Abstract T-cell proliferation studies are traditionally carried out with radioactive reagents or fluorescent reagents that require measurement with advanced technology instrumentation. We attempted to calibrate the optimal conditions suitable for the use of a non-radioactive assay for the measurement of a T-cell proliferation assay in bovine fascioliasis, but applicable to the study of other infectious diseases in our developing 'country setting, Crude antigen extract was prepared from 15 adu...
ABSTRACT Huge quantities of wastes which are indiscriminately disposed into uncontrolled dumpsites and flowing waters around residential areas are generated from Ibadan, metropolis. These may adversely affect soil, surface- and ground-water qualities and the fauna. Limited information exists on toxic effects that wastes from these nondesignated sites have on associated fauna. Earthworms are one of the dominant fauna in soils and are pollution bioindicators. Therefore this study was designed t...
ABSTRACT. An investigation focusing on themolecular forms-of Anopheles gambiae complex and occurrence of the .knockdown resistanceIkdr gene) was carried out from June to July 2001 and August to September 2002 at Igbo-Ora, NigeriJusirig aspirator and DNA analyses; Of the 127 An. gambiae s. I. analysed.fhere were 66 (51:9%):.:tv1and61 (48.03%) S forms, both recorded in An. gambiae s.s. andAnopheles arabiensis. The forms were virtually sympatric throughout the study. Two of the An. gambiae s.s.e...
This work continues the marine tradition o~ the Department o~ Zoology but attempts to open-up a new ~ield by tack].ing for· the first time the ecology of the shaJllow sea bed. False Bay is accessible and provides a large arem that is virtually unaffe.cted by rivers or the works of man. Its' situation happ:ens to be particularly _interesting. It is the nearest part of the flat, submarine shelf called the Agulhas Bank, where there are valuable fishing grounds: and it lies at the boi.mdary of t...
ABSTRACT. The preference of cassava as a major host by Prostephonus truncotus Horn is a major c onstraint to ample production of cassava, tvumibot esculenta Crantz and storage. This study analyzed the nutritional and secondary metabolite compositions in 15 cassava varieties, evaluated levels of damage and reproduction by P. truncatus, and assessed their resistance to attack. One hundred grams 01 dried cassava chips in 250'ml Kilner jars were infested with 10 adult larger grain borerof 0-10 da...
During the course of some years of research into growth-rate and age of South African fishes of commercial importance, amongst wbich are included various species of Heterosomata, 1 the scales of sucb species received a great deal of attention.· In a very short time the characteristics of the sea les thus . examined became so familiar, that it was found poseible to identify any particular species solely from its scales. In a great many instances scale-samples, labelled with the local common n...
In the blood vascular system of a typical fish, the blood is sent from the heart to the gills for oxygenation and thence to the rest of the tissues, before returning once more to the heart. This is a so-called "Single Circulation". Where lungs make their appearance in the vertebrate series however, their blood supply is derived from the last of the aortic arches and is returned via the newly formed pulmonary veins, directly to the heart. A part of the blood leaving from the heart is sent to t...
Abstract Background: Some MSP-119 specific antibodies that inhibit merozoite invasion also inhibit the secondary processing of MSP-1. However the binding of these inhibitory antibodies can be blocked by another group of antibodies, called blocking antibodies, which recognize adjacent or overlapping epitopes, but themselves have no effect on either MSP-1 processing or merozoite invasion. These antibodies have been reported to be present in individuals living in a malaria endemic area. Methods:...
Abstract Phytoplankton community composition in the Southern Ocean (SO) determines levels of primary production, which support marine ecosystems and export of material to the deep sea. Nanoplankton (cell diameters 2-20 µm) are poorly resolved by traditional microscopy, and it is becoming apparent that unknown diversity and ecosystem functionality may be contained in this size class: for example, small diatoms (
Table of Content Acknowledgment Short Abstract General Abstract Chapter 1: Introduction Chapter 2: Stable isotope turnover in blood and toenails: A case study in captive African penguins Chapter 3: Insights from stable isotope into African penguins foraging behaviour during the pre-moult period Chapter 4: Temporal and spatial variation of Cape Gannet diets: lessons from stable isotopes Chapter 5: The pattern and location of moult in White-chinned Petrels Chapter 6: White-chinned Petrel...
Abstract This thesis investigates the impacts of the demersal trawl fishery on infaunal, epifaunal and fish assemblages in the southern Benguela upwelling system for the first time. In the absence of representative areas of similar habitat protected from trawling in the southern Benguela region, infaunal and epifaunal assemblages were compared between heavily and lightly trawled areas to assess the impacts of the otter-trawl fishery. Infauna were sampled at four sites, from southern Namibia t...
ABSTRACT Studies have been carried out at Nguruman, south-western Kenya, on Glossina longipennis Corti, a little known member of the fusca group of Glossina. The first objective was to develop an efficient trap suitable for both sampling and control purposes. Studies were then carried out on the population dynamics of G. 1ongipennis using the newly developed sampling methods. Lastly the trap/odour bait system was tested in a control situation. Replicated Latin square design experiments were u...
Toxicity of ammonia, which can reach toxic levels in aquaculture systems, was investigated for Haliotis midae. Toxic FAN (free un-ionized ammonia) was estimated from TAN (total ammonia nitrogen) measurements. It was found that commonly used Nesslers and Palintest methods underestimated TAN. Tolerance of H midae to ammonia increased with increasing size, as indicated by 36 h LC50 values; farmed juvenile abalone (1 - 2.5 cm shell length) had the smallest LC50 of 9.8 f,lg rl FAN, whereas LC50 wa...
ABSTRACT This thesis addresses the recruitment patterns of barnacles and mussels at a range of spatial and temporal scales and attempts to relate them to larval and adult abundance, as well as to local productivity and oceanographic conditions that would influence larval transport and the connectivity of adult populations. In Chapter 1, I investigated the spatial and temporal patterns of mussel recruitment and adult bed dynamics offour mussel species (Aulacomya ater, Mytilus galloprovincialis...
ABSTRACT This thesis explores the relationships between commercial data and those obtained from research surveys in an attempt to broaden the database available for management, and to cover seasonal and inter-annual changes in density estimates of Cape hake (Merluccius capensis). It also attempts to explain hake variability of in terms of environmental indices based on satellite remote sensing, carefully chosen to reflect underlying oceanographic processes. The influence of various factors on...