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This research was designed to study the parasitic infection and prevalence of juvenile and adult stages of Clarias gariepinus in Lake Geriyo. The study was conducted between June and November, 2016. A total of one hundred and thirty-two (132) fish were sampled for parasitic investigation. Out of these, adults (66) and juveniles (66), were procured from fishermen at the landing site. They were examined for parasitic infections using direct wet mount microscopy and stained smears. Fish body weights, and total length, were determined. Data generated were analysed using t-test and chisquare. The results showed that, a total number of 60 adult C. gariepinus were infected out of which 316 parasites were recovered, while in juvenile C. gariepinus, a total of 41 fish were infected in which 80 parasites were recovered. Parasitic infestations in the adult and juvenile females were significantly higher than male adults and juvenile with 91.11% for female adult and 66.67% for female juvenile. Nine classes of parasites and nineteen (19) parasites species were recorded from the gills, stomach, intestine, and skin mucus in the research study. There were significant differences (p<0.05) between incidence of infestation and standard length and body weight of Clarias gariepinus.

This study was conducted to evaluate the effect of fish processors on the nutritional quality of some commercial fish species (Clarias gariepinus, Synodontis budgetti, and Oreochromis niloticus) which obtained from Lake Geriyo, Yola, Nigeria. One kilogram of each of the fish species was processed using Futy Smoking Kiln (FSK), Improved Hanger Smoking Kiln (IMHSK) and Hybrid Solar Drier (HSD). Each of the three fish species were randomly assigned to the three (3) processors in a completely randomized design replicated thrice containing one (1) kilogram of each of the fish species and processed. The time and weights were recorded. Processed Fish samples were analyzed for proximate and mineral composition, using standard laboratory procedure. Data were also collected on organoleptic taste, and cost benefit using the different processors. Data obtained were subjected to the analysis of variance. Decrease in moisture content was observed during processing using the different processors and constant weight was obtained within 10-20 hours. The proximate composition of the differently processed fish species were significantly (p<0.05) affected by the different processors. The IMHSK recorded the highest crude protein of (65.42%) for Synodontis budgetti and 62.76% for Oreochromis niloticus respectively, The IMHSK indicated significantly (p<0.05) higher calcium level of 3.53 mg/kg for Clarias gariepinus and 4.77 mg/kg for Synodontis budgetti. The different processors used significantly (p<0.05) affected the level of acceptability of the processed fish. Fish processed using the improved hanger smoking kiln recorded the highest level of acceptability followed by those processed with Futy smoking kiln. On economic ground, the use of IMHSK was found to be cost effective. The different processors used were observed to influence the nutritional quality of fish however; the use of IMHSK indicated the most beneficial effects on the nutritive value of fish and is therefore recommended for processing fish.

The paper attempts to examine the current trends of artisanal fisheries practices in inland waters of Nigeria. The paper discussed the potentials of inland fisheries resources, its advantages and the pressure on inland fisheries resources of Nigeria. Despites efforts by relevant agencies, bodies and institutions through regulations, control and monitoring, Unsustainable fisheries practices such as overfishing, use of destructive and damaging fishing methods as well as illegal, unregulated and unreported fisheries practices are still common practices among artisanal fishers in Nigeria. There is low adherence and compliance to fisheries regulations and sustainable fisheries practices among the artisanal fishers. These unsustainable fisheries practices are threatening the sustainability and benefits of the inland fisheries resources.The paper also highlights the current challenges facing and militating against the sustainable development of artisanal fisheries in Nigeria, fisheries sustainability objectives and ecosystem effects of fishing. There is need for swift adoption and implementation of measures that will ensure sustainable exploitation, development and management of the inland fisheries resources of Nigeria. The paper recommends the need for enlightenment campaign on sustainable fisheries practices, regular programmers of overfished and depleted water bodies and integrates artisanal fishers as key stakeholders in fisheries policy formulation, management. Diversifying or providing an alternative source of income for the artisanal fishers would reduce the pressure on the resources by engaging in non-fishing activities. The need to strictly implement the newly enacted Inland fisheries Act, 2014 cannot be overemphasized.

This study determined the levels of benzo(a)pyrene in smoked Clarias gariepinus and Heterotis niloticus.Questionnaire was administered to fish processors at the Hadejia and Geriyo fish processing units, the result obtained from analysis of the questionnaire shows that majority of the fish processors in Hadejia are using Neem tree (Azadrachta indica) wood and rectangular smoking kiln while in Geriyo majority of the fish processors are using Chew stick tree (Anageisus leiocarpus) wood and Drum smoking kiln. Sample of fish processed were collected and also fresh fish were processed using the type of firewood commonly used by the fish processors. The Fresh fish samples were used as control. All the smoked and fresh fish samples were subjected to laboratory analysis to determine the level of benzo(a)pyrene. Data generated were subjected to One-way ANOVA. The results obtained show that highest Benzo(a)pyrene recorded in this study is from C. gariepinus smoked in Hadejia market having 14.91 µg/kg followed by the same species smoked in Geriyo with 13.69 µg/kg of BaP while the lowest was recorded in H. niloticus smoked with chew stick with 7.61µg/kg. There is significant difference (p<0.05) in the level of BaP in smoked Clarias gariepinusand Heterotis niloticus across the samples. All the smoked fish samples examined in this study were found to be higher than the acceptable limit (5 µg/kg) specified by the European Union commission, but when they were evaluated according to FAO/WHO limits (10 µg/kg). Four samples (40%) analyzed were over

The study was conducted in Gesedaddo's farm, Yola, Adamawa state, Nigeria to determine the prevalence of parasites infecting Clarias gariepinus between June to November, 2016. A total of one hundred and thirty-two (132) fish were sampled for parasitic investigation. Out of these, cultured adults (66) and cultured juveniles (66) respectively were procured from the farm and examined for parasites using the keys of fresh water fish parasite pictorial guide and were examined for parasitic infections using direct wet mount microscopy and stained smears. A total number of 43 adult Clarias gariepinus were infected out of which 132 parasites were identified, while in juvenile Clarias gariepinus, a total number of 10 fish were infected in which 30 parasites were identified in Gesedaddo's farm. Seven (7) classes of parasites and eleven (11) parasite species, which are namely, Piscinoodinium, (Dinoflagellata), Coccidia, Spironucleus vortens, (Flagellata), Chilodonella, Tetrehymena, (Motile ciliate), Capillaria, Contracaecum, (Nematoda), Microsporidians, (Protozoa), Saprolegnia sp, (Oomycota), Digeneans, and Planarian (Trematoda) were recorded from the gills, stomach, intestine, and skin mucus of the cultured Clarias gariepinus on the farm. Parasitic infestation was higher in the intestine with 63 (47.73) and the least was identified 6 (4.55) on the skin for adult Clarias gariepinus while the highest number of parasites identified in juvenile Clarias gariepinus was found on the skin with total number of 11 (36.67). Among the class of parasites identified, it was recorded that the highest parasitic load occurred most in the class protozoan with 45 (34.09%) and 17 (56.67) in adult and Juvenile C. gariepinus respectively. The Chi square value shows that there was no significant difference (p>0.05) between the prevalence and intensity of parasitic infection in adults and juvenile C. gariepinus based on sex. Parasitic infestations in the adult and juvenile female were significantly higher than in the adult and juvenile male in cultured Clarias gariepinus. There was a significant difference between incidence of infestation, standard length and body weight of Clarias gariepinus while there was no significant difference (p> 0.05) between parasitic load.