Thesis (M.Sc. (Zoology)) --University Limpopo, 2013 / Major anthropogenic activities such as, mining, coal-fired power stations and intensive agricultural practices in the upper catchment area of the Olifants River, have a dramatic impact on the water quality downstream. As a result the river is presently the third most polluted river in South Africa. The aim of this study was to assess the impact of water and sediment quality on the health of Labeo rosae and Schilbe intermedius. The aim was accomplished by applying the Fish Health Assessment Index (HAI) which includes the Parasite Index (PI) at Flag Boshielo Dam in the Middle Olifants River, Limpopo Province. This was achieved through; assessing the water quality of the dam by determining the levels of physical and chemical constituents in the water at three sampling sites, determining the bioaccumulation of selected metals in the muscle tissue of the two fish species, assessing the fish health (including the fish condition factor) and the fish parasites in the dam by using the fish HAI and PI, and ascertaining the Human Health risk factor upon consumption of fish contaminated with metals from the dam. The water and sediment quality were seasonally sampled at three sites in the dam: inflow, middle and wall. Dorsal muscle tissues from both fish species were collected for metal bioaccumulation analyses. The water, sediment and fish muscle tissue samples were analysed by an accredited laboratory by means of ICP-OES spectrometry. For the fish health and parasites, ten fish per species were collected seasonally (July 2009 to April 2010) by means of gill nets and examined at a field laboratory using the HAI and PI protocol. Generally the water quality of Flag Boshielo Dam was acceptable for aquatic ecosystems according to the SAWQG with the exception of phosphorus and some metals at the inflow area. The pH ranged between slightly acidic to alkaline values; water temperature: 15°C to 26°C; water hardness medium soft, salinity within the freshwater range; turbidity in the clear water range. The TDS and major ions (salts) were acceptable for the duration of the study. The highest concentrations of nutrients (specifically phosphorus) as well as metals (aluminium, cadmium, copper, iron and lead) were recorded at the inflow area of the dam. The nutrients were very low except the eutrophic range phosphorus concentrations recorded at the inflow whereby, the Elands River may be an additional source of nutrients into Flag Boshielo Dam. The metals that were recorded above TWQR are; aluminium, cadmium, copper, iron and lead, of which were mostly recorded at the inflow. However, statistically there was no significant difference among the three sampling sites. The metal concentrations at the inflow were recorded only slightly higher than the middle and the dam wall. The main source of the metals may be the water coming from catchment area of the dam given the intensive agricultural activities taking place between Loskop Dam and Flag Boshielo Dam. Sediment and bioaccumulation: All the metals were recorded at higher concentrations in the sediment than in the water and fish muscle tissue, except antimony, selenium and strontium. The most abundant metals recorded in the sediment were iron and aluminium. However, the concentrations above the TEL were cadmium, nickel and zinc. The elevated metal concentrations in the sediment are indicating that the metal load in the sediment of Flag Boshielo Dam could be a potential risk for the aquatic biota if they become bioavailable. Antimony, selenium and strontium metal concentrations were recorded at higher concentrations in the muscle tissue of both fish species than in the sediment and water. Iron was the most accumulated metal in the muscle tissue of both fish species. In terms of numbers, more metals were recorded in the muscle tissue of S. intermedius than in L. rosae however the metal concentrations were higher in the latter. This can be attributed to their different trophic levels in the food chain; L. rosae is a primary consumer while S. intermedius is a tertiary consumer. However, the metals that accumulated in the fish muscle tissue were indicative of bio-availability of the toxic metals in the dam and not water/sediment pollution. According to a Human Health risk assessment (Chapter 3), metals that may have risks upon consumption of L. rosae are; antimony, arsenic, chromium, iron and vanadium; for S. intermedius are; antimony, chromium, iron, vanadium and arsenic (in descending order). These metals may pose toxic and carcinogenic risks to humans. Therefore, the rednose labeo (L. rosae) and to a lesser extend the silver catfish (S. intermedius) fish species from Flag Boshielo Dam may not be suitable for humans if consumed above 350 g per week. Fish health and parasites: The Health Assessment Index (HAI) values of the two fish species differed significantly with higher index values recorded for S. intermedius than L. rosae. Besides the Parasite Index (PI), abnormal haematocrit readings, liver conditions, skin lesions and clubbed gills are the necropsy anomalies that contributed predominantly to the HAI. Overall, the PI contributed mostly to the total HAI value. The parasite load and therefore also the mean intensity, mean abundance and prevalence of S. intermedius were higher during all seasons than that of L. rosae. The dominant ectoparasites for both species were from the Class Monogenea and the dominant endoparasites were nematodes. Out of 40 L. rosae sampled, 139 parasites were retrieved; five parasite species were ectoparasites and two endoparasites. From the 40 S. intermedius sampled, 2473 parasites were retrieved, from which two species (one genus) were ectoparasites and three species were endoparasites. The condition factor is used to compare the “condition”, “fatness” or wellbeing of fish and it is based on the hypothesis that heavier fish of a particular length are in a better physiological condition. The L. rosae had a better condition factor, recorded at values less than (2) as compared to S. intermedius (>2). The cause of the HAI necropsy anomalies may have been also from parasite load other than the metals in the water and sediment. However, the HAI alone cannot be used for metal pollution, unless it is done in conjunction with a histopathological study of the tissues/organs. Therefore, the cause of the recorded anomalies from both fish species is inconclusive. On the hand, fish can be used as bioindicators because the accumulated metals in the fish tissues are indicative of the bioavailability of metals in Flag Boshielo Dam.

Rainbow trout were exposed to aluminum at pH 7.25 and 8.25 and four hardnesses (10, 30, 80, and 120 ppm CaCO₃) for 96 hours in a continuous-flow system and mortality and aluminum accumulation in the gills were determined. Temperature, pH, and dissolved oxygen were measured daily for each treatment. Dissolved and total aluminum concentrations and hardness were determined following exposure periods of 48 and 96 hours. Aluminum was most toxic at pH 8.25, and was more toxic at lower than at higher hardnesses. Water hardness provided a significant protective effect against aluminum-induced mortality (p < 0.05), and there were no significant effects for water hardness on gill accumulation at either of pH. At pH 7.25 no mortalities occurred under any conditions. At pH 8.25, the accumulation of aluminum in gill tissues was higher than for pH 7.25 following exposure for 96 hours. In addition, aluminum concentration and exposure time had a significantly cumulative effect on fish mortality (p < 0.05). Possible mechanisms for aluminum toxicity and the accumulation of aluminum in the gills of rainbow trout were attributed to the forms and solubilities of aluminum species at different pH values. Competition between Ca²⁺ and aluminum for binding sites on the gills likely influenced aluminum toxic action. / Graduation date: 1992

Temperature, conductivity, and Aeromonas hydrophila density were determined bimonthly at six sites in the White River drainage system, Delaware County, Indiana, from April, 1984 through December, 1984. Fish were collected from four of the six sites. Fish were identified to species, examined for gross pathology, and their blood collected. Titers against A. hydrophila antigen 157 were determined for all carp (Cyprinus carpio) captured. Certain carp serum samples were also tested against three additional A. hydrophila antigens.Aerononas hydrophila densities appeared to be related to temperature and conductivity, primary producers, and runoff/effluent. Aeromonas hydrophila densities were higher in areas affected by urban runoff/ effluent than in areas affected by rural runoff/effluent. Aeromonas hydrophila densities increased as one progressed through the city of Muncie.Only five percent of all fish captured exhibited signs of gross pathology. Diseased fish typically demonstrated low titers against antigen 157. Several A. hydrophila serotypes were apparently infectious for the carp studied. Thirty-two percent of the carp sampled exhibited a positive titer response against antigen 157. Considerable variation in titer response existed between individuals.Ball State UniversityMuncie, IN 47306

M.Sc. (Zoology) / Please refer to full text to view abstract

M.Sc. / The occurrence of invertebrates in drinking water supplies is a common consumer complaint with studies showing that very few drinking water distribution networks are totally free of organisms. A detailed investigation of different types of metazoan animals in the drinking water supply networks of South Africa has not been undertaken. In limited worldwide studies, invertebrates (mainly Amphipoda, Chironomidae, Cladocera, Copepoda and Ostracoda) have been detected in produced drinking water. In countries that have started monitoring these organisms, the quality of the produced water has improved due to the improved methods of filtering. The occurrence of “worms” (Nematodes and Diptera) and Crustaceans decreases the aesthetic value of the drinking water, and pathogenic organisms, which may also be associated with them, can affect human health. Limited reference works have been compiled during the conducted studies on drinking water distribution networks throughout the world. All fresh water invertebrates have the potential to be passed into the drinking water supply network (Rising mains, pipelines, reservoirs, and consumer taps). There are few complete reference works available for fresh water invertebrates occurring in the fresh water sources and those of Southern Africa. Therefore, there are no reference works regarding fresh water invertebrates that can be used to monitor drinking water supply networks in South Africa. / Prof. J.H.J. van Vuren

Thesis (M.Sc. (Zoology)) -- University of Limpopo, 2020 / The present study was carried out in the Kwena Dam, with the aim of determining selected water quality parameters, parasite diversity and condition factor (K) of Clarias gariepinus (sharptooth catfish), Cyprinus carpio (common carp) and Oreochromis mossambicus (Mozambique tilapia). This study was conducted in autumn (April 2016), winter (July 2016), spring (October 2016) and summer (February 2017). The present study was the first to investigate the parasite composition of these three fish species in the Kwena Dam. A total number of 26 Clarias gariepinus, 21 Cyprinus carpio and 57 O. mossambicus specimens were collected using gill nets of different mesh sizes (30 mm – 120 mm). Each fish was weighed, measured and euthanised by severing the spinal cord. Mucus smears from the skin, fins and gills were examined for ectoparasites using a stereo-microscope. The fish were then dissected and all organs examined for endoparasites. All parasites were fixed and preserved according to standard methods for each parasite group. In situ water parameters were determined using a handheld multi-parameter instrument for each sampling season. In addition, water samples were collected seasonally and sent to an accredited laboratory where they were analysed for selected metals and nutrients. Water quality parameters and the presence of metals in water are of importance in determining the water quality of an aquatic environment. Most water quality parameters were within the Target Water Quality Range (TWQR) for aquatic ecosystems. Aluminium, selenium and zinc had concentrations above the TWQR for aquatic ecosystems. Nutrient concentrations were within the TQWR during all sampling seasons. The water quality did not differ significantly between seasons during the present study. Four parasite groups were reported infecting Cyprinus carpio and these included Monogenea (Dactylogyrus extensus and Dactylogyrus minutus), Digenea (Diplostomum sp.), Cestoda (Atractolytocestus huronensis), Branchiura (Argulus japonicus) and Copepoda (Neoergasilus japonicus). Parasites collected from Clarias gariepinus belonged to four groups, namely Protozoa (Trypanosoma sp.), Monogenea (Quadriacanthus sp. and Gyrodactylus sp.), Nematoda (Paracamallanus cyathopharynx and Contracaecum sp.) and Branchiura (Dolops ranarum). Parasites collected from O. mossambicus belonged to five groups, namely Monogenea (Cichlidogyrus halli, Cichlidogyrus sclerosus, Cichlidogyrus tilapiae and Enterogyrus conoratus), Nematoda (Contracaecum sp.), Cestoda (Neogryporhynchus sp.), Acanthocephala (Acanthogyrus tilapiae) and Branchiura (Dolops ranarum). iv The number of parasite species for the four seasons were as follows: summer (13) > autumn and winter (12) > spring (11). From the Shannon-Wiener index results, O. mossambicus had a higher parasite diversity than Clarias gariepinus and Cyprinus carpio. The Parasite Index (IP) and Inverted Parasite Index (IPI) of the three fish species indicated that the water from the dam is not polluted. The condition factor (K) for all fish species indicated that fish collected from the dam during all sampling seasons were in a good condition and parasite load had little effect on K for all fish species. The use of PI and IPI in conjunction with the fish K can be regarded as a useful tool in freshwater and fish health monitoring. The present results report new geographical records of the parasites of Clarias gariepinus, Cyprinus carpio and Oreochromis mossambicus. Since no parasitological research was done before the present study at the Kwena Dam, the results of the present study form baseline data for future parasitology studies and can consequently be useful in the management and conservation of the Kwena Dam. / DSI–NRF SARChI Chair (Ecosystem Health) of the University of Limpopo and the Limpopo Department of Economic Development and Tourism (LEDET)

The most appropriate and widely used source of drinking water for the rural populations of South Africa is groundwater. Pilot studies and surveys conducted by the Department of Water Affairs and Forestry (DW AF) indicated that there are a number of boreholes across the country that contain apart from fluoride, levels of nitrate, some heavy metals, total dissolved solids, sulphates and faecal coliform (in isolated regions) that could pose a health risk if the water is used for drinking purposes. Very few boreholes have been tested for heavy metals or toxic organic substances. However considering the levels of fluoride, in general, groundwater is of acceptable quality except for some provinces in which elevated levels of natural groundwater fluoride occurs. Very high levels of fluoride, >4 mg/l occur in some groundwater sources in all nine provinces of South Africa, especially in the Limpopo, North-West, Eastern Cape, Northern Cape, Western Cape and KwaZulu Natal provinces. A superficial inspection reveals that most of the local people in those areas suffer from dental fluorosis at varying degrees. The main aim of this study is to determine the distribution of the fluoride ion concentration levels in South African groundwater and the impacts thereof on dental health. The available data is used to assess the distribution of the various fluoride ion concentration levels in some national groundwater sources. Areas of particularly high or low fluoride levels are identified. Results from an epidemiological survey carried out by the National Department of Health (NDOH) are used concurrently with the fluoride data to determine the percentage morbidity of dental fluorosis in each area The results are compared in order to determine if any relationship exists between the occurrence of fluoride in drinking water and the incidences of dental fluorosis. Vegter's lithostratigraphy and the simplified geology of South Africa are used to interpret the results and assess the role of surface geology in the release and distribution of fluorides in groundwater. The role of other factors such as climate and the interactions of the fluoride ion and other water quality parameters in aqueous media are also assessed. / Dissertation (MSc (Water Utilization))--University of Pretoria, 2006. / Chemical Engineering / unrestricted

Four experiments were carried out with broiler chicks from day-old to three or four weeks of age to assess the effects of nitrates and nitrites from calcium, potassium, and sodium salts in the drinking water of broilers on growth, body weights, feed utilization, blood chemistries, liver tissues, and lipid oxidation of breast and thigh tissues. Body weights were lower (P<.05) among chicks consuming calcium nitrate than those of chicks consuming sodium nitrate or the control. Chicks consuming calcium nitrate (Ca(NO���)���) at 1000 ppm had lower (P<.05) body weights than those drinking Ca(NO���)��� at 0, 50, or 200 ppm. Broilers receiving 1000 ppm of calcium nitrite (Ca(NO���)���) had depressed body weights when compared to chicks consuming 0, 50, or 200 ppm of Ca(NO���)���. Consumption of sodium nitrate (NaNO���) at 2033 ppm reduced (P<.05) broiler weights in comparison to broilers ingesting 0, 111, or 427 ppm of NaNO���. Feed utilization was less efficient (P<.05) by chicks ingesting Ca(NO���)��� and calcium, potassium, or sodium salts of nitrite when compared with the control. / Graduation date: 1996

Subterranean ecosystems are regarded as the most extensive biome on earth, comprising terrestrial and aquatic systems - the latter constituting freshwater, anchialine and marine systems. This system plays a key role in the distribution and storage of freshwater, once it contains 97% of the world’s total liquid freshwater (Chapter 1), which has been progressively explored in quality and amount. Initial observation of the subterranean environment began with speleological studies by the recognition of a typical fauna adapted to live inside caves. The first studies to provide information about aquatic subterranean fauna commenced in Slovenia, with the description of the Proteus aguinus by Laurenti in 1768. After an initial faunal classification by the Danish zoologist Schiödte (1849), the Austrian naturalist Schiner (1854) established the most commonly used classification for cave fauna and a great portion of modern research dealing with ecobilogy of aquatic subterranean fauna has mostly evolved from the European biospeleology (Chapters 1 and 3). Studies in biospeleology have made a significant contribution to the progressive knowledge in aquatic subterranean ecology, especially in those circumstances where the access of the underground through smaller voids (e.g. crevicular spaces) is not possible. Accessibility to the underground environment is in fact a negative factor that has led a large number of studies consider about subterranean fauna initially being limited to caves. Spatial constraint was (and still is) a limiting factor in accessing a diverse range of subsurface habitats, although during the last decade, modern research has been using advance technology as a tool to overcome the physical barriers to subterranean research. For a long time the classification of subterranean aquatic organisms was an unclear subject, with the classification subterranean fauna mostly related to terrestrial cave fauna (troglofauna). The classification system dealing with aquatic subterranean groups (stygofauna) is more recent. A few nomenclature schemes have been proposed to describe these relationships, based on morphological, behavioural, and ecological adaptations of animals to the underground life and their level of relationship with groundwater (Chapter 4). The prefix “stygo” is suggested as the most descriptive to refer ecologically to a group of animals related to groundwater habitats. Groundwater related fauna (stygofauna) is comprised by groups of animals encompassing aquatic surface, intermediate and subterranean habitats. They represent diverse group of animals that have different interactive relationships with the groundwater habitat. Some may transact between surface water and groundwater systems, while others spend the whole life cycle in the subterranean voids (Gibert et al., 1994). This transition zone between surface streams and groundwater is recognized as a critically important boundary or ecotone, constituted by a habitat that contains a reservoir of invertebrate fauna biodiversity. It is therefore from the study of karst systems that most information on groundwater ecobiology is resourced, once the open structure of most karsts terrains promotes a number of caves, streams, crevices, sinkholes, and springs to allow human access. Karst systems are well fractured because of the relation between the rock mass and the action of meteoric water, as well as the dissolution rate of calcium carbonate rocks that high. The latter increases with time, producing a terrain with a great drainage potential (Chapter 2). Once porosity is high and the flow of percolating water is fast, it allows good vagility for subterranean fauna and nutrients, as well as penetration of contaminants. In subterranean karsts, much water saturates some areas inside rock spaces. The saturation in the rock in turn promotes large water pockets, known as aquifers. When these groundwater aquifers are found to be interconnecting with the adjacent ecosystems, they became active eco-hydrological components, due to their key participation in the surface-groundwater continuum. Groundwater has different degrees of importance, depending on the available sources of surface water. In many countries it supplies a significant proportion of urban and rural drinking water, industrial, and agricultural. Yet, groundwater systems are “hidden”, difficult in access and to study (Chapter 4, 5 and 7), consequently the recognition of the groundwater aquifer as a natural resource that needs to be protected is largely ignored. Moreover, studies in the ecobiology and distribution of stygobitic invertebrates (Chapter 5), and the need to identify a frame of methods for quality assessment and the suitability of groundwater invertebrates as bioindicative elements, has not been developed (Chapter 6). Finally, strong management and public education programs are required to emphasize the need for a better understanding of the nature of groundwater resources, their participation and complexity (Chapter 8), with the conceptualization of the groundwater aquifer integrity as an ecosystem still receiving little attention in South Africa. / Dr. J.F. Durand Prof. G.J. Steyn

M.Sc. (Aquatic Health) / Aquatic ecosystems in rural South Africa have been impacted over many years by commercial and subsistence anthropogenic activities (DWAF, 2001). These impacts include commercial and subsistence farming, domestic use (e.g. washing of clothes, cars and bathing) and recreational use (e.g. fishing). In the northern parts of the Limpopo Province of South Africa (Vhembe District) the land use is primarily dominated by various agricultural activities and human settlements. Rivers in this region flow through mixed agricultural use, including commercial agriculture (tea and timber plantations) as well as subsistence farming and housing. Perennial rivers in this region include the Mutale, Mutshindudi and Tshinane rivers. These rivers are located in the Water Management Area 2 (WMA 2 Luvuvhu-Letaba) (Kleynhans, et al., 2007a). They are highland river systems, originating in the nearby Soutpansberg Mountain, and these rivers all form part of the larger drainage system of the Luvuvhu River, a tributary of the Limpopo River. The wetlands in the catchment of these rivers are also heavily utilised by the local communities (Working on Wetlands, 2013) used for grazing, sand mining and subsistence cultivation, thus providing a livelihood for the surrounding communities (SANBI, 2012). The aim of the study was to assess aspects of the biological integrity of the Mutale, Mutshindudi and Tshinane rivers. This study formed part of a larger study that included assessments of both abiotic and biotic aspects of these river systems. For this study, the focus was on assessing the fish community structure through the application of Fish Response Assessment Index (FRAI), riparian vegetation through the application of Vegetation Response Assessment Index (VEGRAI) and fish health aspects with special reference to liver and gonadal histopathology. Water quality parameters were found to be within the target water quality range for aquatic ecosystems. The results did however vary between upstream and downstream sampling sites. Similarly, compared to upstream sites, the FRAI showed the Mutale River to improve in fish community structure whereas the Tshinane and Mutshindudi rivers showed a decrease in the FRAI score. The VEGRAI results showed a decrease in EcoCondition in the Mutale and Mutshindudi rivers whereas the Tshinane indicated an increase. This can be attributed to land use change up to the edge of the river systems. Visual observation at the various study sites showed a definite localised impact of human activities on the beds and banks of many parts of the rivers. No histological alterations were identified in any of the gonadal or liver tissue of the Chiloglanis pretoriae (Shortspine suckermouth) (Van der Horst, 1931) and the fish were found to be in a healthy condition according to the selected parameters (gonads and livers) assessed. The fish community structure of the three rivers were found to be in a moderately to largely modified condition according to the ecological state categories calculated. However, the fish health assessment showed no histological alterations in the sampled fish. It is proposed that future studies investigate the influence of the domestic use of the rivers as well as attempt to quantify the impact of agriculture on the system.