DEPARTMENT OF ANIMAL AND ENVIRONMENTAL BIOLOGY

Zooplankton constitute a diverse assemblage in most freshwater habitats. A study on the assessment of physico-chemical Characteristics in relation to zooplankton communities in fresh water habitats in Oghara, Delta State was conducted from January – March 2021. Water and Zooplankton samples were collected at monthly and fortnightly respectively at three different sampling stations. Physicochemical parameter were determined using standard methods while Zooplankton Samples were preserved with 4% formaldehyde solution. Mean temperature ranged from (26.00 ±0.577 - 28.83 ± 1.589). Mean Value of Ph was slightly acidic to neutral, ranging from (6.76 – 6.05). Dissolved Oxygen was quite low typical of most eutrophic water bodies. BOD mean value was relatively high (5.80 – 8.40) owing to
increased organic decomposition by organisms during the study period. Nitrate ranged from (0.57 to 5.27) during the study period. The result of zooplankton composition indicated the presence of 33 species of Zooplanktons belonging to three major classes; Cladocera 1108 individual taxa (93.5%), Rotifera 5 individual taxa (0.43%) and Copepoda 72 individual taxa (6.07%). Cladocera were more diverse with 21 representative species, followed by Copepods and Rotifers with 9 and 3 species respectively

A parasite is a living organism that lives inside or on another living organism, the host upon which it relies on for the resources necessary for its survival. A parasite depends on the host for its growth and reproduction. This study was conducted to investigate the prevalence of parasitic contamination in fruits from Efehi Street, New Benin Market and how the location affects it. The fruits examined were Cucumber (Cucumis sativus), Carrot (Daucus carota), African pear (Dacryodes edulis), and Garden egg (Solanum aethiopicum). The overall prevalence of parasitic contamination recorded in this study was 91.7%. Parasitic contamination was highest in Cucumber (Cucumis sativus) with Overall prevalence of 96.7% while the least contaminated was African Pear with prevalence of 86.7%. The parasites recovered from the fruits were Ascaris lumbricoides, Strongyloides stercoralis, Trichuris trichiura, Enterobius vermicularis, Ancylostoma duodenale, Trichostrongylus sp., Taenia sp., Heterophyes heterphyes, Entamoeba sp., Toxoplasma gondii, Giardia intestinalis, Balantidium coli, Unidentified nematode larvae and unidentified nematode egg. Ascaris lumbricoides was the most prevalent parasite and it was recovered from 60% of the samples. Most fruit samples got contaminated due to the unhygienic means of storage and transportation

The presence of pesticide residues in aquatic organisms has become a growing public health concern due to the extensive use of agrochemicals and their potential to contaminate water bodies and aquatic food resources. This study focused on the determination of pesticide residues in the African freshwater prawn, Macrobrachium vollenhovenii, obtained from Oba Market. The aim was to assess the levels of pesticide contamination and evaluate potential risks associated with human consumption. Fresh prawn samples were randomly collected from different vendors in the market and transported to the laboratory for analysis. The samples were processed, extracted, and analyzed for selected pesticide residues using standard analytical techniques such as Gas Chromatography (GC) following appropriate extraction and clean-up procedures. The results revealed the presence of various pesticide residues, including organochlorine, organophosphate, and pyrethroid compounds, in varying concentrations within the prawn tissues. Some detected residues were found to be within permissible limits established by international regulatory agencies, while others approached or slightly exceeded recommended thresholds. The occurrence of these residues indicates possible environmental contamination of aquatic habitats resulting from agricultural runoff, improper pesticide disposal, and other anthropogenic activities. The study highlights the need for continuous monitoring of pesticide residues in aquatic food products sold in local markets to ensure food safety and protect public health. It also emphasizes the importance of implementing stricter regulations and promoting environmentally sustainable agricultural practices to minimize pesticide pollution in aquatic ecosystems. The findings provide useful baseline information for policymakers, environmental agencies, and public health authorities regarding pesticide contamination in seafood consumed in Benin City.

The increasing degree of heavy metals contamination requires proper and effective health management on the ecological well-being by probing water, soil and fauna species within the environment .This study was carried out to investigate the distribution of heavy metal concentrations, specifically Lead (Pb) and Copper (Cu) in soil, water and in selected amphibian species across selected sites in Benin City, Edo State. Amphibians species (Sclerophrys regularis, Sclerophrys maculata, Afixalus dorsalis, Ptychadena longirostris, Ptychadena oxyrhynchus, Hypercolius fusciventris, Ptychadena mascareniensis, Ptychadena pumilio, Hoplobatrachus occipitalis, Ptychadena bibroni) were collected from four sampling sites (Iguosa river, Oluku dumpsite, Life science vicinity and Ikpoba river) between June and July 2023 . Heavy metal concentrations were analyzed using the Atomic Absorption Spectroscopy (A.A.S) The concentration of Pb in Iguosa and Ikpoba rivers were below the permissible limit of World Health Organization (WHO). At Iguosa river, Pb was 0.011mg/kg and Cu 1.445mg/kg, while at Ikpoba river Pb 0.006mg/kg and Cu 0.284mg/kg, both below the WHO permissible limit. The concentrations of Pb and Cu in soils from the sites were all below the European Union. The accumulation pattern was Ikpoba River> Iguosa River > Oluku Dumpsite > Life Science Vicinity (University of Benin) for Pb and Cu in amphibian toe snip samples. Hence, these heavy metal concentrations have no immediate threat on the health of water, soil quality and public health.

This study was carried out to investigate the parasites of the shrimp Panaeus monodon collected from Iguoriakhi River, near Benin City in Ovia North East Local Government Area located between Longitude 005 °25’55.0 - 005 °29’36.20E and Latitude 06 °23’42.76N - 06 °27’10.15N. Live shrimps were collected from
November 2021 to February 2022. A total of 101 shrimps were examined, out of which 49(48.5%) were infected with parasites. A total of 59 trematode metacercaria
were extracted from infected shrimps with overall mean intensity of 1.20±0.00. Shrimps examined in February had the highest parasite prevalence of 100 %. The
results also revealed that pasitic prevalence increased in shrimps as their sizes increased, however a drastic decline was observed in larger shrimps with length
between 711.5 - 15.49. Shrimps with length between 7.5-9.49 had the highest revalence with an overall mean intensity of 1.03±0.00. The results of this study
suggest that the black tiger shrimp is susceptible to parasites that can cause health complications when consumed. Therefore care should be taken to avoid human
infection.

Houseflies, also known as Musca domestica L. , are a type of insect in the Muscidae family. Certain types of these bugs are capable of transmitting illnesses. They are called dirty flies because they like to hang around things like garbage and poop. This study found the germs and harmful bacteria that are linked to house flies and the potential danger in the main market in Egor Local Government Area of Edo state. We used a net to collect things from two parts of the dumpsites.Testing was done on housefly samples to find out what kind of bacteria were in them. This involved looking at the bacteria under a microscope, identifying their physical traits, and seeing how they grew on special substances. The studyfound certain types ofbacteria, including Escherichia coli, Pseudomonas aeruginosa, Serratia marcescens, and Proteus vulgaris. The study found that the amounts of certain types of bacteria ranged from 1. 4 x 106 to 1. 6 x 106 for coliformbacteriaandfrom6.7x106to7.4x106forotherbacteria.
The bacteria Escherichia coli, Serratia, Pseudomonas, and Proteus were separated. We all react strongly to Gentamycin and ciprofloxacin. is a type of bacteria. E coli and Serratia bacteria are easily affected by chitosan. is a type of bacteria. The tests showed that most bacteria were sensitive to carbenicillin, but Proteus sp was resistant to it. The MAR index ranged from 0. 333 to 0444. It was found that houseflies in Uselu market from Egor Local Government Area of Edo state carry harmful parasites and bacteria on their bodies and inside them. So there is need to control the number of flies to prevent diseases caused by flies now and in the future..

The study was carried out to investigate the parasite of the freshwater snail Pilaovata .A total of 30 samples were collected from Ovia River at Iguoriakhifor a period of 4 months from October to January. The snails were transported to the Parasitology Laboratory, Faculty of Life Sciences, University of Benin, Benin City, Edo State, Nigeria for examination. Of the 30 snail samples collected, 4 were
naturally infected giving a prevalence of 13.3% only. The observation in this study is that the parasites found in the snails were the trematode larval stages (sporocysts). A
total of8 parasites (sporocysts) were recovered from 3 specimens of Pilaovata which were observed in the month of October 2021giving a mean intensity of2.7±1.5 and 3
parasites (sporocysts) were recovered from 1 infected snail giving a mean intensity of 3±0.00 in the month of November. However, no infection was recorded in the months
of December and January. The sporocysts were mostly found in the intestine,muscle and mantle regions of pilaovata. It can be concluded that Pilaovata serves as an intermediate host of this yet to be identified trematode sincethey harbor the
intramolluscanstage (sporocyst) of the parasite. Further studies should be carried out to identify the other stages of this trematode occurring in Pilaovatain Nigeria, and to
ascertain the possible zoonotic status of the parasite.

This study examined the length-weight relationship, Fulton's k-factor, and sex ratios of Chromidotilapia guentheri and Malapterurus electricus from October 2023 to March 2024. The study was carried out in Ikpoba River, Benin City. The Overall mean values for total length (TL), standard length (SL), head length (HL), body depth (BD), weight, and k-factor for Chromidotilapia guentheri during the sampling period were 26.0cm, 20.3cm, 7.1cm, 8.2cm,106.4g, and 3.8725, respectively. The Overall mean values for TL, SL, HL, BD, weight, and k-factor Malapterurus electricus during the sampling period were 32.9cm, 28.0cm, 8.5cm, 5.3cm, 139.2g, and 4.5710, respectively. The sex ratios of C. guentheri were 0.4:0.6, indicating a higher number of females, M. electricus were 1:00.8, indicating a higher number of males. C. guentheri had a mean k-factor ranging from lower than 1.61 in November to higher than 2.26 in March, while M. electricus ranged from lower than 0.94 in January to higher than 10.4 in March. The regression coefficients were less than 3 (b<3) for both species, indicating a negative allometric growth, meaning that the fish become slimmer/less weighty with increasing. The knowledge of these species is important for proper management of fishery resources and increase knowledge on understanding the species and other related fish.

A two month investigation was conducted to study the helminth parasites of geckos from Uhogua, in Ovia North-East Local Government Area of Edo State, Nigeria. This study was aimed at determination of the gecko diversity found in Uhongua community in Benin City, Edo state, as well as the helminth parasites they habour. A total of 23 geckos which were of two species; Hemidactylus angulatus and Hemidactylus mabouia were examined. They consisted of 17 males, 4 females and 2 juvenile. The geckos were randomly collected at night from a poultry farm situated close to a residential building by hand, after which they were transported to the laboratory where they were euthanized, dissected and examined for parasites. The following parasites were encountered during this study; one pentastomid; aillietiella affinis, one cestode; Oochoristica sp., one trematode; Mesocoelium sp., and three species of nematodes namely; Strongyluris brevicaudata, Parapharyngodon awokoyai, and
Thelandros scleratus. The most encountered parasite in this study was T. scleratus having an overall prevalence of 47.83% and a mean value of 1.75, while S. brevicaudata was least
encountered, with an overall prevalence and mean value of 4.34% and 1.00 parasite per infected host respectively. A

A one month (August, 2023) study was conducted in Okomu Oil Palm plantation (an altered rainforest habitat) located in Ovia South-West L.G.A., Edo state Nigeria in order to investigate the dietary and feeding habit of the ground dwelling anurans in the study area. The paucity in available information on the food and feeding habit of ground dwelling anurans from the rainforest ecological zone necessitated this study. The specimens were collected at night using the visual and acoustic sampling technique. They were euthanized by exposure to chloroform in a killing jar, injected and fixed with 10% formalin to arrest digestion and preserve stomach content. The gut contents were introduced into properly labeled vials and their prey items fixed in 70% alcohol for microscopic examination and identification. The dietary composition of 28 ground dwelling anurans belonging to 3 families (Bufonidae, Pipidae and Ranidae), 4 genera (Sclerophrys, Silurana, Ptychadena and Hoplobatrachus) and 5 species were recorded. The species encountered included: Sclerophrys maculata, Silurana tropicalis, Hoplobatrachus occipitalis, Ptychadena bibroni and Ptychadena longirostris. A total of 325 prey items belonging to 8 Orders, were recovered from their stomach of which Hymenoptera had the highest abundance of 92.9%, was the most dominant prey item recorded while the least prey item recorded were Dermaptera, Orthoptera and Geophilomorpha which had the lowest abundance of 0.31% each.