ANIMAL AND ENVIRONMENTAL BIOLOGY

The co-infection of malaria parasites and helminths is common in the tropics. Their pathogenicity lies in the infectivity of parasites and their modulation of the host immune system. This study aimed to generate epidemiological data of malaria and helminths in apparently healthy humans in a rural population in Bayelsa State; determine the serum concentration of Interleukin-4, Interferon-gamma -IFN-γ, Macrophage Inflammatory protein-MIP-β/CCL-4 and Eotaxin-3 /CCL 26 in healthy volunteers infected with malaria and helminths and their values after treatment. Two sets of data; malaria and helminths were generated from school and community based study, carried out between May 2016 and July 2018 in four rural communities- Otuegela, Immiringi, Otuesega and Ibelebiri in which there was ongoing mass deworming and anti-malaria administration. Ethical approval was obtained from the Ethical Committee, College of Medicine, University of Benin, Nigeria (CMS/REC/2017/016). From every participant, blood and stool samples were collected; from 1441 volunteers, age-range 4 – 80 years. Diagnosis of helminths, malaria parasites were by standard procedures. The body mass index (BMI) of children was determined. Measurement of haemoglobin concentration and blood cells was automated (ABX Micros 60). Infected volunteers were treated specifically and after 18 days the second round of blood and stool samples were collected from treated participants only and analyzed. Immune molecules were measured by ELISA (PeproTech, USA) protocols. Data were analysed with the "R" Programme (version 2016) and a P-value of < 0.001 was considered significant.  The prevalence of helminths was: community-based, 26.0% and school children, 30.3%. Helminths identified in communities were Schistosoma intercalatum (10.4%), Schistosoma mansoni (4.2%), and a variant of Schistosoma intercalatum (0.2%); Ascaris lumbricodes (6.5%),), Trichuris trichiura (2.5%), hookworm (2.0%) and Taenia spp (0.2%). In school-based, Ascaris lumbricoides had 10.5%, Schistosoma mansoni 8.0 %, Schistosoma intercalatum 5.0% and Strongyloides 1.0% ; Trichuris trichiuria 1.8%, hookworm 1.6%, Taenia species 1.3%. In co-infection, 18.0% prevalence was obtained in the community and 10.5% in schools. The prevalence of malaria parasites in community study was 2742.0%. In a School-based study, the prevalence of malaria disease was 53.0% and 32.1% for first and second school-based study, respectively. Using Polymerase chain reaction (PCR) Plasmodium falciparum was identified at 205 bp and Plasmodium ovale at 787 bp. The mean values, before and after treatment for Eotaxin (5718pg/ml/ 5725pg/ml) and MIP-β (344.1pg/ml/642.6pg/ml) were close and had numerous outlines. The concentration of IFN-γ and IL-4 were higher in all categories of infection than after treatment but with no significant difference. IFN-γ had the highest mean expression (135.6pg/ml) in the coinfection group and least (59.8pg/ml) in the population infected by intestinal helminths only. The value for Plasmodium falciparum was 84.0pg/ml. Similarly, the expression of IL-4 was highest (68.8pg/ml) in co-infection and lowest (40.3 pg/ml) in helminths infected group. The value of IL-4 for those infected by Plasmodium falciparum only was 61.0pg/ml. There In all study groups, IFN-γ and IL-4 were positively correlated before and after treatment; which was significant (r = 0.60) in those infected by P. falciparum only. After treatment, the correlation between IFN-γ and IL-4 was significant in those who were treated for malaria infection (r = 0.7) and those who were treated for co-infection of P. falciparum and helminths (r = 0.6). There was a decrease in values of platelets, White Blood Cells and granulocytes during infection but platelet count was reduced after anthelminthic treatment and increased after anti-malaria administration. The ova of 7 species of helminths were diagnosed in this study. Treatment lowered the concentration of IFN-γ and IL-4 immune molecules in serum, which is of clinical relevance. This study proves that sub-clinical infection brought about a low concentration of IL-4/IFN-γ, altering their counter-inflammatory properties. They rather depended on each other positively. The clinical consequence of IL-4 suppression is the disability in class switch: antibody production is suppressed, resulting in susceptibility to infectious diseases. The presence of P.ovale in co-infection with P. falciparum is significant for the epidemiology and control of malaria disease in the Niger Delta.

A total of thirty (30) female Agama lizards were investigated to determine their diet. They were obtained from the Faculty of Life Sciences University of Benin, halls of residence and the University of Benin Food court. Specimens were collected between
the hours of 8-10am when they are not so active and easier to catch. The standard stomach flushing method was used in obtaining the contents of their stomach after which they were poured into a test tube with 10ml formalin added as preservative before it was taken for identification. A magnifying lens and microscope were used to identify micro and macro organisms respectively. Results from the investigation carried out shows the recorded prey categories in the stomach contents of Agama to be Orthoptera (n=13), Coleoptera (n=2), Diptera (n=38), Hymenoptera(n=17), Dictyoptera (n=3), Aranae (n=2) and Lepidoptera (n=1). The highest population was present in Diptera and lowest o in Lepidoptera. The results also showed high diversity in diptera which suggest that the Agama species is mainly insectivorous. Additional research needs to be carried out to further understand the in depth feeding habit of Agama in relation to seasons and how it helps them adjust to new habitats as this well help protect and conserve the Agama species in the ecosystem.

Antibiotics have been used in fish farms for the treatment of bacterial infections. The indiscriminate use of these antibiotics has however led to the issue of antibiotic residue in food animals, which has emerged globally as a public health risk. Lack of information on antibiotic residue in catfish (C. gariepinus) in developing countries such as Nigeria is however a major problem. This study was carried out to evaluate the concentration of tetracycline residues in catfish (C. gariepinus) from selected ponds in Edo Central, Edo State, Nigeria. Adult Catfish (C. gariepinus) samples were obtained from three ponds in Edo Central and analysed for tetracycline residue using the QuEChERS sample method for residue analysis. Questionnaires were also administered to catfish farmers to evaluate their antibiotic use and knowledge of antibiotic administration. The tetracycline residue present in catfish from the sampled ponds were above the maximum residue limits (MRL). Pond 1 had the highest mean tetracycline residue (1.87 ± 0.03 mg/kg) while Pond 2 had the lowest mean tetracycline residue of the sampled ponds (1.84 ± 0.05 mg/kg).

Pesticide contamination in aquatic organisms poses a growing concern for both food safety and environmental health. This study evaluated the effect of boiling on the residual levels of organochlorine and organophosphate pesticides in the African freshwater prawn (Macrobrachium vollenhovenii) obtained from markets in Benin City, Edo State, Nigeria. Prawn samples were collected from Uselu and Oba markets in August 2025. Pesticide residues were extracted and analysed using Gas Chromatography–Mass Spectrometry (GC–MS). Results showed that twenty (20) organochlorine and fourteen (14) organophosphate pesticide residues were detected in both raw and boiled prawn samples. The total concentration of organochlorines decreased from 28.42 ppb in raw samples to 23.845 ppb after boiling, indicating a slight reduction following heat treatment. Conversely, organophosphate pesticide levels increased from 8.595ppb in raw prawns to11.405ppb in boiled samples. Among organochlorines, α-HCH, β-HCH, PP‘-DDT were eliminated after boiling while Gamma-Chlordane, Alpha chlordane, PP‘-DDD, Methoxy For organophosphates, Chlorpyrifos (2.405 ppb) and Phosalone (1.58 ppb) showed notably higher levels of post-boiling, whereas Isazophos and Pyrazophos were completely degraded. For both pesticide groups, the estimated daily intake (EDI) for local consumers, based on an average prawn consumption rate of 0.33 kg/day and a 60 kg adult body weight for both the raw and boiled samples, were below the acceptable daily intake (ADI), indicating minimal potential health risks. Similarly, the hazard quotient (HQ) and hazard index (HI) values for both pesticide groups were less than one (<1) for both the raw and boiled samples, implying low non￾carcinogenic and carcinogenic risk to consumers. When compared with the FAO/WHO Codex and EU maximum residue limit (0.01 mg/kg for seafood), the total concentrations of organochlorine pesticides (0.028 mg/kg) exceeded the acceptable limit, indicating potential xiii xiv contamination risks. These findings suggest that while boiling can reduce certain persistent organochlorine residues, it may also increase the apparent concentration of some organophosphate pesticides. Continuous monitoring and further investigation into the effects of cooking methods on pesticide dynamics are recommended to safeguard consumer health.

Microplastics have become an emerging pollutant of concern in aquatic environments due to their persistence, potential toxicity, and ability to bioaccumulate in aquatic organisms. However, limited information exists on the extent of microplastics contamination in Nigerian freshwater systems, especially in the Ovia River. This study aims to assess microplastics contamination in surface water and some fish species (Notoptera's afar and Heterotriches BI dorsalis) of the Ovia River in Benin City, Nigeria, with the goal of determining pollution levels, potential sources, and associated health risks. Data were generated through the collection of water and fish samples from four stations along the river from January to June, 2024. Physicochemical parameters of the water were measured using standard procedures, and microplastics were extracted from both water and fish digestive tracts using density separation and wet peroxide oxidation methods. Polymer types were identified using Fourier Transform Infrared Spectroscopy (FTIR), while elemental composition was analyzed using Energy Dispersive X-ray Spectroscopy (EDX). Particle size distribution was examined using Scanning Electron Microscopy (SEM), and ImageJ software was used for image analysis. Pollution indices such as Water Quality Index (WQI), Contamination Factor (CF), and Carcinogenic and Non-carcinogenic Risk Indices (CDI, HQ, HI, CR) were also applied. The analysis of physicochemical parameters in the Ovia River revealed generally acceptable
levels with no significant differences (P > 0.05) across the study stations, except for copper, chromium, and manganese which showed significant variation (P < 0.05). Heavy metal concentrations were ranked: Fe > Zn > Cr > Cu >Mn > Ni > Pb, while arsenic and vanadium were below detection limits. Water Quality Index (WQI) and Comprehensive Pollution Index (CPI) classified Station 1 as having good water quality, while others were rated poor. Health risk assessment using Chronic Daily Intake (CDI) identified iron as the most prominent exposure risk. SEM revealed spatial variation in microplastic particle sizes in both water and fish, with the
highest mean sizes observed in station 2 and in Notoptera's afar respectively. Polymer analysis identified polyvinyl alcohol and nylon as the dominant microplastics in surface water, while LDPE (Low-density polyethylene) and polypropylene were most prevalent in fish samples. However, Heterotriches BI dorsalis exhibited a more diverse and complex microplastics polymer profile, indicating greater ingestion and exposure compared to Notoptera's afar. The xxii elemental composition in water and fish samples identified Cl, N, Na, C, Ca, Mg, Si, P, K, Al, Fe, S, Ti, Ag, and Mn as additives to microplastics with high intensity peaks of chlorine and carbon. Overall, the Ovia River ecosystem is moderately polluted with microplastics, and there is evidence of bioaccumulation in fish, necessitating urgent environmental management strategies. xxiv

The perception of insect pests management methods in rural areas of Badagry Local Government Area, Lagos State, Nigeria, is a critical aspect of sustainable agriculture and community well-being. This abstract provides a concise overview of a study conducted to understand the prevailing attitudes and beliefs of rural farmers towards insect pest management. In rural Badagry, agriculture plays a pivotal role in livelihoods, making insect pests a significant concern. This research employed a mixed-methods approach, combining surveys and interviews to gather data from farmers and agricultural extension officers. The findings reveal a complex perception landscape, where traditional and modern pest management methods coexist. Farmers, deeply rooted in tradition, often rely on indigenous knowledge and cultural practices. However, awareness of modern, science-based pest management approaches is increasing, thanks to the efforts of agricultural extension officers and outreach programs.Challenges such as limited access to resources, information gaps, and economic constraints affect the adoption of modern methods. Attitudes towards chemical pesticides are mixed due to concerns about environmental and health impacts. Furthermore, climate change is altering the pest landscape, necessitating adaptive strategies. This study underscores the importance of bridging the gap between traditional and modern insect pest management practices. It advocates for holistic, context-specific interventions that consider local knowledge while promoting sustainable, science-based approaches. Such initiatives can enhance food security, reduce pesticide risks, and support the resilience of rural communities in Badagry and similar regions.