkana was then estimated by outplanting calcein marked and bee t...

Elias, John Peter

Abstract not available

Khuzwayo, Sharon J.

A gradient of sea temperatures is created along the South African coastline by the confluence of the cold Benguela Current on the West coast with the warm Agulhas Current on the East coast. This temperature gradient allows for an assortment of species to occupy the variety of microenvironments occurring in this area. Amongst these species is commercially important South African abalone, Haliotis midae, which although being capable of existing across this wide range of temperatures grows larger o...

Taylor, Barbara Elan

Development of formulated diets for use in abalone culture demands knowledge of the animal's nutritional requirements, growth, and metabolism. This thesis addresses some important aspects of these issues with regard to the abalone Haliotis kamtschatkana. Protein requirement was investigated from the standpoint of how protein utilization is affected by dietary protein content, amino acid balance, and protein sparing, together with the possible amelioration of the last through enzymatic adapt...

Lambrechts, Daneel

Thesis (MSc)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: The species Haliotis midae is the only abalone species of commercial importance to the South African fisheries industry. The species is currently under substantial pressure due to commercial harvest and illegal poaching, to the extent that genetic and biodiversity may be under threat. The species is also being cultured in commercial systems for supply to international markets. The South African production for 2002 amounted to ...

Nicholson, Gareth Hurst

The profitability of abalone farms is heavily influenced by their production per unit of grow-out space. With farms having physically expanded to the maximum, and with increasing production costs, one of the most realistic ways for farms to increase their production is through optimizing stocking densities. The effect of stocking density on Haliotis midae performance is undocumented and optimal stocking densities for this species have not been determined. Experiments were conducted under farm co...

Greeff, Mariska R.

Magister Scientiae (Biodiversity and Conservation Biology) / Land-based abalone aquaculture in South Africa started in the early 1990s and is based on the local species Haliotis midae. This industry expanded with great success over the last decade. In 2006 abalone exhibiting typical clinical signs of tubercle mycosis was discovered for the first time in South African abalone culture facilities,posing a significant threat to the industry. Halioticida noduliformans, a fungus belonging to the Pero...

by Wong Wai-Yee, Dolly. / Bibliography: leaves 90-102 / Thesis (M.Phil.) -- Chinese University of Hong Kong, 1983

Rhode, Clint

Thesis (PhD)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The South African abalone, Haliotis midae, commonly known as perlemoen, is an economically important gastropod mollusc. Historically, this species maintained a lucrative fisheries sector; however with increasingly lower landings there has now been a shift to aquaculture. Efforts to conserve natural populations and to improve abalone aquaculture production are thus running in parallel. Previous studies reported significant dispariti...

Norval, Alex

Thesis (MBA (Business Management))--Stellenbosch University, 2008. / ENGLISH ABSTRACT: This report begins with a look at the ever increasing world population and the effect this is having on the world's food production. While the demand is increasing with the rise in population, the supply side is finding it difficult to produce enough food due to a number of pressures. The report then goes further by suggesting a source of food that holds great potential for the future which, if it reaches ...

Goosen, Neill Jurgens

ENGLISH ABSTRACT: The first successful captive spawning of the South African abalone Haliotis midae occurred in the 1980’s and subsequently the commercial abalone industry in South Africa has developed, with an estimated investment of US$ 12 million and annual output of 500 to 800 tons by 2001, making South Africa the biggest abalone producer outside of Asia. Natural kelp is currently the major feed and the development of a suitable substitute, and improved disease management in abalone cul...

Teuteberg, B. H.

ENGLISH ABSTRACT: This document details the design process of a 97 kW microhydro system for Roman Bay Sea Farm in Gansbaai in the Western Cape Province of South Africa. It contains a literature study of microhydro power, with a focus on the use of Pump-as-Turbine technology and direct-drive systems. The literature study leads to several possible concepts for the project, which are then evaluated and the most suitable design is found to be a reverse running pump that powers a different pump ...

Gerber, Werner Hugo

Thesis (MSc(Agric))--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: The pnmary alm of this study was to investigate the national competitive advantage of the South African abalone industry. A further aim was therefore to investigate the environment, in which the South-African abalone industry operates. Secondary aims included presenting a detailed description of the roleplayers in the South African abalone industry, and considering whether the South African abalone industry can be m...

Beltran, Caroline Gina Gracieuse

Includes bibliographical references / Haliotis midae is a commercially important abalone in South Africa, previously harvested from a stable, quota-managed fishery. However, the combined effects of overharvesting, increased illegal catches and negative environmental factors led to a collapse in wild populations in the mid-90s. Consequently, land-based aquaculture of H. midae has grown significantly in South Africa, to satisfy the global demand for abalone and alleviate pressure on wild stocks. U...

Ruck, Kevin

Bibliography: leaves 76-87. / Infestations of sabellid polychaetes were found in South African farmed abalone in 1994. Growth experiments confirmed that infested abalone had reduced growth rates. Surveys of both the intertidal and subtidal region at various locations around the South African coastline revealed that the sabellid was endemic to the region. It occurred in a range of mollusc species, but some species were more susceptible than others. The fact that some molluscan species became infe...

Barkai, Revital

Bibliography: pages 65-75. / This study aims to quantify both the individual and population energy budgets of the large edible gastropod Haliotis midae, and is divided into three major sections. Section 1 deals with diet and section 2 the consumption rate, absorption efficiency, respiration rate and rate of ammonia excretion, each of which were measured as functions of wet body mass. Each aspect was studied using animals from two sites subject to different temperature regimes. One of these was o...

Dias, Valera Lucena

Haliotis midae is an economically important South African abalone species which has been cultured since the 1990s. H. midae farming constitutes approximately 93% of the country's total marine aquaculture industry. However, the slow growth rate of this animal and the potential for disease outbreaks remain a concern for farmers. Therefore, government and private institutions have joined efforts to investigate ways of enhancing abalone production, to increase abalone growth rates and improve diseas...

Lloyd, Kyle Everett

Animals generally do not have a requirement for protein, but instead have a requirement for specific essential amino acids (EAAs) and non-essential amino acids (NEAAs). The NEAAs are those that can be synthesised by the animal, however, EAAs cannot be synthesised and must therefore be supplied as part of the diet. When these amino acids (AAs) are supplied in the correct ratios and with the correct level of digestible energy, nutritionists can maximise somatic growth from proteins. This has resul...

Calder, Bridget

Includes bibliographical references. / The abalone Haliotis midae has been fished to near-extinction on the South African coastline, primarily to satisfy a growing international market. In order to meet demands, H. midae has been produced in South Africa by aquaculture for several decades, and the South African abalone aquaculture industry continues to expand. Internationally, abalone aquaculture has been actively affected by the outbreak of bacterial and viral diseases, which spread rapidly and...

Witte, Andrew Dennis

Marine ranching has been identified as an alternative to traditional aquacultural rearing and growing organisms for consumption. In the Eastern Cape, abalone ranching is a new and experimental industry. The aims of the research were to: first develop a GIS model to assist management in site selection for abalone seeding; and secondly to develop and standardize the sampling methodology in order to ground truth the sites, and assist in the monitoring and habitat identification of abalone. The GIS ...

Lyons, Jarrod

Identifying genes which are up-regulated in response to stress has become important in understanding invertebrate immunity. The HSP70 gene from Haliotis midae was successfuly cloned and sequenced, and was found to have highest similarity (99%) with Haliotis diversicolor.

Van Wyk, Jennifer Caroline

Includes bibliographical references. / Farmed abalone is a reliable and good quality source of abalone. Cryptococcus species SS1 was isolated from the gut of the South African abalone, Haliotis midae, and has been identified as a potential probiotic for farmed abalone. The implementation of strain SS1 as a probiotic for aquacultured abalone required the design of a fermentation system to produce hjgh concentrations of the yeast strain in order to supply the probiotic to commercial abalone produc...

Nini, Nobuhle Aurelia

Abalone poaching is a major problem in South Africa. The South African abalone, Haliotis midae, rates as an extreme example of high levels of illegal harvesting. The research aimed at examining the role of the different role players in preventing poaching of the species in the East London area of the Eastern Cape Province of South Africa and determining the challenges the officers faced as there was an increase in poaching in the area. To achieve this aim, the research techniques including quest...

Green, Alistair John

The abalone (Haliotis midae) culture industry in South Africa is becoming increasingly dependent on the use of formulated feeds, due to limitations in the supply of kelp. The bulk of the feeds that are currently available were developed based on the requirements of juvenile abalone cultured within the optimal temperature range for growth (18 - 20 °C). However, most abalone farming facilities are land-based pump ashore operations and are thus mostly exposed to temperatures outside of this range. ...

Simon, Carol Anne

Terebrasabella heterouncinata is a small K-selected sabellid polychaete. It is a simultaneous hermaphrodite with a semi-continuous mode of reproduction, producing relatively few large eggs that are brooded within the parental burrow until the larvae emerge, to settle on the growing edge of the abalone shell. Despite its low fecundity, this worm has become problematic on abalone farms in South Africa. The present study was conducted to gain an understanding of the life history patterns of T. hele...

Riddin, Nicholas Alwyn

According to farm records, cultured Haliotis midae (50-70 g.abalone⁻¹) were growing 10% slower in winter when compared to summer. This reduction in growth rate also coincided with enlarged gonads. Initial trials showed that there were differences in mean monthly growth rates ranging from 1.97 – 5.14 g abalone⁻¹ month⁻¹, and gonad bulk index (GBI) also varied between months (GBI range: 26.88 ± 12.87 to 51.03 ± 34.47). The investment of energy into gonad tissue growth did not compromise whole body...

Sales, James

The evaluation of potential alternative protein sources for the formulation of least-cost optimal diets to satisfy the nutrient requirements of South African abalone (Haliotis midae) has been hampered by the absence of a suitable, practical, replicable and reliable digestibility technique. A suitable lowcost faeces collection technique was developed in this study to obtain suitable quantities of excreta for analysis from this species. Acid-insoluble ash was identified as a reliable, replicable a...

Dixon, Mark Geoffrey

Inadequate information of the nutritive physiology and the dietary requirements of abalone are the principle factors that currently limit the development of a formulated feed for the commercial culture of Haliotis midae. The need to develop a method to determine apparent digestibility co-efficient's for abalone in order to facilitate further applied nutritional research was identified. Animals between 50 and 80 mm were collected from natural stocks along the east Cape coast of South Africa at Po...

Maliza, Siyabonga

Physiological stress in farmed abalone can lead to immunosuppression and increase the susceptibility to bacterial, viral and parasitic disease, often followed by mortality. Thus, handling and poor water quality can reduce farm production efficiency. Probiotics in aquaculture have been effective in a wide range of species in enhancing immunity, survival, improving feed utilisation and growth. Three putative probionts identified as a result of in vitro screening had been beneficial to laboratory-r...

Kemp, Robert Charles

"November 2001" / Bibliography: leaves 162-184. / xxi, 184 leaves : ill., plates ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Science, 2005