Survey of fungal infestation of some fish species from Tagwai dam, Minna, Niger State

Survey of Fungal infestation of some species of fish in Tagwai Dam Minna was carried out from March to June 2002. Fungi were isolated from the scale/skin, gills and fins. Twenty-one fungi species were identified from 18 species of fish microbial growth was measured by direct cell count using Stuart colony counter. Most of the fungi encountered were of the mould group and infestation occurred among all the species sampled. The infestation was predominantly by Aspergillus species and the scale/skin was most widely affected. The study showed the identified fungi in order of frequency to be as follows. Aspergillius niger. Rrhizopus spp. Mmucor spp Aspergilus flavum. Aspergillus parasitous. Aspergillus fumigatus, Microsporum canis. Penicillum virridicalumand Fusarium spp respectively. Aspergillus niger occurred on all the species of fish sampled. Barrilius spa and Chrysichrhy auratus longifilis had significantly higher (P0.05) in the mean fungal load in different parts of the body of other fish species sample

China in Africa: A New Scramble

This paper looks into the nature of China’s involvement with African nations, which is a highly debated issue in recent times. Supporters of African nations’ relations with China argue that African countries have enjoyed increased trade, aid and investment from these relations; skeptics, however, worry that these relations may be reminiscent of European colonization, hinging upon unequal exchange and the exploitation of Africa’s resources and people. This paper interrogates whether theories of Western colonization, imperialism, and dependency by John Hobson, Vladimir Lenin, Rosa Luxemburg and David Harvey can explain the current context and conditions of China’s role in Africa. I also employ a case study to look into this issue: that of land grabs in Africa. Land grabs mostly involve the expropriation of land in developing countries to facilitate food production and resource extraction to meet demand in more developed countries. While many regions of the Global South have been subject to land grabs, the bulk of these has occurred in Sub-Saharan Africa in recent times. Focusing on China’s role in the land grabs in the Democratic Republic of Congo (DRC), the case study explores the economic and political aspects of China’s agricultural investments in the DRC, and the effects of this on dependency and unequal exchange. Through such an analysis, the relationships between capitalism and incipient, contemporary forms of domination and resource control may be unpacked

Trace metals of River Chanchaga and tap water in Minna Township, Niger State, Nigeria

The study assessed heavy metal (Copper, iron, potassium, sodium, lead, magnesium, manganese and calcium) concentration of River Chanchaga and tap water for public consumption and fisheries in Minna Township from June to November 2004. There were variations in the concentration of these metals during the sampling period, but they all fell within tolerable limits for both fish culture and for public water consumption. The mean concentration for some of these metals were Sodium (6.1 0-8.83mg/I), potassium (2.84-3.56mg/l) and copper (0.27-3.40mg/I)

Text-Independent Speaker Identification using Statistical Learning

The proliferation of voice-activated devices and systems and over-the-phone bank transactions has made our daily affairs much easier in recent times. The ease that these systems offer also call for a need for them to be fail-safe against impersonators. Due to the sensitive information that might be shred on these systems, it is imperative that security be an utmost concern during the development stages. Vital systems like these should incorporate a functionality of discriminating between the actual speaker and impersonators. That functionality is the focus of this thesis. Several methods have been proposed to be used to achieve this system and some success has been recorded so far. However, due to the vital role this system has to play in securing critical information, efforts have been continually made to reduce the probability of error in the systems. Therefore, statistical learning methods or techniques are utilized in this thesis because they have proven to have high accuracy and efficiency in various other applications. The statistical methods used are Gaussian Mixture Models and Support Vector Machines. These methods have become the de facto techniques for designing speaker identification systems. The effectiveness of the support vector machine is dependent on the type of kernel used. Several kernels have been proposed for achieving better results and we also introduce a kernel in this thesis which will serve as an alternative to the already defined ones. Other factors including the number of components used in modeling the Gaussian Mixture Model (GMM) affect the performance of the system and these factors are used in this thesis and exciting results were obtained

Assessment of physico-chemical parameters of River Kaduna and College of Agriculture and Animal Science Dam, (CAAS) Kaduna, Nigeria

River Kaduna is one of the major sources of water to the inhabitants of the communities around the river and also to fish farmers while College of Agriculture and Animal Science Dam (CAAS) is used for fish farming and also for domestic purpose. The study was carried out to assess Physicochemical Parameters of River Kaduna and College of Agriculture and Animal Science Dam, Kaduna. The result of seasonal variation of physicochemical parameters between River Kaduna and College of Agriculture and Animal Science Dam, revealed that the atmospheric temperature (AT) ranged from 32.8 to 33.60C, pH at 7.1, conductivity ranged from 83.7 to 139.7µs/cm, dissolved oxygen ranged from 9.2 to 9.4 mg/l, biological oxygen demand ranged from 5.2 to 5.9 mg/l, water temperature (WT) at 29.20C, total hardness ranged from 37.4 to 58.0 mg/l, alkalinity ranged from 18.8 ton29.7 mg/l, chloride ranged from 14.8 to 15.9 mg/l, nitrate and phosphorus ranged from 0.1 to 0.2 mg/l while transparency ranged from 21.4 to 22.3 cm respectively. The seasonal variation result revealed that both at the Dam and river, AT, pH, DO, WT, Chloride, Nitrate, Phosphorus and Transparency values were not significantly different while conductivity, BOD, TH, Alkalinity and Ammonia were significantly different. However, they were significantly difference from one month to another (wet and dry season months respectively).Keywords: Physico-chemical parameters, River Kaduna, CAAS Da

The effects of light and dark exposure on growth response of Clarias gariepinus fingerlings reared in glass aquaria

The study was carried out to determine the effect of light and dark exposures on the growth response of Clarias gariepinus fingerlings. A total of 120 four-week old Clarias gariepinus fingerlings (mean weight 0.52g~c0.02) were stocked into 20 litres of bore-hole water in glass aquarium (60x30x30) cm. Complete light, dark and normal photo periods were the experimental conditions evaluated. Growth indices such as mean weight gain and mean increase in standard lengths were significantly (p<0. 05) highest in the dark exposure with the following values respectively: (4.19 ~c 0.02g) and (4.11 ~c 0.19cm). Also, percentage survival (82.5%) in the dark exposure was higher than light and control (45% and 70% respectively). Light exposure had higher cannibalism rate (42.5%) than the dark and control (0% and 5 % respectively). Deep shiny black skin colouration was observed among the fingerlings in the dark exposure, while those in the light and control experimental conditions exhibited lighter and normal skin colourations respectively. The experimental conditions were not influenced by the water quality parameters (mean pH: 8~c 0.1 and temp: 28.1 ~c 0.60 ~'C) since their values were within the tolerable limit for fish culture throughout the 42 days experimental period

Histopathological and haematological effects of acute toxicity of cypermethrin on Clarias gariepinus juvenile

The experiment was conducted to evaluate the acute toxic of cypermethrin, a synthetic pyrethroids on juveniles of Clarias gariepinus. The effect was assessed based on the comparism results of haematology and histopathological tissues examinations of control and experimental group exposed to five nominal concentration of cypavest, 10EC Pesticide Preparation (active substance 100mg/l) of cypermethrin in a static non-renewal bioassay for 96 hours. The 96hrs LC50 value of the exposed juveniles was found to be 0.062 mg/1. Fish exhibited progressive loss of balance, respiratory distress, erratic movement and death. Examination of haematology significantly showed higher value (P<0.001; 0.01) of white blood cell (WBC), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), packed cell volume (PCV), monophilis and heterophilis; a significant reduction (P<0.001, 0.01) in Red Blood Cell (RBC) and Lymphocyte was obtained as compared to the control. Severe necrosis, haemorrhages vacuolation, congestion and focal interstitial haemorrhages were the stopathological changes in the tissues of gill and liver, thus concluding that cypermethrin is toxic to juveniles of Clarias gariepinus

Optimization of the expression of tetracycline monooxygenase (Tetx)

Tetracycline is an important group of antibiotics used for agricultural and clinical purposes to treat infectious diseases caused by pathogenic bacteria [1]. It functions by selectively binding to the 30S subunit of the prokaryotic ribosome to effectively halt protein synthesis [2]. Its efficiency in clinical settings is being threatened by an increasing number of antibiotic resistant strains of bacteria. Resistance has been shown to occur through active efflux, ribosomal protection and from the enzymatic degradation catalyzed by flavin dependent enzymes [3]. One of these enzymes is tetracycline monooxygenase (TetX), which has been shown to degrade the antibiotic by monohydroxilation and enzymatic breakdown. The aim of this research is to develop strategies to combat antibiotic resistance in pathogenic bacteria through rationale design of inhibitors of TetX. Study of the kinetic mechanism that will initiate this aim has been limited due to less amount of TetX enzyme produced [6 mg/L of culture] as reported by Wright et al [2]. My research leads off to produce large quantities of active TetX needed for the proposed study. We successfully transformed the plasmid encoding TetX gene plasmid pET22a+ onto competent Escherichia coli cells Rosetta (DE3) pLysS and DH5α. With a developed expression trial protocol (at different induction temperature and incubation period), and novel activity assay (ratio μM oxygen consumed/s to total amount of protein in sample), we were able to determine which cell strain best expresses the enzyme. We discovered that DH5ά with an induction period of 20hrs at 300C had the highest specific TetX activity under all conditions used (725 ±10 U/mg). This was a breakthrough as subsequent experiments on this research will be based on this condition for its detailed catalytic mechanism. We further developed a procedure to obtain large amounts of active enzymes. It was observed that addition of Flavin Adenine Diphosphate (FAD) cofactor to lysis buffer, upon lysing the cell, increased the specific activity, ~9 fold higher (3900 ± 250) with less error as compared to the previous activity recorded. This increase was proposed to be due to FAD binding with the protein thereby making it more stable and thus preventing the enzyme from denaturing while been extracted from the cell. This was yet another breakthrough as this will allow for the accurate determination of the kinetic mechanism of the enzyme which will result in the propagation of errors from multiple kinetic assays by varying the concentration of oxygen and tetracycline. Screen of DH5ά colonies to further determine which colony produces the most amount of TetX, the chosen colony had a specific activity of 9800 ± 250 (~15 fold higher) with 5% error and a yielded stock of ~20 mg/L of TetX more than twice the amount previously reported [2]. This will aid this research group in developing a purification protocol for the detailed kinetic study of the enzyme

Fish communities of Tagwai dam, Niger state, Nigeria.

This study on fish species, generic and family diversity and abundance of Tagwai Dam was carried out for 12 months. Five landing sites were located close to the dam and were all sampled to determine the fish species in the dam. Data was collected from the fresh landing sites from artisanal fishermen bi- weekly. Twelve (12) species belonging to nine (9) genera and six (6) families were indentified. Two (2) families had the highest species diversity having four species each. They include Bagridae [Chrysichthys nigrodigitatus, Chrysichthys furcatus Auchonogtanis, biscitutus, Auchnoglanis occidentalis], Cichlidae  (Hemichromis fusciatus, Tilapia galilea,Ttilapia zilli, Tilapia galilea, Tilapia mariae}. The total count of fish sample during the study period was 326673. Cynothrissa mento had highest population of 247477 while Auchinoglanis occidentalis had the lowest population of 125. There was no significant difference (p>0.05) between the family and species of Bagridae and Cichlidae and also between the families and species of Characidae, Cypirinidae, and Clariidae but the family Clupeidae was significantly (