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Palynological Investigations Of Cenomanian Chalks And Marls From England, Ailbhe Maire Duane Jan 1992

Palynological Investigations Of Cenomanian Chalks And Marls From England, Ailbhe Maire Duane

School of Geography, Earth and Environmental Sciences Theses

The palynological analysis of chalk and marl samples from Cenomanian sections sampled at high resolution has yielded largely diverse and abundant, well-preserved microplankton assemblages. Four sections have been investigated, three from the Dover-Folkestone Warren area, south-east England and the fourth from South Ferriby, South Humberside, north-east England. The dinoflagellate cysts present accord well with previously described Cenomanian microplankton assemblages from western Europe, and are assignable to the established Litosphaeridium siphonophorum Zone of Davey (1970). Full descriptions of all dinoflagellate cyst species found have been included. A new species, Litosphaeridium sp. A is believed to be indicative of latest Cenomanian to …

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Classification Of Complex Two-Dimensional Images In A Parallel Distributed Processing Architecture, Robert Gilmour Simpson Jan 1992

Classification Of Complex Two-Dimensional Images In A Parallel Distributed Processing Architecture, Robert Gilmour Simpson

Other Faculty of Science and Engineering Theses

Neural network analysis is proposed and evaluated as a method of analysis of marine biological data, specifically images of plankton specimens. The quantification of the various plankton species is of great scientific importance, from modelling global climatic change to predicting the economic effects of toxic red tides. A preliminary evaluation of the neural network technique is made by the development of a back-propagation system that successfully learns to distinguish between two co-occurring morphologically similar species from the North Atlantic Ocean, namely Ceratium arcticum and C. longipes. Various techniques are developed to handle the indeterminately labelled source data, pre-process the images …

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Mediterranean Lens After Collision With Seamounts, Gi Shapiro, Sl Meschanov, Mv Yemel’Yanov Jan 1992

Mediterranean Lens After Collision With Seamounts, Gi Shapiro, Sl Meschanov, Mv Yemel’Yanov

School of Biological and Marine Sciences

No abstract provided.

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The Enteric Delivery Of Macromolecules And Subsequent Immune Response In The Cichlid Oreochromis Mossambicus, Paul Jenkins Jan 1992

The Enteric Delivery Of Macromolecules And Subsequent Immune Response In The Cichlid Oreochromis Mossambicus, Paul Jenkins

School of Biological and Marine Sciences Theses

Enhanced enteric delivery systems were examined in the cichlid Oreochromis mossambicus to evaluate the requirements for potential oral vaccination strategies in teleost fish. Human gamma globulin (HGG) was delivered enterically (orally or anally) to the intestine of O.mossambicus as a standard test antigen. The co-administration of the saponin Quillaja saponaria (Quil-A) was evaluated as a novel oral adjuvant, delivered with the antigen in a soluble form and also as a delivery vehicle in the form of micelles and immunestimulatory complexes (ISCOMS). HGG absorption across the intestine was monitored utilising sensitive immunocytochemical techniques which showed that the enterically delivered antigen was …

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Cryptocaryon Irritans Brown, 1951 (Ciliophora): Transmission And Immune Response In The Mullet Chelon Labrosus (Risso, 1826), Peter John Burgess Jan 1992

Cryptocaryon Irritans Brown, 1951 (Ciliophora): Transmission And Immune Response In The Mullet Chelon Labrosus (Risso, 1826), Peter John Burgess

School of Biological and Marine Sciences Theses

A standardised procedure was established for the laboratory maintenance of C.irritans in thick-lipped mullet. Nine isolates of C.irritans were obtained of which eight were successfully established for up to 48 weeks. Studies on individual life cycle stages with regards to longevity, viability, and susceptibility to a chemotherapeutic agent, revealed the difficulties in eradicating the cysts. Transmission of the parasite both to and from the host correlated with darkness. High infection levels resulted in the death of host fish within five days following exposure to theronts. An acquired protective immune response developed in host mullet within 14 days after exposure to …

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The Birth And Evolution Of Intense Dipolar Eddies, Vn Konshin, S G.I. Jan 1992

The Birth And Evolution Of Intense Dipolar Eddies, Vn Konshin, S G.I.

School of Biological and Marine Sciences

No abstract provided.

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Epidemiological Studies Of The Bacterial Fish Pathogen Yersinia Ruckeri, Christopher John Rodgers Jan 1991

Epidemiological Studies Of The Bacterial Fish Pathogen Yersinia Ruckeri, Christopher John Rodgers

School of Biological and Marine Sciences Theses

A new mediumi, designated Ribose Ornithine Deoxycholate agar (ROD), was developed and used in field trials at two fish farms where fish were known to have ERM. The medium indicated that Yersinia ruckeri could occur in faeces four to six weeks before appearing in the kidney. Fxurther epidemiological studies dealing with fish condition, performance, disease signs and water isolation are presented. These factors are discussed in relation to husbandry and management practices. The minimum uihibitory concentration (MIC) values for 124 strains of F. ruckeri were detemuned. The effect of oxolinic acid, oxytetracycline and a potentiated sulphonamide, on growth patterns over …

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Rapid Cryogenic Fixation Of Biological Specimens For Electron Microscopy, Keith Patrick Ryan Jan 1991

Rapid Cryogenic Fixation Of Biological Specimens For Electron Microscopy, Keith Patrick Ryan

School of Biological and Marine Sciences Theses

This thesis describes investigations into cryofixation by the plunge-cooling technique, at ambient pressure. The objective was to characterise coolants which are commonly used for cryofixation, so that the structure and chemistry of biological specimens may be preserved in a more life-like state. The work began with the design of a suitable cooling device. This was developed further into a large test-bed apparatus which was used in both biological and methodological experiments. The large cooling apparatus demonstrated for the first time that ethane was a superior coolant under forced convection, compared to propane or Freon 22, for bare thermocouples, for exposed …

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Ground Flora And Seed Banks Of Woodlands In South West England, Susan Jane Warr Jan 1991

Ground Flora And Seed Banks Of Woodlands In South West England, Susan Jane Warr

School of Biological and Marine Sciences Theses

This thesis examines the ground flora and seed banks of a range of forest and woodland types in south west England. Ground flora surveys were earned out and seed banks investigated by sampling and germination trials. Depletion of both the ground flora and seed banks of conifer plantations and neglected coppice was shown to have occurred after periods of 40-50 years or more. Re-coppicing or clear-felling of such woodlands did not always result in immediate ground flora recovery and subsequent seed bank renewal. After long periods of shade, resulting from neglect or the presence of a dense conifer canopy, the …

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On-Line Analyte Preconcentration With Atomic Spectrometric Detection., L. Ebdon, A. S. Fisher, S. J. Hill, P. J. Worsfold Jan 1991

On-Line Analyte Preconcentration With Atomic Spectrometric Detection., L. Ebdon, A. S. Fisher, S. J. Hill, P. J. Worsfold

School of Geography, Earth and Environmental Sciences

Pre-concentration of analytes, or matrix removal to overcome interferences using mini- or micro-columns of exchange media prior to atomic spectrometric detection is becoming increasingly more common. This paper is a review of some of the more recent applications of chelating, ion exchange and other resins and gels that have been used to accomplish this.

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Estuaries As Sources Of Methylated Arsenic To The North Sea, Heather Jane Kitts Jan 1991

Estuaries As Sources Of Methylated Arsenic To The North Sea, Heather Jane Kitts

School of Geography, Earth and Environmental Sciences Theses

Analytical techniques were developed for the detection of inorganic arsenic (As(III) and As(V)), monomethylarsenic (MMA) and dimethylarsenic (DMA) in water, pore waters, suspended particles and bed sediments of the Humber Estuary, Thames Estuary and the southern North Sea. Dissolved inorganic As in the Humber Estuary showed removal in the mouth of the estuary in association with an Fe-rich outfall. Intertidal sediments and suspended particles had elevated inorganic As concentrations in the vicinity of the As-rich outfall located in the low salinity zone. Particulate As had a distinct concentration gradient away from the estuary mouth, indicating the transport of As out …

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Studies Of Sediments In A Tidal Environment, Fiona Fitzpatrick Jan 1991

Studies Of Sediments In A Tidal Environment, Fiona Fitzpatrick

School of Geography, Earth and Environmental Sciences Theses

Five sedimentary environments in Plymouth Sound, S.W. England, are defined by side-scan sonar surveys calibrated by direct sampling by SCUBA divers: (i) uniform mud depocentres, (ii) areas of continual sediment reworking, (iii) areas of relict sedimentation, (iv) areas of episodic deposition and, (v) clean-washed rock outcrops. Net sediment transport paths are defined using the physical properties of the sediment. Analysis of Airborne Thematic Mapper and Compact Airborne Spectographic Imager scanner data at High and Low Water, with concurrent sampling has enabled the relationship to be established between suspended sediment concentration, percentage organics, temperature and salinity and a marked continuity between …

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The Near-Miss Experience: Organization Change In The Maritime Bridge-Watch, Doward G. Douwsma Jan 1991

The Near-Miss Experience: Organization Change In The Maritime Bridge-Watch, Doward G. Douwsma

Other Faculty of Science and Engineering Theses

This thesis describes twenty-seven near-miss experiences by ten merchant marine officers on the U.S. Great Lakes. The experiences are related in the first person and include actions by self, other bridge watch members, and other vessels. The focus of the work is on the relationship between the near-miss experience and the organizational implications related to those experiences. The survey of the literature defines the near-miss experience and two major previous efforts to obtain and record maritime near-misses. The conceptual context places the near-miss in the traditional maritime organization which is defined through analysis of boundary and environment, horizontal and vertical …

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Observations Of Estuarine Turbulence And Floc Size Variations, Jeremy Charles Mccabe Jan 1991

Observations Of Estuarine Turbulence And Floc Size Variations, Jeremy Charles Mccabe

Other Faculty of Science and Engineering Theses

Laboratory studies show that turbulence controls the size of flocs by disrupting those flocs which exceed a critical diameter. Estuarine floc sizes have been shown to vary with the spring/neap cycle and turbulence has been suggested as the mechanism. A survey of the tidal variations of cohesive sediment floc size distributions and turbulence parameters has been undertaken in the Tamar estuary in south-west Britain. In-situ particle size distributions have been obtained using a 'marinised' version of the 'Malvern' laser diffraction sizing system. Turbulent current speeds were obtained using 10 cm diameter annular electromagnetic current meters. Velocity data is analysed using …

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Development And Evaluation Of A New Scale To Measure Motivation, Clive Thacker Jan 1991

Development And Evaluation Of A New Scale To Measure Motivation, Clive Thacker

School of Psychology Theses

This programme of research was undertaken with the aim of using psychometric techniques to develop and evaluate a new scale to measure motivation. An initial hypothesis was stated, proposing that five related factors could be used to describe individual differences in certain motivational determinants. These factors are Goal Coherence, Strength of Will, Planning, Perseverance, and Self Evaluation. A questionnaire was constructed, and versions administered to 813 subjects over 5 studies. The resultant data were subjected to maximum likelihood factoring, and the solutions rotated obliquely. Results from each study led to successive refinements of the questionnaire, and an eventual rejection of …

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Evaluation Of Animal And Plant By-Products As Constituents In Diets For Seabream Sparus Aurata L., Ioannis Nengas Jan 1991

Evaluation Of Animal And Plant By-Products As Constituents In Diets For Seabream Sparus Aurata L., Ioannis Nengas

School of Biological and Marine Sciences Theses

The principle aim of the study was to evaluate the nutritional value of animal and plant by-products, with the objective of improving the cost effectiveness of diets for culturing seabream (Sparus aurata). The programme of work was initially directed towards applying the current methodology used in fish nutrition research to establish reliable digestibility coefficients for various feed ingredients. A selection of animal and plant materials were tested for digestibility within a reference basal diet designed for seabream. Ingredients for special consideration included poultry by-product meal, feather meal, meat and bone meal, solvent extracted and full fat soyabean meal as well …

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Evaluation Of Microbial Extracts For Contamination Control In Plant Tissue Culture Systems, Shayne Hussain Jan 1991

Evaluation Of Microbial Extracts For Contamination Control In Plant Tissue Culture Systems, Shayne Hussain

School of Biological and Marine Sciences Theses

Culture filtrates of 13 microbial antagonists exhibited in vitro growth inhibition of a range of test contaminations of herbaceous and woody plant tissue culture systems. Filtrates produced by Bacillus subtilis and Trichoderma viride isolates displayed the greatest broad- range inhibitory activity. Microscopic analysis of antagonized fungal mycelia revealed altered hyphal morphology. Maximum filtrate inhibitory activity was produced when selected antagonists were cultured within a pH range of 5-7 and a temperature range of 20-35°C. Filtrates were thermo-stable at 70°C and could be stored for up to 4 weeks with only a minimal reduction in their inhibitory activity. Bulk-volume production of …

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On-Line Analyte Preconcentration With Atomic Spectrometric Detection, L Ebdon, As Fisher, Sj Hill, Pj Worsfold Jan 1991

On-Line Analyte Preconcentration With Atomic Spectrometric Detection, L Ebdon, As Fisher, Sj Hill, Pj Worsfold

School of Geography, Earth and Environmental Sciences

Pre-concentration of analytes, or matrix removal to overcome interferences using mini- or micro-columns of exchange media prior to atomic spectrometric detection is becoming increasingly more common. This paper is a review of some of the more recent applications of chelating, ion exchange and other resins and gels that have been used to accomplish this.

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The Trophic Level Of Mytilicola Intestinalis Steuer (Copepoda: Poecilostomatoida) In Mytilus Edulis L., As Determined From Stable Isotope Analysis, K Gresty, C Quarmby Jan 1991

The Trophic Level Of Mytilicola Intestinalis Steuer (Copepoda: Poecilostomatoida) In Mytilus Edulis L., As Determined From Stable Isotope Analysis, K Gresty, C Quarmby

School of Biological and Marine Sciences

Mytilicola intestinalis inhabits the digestive tract of the commercially important European blue mussel Mytilus edulis. Early researchers believed that Mytilicola damaged the host by feeding directly upon the epithelial lining of the host intestine, whilst more recent work indicated that it does not seriously affect the host and feeds upon excess food (phytoplankton and detritus) which passes through the mussel intestine. Comparative analysis of the stable isotope 15N shows that it is 2.8 ppt higher in whole Mytilicola than in mussel intestine, suggesting that Mytilicola occupies a higher a trophic level than Mytilus and therefore is unlikely to use the …

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Mesoscale Structure Of Temperature And Salinity In Southern Part Of The Scotia Sea, M.V. Emelianov, G.I. Shapiro Jan 1991

Mesoscale Structure Of Temperature And Salinity In Southern Part Of The Scotia Sea, M.V. Emelianov, G.I. Shapiro

School of Biological and Marine Sciences

No abstract provided.

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Factors Affecting The Pathogenicity Of Yersinia Ruckeri, Maria Dolores Furones Nozal Jan 1990

Factors Affecting The Pathogenicity Of Yersinia Ruckeri, Maria Dolores Furones Nozal

School of Biological and Marine Sciences Theses

A group of 42 strains of Yersinia ruckeri were characterized and found to show homogenous biochemical profiles. The optimal conditions for in vitro culture of a representative strain of Y. ruckeri were established. The virulence was increased by passage through fish. A standard method for infection of rainbow trout (Oncorhynchus mykiss) with Y. ruckeri was devised. As a result cultures of Y. ruckeri grown on full strength of BHIA for 5 h at 30°C in static conditions were found to be most suitable for infection by both intraperitoneal injection and immersion. Virulence of stored cultures was maintained for over 1 …

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The Immune Responses Of Carp, Cyprinus Carpio L., Following Direct Immersion Immunization, Alan Foster Bridges Jan 1990

The Immune Responses Of Carp, Cyprinus Carpio L., Following Direct Immersion Immunization, Alan Foster Bridges

School of Biological and Marine Sciences Theses

The investigations presented in this thesis include studies on a) the immune responses of carp following direct immersion immunization and subsequent intraperitoneal (i.p.) challenge, b) the uptake and accumulation in carp of a direct immersion vaccine and c) phagocytic uptake by carp peritoneal exudate cells (PECs). To assess the cell-mediated immune response of carp, a micro chemotaxis technique was developed, measuring the production of chemotactic factor-like activity in supernatants from incubations of pronephric cells with antigen. In no case were serum antibody titres or a cell-mediated immune response detectable after immersions alone in antigen. It was found that an i.p. …

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Arsenic Speciation In Food, Simon Branch Jan 1990

Arsenic Speciation In Food, Simon Branch

School of Geography, Earth and Environmental Sciences Theses

A high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) method has been developed for the separation and quantification of ~g kg-1 levels of arsenobetaine, monomethylarsonic acid (MMAA), dimethylarsinic acid (DMAA) , arsenite and arsenate. Using this coupling, arsenic species in fruit and vegetables grown on soils containing up to 1.4% w\w arsenic have been surveyed and DMAA, MMAA, arsenite and arsenate identified in the plants. Although extraction efficiencies were poor, typically 10%, total arsenic determinations demonstrated that arsenic uptake by the plants was low, with the highest arsenic level being 60-70 mg kg-1 dry weight in unpeeled potato. Provided the …

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Geochemistry Of Suspended Particles In The Tamar Estuary, John Smith Findlay Jan 1990

Geochemistry Of Suspended Particles In The Tamar Estuary, John Smith Findlay

School of Geography, Earth and Environmental Sciences Theses

ICP analyses of total rare earth element (REE) abundances in intertidal sediments and suspended particles from the Tamar Estuary show little variation in REE concentrations along the estuary and only minor fractionation relative to standard shale. Fe, Mn, Cu, Zn, Ni & Co abundances in the estuarine suspended particles show significant variations in the turbid upper estuary. Acid leachable REE display different shale normalised patterns with slight enrichment of the mid to heavy REE. Sediment porewater analyses confirm the diagenetic mobility of the REE and show significant heavy REE enrichment consistent with their derivation from a non-detrital source. Detailed studies …

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Enzyme Linked Immunological Studies Of Cholinesterases In Human Blood, Jeffrey Wynn Jones Jan 1990

Enzyme Linked Immunological Studies Of Cholinesterases In Human Blood, Jeffrey Wynn Jones

Other Faculty of Health Theses

A modified Ellman method using acetylthiocholine as substrata has been used to reliably measure erythrocyte AChE activity (CV=7%). Reliable immunological quantitation of this enzyme (CV=7%) was achieved using monoclonal antisera to AChE (AE-1 and AE-2) in a fluid phase homogeneous enzyme-linked antiglobulin test (ELAT). AChE activity and antigen levels were similar for both adult male and female samples. Cord samples at term measured 60% of the adult value and reached 100% within 5 months. An overall increase in AChE activity was observed as pregnancy progresses with patients 1 to 3 days post delivery showing significantly elevated levels of activity and …

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Topographically Induced Internal Waves And Enhanced Vertical Mixing In An Estuary, Darrell Richard Mark Sturley Jan 1990

Topographically Induced Internal Waves And Enhanced Vertical Mixing In An Estuary, Darrell Richard Mark Sturley

Other Faculty of Science and Engineering Theses

Stratified tidal flow over topographic features has often been thought to give rise to enhanced vertical mixing in estuaries. So far no estimates have been made of the transfer of energy from the barotropic tide to internal waves, and subsequently to increased potential energy of the water column. Observations have been made over a topographic depression at Cargreen in the Tamar Estuary. This work shows clearly the formation and evolution mechanisms for internal waves on the thermocline, on a neap and a spring tide. On a neap tide an internal wave formed as a nonlinear response to the tidal flow. …

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Chemical Dynamics In North Sea Estuaries And Plumes, Andrew Turner Jan 1990

Chemical Dynamics In North Sea Estuaries And Plumes, Andrew Turner

School of Biological and Marine Sciences Theses

Observational and experimental studies have been undertaken in the southern North Sea environment, including five major estuaries (Humber, Thames, Scheldt, Weser and Elbe), with the aim of elucidating the mechanistic and kinetic details of trace metal reactivity required for the refinement of pollutant transport models. The results of a systematic investigation of suspended particle characteristics (BET specific surface area and porosity, carbon content. Fe and Mn oxide coatings) indicated that, although there exists significant yet explicable variability among the North Sea estuaries, such compositional factors do not exert an observable influence on solid-solution interactions. Furthermore, chemical reactivity was not usually …

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The Immune Response Of The Grey Mullet, Chelon Labrosus (Risso, 1826), To Cryptocotyle Lingua (Creplin, 1825), (Digenea), Bradbury Patrick Wood Jan 1990

The Immune Response Of The Grey Mullet, Chelon Labrosus (Risso, 1826), To Cryptocotyle Lingua (Creplin, 1825), (Digenea), Bradbury Patrick Wood

School of Biological and Marine Sciences Theses

The ability of thick-lipped grey mullet to mount both humoral and cellular immune responses to Cryptocotyle lingua has been demonstrated here for the first time. Of the 3 procedures for immunisation investigated, namely exposure to live cercariae, intraperitoneal (ip) injection of whole killed cercariae and ip injection of a cercarial sonicate, the former gave the highest primary antibody titres with a peak response at 4 weeks post infection. Peak titres occurred at 5 and 7 weeks after immunisation by ip injection of sonicated cercariae and whole killed cercariae respectively. An enhanced secondary antibody response was observed following challenge by ip …

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Intrathermocline Lenses Of The Red-Sea Water In The Indian-Ocean, Sl Meshchanov, Gi Shapiro Jan 1990

Intrathermocline Lenses Of The Red-Sea Water In The Indian-Ocean, Sl Meshchanov, Gi Shapiro

School of Biological and Marine Sciences

No abstract provided.

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The Structure And Function Of Peripheral Blood Leucocytes And Gut-Associated Lymphoid Tissue In The Cichlid, Oreochromis Mossambicus, Teresa Ann Doggett Jan 1989

The Structure And Function Of Peripheral Blood Leucocytes And Gut-Associated Lymphoid Tissue In The Cichlid, Oreochromis Mossambicus, Teresa Ann Doggett

School of Biological and Marine Sciences Theses

The peripheral blood of O.mossambicus was examined using light and electron microscopy and was found to contain four forms of leucocytes: lymphocytes, thrombocytes, monocytes and three types of granulocytes. The monocyte and two types of granulocyte were found to be phagocytic and ingest colloidal carbon and bacteria. The alimentary tract was found to contain a number of leucocytes, some showing a morphological similarity to those in the peripheral blood, while others were unique to the gut tissue. These intestinal leucocytes were found mainly as a diffuse cell population in the epithelium and lamina propria, and only occasionally as discrete lymphoid …

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