DEPARTMENT OF ANIMAL AND ENVIRONMENTAL BIOLOGY

Water quality remains a critical public health concern, particularly in rapidly urbanizing regions like Benin City, Nigeria. This study assessed the physicochemical properties, essential minerals, and potential contaminants in five bottled water brands (EVA, CWAY,
AQUAFINA, EIO, and ROI) to evaluate their safety and compliance with regulatory standards. Water samples were collected from different retail outlets in Benin City and analyzed for parameters such as pH, conductivity, total dissolved solids (TDS), turbidity,
hardness, chloride, sulphate, nitrate, and trace metals using standard laboratory procedures. The results showed significant variations across brands. EIO had the highest pH (7.37 ± 0.19), while ROI had the lowest (6.63 ± 0.11). Conductivity and TDS were highest in EIO (41.33 ± 1.16 µS/cm and 20.67 ± 0.58 mg/L, respectively) and lowest in ROI (12.00 ± 2.00 µS/cm and 6.00 ± 1.00 mg/L, respectively). Hardness levels were within the WHO recommended limits, with CWAY showing the highest value (22.00 ± 2.00 mg/L). Trace metal analysis revealed that ROI had the highest levels of iron (0.12 ± 0.01 mg/L), zinc (0.27 ± 0.05 mg/L), manganese (0.48 ± 0.07 mg/L), and copper (0.52 ± 0.09 mg/L), suggesting possible contamination from natural sources or packaging materials. While most bottled water samples met regulatory standards, ROI exhibited elevated levels of turbidity, suspended solids, and trace metals, indicating potential filtration inefficiencies. These findings emphasize the need for stricter regulatory monitoring and quality control measures to ensure the safety of bottled water in Benin City.

This study evaluated the quality of borehole water in rural communities of Benin City, Nigeria, with a focus on protecting vulnerable populations such as children and infants. Water samples were collected from five borehole locations in the Ogbojobu community and analyzed for both biological and physicochemical parameters. Total coliform counts ranged from non- detectable (0 CFU/100 mL) to 1.0 CFU/100 mL, while fecal coliforms were undetectable across all sites, suggesting minimal microbial contamination. Physicochemical analysis revealed that the pH values of the water were slightly acidic, ranging from 5.60 ± 0.00 to 6.63 ± 0.058, which is at or below the WHO permissible range of 6.5–8.5 for drinking water. Other parameters, including conductivity (14.0–60.0 µS/cm), total dissolved solids (8.0–30.0 mg/L), turbidity (0.0– 2.0 NTU), hardness, alkalinity, chloride, phosphate, nitrate, calcium, magnesium, iron, zinc, manganese, and copper, were measured with significant variations observed between borehole sites (p < 0.05). Notably, lead and cadmium were not detected in any sample. Given that safe drinking water is critical to the health of vulnerable groups, recent studies have emphasized the disproportionate risks heavy metal exposure poses for children and infants. These findings highlight the need for continued monitoring and targeted public health interventions in rural Nigerian communities to safeguard child and infant health from potential chronic exposure to harmful contaminants

The rising global population, expected to surpass 9 billion by 2050, has intensified the need for sustainable animal protein sources. Traditional livestock and aquaculture feeds, such as fishmeal and fish oil, pose ecological and economic challenges, necessitating alternative protein solutions. This study evaluated the potential of Hermetia illucens (Black Soldier Fly Larvae, BSFL) as a sustainable feed alternative by examining the effects of groundnut and watermelon household waste on their growth performance. The experiment utilized three dietary treatments: groundnut, watermelon, and a 1:1 mixture of both. Growth parameters, including weight gain, food conversion ratio (FCR), and proximate compositions were assessed. Results show that larvae fed the mixed diet exhibited the highest weight gain (59.33g) and the most efficient FCR (3.37), compared to groundnut (21.67g, FCR = 9.23) and watermelon (10.67g, FCR = 18.74). Proximate analysis reveals that groundnut provides higher protein (6.88%) and fat (5.67%), while watermelon contributes moisture (33.98%) but lower macronutrient levels. It was found that the mixture of watermelon and groundnut was the best diet for feeding H.illucens larva. The lowest food conversion ratio (3.37) of mixture indicates food utilization efficiency. Proximate analysis disclosed higher value for Fat, Ash, Crude fiber, Protein and Carbohydrate (Ash 0.07, 0.32, 0.56 and 0.81) respectively. In summary, the mixture of watermelon and groundnut is appears to be a better food for raising H.illucens larva.

Tertiary institutions, which provide education and temporary housing for thousands of students, face environmental challenges. This study analyzed water samples from five hostels for microbiological contamination and physicochemical parameters. Bacterial counts ranged from 2 × 10¹ to 1.3 × 10³ CFU/ml, with no coliform or E. coli detected. Proteus was found in samples 1 and 2, while Pseudomonas was present in samples 3 and 4. The analysis revealed acidic pH values between 4.77 and 5.33 and low total dissolved solids (TDS) from 13 to 37 mg/l. Iron concentrations were the highest, ranging from 62.32 to 154.70 mg/kg. Manganese peaked in sample 3 (0 to 15 cm depth) with 34.46 mg/kg. Lead levels ranged from 1.25 to 3.09 mg/kg, and copper levels varied from 4.36 to 11.05 mg/kg. Cadmium levels were stable at 0.01 to 0.02 mg/kg, while arsenic and mercury were not detected. Waste characterization showed that plastics and food constitute a significant portion of hostel waste. Regular monitoring of water quality and maintenance of storage systems can enhance drinking water in student hostels. Improving waste disposal and implementing better waste segregation are also essential to minimize metal accumulation. These actions will significantly enhance waste management and drinking water quality.

Dipterans are excellent indicators of water quality; hence, they are routinely used as bioindicators during monitoring of aquatic ecosystems. The study was therefore, executed to investigate the physico-chemical water quality and dipteran aquatic insect larvae community. Both water and benthic samples were collected between August 2021 and January 2022 at four designated sampling stations along the Okhuahie River at Ikpe in Ikpoba-Okha Local Government Area of Edo State, Nigeria, using standard procedures. A total of 22 physiochemical parameters were determined and measured. Among the physical and chemical parameters, Flow rate, Dissolved oxygen, and Phosphate showed highly significant differences (P<0.001) across the stations. A total of 3 taxa comprising 857 species were recorded. Abundance was highest in station 3 consisting of 146 individuals and the lowest in station 2 consisting of 77 individuals. The dominant taxon is Chironomid (98%), Culex (1.2%) and Tanyderidae (0.3%). Culex consisted of just 1 species and 11 individuals, Tanyderidae of 1 species and 3 individuals, whereas Chironomid comprised 5 species and 843 individuals. The diversity indices showed that station 3 was more diverse followed by station 4, while dipteran species in station 2 was least diverse. Culicidae and Tanyderidae showed positive critical correlation to sulphate and turbidity. The overall abundance showed no significant difference (p > 0.05) for all the four station. This study proved that Okhuaihe River is unperturbed and the Dipteran encountered are characteristics of a tropical freshwater habitat.

Zooplankton and macrobenthic invertebrate fauna are good indicators of the overall water quality of rivers, as changes in water quality affect their general distribution and abundance. This study investigates the community structure of zooplankton and macrobenthic invertebrate fauna of Siluko River, Edo State, Nigeria. Zooplankton and macrobenthic invertebrate samples were collected monthly from July 2016 to March 2017 at four designated stations between 09:00 hours and 12:00 hours using plankton net and filtering 100litres of water respectively and thereafter analyzed in the laboratory using standard methods. A total of 20 zooplankton taxa comprising 386 individuals belonging to the groupCladocera, Cyclopoida, ploimida and flosculariaceae were encountered. Tropocyclops prasinus had the highest number of abundance. Cladocera accounted for 31.00% while Cyclopoida, Ploimida and flosculariaceae accounted for 62.00%, 6.00% and 1% respectively. Shannon-Weiner’s diversity indices showed that highest value of 3.583 was obtained in station 4 and lowest value of 2.731 was obtained in station 2 for the zooplankton. There were no observed seasonal variation in Cladocera and Copepods composition and abundance except for Rotifers which were more abundant in dry season. A total of 52 macrobenthic invertebrates taxa comprising of 2163 individuals, three phyla; Annelida, Arthropoda and Mollusca were encountered in this study. Centroptilum sp. had the highest abundance. Diversity and evenness indices showed that there was no significant difference (p>0.05) in species composition across the study stations. Using the Shannon-Weiner’s diversity index, highest value was obtained in station 1 and lowest was obtained in station 3. Ephemeroptera, Plecoptera, Trichoptera (EPT) index revealed that the water quality at stations 1, 3 and 4 were acceptable while that of station 2 was categorized as good. The zooplankton and macrobenthic invertebrate communities in Siluko River were characterized by species which indicated good water quality. However further studies are recommended to monitor the changes to this water body and their probable health effects as anthropogenic activities such as farming and housing development are on the increase around this stretch of the River.

Freshwater ecosystems are increasingly threatened by environmental stressors, particularly in regions where rivers serve as essential resources for surrounding communities. This study assessed seasonal and spatial variations in water quality and aquatic biodiversity in rivers within Ikpe Community. The research focused on evaluating physicochemical water parameters, analyzing the composition and diversity of benthic macroinvertebrates, and applying a multimetric biological index to determine the ecological integrity of selected rivers including the Orhionmwon River, Irogbe River, and Okhuaihe River.

Water quality parameters such as temperature, pH, depth, flow rate, and chemical concentrations were measured at multiple sampling stations during both wet and dry seasons. Sediment samples were collected using composite sampling techniques, and benthic macroinvertebrates were preserved and identified in the laboratory. Physicochemical analyses followed protocols of the American Public Health Association, while heavy metal concentrations were determined using Atomic Absorption Spectrophotometry. Pollution indices and biodiversity metrics, including the Shannon–Wiener Diversity Index and Simpson Diversity Index, were applied to evaluate ecological conditions.

The results revealed significant seasonal and spatial variations in several water quality parameters, including electrical conductivity, transparency, and river width (p < 0.01). While most measured parameters were within the guidelines of the Federal Ministry of Environment Nigeria, turbidity exceeded recommended limits in some locations. Pollution indices indicated generally low levels of metal contamination, although mild pollution was observed in certain stations. Water Quality Index values ranged from 9.35 to 16.53, classifying all sampling stations as having excellent water quality. Macroinvertebrate taxa exhibited varying sensitivities to environmental changes, with groups such as Ephemeroptera and Diptera responding strongly to habitat alterations, while more tolerant taxa adapted to impacted conditions.

The study concluded that environmental variables such as pH, turbidity, electrical conductivity, and nutrient levels significantly influence macroinvertebrate distribution and diversity in these freshwater ecosystems. Rivers such as Orhionmwon and Okhuaihe were identified as priority areas for conservation due to observable ecological changes. The findings highlight the importance of integrating physicochemical assessments and biological indicators in monitoring freshwater ecosystem health and guiding conservation strategies.

Lentic water bodies in Nigeria are often neglected in favour of flowing systems making them prone to pollution, nutrient enrichment and ecological degradation. This study assessed the zooplankton community structure, physical and chemical characteristics, and water quality of Obazuwa Lake, Edo State, Nigeria.Water and zooplankton samples were collected monthly from May to November, 2024 at three sampling stations. Temperature, pH, and dissolved oxygen (DO) were measured in situ, while other physicochemical parameters were analyzed in the laboratory using standard procedures. Zooplankton specimens were identified using recognized taxonomic keys. Data was analyzed using descriptive statistics, one-way Analysis of variance (ANOVA) to test for spatial variation and Pearson’s correlation to assess relationships between biotic and abiotic components. Water quality index (WQI) was computed to classify lake water quality. Multivariate analysis such as Canonical Correspondence Analysis (CCA), Principal component analysis (PCA) and Redundancy Analysis (RDA) was also used to identify community patterns.

Heavy metal contamination in aquatic ecosystems is a growing concern due to its persistence, bioaccumulation potential, and toxicity to both wildlife and humans. Amphibians, due to their permeable skin and dual aquatic-terrestrial life cycle, serve as critical bioindicators of environmental pollution. However, traditional bioaccumulation studies often involve lethal sampling, which can negatively impact amphibian populations already facing global decline. This study employed a non-lethal sampling technique using toe clips from amphibians to assess heavy metal contamination in water, sediment, and amphibian tissues from Ikpe River, Edo State, Nigeria, the amphibian toe clips were collected between the months of January to September 2022.
The concentrations of iron (Fe), zinc (Zn), copper (Cu), manganese (Mn), lead (Pb), cadmium (Cd), and nickel (Ni) in surface water, sediment, and amphibian toe clips with the aim of evaluating the effectiveness of amphibian toe clips in the assessment of heavy metals accumulating in amphibians from three stations along Ikpe River, influenced by anthropogenic activities. Analysis of heavy metals in the samples were carried out using Atomic absorption spectroscopy (AAS)