Open Access Original Research Article

Water Quality Status of Tono and Vea Reservoirs for Aquaculture Development in the Upper East Region of Ghana

Etornyo Agbeko, Nelson W. Agbo, Thomas K. Agyemang, Daniel Adjei-Boateng

Asian Journal of Fisheries and Aquatic Research, Page 1-14
DOI: 10.9734/ajfar/2019/v3i130022

Understanding aquatic ecosystem dynamics is fundamental to sustainable development of aquaculture. This study explores the water quality characteristics over temporal and spatial scale in Tono and Vea Reservoirs in the Upper East Region of Ghana for aquaculture development. Water samples and in-situ measurements were taken for fifteen months, from February 2015 to March 2016. Monthly water quality monitoring were based on stratified sampling from upstream, midstream and downstream zones of these reservoirs. Standard analytical methods for examination of water were employed during sampling and laboratory analysis of reservoir water quality. Phytoplankton analysis was done using light microscopy to obtain phylum abundance. Multivariate statistical methods were used to investigate water quality dataset obtained. Cluster analysis grouped fifteen months of water quality changes into three seasonality regimes (periods) based on temporal variation. Principal component analysis (PCA) reduced eighteen water quality variables into five and three factors with total variance of 88.26 % and 79.30% for Tono and Vea reservoirs, respectively. With pH > 7 and alkalinity > 20 but < 100 mg L-1 CaCO3, both reservoirs have alkaline water. Dissolved oxygen was > 5 mg L-1. Three phyla of phytoplankton were identified with dominant (in abundance) phylum as Chlorophyta (72%) occurring in Tono reservoir. To understand the spatial relationship using correspondence analysis (CA), the first axis of CA explained 84.2% and 64.3% of total variation in relative abundance of phytoplankton phyla for Tono and Vea reservoirs, respectively. Thus, Cyanophyta showed strong positive association with conductivity, total hardness, nitrate, sulphate, turbidity, water depth and dissolved oxygen which were responsive to the midstream and upstream zones of Tono reservoir. Whiles in Vea reservoir, Chlorophyta under same water quality variable showed responsiveness to the midstream and downstream zones. Reservoir water quality studied were within acceptable limits for fish culture but changes could be linked to anthropogenic activities on reservoir catchment area and seasonality regime. Results from this provide a baseline to enable information to enable assessment of aquaculture impact in Tono and Vea reservoirs. The use of multivariate analysis could be a reliable statistical method for assessing water quality on a spatio-temporal scale.

Open Access Original Research Article

Histo-toxicity of Corexit 9500 Dispersant on Gill and Liver of Clarias gariepinus (Burchell 1822)

O. Taylorharry, A. P. Ugbomeh, K. N. O. Bob-manuel

Asian Journal of Fisheries and Aquatic Research, Page 1-12
DOI: 10.9734/ajfar/2019/v3i130023

The aim of this study was to assess the chronic toxicity of Corexit 9500 on histology of liver and gill of juveniles of Clarias gariepinus. Range finding tests were conducted over a 96-hr period after acclimatization of the test organisms in the C.P. Powell laboratory in the University of Port Harcourt, Nigeria. The test organisms 10/treatment were exposed to the following concentrations of Corexit 9500; 0.00 ml/L, 0.0125 ml/L, 0.025 ml/L and 0.05 ml/L in triplicate. Liver and gill were excised from fish every week for histological assay using standard methods. The LC50 at 96 hrs was 0.115 ml/L. The growth in length and weight of C. gariepinus was significantly higher in the control than the test treatments (p<0.05). Hyperplasias, necrosis of epithelial cells, inflammation of the secondary gill lamella and hypertrophic primary gill lamella were observed in the exposed gills. Hepatic lesions in the liver tissues of the fishes exposed to Corexit 9500 were characterized by hyperplasia, narrowing of the central vein and vacoulations. The alterations observed in the liver and gill tissues indicated that Corexit 9500 may have interfered with transamination and metabolic processes, with the possibility of affecting the physiological functions of the fish in an aquatic environment.

Open Access Original Research Article

Fish Species Composition and Morphological Descriptions of Five Dominant Families from Inland Waters of Kebbi State-Nigeria

D. Y. Bawaa, S. M. Nurul Amin, Aziz bin Arshad, Fatimah Md Yusoff, L. A. Argungu

Asian Journal of Fisheries and Aquatic Research, Page 1-8
DOI: 10.9734/ajfar/2019/v3i130024

A study was conducted on fish species composition and morphological features of five dominant fish families from the inland waters of Kebbi state, Nigeria between January and December 2017. Three major fishing communities (Argungu, Sabiyel and Yauri) were selected for the study. Fish samples were qualitatively collected from the commercial landings of the fishermen using gill nets. The analysis of the distribution of fish species were analyzed using Microsoft Excel software In total 18 fish species belonging to 10 families were identified from the inland waters of Kebbi state. Viz: Bagridae, Cichlidae, Claridae, Mormyridae, Citharacidae, Characidae, Mochokidae, Melaptaruridae, Schilbeidae and Cyprinidae. Among the 10 identified families, Bagridae (22.22%) and Mormyridae (16.66%) which accounted for four and three species respectively, were the most dominant families.

Open Access Original Research Article

Expression of Heat Stress Biomarkers in Wild and Cultured African Catfish Clarias gariepinus (Burchel, 1822)

K. Gbadamosi Oluyemi, R. Osungbemiro Nelson

Asian Journal of Fisheries and Aquatic Research, Page 1-5
DOI: 10.9734/ajfar/2019/v3i130025

The expression of heat stress biomarkers in wild and cultured African catfish Clarias gariepinus was investigated in this study. Twenty wild and cultured fish species of average weight of 400±50g were obtained from Owena dam, (Latitude: 7°20'46.04"Longitude: 4°59'54.99") and a reputable fish farm in Akure, Ondo State.  Ten male and female fish from the two source were all conditioned for 3days in concrete tanks. The fish were stocked in concrete tanks of 2m x 2m x 1m with the stocking density of 5 in each tank and the water quality parameters were monitored. Fish were subjected to hyperthermia-induced shock at 39oC with the aid of a 2-kW heating rod (Binatone, Japan). At the end of the hyperthermia-induced stress. Blood samples were collected to determine the glucose level and the expression of Heat Shock Protein (HSP). The highest glucose level of 50mg /l was found in the cultured male African catfish and the lowest glucose level of 18mg/l was found in wild female African catfish. There was higher diversity and expression of HSP in cultured female fish than the wild male. The result of this study showed that the expression of stress biomarkers in African catfish Clarias gariepinus was influenced by the gender and the environment where the fish was found with the male and wild fishes showing more resistance to stress.

Open Access Original Research Article

Ecological Approach of Plankton Responses to Water Quality Variables of a Tropical River, South-Eastern Nigeria: A Bio-indicator-based Community Assessment of Idundu River

Andem Bassey, C. O. Odey, Esenowo Imeh, Inyang Inimfon

Asian Journal of Fisheries and Aquatic Research, Page 1-17
DOI: 10.9734/ajfar/2019/v3i130027

In the present study, the water quality variables of the Idundu River were assessed by evaluating the Plankton community. Three sampling stations: Station 1 (minimal fishing), station 2 (artisanal fishing area/ cluster of human settlements) and station 3 (fisheries landing area, dredging) representing regions along the stretch of the watershed with considerable economic importance and anthropogenic activity, were selected within the period of six (6) months. The study determines plankton distribution, diversity and some water quality variables of Idundu River, and how they influence plankton abundance. The results of this study reveal that water quality variables (mean ± SD) of the River were pH (6.526 ± 0.104), surface water temperature (26.224 ± 0.106˚C), dissolved oxygen (1.474 ± 0.135 mg/l), nitrate (0.026 ± 0.001 mg/l) and phosphate (0.015 ± 0.000 mg/l). All the water quality variables assessed were within the acceptable range. A total of 23 phytoplankton species belonging to five families, totalling a numerical abundance of 368 individuals/L were observed. Bacillariophyceae was the most abundant phytoplankton family (63.81%), followed by Chlorophyceae (17.41%), Dinophyceae (7.87%), Cryptophyceae (9.77%), and the least abundant was Zygnemophyceae accounting for (1.08%). A total of 20 zooplankton species belonging to five phyla, totalling a numerical abundance of 140 individuals/L were observed. Rotifera was the most abundant zooplankton phylum (35.69%), Arthropoda (30.62%), Ciliophora (17.79%) and Annelida (12.15%); the least abundant was Nemata (2.85%). Principal component analysis (PCA) for plankton organisms showed that phytoplankton were more homogenously distributed than zooplankton during the study period. Shannon Wiener and Margalef’s diversity index showed that the River is in a healthy condition and the equitability level was high across all the stations, indicating even plankton distribution.