<p>The primary aim of the current study falls within the main framework of the Frontier Program (Pitcher 2005), namely to address aspects of &ldquo / Animal Husbandry&rdquo / . Within this research area, the determination of the effects of handling/grading and chemicals (anaesthetics) on the growth and survivorship of abalone are highlighted as key research areas and these are thus one of the focuses of this research.</p>

In integrated multi-trophic aquaculture (IMTA) production of cultured species may not align temporally. For instance, at an IMTA site in Kyuquot Sound, BC where the cultured species are Anoplopoma fimbria (sablefish), Plactopentin yesoensis (Japanese scallop) and Saccharina latissima (sugar kelp), sablefish are grown year round while the kelp culturing lasts from winter to summer. Kelp sporophytes become visible in early spring while harvest takes place in July. This indicates that at Surprise Island the time period of nutrient extraction by the kelp is limited to only a few months per year. Two potentials methods to lengthen the time in which the kelp component was on site were employed and evaluated: 1. the use of multiple kelp species with potentially differing seasonal growth strategies and; 2. outplanting kelp seed at four different times of the year. The first method involved outplanting seed of four kelp species, Saccharina latissima, Costaria costata, Alaria marginata and Saccharina groenlandica and monitoring growth parameters (blade length and yield). For the second method, a modified seed production method of Merrill and Gillingham (1991) with Luning and Dring (1973) successfully provided seed throughout the year. Seasonally out-planted seed was also monitored for growth parameters. Results were marginal for experiments and were confounded by the lack of growth rates due to infrastructure problems, grazing by naturally setting marine snails and seemingly poor environmental conditions for kelp culturing at the farm site. However, data indicated that certain species in co-culture may slightly increase the time period, and strategically entered kelp seed may do the same. In particular the co-culture of C. costaria and S. groenlandica or biannual seed outplanting in fall and spring may increase the length of growth period of kelp provided certain limitations found during this experiment are overcome (i.e. pressures of grazing). Additional potential benefits with these kelp production strategies are the diversification of final kelp products, additional kelp harvests and increased production. / Graduate

Ulva as an aquaculture crop and IMTA component species has received mixed results globally; success has been achieved in South Africa and Israel, whilst in Europe the results have been poor. This project aims to determine if Ulva lactuca is a suitable candidate as an inorganic extractive species component within marine IMTA systems in British Columbia. The inorganic extractive feasibility of U. lactuca was determined with combination of real time growth and nutrient uptake experiments, alongside a SWOT analysis and literature review to reveal the possible potentialities and pitfalls. U. lactuca was cultivated in 680 litre tanks in the effluent of Wolf Eels, Anarrhichthys ocellatus in a recirculation system at the Aquatics facility at the University of Victoria. Growth experiments of wild local U. lactuca strains attained summer growth of up to 17.43% specific daily growth rate, with winter growth of up to 4.26% specific daily growth rate. U. lactuca demonstrates a preference for Ammonia-N uptake over other forms of inorganic nitrogen and a reduced nutrient uptake capacity during dark periods. Nitrate uptake capacity up to 202µm N gDW-1 day-1 was exhibited. These figures display the excellent biological potential of local Ulva lactuca strains to act as an inorganic extractive. However currently, long term maintenance of the crop proved problematic with instability with growth rates and nutrient uptake capacity. Cultivation issues in combination with poor economic outlook will restrict the feasibility of this species to specific types of IMTA system. Beneficial steps towards the deployment of U. lactuca inorganic extractive components would include: (i) the identification of suitable sterile strains or employment of “germling” spore production, (ii) the use of a rotational, light weight, cage cultivation system, (iii) being farmed in combination with a dark period nutrient removal species, such as Chondrus crispus, (iv) being farmed in conjunction with in-situ algivorous species. / Graduate / 0792

Thesis--Auburn University, 2009. / Abstract. Includes bibliographical references (p. 40-43).

Thesis (Ph. D.)--University of Hawaii at Manoa, 2003. / Includes bibliographical references (leaves 109-118).

Doctorat en Sciences / info:eu-repo/semantics/nonPublished

Magister Scientiae - MSc (Biodiversity and Conservation Biology) / South Africa

Flavobacterium psychrophilum est le pathogène de la maladie de l’eau froide ou du syndromede l’alevin qui provoque des pertes économiques importantes dans les élevages de truite arc-en-cielen Aquitaine. Au cours de cette thèse, nous avons développé dans un premier temps un nouveau testqPCR TaqMan en duplex qui cible les gènes (i) adnr16S de F. psychrophilum et (ii) β-actine de latruite arc-en-ciel ; il permet de déterminer le taux d’infection de tissus contaminés au cours d’unemême analyse.Dans un second temps, nous avons cherché à objectiver trois approches préventives quipourraient être mises en oeuvre pour limiter l’infection à F. psychrophilum dans les élevages. Lacaractérisation de biocides classiquement utilisés par la filière aquacole a permis de proposer auxaquaculteurs des méthodes de désinfection réellement efficaces contre F. psychrophilum mais quin’affectent pas le développement des oeufs ni des futurs alevins. En parallèle, l’impact de la mise enplace de traitement probiotiques a été caractérisé à la surface des oeufs, à la surface du mucus et/oule long du système digestif, dès les tout premiers stades de développement des truites, sur le nombreet l’intensité des crises de flavobactériose dans les élevages. Deux traitements microbiens ont étéretenus : l’E112® (DOXAL-FRANCE, Pessac) et le Bactocell® (LALLEMAND, Toulouse). Enfin, troispréparations vaccinales ont été préparées (« Adjuvant », « Autovaccin » et « Membrane Externe ») ettestées pour leur capacité à protéger les poissons de la flavobactériose. / Flavobacterium psychrophilum is the causative agent of cold water disease or the rainbow troutfry syndrome which causes important economic losses in rainbow trout breedings. During this thesis,we firstly developed a new duplex Taqman qPCR test which targets the following genes (i) F.psychrophilum adnr16S and (ii) rainbow trout β-actine. This test enables to obtain the infection rate ofcontaminated tissues, during a same analysis.Then, we tried to objectivize three preventive approaches which could be implemented inbreedings to limit the infection by F. psychrophilum. The characterization of biocides used inaquaculture allowed proposing to the fish farmers effective methods of disinfection against F.psychrophilum. These methods do not affect the development of eggs or future fish larva. Moreover,the impact of the implementation of probiotics on the surface of eggs, on the surface of the mucusand/or the digestive system, from the very first steps of trout development has been characterized onthe number and the intensity of flavobacteriosis outbreaks in the breeding farms. Two probiotictreatments were selected: l’E112® (DOXAL-FRANCE, Pessac) and Bactocell® (LALLEMAND, Toulouse).Finally, three vaccine preparations (« Adjuvant », « Auto-vaccine » and « Outer Membrane ») wereprepared and tested for their capability to protect farmed fish against flavobacteriosis.

There has been a long history of attempts to promote subsistence rural aquaculture within South Africa. Many of these attempts have failed due to inadequate support from government and support agencies. There has been a recent revived interest in promoting rural aquaculture development. Presented in this project are six scenarios demonstrating the potential application of thermal modelling techniques to improving subsistence rural aquaculture. These scenarios were based on a model validated against a real life system, and run with environmental data for the year 2005. Bovine manure, grass thatch, cereal straw and Typha spp. water reeds were tested for thermal performance. These results were then applied to the scenarios. The open and kraal enclosed pond scenarios yielded the widest deviation in temperatures throughout the year, with an average temperature of 3.8oC and 6.0oC above ambient and a temperature range of 10.6oC and 12.4oC for the year respectively. Eliminating solar radiation and reducing wind speed resulted in an average difference of 1.5oC below ambient and a temperature range of 7.5oC for the year. When completely enclosed in a well-sealed traditional Xhosa style hut, the pond had an average difference of 5.6oC below outside ambient temperature, with a range of 7.8oC for the year. A passive solar heating scenario added to the sealed hut scenario, which when run continuously maintained an average difference of 34.7oC above outside ambient temperatures, with a range of 56oC for the year. When a hypothetical 25oC temperature control was included in the model, the system maintained an average of 7.1oC above ambient outside temperatures, with a temperature range of 0.8oC throughout the year. The wider range of temperatures made available through the use of thermal modelling approaches provides a more diverse range of species available for subsistence rural aquaculture at any site, significantly improving its potential.

I examined the effects of temperature (25, 30, and 35°C) on growth, standard metabolic rate (SMR), and lower dissolved oxygen tolerance (LDOT) of juvenile Speckled Peacock Bass Cichla temensis. Fish were acclimated to 150-L aquaria for 7 weeks before the growth, SMR, and LDOT experiments. The growth study lasted 58 days and fish acclimated to 25 and 30°C displayed similar growth rates, while fish acclimated to 35°C had very poor growth rates. The SMR and LDOT experiments were performed using intermittent respirometers. Fish acclimated to 25°C had the lowest SMR, followed by 30°C, and finally 35°C. The highest LDOT was observed at 25°C, followed by 30°C, and finally 35°C. Collectively, these results suggest that 25-30°C is within the thermal optima of Speckled Peacock Bass for grow-out and survival in an aquaculture setting. Further, I recommend maintaining dissolved oxygen concentrations at or near saturation.