This study investigated fish parasites in relation to limnological variables of the Esa-Odo reservoir since the quality of the aquatic environment might influence parasitic infestation in fish. The purpose of this study was to provide information on the parasite species of the reservoir due to their public health concern and their relationship with selected water quality parameters. The water quality and parasite examinations were analyzed based on standard protocols in the laboratory. The results showed that water quality parameters were not significantly different (p > 0.05) across the zones. Seasonally, mean water temperature, pH, TDS, DO, organic matter, COD and turbidity were significantly different (p < 0.05) across the different zones of the reservoir while electrical conductivity, alkalinity, NO3-, and PO43- were not significantly different (p > 0.05). Clinostomum tilapiae, Clinostomum sp., Euclinostomum heterostomum, Procamallanus laevionchus, and Lytocestus sp. were recovered in all the fish sampled. The overall prevalence of the fish parasites was 9.8% with an intensity of 2.13. The result indicated fish parasites had a strong positive correlation with certain water quality properties and parasite abundance which suggested that water quality could determine parasitic loads in fishes of the Esa-Odo reservoir.

  • The study provided the first record of an additional fish parasite in the Esa-Odo reservoir fish community.

  • It also pinpoints the relationship between fish parasites and selected water quality.

  • The selected limnological variables determine the abundance of fish parasites.

  • This study will assist in further research of parasite vectors in the reservoir.

  • It will encourage proper monitoring of the fisheries resources of the reservoir.

Graphical Abstract

Graphical Abstract
Graphical Abstract

Fish parasites have been a major concern for freshwater and marine fish all over the world and are of particular significance in the tropical region (Ekanem et al. 2011). The examination of fish species for the presence of parasites is a critical aspect of maintaining the sustainability of capture fisheries. This is due to the negative impacts that parasites can have on fish health, including increased susceptibility to diseases, reduced nutrition, and mortality (Onyedineke et al. 2010). To effectively support wild fish production, it is necessary to regularly assess fish for the presence of parasites. This practice can help to mitigate the negative impacts of parasites on fish populations and support the overall health and sustainability of capture fisheries. Thereby, serving as an indicator that the fish is healthy for consumption. In addition to the negative effects they can have on fish populations, parasites can also serve as environmental indicators to monitor the quality of aquatic environments (Dzika & Wyżlic 2011; Palm 2011; Unger et al. 2014). Limnological variables such as pH, temperature, dissolved oxygen content, and alkalinity, as well as parasitological factors such as parasite prevalence, mean intensity, and mean abundance that indicate a direct relationship between water quality and parasitic infection or fish susceptibility to parasitic infection (Biswas & Pramanik 2016). Water quality is evaluated based on various physical, chemical, and biological characteristics that can affect the suitability of aquatic environments for fish and other aquatic organisms. These characteristics include factors such as temperature, pH, dissolved oxygen levels, and the presence of pollutants or pathogens. Understanding these factors helps to determine the distribution and production of aquatic life (Yerima et al. 2017).

Fish could serve as intermediate or final hosts of parasites that are dangerous to man and animals (Okoye et al. 2014). Fish parasites could also serve as possible biomarkers for ecology and trophic interactions (Cauyan et al. 2013). High-quality fish species that are free from parasites or microbial infection are required to sustain the ever-increasing fisheries production (Abdullahi et al. 2017). Hence, the role of freshwater fish in spreading parasites to man had been acknowledged for a long period of time (Omeji et al. 2011; Khalil et al. 2014; Ali & Faruk 2018). A study conducted on some freshwater fish in Warri River, Nigeria revealed that the highest parasite prevalence was observed in Synodontis clarias, while the least prevalence was recorded in Coptodon zillii with overall parasite prevalence recorded in the metazoan (Ejere et al. 2014). In the lower Benue River, both Clarias gariepinus (29.33%) and Clarias anguillaris (27.33%) had higher parasite prevalence during the dry season than during the wet season (Uruku & Adikwu 2017).

When the community composition or demographic distribution of hosts or parasites changes, the interaction between hosts and parasites and the ecological conditions changes (Buser et al. 2012; Scharsack et al. 2012; Budria & Candolin 2014). Water quality changes can impact both host immunity and defensive systems, as well as the transmission pathways of parasites, leading to alterations in the host-parasite relationship (Lazzaro & Little 2009; Kutzer & Armitage 2016). Declines in the abundance of some monogenean parasites have been observed in association with the deterioration of water quality and decreased dissolved oxygen levels (Zargar et al. 2012). Several ectoparasite species, including trichodinids, have been shown to proliferate in the presence of low dissolved oxygen levels (Carol et al. 2006).

The prevalence and distribution of parasite species are influenced by temperature, rising temperatures increase the pathogenicity and infection rates of parasites (Kutz et al. 2005; Larsen & Mouritsen 2014).

Moreover, research has consistently shown that parasitic infections and diseases are among the factors that lead to a reduction in fish production (Dougnon et al. 2012). Parasites are well-known to act as pathogens, causing direct death or rendering the fish more susceptible to predators (Kunz & Pung 2004). Although, helminths parasite of Oreochromis niloticus and C. gariepinus and phytoplankton composition in the reservoir has been documented (Ibironke & Morenikeji 2018; Isichei et al. 2020). This study aimed to assess the relationship between fish parasite abundance and water quality parameters in the Esa-Odo reservoir, where no previous records of limnological variables as determinants of fish parasites’ abundance exist. The abundance of fish parasites and water quality parameters were analyzed to determine the level of parasitization in the reservoir. This provided background information on the different parasites recovered and water quality influence on the parasite abundance. This study evaluated the relationship between fish parasite abundance and water quality in the Esa-Odo reservoir by comparing the abundance of parasites with water variables. It has been shown that different limnological variables have impacts on the composition of parasites in fish species (Galli et al. 2001; Georges et al. 2020; Waruiru et al. 2021).

The specific objectives of the study were to:

  • determine limnological variables of the reservoir,

  • assess the parasitic infestation in terms of prevalence and intensity, and

  • correlate limnological variables with parasites’ abundance of the reservoir.

Study area

The investigated water body was the Esa-Odo reservoir which is one of the largest surface water bodies in Osun State (Figure 1). The reservoir had a surface area of 50.2 ha when it was initially impounded but has reduced over time as a result of vegetation covering parts of the reservoir (Isichei et al. 2020). The reservoir supplies potable water to the entire Obokun local government area, and provides potential for fishery enterprise as well as for tourism and raw water for industrial use at the International Breweries, Ilesa, Nigeria. Esa-Odo lies approximately on Latitude 007°45′0′ N to 007°47′18′ N and Longitude 04°49′0′ E to 04°50′12′ on an elevation of 458 m above sea level. The area is under the Koppens Humid Tropical climate type with a short dry season (November–February) and a rainy season (March–October) with bimodal rainfall distribution. The mean annual rainfall is approximately 1,500 mm. The sampling was carried out between October 2018 and September 2019. Standardized pH buffer solutions were used to determine the pH of the water. Total dissolved solids and electrical conductivity were analyzed using TDS meter (PCE-PHD Version 1.1 Model Q656697) and Conductivity Bridge (PCE-PHD Version 1.1 Model Q656697), respectively. Water samples for dissolved oxygen were collected in 250 mL of Amber bottles and fixed in situ using Winkler's reagents. Similarly, water samples for biological oxygen demand (BOD5) determination were collected in dark amber bottles and kept in the dark cupboard for a period of 5 days and Winkler's reagents were used after the incubation period (APHA 1999). The following physico-chemical parameters were determined in the laboratory using appropriate titrimetric and instrumentation methods as described by American Public Health Association (APHA): DO, BOD5, nitrates, phosphates, turbidity, alkalinity, acidity, chemical oxygen demand, total organic carbon. To ensure the accuracy of the analysis, quality assurance, and quality control were strictly observed.
Figure 1

(a) Map of Nigeria showing Osun State, (b) map of Osun State showing local government area, (c) map of Obokun local government, and (d) map of the Esa-Odo reservoir.

Figure 1

(a) Map of Nigeria showing Osun State, (b) map of Osun State showing local government area, (c) map of Obokun local government, and (d) map of the Esa-Odo reservoir.

Close modal

Fish sampling

Fish samples were collected on a monthly basis for an annual season using gill nets, casts net and traps with the help of fishermen. The services of fishermen operating on the reservoir were employed for the setting of fishing gear. Fish species were caught with traps, gears, and cast netting. Gill nets of 20 mm mesh size were used to collect fish. Cast nets of 22 mm were also used. The fishing nets were set at different locations on the reservoir covering the upstream, midstream and downstream. All the fish samples were brought to the laboratory of the Zoology Department at Obafemi Awolowo University, Ile-Ife in an icebox for further analysis. The fishes were identified using standard keys (Paugy et al. 2003) while the total and standard lengths of the fish were taken using meter-rule in centimeters.

Examination of fish for parasites

Each fish sample was dissected to remove the gills, scales, esophagus, stomach, eggs, liver, and intestines. The organs were examined for parasites. The external body parts were picked by forceps and placed into a Petri dish. Also, the abdomen was dissected and divided into the stomach and intestine. Each segment was slit open, isolated, and placed into Petri dishes containing physiological saline (0.9% NaCl). The isolated segments from the petri dish were examined for the presence of parasites under a dissecting microscope on a black surface for clear visibility.

Collection and preservation of parasites

Parasites recovered from each segment were properly washed and fixed in 70% ethanol as described, location of infection was noted (Olurin & Somorin 2006).

Staining and examination of parasites

The parasites were removed from the preservative (70% alcohol), stained in acetic hematoxylin for 10 min and destained in acid alcohol. Subsequently, they were differentiated in 45% acetic acid and transferred into glacial acetic acid for 10–15 min for dehydration. The dehydrated parasites were cleared in the ratio 3:1, 1:1, 1:3 series of a mixture of glacial acetic acid and methyl salicylate. The parasites were then mounted in Canada balsam on a clean and clear glass slide and examined under the microscope (Oniye et al. 2004). Measurement of the worms and their internal organs was done using a digital binocular compound LED microscope (model MD827S30L series).

Identification of parasites

Each parasite species were identified to the least possible taxon and were based on the descriptions and identification keys prepared by Yamaguti (1958) and Paperna (1996), and their microphotographs were taken using a digital binocular compound LED microscope (model MD827S30L series).

Statistical analysis

The data collected for fish were analyzed using descriptive statistics which include frequency tables, means, standard deviation, and percentages as appropriate. The relationships between water quality and parasite composition of fish species were determined using a correlation coefficient matrix. Data for water analysis were subjected to appropriate statistical methods such as descriptive statistics, t-test, and analysis of variance (ANOVA) using SPSS version 24. The prevalence, intensity, and mean intensity were evaluated according to Margolis et al. (1982) and Busht et al. (1997). Inter-correlation between physico-chemical parameters was determined using PAST (Paleontological Statistics) Statistical software version 2.12.

Ethical approval

This study was approved by the committee on animal experiments in the Department of Zoology, Obafemi Awolowo University, Ile-Ife. All the experimental guidelines involving fish were carried out by standard procedures.

Limnological variables

The limnological parameters of water samples collected at different zone of the reservoir is as shown in Table 1. The highest mean water temperature was recorded at the riverine (26.1 ± 0.64°C) and there was a significant difference (p < 0.05) among the reservoir zones. The overall pH of the reservoir was 7.15 ± 0.20 while the highest mean pH was observed at the transition zone (7.16 ± 0.14) and the lowest value was recorded at the dam site (7.14 ± 0.13). The highest mean concentration of conductivity and TDS was recorded at the transition zone 121 ± 6.82 μS/cm and 80.4 ± 7.10 mg/L, respectively. There was no significant difference (p > 0.05) in the mean values of dissolved oxygen across the reservoir zones. Also, the highest mean value of alkalinity was obtained at the riverine zone (43.6 ± 7.68 mg/L) while the lowest value was observed at the transition zone (42.3 ± 7.78 mg/L). The maximum mean concentrations of nitrate and phosphate were recorded at the transition zone (1.57 ± 0.47 mg/L) and 1.45 ± 0.72 mg/L at the dam site, respectively. There was no significant difference (p > 0.05) in the mean values of organic matter among the various zones of the reservoir. The overall COD of the reservoir was 14.5 ± 4.47 mg/L while the highest mean COD was observed at the transition zone (15.3 ± 5.22 mg/L) and the lowest value was recorded at the dam site (13.6 ± 3.91 mg/L). The highest mean concentration of turbidity was recorded in the dam site (95.9 ± 31.03 mg//L) and there was no significant difference (p > 0.05) between the mean value of turbidity observed across the zone of the reservoir.

Table 1

Overall limnological variables of water sampled across the zones

ParametersZones
Overall Mean ± S.D.F-ratiop-value
Dam siteTransitionRiverine
Mean ± S.D.Mean ± S.D.Mean ± S.D.
Water temp. (°C) 25.4 ± 0.58a 25.8 ± 0.80a 26.1 ± 0.64a 25.7 ± 0.72 3.20 0.05 
pH 7.14 ± 0.13a 7.16 ± 0.14a 7.15 ± 0.91a 7.15 ± 0.20 0.06 0.94 
Electrical conductivity (μS/cm) 118 ± 7.44a 121 ± 6.82a 120 ± 7.75a 120 ± 7.24 0.51 0.61 
Total dissolved solid (mg/L) 79 ± 5.96a 80.4 ± 7.10a 80.2 ± 6.93a 79.8 ± 6.52 0.16 0.85 
Dissolved oxygen (mg/L) 5.12 ± 1.77a 5.20 ± 1.72a 5.42 ± 1.47a 5.25 ± 1.61 0.10 0.90 
Alkalinity (CaCO3mg/L) 42.5 ± 6.33a 42.3 ± 7.78a 43.6 ± 7.68a 42.4 ± 7.14 0.25 0.78 
Nitrate (mg/L) 1.34 ± 0.50a 1.57 ± 0.47a 1.54 ± 0.56a 1.49 ± 0.51 0.66 0.52 
Phosphate (mg/L) 1.45 ± 0.72a 1.41 ± 0.63a 1.03 ± 0.38a 1.30 ± 0.61 1.84 0.18 
Organic matter (mg/L) 9.52 ± 2.74a 10.3 ± 3.09a 10.7 ± 3.14a 10.2 ± 3.14 0.44 0.65 
Chemical oxygen demand (mg/L) 13.6 ± 3.91a 14.6 ± 4.40a 15.3 ± 5.22a 14.5 ± 4.47 0.44 0.65 
Turbidity (NTU) 95.9 ± 31.03a 93.8 ± 30.6a 92 ± 30.5a 93.9 ± 29.9 0.05 0.95 
ParametersZones
Overall Mean ± S.D.F-ratiop-value
Dam siteTransitionRiverine
Mean ± S.D.Mean ± S.D.Mean ± S.D.
Water temp. (°C) 25.4 ± 0.58a 25.8 ± 0.80a 26.1 ± 0.64a 25.7 ± 0.72 3.20 0.05 
pH 7.14 ± 0.13a 7.16 ± 0.14a 7.15 ± 0.91a 7.15 ± 0.20 0.06 0.94 
Electrical conductivity (μS/cm) 118 ± 7.44a 121 ± 6.82a 120 ± 7.75a 120 ± 7.24 0.51 0.61 
Total dissolved solid (mg/L) 79 ± 5.96a 80.4 ± 7.10a 80.2 ± 6.93a 79.8 ± 6.52 0.16 0.85 
Dissolved oxygen (mg/L) 5.12 ± 1.77a 5.20 ± 1.72a 5.42 ± 1.47a 5.25 ± 1.61 0.10 0.90 
Alkalinity (CaCO3mg/L) 42.5 ± 6.33a 42.3 ± 7.78a 43.6 ± 7.68a 42.4 ± 7.14 0.25 0.78 
Nitrate (mg/L) 1.34 ± 0.50a 1.57 ± 0.47a 1.54 ± 0.56a 1.49 ± 0.51 0.66 0.52 
Phosphate (mg/L) 1.45 ± 0.72a 1.41 ± 0.63a 1.03 ± 0.38a 1.30 ± 0.61 1.84 0.18 
Organic matter (mg/L) 9.52 ± 2.74a 10.3 ± 3.09a 10.7 ± 3.14a 10.2 ± 3.14 0.44 0.65 
Chemical oxygen demand (mg/L) 13.6 ± 3.91a 14.6 ± 4.40a 15.3 ± 5.22a 14.5 ± 4.47 0.44 0.65 
Turbidity (NTU) 95.9 ± 31.03a 93.8 ± 30.6a 92 ± 30.5a 93.9 ± 29.9 0.05 0.95 

Note: row mean scores with same superscript (a,b) are not significantly different (p > 0.05) from each other.

Seasonally, the highest water temperature was recorded in the dry season (28 ± 0.10 °C) when compared with the rainy season (25.4 ± 0.89°C) as shown in Table 2. The mean values recorded for pH were higher during the dry season (7.22 ± 0.09) than the rainy season (7.10 ± 0.12). High mean concentrations of conductivity (121 ± 2.24) μS/cm and TDS (82.2 ± 1.17 mg/L) were recorded in the dry season. Also, there was a significant difference (p < 0.05) in the dissolved oxygen of water samples across the seasons. The alkalinity mean concentration was higher in the rainy season than in the dry season (Table 2). The highest mean concentration of nitrate was recorded during the rainy season (1.53 ± 0.11 mg/L) whereas the dry season was recorded to have the highest mean value of phosphate (1.31 ± 0.21 mg/L). Mean values recorded for organic matter and COD were higher during the dry season than during the rainy season. A high mean turbidity value of 115 ± 4.13 mg/L was recorded in the rainy season when compared to the dry season which obtained a mean value of 65.1 ± 3.57 mg/L (Table 2).

Table 2

Seasonal limnological variables of water sampled

ParameterRainy seasonDry seasontp-value
Mean ± S.E.Mean ± S.E.
Water temp. (°C) 25.4 ± 0.89 28 ± 0.10 2.21 0.04* 
pH 7.10 ± 0.12 7.22 ± 0.09 −3.25 0.00* 
Electrical conductivity (μS/cm) 119 ± 1.33 121 ± 2.24 −0.83 0.42 
Total dissolved solid (mg/L) 78.2 ± 1.58 82.2 ± 1.17 −2.07 0.05* 
Dissolved oxygen (mg/L) 4.75 ± 0.32 5.94 ± 0.42 −2.26 0.03* 
Alkalinity (CaCO3mg/L) 44 ± 1.48 40.3 ± 1.87 1.56 0.12 
Nitrate (mg/L) 1.53 ± 0.11 1.43 ± 0.14 0.59 0.58 
Phosphate (mg/L) 1.29 ± 0.01 1.31 ± 0.21 0.57 0.58 
Organic matter (mg/L) 9.03 ± 0.69 11.8 ± 0.62 −2.95 0.00* 
Chemical oxygen demand (mg/L) 12.9 ± 0.98 16.8 ± 0.88 −2.30 0.00* 
Turbidity (NTU) 115 ± 4.13 65.1 ± 3.57 9.06 0.00* 
ParameterRainy seasonDry seasontp-value
Mean ± S.E.Mean ± S.E.
Water temp. (°C) 25.4 ± 0.89 28 ± 0.10 2.21 0.04* 
pH 7.10 ± 0.12 7.22 ± 0.09 −3.25 0.00* 
Electrical conductivity (μS/cm) 119 ± 1.33 121 ± 2.24 −0.83 0.42 
Total dissolved solid (mg/L) 78.2 ± 1.58 82.2 ± 1.17 −2.07 0.05* 
Dissolved oxygen (mg/L) 4.75 ± 0.32 5.94 ± 0.42 −2.26 0.03* 
Alkalinity (CaCO3mg/L) 44 ± 1.48 40.3 ± 1.87 1.56 0.12 
Nitrate (mg/L) 1.53 ± 0.11 1.43 ± 0.14 0.59 0.58 
Phosphate (mg/L) 1.29 ± 0.01 1.31 ± 0.21 0.57 0.58 
Organic matter (mg/L) 9.03 ± 0.69 11.8 ± 0.62 −2.95 0.00* 
Chemical oxygen demand (mg/L) 12.9 ± 0.98 16.8 ± 0.88 −2.30 0.00* 
Turbidity (NTU) 115 ± 4.13 65.1 ± 3.57 9.06 0.00* 

Note: *p < 0.05 based on seasonal variation with respect to Student t-test.

Fish morphometric, parasites and correlates of limnological variables with respect to fish parasites

The total length of O. niloticus recorded in this study ranged between 12.9 and 37.5 cm with a mean standard length of 17 cm and weight of 212 g (Table 3). The mean total length of 23.6 cm was recorded for P. obscura with a standard length that varied from 13 to 32.9 cm and a fish weight of 140 g. In the same vein, the total length of C. gariepinus varied widely from 19.5 to 35.1 cm with a standard length mean value of 21.6 cm and mean weight of 183 g. Marcusenius senegalensis had mean total and standard lengths of 16.9 and 14.8 cm, respectively, with a weight that ranged between 26 and 278 g. The total length of Hepsetus odoe recorded ranged between 13.1 and 36.5 cm with a mean standard length of 18.4 cm and a mean weight of 212 g. The morphometric measurements of Ctenopoma kingsleyae with respect to the mean total length, standard length and weight were 13.6, 11.2, and 53 g, respectively.

Table 3

Length (cm) and weight (g) of fish species

Fish speciesTotal length (cm)
Standard length (cm)
Weight (g)
Min–MaxMean ± S.D.Min–MaxMean ± S.D.Min–MaxMean ± S.D.
Oreochromis niloticus 12.9–37.5 21.1 ± 4.9 10.4–31.5 17 ± 4.4 32–1,220 212 ± 167 
Parachanna obscura 16–37.1 23.6 ± 4.2 13–32.9 21.1 ± 3.9 44–486 140 ± 86 
Clarias gariepinus 19.5–35.1 25.5 ± 3.5 16–30.6 21.6 ± 3 74–454 183 ± 65 
Marcusenius senegalensis 12.4–27.8 16.9 ± 2.7 10.9–22.8 14.8 ± 2.3 26–278 73 ± 44 
Hepsetus odoe 13.1–36.5 22.1 ± 6 10.7–31 18.4 ± 5.1 46–592 133 ± 39 
Ctenopoma kingsleyae 10.3–18.3 13.6 ± 2.3 8.5–15 11.2 ± 2 26–120 53 ± 28 
Fish speciesTotal length (cm)
Standard length (cm)
Weight (g)
Min–MaxMean ± S.D.Min–MaxMean ± S.D.Min–MaxMean ± S.D.
Oreochromis niloticus 12.9–37.5 21.1 ± 4.9 10.4–31.5 17 ± 4.4 32–1,220 212 ± 167 
Parachanna obscura 16–37.1 23.6 ± 4.2 13–32.9 21.1 ± 3.9 44–486 140 ± 86 
Clarias gariepinus 19.5–35.1 25.5 ± 3.5 16–30.6 21.6 ± 3 74–454 183 ± 65 
Marcusenius senegalensis 12.4–27.8 16.9 ± 2.7 10.9–22.8 14.8 ± 2.3 26–278 73 ± 44 
Hepsetus odoe 13.1–36.5 22.1 ± 6 10.7–31 18.4 ± 5.1 46–592 133 ± 39 
Ctenopoma kingsleyae 10.3–18.3 13.6 ± 2.3 8.5–15 11.2 ± 2 26–120 53 ± 28 

Five (5) different fish parasite species with a total number of 114 individual parasites belonging to three classes were recovered among 540 fish samples during the sampling period (Table 4). Fish species were infected with various species of parasites at different parts such as gills, liver, gill cover, intestine, stomach, body cavity, and the eye. Parasites encountered include: Clinostomum tilapiae, Clinostomum sp., Euclinostomum heterostomum, Procamallanus laevionchus and Lytocestus sp. The highest prevalence and mean intensity during this study were 9.81% and 2.15, respectively. Across the fish species, the highest prevalence was recorded in C. kinsglayae with prevalence rate of 47.6 and was infested with Clinostomum sp. while the least prevalence rate was recorded in C. gariepinus with prevalence rate of 0.91% and E. heterostomum was the recovered parasite. The mean intensity of the parasite varied from parasite to parasite with a maximum mean intensity of 5.0 recorded in C. tilapiae with P. obscura being the host fish species. The fish parasites and their hosts differ with respect to the standard length of the fish as shown in Table 5. In standard length that varied from 0 to 15 cm, Clinostomum sp. recorded the highest prevalence rate and mean intensity of 47.6% and 3.2, respectively, in C. kinsglayae while the least prevalence rate and mean intensity was observed in Lytocestus sp. A similar trend in Clinostomum sp. was observed in fish lengths that ranged between 20.1 and 25 cm with a high prevalence rate of 7.27% recorded in C. gariepinus and the least prevalence observed in E. heterostomum of the same fish species. P. leavionchus infected only O. niloticus of length between 25.1 and 30 cm with prevalence and mean intensity of 7.14% and 1.67, respectively. Also, P. leavionchus infested both H. odoe and P. obscura with high prevalence and intensity recorded in H. odoe and P. obscura, respectively.

Table 4

Checklist, location of infection, and overall prevalence and intensity of fish parasite in relation to fish species

Location of infectionParasite speciesHostNo. of Fish ExaminedNo. of Fish InfectedNo. of Parasite RecoveredPrevalence (%)Mean intensity
Gills Clinostomum tilapiae Ctenopoma kingsleyae 21 14.3 2.33 
Liver  Oreochromis niloticus 177 1.13 1.0 
Gill cover  Parachanna obscura 86 1.16 5.0 
Intestine Clinostomum sp. Ctenopoma kingsleyae 21 10 32 47.6 3.2 
Stomach  Marcusenius senegalensis 132 2.27 1.33 
Gills  Clarias gariepinus 110 18 7.27 2.25 
Body cavity Euclinostomum heterostomum Clarias gariepinus 110 0.91 1.0 
Stomach Procamallanus laevionchus Hepsetus odoe 14 14.3 1.0 
Intestine  Marcusenius senegalensis 132 14 21 10.6 1.5 
Gills  Oreochromis niloticus 177 2.82 1.8 
Gills  Parachanna obscura 86 12 3.49 4.0 
Eye Lytocestus sp. Ctenopoma kingsleyae 21 4.76 1.0 
Location of infectionParasite speciesHostNo. of Fish ExaminedNo. of Fish InfectedNo. of Parasite RecoveredPrevalence (%)Mean intensity
Gills Clinostomum tilapiae Ctenopoma kingsleyae 21 14.3 2.33 
Liver  Oreochromis niloticus 177 1.13 1.0 
Gill cover  Parachanna obscura 86 1.16 5.0 
Intestine Clinostomum sp. Ctenopoma kingsleyae 21 10 32 47.6 3.2 
Stomach  Marcusenius senegalensis 132 2.27 1.33 
Gills  Clarias gariepinus 110 18 7.27 2.25 
Body cavity Euclinostomum heterostomum Clarias gariepinus 110 0.91 1.0 
Stomach Procamallanus laevionchus Hepsetus odoe 14 14.3 1.0 
Intestine  Marcusenius senegalensis 132 14 21 10.6 1.5 
Gills  Oreochromis niloticus 177 2.82 1.8 
Gills  Parachanna obscura 86 12 3.49 4.0 
Eye Lytocestus sp. Ctenopoma kingsleyae 21 4.76 1.0 
Table 5

Prevalence and intensity of fish parasite in relation to fish lengths

Fish Standard Length (cm)Fish ParasiteFish Species (Host)NFENFINPRPrevalence (%)Mean Intensity
0–15.0 Clinostomum tilapiae C. kinsglayae 21 14.3 2.33 
 Clinostomum sp. C. kinsglayae 21 10 32 47.6 3.2 
 Lytocestus sp. C. kinsglayae 21 4.76 1.0 
 Procamallanus laevionchus M. senegalensis 52 14 21 26.9 1.5 
15.1–20.0 Clinostomum sp. M. senegalensis 80 3.75 1.33 
20.1–25.0 Clinostomum tilapiae O. niloticus 135 1.48 1.0 
 Clinostomum tilapiae P. obscura 56 1.79 5.0 
 Clinostomum sp. C. gariepinus 110 18 7.27 2.25 
 Procamallanus laevionchus P. obscura 56 1.79 3.0 
 Procamallanus laevionchus O. niloticus 135 1.48 2.0 
 Euclinostomum heterostomum C. gariepinus 110 0.91 1.0 
25.1–30.0 Procamallanus laevionchus O. niloticus 42 7.14 1.67 
30.1–35.0 Procamallanus laevionchus H. odoe 14 14.3 1.0 
 Procamallanus laevionchus P. obscura 30 6.67 4.5 
Fish Standard Length (cm)Fish ParasiteFish Species (Host)NFENFINPRPrevalence (%)Mean Intensity
0–15.0 Clinostomum tilapiae C. kinsglayae 21 14.3 2.33 
 Clinostomum sp. C. kinsglayae 21 10 32 47.6 3.2 
 Lytocestus sp. C. kinsglayae 21 4.76 1.0 
 Procamallanus laevionchus M. senegalensis 52 14 21 26.9 1.5 
15.1–20.0 Clinostomum sp. M. senegalensis 80 3.75 1.33 
20.1–25.0 Clinostomum tilapiae O. niloticus 135 1.48 1.0 
 Clinostomum tilapiae P. obscura 56 1.79 5.0 
 Clinostomum sp. C. gariepinus 110 18 7.27 2.25 
 Procamallanus laevionchus P. obscura 56 1.79 3.0 
 Procamallanus laevionchus O. niloticus 135 1.48 2.0 
 Euclinostomum heterostomum C. gariepinus 110 0.91 1.0 
25.1–30.0 Procamallanus laevionchus O. niloticus 42 7.14 1.67 
30.1–35.0 Procamallanus laevionchus H. odoe 14 14.3 1.0 
 Procamallanus laevionchus P. obscura 30 6.67 4.5 

The male fish species in the Esa-Odo reservoir had varying degrees of prevalence rate and mean intensity (Table 6). The maximum prevalence rate was recorded in Clinostomum sp. (42.1%) with C. kinsglayae recorded as the fish host when compared with E. heterostomum which had the least prevalence of 1.92%. Similarly, the mean intensity of 5.0 recorded in C. tilapiae was higher than the intensity of 1.0 in C. tilapiae and Lytocestus sp. which were recovered from C. kinsglayae. Also, in the female fish, the highest prevalence of 100% was recorded in Clinostomum sp. and P. leavionchus with C. kinsglayae and H. odoe as the fish host. High mean intensity of 4.0 was observed in Clinostomum sp. when compared to C. tilapiae, Clinostomum sp. and P. leavionchus which had the lowest value of 1.0 each.

Table 6

Prevalence and intensity of parasite infection from fish sample based on sex

Sex
Male
Female
Parasite speciesFish speciesNFENFINPRPrevalence (%)Mean IntensityNFENFINPRPrevalence (%)Mean Intensity
Clinostomum tilapiae C. kinsglayae 19 10.5 3.0 50 1.0 
 O. niloticus 91 2.2 1.0 86 
 P. obscura 46 2.17 5.0 40 
Clinostomum sp. C. gariepinus 52 12 9.62 2.4 58 5.17 2.0 
 C. kinsglayae 19 24 42.1 3.0 100 4.0 
 M. senegalensis 58 3.45 1.5 74 1.35 1.0 
Euclinostomum heterostomum C. gariepinus 52 1.92 1.0 58 
Procamallanus laevionchus H. odoe 12 100 1.0 
 M. senegalensis 58 12 17 20.7 1.42 74 2.7 2.0 
 O. niloticus 91 3.30 2.0 86 2.33 1.5 
 P. obscura 46 4.35 4.5 40 2.5 3.0 
Lytocestus sp. C. kinsglayae 19 5.26 1.0 
Sex
Male
Female
Parasite speciesFish speciesNFENFINPRPrevalence (%)Mean IntensityNFENFINPRPrevalence (%)Mean Intensity
Clinostomum tilapiae C. kinsglayae 19 10.5 3.0 50 1.0 
 O. niloticus 91 2.2 1.0 86 
 P. obscura 46 2.17 5.0 40 
Clinostomum sp. C. gariepinus 52 12 9.62 2.4 58 5.17 2.0 
 C. kinsglayae 19 24 42.1 3.0 100 4.0 
 M. senegalensis 58 3.45 1.5 74 1.35 1.0 
Euclinostomum heterostomum C. gariepinus 52 1.92 1.0 58 
Procamallanus laevionchus H. odoe 12 100 1.0 
 M. senegalensis 58 12 17 20.7 1.42 74 2.7 2.0 
 O. niloticus 91 3.30 2.0 86 2.33 1.5 
 P. obscura 46 4.35 4.5 40 2.5 3.0 
Lytocestus sp. C. kinsglayae 19 5.26 1.0 

Note: NFE, No. of fish examined; NFI, No. of fish infected; NPR, No. of parasites recovered.

In the correlation matrix table, all the parameters positively correlated with different fish parasites (Table 7). The water temperature had a strong positive correlation (p ≤ 0.01) with Clinostomum sp. abundance, a similar trend was observed in DO with a strong positive correlation with E. heterostomum. Also, there is a strong correlation between the DO of the reservoir water and the abundance of C. tilapiae and P. leavionchus recovered from the fish. E. heterostomum and Lytocestus sp. recorded a strong correlation with conductivity, alkalinity, phosphate, organic matter, COD, and turbidity. In the same vein, a significant correlation (p ≤ 0.05) was observed between P. leavionchus and some water quality parameters such as DO, conductivity, alkalinity, phosphate, and organic matter. The relationship between limnological variables and fish parasite abundance is presented in Figure 2. Parasites such as P. leaviochus, C. tilapiae, and Clinostomum sp. showed a closed relationship with DO and phosphate. Nitrate, water temperature, alkalinity clustered with E. heterostomum and Lytocestus sp.
Table 7

Correlation coefficient matrix showing relationship between the investigated limnological variables and fish parasites

Parasite speciesWater temp.DOpHECTDSAlkalinityNitratePhosphateOMCODTurbidity
Clinostomum tilapiae 0.317 0.804** 0.702** 0.201 0.435 0.714** 0.244 0.449 0.523* 0.142 0.142 
Clinostomum sp. 0.992*** 0.471 0.553* 0.552* 0.281 0.294 0.560* 0.308 0.443 0.812** 0.812** 
Euclinostomum heterostomum 0.484 0.952*** 0.208 0.762** 0.486 0.758** 0.289 0.860** 0.626* 0.762** 0.761** 
Procamallanus laevionchus 0.351 0.675* 0.211 0.643* 0.128 0.598* 0.469 0.673* 0.627* 0.139 0.138 
Lytocestus sp. 0.484 0.952** 0.208 0.762** 0.486 0.758** 0.289 0.860** 0.626* 0.762** 0.761** 
Parasite speciesWater temp.DOpHECTDSAlkalinityNitratePhosphateOMCODTurbidity
Clinostomum tilapiae 0.317 0.804** 0.702** 0.201 0.435 0.714** 0.244 0.449 0.523* 0.142 0.142 
Clinostomum sp. 0.992*** 0.471 0.553* 0.552* 0.281 0.294 0.560* 0.308 0.443 0.812** 0.812** 
Euclinostomum heterostomum 0.484 0.952*** 0.208 0.762** 0.486 0.758** 0.289 0.860** 0.626* 0.762** 0.761** 
Procamallanus laevionchus 0.351 0.675* 0.211 0.643* 0.128 0.598* 0.469 0.673* 0.627* 0.139 0.138 
Lytocestus sp. 0.484 0.952** 0.208 0.762** 0.486 0.758** 0.289 0.860** 0.626* 0.762** 0.761** 

*Significant (p < 0.05).

**Highly significant (p < 0.01).

***Very highly significant (p < 0.001).

Figure 2

Principal component analysis (PCA) showing the relationship between investigated limnological variables and fish parasites.

Figure 2

Principal component analysis (PCA) showing the relationship between investigated limnological variables and fish parasites.

Close modal

Limnological variables

Water quality parameters in an aquatic biota could be influenced by various human activities and other natural causes which may affect the aquatic environment. In this study, the value of the water temperature recorded was within the range documented for inland waterbodies in the tropical region (Adesakin et al. 2020; Anyanwu et al. 2021). This was also in agreement with Yusuf (2020) and Omoboye et al. (2022) who recorded a similar range for the water temperature in the tropics. The mean water temperature of 25.7 ± 0.72 °C observed in this study was within the recommended limit for fish (Egun & Oboh 2022). Some authors have suggested that the transfer of heat due to climatic change either from the air or sunlight might cause variations in the temperature of water (Arnell et al. 2015; Bello et al. 2017). Significant changes in both air and water temperatures during the dry season could be as a result of extreme harmattan and high intensity of sunlight in the habitat while moderate temperature in the rainy season might be due to heavy rainfall. The mean pH value ranged from 7.14 to 7.6 indicating that the reservoir water was slightly alkaline. However, the pH recorded for this study was in contrast with the findings of Koszelnik et al. (2018) who reported pH value that varied from 7.84 to 7.98 in Southeastern Poland reservoirs. Reasons for pH differences in reservoir water could be as a result of the temperature of the day, soil composition and bedrock.

The highest mean value (121 ± 6.82 μS/cm) of electrical conductivity was recorded in the transition zone while the lowest mean electrical conductivity (118 ± 7.44μS/cm) was recorded at the dam site. These findings were consistent with the results obtained by Adesakin et al. (2020) in Samaru River with a mean value of 128.67 ± 2.25 μS/cm. In Obudu river system of Opa reservoir, a mean temperature value of 122.59 ± 12.58 μS/cm was recorded (Aliu et al. 2020). The mean TDS (79.84 ± 6.52 mg/L) observed in this study was within the recommended limit for drinking water (WHO 2017) and for fish in the water (FAO 2006). A similar finding was also recorded by Ilechukwu et al. (2020) in Usuma Dam. However, Kalgwai dam (Edegbene 2020) recorded contrast values at three different sites that ranged from 108.5 to 141.8 mg/L.

TDS is the most significant to water quality when it concerns selected uses and has been listed by the Environmental Protection Agency as secondary ground water and drinking water pollutant (Akpan et al. 2007). Factors such as the type of water body, temperature as well as biological and chemical processes taking place in the reservoir determine the level of dissolved oxygen in the water (Manning 2017). The mean concentration of dissolved oxygen during the study period was 5.25 ± 1.61 mg/L. The levels recorded for DO in the reservoir were consistent with the work of Abowei et al. (2010) that a DO concentration of 5.0 mg/L and above is necessary for fish survival.

Alkalinity values (42.4 ± 7.14 mg/L CaCO3mg/L) observed in this study were characteristics of inland water bodies. The levels of Alkalinity were below the WHO permissible limit of 120 mg/L for drinking water. Some authors have suggested that anthropogenic activities are the main source of natural alkalinity (Onuoha & Alum-udensi 2018; Adeosun 2019). The results showed that the level of alkaline was within the permissible limits that support the growth and survival of fish in inland waterbodies (Komolafe et al. 2014; Ignatius & Rasmussen 2016).

The end product of the aerobic breakdown of organic nitrogenous substance are nitrates (Walakira & Okot-Okumu 2011). The concentration of nitrates in the Esa-Odo reservoir conforms to records from some investigated freshwater bodies in Nigeria such as the Erelu reservoir which recorded a mean nitrate value of 0.67 ± 0.06 mg/L (Kareem et al. 2018). Most of the water samples in each zone were within the permissible range of nitrate values as recommended by the Nigerian Standard for Drinking Water Quality (2007). In this current study, the mean phosphate value of 1.30 ± 0.61 mg/L was recorded. A possible explanation could be a result of NPK fertilizer being used by Nigerian farmers. Also, the catchment area of the reservoir is surrounded by farmlands. Moreover, the findings of the present study were in contrast with the report of Olanrewaju et al. (2017) which recorded phosphate levels between 1.9 and 2.0 mg/L in the Eleyele reservoir. Also, Oba reservoir, Ajala & Olatunde (2015) recorded phosphate levels of 0.09 and 0.07 during the rainy and dry seasons.

The mean values recorded for organic matter in the Esa-Odo reservoir ranged from 9.52 to 10.7 mg/L across the zones. In the Opa reservoir, Adesakin et al. (2017) documented organic matter levels with ranged between 0.63 and 14.54 mg/L at the surface level of the water. The level of organic matter in the Esa-Odo reservoir could probably be due to sediment properties and the soil-type of the reservoir. The nitrate level in any inland waterbodies indicated the level of nutrients and extent of organic matter pollution in the water body (Adesuyi et al. 2015). The mean chemical oxygen demand concentration recorded during the study period was 14.5 ± 4.47 mg/L. Irrespective of the period, the dam site had the lowest mean value of 13.56 ± 3.91mg/L. Similar values were reported in the Ogbese river by Akinbile & Omoniyi (2018) who recorded COD values that ranged between 5.70 and 49.00 mg/L in the reservoir. Turbidity of the reservoir had a mean value of 93.9 ± 29.87 NTU. The mean values of Turbidity in the rainy season (115 ± 4.13 NTU) was higher than the values recorded in the dry season (65.1 ± 3.57 NTU). Turbidity values recorded in the Esa-Odo reservoir were above the recommended limits of 5.0 NTU according to WHO and NSDWQ standard values. Increased turbidity could probably be a result of run-off from rainfall, and the movement of soil particles into the reservoir. An increase in turbidity has a significant impact on aquatic ecosystems since the effect is the reduction in light intensity for plants which is necessary for photosynthesis (Akinbile & Omoniyi 2018). Fish and other aquatic biotas that are resident in freshwater bodies might have physiologically evolved over some time to adapt to changes in water clarity associated with their habitat (Ajala & Fawole 2016).

Fish parasites recovered in the reservoir

The presence of parasites in fish during this study revealed the extent water quality can have on the composition and abundance of fish parasites which to some extent affects the health of the fish. Different parasites such as C. tilapiae, Clinostomum sp., E. heterostomum, P. leavionchus, and Lytocestus sp. recovered in this study are similar to reports carried out in other inland waterbodies on fish (Manning 2017; Osho 2019; Neves et al. 2020). According to Hussen et al. (2012), helminths parasites are mostly found in freshwater fish. The authors considered species of parasite and their biology, host and their diets, and the presence of intermediate hosts as contributing factors to the rate of infection and intensity. Natural and anthropogenic activities that find their way into the aquatic environment can influence the presence of free-living stages of fish parasites (Un Nissa et al. 2022). Parasites have been known to cause changes in growth, behavioral changes which are negative in reaction and mechanical injury (Iwanowicz 2011). In this study, prevalence rate was low (9.8%) when compared to other reports on fish parasites in the tropics reservoir (Okoye et al. 2014; Bedasso 2015; Oso et al. 2017). In order to survive, reproduce and have access to food, parasite depends on their host (Un et al. 2022). An intensity level of 2.15 was recorded in the fish parasites during this study was higher than the reports of Atalabi et al. (2018) who reported intensity that varied from 1.19 to 1.72 in Zobe dam.

In this study, the rate of prevalence at different fish lengths showed that as the length of fish increases the rate of infection also increases (Amos et al. 2018; Akinsanya et al. 2020). Changes in the rate of infection as a result of fish length could probably be due to diet changes and water column habitation of the fishes. In this present study, high prevalence of parasites occurred in the male fish than in the females and a significant prevalence rate in male fish has been previously reported (Adegoroye et al. 2019; Akinsanya et al. 2020). According to Reimchen & Nosil (2001), activities such as competition for mates, and territorial defence impose a demand on fish that may affect their immune system. This might be responsible for the overall high prevalence rate (12.97%) based on sex as recorded in male fishes. Abiyu et al. (2020) suggested that differences in the infection rate of male and female fish could be as a result of genetic makeup and differential vulnerability due to the differences in their physiological condition. Similarly, female fishes in the reservoir might have high resistance to parasites when compared with male fishes.

Relationship between limnological variables with respect to fish parasites load

The water quality of a waterbody in an aquatic biota regulates the primary productivity, composition of organisms, diversity, and abundance and serves as a bio-indicator of aquatic environment well-being (Koledoye et al. 2022). In this current study, some parasites strongly correlated with some limnological parameters such as dissolved oxygen, pH and conductivity showed a strong correlation with C. tilapiae. Water temperature, pH, conductivity, nitrate and chemical oxygen demand had a strong correlation with Clinostomum sp. and an increase in temperature tends to increase the rate of parasite infective stages (Khan 2012; Lõhmus & Björklund 2015; Ojwala & Otachi 2018). It has been established that water temperature has an effect on the abundance of monogenean parasites. Also, dissolved oxygen, conductivity, alkalinity, phosphate, and organic matter showed a positive correlation with P. leavionchus.

Productivity in water bodies could be a result of high levels of nutrients leading to healthy food chains for the population of intermediate hosts and an abundance of different parasitic stages (Bhatnagar & Devi 2013).

C. tilapiae, E. heterostomum, and Lytocestus sp. had life cycles which are transmitted from one host to another and are sensitive to changes in dissolved oxygen concentrations (Wangare et al. 2020). Dissolved oxygen, conductivity, alkalinity, phosphates, organic matter, and chemical oxygen demand showed a positive correlation with Lytocestus sp. Increased nutrient concentrations in waterbodies could lead to a decline in the water quality thereby making aquatic animals such as fish to be weak and exposed to parasites attack and infections (Sures 2004). Ecological variations have been recognized to affect parasitism, irrespective of whether the fish species are cultured or in the wild. This was due to exposure to environmental factors such as rainfall together with wind patterns that have the tendency to mix with the water column, thus increasing the likelihood of ingesting prey that are intermediate hosts (Pech et al. 2010).

Several studies show that there exist relationships between the environmental conditions and the level of parasites in the environment (Bayoumy et al. 2015; Kiprono 2017; Abba et al. 2018). The present condition of the reservoir showed that water quality properties had little effect on the parasitic loads of the fish which could be a result of the environment that has fewer anthropogenic activities.

The level of parasitism in this study could probably be as a result of the water quality parameters of the aquatic biota that favors low parasitic load. The overall water quality variables of the reservoir may be disturbed but it poses little threat to the survival and health of the fish. However, monitoring of the excess nutrient level in the reservoir is required for conservation purposes.

This study shows that there was a relationship between limnological variables and the abundance of fish parasites in the reservoir. The findings of this study suggested that fish parasites of freshwater are sensitive to changes in the quality of their biota and as bio-indicator of its quality. The freshwater parasites of this study were less abundant than the fish host which revealed less anthropogenic influence. Although parasites have to undergo some of their life cycles in intermediate or definite hosts, these hosts might be less numerically thereby affecting the parasitic community. Therefore, fish parasites can be used in monitoring and can serve as indications of the limnological quality of the biota.

O.O. performed the experiment, analyzed and interpreted the data, and wrote the paper. O.O.K. conceived and designed the experiments. E.E.O. analyzed the data and identified the parasites.

This study received no financial support or grant.

Data cannot be made publicly available; readers should contact the corresponding author for details.

The authors declare there is no conflict.

Abba
A. M.
,
Abdulkarim
B.
,
Omenesa
R. L.
,
Abdulhamid
Y.
&
M
I.
2018
Study on physico-chemical parameters and prevalence of fish parasites in Jibia
.
UMYU Journal of Microbiology Research
3
(
March
),
1
7
.
Abdullahi
M.
,
Iliyasu
D.
&
Ay
M.
2017
Journal of Veterinary Papers Contests of Intestinal Parasites and Haemoparasite in African Catfish (Clarias Gariepinus): Signal to Some Haematological Parameters for Optimum Production along Lake Chad Basin Area of Nigeria. 2(February), 1–5
.
Abiyu
M.
,
Mekonnen
G.
&
Hailay
K.
2020
Prevalence of internal nematode parasites of Nile tilapia (Oreochromis niloticus) fish species caught from southwestern part of Lake Tana, Central Gondar, Ethiopia
.
Journal of Aquaculture Research & Development
11
(
2
),
1
7
.
https://doi.org/10.35248/2155-9546.19.10.582
.
Abowei, J. F. N., Davies, O. A. & Eli, A. A. 2010 Physico-chemistry, morphology and abundance of finfish of Nkoro River, Niger Delta, Nigeria. International Journal of Pharma and Bio Sciences 1 (2), 1–11.
Adegoroye
F.
,
Omobhude
M.
&
Morenikeji
O.
2019
Helminth parasites of Synodontis clarias (Linnaeus, 1758), Chrysichthys nigrodigitatus (Lacepede 1802) and Chrysichthys auratus (Geoffrey Saint – Hilaire, 1808) in Asejire Dam, South – West Nigeria. 10(1), 37–47
.
Adeosun
F. I.
2019
Effects of anthropogenic activities on water quality, and phosphate and nitrates in the sediment of River Ogun at Ijaye, Isabo and Oke-sokori, Ogun State
.
International Journal of Biological and Chemical Sciences
13
(
3
),
1261
.
https://doi.org/10.4314/ijbcs.v13i3.4
.
Adesakin
T. A.
,
Adedeji
A. A.
,
Aduwo
A. I.
&
Taiwo
Y. F.
2017
Effect of discharges from re-channeled rivers and municipal runoff on water quality of Opa reservoir, Ile-Ife, Southwest Nigeria
.
African Journal of Environmental Science and Technology
11
(
1
),
56
70
.
https://doi.org/10.5897/ajest2016.2086
.
Adesakin
T. A.
,
Oyewale
A. T.
,
Bayero
U.
,
Mohammed
A. N.
,
Aduwo
I. A.
,
Ahmed
P. Z.
,
Abubakar
N. D.
&
Barje
I. B.
2020
Assessment of bacteriological quality and physico-chemical parameters of domestic water sources in Samaru community, Zaria, Northwest Nigeria
.
Heliyon
6
(
8
),
e04773
.
https://doi.org/10.1016/j.heliyon.2020.e04773
.
Adesuyi
A. A.
,
Nnodu
V. C.
,
Njoku
K. L.
&
Jolaoso
A. O.
2015
Nitrate and phosphate pollution in surface water of Nwaja Creek, Port Harcourt, Niger Delta, Nigeria Adeola
.
International Journal of Geology, Agriculture and Environmental Sciences
3
(
3
),
14
20
.
Ajala
O. O.
&
Fawole
O. O.
2016
Effects of Water Limnology and Enteroparasitic Infestation on Morphometrics of Oreochromis Niloticus (Linne, 1757) (Cichlidae) in a. August
.
Ajala
O. O.
&
Olatunde
F. O.
2015
Diets and enteroparasitic infestation of Oreochromis Niloticus (Linné, 1757) (Cichlidae) in Oba Reservoir Ogbomoso, Nigeria
.
Elixir Applied Zoology
83
(
June
),
32983
32988
.
Akinbile
C. O.
&
Omoniyi
O.
2018
Quality assessment and classification of Ogbese river using water quality index (WQI) tool
.
Sustainable Water Resources Management
4
(
4
),
1023
1030
.
https://doi.org/10.1007/s40899-018-0226-8
.
Akinsanya
B.
,
Ayanda
I. O.
,
Fadipe
A. O.
,
Onwuka
B.
&
Saliu
J. K.
2020
Heavy metals, parasitologic and oxidative stress biomarker investigations in Heterotis niloticus from Lekki Lagoon, Lagos, Nigeria
.
Toxicology Reports
7
,
1075
1082
.
https://doi.org/10.1016/j.toxrep.2020.08.010
.
Akpan
J. C.
,
Moses
F. A.
&
Ogugbuaja
V. O.
2007
Determination of pollutant levels in Mario Jose Tannery effluents from Kano Metropolis, Nigeria
.
Journal of Applied Sciences
7
(
4
),
527
530
.
Ali
M.
&
Faruk
R.
2018
Fish Parasite: Infectious Diseases Associated with Fish Parasite. CRC Press, Taylor & Francis Group, Philadelphia, PA, USA.
Aliu
O. O.
,
Akindele
E. O.
&
Adeniyi
I. F.
2020
Biological assessment of the headwater rivers of Opa Reservoir, Ile-Ife, Nigeria, using ecological methods
.
The Journal of Basic and Applied Zoology
81
(
1
).
https://doi.org/10.1186/s41936-020-00151-5
Amos
S. O.
,
Eyiseh
T. E.
&
Michael
E. T.
2018
Parasitic infection and prevalence in Clarias Gariepinus in Lake Gerio, Yola, Adamawa state
.
MOJ Anatomy & Physiology
5
(
6
),
376
381
.
https://doi.org/10.15406/mojap.2018.05.00229
.
Anyanwu
E. D.
,
Adetunji
O. G.
&
Umeham
S. N.
2021
Water quality and zooplankton community of the Eme River, Umuahia, Southeast Nigeria
.
Limnology and Freshwater Biology
5
,
1186
1194
.
https://doi.org/10.31951/2658-3518-2021-a-5-1186
.
APHA
1999
Standard Methods for the Examination of Water and Wastewater
.
American Public Health Association (APHA)
, Washington DC, Vol.
20
, p.
2671
.
Arnell
N. W.
,
Halliday
S. J.
,
Battarbee
R. W.
,
Skeffington
R. A.
&
Wade
A. J.
2015
The implications of climate change for the water environment in England
.
Progress in Physical Geography
39
(
1
),
93
120
.
https://doi.org/10.1177/0309133314560369
.
Atalabi
T. E.
,
Awharitoma
A. O.
&
Akinluyi
F. O.
2018
Prevalence, intensity, and exposed variables of infection with Acanthocephala parasites of the gastrointestinal tract of Coptodon zillii (Gervais, 1848) [ Perciformes : Cichlidae ] in Zobe Dam, Dutsin-Ma Local Government Area, Katsina State, Niger
.
Bayoumy
E. M.
,
Abou-El-Dobal
S. K. A.
&
Hassanain
M. A.
2015
Assessment of heavy metal pollution and fish parasites as biological indicators at Arabian gulf off Dammam Coast, Saudi Arabia
.
International Journal of Zoological Research
11
(
5
),
198
206
.
https://doi.org/10.3923/ijzr.2015.198.206
.
Bedasso
G. T.
2015
Study on the prevalence and temporal abundance of parasites of fishes in Lake Elan
. Global Journal of Fisheries and Aquaculture
3
(
7
),
265
269
.
Bello
A. A. D.
,
Hashim
N. B.
&
Haniffah
M. R. M.
2017
Predicting impact of climate change on water temperature and dissolved oxygen in tropical rivers
.
Climate
5
(
3
).
https://doi.org/10.3390/cli5030058
Bhatnagar
A.
&
Devi
P.
2013
Water quality guidelines for the management of pond fish culture
.
International Journal of Environmental Sciences
3
(
6
),
1980
2009
.
https://doi.org/10.6088/ijes.2013030600019
.
Biswas
J.
&
Pramanik
S.
2016
Assessment of aquatic environmental quality using gyrodactylus sp. as a living probe: parasitic biomonitoring of ecosystem health
.
Journal of Advances in Environmental Health Research
4
(
4
),
219
226
.
Budria
A.
&
Candolin
U.
2014
How does human-induced environmental change influence host-parasite interactions?
Parasitology
141
(
4
),
462
474
.
https://doi.org/10.1017/S0031182013001881
.
Buser
C. C.
,
Spaak
P.
&
Wolinska
J.
2012
Disease and pollution alter Daphnia taxonomic and clonal structure in experimental assemblages
.
Freshwater Biology
57
(
9
),
1865
1874
.
https://doi.org/10.1111/j.1365-2427.2012.02846.x
.
Bush, A. O., Lafferty, K. D., Lotz, J. M. & Shostak, A. W. Parasitology meets ecology on its own terms: Margolis et al. Revisited. The Journal of Parasitology 83 (4), 575–583. http://www.jstor.org/stable/3284227.
Carol
J.
,
Benejam
L.
,
Alcaraz
C.
,
Vila-Gispert
A.
,
Zamora
L.
,
Navarro
E.
,
Armengol
J.
&
García-Berthou
E.
2006
The effects of limnological features on fish assemblages of 14 Spanish reservoirs
.
Ecology of Freshwater Fish
15
(
1
),
66
77
.
https://doi.org/10.1111/j.1600-0633.2005.00123.x
.
Cauyan
G.
,
Briones
J. C.
,
De Leon
E.
,
Gonong
J.
,
Pasumbal
E. O.
,
Pelayo
M. C.
,
Piñera
M. A.
&
Papa
R. D.
2013
Initial assessment of parasite load in Clarias batrachus, Glossogobius giuris and Oreochromis niloticus in Lake Taal (Philippines)
.
Philippine Science Letters
6
(
1
),
21
28
.
Dougnon
J.
,
Montchowui
E.
,
Daga
F. D.
,
Houessiono
J.
,
Laleye
P.
&
Sakiti
N.
2012
Cutaneous and Gastrointestinal Helminth Parasites of the Fish Synodontis schall and Synodontis nigrita (Siluriformes: Mochokidae) from the lower Oueme Valley in South Benin
.
Research Journal of Biological Sciences
7
(
8
),
320
326
.
https://doi.org/10.3923/rjbsci.2012.320.326
.
Dzika
E.
&
Wyżlic
I.
2011
Fish parasites as quality indicators of aquatic environment
.
Zoologica Poloniae
54–55
(
1–4
),
59
65
.
https://doi.org/10.2478/v10049-010-0006-y
.
Egun
N. K.
&
Oboh
I. P.
2022
Freshwater source suitability for aquaculture : a case study of ikpoba freshwater source suitability for aquaculture : a case study of Ikpoba Reservoir, Edo State, Nigeria introduction globally, aquaculture has been acknowledged as a major contributor
.
Int. Sci. Technol. J. Namibia
15
(
February
),
50
56
.
Ejere
V. C.
,
Aguzie
O. I.
,
Ivoke
N.
,
Ekeh
F. N.
,
Ezenwaji
N. E.
,
Onoja
U. S.
&
Eyo
J. E.
2014
Parasitofauna of five freshwater fishes in a Nigerian freshwater ecosystem
.
Croatian Journal of Fisheries
72
(
1
),
17
24
.
https://doi.org/10.14798/72.1.682
.
Ekanem
A. P.
,
Eyo
V. O.
&
Sampson
A. F.
2011
Parasites of landed fish from Great Kwa River, Calabar, Cross River State, Nigeria
.
International Journal of Fisheries and Aquaculture
3
(
12
),
225
230
.
https://doi.org/10.5897/IJFA11.072
.
FAO
2006
The State of World Fisheries and Aquaculture
.
FAO
,
Rome
.
Galli
P.
,
Crosa
G.
,
Mariniello
L.
,
Ortis
M.
&
D'Amelio
S.
2001
Water quality as a determinant of the composition of fish parasite communities
.
Hydrobiologia
452
,
173
179
.
https://doi.org/10.1023/A:1011958422446
.
Hussen
A.
,
Tefera
M.
&
Asrate
S.
2012
Gastrointestinal helminth parasitesof clariasgariepinus (catfish) in lakehawassa, Ethiopia
.
Scientific Journal of Animal Science
1
(
4
),
131
136
.
Available from: www.Sjournals.com
Ibironke
O. C.
&
Morenikeji
O. A.
2018
Helminth parasites of Clarias gariepinus (Burchell, 1822) and Oreochromis niloticus (Linnaeus, 1758) from Esa Odo Reservoir, Esa Odo, South-West Nigeria
.
Researcher
10
(
March
),
44
52
.
https://doi.org/10.7537/marsrsj100818.06.Keywords
.
Ignatius
A. R.
&
Rasmussen
T. C.
2016
Small reservoir effects on headwater water quality in the rural-urban fringe, Georgia Piedmont, USA
.
Journal of Hydrology: Regional Studies
8
,
145
161
.
https://doi.org/10.1016/j.ejrh.2016.08.005
.
Ilechukwu
I.
,
Olusina
T. A.
&
Echeta
O. C.
2020
Physicochemical analysis of water and sediments of Usuma Dam, Abuja, Nigeria
.
Ovidius University Annals of Chemistry
31
(
2
),
80
87
.
https://doi.org/10.2478/auoc-2020-0015
.
Isichei
C. T.
,
Adeniyi
I. F.
,
Ogbuenunu
K. E.
&
Enordiana
I. O.
2020
Taxonomic composition and assessment of Phytoplankton Flora in Esa-Odo Reservoir, Osun State, Nigeria
.
Direct Research Journal of Biology and Biotechnology
6
(
August
),
64
74
.
Iwanowicz
D. D.
2011
Overview on the effects of parasites on fish health
. In:
Proceedings of the Third Bilateral Conference Between Russia and the United States. Bridging America and Russia with Shared Perspectives on Aquatic Animal Health
,
June
, pp.
176
184
.
Kareem
O. K.
,
Ajani
E. K.
,
Omitoyin
B. O.
,
Olanrewaju
A. N.
,
Orisasona
O.
&
Osho
E. F.
2018
Spatial and temporal limnological status of Erelu Reservoir, southwestern Nigeria
.
Ife Journal of Science
20
(
3
),
509
.
https://doi.org/10.4314/ijs.v20i3.5
.
Khalil
M. I.
,
El-Shahawy
I. S.
&
Abdelkader
H. S.
2014
Estudos sobre alguns parasitas de peixes com importância para a saúde pública na região sul da Arábia Saudita
.
Revista Brasileira de Parasitologia Veterinaria
23
(
4
),
435
442
.
https://doi.org/10.1590/S1984-29612014082
.
Khan
R. A.
2012
Host-parasite interactions in some fish species
.
Journal of Parasitology Research
2012
.
https://doi.org/10.1155/2012/237280
Kiprono
S.
2017
Fish Parasites and Fisheries Productivity in Relation To
.
Koledoye
T. Y.
,
Akinsanya
B.
,
Adekoya
K. O.
&
Isibor
P. O.
2022
Physicochemical parameters of the Lekki Lagoon in relation to abundance of Wenyonia sp Woodland, 1923 (Cestoda : Caryophyllidae) in Synodontis clarias (Linnaeus, 1758)
.
Environmental Challenges
7
(
January
),
100453
.
https://doi.org/10.1016/j.envc.2022.100453
.
Komolafe
O.
,
Adedeji
A.
&
Fadairo
B.
2014
Assessment of the water quality parameters in relation to fish community of Osinmo reservoir, Ejigbo, Osun State, Nigeria
.
International Journal of Biological and Chemical Sciences
8
(
2
),
596
.
https://doi.org/10.4314/ijbcs.v8i2.18
.
Koszelnik
P.
,
Kaleta
J.
&
Bartoszek
L.
2018
An assessment of water quality in dam reservoirs, considering their aggressive properties
. In:
E3S Web of Conferences
, Vol.
45
.
https://doi.org/10.1051/e3sconf/20184500035
Kutz
S. J.
,
Hoberg
E. P.
,
Polley
L.
&
Jenkins
E. J.
2005
Global warming is changing the dynamics of Arctic host-parasite systems
.
Proceedings of the Royal Society B: Biological Sciences
272
(
1581
),
2571
2576
.
https://doi.org/10.1098/rspb.2005.3285
.
Kutzer
M. A. M.
&
Armitage
S. A. O.
2016
Maximising fitness in the face of parasites: a review of host tolerance
.
Zoology
119
(
4
),
281
289
.
https://doi.org/10.1016/j.zool.2016.05.011
.
Larsen
M. H.
&
Mouritsen
K. N.
2014
Temperature-parasitism synergy alters intertidal soft-bottom community structure
.
Journal of Experimental Marine Biology and Ecology
460
,
109
119
.
https://doi.org/10.1016/j.jembe.2014.06.011
.
Lazzaro
B. P.
&
Little
T. J.
2009
Immunity in a variable world
.
Philosophical Transactions of the Royal Society B: Biological Sciences
364
(
1513
),
15
26
.
https://doi.org/10.1098/rstb.2008.0141
.
Lõhmus
M.
&
Björklund
M.
2015
Climate change: what will it do to fish-parasite interactions?
Biological Journal of the Linnean Society
116
(
2
),
397
411
.
https://doi.org/10.1111/bij.12584
.
Manning
C. C.
2017
Insight into chemical, biological, and physical processes in coastal waters from dissolved oxygen and inert gas tracers
.
Insight Into Chemical, Biological, and Physical Processes in Coastal Waters From Dissolved Oxygen and Inert Gas Tracers
213
.
https://doi.org/10.1575/1912/8589
Margolis
L.
,
Esch
G. W.
&
Holmes
J. C.
1982
The use of ecological terms in parasitology (report of an ad hoc committee of the American society of parasitologists)
.
Journal of Parasitology
68
(
1
),
131
133
.
https://doi.org/10.2307/3281335
.
Neves
L. R.
,
Silva
L. M. A.
,
Florentino
A. C.
&
Tavares-Dias
M.
2020
Distribution patterns of procamallanus (Spirocamallanus) inopinatus (nematoda: Camallanidae) and its interactions with freshwater fish in Brazil
.
Revista Brasileira de Parasitologia Veterinaria
29
(
4
),
1
15
.
https://doi.org/10.1590/S1984-29612020092
.
Nigerian Standard for Drinking Water Quality
2007
Nigerian Standard for Drinking Water Quality. 52, 19–24
.
Ojwala
R. A.
&
Otachi
E. O.
2018
Effect of water quality on the parasite assemblages infecting Nile tilapia in selected fish farms in Nakuru County, Kenya. Allison 2011
.
Okoye
I. C.
,
Abu
S. J.
,
Obiezue
N. N. R.
&
Ofoezie
I. E.
2014
Prevalence and seasonality of parasites of fish in Agulu Lake, Southeast, Nigeria
.
African Journal of Biotechnology
13
(
3
),
502
508
.
https://doi.org/10.5897/ajb2013.13384
.
Olanrewaju
A.
,
Ajani
E.
&
Kareem
O.
2017
Physico-chemical status of Eleyele Reservoir, Ibadan, Nigeria
.
Journal of Aquaculture Research & Development
08
(
09
).
https://doi.org/10.4172/2155-9546.1000512
Olurin
K. B.
&
Somorin
C. a.
2006
Intestinal Helminths of the fishes of Owa Stream, South-west Nigeria
.
Biological Research
1
(
1
),
6
9
.
Omeji
S.
,
Solomon
S. G.
&
Idoga
E. S.
2011
A comparative study of the common protozoan parasites of Clarias gariepinus from the wild and cultured environments in Benue State, Nigeria
.
Journal of Parasitology Research
2011
.
https://doi.org/10.1155/2011/916489
Omoboye
H. Y.
,
Aduwo
A. I.
,
Adewole
H.
&
Adeniyi
I. F.
2022
Water quality and planktonic community of Owalla Reservoir, Osun State, Southwest Nigeria
.
Acta Limnologica Brasiliensia
34
.
https://doi.org/10.1590/s2179-975 × 1820
Oniye
S.
,
Adebote
D.
&
Ayanda
O.
2004
Helminth parasites of Clarias gariepinus (Teugels) in Zaria, Nigeria
.
Journal of Aquatic Sciences
19
(
2
).
https://doi.org/10.4314/jas.v19i2.20027
Onuoha
P.
&
Alum-udensi
O.
2018
Impacts of anthropogenic activities on water quality of the Onuimo Section of Imo River, Imo State, Nigeria
.
International Journal of Agriculture and Earth Science
4
(
4
),
44
52
.
Onyedineke
N. E.
,
Obi
U.
,
Ofoegbu
P. U.
&
Ukogo
I.
2010
Helminth parasites of some freshwater fish from River Niger at Illushi, Edo State, Nigeria
.
Journal of American Science
6
(
3
),
16
21
.
Osho
F.
2019
Parasitic Helminth Fauna of Parachanna obscura in River Ogun, Parasitic Helminth Fauna of Parachanna obscura in River Ogun, Southwest Nigeria. January 2017
.
Oso
J.
,
Idowu
E.
,
Adewumi
A.
&
Longe
D.
2017
Prevalence of parasites infection of resident fish species in a tropical reservoir
.
Asian Journal of Biology
2
(
3
),
1
7
.
https://doi.org/10.9734/ajob/2017/33229
.
Palm
H. W.
2011
Progress in Parasitology
.
https://doi.org/10.1007/978-3-642-21396-0
Paperna
I.
1996
Parasites, infections and diseases of fishes in Africa (Vol. 23). An update CIFA Technical Paper. No.31. Rome, FAO. 1996. 220p
.
Paugy, D., Leveque, C. & Teugels, G. G. 2003 The Fresh and Brackish Water Fishes of West Africa. Scientific Publications of the Museum Diffusion, Belgium, p. 843.
Pech
D.
,
Aguirre-Macedo
M. L.
,
Lewis
J. W.
&
Vidal-Martínez
V. M.
2010
Rainfall induces time-lagged changes in the proportion of tropical aquatic hosts infected with metazoan parasites
.
International Journal for Parasitology
40
(
8
),
937
944
.
https://doi.org/10.1016/j.ijpara.2010.01.009
.
Reimchen
T. E.
&
Nosil
P.
2001
Ecological causes of sex-biased parasitism in threespine stickleback
.
Biological Journal of the Linnean Society
73
(
1
),
51
63
.
https://doi.org/10.1006/bijl.2001.0523
.
Scharsack
J. P.
,
Schweyen
H.
,
Schmidt
A. M.
,
Dittmar
J.
,
Reusch
T. B. H.
&
Kurtz
J.
2012
Population genetic dynamics of three-spined sticklebacks (gasterosteus aculeatus) in anthropogenic altered habitats
.
Ecology and Evolution
2
(
6
),
1122
1143
.
https://doi.org/10.1002/ece3.232
.
Sures
B.
2004
Environmental parasitology: relevancy of parasites in monitoring environmental pollution
.
Trends in Parasitology
20
(
4
),
170
177
.
https://doi.org/10.1016/j.pt.2004.01.014
.
Un
N.
,
Jan
M.
,
Ahmad
J.
,
Ahmad
N.
,
Jan
A.
,
Ahmad
F.
,
Ahamad
B.
&
Gulnaz
A.
2022
Saudi Journal of Biological Sciences Parasitic anomalies observed in snow trout due to anthropogenic stress in water bodies
.
Saudi Journal of Biological Sciences
29
(
4
),
2921
2925
.
https://doi.org/10.1016/j.sjbs.2022.01.022
.
Unger
P.
,
Klimpel
S.
,
Lang
T.
&
Palm
H. W.
2014
Metazoan parasites from herring (Clupea harengus L.) as biological indicators in the Baltic Sea
.
Acta Parasitologica
59
(
3
),
518
528
.
https://doi.org/10.2478/s11686-014-0276-5
.
Un Nissa
N.
,
Jan
M.
,
Tantray
J. A.
,
Dar
N. A.
,
Jan
A.
,
Ahmad
F.
,
Paray
B. A.
&
Gulnaz
A.
2022
Parasitic anomalies observed in snow trout due to anthropogenic stress in water bodies
.
Saudi Journal of Biological Sciences
29
(
4
),
2921
2925
.
https://doi.org/10.1016/j.sjbs.2022.01.022
.
Uruku
M. N.
&
Adikwu
I. A.
2017
Seasonal prevalence of parasites of clariids fishes from the Lower Benue River
.
Nigerian Journal of Fisheries and Aquaculture
5
(
September
),
11
19
.
Walakira
P.
&
Okot-Okumu
J.
2011
Impact of industrial effluents on water quality of streams in Nakawa-Ntinda, Uganda
.
Journal of Applied Sciences and Environmental Management
15
(
2
).
https://doi.org/10.4314/jasem.v15i2.68512
Wangare
S.
,
Adamba
K.
,
Onyango
E.
,
Geoffrey
O.
&
Ong
O.
2020
Parasite communities of Oreochromis niloticus baringoensis (Trewavas, 1983) in relation to selected water quality parameters in the springs of Lorwai Swamp and Lake Baringo, Kenya
.
Acta Parasitologica
.
0123456789. https://doi.org/10.2478/s11686-020-00178-2
Waruiru
R. M.
,
Mbuthia
P. G.
,
Wanja
D. W.
&
Mwadime
J. M.
2021
Prevalence, intensity and influence of water quality on parasites offarmed fish in Kirinyaga County, Kenya
.
Livestock Research for Rural Development
32
,
10
.
WHO
2017
Guidelines for Drinking-water Quality. In FOURTH EDITION INCORPORATING THE FIRST ADDENDUM. https://doi.org/10.5005/jp/books/11431_8
Yamaguti
S.
1958
© 1959 Nature Publishing Group. Systema Helminthum. Vol. 1. The Trematodes of Vertebrates. Inter-science publishers, Inc. New York. Nature Publishing Group
.
Yerima
R.
,
Bolorunduro
P.
,
Suleiman
B.
&
Usman
L.
2017
Temporal variation of fish species composition, abundance and diversity in relation to physicochemical characteristics of Dadin Kowa Reservoir Gombe State-Nigeria
.
International Journal of Applied Research
8
(
2
),
149
165
.
Yusuf
Z. H.
2020
Phytoplankton as bioindicators of water quality in nasarawa reservoir, Katsina State Nigeria
.
Acta Limnologica Brasiliensia
32
.
https://doi.org/10.1590/s2179-975 × 3319
This is an Open Access article distributed under the terms of the Creative Commons Attribution Licence (CC BY 4.0), which permits copying, adaptation and redistribution, provided the original work is properly cited (http://creativecommons.org/licenses/by/4.0/).